Bispecific antibodies that bind to coagulation factor IX and coagulation factor X

JP7637166B2Active Publication Date: 2025-02-27BIOVERATIV THERAPEUTICS INC
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Patent Information

Application Number
JP2023017261
Authority / Receiving Office
JP · JP
Patent Type
Patents
Current Assignee / Owner
Priority Date
2017-11-16
Filing Date
2023-02-08
Publication Date
2025-02-27
Estimated Expiration
2037-11-22

AI Technical Summary

Benefits of technology

【0008】 本開示は、活性化第IX因子(FIXa)に特異的に結合する単離された抗体またはその抗原結合部分(「抗FIXa抗体またはその抗原結合部分」)であって、抗FIXa抗体またはその抗原結合部分が、FIXaおよび第IX因子チモーゲン(FIXz)の存在下でFIXaに優先的に結合する、抗FIXa抗体またはその抗原結合部分を提供する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、抗FIXa抗体またはその抗原結合部分のFIXzに対する結合親和性よりも高い結合親和性でFIXaに結合する。本開示はまた、抗FIXa抗体またはその抗原結合部分のFIXzに対する結合親和性よりも高い結合親和性でFIXaに結合する、単離された抗FIXa抗体またはその抗原結合部分を提供する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、バイオレイヤー干渉法(BLI)アッセイによって決定すると、約100nM以下、約90nM以下、約80nM以下、約70nM以下、約60nM以下、約50nM以下、約40nM以下、約30nM以下、約20nM以下、約10nM以下、約8nM以下、約6nM以下、約4nM以下、約2nM以下、約1nM以下のKDで、FIXaに結合する。一部の態様では、FIXaは、遊離FIXa、テナーゼ複合体中のFIXa、またはEGR-CMKに共有結合により連結されているFIXa(FIXa-SM)である。一部の態様では、FIXzは、活性化不能型第IX因子(FIXn)を含む。一部の態様では、抗FIXa抗体またはその抗原結合部分は、図3A、図3Bおよび図3C中の抗体からなる群から選択される参照抗体と交差競合する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、図3A、図3Bおよび図3C中の抗体からなる群から選択される参照抗体と同じエピトープに結合する。一部の態様では、このような参照抗体は、BIIB-9-484、BIIB-9-440、BIIB-9-882、BIIB-9-460、BIIB-9-433およびそれらの任意の組合せから選択される。一部の態様では、抗FIXa抗体またはその抗原結合部分は、遊離FIXaもしくはFIXzと比べて、FIXa-SMに優先的に結合するか、および/または遊離FIXaもしくはFIXzに対する抗FIXa抗体またはその抗原結合部分の結合親和性よりも高い結合親和性で、FIXa-SMに結合する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、図3A中の抗体からなる群から選択される参照抗体と交差競合する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、図3A中の抗体からなる群から選択される参照抗体と同じエピトープに結合する。一部の態様では、このような参照抗体は、BIIB-9-484、BIIB-9-440、BIIB-9-460およびそれらの任意の組合せから選択される。一部の態様では、抗FIXa抗体またはその抗原結合部分は、FIXa-SMもしく はFIXzと比べて、遊離FIXaに優先的に結合するか、および/またはFIXa-SMもしくはFIXzに対する抗FIXa抗体またはその抗原結合部分の結合親和性よりも高い結合親和性で、遊離FIXaに結合する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、図3B中の抗体からなる群から選択される参照抗体と交差競合する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、図3B中の抗体からなる群から選択される参照抗体と同じエピトープに結合する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、FXzと比べて遊離FIXaもしくはFIXa-SMに優先的に結合するか、および/または抗FIXa抗体またはその抗原結合部分のFIXzに対する結合親和性よりも高い結合親和性で、遊離FIXaまたはFIXa-SMに結合する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、図3C中の抗体からなる群から選択される参照抗体と交差競合する。一部の態様では、抗FIXa抗体またはその抗原結合部分は、図3C中の抗体からなる群から選択される参照抗体と同じエピトープに結合する。一部の態様では、このような参照抗体は、BIIB-9-882、BIIB-9-433およびそれらの組合せから選択される。一部の態様では、抗FIXa抗体またはその抗原結合部分は、CDR1、CDR2およびCDR3を含み、CDR3は、図3A、図3Bおよび図3C中のVH CDR3または1つもしくは2つの変異を有するVH CDR3からなる群から選択されるVH CDR3を含む。一部の態様では、抗FIXa抗体またはその抗原結合部分は、CDR1、CDR2およびCDR3を含み、CDR3は、ARDX1X2X3X4X5X6YYX7MDV(配列番号753)を含み、X1はVまたはGであり、X2は、GまたはVであり、X3は、GまたはRであり、X4は、YまたはVであり、X5は、AまたはSであり、X6は、GまたはDであり、X7は、Gであるか、または存在しない。一部の態様では、CDR3は、ARDVGGYAGYYGMDV(配列番号905、BIIB-9-484、1335、1336)、ARDISTDGESSLYYYMDV(配列番号901、BIIB-9-460)、ARGPTDSSGYLDMDV(配列番号1186、BIIB-9-882)またはARDGPRVSDYY MDV(配列番号912、BIIB-9-619)を含む。一部の態様では、抗FIXa抗体またはその抗原結合部分は、CDR1、CDR2およびCDR3を含み、CDR1は、図3A、図3Bおよび図3C中のVH CDR1または1つもしくは2つの変異を有するVH CDR1からなる群から選択されるVH CDR1を含む。一部の態様では、抗FIXa抗体またはその抗原結合部分は、VH CDR1、CDR2およびCDR3を含み、CDR2は、図3A、図3Bおよび図3C中のVH CDR2または1つもしくは2つの変異を有するVH CDR2からなる群から選択されるVH CDR2を含む。一部の態様では、抗FIXa抗体またはその抗原結合部分は、VL CDR1、CDR2およびCDR3を含み、CDR1は、図3A、図3Bおよび図3C中のVL CDR1または1つもしくは2つの変異を有するVL CDR1からなる群から選択されるVL CDR1を含む。一部の態様では、抗FIXa抗体またはその抗原結合部分は、VL CDR1、CDR2およびCDR3を含み、CDR2は、図3A、図3Bおよび図3C中のVL CDR2または1つもしくは2つの変異を有するVL CDR2からなる群から選択されるVL CDR2を含む。一部の態様では、抗FIXa抗体またはその抗原結合部分は、VL CDR1、CDR2およびCDR3を含み、CDR3は、図3A、図3Bおよび図3C中のVL CDR3または1つもしくは2つの変異を有するVL CDR3からなる群から選択されるVL CDR3を含む。

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Abstract

Antibodies or antigen-binding portions thereof that bind to activated coagulation factor IX are provided. [Solution] An isolated antibody or antigen-binding portion thereof that specifically binds to activated coagulation factor IX (FIXa), wherein the anti-FIXa antibody or antigen-binding portion thereof preferentially binds to FIXa in the presence of FIXa and factor IX zymogen (FIXz), or the anti-FIXa antibody or antigen-binding portion thereof binds to FIXa with a binding affinity higher than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof for FIXz.
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Description

[Technical Field]

[0001] Reference to previous application This application claims the benefit of U.S. Provisional Patent Application No. 62 / 425,921, filed November 23, 2016, U.S. Provisional Patent Application No. 62 / 452,809, filed January 31, 2017, U.S. Provisional Patent Application No. 62 / 529,805, filed July 7, 2017, and U.S. Provisional Patent Application No. 62 / 587,284, filed November 16, 2017, which are incorporated by reference in their entireties.

[0002] Referencing electronically filed sequence listings via EFS-WEB The contents of the electronically submitted Sequence Listing filed with this application (Name: 4159.485PC04_Sequence_listing_ST25.txt; Size: 1,053,370 bytes; and Created on November 21, 2017) are hereby incorporated by reference in their entirety.

[0003] The present application relates, inter alia, to antibodies that preferentially bind to activated coagulation factor IX or coagulation factor X zymogen, as well as bispecific molecules that contain both specificities that mimic activated factor VIII cofactor. [Background technology]

[0004] Hemophilia A is a severe X-linked recessive disorder caused by mutations in the factor VIII (FVIII) gene. FVIII is involved in the latent pathway of blood clotting, and a deficiency of FVIII results in poor or complete clotting of blood. FVIII deficiency, alternatively known as hemophilia A, is one of the most common bleeding disorders, affecting approximately 1 in 10,000 males (Non-Patent Document 1). Hemophilia A has three grades of severity, defined by plasma levels of factor FVIII below 1% ("severe"), 2-5% ("moderate"), and 6-30% ("mild") (Non-Patent Document 2). In severe forms of the disorder, first bleeding usually occurs at 5-6 months of age, while in moderate forms, this first bleeding is delayed until approximately 1-2 years of age. Bleeding can occur spontaneously or after minimal trauma. Approximately half of all patients with hemophilia A are classified as having a severe form of the disease. These patients experience severe bleeding beginning in early childhood and frequent episodes of spontaneous or excessive bleeding later in life. Bleeding commonly occurs in joints and muscles, and without appropriate treatment, recurrent bleeding can lead to irreversible hemoarthropathy (Non-Patent Document 3).

[0005] An important goal of treating hemophilia A is to maintain plasma FVIII levels at ≥1%, thereby reducing the risk of bleeding. To achieve this, recombinant or plasma-derived FVIII is frequently administered intravenously as a prophylactic treatment. However, the current standard treatment for hemophilia A is challenging, has several drawbacks, and imposes a considerable physical and psychological burden on patients and their families. [Prior art documents] [Non-patent literature]

[0006] [Non-Patent Document 1] Stonebraker et al. (2012) Haemophilia 18(3):e91-4 [Non-patent document 2] White et al. (2001) Thromb. Haemost. 85:560 [Non-patent document 3] Manco-Johnson et al. (2007) N. Engl. J. Med. 357(6):535-44 Summary of the Invention [Problem to be solved by the invention]

[0007] The most common adverse effect of FVIII treatment is the development of alloantibodies against FVIII, which act as FVIII inhibitors. As many as 30% of severely affected patients develop these alloantibodies, which, once established, limit the effectiveness of FVIII for treating ongoing bleeding (Kempton and White (2009) Blood 113(1):11-7). In such cases, alternative drug-free approaches are used to control bleeding. However, these drugs typically have shorter half-lives and are not always effective. Furthermore, the short plasma half-life (average approximately 12 hours in adults and even shorter in children) necessitates frequent administration of FVIII. This regimen can be difficult, especially in young children. Because available treatments are associated with complications and side effects, no single treatment optimally and effectively treats hemophilia. Therefore, there is an unmet need for novel and effective treatments that address the shortcomings of FVIII treatment of hemophilia A. [Means for solving the problem]

[0008] The present disclosure provides an isolated antibody or antigen-binding portion thereof ("anti-FIXa antibody or antigen-binding portion thereof") that specifically binds to activated factor IX (FIXa), wherein the anti-FIXa antibody or antigen-binding portion thereof preferentially binds to FIXa in the presence of FIXa and factor IX zymogen (FIXz). In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof binds to FIXa with a higher binding affinity than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof to FIXz. The present disclosure also provides an isolated anti-FIXa antibody or antigen-binding portion thereof that binds to FIXa with a higher binding affinity than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof to FIXz. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, has a K of about 100 nM or less, about 90 nM or less, about 80 nM or less, about 70 nM or less, about 60 nM or less, about 50 nM or less, about 40 nM or less, about 30 nM or less, about 20 nM or less, about 10 nM or less, about 8 nM or less, about 6 nM or less, about 4 nM or less, about 2 nM or less, or about 1 nM or less, as determined by a biolayer interferometry (BLI) assay. Dand binds to FIXa. In some embodiments, the FIXa is free FIXa, FIXa in the tenase complex, or FIXa covalently linked to EGR-CMK (FIXa-SM). In some embodiments, the FIXz comprises inactivatable factor IX (FIXn). In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, cross-competes with a reference antibody selected from the group consisting of the antibodies in Figures 3A, 3B, and 3C. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figures 3A, 3B, and 3C. In some embodiments, such a reference antibody is selected from BIIB-9-484, BIIB-9-440, BIIB-9-882, BIIB-9-460, BIIB-9-433, and any combination thereof. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof binds preferentially to FIXa-SM compared to free FIXa or FIXz and / or binds to FIXa-SM with a higher binding affinity than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof for free FIXa or FIXz. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 3A. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof binds to the same epitope as the reference antibody selected from the group consisting of the antibodies in Figure 3A. In some embodiments, such reference antibody is selected from BIIB-9-484, BIIB-9-440, BIIB-9-460, and any combination thereof. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof cross-competes with FIXa-SM or FIXa-SM. The anti-FIXa antibody or antigen-binding portion thereof binds preferentially to free FIXa compared to FIXz and / or binds to free FIXa with a higher binding affinity than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof for FIXa-SM or FIXz. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof cross-competes with a reference antibody selected from the group consisting of the antibodies in FIG. 3B. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof binds to the same epitope as the reference antibody selected from the group consisting of the antibodies in FIG. 3B. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof binds preferentially to free FIXa or FIXa-SM compared to FIXz and / or binds to free FIXa or FIXa-SM with a higher binding affinity than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof for FIXz. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof cross-competes with a reference antibody selected from the group consisting of the antibodies in FIG. 3C. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figure 3C. In some embodiments, such reference antibody is selected from BIIB-9-882, BIIB-9-433, and a combination thereof. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3, wherein the CDR3 comprises a VH CDR3 selected from the group consisting of a VH CDR3 in Figure 3A, Figure 3B, and Figure 3C, or a VH CDR3 having one or two mutations. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises CDR1, CDR2 and CDR3, wherein CDR3 comprises ARDX1X2X3X4X5X6YYX7MDV (sequence number 753), wherein X1 is V or G, X2 is G or V, X3 is G or R, X4 is Y or V, X5 is A or S, X6 is G or D, and X7 is G or absent.In some embodiments, CDR3 comprises ARDVGGYAGYYGMDV (SEQ ID NO: 905, BIIB-9-484, 1335, 1336), ARDISTDGESSLYYYMDV (SEQ ID NO: 901, BIIB-9-460), ARGPTDSSGYLDMDV (SEQ ID NO: 1186, BIIB-9-882), or ARDGPRVSDYY MDV (SEQ ID NO: 912, BIIB-9-619). In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3, wherein CDR1 comprises a VH CDR1 selected from the group consisting of a VH CDR1 in Figures 3A, 3B, and 3C, or a VH CDR1 with one or two mutations. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, CDR2, and CDR3, wherein CDR2 comprises a VH CDR2 selected from the group consisting of the VH CDR2 in Figures 3A, 3B, and 3C or a VH CDR2 with one or two mutations. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, wherein CDR1 comprises a VL CDR1 selected from the group consisting of the VL CDR1 in Figures 3A, 3B, and 3C or a VL CDR1 with one or two mutations. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, wherein CDR2 comprises a VL CDR2 selected from the group consisting of the VL CDR2 in Figures 3A, 3B, and 3C or a VL CDR2 with one or two mutations. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises a VL CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VL CDR3 selected from the group consisting of a VL CDR3 in Figures 3A, 3B and 3C or a VL CDR3 having one or two mutations.

[0009] The present disclosure also provides an isolated anti-FIXa antibody or antigen-binding portion thereof that specifically binds to FIXa, comprising VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, wherein the VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, respectively, comprise the VH CDR1, VH CDR2, and VH CDR3, and VL CDR1, CDR2, and CDR3 of Figures 3A, 3B, and 3C. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, CDR2, and CDR3, respectively, comprising SEQ ID NOs: 815, 860, and 905. and CDR3 sequences comprising SEQ ID NOs: 950, 995, and 1040, respectively (BIIB-9-484). In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 809, 854, and 899, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NOs: 944, 989, and 1034, respectively (BIIB-9-440). In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NO: 1102, SEQ ID NO: 1144, and SEQ ID NO: 1186, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 1228, SEQ ID NO: 1270, and SEQ ID NO: 1312, respectively (BIIB-9-882). In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NO: 811, SEQ ID NO: 856, and SEQ ID NO: 901, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 946, SEQ ID NO: 991, and SEQ ID NO: 1036, respectively. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NO:1108, SEQ ID NO:1150, and SEQ ID NO:1192, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO:1234, SEQ ID NO:1276, and SEQ ID NO:1318, respectively (BIIB-9-433). In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NO:822, SEQ ID NO:867, and SEQ ID NO:912, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO:957, SEQ ID NO:1002, and SEQ ID NO:1047, respectively (BIIB-9-619). In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises a VH comprising SEQ ID NO: 843, SEQ ID NO: 888, and SEQ ID NO: 933, respectively. or (ii) an anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO:844, SEQ ID NO:889 and SEQ ID NO:934, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO:950, SEQ ID NO:995 and SEQ ID NO:1040, respectively (BIIB-9-1335 and BIIB-9-1336). The anti-FIXa antibody or antigen-binding portion thereof comprises a VH and a VL, wherein the VH is selected from the group consisting of SEQ ID NOs: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125 , 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149, 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, and 181, which are at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99% or about 100% identical to an amino acid sequence selected from the group consisting of: In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein the VL is selected from the group consisting of SEQ ID NOs: 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 295, 297, 299, 301, 303, 305, 307, 309, 311, 313, 315, 317, 319, 321, 323, 325, 327, 329, 331, 333, 335, 337, 339, 341, 343, 345, 347, 349, 351, 353, 355, 357, 359, 361, 363, 365, and 367. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein the VH is derived from the germline sequence of VH1-46.0, VH1-46.4, VH1-46.5, VH1-46.7, VH1-46.9, VH1-69.9, VH3-07.0, VH3-21.0, VH3-21.2, VH3-23.0, VH3-23.1, VH4-31.0, VH4-34.0, VH4-39.0, VH4-39.2, VH4-39.3, VH4-39.5, VH4-39.6, VH4-39.8, VH4-59.6, VH4-0B.4, or VH4-0B.6. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein the VL is selected from the group consisting of VK1-05.0, VK1-05.6, VK1-05.9, VK1-05.21, VK1-12.0, VK1-12.3, VK1-33.0, VK1-33.1, VK1-33.2, VK1-33.8, VK1-33.10, VK1-39.0, VK1-39.6, VK2-28.0, VK2-29.1, VK2-30.1, VK2-31.1, VK2-32.1, VK2-33.2, VK2-33.3, VK2-34.1, VK2-34.2, VK2-34.3, VK2-34.4, VK2-34.5, VK2-34.6, VK2-34.7, VK2-34.8, VK2-34.9, VK2-35.10, VK2-35.11, VK2-35.12, VK2-35.13, VK2-35.14, VK2-35.15, VK2-35.16, VK2-35.17, VK2-35.18, VK2-35.19, VK2-36.21, VK2-36.22, VK2-36.23, VK2-36.24, VK2-36.25, VK2-36.26, VK2-36.27, VK2-36.28, VK2-36.29, VK2-36.30, VK2-36.31 VK3-28.1, VK3-11.0, VK3-11.2, VK3-11.6, VK3-11.10, VK3-11.14, VK3-15.0, VK3-15.6, VK3-15.8, VK3-15.11, VK3-15.20, VK3-15.26, VK3-20.0, VK3-20.4, VK3-20.5, VK3-20.8, or VK4-01.0 germline sequence.In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein (a1) the VH and VL comprise SEQ ID NOs: 31 and 221 (BIIB-9-484), respectively; (a2) the VH and VL comprise SEQ ID NOs: 19 and 209 (BIIB-9-440), respectively; (a3) ​​the VH and VL comprise SEQ ID NOs: 115 and 301 (BIIB-9-882), respectively; (a4) the VH and VL comprise SEQ ID NOs: 23 and 213 (BIIB-9-460), respectively; and (a5) the VH and VL comprise SEQ ID NOs: 127 and 313, respectively (BIIB-9-433); (a6) VH and VL comprise SEQ ID NOs: 45 and 235, respectively (BIIB-9-619); (a7) VH and VL comprise SEQ ID NOs: 185 and 371, respectively (BIIB-9-578); (a8) VH and VL comprise SEQ ID NOs: 87 and 221, respectively (BIIB-9-1335); or (a9) VH and VL comprise SEQ ID NOs: 89 and 221, respectively (BIIB-9-1336).

[0010] The present disclosure also provides an isolated antibody or antigen-binding portion thereof that specifically binds to FIXz ("anti-FIXz antibody or antigen-binding portion thereof"), wherein the anti-FIXz antibody or antigen-binding portion thereof preferentially binds to FIXz in the presence of free FIXa or FIXa-SM and / or the anti-FIXz antibody or antigen-binding portion thereof binds to FIXz with a higher binding affinity than the binding affinity of the anti-FIXz antibody or antigen-binding portion thereof to free FIXa or FIXa-SM. In some embodiments, the anti-FIXz antibody or antigen-binding portion thereof cross-competes with a reference antibody selected from the group consisting of the antibodies in FIG. 3D. In some embodiments, the anti-FIXz antibody or antigen-binding portion thereof binds to the same epitope as the reference antibody selected from the group consisting of the antibodies in FIG. 3D. In some embodiments, such a reference antibody is BIIB-9-578. In some embodiments, the anti-FIXz antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3, wherein the CDR3 comprises a VH CDR3 selected from the group consisting of a VH CDR3 in Figure 3D or a VH CDR3 with one or two mutations. In some embodiments, the CDR3 comprises ARDKYQDYSFDI (SEQ ID NO: 1355, BIIB-9-578). In some embodiments, the anti-FIXz antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3. R3, and CDR1 comprises a VH CDR1 selected from the group consisting of the VH CDR1 in Figure 3D or a VH CDR1 with one or two mutations. In some embodiments, the anti-FIXz antibody, or antigen-binding portion thereof, comprises a VH CDR1, CDR2, and CDR3, and CDR2 comprises a VH CDR2 selected from the group consisting of the VH CDR2 in Figure 3D or a VH CDR2 with one or two mutations. In some embodiments, the anti-FIXz antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, and CDR1 comprises a VL CDR1 selected from the group consisting of the VL CDR1 in Figure 3D or a VL CDR1 with one or two mutations. In some embodiments, the anti-FIXz antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, and CDR2 comprises a VL CDR2 selected from the group consisting of the VL CDR2 in Figure 3D or a VL CDR2 with one or two mutations. In some embodiments, the anti-FIXz antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, wherein the CDR3 comprises a VL CDR3 selected from the group consisting of the VL CDR3 in Figure 3D or a VL CDR3 with one or two mutations. In some embodiments, the anti-FIX antibody is selected from the group consisting of IgG1, IgG2, IgG3, IgG4, or variants thereof. In some embodiments, the anti-FIX antibody is an IgG4 antibody. In some embodiments, the anti-FIX antibody comprises an effectorless IgG4 Fc. In some embodiments, the anti-FIX antibody, or antigen-binding portion thereof, comprises a heavy chain constant region. In some embodiments, the anti-FIX antibody is a human antibody, an engineered antibody, or a humanized antibody. In some embodiments, the anti-FIX antigen-binding portion comprises a Fab, a Fab', a F(ab')2, an Fv, or a single-chain Fv (scFv).

[0011] The present disclosure also provides bispecific molecules comprising an anti-FIX antibody, or antigen-binding portion thereof, disclosed herein linked to a molecule having a second binding specificity. Nucleic acids encoding the heavy and / or light chain variable regions of an anti-FIX antibody, or antigen-binding portion thereof, disclosed herein, or bispecific molecules comprising an anti-FIX antibody, or antigen-binding portion thereof, disclosed herein are also provided. Expression vectors comprising the encoding nucleic acid molecules disclosed herein are also provided. Cells transformed with the expression vectors disclosed herein are also provided. The present disclosure also provides immunoconjugates comprising any antibody, or antigen-binding portion thereof, or bispecific molecule disclosed herein, linked to an agent. The present disclosure also provides compositions comprising (i) an antibody, or antigen-binding portion thereof, disclosed herein, a bispecific molecule disclosed herein, or an immunoconjugate disclosed herein, and (ii) a carrier. Similarly, provided are kits comprising (i) an antibody or antigen-binding portion thereof disclosed herein, a bispecific molecule disclosed herein, or an immunoconjugate disclosed herein, and (ii) instructions for use.

[0012] The present disclosure also provides a method for producing an anti-FIX antibody or antigen-binding portion thereof, comprising expressing the antibody or antigen-binding portion thereof in cells and isolating the antibody or antigen-binding portion thereof from the cells. Similarly, a method for measuring the level of activated FIX in a subject in need thereof is provided, comprising contacting a sample obtained from the subject with an anti-FIXa antibody or antigen-binding portion thereof disclosed herein under suitable conditions and measuring the binding of the anti-FIXa antibody or antigen-binding portion thereof to FIXa in the sample. In some embodiments, the sample is blood or serum.

[0013] The present disclosure provides an isolated antibody or antigen-binding portion thereof that specifically binds to factor X zymogen (FXz) ("anti-FXz antibody or antigen-binding portion thereof"), wherein the anti-FXz antibody or antigen-binding portion thereof preferentially binds to FXz in the presence of FXz and activated factor X (FXa). In some embodiments, The anti-FXz antibody or antigen-binding portion thereof binds to FXz with a higher binding affinity than the antibody or antigen-binding portion thereof to FXa. Similarly, an isolated anti-FXz antibody or antigen-binding portion thereof is provided that binds to FXz with a higher binding affinity than the antibody or antigen-binding portion thereof to FXa. In some embodiments, the anti-FXz antibody or antigen-binding portion thereof has a K of about 100 nM or less, about 90 nM or less, about 80 nM or less, about 70 nM or less, about 60 nM or less, about 50 nM or less, about 40 nM or less, about 30 nM or less, about 20 nM or less, about 10 nM or less, about 9 nM or less, about 8 nM or less, about 7 nM or less, about 6 nM or less, about 5 nM or less, about 4 nM or less, about 3 nM or less, about 2 nM or less, or about 1 nM or less, as measured by BLI. Dand binds to FXz. In some embodiments, the FXa is free FXa or FXa covalently linked to EGR-CMK (FIXa-SM). In some embodiments, the FXz comprises inactivatable factor X (FXn). In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, cross-competes with a reference antibody selected from the group consisting of the antibodies in Figures 12A and 12B. In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figures 12A and 12B. In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, binds to the same epitope as a reference antibody selected from the group consisting of BIIB-12-915, BIIB-12-917, BIIB-12-932, and any combination thereof. In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3, wherein the CDR3 comprises a VH CDR3 selected from the group consisting of the VH CDR3s in Figure 12A and Figure 12 or a VH CDR3 having one or two mutations. In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3, wherein the CDR3 comprises ARX1X2X3RX4X5X6X7FDX8 (SEQ ID NO: 766), wherein X1 is G or L, X2 is R or G, X3 is F or Y, X4 is P or G, X5 is R or A, X6 is G or S, X7 is R or A, and X8 is Y or I. In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3, wherein CDR3 comprises ARGRFRPRGRFDY (SEQ ID NO: 1575, BIIB-12-917), ARLGYRGASAFDI (SEQ ID NO: 1589, BIIB-12-932), or ARVGGGYANP (SEQ ID NO: 1573, BIIB-12-915). In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises VH CDR1, CDR2, and CDR3, wherein CDR1 comprises a VH CDR1 selected from the group consisting of the VH CDR1 in Figures 12A and 12B or a VH CDR1 with one or two mutations.In some embodiments, an anti-FXz antibody, or antigen-binding portion thereof, comprises a VH CDR1, CDR2, and CDR3, wherein CDR2 comprises a VH CDR2 selected from the group consisting of the VH CDR2 in Figures 12A and 12B or a VH CDR2 with one or two mutations. In some embodiments, an anti-FXz antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, wherein CDR1 comprises a VL CDR1 selected from the group consisting of the VL CDR1 in Figures 12A and 12B or a VL CDR1 with one or two mutations. In some embodiments, an anti-FXz antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, wherein CDR2 comprises a VL CDR2 selected from the group consisting of the VL CDR2 in Figures 12A and 12B or a VL CDR2 with one or two mutations. In some embodiments, the anti-FXz antibody or antigen-binding portion thereof comprises a VL CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VL CDR3 selected from the group consisting of a VL CDR3 in Figures 12A and 12B or a VL CDR3 having one or two mutations.

[0014] The present disclosure also provides an isolated antibody or antigen-binding portion thereof that specifically binds to FXz, comprising a VH CDR1, CDR2, and CDR3, and a VL CDR1, CDR2, and CDR3, wherein the VH CDR1, CDR2, and CDR3, and the VL CDR1, CDR2, and CDR3, are shown in Figures 12A and 12B, respectively. , CDR2 and CDR3, and VL CDR1, CDR2 and CDR3. In some embodiments, an anti-FXz antibody, or antigen-binding portion thereof, comprises a VH CDR1, CDR2 and CDR3 sequence comprising SEQ ID NO: 1393, 1483, or 1573, respectively, and / or a VL CDR1, VL CDR2 and VL CDR3 sequence comprising SEQ ID NO: 1663, 1753, and 1843, respectively (BIIB-12-915). In some embodiments, an anti-FXz antibody, or antigen-binding portion thereof, comprises a VH CDR1, CDR2 and CDR3 sequence comprising SEQ ID NO: 1395, 1485, or 1575, respectively, and / or a VL CDR1, VL CDR2 and VL CDR3 sequence comprising SEQ ID NO: 1665, 1755, and 1845, respectively (BIIB-12-917). In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises a VH CDR1, CDR2, and CDR3 sequence comprising SEQ ID NOs: 1409, 1499, or 1589, respectively, and / or a VL CDR1, VL CDR2, and VL CDR3 sequence comprising SEQ ID NOs: 1679, 1769, and 1859, respectively. Contains the CDR2 and VL CDR3 sequence (BIIB-12-932). In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein the VH is selected from the group consisting of SEQ ID NOs: 377, 379, 381, 383, 385, 387, 389, 391, 393, 395, 397, 399, 401, 403, 405, 407, 409, 411, 413, 415, 417, 419, 421, 423, 425, 427, 429, 431, 433, 435, 437, 439, 441, 443, 445, 447, 449, 451, 453, 455, 457, 459, 461, 463, 465, 467, 469, 471, 473, 475, 477, 479, 481, 483, 484, 485, 486, 487, 488, 489, 490, 500, 501, 502, 503, 504, 505, 506, 507, 508, 509, 510, 511, 512, 513, 514, 515, 516, 517, 518, 519, 520, 521, 522, 523, 524, 525, 526, 527, 528, 529, 530, 531, 5 5, 487, 489, 491, 493, 495, 497, 499, 501, 503, 505, 507, 509, 511, 513, 515, 517, 519, 521, 523, 525, 527, 529, 531, 533, 535, 537, 539, 541, 543, 545, 547, 549, 551, 553, and 555.In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein the VL is selected from the group consisting of SEQ ID NOs: 565, 567, 569, 571, 573, 575, 579, 581, 583, 585, 587, 589, 591, 593, 595, 597, 599, 601, 603, 605, 607, 609, 611, 613, 615, 617, 619, 621, 623, 625, 627, 629, 631, 633, 635, 637, 639, 641, 643, 645, 647, 649, 651, 653, 655, 657, 659, 661, 663, 665, 667, 669, 671, 673, 731, 733, 735, 737, 739, 741, and 743. In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein the VH is derived from the germline sequence of VH1-18.0, VH1-18.1, VH1-18.8, VH1-46.0, VH1-46.4, VH1-46.5, VH1-46.6, VH1-46.7, VH1-46.8, VH1-46.9, VH3-21.0, VH3-23.0, VH3-23.2, VH3-23.6, VH3-30.0, VH4-31.5, VH4-39.0, VH4-39.5, VH4-0B.4, or VH5-51.1. In some embodiments, the anti-FXz antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein the VL is VK1-05.6, VK1-05.12, VK1-12.0, VK1-12.4, VK1-12.7, VK1-12.10, VK1-12.15, VK1-39.0, VK1-39.3, VK1-39.15, VK2-28.0, VK2-28.1, VK2-28.5, VK3-11.0, VK3-11.2, VK3-11.6, VK3-11. VK4-01.0, VK4-01.4, VK4-01.20. In some embodiments, the anti-FX antibody or antigen-binding portion thereof comprises a VH and a VL, wherein (b1) the VH and VL comprise SEQ ID NOs: 423 and 611, respectively (BIIB-12-915); (b2) the VH and VL comprise SEQ ID NOs: 427 and 615, respectively (BIIB-12-917); or (b3) the VH and VL comprise SEQ ID NOs: 455 and 643, respectively (BIIB-12-932).

[0015] The present disclosure also provides an isolated antibody or antigen-binding portion thereof that specifically binds to activated factor X (FXa) ("anti-FXa antibody or antigen-binding portion thereof"), wherein the anti-FXa antibody or antigen-binding portion thereof preferentially binds to FXa in the presence of FXz and FXa and / or binds to FXa with a higher binding affinity than the binding affinity of the antibody or antigen-binding portion thereof to FXz. In some embodiments, the anti-FXa antibody or antigen-binding portion thereof cross-competes with a reference antibody selected from the group consisting of the antibodies in FIG. 12C. In some embodiments, the anti-FXa antibody or antigen-binding portion thereof binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in FIG. 12C. In some embodiments, the anti-FXa antibody or antigen-binding portion thereof binds to the same epitope as a reference antibody selected from the group consisting of BIIB-12-925. In some embodiments, the anti-FXa antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3, wherein the CDR3 comprises a VH CDR3 selected from the group consisting of the VH CDR3 in Figure 12C or a VH CDR3 with one or two mutations. In some embodiments, the anti-FXa antibody, or antigen-binding portion thereof, comprises CDR1, CDR2, and CDR3, wherein the CDR3 comprises AKGPRYYWYSWYFDL (SEQ ID NO: 1919, BIIB-12-925). In some embodiments, the anti-FXa antibody, or antigen-binding portion thereof, comprises VH CDR1, CDR2, and CDR3, wherein the CDR1 comprises a VH CDR1 selected from the group consisting of the VH CDR1 in Figure 12C or a VH CDR1 with one or two mutations. In some embodiments, the anti-FXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, CDR2, and CDR3, wherein CDR2 comprises a VH CDR2 selected from the group consisting of the VH CDR2 in Figure 12C or a VH CDR2 with one or two mutations. In some embodiments, the anti-FXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, wherein CDR1 comprises a VH CDR1 selected from the group consisting of the VH CDR1 in Figure 12C or a VH CDR1 with one or two mutations.In some embodiments, the anti-FXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, wherein CDR2 comprises a VL CDR2 selected from the group consisting of the VL CDR2 in Figure 12C or a VL CDR2 with one or two mutations. In some embodiments, the anti-FXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, CDR2, and CDR3, wherein CDR3 comprises a VL CDR3 selected from the group consisting of the VL CDR3 in Figure 12C or a VL CDR3 with one or two mutations.

[0016] The present disclosure also provides an isolated antibody or antigen-binding portion thereof that specifically binds to FXa, comprising a VH CDR1, CDR2, and CDR3, and a VL CDR1, CDR2, and CDR3, wherein the VH CDR1, CDR2, and CDR3 and the VL CDR1, CDR2, and CDR3 comprise the VH CDR1, CDR2, and CDR3 and VL CDR1, CDR2, and CDR3, respectively, of Figure 12C. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises a VH CDR1, CDR2, and CDR3 sequence comprising SEQ ID NO: 1911, 1915, or 1919, respectively, and / or a VL CDR1, VL CDR2, and VL CDR3 sequence comprising SEQ ID NO: 1923, 1927, or 1931, respectively (BIIB-12-925). In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises a VH and a VL, wherein the VH and VL are The antibodies include SEQ ID NOs: 559 and 747 (BIIB-12-925), respectively. In some embodiments, the anti-FX antibody or antigen-binding portion thereof is selected from the group consisting of IgG1, IgG2, IgG3, IgG4, or variants thereof. In some embodiments, the anti-FX antibody or antigen-binding portion thereof is an IgG4 antibody. In some embodiments, the anti-FX antibody or antigen-binding portion thereof comprises an effector-less IgG4 Fc. In some embodiments, the anti-FX antibody or antigen-binding portion thereof comprises a heavy chain constant region. In some embodiments, the anti-FX antibody is a human antibody, an engineered antibody, or a humanized antibody. In some embodiments, the antigen-binding portion thereof comprises a Fab, Fab', F(ab')2, Fv, or single-chain Fv (scFv). The present disclosure also provides bispecific molecules comprising an anti-FX antibody disclosed herein linked to a molecule having a second binding specificity. Similarly, nucleic acids encoding the heavy and / or light chain variable regions of an anti-FX antibody or antigen-binding portion thereof disclosed herein, or a bispecific molecule comprising an anti-FX antibody or antigen-binding portion thereof disclosed herein, are provided. Similarly, an expression vector comprising the nucleic acid molecule is provided. Similarly, a cell transformed with the expression vector is provided. Similarly, an immunoconjugate comprising an antibody or antigen-binding portion thereof, or a bispecific molecule, linked to an agent is provided. Similarly, a composition comprising (i) an antibody or antigen-binding portion thereof, or a bispecific molecule, or an immunoconjugate, and (ii) a carrier is provided. Similarly, a kit comprising (i) an antibody or antigen-binding portion thereof, or a bispecific molecule, or an immunoconjugate, and (ii) instructions for use is provided. Similarly, a method for producing an anti-FX antibody or antigen-binding portion thereof is provided, the method comprising expressing the antibody or antigen-binding portion thereof in a cell and isolating the antibody or antigen-binding portion thereof from the cell.

[0017] The present disclosure also provides a method for measuring zymogen FX (FXz) in a subject in need thereof, comprising contacting an anti-FX antibody, or antigen-binding portion thereof, disclosed herein with a sample obtained from the subject under suitable conditions and measuring binding of the anti-FX antibody, or antigen-binding portion thereof, to FXz in the sample. In some embodiments, the sample is blood or serum from the subject. The present disclosure also provides a bispecific molecule comprising (i) an anti-FIX antibody, or antigen-binding portion thereof, disclosed herein, and (ii) an anti-FX antibody, or antigen-binding portion thereof, disclosed herein. In some embodiments, the bispecific molecule cross-competes with a reference bispecific antibody, wherein the reference bispecific antibody comprises the VH and VL of an anti-FIX antibody selected from the group consisting of the anti-FIX antibodies in Figures 3A, 3B, 3C, and 3D, and the VH and VL of an anti-FX antibody selected from the group consisting of the anti-FX antibodies in Figures 12A, 12B, and 12C. In some embodiments, the bispecific molecule binds to the same epitope as a reference bispecific antibody, wherein the reference bispecific antibody comprises the VH and VL of an anti-FIX antibody selected from the group consisting of the anti-FIX antibodies in Figures 3A, 3B, 3C, and 3D, and the VH and VL of an anti-FX antibody selected from the group consisting of the anti-FX antibodies in Figures 12A, 12B, and 12C.In some embodiments of the bispecific molecules disclosed herein, (i) the anti-FIX antibody, or antigen-binding portion thereof, comprises VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, wherein the VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3 are selected from the group consisting of VH CDR1, VH CDR2, and VH CDR3, and VL CDR1, VL CDR2, and VL CDR3 of the anti-FIX (BIIB-9) antibody in Figures 16A, 16B, 16C, and 16D; and (ii) the anti-FX antibody, or antigen-binding portion thereof, comprises VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, wherein the VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3 are selected from the group consisting of VH CDR1, VH CDR2, and VH CDR3, and VL CDR1, VL CDR2, and VL CDR3 of the anti-FIX (BIIB-9) antibody in Figures 16A, 16B, 16C, and 16D. CDR1, CDR2, and CDR3 are selected from the group consisting of VH CDR1, VH CDR2, and VH CDR3 and VL CDR1, VL CDR2, and VL CDR3 of anti-FX (BIIB-12) antibody in Figures 16A, 16B, 16C, and 16D. In some embodiments of the bispecific molecules disclosed herein. (a) an anti-FIX antibody or antigen-binding portion thereof, comprising: (a1) a VH CDR1, CDR2, and CDR3 sequence comprising SEQ ID NO: 815, 860, or 905, respectively, and / or a VL CDR1, VL CDR2, and VL CDR3 sequence comprising SEQ ID NO: 950, 995, or 1040, respectively (BIIB-9-484); (a2) a VH CDR1, CDR2, and CDR3 sequence comprising SEQ ID NO: 822, 867, and 912, respectively, and / or a VL CDR1, CDR2, and CDR3 sequence comprising SEQ ID NO: 957, 1002, and 1047, respectively (BIIB-9-619); (a3) ​​a VH CDR1, CDR2, and CDR3 sequence comprising SEQ ID NO: 1347, 1351, and 1355, respectively, and / or a VL CDR1, CDR2, and CDR3 sequence comprising SEQ ID NO: 1359, 1363, and 1367, respectively. (a1) a VH CDR1, CDR2, and CDR3 sequence comprising SEQ ID NOs: 843, 888, and 933, respectively, and / or a VL CDR1, CDR2, and CDR3 sequence comprising SEQ ID NOs: 978, 1023, and 1068, respectively (BIIB-9-1335); or (a5) a VH CDR1, CDR2, and CDR3 sequence comprising SEQ ID NOs: 844, 889, and 934, respectively, and / or a VL CDR1, CDR2, and CDR3 sequence comprising SEQ ID NOs: 979, 1024, and 1069, respectively (BIIB-9-1336); (b) an anti-FX antibody or antigen-binding portion thereof comprising (b1) a VH CDR1, CDR2, and CDR3 sequence comprising SEQ ID NOs: 1393, 1483, and 1573, respectively. (b2) VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NOs: 1395, 1485 and 1575, respectively, and / or VL CDR1, CDR2 and CDR3 sequences comprising SEQ ID NOs: 1665, 1755 and 1845, respectively (BIIB-12-917);(b3) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1911, 1915, and 1919, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1923, 1927, and 1931, respectively (BIIB-12-925); (b4) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1409, 1499, and 1589, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1679, 1769, and 1859, respectively (BIIB-12-932); or (b5) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1433, 1523, and 1613, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1703, 1793, and 1883, respectively. In some embodiments of the bispecific molecules disclosed herein, (a) the anti-FIX antibody, or antigen-binding portion thereof, comprises: (a1) a VH and VL comprising SEQ ID NOs: 31 and 221, respectively (BIIB-9-484); (a2) a VH and VL comprising SEQ ID NOs: 45 and 235, respectively (BIIB-9-619); (a3) ​​a VH and VL comprising SEQ ID NOs: 185 and 371, respectively (BIIB-9-578); (a4) a VH and VL comprising SEQ ID NOs: 87 and 221, respectively (BIIB-9-1335); or (a5) a VH and VL comprising SEQ ID NOs: 185 and 371, respectively (BIIB-9-578). (b) an anti-FX antibody or antigen-binding portion thereof, comprising: (b1) a VH and VL comprising SEQ ID NOs: 423 and 611, respectively (BIIB-12-915); (b2) a VH and VL comprising SEQ ID NOs: 427 and 615, respectively (BIIB-12-917); (b3) a VH and VL comprising SEQ ID NOs: 559 and 747, respectively (BIIB-12-925); (b4) a VH and VL comprising SEQ ID NOs: 455 and 643, respectively (BIIB-12-932);or (b5) comprises a VH and a VL (BIIB-12-1306) comprising, respectively, SEQ ID NOs: 503 and 691. In some embodiments of the bispecific molecules disclosed herein, (i) the anti-FIX antibody, or antigen-binding portion thereof, comprises a VH and a VL (BIIB-9-484) comprising, respectively, SEQ ID NOs: 31 and 221; and the anti-FX antibody, or antigen-binding portion thereof, comprises a VH and a VL (BIIB-12-915) comprising, respectively, SEQ ID NOs: 423 and 611; and (ii) the anti-FIX antibody or antigen-binding portion thereof comprises a VH and VL (BIIB-9-484) comprising SEQ ID NOs: 31 and 221, respectively; the anti-FX antibody or antigen-binding portion thereof comprises a VH and VL (BIIB-12-917) comprising SEQ ID NOs: 427 and 615, respectively; or (iii) the anti-FIX antibody or antigen-binding portion thereof comprises a VH and VL (BIIB-9-484) comprising SEQ ID NOs: 31 and 221, respectively; the anti-FX antibody or antigen-binding portion thereof comprises a VH and VL (BIIB-9-484) comprising SEQ ID NOs: 559 and 615, respectively. and 747 (BIIB-12-925); or (iv) an anti-FIX antibody, or antigen-binding portion thereof, comprising a VH and VL comprising SEQ ID NOs: 31 and 221, respectively (BIIB-9-484); an anti-FX antibody, or antigen-binding portion thereof, comprising a VH and VL comprising SEQ ID NOs: 455 and 643, respectively (BIIB-12-932); or (v) an anti-FIX antibody, or antigen-binding portion thereof, comprising a VH and VL comprising SEQ ID NOs: 185 and 371, respectively (BIIB-9-578); (vi) an anti-FIX antibody or antigen-binding portion thereof comprises a VH and VL comprising SEQ ID NOs: 185 and 371, respectively (BIIB-9-578); an anti-FX antibody or antigen-binding portion thereof comprises a VH and VL comprising SEQ ID NOs: 427 and 615, respectively (BIIB-12-917); or (vii) an anti-FIX antibody or antigen-binding portion thereof comprises a VH and VL comprising SEQ ID NOs: 427 and 615, respectively (BIIB-12-917). the anti-FX antibody or antigen-binding portion thereof comprises a VH and VL (BIIB-9-619) comprising SEQ ID NOs: 5 and 235, respectively; the anti-FX antibody or antigen-binding portion thereof comprises a VH and VL (BIIB-12-917) comprising SEQ ID NOs: 427 and 615, respectively; or (viii) the anti-FIX antibody or antigen-binding portion thereof comprises a VH and VL (BIIB-9-619) comprising SEQ ID NOs: 45 and 235, respectively; and the anti-FX antibody or antigen-binding portion thereof comprises a VH and VL (BIIB-12-925) comprising SEQ ID NOs: 559 and 747, respectively.In some embodiments, the bispecific molecule functionally mimics activated factor VIII (FVIIIa) cofactor in at least one FVIIIa activity assay. In some embodiments, the FVIIIa activity assay is selected from a chromogenic FXa generation assay, a one-stage clotting assay, or a combination thereof. In some embodiments, the FVIIIa activity achieves at least 10%, 20%, 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, 90%, 100%, 110%, 120%, 130%, 140%, 150%, 160%, 170%, 180%, 190%, or 200% of the activity normally achieved by FVIII in the same assay. In some embodiments, the bispecific molecule is capable of generating thrombin from prothrombin, fibrin from fibrinogen, and / or a fibrin clot in vitro or in vivo. In some embodiments, the bispecific molecule simultaneously binds to both FIXa and FX as determined by BLI. In some embodiments, the bispecific molecule is of the IgG isotype. In some embodiments, the IgG isotype is of the IgG1 part class. In some embodiments, the IgG isotype is of the IgG4 part class. In some embodiments, the bispecific molecule is of a bispecific IgG format and is selected from the group consisting of the antibodies in Table 2. In some embodiments, the bispecific molecule is of a bispecific heterodimer format. In some embodiments, the bispecific molecule comprises two different heavy chains and two different light chains. In some embodiments, the bispecific molecule comprises two identical light chains and two different heavy chains. In some embodiments, the bispecific molecule is capable of controlling or reducing the incidence of bleeding episodes in subjects with hemophilia. In some embodiments, the bispecific molecule can maintain homeostasis in subjects with hemophilia. In some embodiments, the bispecific molecule can provide routine prophylaxis in subjects with hemophilia. In some embodiments, the subject develops or is expected to develop neutralizing antibodies against Factor VIII.

[0018] The present disclosure also provides immunoconjugates comprising the bispecific molecules disclosed herein linked to an agent, e.g., a therapeutic agent. Compositions are provided that include an immunoconjugate comprising a bispecific or bispecific molecule and (ii) a carrier. Similarly, kits are provided that include (i) a bispecific or bispecific molecule disclosed herein or an immunoconjugate comprising a bispecific molecule, and (ii) instructions for use. Similarly, nucleic acid sequences encoding the bispecific molecules disclosed herein are provided. Similarly, vectors comprising the nucleic acids and host cells comprising the vectors are provided. In some embodiments, the host cell is a prokaryotic cell, a eukaryotic cell, a protist cell, an animal cell, a plant cell, a fungal cell, a yeast cell, an Sf9 cell, a mammalian cell, an avian cell, an insect cell, a CHO cell, an HEK cell, or a COS cell. Also provided are methods of producing the bispecific molecules disclosed herein, comprising culturing the host cells disclosed herein under conditions that allow expression of the bispecific molecules. In some embodiments, the methods of producing the bispecific molecules disclosed herein further include using conditions that enhance heterodimerization.

[0019] The present disclosure also provides a method of promoting FX activation in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of a bispecific molecule disclosed herein, or an immunoconjugate, composition, nucleic acid, vector, or host cell disclosed herein comprising or encoding a bispecific molecule disclosed herein.

[0020] The present disclosure also provides methods of reducing the frequency or severity of bleeding episodes in a subject in need thereof, comprising administering to the subject an effective amount of a bispecific molecule disclosed herein, or an immunoconjugate, composition, nucleic acid, vector, or host cell disclosed herein comprising or encoding a bispecific molecule disclosed herein. In some embodiments, the subject develops or is prone to develop an inhibitor of Factor VIII ("FVIII"). In some embodiments, the inhibitor of FVIII is a neutralizing antibody to FVIII. In some embodiments, the bleeding episode is the result of a hemarthrosis, muscle bleeding, oral bleeding, bleeding, bleeding into muscle, oral bleeding, trauma, head trauma, gastrointestinal bleeding, intracranial bleeding, intra-abdominal bleeding, intrathoracic bleeding, fracture, central nervous system bleeding, bleeding in the retropharyngeal space, bleeding in the retroperitoneal space, bleeding in the iliopsoas sheath, or any combination thereof.

[0021] The present disclosure also provides a method of treating a blood clotting disorder in a subject in need thereof, comprising administering to the subject an effective amount of a bispecific molecule disclosed herein, or an immunoconjugate, composition, nucleic acid, vector, or host cell comprising or encoding a bispecific molecule disclosed herein. In some embodiments, the blood clotting disorder is hemophilia A or hemophilia B. In some embodiments, the subject is a human subject. In some embodiments, the subject is undergoing or is receiving FVIII replacement therapy. In some embodiments, the bispecific molecule is administered in combination with hemophilia therapy. In some embodiments, the hemophilia therapy is FVIII replacement therapy. In some embodiments, the bispecific molecule, immunoconjugate, composition, nucleic acid, vector, or host cell is administered before, during, or after administration of hemophilia therapy. In some embodiments, the bispecific molecule, immunoconjugate, composition, nucleic acid, vector, or host cell is administered intravenously or subcutaneously. In some embodiments, administration of the bispecific molecule, immunoconjugate, composition, nucleic acid, vector, or host cell reduces the occurrence of bleeding episodes, the frequency of spontaneous bleeding episodes, or acute bleeding, hi some embodiments, administration of the bispecific molecule, immunoconjugate, composition, nucleic acid, vector, or host cell reduces the annualized bleeding rate by 5%, 10%, 20%, 30%, or 50%.

[0022] The present disclosure also provides anti-FIXa antibodies, or antigen-binding portions thereof, that bind to the same epitope as BIIB-9-1336. Similarly, anti-FIXa antibodies, or antigen-binding portions thereof, that bind to an epitope that overlaps with the BIIB-9-1336 epitope are provided.

[0023] The present disclosure also provides anti-FIXa antibodies, or antigen-binding portions thereof, that bind to an epitope region comprising at least one amino acid located between positions (i) 91 and 101, (ii) 125 and 128, (iii) 165 and 179, or (iv) 232 and 241, according to the chymotrypsinogen numbering system, in the sequence of the heavy chain of FIXa. Similarly, provided are anti-FIXa antibodies, or antigen-binding portions thereof, that bind to an epitope comprising at least one of amino acid residues H91, H92, N93, H101, D125, K126, E127, Y128, R165, Y177, N178, N179, S232, R233, Y234, V235, N236, W237, E240, and K241, according to the chymotrypsinogen numbering system, in the sequence of the heavy chain of FIXa. In some embodiments, the epitope comprises amino acid residues N93, R165, N178, and R233 according to chymotrypsinogen numbering of the heavy chain sequence of FIXa. In other embodiments, the epitope comprises amino acid residues H91, H92, N93, H101, D125, K126, E127, Y128, R165, Y177, N178, N179, S232, R233, Y234, V235, N236, W237, E240, and K241 according to chymotrypsinogen numbering of the heavy chain sequence of FIXa. In some embodiments, the epitope does not include at least one of amino acid residues N100, K132, Y137, R170, T172, F174, T175, H185, E202, and G205 of the heavy chain sequence of FIXa according to chymotrypsinogen numbering. In some embodiments, the epitope does not include amino acid residues N100, K132, Y137, R170, T172, F174, T175, H185, E202, and G205 of the heavy chain sequence of FIXa according to chymotrypsinogen numbering. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof binds to at least one amino acid residue in the light chain of FIXa (SEQ ID NO: 756). In some embodiments, the amino acid residue in the light chain of FIXa (SEQ ID NO: 756) is K100. In some embodiments, the epitope overlaps with the binding site of FVIIIa for FIXa. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof cross-competes with FVIIIa for binding to FIXa.In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof blocks binding of FVIIIa to FIXa.

[0024] In some embodiments, an anti-FIXa antibody, or antigen-binding portion thereof, disclosed herein that specifically binds to FIXa comprises a VH CDR1, CDR2, and CDR3, and a VL CDR1, CDR2, and CDR3, wherein (i) the VH CDR1 comprises a VH CDR1 selected from the group consisting of a VH CDR1 in Table 7 or a VH CDR1 with one or two mutations; and / or (ii) the VH CDR2 comprises a VH CDR2 selected from the group consisting of a VH CDR2 in Table 7 or a VH CDR2 with one or two mutations; and / or (iii) the VH CDR3 comprises a VH CDR3 selected from the group consisting of a VH CDR3 in Table 7 or a VH CDR3 with one or two mutations; and / or (iv) the VL CDR1 comprises a VL CDR1 selected from the group consisting of a VL CDR1 in Table 7 or a VL CDR1 with one or two mutations; and / or (v) the VL (vi) the CDR2 comprises a VL CDR2 selected from the group consisting of a VL CDR2 in Table 7 or a VL CDR2 having one or two mutations; and / or (vi) the VL CDR3 comprises a VL CDR3 selected from the group consisting of a VL CDR3 in Table 7 or a VL CDR3 having one or two mutations.

[0025] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises a VH CDR1, CDR2, and CDR3, and a VL CDR1, CDR2, and CDR3, wherein the VH CDR3 comprises the amino acid sequence ARDX1GGYAGYYGMDV (SEQ ID NO: 2196), and X1 is L or V. In some embodiments, (i) the VH CDR1 comprises the amino acid sequence FTFX1SX2X3MX4 (sequence and / or (ii) VH CDR2 comprises the amino acid sequence X5ISX6X7X8X9X 10 X5 is S, A, Y, or G; X6 is S or A; X7 is S, A, or G; X8 is S, G, or D; X9 is S, T, or G; and X 10 is Y or T.

[0026] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises a VL CDR1, CDR2, and CDR3, wherein the VL CDR3 comprises the amino acid sequence QQYANFPYT (SEQ ID NO: 2168). In some embodiments, (i) the VL CDR1 comprises the amino acid sequence QASQDIANYLN (SEQ ID NO: 2116); and / or (ii) the VL CDR2 comprises the amino acid sequence DASNLET (SEQ ID NO: 2142).

[0027] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises (i) a VH CDR1, CDR2, and CDR3, wherein the VH CDR1 is selected from SEQ ID NOs: 2038-2047, the VH CDR2 is selected from SEQ ID NOs: 2064-2073, and the VH CDR3 is selected from SEQ ID NOs: 2090-2099, and / or (ii) a VL CDR1, CDR2, and CDR3, wherein the VL CDR1 is selected from SEQ ID NOs: 2116-2125, the VL CDR2 is selected from SEQ ID NOs: 2142-2151, and the VL CDR3 is selected from SEQ ID NOs: 2168-2177.

[0028] In some embodiments, an anti-FIXa antibody, or antigen-binding portion thereof, disclosed herein that specifically binds to FIXa comprises a VH CDR1, CDR2, and CDR3, and a VL CDR1, CDR2, and CDR3, wherein the VH CDR3 comprises the amino acid sequence X1RDVX2GYAGX3YGMDV (SEQ ID NO: 2198), where X1 is A or V, X2 is G or S, and X3 is Y or F. In some embodiments, (i) the VH CDR1 comprises the amino acid sequence FTFGSYDMN (SEQ ID NO: 2048); and / or (ii) the VH CDR2 comprises the amino acid sequence SISX1X2X3SYIX4YAX5SVKG (SEQ ID NO: 2197), where X1 is S or D, X2 is G or S, X3 is E or A, X4 is Y or A, and X5 is E or D.

[0029] In some aspects, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, wherein VL CDR3 comprises the amino acid sequence X1QYAX2FPYT (sequence number 2201), wherein X1 is Q or S, and X2 is N or R. In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises VL CDR1, CDR2 and CDR3, wherein (i) VL CDR1 comprises the amino acid sequence X1AX2X3X4IX5X6YLN (sequence number 2199), where X1 is Q, G or E, X2 is S or N, X3 is Q or E, X4 is D or Y, X5 is A or S, and X6 is N or D; and / or (ii) VL CDR2 comprises the amino acid sequence DAX7NLX8X9 (sequence number 2200), where X7 is S or A, X8 is E, H or Q, and X9 is T or Y.

[0030] In some embodiments, the anti-FIXa antibodies or antigen-binding portions thereof disclosed herein that specifically bind to FIXa comprise (i) a VH CDR1, CDR2, and CDR3, comprising: and / or (ii) VL CDR1, CDR2 and CDR3, wherein the VL CDR1 is selected from SEQ ID NOs: 2048 to 2052, the VL CDR2 is selected from SEQ ID NOs: 2074 to 2078, and the VL CDR3 is selected from SEQ ID NOs: 2100 to 2104, and / or (iii) VL CDR1, CDR2 and CDR3, wherein the VL CDR1 is selected from SEQ ID NOs: 2126 to 2130, the VL CDR2 is selected from SEQ ID NOs: 2152 to 2156, and the VL CDR3 is selected from SEQ ID NOs: 2178 to 2182.

[0031] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, wherein VH CDR3 comprises the amino acid sequence ARDGPX1X2X3DYYMDV (sequence number 2204), wherein X1 is R or Q, X2 is V, D, L or E, and X3 is S or V. In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises VH CDR1, CDR2 and CDR3, wherein (i) VH CDR1 comprises the amino acid sequence YTFX1X2YX3MH (sequence number 2202), where X1 is T or H, X2 is S, G or H, and X3 is Y or P; and / or (ii) VH CDR2 comprises the amino acid sequence X4INPSX5GX6TX7YAQKFQG (sequence number 2203), where X4 is I or S, X5 is G or R, X6 is S or R, and X7 is S or E.

[0032] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, wherein VL CDR3 comprises the amino acid sequence QQRDNWPFT (SEQ ID NO: 2116). In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises VL CDR1, CDR2, and CDR3, wherein (i) VL CDR1 comprises the amino acid sequence RASQSVSSYLA (SEQ ID NO: 2116); and / or (ii) VL CDR2 comprises the amino acid sequence DASNRAT (SEQ ID NO: 2116).

[0033] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises (i) a VH CDR1, CDR2, and CDR3, wherein the VH CDR1 is selected from SEQ ID NOs: 2053-2057, the VH CDR2 is selected from SEQ ID NOs: 2079-2083, and the VH CDR3 is selected from SEQ ID NOs: 2105-2109, and / or (ii) a VL CDR1, CDR2, and CDR3, wherein the VL CDR1 is selected from SEQ ID NOs: 2131-2135, the VL CDR2 is selected from SEQ ID NOs: 2157-2161, and the VL CDR3 is selected from SEQ ID NOs: 2183-2187.

[0034] In some embodiments, an anti-FIXa antibody, or antigen-binding portion thereof, disclosed herein that specifically binds to FIXa comprises a VH CDR1, CDR2, and CDR3, and a VL CDR1, CDR2, and CDR3, wherein the VH CDR3 comprises the amino acid sequence ARDKYQDYSX1DI (SEQ ID NO: 2207), and X1 is F or V. In some embodiments, an anti-FIXa antibody, or antigen-binding portion thereof, disclosed herein that specifically binds to FIXa comprises a VH CDR1, CDR2, and CDR3, wherein (i) the VL CDR1 comprises the amino acid sequence GSIX1SX2X3YX4WX5 (SEQ ID NO: 2205), and X1 is S or A, X2 is S, T, G, or V, X3 is S or A, X4 is Y or A, and X5 is G, V, N, or S; and / or (ii) the VH CDR2 comprises the amino acid sequence X6IX7X8X9GX 10 TX 11 YNPSLK X6 is S or Y, X7 is S, Y, R, T or Q, X8 is Y, G, P or A, X9 is S or Q, and X 10 is S or X 11 is Y or Q.

[0035] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises a VL CDR1, CDR2, and CDR3, wherein the VL CDR3 comprises the amino acid sequence QQANFLPFT (SEQ ID NO: 2188). In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises a VL CDR1, CDR2, and CDR3, wherein (i) the VL CDR1 comprises the amino acid sequence RASQGIDSWLA (SEQ ID NO: 2136); and / or (ii) the VL CDR2 comprises the amino acid sequence AASSLQS (SEQ ID NO: 2162).

[0036] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises (i) a VH CDR1, CDR2, and CDR3, wherein the VH CDR1 is selected from SEQ ID NOs: 2058-2063, the VH CDR2 is selected from SEQ ID NOs: 2084-2089, and the VH CDR3 is selected from SEQ ID NOs: 2110-2115, and / or (ii) a VL CDR1, CDR2, and CDR3, wherein the VL CDR1 is selected from SEQ ID NOs: 2136-2141, the VL CDR2 is selected from SEQ ID NOs: 2162-2167, and the VL CDR3 is selected from SEQ ID NOs: 2188-2193.

[0037] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises a VH and a VL, wherein (i) the VH has at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, or at least about 100% identity with an amino acid sequence selected from the group consisting of SEQ ID NOs: 1935, 1939, 1943, 1947, 1951, 1955, 1959, 1963, 1967, 1971, 1975, 1979, 1983, 1987, 1991, 1995, 1999, 2003, 2007, 2011, 2015, 2019, 2023, 2027, 2031, and 2035; and / or (ii) the VL comprises an amino acid sequence at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99% or about 100% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 1937, 1941, 1945, 1949, 1953, 1957, 1961, 1965, 1969, 1973, 1977, 1981, 1985, 1989, 1993, 1997, 2001, 2005, 2009, 2013, 2017, 2021, 2025, 2029, 2033 and 2037.

[0038] In some aspects, an anti-FIXa antibody or antigen-binding portion thereof disclosed herein that specifically binds to FIXa comprises a VH and a VL, wherein (a1) the VH and VL comprise SEQ ID NOs: 1935 and 1937 (BIIB-9-3595), respectively; (a2) the VH and VL comprise SEQ ID NOs: 1939 and 1941 (BIIB-9-3601), respectively; (a3) ​​the VH and VL comprise SEQ ID NOs: 1943 and 1945 (BIIB-9-3604), respectively; and (a4) the VH and VL comprise SEQ ID NO: 1947. and 1949 (BIIB-9-3617); (a5) VH and VL comprise SEQ ID NOs: 1951 and 1953 (BIIB-9-3618); (a6) VH and VL comprise SEQ ID NOs: 1955 and 1957 (BIIB-9-3621); (a7) VH and VL comprise SEQ ID NOs: 1959 and 1961 (BIIB-9-3647); (a8) VH and VL comprise SEQ ID NOs: 1963 and 1965 (BIIB-9-3649); (a9) VH and VL comprise SEQ ID NOs: (a10) VH and VL comprise SEQ ID NOs: 1967 and 1969 (BIIB-9-3650); (a11) VH and VL comprise SEQ ID NOs: 1971 and 1973 (BIIB-9-3654), respectively; (a12) VH and VL comprise SEQ ID NOs: 1979 and 1981 (BIIB-9-3754), respectively; (a13) VH and VL comprise SEQ ID NOs: 1983 and 1985 (BIIB-9-3755), respectively. -9-3756); (a14) VH and VL comprise SEQ ID NOs: 1987 and 1989, respectively (BIIB-9-3764); (a15) VH and VL comprise SEQ ID NOs: 1991 and 1993, respectively (BIIB-9-3766); (a16) VH and VL comprise SEQ ID NOs: 1995 and 1997, respectively (BIIB-9-3707); (a17) VH and VL comprise SEQ ID NOs: 1999 and 2001, respectively (BIIB-9-3709); (a18) VH and (a19) VH and VL comprise SEQ ID NOs: 2007 and 2009 (BIIB-9-3727), respectively; (a20) VH and VL comprise SEQ ID NOs: 2011 and 2013 (BIIB-9-3745), respectively; (a21) VH and VL comprise SEQ ID NOs: 2015 and 2017 (BIIB-9-3780), respectively; (a22) VH and VL comprise SEQ ID NOs: 2019 and 2020, respectively. 21 (BIIB-9-3675); (a23) the VH and VL comprise SEQ ID NOs: 2023 and 2025, respectively (BIIB-9-3681); (a24) the VH and VL comprise SEQ ID NOs: 2027 and 2029, respectively (BIIB-9-3684); (a25) the VH and VL comprise SEQ ID NOs: 2031 and 2033, respectively (BIIB-9-3698); or (a26) the VH and VL comprise SEQ ID NOs: 2035 and 2037, respectively (BIIB-9-3704).

[0039] Embodiment Embodiment 1. An isolated antibody or antigen-binding portion thereof ("anti-FIXa antibody or antigen-binding portion thereof") that specifically binds to activated factor IX (FIXa), wherein the anti-FIXa antibody or antigen-binding portion thereof preferentially binds to FIXa in the presence of FIXa and factor IX zymogen (FIXz).

[0040] Embodiment 2. The anti-FIXa antibody, or antigen-binding portion thereof, of embodiment 1, which binds to FIXa with a higher binding affinity than the binding affinity of the anti-FIXa antibody, or antigen-binding portion thereof, to FIXz.

[0041] Embodiment 3. An isolated anti-FIXa antibody, or antigen-binding portion thereof, that binds to FIXa with a binding affinity that is greater than the binding affinity of the anti-FIXa antibody, or antigen-binding portion thereof, to FIXz.

[0042] Embodiment 4. A K of about 100 nM or less, about 90 nM or less, about 80 nM or less, about 70 nM or less, about 60 nM or less, about 50 nM or less, about 40 nM or less, about 30 nM or less, about 20 nM or less, about 10 nM or less, or about 1 nM or less as determined by a Biolayer Interferometry (BLI) assay. D The anti-FIXa antibody or antigen-binding portion thereof of any preceding embodiment, which binds to FIXa.

[0043] Embodiment 5. The anti-FIXa antibody or antigen-binding portion thereof of any of the preceding embodiments, wherein the FIXa is free FIXa, FIXa in the tenase complex, or FIXa covalently linked to EGR-CMK (FIXa-SM).

[0044] Embodiment 6 The anti-FIXa antibody or antigen-binding portion thereof of any preceding embodiment, wherein FIXz comprises inactivatable factor IX (FIXn).

[0045] Embodiment 7. The anti-FIXa antibody, or antigen-binding portion thereof, of any of the preceding embodiments, which cross-competes with a reference antibody selected from the group consisting of the antibodies in Figures 3A, 3B, and 3C.

[0046] Embodiment 8. The anti-FIXa antibody, or antigen-binding portion thereof, of any of the preceding embodiments, which binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figures 3A, 3B, and 3C.

[0047] Embodiment 9. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 7 or 8, wherein the reference antibody is selected from BIIB-9-484, BIIB-9-440, BIIB-9-882, BIIB-9-460, BIIB-9-433, and any combination thereof.

[0048] Embodiment 10. The anti-FIXa antibody, or antigen-binding portion thereof, of any of the preceding embodiments, which binds preferentially to FIXa-SM compared to free FIXa or FIXz and / or binds to FIXa-SM with a binding affinity that is greater than the binding affinity of the anti-FIXa antibody, or antigen-binding portion thereof, for free FIXa or FIXz.

[0049] Embodiment 11. The anti-FIXa antibody, or antigen-binding portion thereof, of any of the preceding embodiments, which cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 3A.

[0050] Embodiment 12. The anti-FIXa antibody, or antigen-binding portion thereof, of any of the preceding embodiments, which binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figure 3A.

[0051] Embodiment 13. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 11 or 12, wherein the reference antibody is selected from BIIB-9-484, BIIB-9-440, BIIB-9-460, and any combination thereof.

[0052] Embodiment 14. The anti-FIXa antibody, or antigen-binding portion thereof, of any preceding embodiment, which binds preferentially to free FIXa compared to FIXa-SM or FIXz and / or binds to free FIXa with a binding affinity that is greater than the binding affinity of the anti-FIXa antibody, or antigen-binding portion thereof, for FIXa-SM or FIXz.

[0053] Embodiment 15. The anti-FIXa antibody, or antigen-binding portion thereof, of any preceding embodiment, which cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 3B.

[0054] Embodiment 16. The anti-FIXa antibody, or antigen-binding portion thereof, of any of the preceding embodiments, which binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figure 3B.

[0055] Embodiment 17. The anti-FIXa antibody, or antigen-binding portion thereof, of any preceding embodiment, which binds preferentially to free FIXa or FIXa-SM compared to FIXz and / or binds to free FIXa or FIXa-SM with a binding affinity that is greater than the binding affinity of the anti-FIXa antibody, or antigen-binding portion thereof, for FIXz.

[0056] Embodiment 18. The anti-FIXa antibody, or antigen-binding portion thereof, of any preceding embodiment, which cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 3C.

[0057] Embodiment 19. The anti-FIXa antibody, or antigen-binding portion thereof, of any preceding embodiment, which binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figure 3C.

[0058] Embodiment 20. The reference antibody is BIIB-9-882, BIIB-9-433 and the like. 20. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 18 or 19, selected from any combination thereof:

[0059] Embodiment 21. The anti-FIXa antibody or antigen-binding portion thereof of any of the preceding embodiments, comprising CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VH CDR3 selected from the group consisting of the VH CDR3 in Figure 3A, Figure 3B and Figure 3C or a VH CDR3 having one or two mutations.

[0060] Embodiment 22. An anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 1 to 21, comprising CDR1, CDR2 and CDR3, wherein CDR3 comprises ARDX1X2X3X4X5X6YYX7MDV (sequence number 753), wherein X1 is V or G, X2 is G or V, X3 is G or R, X4 is Y or V, X5 is A or S, X6 is G or D, and X7 is G or absent.

[0061] Embodiment 23. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 22, wherein CDR3 comprises ARDVGGYAGYYGMDV (SEQ ID NO: 905, BIIB-9-484, 1335, 1336), ARDISTDGESSLYYYMDV (SEQ ID NO: 901, BIIB-9-460), ARGPTDSSGYLDMDV (SEQ ID NO: 1186, BIIB-9-882), or ARDGPRVSDYY MDV (SEQ ID NO: 912, BIIB-9-619).

[0062] Embodiment 24. The anti-FIXa antibody or antigen-binding portion thereof of any of the preceding embodiments, comprising CDR1, CDR2 and CDR3, wherein CDR1 comprises a VH CDR1 selected from the group consisting of the VH CDR1 in Figure 3A, Figure 3B and Figure 3C or a VH CDR1 having one or two mutations.

[0063] Embodiment 25. A VH CDR1, CDR2 and CDR3, wherein CDR2 is a VH CDR2 in Figure 3A, Figure 3B and Figure 3C, or a VH CDR2 with one or two mutations. The anti-FIXa antibody or antigen-binding portion thereof of any preceding embodiment, comprising a VH CDR2 selected from the group consisting of:

[0064] Embodiment 26. A VL CDR1, CDR2 and CDR3, wherein CDR1 is a VL CDR1 in Figure 3A, Figure 3B and Figure 3C or a VL CDR1 with one or two mutations. The anti-FIXa antibody or antigen-binding portion thereof of any preceding embodiment, comprising a VL CDR1 selected from the group consisting of:

[0065] Embodiment 27. A VL CDR1, CDR2 and CDR3, wherein CDR2 is a VL CDR2 in Figure 3A, Figure 3B and Figure 3C or a VL CDR2 with one or two mutations. The anti-FIXa antibody or antigen-binding portion thereof of any preceding embodiment, comprising a VL CDR2 selected from the group consisting of:

[0066] Embodiment 28. A VL CDR1, CDR2 and CDR3, wherein CDR3 is a VL CDR3 in Figure 3A, Figure 3B and Figure 3C or a VL CDR3 with one or two mutations. The anti-FIXa antibody or antigen-binding portion thereof of any preceding embodiment, comprising a VL CDR3 selected from the group consisting of:

[0067] Embodiment 29. An isolated anti-FIXa antibody or antigen-binding portion thereof that specifically binds to FIXa, comprising VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, and the VL CDR1, CDR2 and CDR3 comprise the VH CDR1, VH CDR2 and VH CDR3, and the VL CDR1, CDR2 and CDR3 of Figures 3A, 3B and 3C, respectively.

[0068] Embodiment 30. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 29, comprising VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NOs: 815, 860 and 905, respectively, and / or VL CDR1, CDR2 and CDR3 sequences comprising SEQ ID NOs: 950, 995 and 1040, respectively (BIIB-9-484).

[0069] Embodiment 31. (a1) The antibody comprises VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NO: 809, SEQ ID NO: 854, and SEQ ID NO: 899, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 944, SEQ ID NO: 989, and SEQ ID NO: 1034, respectively (BIIB-9-440); (a2) the antibody comprises VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NO: 1102, SEQ ID NO: 1144, and SEQ ID NO: 1186, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 1228, SEQ ID NO: 1270, and SEQ ID NO: 1312, respectively (BIIB-9-882); (a3) the antibody comprises VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NO: 811, SEQ ID NO: 856, and SEQ ID NO: 901, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 946, SEQ ID NO: 991, and SEQ ID NO: 1036, respectively (BIIB-9-460); or (a4) An anti-FIXa antibody or antigen-binding portion thereof of embodiment 29, wherein the antibody comprises VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO: 1108, SEQ ID NO: 1150 and SEQ ID NO: 1192, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 1234, SEQ ID NO: 1276 and SEQ ID NO: 1318, respectively (BIIB-9-433).

[0070] Embodiment 32. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 29, wherein the antibody comprises VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO: 822, SEQ ID NO: 867 and SEQ ID NO: 912, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 957, SEQ ID NO: 1002 and SEQ ID NO: 1047, respectively (BIIB-9-619).

[0071] Embodiment 33. An anti-FIXa antibody or antigen-binding portion thereof of embodiment 29, wherein (i) the antibody comprises VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO: 843, SEQ ID NO: 888 and SEQ ID NO: 933, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 950, SEQ ID NO: 995 and SEQ ID NO: 1040, respectively, or (ii) the antibody comprises VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO: 844, SEQ ID NO: 889 and SEQ ID NO: 934, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 950, SEQ ID NO: 995 and SEQ ID NO: 1040, respectively (BIIB-9-1335 and BIIB-9-1336).

[0072] Embodiment 34. A VH and a VL, wherein VH is selected from the group consisting of SEQ ID NOs: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 138, 139, 145, 146, 1 1, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149, 151, 153 , 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, and 181, comprising an amino acid sequence that is at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99% or about 100% identical to an amino acid sequence selected from the group consisting of:

[0073] Embodiment 35. A VH and a VL, wherein VL is selected from the group consisting of SEQ ID NOs: 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 246, 247, 248, 249, 250, 251, 252, 253, 254, 255, 256, 257, 258, 259, 260, 261, 262, 263, 264, 265, 266, 267, 268, 269, 270, 271, 272, 273, 274, 275, 276, 277, 278, 279, 280, 281, 282, 283, 284, 285, 286, 287, 288, 289, 290, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 3 47, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 295, 297, 299, 301, 303, 305, 307, 309, 311, 3 359, 361, 363, 365, and 367. The anti-FIXa antibody or antigen-binding portion thereof of any preceding embodiment, comprising an amino acid sequence at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99% or about 100% identical to an amino acid sequence selected from the group consisting of: 13, 315, 317, 319, 321, 323, 325, 327, 329, 331, 333, 335, 337, 339, 341, 343, 345, 347, 349, 351, 353, 355, 357, 359, 361, 363, 365, and 367.

[0074] Embodiment 36. An anti-FIXa antibody or antigen-binding portion thereof of any of the preceding embodiments, comprising a VH and a VL, wherein the VH is derived from the germline sequence of VH1-46.0, VH1-46.4, VH1-46.5, VH1-46.7, VH1-46.9, VH1-69.9, VH3-07.0, VH3-21.0, VH3-21.2, VH3-23.0, VH3-23.1, VH4-31.0, VH4-34.0, VH4-39.0, VH4-39.2, VH4-39.3, VH4-39.5, VH4-39.6, VH4-39.8, VH4-59.6, VH4-0B.4, or VH4-0B.6.

[0075] Embodiment 37. VH and VL, wherein VL is selected from the group consisting of VK1-05.0, VK1-05.6, VK1-05.9, VK1-05.21, VK1-12.0, VK1-12.3, VK1-33.0, VK1-33.1, VK1-33.2, VK1-33.8, VK1-33.10, VK1-39.0, VK1-39.6, VK2-28.0, VK2-28.1, VK3-11.0, VK3-11.2, VK3- 11.6, VK3-11.10, VK3-11.14, VK3-15.0, VK3-15.6, VK3-15.8, VK3-15.11, VK3-15.20, VK3-15.26, VK3-20.0, VK3-20.4, VK3-20.5, VK3-20.8, or VK4-01.0 germline sequence.

[0076] Embodiment 38. Comprising VH and VL, (a1) VH and VL comprise SEQ ID NOs: 31 and 221 (BIIB-9-484), respectively; (a2) VH and VL comprise SEQ ID NOs: 19 and 209 (BIIB-9-440), respectively; (a3) VH and VL comprise SEQ ID NOs: 115 and 301 (BIIB-9-882), respectively; (a4) VH and VL comprise SEQ ID NOs: 23 and 213 (BIIB-9-460), respectively; (a5) VH and VL are SEQ ID NOs: 127 and 313 (BIIB-9-4 33); (a6) VH and VL comprise SEQ ID NOs: 45 and 235 (BIIB-9-619), respectively; (a7) VH and VL comprise SEQ ID NOs: 185 and 371 (BIIB-9-578), respectively; (a8) VH and VL comprise SEQ ID NOs: 87 and 221 (BIIB-9-1335), respectively; or (a9) VH and VL comprise SEQ ID NOs: 89 and 221 (BIIB-9-1336), respectively The anti-FIXa antibody or antigen-binding portion thereof of any of the preceding embodiments.

[0077] Embodiment 39. An isolated antibody or antigen-binding portion thereof ("anti-FIXz antibody or antigen-binding portion thereof") that specifically binds to FIXz, wherein the anti-FIXz antibody or antigen-binding portion thereof preferentially binds to FIXz in the presence of free FIXa or FIXa-SM and / or the anti-FIXz antibody or antigen-binding portion thereof binds to FIXz with a higher binding affinity than the binding affinity of the anti-FIXz antibody or antigen-binding portion thereof to free FIXa or FIXa-SM.

[0078] Embodiment 40 The anti-FIXz antibody, or antigen-binding portion thereof, of any preceding embodiment, which cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 3D.

[0079] Embodiment 41 The anti-FIXz antibody, or antigen-binding portion thereof, of any preceding embodiment, which binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figure 3D.

[0080] Embodiment 42 The anti-FIXz antibody or antigen-binding portion thereof of embodiment 40 or 41, wherein the reference antibody is BIIB-9-578.

[0081] Embodiment 43. The anti-FIXz antibody or antigen-binding portion thereof of any preceding embodiment, comprising CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VH CDR3 selected from the group consisting of the VH CDR3 in Figure 3D or a VH CDR3 having one or two mutations.

[0082] Embodiment 44 The anti-FIXz antibody or antigen-binding portion thereof of embodiment 43, wherein CDR3 comprises ARDKYQDYSFDI (SEQ ID NO: 1355, BIIB-9-578).

[0083] Embodiment 45. The anti-FIXz antibody or antigen-binding portion thereof of any preceding embodiment, comprising CDR1, CDR2 and CDR3, wherein CDR1 comprises a VH CDR1 selected from the group consisting of the VH CDR1 in Figure 3D or a VH CDR1 having one or two mutations.

[0084] Embodiment 46 The anti-FIXz antibody or antigen-binding portion thereof of any preceding embodiment, comprising a VH CDR1, CDR2 and CDR3, wherein CDR2 comprises a VH CDR2 selected from the group consisting of the VH CDR2 in Figure 3D or a VH CDR2 having one or two mutations.

[0085] Embodiment 47. The anti-FIXz antibody or antigen-binding portion thereof of any preceding embodiment, comprising a VL CDR1, CDR2 and CDR3, wherein CDR1 comprises a VL CDR1 selected from the group consisting of the VL CDR1 in Figure 3D or a VL CDR1 having one or two mutations.

[0086] Embodiment 48 The anti-FIXz antibody or antigen-binding portion thereof of any preceding embodiment, comprising a VL CDR1, CDR2 and CDR3, wherein CDR2 comprises a VL CDR2 selected from the group consisting of the VL CDR2 in Figure 3D or a VL CDR2 having one or two mutations.

[0087] Embodiment 49. The anti-FIXz antibody or antigen-binding portion thereof of any preceding embodiment, comprising a VL CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VL CDR3 selected from the group consisting of the VL CDR3 in Figure 3D or a VL CDR3 having one or two mutations.

[0088] Embodiment 50 The anti-FIX antibody or antigen-binding portion thereof of any one of the preceding embodiments and embodiments 169 to 204, wherein the antibody is selected from the group consisting of IgG1, IgG2, IgG3, IgG4 or a variant thereof.

[0089] Embodiment 51 The anti-FIX antibody or antigen-binding portion thereof of embodiment 50, wherein the antibody is an IgG4 antibody.

[0090] Embodiment 52 The anti-FIX antibody or antigen-binding portion thereof of embodiment 50, wherein the antibody comprises an effector-less IgG4 Fc.

[0091] Embodiment 53 The anti-FIX antibody or antigen-binding portion thereof of any one of the preceding embodiments and embodiments 169 to 204, comprising a heavy chain constant region.

[0092] Embodiment 54 The anti-FIX antibody of any one of the preceding embodiments and embodiments 169 to 204, wherein the antibody is a human antibody, an engineered antibody, or a humanized antibody.

[0093] Embodiment 55. The anti-FIX antigen-binding portion of any one of the preceding embodiments and embodiments 169 to 204, wherein the antigen-binding portion comprises a Fab, a Fab', a F(ab')2, an Fv, or a single-chain Fv (scFv).

[0094] Embodiment 56. A bispecific molecule comprising the anti-FIX antibody, or antigen-binding portion thereof, of any one of the preceding embodiments and embodiments 169 to 204, linked to a molecule with a second binding specificity.

[0095] Embodiment 57. A nucleic acid encoding the heavy and / or light chain variable region of the anti-FIX antibody, or antigen-binding portion thereof, of any one of embodiments 1 to 55 and embodiments 169 to 204, or the bispecific molecule of embodiment 56.

[0096] Embodiment 58. An expression vector comprising the nucleic acid molecule of embodiment 57.

[0097] Embodiment 59. A cell transformed with the expression vector of embodiment 58.

[0098] Embodiment 60. An immunoconjugate comprising an antibody or antigen-binding portion thereof according to any one of embodiments 1 to 55 and embodiments 169 to 204, or a bispecific molecule of embodiment 56, wherein the immunoconjugate is linked to an agent.

[0099] Embodiment 61. A composition comprising the antibody or antigen-binding portion thereof of any one of embodiments 1 to 55 and embodiments 169 to 204, the bispecific molecule of embodiment 56, or the immunoconjugate of embodiment 60, and a carrier.

[0100] Embodiment 62. A kit comprising the antibody or antigen-binding portion thereof of any one of embodiments 1 to 55 and embodiments 169 to 204, the bispecific molecule of embodiment 56, or the immunoconjugate of embodiment 60, and instructions for use.

[0101] Embodiment 63. A method of producing an anti-FIX antibody or antigen-binding portion thereof, comprising expressing the antibody or antigen-binding portion thereof in a cell of embodiment 59, and isolating the antibody or antigen-binding portion thereof from the cell.

[0102] Embodiment 64. A method for measuring the level of activated FIX in a subject in need thereof, comprising contacting an anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 1 to 55 and embodiments 169 to 204 with a sample obtained from the subject under suitable conditions, and measuring binding of the anti-FIXa antibody or antigen-binding portion thereof to FIXa in the sample.

[0103] Embodiment 65 The method of embodiment 64, wherein the sample is blood or serum.

[0104] Embodiment 66. An isolated antibody or antigen-binding portion thereof ("anti-FXz antibody or antigen-binding portion thereof") that specifically binds to factor X zymogen (FXz), wherein the anti-FXz antibody or antigen-binding portion thereof preferentially binds to FXz in the presence of FXz and activated factor X (FXa).

[0105] Embodiment 67 The anti-FXz antibody, or antigen-binding portion thereof, of embodiment 66, which binds to FXz with a binding affinity that is higher than the binding affinity of the antibody, or antigen-binding portion thereof, to FXa.

[0106] Embodiment 68. An isolated anti-FXz antibody, or antigen-binding portion thereof, that binds to FXz with a binding affinity that is higher than the binding affinity of the antibody, or antigen-binding portion thereof, to FXa.

[0107] Embodiment 69. A K of about 100 nM or less, about 90 nM or less, about 80 nM or less, about 70 nM or less, about 60 nM or less, about 50 nM or less, about 40 nM or less, about 30 nM or less, about 20 nM or less, about 10 nM or less, or about 1 nM or less as measured by BLI. D 69. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 68, which binds to FXz at

[0108] Embodiment 70 The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 69, wherein the FXa is free FXa or FXa covalently linked to EGR-CMK (FIXa-SM).

[0109] Embodiment 71 The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 70, wherein FXz comprises inactivatable factor X (FXn).

[0110] Embodiment 72 The anti-FXz antibody, or antigen-binding portion thereof, of any one of embodiments 66 to 71, which cross-competes with a reference antibody selected from the group consisting of the antibodies in Figures 12A and 12B.

[0111] Embodiment 73 The anti-FXz antibody, or antigen-binding portion thereof, of any one of embodiments 66 to 72, which binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figures 12A and 12B.

[0112] Embodiment 74 The anti-FXz antibody or antigen-binding portion thereof of embodiment 73, which binds to the same epitope as a reference antibody selected from the group consisting of BIIB-12-915, BIIB-12-917, BIIB-12-932, and any combination thereof.

[0113] Embodiment 75. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 74, comprising CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VH CDR3 selected from the group consisting of the VH CDR3 in Figure 12A and Figure 12B or a VH CDR3 having one or two mutations.

[0114] Embodiment 76. An anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 75, comprising CDR1, CDR2 and CDR3, wherein CDR3 comprises ARX1X2X3RX4X5X6X7FDX8 (sequence number 766), wherein X1 is G or L, X2 is R or G, X3 is F or Y, X4 is P or G, X5 is R or A, X6 is G or S, X7 is R or A, and X8 is Y or I.

[0115] Embodiment 77. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 76, comprising CDR1, CDR2 and CDR3, wherein CDR3 comprises ARGRFRPRGRFDY (SEQ ID NO: 1575, BIIB-12-917), ARLGYRGASAFDI (SEQ ID NO: 1589, BIIB-12-932) or ARVGGGYANP (SEQ ID NO: 1573, BIIB-12-915).

[0116] Embodiment 78. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 77, comprising a VH CDR1, CDR2 and CDR3, wherein CDR1 comprises a VH CDR1 selected from the group consisting of the VH CDR1 in Figure 12A and Figure 12B or a VH CDR1 having one or two mutations.

[0117] Embodiment 79. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 78, comprising a VH CDR1, CDR2 and CDR3, wherein CDR2 comprises a VH CDR2 selected from the group consisting of the VH CDR2 in Figure 12A and Figure 12B or a VH CDR2 having one or two mutations.

[0118] Embodiment 80. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 79, comprising a VL CDR1, CDR2 and CDR3, wherein CDR1 comprises a VL CDR1 selected from the group consisting of the VL CDR1 in Figure 12A and Figure 12B or a VL CDR1 having one or two mutations.

[0119] Embodiment 81. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 80, comprising a VL CDR1, CDR2 and CDR3, wherein CDR2 comprises a VL CDR2 selected from the group consisting of the VL CDR2 in Figure 12A and Figure 12B or a VL CDR2 having one or two mutations.

[0120] Embodiment 82. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 81, comprising a VL CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VL CDR3 selected from the group consisting of the VL CDR3 in Figure 12A and Figure 12B or a VL CDR3 having one or two mutations.

[0121] Embodiment 83. An isolated antibody or antigen-binding portion thereof that specifically binds to FXz, comprising VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, wherein the VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, comprise the VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3 of Figures 12A and 12B, respectively.

[0122] Embodiment 84. The anti-FXz antibody or antigen-binding portion thereof of embodiment 83, wherein the antibody comprises VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO: 1393, 1483 or 1573, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 1663, 1753 and 1843, respectively (BIIB-12-915).

[0123] Embodiment 85. The anti-FXz antibody or antigen-binding portion thereof of embodiment 83, wherein the antibody comprises VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO: 1395, 1485 or 1575, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 1665, 1755 and 1845, respectively (BIIB-12-917).

[0124] Embodiment 86. The anti-FXz antibody or antigen-binding portion thereof of embodiment 83, wherein the antibody comprises VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO: 1409, 1499 or 1589, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 1679, 1769 and 1859, respectively (BIIB-12-932).

[0125] Embodiment 87. A VH and a VL, wherein VH is selected from the group consisting of SEQ ID NOs: 377, 379, 381, 383, 385, 387, 389, 391, 393, 395, 397, 399, 401, 403, 405, 407, 409, 411, 413, 415, 417, 419, 421, 423, 425, 427, 429, 431, 433 , 435, 437, 439, 441, 443, 445, 447, 449, 451, 453, 455, 457, 459, 461, 463, 465, 467, 469, 471, 473, 475, 477, 479, 481, 483, 485, 487, 489, 491, 493, 495, 497, 499, 5 87. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 86, comprising an amino acid sequence at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99% or about 100% identical to an amino acid sequence selected from the group consisting of: 501, 503, 505, 507, 509, 511, 513, 515, 517, 519, 521, 523, 525, 527, 529, 531, 533, 535, 537, 539, 541, 543, 545, 547, 549, 551, 553, and 555.

[0126] Embodiment 88. A VH and a VL, wherein VL is selected from the group consisting of SEQ ID NOs: 565, 567, 569, 571, 573, 575, 579, 581, 583, 585, 587, 589, 591, 593, 595, 597, 599, 601, 603, 605, 607, 609, 611, 613, 615, 617, 619, 621, 622, 623, 624, 625, 626, 627, 628, 629, 630, 631, 632, 633, 634, 635, 636, 637, 638, 639, 640, 641, 642, 643, 644, 645, 646, 647, 648, 649, 650, 651, 652, 653, 654, 655, 656, 657, 658, 659, 660, 661, 662, 663, 664, 665, 666, 667, 668, 669, 670, 671, 672, 673, 674, 675, 676, 677, 678, 679, 680, 681, 682, 683, 684, 685, 686, 687, 688, 689, 6 3, 625, 627, 629, 631, 633, 635, 637, 639, 641, 643, 645, 647, 649, 651, 653, 655, 657, 659, 661, 663, 665, 667, 669, 671, 673, 675, 677, 679, 681, 683, 685, 687, 689, 88. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 87, comprising an amino acid sequence at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99% or about 100% identical to an amino acid sequence selected from the group consisting of: 691, 693, 695, 697, 699, 701, 703, 705, 707, 709, 711, 713, 715, 717, 719, 721, 723, 725, 727, 729, 731, 733, 735, 737, 739, 741, and 743.

[0127] Embodiment 89. The antibody comprises a VH and a VL, wherein VH is selected from the group consisting of VH1-18.0, VH1-18. 89. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 88, wherein the antibody or antigen-binding portion is derived from the germline sequence of VH1-18.8, VH1-46.0, VH1-46.4, VH1-46.5, VH1-46.6, VH1-46.7, VH1-46.8, VH1-46.9, VH3-21.0, VH3-23.0, VH3-23.2, VH3-23.6, VH3-30.0, VH4-31.5, VH4-39.0, VH4-39.5, VH4-0B.4 or VH5-51.1.

[0128] Embodiment 90. The antibody comprises a VH and a VL, wherein the VL is selected from the group consisting of VK1-05.6, VK1-05.12, VK1-12.0, VK1-12.4, VK1-12.7, VK1-12.10, VK1-12.15, VK1-39.0, VK1-39.3, VK1-39.15, VK2-28.0, VK2-28.1, VK2-28.5, VK3-11.0, VK3-11.2, VK3- 90. The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 89, wherein the antibody or antigen-binding portion is derived from the germline sequence of VK3-11.6, VK3-11.14, VK3-15.0, VK3-15.8, VK3-15.10, VK3-20.0, VK3-20.1, VK3-20.4, VK3-20.5, VK4-01.0, VK4-01.4, VK4-01.20.

[0129] Embodiment 91. Comprising VH and VL, (b1) VH and VL comprise SEQ ID NOs: 423 and 611 (BIIB-12-915), respectively; (b2) VH and VL comprise SEQ ID NOs: 427 and 615 (BIIB-12-917), respectively; or (b3) The anti-FXz antibody or antigen-binding portion thereof of any one of embodiments 66 to 90, wherein the VH and VL comprise SEQ ID NOs: 455 and 643 (BIIB-12-932), respectively.

[0130] Embodiment 92. An isolated antibody or antigen-binding portion thereof that specifically binds to activated factor X (FXa) ("anti-FXa antibody or antigen-binding portion thereof"), wherein the anti-FXa antibody or antigen-binding portion thereof preferentially binds to FXa in the presence of FXz and FXa and / or binds to FXa with a binding affinity that is higher than the binding affinity of the antibody or antigen-binding portion thereof to FXz.

[0131] Embodiment 93 The anti-FXa antibody, or antigen-binding portion thereof, of embodiment 92, which cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 12C.

[0132] Embodiment 94 The anti-FXa antibody or antigen-binding portion thereof of embodiment 92 or 93, which binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figure 12C.

[0133] Embodiment 95 The anti-FXa antibody, or antigen-binding portion thereof, of embodiment 94, which binds to the same epitope as a reference antibody selected from the group consisting of BIIB-12-925.

[0134] Embodiment 96. The anti-FXa antibody or antigen-binding portion thereof of any one of embodiments 92 to 95, comprising CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VH CDR3 selected from the group consisting of the VH CDR3 in Figure 12C or a VH CDR3 having one or two mutations.

[0135] Embodiment 97 The anti-FXa antibody or antigen-binding portion thereof of any one of embodiments 92 to 96, comprising CDR1, CDR2 and CDR3, wherein CDR3 comprises AKGPRYYWYSWYFDL (SEQ ID NO: 1919, BIIB-12-925).

[0136] Embodiment 98. The anti-FXa antibody or antigen-binding portion thereof of any one of embodiments 92 to 97, comprising a VH CDR1, CDR2 and CDR3, wherein CDR1 comprises a VH CDR1 selected from the group consisting of the VH CDR1 in Figure 12C or a VH CDR1 having one or two mutations.

[0137] Embodiment 99. The anti-FXa antibody or antigen-binding portion thereof of any one of embodiments 92 to 98, comprising a VH CDR1, CDR2 and CDR3, wherein CDR2 comprises a VH CDR2 selected from the group consisting of the VH CDR2 in Figure 12C or a VH CDR2 having one or two mutations.

[0138] Embodiment 100. The anti-FXa antibody or antigen-binding portion thereof of any one of embodiments 92 to 99, comprising a VL CDR1, CDR2 and CDR3, wherein CDR1 comprises a VL CDR1 selected from the group consisting of the VL CDR1 in Figure 12C or a VL CDR1 having one or two mutations.

[0139] Embodiment 101. The anti-FXa antibody or antigen-binding portion thereof of any one of embodiments 92 to 100, comprising a VL CDR1, CDR2 and CDR3, wherein CDR2 comprises a VL CDR2 selected from the group consisting of the VL CDR2 in Figure 12C or a VL CDR2 having one or two mutations.

[0140] Embodiment 102. The anti-FXa antibody or antigen-binding portion thereof of any one of embodiments 92 to 101, comprising a VL CDR1, CDR2 and CDR3, wherein the CDR3 comprises a VL CDR3 selected from the group consisting of the VL CDR3 in Figure 12C or a VL CDR3 having one or two mutations.

[0141] Embodiment 103. An isolated antibody or antigen-binding portion thereof that specifically binds to FXa, comprising VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, wherein the VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, respectively, comprise the VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3 of Figure 12C.

[0142] Embodiment 104. An antibody comprising VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NO: 1911, 1915, or 1919, respectively, and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 1923, 1927, or 1931, respectively. 104. The anti-FXa or antigen-binding portion thereof of embodiment 103, comprising the CDR3 sequence (BIIB-12-925).

[0143] Embodiment 105. The anti-FXa antibody or antigen-binding portion thereof of any one of embodiments 92 to 104, comprising a VH and a VL, wherein the VH and VL comprise SEQ ID NOs: 559 and 747 (BIIB-12-925), respectively.

[0144] Embodiment 106. The anti-FX antibody or antigen-binding portion thereof of any one of embodiments 66 to 105, wherein the antibody is selected from the group consisting of IgG1, IgG2, IgG3, IgG4, or a variant thereof.

[0145] Embodiment 107. The anti-FX antibody or antigen-binding portion thereof of embodiment 106, wherein the antibody is an IgG4 antibody.

[0146] Embodiment 108. The antibody of embodiment 10, wherein the antibody comprises an effector-less IgG4 Fc. 6. An anti-FX antibody or antigen-binding portion thereof.

[0147] Embodiment 109. The anti-FX antibody or antigen-binding portion thereof of any one of embodiments 66 to 108, comprising a heavy chain constant region.

[0148] Embodiment 110. The anti-FX antibody of any one of embodiments 66 to 109, wherein the antibody is a human antibody, an engineered antibody, or a humanized antibody.

[0149] Embodiment 111. The anti-FX antigen-binding portion of any one of embodiments 66 to 110, wherein the antigen-binding portion comprises a Fab, a Fab', a F(ab')2, an Fv, or a single-chain Fv (scFv).

[0150] Embodiment 112. A bispecific molecule comprising the anti-FX antibody of any one of embodiments 66 to 111 linked to a molecule with a second binding specificity.

[0151] Embodiment 113. A nucleic acid encoding the heavy and / or light chain variable region of the antibody, or antigen-binding portion thereof, of any one of embodiments 66 to 111, or the bispecific molecule of embodiment 112.

[0152] Embodiment 114. An expression vector comprising the nucleic acid molecule of embodiment 113.

[0153] Embodiment 115. A cell transformed with the expression vector of embodiment 114.

[0154] Embodiment 116. An immunoconjugate comprising the antibody or antigen-binding portion thereof of any one of embodiments 66 to 111, or the bispecific molecule of embodiment 112, wherein the immunoconjugate is linked to an agent.

[0155] Embodiment 117. A composition comprising the antibody or antigen-binding portion thereof of any one of embodiments 66 to 111, or the bispecific molecule of embodiment 112, or the immunoconjugate of embodiment 116, and a carrier.

[0156] Embodiment 118. A kit comprising the antibody or antigen-binding portion thereof of any one of embodiments 66 to 111, or the bispecific molecule of embodiment 112, or the immunoconjugate of embodiment 116, and instructions for use.

[0157] Embodiment 119. A method of producing an anti-FX antibody or antigen-binding portion thereof, comprising expressing the antibody or antigen-binding portion thereof in a cell of embodiment 115, and isolating the antibody or antigen-binding portion thereof from the cell.

[0158] Embodiment 120. Provided is a method for measuring zymogen FX (FXz) in a subject in need thereof, comprising contacting an anti-FX antibody, or antigen-binding portion thereof, of any one of embodiments 66 to 111 with a sample obtained from the subject under suitable conditions, and measuring binding of the anti-FX antibody, or antigen-binding portion thereof, to FXz in the sample.

[0159] Embodiment 121. The method of embodiment 120, wherein the sample is blood or serum from the subject.

[0160] Embodiment 122. An anti-FIX antibody or antigen-binding portion thereof of any one of embodiments 1 to 55 and embodiments 169 to 204, and (ii) an anti-FIX antibody or antigen-binding portion thereof of any one of embodiments 66 to 111. A bispecific molecule comprising any one anti-FX antibody or antigen-binding portion thereof.

[0161] Embodiment 123. The bispecific molecule of embodiment 122, which cross-competes with a reference bispecific antibody, wherein the reference bispecific antibody comprises the VH and VL of an anti-FIX antibody selected from the group consisting of the anti-FIX antibodies in Figures 3A, 3B, 3C and 3D, and the VH and VL of an anti-FX antibody selected from the group consisting of the anti-FX antibodies in Figures 12A, 12B and 12C.

[0162] Embodiment 124. The bispecific molecule of embodiment 122 or 123, which binds to the same epitope as the reference bispecific antibody, wherein the reference bispecific antibody comprises the VH and VL of an anti-FIX antibody selected from the group consisting of the anti-FIX antibodies in Figures 3A, 3B, 3C and 3D, and the VH and VL of an anti-FX antibody selected from the group consisting of the anti-FX antibodies in Figures 12A, 12B and 12C.

[0163] Embodiment 125. (i) an anti-FIX antibody or antigen-binding portion thereof comprises VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, wherein the VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3 are selected from the group consisting of VH CDR1, VH CDR2, and VH CDR3, and VL CDR1, VL CDR2, and VL CDR3 of the anti-FIX (BIIB-9) antibody in Figure 16A, Figure 16B, Figure 16C, and Figure 16D; and (ii) The bispecific molecule of any one of embodiments 122 to 124, wherein the anti-FX antibody or antigen-binding portion thereof comprises VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, and the VH CDR1, CDR2 and CDR3, and the VL CDR1, CDR2 and CDR3 are selected from the group consisting of VH CDR1, VH CDR2 and VH CDR3, and VL CDR1, VL CDR2 and VL CDR3 of the anti-FX (BIIB-12) antibody in Figures 16A, 16B, 16C, and 16D.

[0164] Embodiment 126. (a) an anti-FIX antibody, or antigen-binding portion thereof, (a1) VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NO: 815, 860 or 905, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 950, 995 or 1040, respectively (BIIB-9-484); (a2) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 822, 867, and 912, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 957, 1002, and 1047, respectively (BIIB-9-619); (a3) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1347, 1351, and 1355, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1359, 1363, and 1367, respectively (BIIB-9-578); (a4) VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NOs: 843, 888 and 933, respectively, and / or VL CDR1, CDR2 and CDR3 sequences comprising SEQ ID NOs: 978, 1023 and 1068, respectively (BIIB-9-1335); or (a5) comprising VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 844, 889, and 934, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 979, 1024, and 1069, respectively (BIIB-9-1336); (b) an anti-FX antibody, or antigen-binding portion thereof, (b1) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1393, 1483, and 1573, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1663, 1753, and 1843, respectively (BIIB-12-915); (b2) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1395, 1485, and 1575, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1665, 1755, and 1845, respectively (BIIB-12-917); (b3) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1911, 1915, and 1919, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1923, 1927, and 1931, respectively (BIIB-12-925); (b4) VH CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1409, 1499, and 1589, respectively, and / or VL CDR1, CDR2, and CDR3 sequences comprising SEQ ID NOs: 1679, 1769, and 1859, respectively (BIIB-12-932); or (b5) The bispecific molecule of any one of embodiments 122 to 124, comprising VH CDR1, CDR2 and CDR3 sequences comprising SEQ ID NOs: 1433, 1523 and 1613, respectively, and / or VL CDR1, CDR2 and CDR3 sequences comprising SEQ ID NOs: 1703, 1793 and 1883, respectively (BIIB-12-1306).

[0165] Embodiment 127. (a) an anti-FIX antibody, or antigen-binding portion thereof, comprising: (a1) VH and VL comprising SEQ ID NOs: 31 and 221, respectively (BIIB-9-484); (a2) VH and VL comprising SEQ ID NOs: 45 and 235, respectively (BIIB-9-619); (a3) VH and VL comprising SEQ ID NOs: 185 and 371, respectively (BIIB-9-578); (a4) VH and VL comprising SEQ ID NOs: 87 and 221, respectively (BIIB-9-1335); or (a5) VH and VL (BIIB-9-1336) comprising SEQ ID NOs: 89 and 221, respectively; (b) an anti-FX antibody, or antigen-binding portion thereof, (b1) VH and VL comprising SEQ ID NOs: 423 and 611, respectively (BIIB-12-915); (b2) VH and VL comprising SEQ ID NOs: 427 and 615, respectively (BIIB-12-917); (b3) VH and VL comprising SEQ ID NOs: 559 and 747, respectively (BIIB-12-925); (b4) VH and VL comprising SEQ ID NOs: 455 and 643, respectively (BIIB-12-932); or (b5) The bispecific molecule of any one of embodiments 122 to 124, comprising a VH and a VL (BIIB-12-1306) comprising SEQ ID NOs: 503 and 691, respectively.

[0166] Embodiment 128. (i) the anti-FIX antibody or antigen-binding portion thereof comprises a VH and a VL (BIIB-9-484) comprising SEQ ID NOs: 31 and 221, respectively, and the anti-FX antibody or antigen-binding portion thereof comprises a VH and a VL (BIIB-12-915) comprising SEQ ID NOs: 423 and 611, respectively; (ii) an anti-FIX antibody or antigen-binding portion thereof comprising a VH and a VL (BIIB-9-484) comprising SEQ ID NOs: 31 and 221, respectively; the portion comprises a VH and VL (BIIB-12-917) comprising SEQ ID NOs: 427 and 615, respectively; (iii) the anti-FIX antibody, or antigen-binding portion thereof, comprises a VH and a VL comprising SEQ ID NOs: 31 and 221, respectively (BIIB-9-484), and the anti-FX antibody, or antigen-binding portion thereof, comprises a VH and a VL comprising SEQ ID NOs: 559 and 747, respectively (BIIB-12-925); (iv) the anti-FIX antibody, or antigen-binding portion thereof, comprises a VH and a VL comprising SEQ ID NOs: 31 and 221, respectively (BIIB-9-484), and the anti-FX antibody, or antigen-binding portion thereof, comprises a VH and a VL comprising SEQ ID NOs: 455 and 643, respectively (BIIB-12-932); (v) the anti-FIX antibody, or antigen-binding portion thereof, comprises a VH and a VL comprising SEQ ID NOs: 185 and 371, respectively (BIIB-9-578), and the anti-FX antibody, or antigen-binding portion thereof, comprises a VH and a VL comprising SEQ ID NOs: 423 and 611, respectively (BIIB-12-915); (vi) the anti-FIX antibody, or antigen-binding portion thereof, comprises a VH and a VL comprising SEQ ID NOs: 185 and 371, respectively (BIIB-9-578), and the anti-FX antibody, or antigen-binding portion thereof, comprises a VH and a VL comprising SEQ ID NOs: 427 and 615, respectively (BIIB-12-917); (vii) an anti-FIX antibody, or antigen-binding portion thereof, comprising a VH and a VL comprising SEQ ID NOs: 45 and 235, respectively (BIIB-9-619), and an anti-FX antibody, or antigen-binding portion thereof, comprising a VH and a VL comprising SEQ ID NOs: 427 and 615, respectively (BIIB-12-917); or (viii) The bispecific molecule of any one of embodiments 122 to 127, wherein the anti-FIX antibody or antigen-binding portion thereof comprises a VH and a VL comprising SEQ ID NOs: 45 and 235, respectively (BIIB-9-619), and the anti-FX antibody or antigen-binding portion thereof comprises a VH and a VL comprising SEQ ID NOs: 559 and 747, respectively (BIIB-12-925).

[0167] Embodiment 129. The bispecific molecule of any one of embodiments 122 to 128, which functionally mimics activated factor VIII (FVIIIa) cofactor in at least one FVIIIa activity assay.

[0168] Embodiment 130. The bispecific molecule of embodiment 129, wherein the FVIIIa activity assay is selected from a chromogenic FXa generation assay, a one-stage clotting assay, or a combination thereof.

[0169] Embodiment 131. The bispecific molecule of embodiment 129 or 130, wherein the FVIIIa activity achieves at least 10%, 20%, 30%, 35%, 40%, 45%, 50%, 60%, 70%, 80%, 90%, 100%, 110%, 120%, 130%, 140%, 150%, 160%, 170%, 180%, 190% or 200% of the activity otherwise achieved by FVIII in the same assay.

[0170] Embodiment 132. The bispecific molecule of any one of embodiments 122 to 131, which is capable of generating thrombin from prothrombin, fibrin from fibrinogen, and / or a fibrin clot in vitro or in vivo.

[0171] Embodiment 133. A bispecific molecule according to any one of embodiments 122 to 132, which simultaneously binds to both FIXa and FX as determined by BLI.

[0172] Embodiment 134. The bispecific molecule of any one of embodiments 122 to 133, which is an IgG isotype.

[0173] Embodiment 135. The bispecific molecule of embodiment 134, wherein the IgG isotype is an IgG1 subclass.

[0174] Embodiment 136. The bispecific molecule of embodiment 134, wherein the IgG isotype is an IgG4 part class.

[0175] Embodiment 137. The bispecific molecule of any one of embodiments 122 to 136, which is in a bispecific IgG format and is selected from the group consisting of the antibodies in Table 2.

[0176] Embodiment 138. The bispecific molecule of embodiment 137, which is a bispecific heterodimeric format.

[0177] Embodiment 139. The bispecific molecule of any one of embodiments 122 to 138, comprising two different heavy chains and two different light chains.

[0178] Embodiment 140. A bispecific molecule according to any one of embodiments 122 to 138, comprising two identical light chains and two different heavy chains.

[0179] Embodiment 141 The bispecific molecule of any one of embodiments 122 to 140, wherein the bispecific molecule is capable of controlling or reducing the incidence of bleeding episodes in a subject with hemophilia.

[0180] Embodiment 142. The bispecific molecule of any one of embodiments 122 to 140, which is capable of maintaining homeostasis in a subject with hemophilia.

[0181] Embodiment 143. The bispecific molecule of any one of embodiments 122 to 140, which is capable of achieving routine prophylaxis in subjects with hemophilia.

[0182] Embodiment 144 The bispecific molecule of any one of embodiments 122 to 143, wherein the subject develops or is expected to develop neutralizing antibodies against Factor VIII.

[0183] Embodiment 145. An immunoconjugate comprising the bispecific molecule of any one of embodiments 122 to 144, wherein the immunoconjugate is linked to an agent.

[0184] Embodiment 146. A composition comprising the bispecific molecule of any one of embodiments 122 to 144, or the immunoconjugate of embodiment 145, and a carrier.

[0185] Embodiment 147. A kit comprising the bispecific molecule of any one of embodiments 122 to 144, or the immunoconjugate of embodiment 145, and instructions for use.

[0186] Embodiment 148. A nucleic acid sequence encoding the bispecific molecule of any one of embodiments 122 to 144.

[0187] Embodiment 149. A vector comprising the nucleic acid of embodiment 148.

[0188] Embodiment 150. A host cell comprising the vector of embodiment 149.

[0189] Embodiment 151. The host cell of embodiment 150, wherein the host cell is a prokaryotic cell, a eukaryotic cell, a protist cell, an animal cell, a plant cell, a fungal cell, a yeast cell, an Sf9 cell, a mammalian cell, an avian cell, an insect cell, a CHO cell, an HEK cell, or a COS cell.

[0190] Embodiment 152. A method of producing a bispecific molecule, comprising culturing the host cell of embodiment 150 under conditions that allow expression of the bispecific molecule.

[0191] Embodiment 153. A method of producing the bispecific molecule of any one of embodiments 122 to 144, further comprising conditions that enhance heterodimerization.

[0192] Embodiment 154. A method for promoting FX activation in a subject in need thereof, comprising administering to the subject a therapeutically effective amount of the bispecific molecule of any one of embodiments 122 to 144, the immunoconjugate of embodiment 145, the composition of embodiment 146, the nucleic acid of embodiment 148, the vector of embodiment 149, or the host cell of embodiment 150.

[0193] Embodiment 155. A method for reducing the frequency or severity of bleeding episodes in a subject in need thereof, comprising administering to the subject an effective amount of the bispecific molecule of any one of embodiments 122 to 144, the immunoconjugate of embodiment 145, the composition of embodiment 146, the nucleic acid of embodiment 148, the vector of embodiment 149, or the host cell of embodiment 150.

[0194] Embodiment 156 The method of embodiment 155, wherein the subject has developed or is prone to developing an inhibitor to factor VIII ("FVIII").

[0195] Embodiment 157 The method of embodiment 156, wherein the inhibitor against FVIII is a neutralizing antibody against FVIII.

[0196] Embodiment 158. The method of any one of embodiments 155 to 157, wherein the bleeding episode is the result of hemarthrosis, muscle bleeding, oral bleeding, bleeding, bleeding into muscle, oral bleeding, trauma, head trauma, gastrointestinal bleeding, intracranial bleeding, intra-abdominal bleeding, intrathoracic bleeding, fracture, central nervous system bleeding, bleeding in the retropharyngeal space, bleeding in the retroperitoneal space, bleeding in the iliopsoas sheath, or any combination thereof.

[0197] Embodiment 159. A method of treating a blood coagulation disorder in a subject in need thereof, comprising administering to the subject an effective amount of the bispecific molecule of any one of embodiments 122 to 144, the immunoconjugate of embodiment 145, the composition of embodiment 146, the nucleic acid of embodiment 148, the vector of embodiment 149, or the host cell of embodiment 150.

[0198] Embodiment 160. The method of embodiment 159, wherein the blood clotting disorder is hemophilia A or hemophilia B.

[0199] Embodiment 161. The method of any one of embodiments 154 to 160, wherein the subject is a human subject.

[0200] Embodiment 162 The method of any one of embodiments 154 to 160, wherein the subject is undergoing or has received FVIII replacement therapy.

[0201] Embodiment 163 The method of any one of embodiments 154 to 162, wherein the bispecific molecule is administered in combination with hemophilia therapy.

[0202] Embodiment 164. The method of embodiment 163, wherein the hemophilia therapy is FVIII replacement therapy. .

[0203] Embodiment 165 The method of embodiment 163 or 164, wherein the bispecific molecule is administered before, during, or after administration of hemophilia therapy.

[0204] Embodiment 166 The method of any one of embodiments 154 to 165, wherein the bispecific molecule is administered intravenously or subcutaneously.

[0205] Embodiment 167 The method of any one of embodiments 154 to 166, wherein administration of the bispecific molecule reduces the occurrence of bleeding episodes, the frequency of spontaneous bleeding episodes, or acute bleeding.

[0206] Embodiment 168. The method of embodiment 167, wherein administration of the bispecific molecule reduces the annual bleeding rate by 5%, 10%, 20%, 30%, or 50%.

[0207] Embodiment 169. An anti-FIXa antibody or antigen-binding portion thereof that binds to the same epitope as BIIB-9-1336.

[0208] Embodiment 170. An anti-FIXa antibody or antigen-binding portion thereof that binds to an epitope that overlaps with the BIIB-9-1336 epitope.

[0209] Embodiment 171. An anti-FIXa antibody or antigen-binding portion thereof, which binds to an epitope region comprising at least one amino acid located between positions (i) 91 and 101, (ii) 125 and 128, (iii) 165 and 179, or (iv) 232 and 241 according to the chymotrypsinogen numbering system in the sequence of the heavy chain of FIXa.

[0210] Embodiment 172. An anti-FIXa antibody or antigen-binding portion thereof, which binds to an epitope comprising at least one of amino acid residues H91, H92, N93, H101, D125, K126, E127, Y128, R165, Y177, N178, N179, S232, R233, Y234, V235, N236, W237, E240 and K241 according to chymotrypsinogen numbering of the sequence of the heavy chain of FIXa.

[0211] Embodiment 173. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 171 or 172, wherein the epitope comprises amino acid residues N93, R165, N178 and R233 according to the chymotrypsinogen numbering system of the heavy chain of FIXa.

[0212] Embodiment 174. The anti-FIXa antibody or antigen-binding portion thereof of embodiments 171 to 173, wherein the epitope comprises amino acid residues H91, H92, N93, H101, D125, K126, E127, Y128, R165, Y177, N178, N179, S232, R233, Y234, V235, N236, W237, E240 and K241 according to chymotrypsinogen numbering of the sequence of the heavy chain of FIXa.

[0213] Embodiment 175. The anti-FIXa antibody or antigen-binding portion thereof of embodiments 171 to 174, wherein the epitope does not include at least one of amino acid residues N100, K132, Y137, R170, T172, F174, T175, H185, E202 and G205 according to the chymotrypsinogen numbering system of the heavy chain sequence of FIXa.

[0214] Embodiment 176. The method of any one of embodiments 171 to 171, wherein the epitope does not include amino acid residues N100, K132, Y137, R170, T172, F174, T175, H185, E202 and G205 of the sequence of the heavy chain of FIXa according to the chymotrypsinogen numbering system. 5. An anti-FIXa antibody or an antigen-binding portion thereof.

[0215] Embodiment 177. The anti-FIXa antibody or antigen-binding portion thereof of embodiments 171 to 176, which binds to at least one amino acid residue in the light chain of FIXa (SEQ ID NO: 756).

[0216] Embodiment 178. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 177, wherein the amino acid residue in the light chain of FIXa (SEQ ID NO: 756) is K100.

[0217] Embodiment 179. The anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 169 to 178, wherein the epitope overlaps the binding site of FVIIIa to FIXa.

[0218] Embodiment 180 The anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 169 to 179, which cross-competes with FVIIIa for binding to FIXa.

[0219] Embodiment 181 The anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 169 to 180, which blocks the binding of FVIIIa to FIXa.

[0220] Embodiment 182. A polypeptide that specifically binds to FIXa and comprises a VH CDR1, CDR2 and CDR3, and a VL CDR1, CDR2 and CDR3, (i) the VH CDR1 comprises a VH CDR1 selected from the group consisting of a VH CDR1 in Table 7 or a VH CDR1 having one or two mutations; and / or (ii) the VH CDR2 comprises a VH CDR2 selected from the group consisting of a VH CDR2 in Table 7 or a VH CDR2 having one or two mutations; and / or (iii) the VH CDR3 comprises a VH CDR3 selected from the group consisting of a VH CDR3 in Table 7 or a VH CDR3 having one or two mutations; and / or (iv) the VL CDR1 comprises a VL CDR1 selected from the group consisting of a VL CDR1 in Table 7 or a VL CDR1 having one or two mutations; and / or (v) the VL CDR2 comprises a VL CDR2 selected from the group consisting of a VL CDR2 in Table 7 or a VL CDR2 having one or two mutations; and / or (vi) The VL CDR3 comprises a VL CDR3 selected from the group consisting of a VL CDR3 in Table 7 or a VL CDR3 having one or two mutations. 13. The anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 1 to 12.

[0221] Embodiment 183. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 182, which specifically binds to FIXa and comprises VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, wherein VH CDR3 comprises the amino acid sequence ARDX1GGYAGYYGMDV (sequence number 2196), and X1 is L or V.

[0222] Embodiment 184. (i) VH CDR1 comprises the amino acid sequence FTFX1SX2X3MX4 (SEQ ID NO: 2194), wherein X1 is S, G, or E, X2 is Y or F, X3 is S, E, G, or D, and X4 is N, V, A, or T; and / or (ii) VH CDR2 has the amino acid sequence X5ISX6X7X8X9X 10 X5 is S, A, Y, or G, X6 is S or A, X7 is S, A, or G, X8 is S, G, or D, X9 is S, T, or G, and X 10is Y or T.

[0223] Embodiment 185. The antibody of embodiment 182 or any one of the preceding claims, comprising VL CDR1, CDR2, and CDR3, wherein VL CDR3 comprises the amino acid sequence QQYANFPYT (SEQ ID NO: 2168). 184. Any one of the isolated anti-FIXa antibodies or antigen-binding portions thereof.

[0224] Embodiment 186. A VL comprising CDR1, CDR2 and CDR3, (i) the VL CDR1 comprises the amino acid sequence QASQDIANYLN (SEQ ID NO: 2116); and / or (ii) The isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 185, wherein the VL CDR2 comprises the amino acid sequence DASNLET (SEQ ID NO: 2142).

[0225] Embodiment 187. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 182, comprising a VH CDR1, CDR2 and CDR3 comprising a VH CDR1 selected from SEQ ID NOs: 2038 to 2047, a VH CDR2 selected from SEQ ID NOs: 2064 to 2073 and a VH CDR3 selected from SEQ ID NOs: 2090 to 2099, and / or a VL CDR1, CDR2 and CDR3 comprising a VL CDR1 selected from SEQ ID NOs: 2116 to 2125, a VL CDR2 selected from SEQ ID NOs: 2142 to 2151 and a VL CDR3 selected from SEQ ID NOs: 2168 to 2177.

[0226] Embodiment 188. An isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 182, which specifically binds to FIXa and comprises VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, wherein VH CDR3 comprises the amino acid sequence X1RDVX2GYAGX3YGMDV (sequence number 2198), wherein X1 is A or V, X2 is G or S, and X3 is Y or F.

[0227] Embodiment 189. (i) VH CDR1 comprises the amino acid sequence FTFGSYDMN (SEQ ID NO: 2048); and / or (ii) An isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 188, wherein VH CDR2 comprises the amino acid sequence SISX1X2X3SYIX4YAX5SVKG (sequence number 2197), wherein X1 is S or D, X2 is G or S, X3 is E or A, X4 is Y or A, and X5 is E or D.

[0228] Embodiment 190. An isolated anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 182, 188 or 189, which specifically binds to FIXa and comprises VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, wherein VL CDR3 comprises the amino acid sequence X1QYAX2FPYT (sequence number 2201), wherein X1 is Q or S, and X2 is N or R.

[0229] Embodiment 191. A VL comprising CDR1, CDR2 and CDR3, (i) VL CDR1 comprises the amino acid sequence X1AX2X3X4IX5X6YLN (SEQ ID NO: 2199), wherein X1 is Q, G, or E, X2 is S or N, X3 is Q or E, X4 is D or Y, X5 is A or S, and X6 is N or D; and / or (ii) The isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 190, wherein the VL CDR2 is the amino acid sequence DAX7NLX8X9 (sequence number 2200), wherein X7 is S or A, X8 is E, H or Q, and X9 is T or Y.

[0230] Embodiment 192. A VH CDR1, CDR2 and CDR3 comprising a VH CDR1 selected from SEQ ID NOs: 2048 to 2052, a VH CDR2 selected from SEQ ID NOs: 2074 to 2078 and a VH CDR3 selected from SEQ ID NOs: 2100 to 2104, and / or a VL CDR1 selected from SEQ ID NOs: 2126 to 2130, a VL CDR2 selected from SEQ ID NOs: 2152 to 2156 and a VL CDR3 selected from SEQ ID NOs: 2178 to 2182. 183. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 182, comprising a VL CDR1, CDR2 and CDR3 comprising a selected VL CDR3.

[0231] Embodiment 193. The isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 182, which specifically binds to FIXa and comprises VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, wherein VH CDR3 comprises the amino acid sequence ARDGPX1X2X3DYYMDV (sequence number 2204), wherein X1 is R or Q, X2 is V, D, L or E, and X3 is S or V.

[0232] Embodiment 194. A VH comprising CDR1, CDR2 and CDR3, (i) VH CDR1 comprises the amino acid sequence YTFX1X2YX3MH (SEQ ID NO: 2202), wherein Xi is T or H, X2 is S, G, or H, and X3 is Y or P; and / or (ii) An isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 193, wherein VH CDR2 comprises the amino acid sequence X4INPSX5GX6TX7YAQKFQG (sequence number 2203), wherein X4 is I or S, X5 is G or R, X6 is S or R, and X7 is S or E.

[0233] Embodiment 195. An isolated anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 182, 193, or 194, which specifically binds to FIXa and comprises VH CDR1, CDR2, and CDR3, and VL CDR1, CDR2, and CDR3, wherein VL CDR3 comprises the amino acid sequence QQRDNWPFT (sequence number 2116).

[0234] Embodiment 196. A VL comprising CDR1, CDR2 and CDR3, (i) the VL CDR1 comprises the amino acid sequence RASQSVSSYLA (SEQ ID NO: 2116); and / or (ii) The isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 195, wherein the VL CDR2 comprises the amino acid sequence DASNRAT (SEQ ID NO: 2116).

[0235] Embodiment 197. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 182, comprising a VH CDR1, CDR2 and CDR3 comprising a VH CDR1 selected from SEQ ID NOs: 2053 to 2057, a VH CDR2 selected from SEQ ID NOs: 2079 to 2083 and a VH CDR3 selected from SEQ ID NOs: 2105 to 2109, and / or a VL CDR1, CDR2 and CDR3 comprising a VL CDR1 selected from SEQ ID NOs: 2131 to 2135, a VL CDR2 selected from SEQ ID NOs: 2157 to 2161 and a VL CDR3 selected from SEQ ID NOs: 2183 to 2187.

[0236] Embodiment 198. The isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 182, which specifically binds to FIXa and comprises VH CDR1, CDR2 and CDR3, and VL CDR1, CDR2 and CDR3, wherein VH CDR3 comprises the amino acid sequence ARDKYQDYSX1DI (sequence number 2207), and X1 is F or V.

[0237] Embodiment 199. A VH comprising CDR1, CDR2 and CDR3, (i) VH CDR1 comprises the amino acid sequence GSIX1SX2X3YX4WX5 (SEQ ID NO: 2205), wherein Xi is S or A, X2 is S, T, G, or V, X3 is S or A, X4 is Y or A, and X5 is G, V, N, or S; and / or (ii) VH CDR2 has the amino acid sequence X6IX7X8X9GX 10 TX 11 X6 is S or Y, X7 is S, Y, R, T or Q, X8 is Y, G, P or A, X9 is S or Q, and X 10 is S or K, and X 11 is Y or Q.

[0238] Embodiment 200. The isolated anti-FIXa antibody of embodiment 182, 198 or 199, comprising a VL CDR1, CDR2 and CDR3, wherein VL CDR3 comprises the amino acid sequence QQANFLPFT (sequence number 2188).

[0239] Embodiment 201. A VL comprising CDR1, CDR2 and CDR3, (i) VL CDR1 comprises the amino acid sequence RASQGIDSWLA (SEQ ID NO: 2136); and / or (ii) The isolated anti-FIXa antibody or antigen-binding portion thereof of embodiment 200, wherein the VL CDR2 comprises the amino acid sequence AASSLQS (sequence number 2162).

[0240] Embodiment 202. The anti-FIXa antibody or antigen-binding portion thereof of embodiment 182, comprising a VH CDR1, CDR2 and CDR3 comprising a VH CDR1 selected from SEQ ID NOs: 2058 to 2063, a VH CDR2 selected from SEQ ID NOs: 2084 to 2089 and a VH CDR3 selected from SEQ ID NOs: 2110 to 2115, and / or a VL CDR1, CDR2 and CDR3 comprising a VL CDR1 selected from SEQ ID NOs: 2136 to 2141, a VL CDR2 selected from SEQ ID NOs: 2162 to 2167, and a VL CDR3 selected from SEQ ID NOs: 2188 to 2193.

[0241] Embodiment 203. Comprising VH and VL, (i) the VH comprises an amino acid sequence at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or about 100% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 1935, 1939, 1943, 1947, 1951, 1955, 1959, 1963, 1967, 1971, 1975, 1979, 1983, 1987, 1991, 1995, 1999, 2003, 2007, 2011, 2015, 2019, 2023, 2027, 2031, and 2035; and / or (ii) The anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 182 to 202, wherein the VL comprises an amino acid sequence at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99% or about 100% identical to an amino acid sequence selected from the group consisting of SEQ ID NOs: 1937, 1941, 1945, 1949, 1953, 1957, 1961, 1965, 1969, 1973, 1977, 1981, 1985, 1989, 1993, 1997, 2001, 2005, 2009, 2013, 2017, 2021, 2025, 2029, 2033 and 2037.

[0242] Embodiment 204. Comprising VH and VL, (a1) VH and VL comprise SEQ ID NOs: 1935 and 1937 (BIIB-9-3595), respectively; (a2) VH and VL comprise SEQ ID NOs: 1939 and 1941 (BIIB-9-3601), respectively; (a3) VH and VL comprise SEQ ID NOs: 1943 and 1945 (BIIB-9-3604), respectively; (a4) VH and VL comprise SEQ ID NOs: 1947 and 1949 (BIIB-9-3617), respectively; (a5) VH and VL comprise SEQ ID NOs: 1951 and 1953 (BIIB-9-3618), respectively; (a6) VH and VL are SEQ ID NOs: 1955 and 1957 (BIIB-9 -3621); (a7) VH and VL comprise SEQ ID NOs: 1959 and 1961 (BIIB-9-3647), respectively; (a8) VH and VL comprise SEQ ID NOs: 1963 and 1965 (BIIB-9-3649), respectively; (a9) VH and VL comprise SEQ ID NOs: 1967 and 1969 (BIIB-9-3650), respectively; (a10) VH and VL comprise SEQ ID NOs: 1971 and 1973 (BIIB-9-3654), respectively; (a11) VH and VL comprise SEQ ID NOs: 1975 and 1977 (BIIB-9-3753), respectively; (a12) VH and VL comprise SEQ ID NOs: 1979 and 1981 (BIIB-9-3754), respectively; (a13) VH and VL comprise SEQ ID NOs: 1983 and 1985 (BIIB-9-3756), respectively; (a14) VH and VL comprise SEQ ID NOs: 1987 and 1989 (BIIB-9-3764), respectively; (a15) VH and VL comprise SEQ ID NOs: 1991 and 1993 (BIIB-9-3766), respectively; (a16) VH and VL comprise SEQ ID NOs: 1995 and 1997 (BIIB-9-3707), respectively; (a17) VH and VL comprise SEQ ID NOs: 1999 and 2001 (BIIB-9-3709), respectively; (a18) VH and VL comprise SEQ ID NOs: 2003 and 2005 (BIIB-9-3720), respectively; (a19) VH and VL comprise SEQ ID NOs: 2007 and 2009 (BIIB-9-3727), respectively; (a20) VH and VL comprise SEQ ID NOs: 2011 and 2013 (BIIB-9-3745), respectively; (a21) VH and VL comprise SEQ ID NOs: 2015 and 2017 (BIIB-9-3780), respectively; (a22) VH and VL comprise SEQ ID NOs: 2019 and 2021 (BIIB-9-3675), respectively; (a23) VH and VL comprise SEQ ID NOs: 2023 and 2025 (BIIB-9-3681), respectively; (a24) VH and VL comprise SEQ ID NOs: 2027 and 2029 (BIIB-9-3684), respectively; (a25) VH and VL comprise SEQ ID NOs: 2031 and 2033 (BIIB-9-3698), respectively; or (a26) The anti-FIXa antibody or antigen-binding portion thereof of any one of embodiments 182 to 203, wherein VH and VL comprise SEQ ID NOs: 2035 and 2037 (BIIB-9-3704), respectively. [Brief explanation of the drawings]

[0243] [Figure 1A] FIG. 1 Schematic representation of the domain organization of FIX zymogen and activated FIX (FIXa+EGR-CMK), with and without pseudosubstrate bound to the active site (free FIXa and FIXa-SM, respectively). [Figure 1B]Schematic diagram of the domain organization of FIX zymogen and activated FIX, with and without a pseudosubstrate bound to the active site (FXa+EGR-CMK). In this diagram, HC is the heavy chain of FIX, FIXa, FX, or FXa. LC is the light chain of FIX, FIXa, FX, or FXa. [Figure 2] FIG. 1 is a schematic diagram of antibody generation, antibody characterization, and functional characterization for certain embodiments described herein. [Figure 3-1] Figures 3A-3D are tables listing 95 anti-FIX antibodies disclosed herein that were discovered using the antibody generation method described in Figure 2. The germline, CDR length, CDR amino acid sequence, and SEQ ID NO for both the VH and VL of the antibodies are provided. The full VH and VL sequences are provided in Table 4. The SEQ ID NO for each CDR sequence is shown in Table 4. Figures 3A-3C represent antibodies that preferentially bind activated coagulation factor IX (FIXa) (e.g., free FIXa and / or FIXa covalently modified with EGR- or LTR-CMK (FIXa-SM)) compared to FIX zymogen (e.g., nonactivatable FIX). In particular, Figure 3A lists antibodies that preferentially bind FIXa-SM compared to free FIXa or FIXa zymogen (e.g., nonactivatable FIX) (Class I). Figure 3B lists antibodies that bind preferentially to free FIXa (e.g., nonactivatable FIX) compared to FIXa-SM or FIX zymogen (Class II). Figure 3C lists antibodies that bind either FIXa-SM or free FIXa, but bind less to FIX zymogen (e.g., nonactivatable FIX) (Class III). Figure 3D lists antibodies that bind preferentially to FIX zymogen (e.g., nonactivatable FIX) compared to free FIXa or FIXa-SM (Class IV). [Figure 3-2] Continued from Figure 3-1. [Figure 3-3] Continued from Figure 3-2. [Figure 3-4] Continued from Figure 3-3. [Figure 4A]Figure 1 shows the binding of sensor-bound IgG to the indicated antigen, FIX zymogen (e.g., nonactivatable FIX) (Haematologic Technologies, Inc., Essex Junction, VT, USA) or FIXa (Haematologic Technologies, Inc., Essex Junction, VT, USA) as measured by biolayer interferometry (BLI). The maximum BLI response (nm) for each antibody is plotted on the y-axis. [Figure 4B] Figure 1 shows the binding of sensor-bound IgG to the indicated antigen, FIX zymogen (e.g., nonactivatable FIX) (Haematologic Technologies, Inc., Essex Junction, VT, USA) or FIXa (Haematologic Technologies, Inc., Essex Junction, VT, USA) as measured by biolayer interferometry (BLI). The maximum BLI response (nm) for each antibody is plotted on the y-axis. [Figure 5] 1 is a table presenting the apparent monovalent affinity values ​​(KD) to free FIXa for each of the listed antibodies as determined by the 1:1 fitting algorithm provided in ForteBio Data Analysis 9.0 software. [Figure 6-1]Figures 6A-6E are graphs showing BLI binding measurements of IgG bound to sensors with indicated antigens (free FIXa or FIX zymogen (e.g., nonactivatable FIX)). Figure 6A shows binding measurements of antibody BIIB-9-484 (VH: SEQ ID NO: 31; VL: SEQ ID NO: 221). Figure 6B shows binding measurements of antibody BIIB-9-440 (VH: SEQ ID NO: 19; VL: SEQ ID NO: 209). Figure 6C shows binding measurements of antibody BIIB-9-882 ​​(VH: SEQ ID NO: 115; VL: SEQ ID NO: 301). Figure 6D shows binding measurements of antibody BIIB-9-460 (VH: SEQ ID NO: 23; VL: SEQ ID NO: 213). Figure 6E shows binding measurements of antibody BIIB-9-433 (VH: SEQ ID NO: 127; VL: SEQ ID NO: 313). These plots show the BLI response (nm) for binding and dissociation as a function of time. [Figure 6-2] Continued from Figure 6-1. [Figure 6-3] Continued from Figure 6-2. [Figure 6-4] Continued from Figure 6-3. [Figure 6-5] Continued from Figure 6-4. [Figure 6-6] Figure 6F provides a table of apparent monovalent affinities (KD) for FIX zymogen (e.g., nonactivatable FIX) and free FIXa for each of the listed antibodies (i.e., BIIB-9-484, BIIB-9-440, BIIB-9-882, BIIB-9-460, and BIIB-9-433) described in Figures 6A-6E, respectively, as determined by the 1:1 fitting algorithm provided in ForteBio Data Analysis 9.0 software. [Figure 7]Graph showing antibody measurements by BLI of sensor-bound IgG to the indicated antigens, free FIXa (Haematologic Technologies, Inc., Essex Junction, VT, USA) or FIXa-SM (e.g., FIXa+EGR-CMK (Haematologic Technologies, Inc., Essex Junction, VT, USA)). The maximum BLI response (nm) for each antibody is plotted on the y-axis. [Figure 8-1] Figures 8A-8E are graphs showing BLI binding measurements of sensor-bound IgG to the indicated antigens (FIXa-SM, e.g., FIXa + EGF-CMK, and free FIXa). Figure 8A shows binding measurements of antibody BIIB-9-484 (VH: SEQ ID NO: 31; VL: SEQ ID NO: 221). Figure 8B shows binding measurements of antibody BIIB-9-440 (VH: SEQ ID NO: 19; VL: SEQ ID NO: 209). Figure 8C shows binding measurements of antibody BIIB-9-882 ​​(VH: SEQ ID NO: 115; VL: SEQ ID NO: 301). Figure 8D shows binding measurements of antibody BIIB-9-460 (VH: SEQ ID NO: 23; VL: SEQ ID NO: 213). Figure 8E shows binding measurements of antibody BIIB-9-433 (VH: SEQ ID NO: 127; VL: SEQ ID NO: 313). The plots shown show the BLI response (nm) for binding and dissociation as a function of time. [Figure 8-2] Continued from Figure 8-1. [Figure 8-3] Continued from Figure 8-2. [Figure 8-4] Continued from Figure 8-3. [Figure 8-5] Continued from Figure 8-4. [Figure 8-6] Figure 8F is a table of the apparent monovalent affinity (KD) for each of the listed antibodies (i.e., BIIB-9-484, BIIB-9-440, BIIB-9-882, BIIB-9-460, and BIIB-9-433) to (i) free FIXa or (ii) FIXa-SM (e.g., FIXa+EGR-CMK) as determined by the 1:1 fitting algorithm provided in ForteBio Data Analysis 9.0 software. [Figure 9-1] Figures 9A-9D are graphs displaying BLI binding measurements of the listed IgGs bound to the sensors of the indicated antigens: FIXn (nonactivatable FIX), free FIXa, or FXa-SM (e.g., FIXa+EGR-CMK) (all obtained from Haematologic Technologies, Inc., Essex Junction, VT, USA) as a function of time. The maximum BLI response (nm) is presented for each sensorgram. Figure 9A shows binding measurements of representative antibodies in class I (Figure 3A), e.g., antibody BIIB-9-484 and antibody BIIB-9-460 (VH: SEQ ID NO: 23; VL: SEQ ID NO: 213). Figure 9B shows binding measurements of representative antibodies in class II (Figure 3B), e.g., antibody BIIB-9-416 (VH: SEQ ID NO: 93; VL: SEQ ID NO: 279) and antibody BIIB-9-885 (VH: SEQ ID NO: 97; VL: SEQ ID NO: 283). Figure 9C shows binding measurements of a representative antibody in class III (Figure 3C), e.g., antibody BIIB-9-1287 (VH: SEQ ID NO: 181; VL: SEQ ID NO: 367). Figure 9D shows binding measurements of a representative antibody in class IV (Figure 3D), e.g., antibody BIIB-9-397 (VH: SEQ ID NO: 183; VL: SEQ ID NO: 369). [Figure 9-2] Continued from Figure 9-1. [Figure 9-3] Continued from Figure 9-2. [Figure 9-4] Continued from Figure 9-3. [Figure 10] 3 is a table showing 95 antibodies disclosed herein along with their assigned class based on antigen binding profiles as determined by BLI binding assay. Antibodies were assigned to a class if one antibody showed a difference in BLI response of 0.1 or more relative to another antibody using the assay parameters defined in this example. Class I antibodies correspond to the antibodies in FIG. 3A. Class II antibodies correspond to the antibodies in FIG. 3B. Class III antibodies correspond to the antibodies in FIG. 3C. Class IV antibodies correspond to the antibodies in FIG. 3D. [Figure 11]This table lists the wavelength maximum (nm) of each indicated antibody as determined by screening for propensity for self-interaction by AC-SINS. A threshold value of 540 nm was set based on an internal control; antibodies above the threshold are shaded in black (indicating potential self-interaction). [Figure 12-1] Figures 12A-12C are tables listing 94 antibodies disclosed herein that were discovered through antibody generation methods. The germline, CDR length, CDR amino acid sequence, and SEQ ID NO for both the VH and VL of each of the 94 antibodies are provided. The complete VH and VL sequences for each antibody are shown in Table 4. Figures 12A and 12B show antibodies that preferentially bind to FX zymogen (e.g., non-activatable FX) compared to activated clotting factor FX (FXa) (e.g., FXa covalently modified with EGR- or LTR-CMK (FXa-SM)). Figure 12C shows antibodies that preferentially bind to activated clotting factor FX (FXa) compared to FX zymogen (e.g., non-activatable FX) (e.g., FXa covalently modified with EGR- or LTR-CMK) (Class VI). [Figure 12-2] Continued from Figure 12-1. [Figure 12-3] Continued from Figure 12-2. [Figure 13A] Graph showing BLI binding measurements of sensor-bound IgG to the indicated antigens, FX zymogen, or FXa-SM (e.g., FXa+EGR-CMK). The maximal BLI response (nm) for each antibody is plotted on the y-axis. [Figure 13B] Graph showing BLI binding measurements of sensor-bound IgG to the indicated antigens, FX zymogen, or FXa-SM (e.g., FXa+EGR-CMK). The maximal BLI response (nm) for each antibody is plotted on the y-axis. [Figure 14] 1 is a table showing the apparent monovalent affinity values ​​(KD) to FX zymogen for each of the listed antibodies, M, as determined by the 1:1 fitting algorithm provided in ForteBio Data Analysis 9.0 software. [Figure 15] This table lists the wavelength maximum (nm) of each indicated antibody, as determined by screening for propensity for self-interaction by AC-SINS. A threshold value of 540 nm was set based on an internal control. Antibodies above the threshold are shaded in black, indicating potential self-interaction. [Figure 16-1] Figures 16A-16D are graphs showing 202 bispecific antibodies identified as having the ability to replace FVIIIa-like function in a chromogenic factor Xa generation assay. The 202 bispecific antibodies are divided into four groups and four corresponding subfigures. Figure 16A shows the cleavage rate of the FXa chromogenic substrate for the first group of bispecific antibodies (1-51 of 202). Figure 16B shows the cleavage rate of the FXa chromogenic substrate for the second group of bispecific antibodies (52-102 of 202). Figure 16C shows the cleavage rate of the FXa chromogenic substrate for the third group of bispecific antibodies (103-152 of 202). Figure 16D shows the cleavage rate of the FXa chromogenic substrate for the fourth group of bispecific antibodies (153-202 of 202). In each case, the average baseline rate in the absence of bispecific antibody is indicated by the dashed line. [Figure 16-2] Continued from Figure 16-1. [Figure 16-3] Continued from Figure 16-2. [Figure 16-4] Continued from Figure 16-3. [Figure 17]

[0023] Figure 1 is a graph showing the cleavage rates of the FXa chromogenic substrate for a subset of bispecific antibodies in IgG4 format. The average baseline rate in the absence of bispecific antibody is indicated by the dashed line. [Figure 18]1 is a graph illustrating the cleavage rate of a FXa chromogenic substrate in the presence of three representative bispecific antibodies. Compared to the baseline control (no antibody was added to the reaction mixture), BIIB-9-484 / BIIIB-12-915, BIIB-9-619 / BIIB-12-925, and BIIB-9-578 / BIIB-12-917 were able to increase the cleavage rate of the FXa chromogenic substrate, as indicated by an increase in OD over time. [Figure 19] 1 is a graph illustrating the ability of BIIB-9-484 / BIIB-12-917, BIIB-9-484 / BIIB-12-915 and BIIB-9-484 / BIIB-12-1306 to replace the function of FVIIIa (as indicated by a decrease in clotting time) in a one-stage clotting assay in FVIII-deficient plasma. For comparison, FVIII-deficient plasma without the bispecific antibody is shown. [Figure 20] 1 is a graph showing that the ability of the bispecific antibody BIIB-9-484 / BIIB-12-917 to replace FVIIIa function in a one-stage clotting assay with FVIII-deficient plasma depends on the bispecific format. Homodimeric BIIB-9-484, homodimeric BIIB-12-917, and a mixture of the two homodimers were unable to replace FVIIIa-like function. FVIII-deficient plasma without antibody is shown for comparison. [Figure 21] Figure 1 shows a graph depicting a BLI binding assay using a dip-and-read streptavidin biosensor to assess co-binding of each target antigen to the indicated bispecific antibodies. The sensorgram plots the BLI response (nm) as a function of time, with each experimental step separated by a vertical black line. An increase in response at a particular step indicates protein loading. [Figure 22A]The CDR sequences of BIIB-9-484 and its two affinity-matured daughters, BIIB-9-1335 and BIIB-9-1336, are listed. A CLUSTAL-format multiple sequence alignment of the VH segments of BIIB-9-484, BIIB-9-1335, and BIIB-9-1336 using MAFFT (v7.205) is presented. The degree of amino acid conservation is indicated by bars above the alignment ("*" = identical; ":" = strongly conserved; "." = poorly conserved) and below the alignment. The VH and VL CDRs are underlined. The sequence preceding VH-CDR1 is framework region (FR) 1; the sequence following VH-CDR1 and preceding VH-CDR2 is FR2; the sequence following VH-CDR2 and preceding VH-CDR3 is FR3; and the sequence following VH-CDR3 is FR4. The sequence before VL-CDR1 is framework region (FR) 1; the sequence after VL-CDR1 and before VH-CDR2 is FR2; the sequence after VL-CDR2 and before VL-CDR3 is FR3; and the sequence after VL-CDR3 is FR4. [Figure 22B] 10A-10C are graphs showing the BLI binding profiles of free FIXa to BIIB-9-484, BIIB-9-1335 and BIIB-9-1336, respectively. [Figure 22C] 10A-10C are graphs showing the BLI binding profiles of free FIXa to BIIB-9-484, BIIB-9-1335 and BIIB-9-1336, respectively. [Figure 22D] 10A-10C are graphs showing the BLI binding profiles of free FIXa to BIIB-9-484, BIIB-9-1335 and BIIB-9-1336, respectively. [Figure 23]1 is a graph showing that improved affinity of the anti-FIXa arm associated with bispecific antibodies with FVIIIa-like activity results in higher activity in a one-stage clotting assay. This example is illustrated in the top plot, where bispecific antibodies with high affinity anti-FIXa arms (BIIB-9-1335 / BIIB-12-917 and BIIB-9-1336 / BIIB-12-917) show a further reduction in clotting time compared to bispecific antibodies with low affinity anti-FIXa arms (BIIB-9-484 / BIIB-12-917). [Figure 24A] FIG. 1 shows the binding affinity of the identical bispecific antibody ("emicizumab biosimilar") emicizumab (ACE910) sequence to FIX zymogen, activated FIX, FX zymogen, and activated FX (i.e., 1 μM, 1 μM, 1 μM, and 1 μM, respectively). [Figure 24B] FIG. 1 shows the binding affinity of the bispecific molecule (BS-027125) for FIX zymogen, activated FIX, FX zymogen and activated FX (i.e., 8 nM, 2 nM, 20 nM and undetected, respectively). [Figure 25] Graph showing clotting time (seconds) for FVIII (inverted triangles), BS-025 FIXa homodimer (large diamonds), BS-027 FX homodimer (small diamonds), BS-027025 homodimer mix (triangles) and BS-027025 bispecific (squares) over a range of concentrations (IU / mL or μM). [Figure 26] 1 is a graph showing FVIII activity (% FVIII equivalents) by BS-027125 (squares), BS-027125 FIXa homodimer (triangles), and BS-027125 FX homodimer (circles). FVIII activity was measured by a one-stage clotting assay. [Figure 27]Graph showing the generation of Factor Xa (FXa) in nM by rFVIII (large circle), BS-027125 (square), BS-027125 FIXa homodimer (triangle), BS-027125 FX homodimer (inverted triangle) and BS-027125 (no PL) (small circle) as measured by a chromogenic FXa generation assay. [Figure 28A] 1 shows the results of a thrombin generation assay of BS-027125. The left panel shows the lag time (minutes) and the right panel shows the peak. [Figure 28B] Graph showing the amount of thrombin generated by rFVIII (left panel) and BS-027125 (right panel). [Figure 29] Graphs showing FXa in nM produced in the presence of rFVIII, emicizumab biosimilar, or BS-027125 using either PC / PS (80% / 20%) or PC / PE / PS (40% / 40% / 20%) phospholipid vesicles (top panel), and the fold change in activity distributed by PC / PE / PS relative to PC / PS phospholipid vesicles (bottom panel). [Figure 30] Graphs showing the results of a thrombin generation assay on PC / PE / PS phospholipids in the presence of rFVIII, emicizumab biosimilar, and BS-027125. The top panel shows lag time (min); the middle panel shows peak thrombin (nM); and the bottom panel shows endogenous thrombin potential (ETP) (nM*min). [Figure 31-1]Figures 31A, 31B, 31C, and 31D are graphs showing the epitope binning of 47 different anti-FIXa antibodies relative to each other, as determined by biolayer interferometry. Figures 31A and 31B show octaplex profiles for non-competitive and competitive binders, respectively. Figure 31C summarizes the 47 x 47 interactions tested and whether the antibody pairs result in competitive or non-competitive binding. Dark gray squares indicate cross-blocking antibody pairs, indicating that these antibodies fall into the same bin. Medium gray squares indicate non-cross-blocking antibody pairs, indicating that these antibodies fall into different bins. White squares indicate unidirectional conflicts, and light gray squares indicate antibodies for which data could not be analyzed. Figure 31D shows a nodal analysis of the binning network determined in Figure 31C. The closer two antibodies are on this map, the more similar their binning profiles become. [Figure 31-2] Continuation of Figure 31-1. [Figure 31-3] Continuation of Figure 31-2. [Figure 32] Figure 32A is a graph showing the binding profile of BIIB-9-484 to FIXa in the presence and absence of calcium using biolayer interferometry. The dashed lines indicate the end of the association phase and the beginning of the dissociation phase. Figure 32B is a graph showing the binding profile of BIIB-9-1336 to FIXa in the presence and absence of calcium using biolayer interferometry. The dashed lines indicate the end of the association phase and the beginning of the dissociation phase. [Figure 33A]Figure 1 shows the rate of substrate cleavage with FIXa (250 nM) alone or in the presence of increasing concentrations of two different anti-FIXa antibodies (BIIB-9-1336 and BIIB-9-579) or an anti-FX antibody control (BIIB-12-917). BIIB-9-1336 was tested as a bivalent antibody homodimer ("BIIB-9-1336"), as a single-arm antibody ("1-arm BIIB-9-1336"), and in a bispecific configuration with BIIB-12-917 ("BIIB-9-1336 / BIIB-12-917"). The rate of substrate cleavage is expressed in mOD / min, and antibody increments are expressed relative to the concentration (nM) of the FIXa-Ab complex. [Figure 33B] 1 is a graph showing the fold enhancement of FIXa amidolytic activity observed at 500 nM FIXa in the presence of a panel of BIIB-9-484, BIIB-9-1336, BIIB-9-619 and BIIB-9-578 antibodies. [Figure 33C] 1 is a graph showing the rate of substrate cleavage by FIXa over a range of substrate concentrations in the presence or absence of saturating amounts of BIIB-9-1336. [Figure 33D] 1 is a graph showing KM and Vmax for FIXa in the presence and absence of BIIB-9-1336. [Figure 34] Figures 34A and 34B are graphs showing the kinetics of ATIII inhibition by FIXa in the presence or absence of anti-FIXa antibodies. Figure 34A shows the appearance of a 75 kDa band corresponding to the ATIII-FIXa complex. The kinetics of complex formation, demonstrating ATIII inhibition by FIXa, is enhanced in the presence of BIIB-9-1335 and BIIB-9-1336. Figure 34B is a graph showing the band intensity of ATIII-FIXa complex formation quantified and graphed at various time points. [Figure 35] FIG. 1 is a depiction of the crystal structure of the Fab region of BIIB-9-1336 in complex with EGF2 and the serine protease domain of FIXa, shown in two orientations. [Figure 36]1 shows the serine protease domain of FIXa in a surface depiction with the epitopes of BIIB-9-1336 (1336 epitope) and FVIIIa (FVIIIa epitope) mapped to the surface. The BIIB-9-1336 epitope on FIXa and the FVIIIa epitope on FIXa are colored black. Residues shared between the two epitopes are outlined in white. [Figure 37] The specific amino acid residues in the FIXa heavy chain that make up the BIIB-9-1336 and FVIIIa epitopes and that correspond to the residues highlighted in Figure 36 are listed. Residues shared between the two epitopes are underlined and bolded. Residues shown in parentheses are not shown in Figure 36 because they do not match published reports. The numbering of amino acid residues is based on chymotrypsinogen numbering. BIIB-9-1336 also contacts one residue in the light chain of FIXa, indicated by an asterisk. The light chain contacts for FVIIIa are not listed. [Figure 38A] (B) Binding of BIIB-12-917 to a panel of FX variants, including wild-type factor X zymogen, wild-type activated FX, activated peptide, zymogen FX-depleted activated peptide, and activated FX-maintaining chimeric FIX constructs, where the FIX activated peptide was replaced by the FX activated peptide by biolayer interferometry. The dashed lines indicate the end of the association phase and the beginning of the dissociation phase. [Figure 38B] Depicts each of the above FX variants. The + and - symbols indicate whether BIIB-12-917 binds. These data indicate that the epitope for BIIB-12-917 resides in the activation peptide region of FX. DETAILED DESCRIPTION OF THE INVENTION

[0244] The present disclosure provides antibodies that preferentially bind to specific forms of coagulation factors. In particular, the present disclosure provides antibodies and antigen-binding portions thereof that specifically bind to FIX (e.g., antibodies and antigen-binding portions thereof that preferentially bind to activated factor IX (FIXa) in the presence of FIXa and factor IX zymogen (FIXz)). The present disclosure also provides antibodies and antigen-binding portions thereof that specifically and preferentially bind to FX (FX zymogen (FXz)) in the presence of FXz and FXa.

[0245] Similarly, bispecific molecules (e.g., antibodies) comprising any one of the anti-FIX antibodies, or antigen-binding portions thereof, disclosed herein and any one of the anti-FX antibodies, or antigen-binding portions thereof, disclosed herein are provided. These bispecific antibodies can simultaneously bind to FIX and FX, mimicking the function of coagulation factor VIIIa.

[0246] The disclosure also provides, for example, compositions including binding molecules, such as the antibodies disclosed herein (e.g., pharmaceutical or diagnostic compositions), nucleic acids and vectors encoding the binding molecules disclosed herein, cells comprising nucleic acids encoding the binding molecules disclosed herein, methods of making, methods of treatment and diagnosis, immunoconjugates, and kits.

[0247] The headings provided herein are not limitations of the various aspects or embodiments of the present disclosure, which can be defined by reference to the specification as a whole. Accordingly, the terms defined immediately below are fully defined herein by reference in their entirety. Before describing the present invention in detail, it is to be understood that this invention is not limited to particular compositions or method steps, as such may vary.

[0248] I. Definition In order that this disclosure may be more readily understood, certain terms are first defined. As used in this application, unless otherwise expressly set forth herein, each of the following terms shall have the meaning set forth below. Additional definitions are set forth throughout this application.

[0249] The invention includes embodiments in which exactly one member of a group is present in, used in, or otherwise relevant to a given product or process. The invention includes embodiments in which more than one or all of the members of the group are present in, used in, or otherwise relevant to a given product or process.

[0250] As used herein and in the appended claims, the singular forms "a," "an," and "the" include plural referents unless the context clearly dictates otherwise. The term "a" (or "an") and the terms "one or more," and "at least one" can be used interchangeably herein. In certain embodiments, the term "a" or "an" means "single." In other embodiments, the term "a" or "an" includes "two or more" or "plurality."

[0251] Furthermore, "and / or," when used herein, is to be considered as specifically disclosing each of the two specified features or components, with or without the other. Thus, the term "and / or" as used herein in phrases such as "A and / or B" does not necessarily mean "A and B," "A or B," It is intended to include "A" (alone) and "B" (alone). Similarly, the term "and / or" when used in phrases such as "A, B and / or C" is intended to encompass each of the following embodiments: A, B and C; A, B or C; A or C; A or B; B or C; A and C; A and B; B and C; A (alone); B (alone); and C (alone).

[0252] Unless otherwise defined, all technical terms and scientific terms used herein have the same meaning as that commonly understood by those skilled in the art to which this disclosure pertains.For example, Concise Dictionary of Biomedicine and Molecular Biology, Juo, Pei-Show, 2nd edition, 2002, CRC Press; The Dictionary of Cell and Molecular Biology, 3rd edition, 1999, Academic Press; and Oxford Dictionary of Biochemistry and Molecular Biology, Revised, 2000, Oxford University Press provide those skilled in the art with a general dictionary of many of the terms used in this disclosure.

[0253] Where an embodiment is described herein with the expression "comprising," other similar embodiments described in terms of "consisting of" and / or "consisting essentially of" are also provided.

[0254] Units, prefixes, and symbols are expressed in their accepted form in the International System of Units (SI). Numerical ranges are inclusive of the numbers defining the range. When a range of values ​​is listed, it is understood that each intervening integer and subvalue between the recited upper and lower limits of that range is also specifically disclosed, along with each subrange between such values. The upper and lower limits of any range may independently be included in or excluded from the range, and each range including one limit, neither limit, or both limits is also encompassed within the invention. When values ​​are explicitly listed, it is understood that values ​​that are approximately the same amount or the same amount as the recited value are also within the scope of the invention. When a combination is disclosed, each subcombination of the elements of that combination is also specifically disclosed and is within the scope of the invention. Conversely, when different elements or groups of elements are individually disclosed, combinations of those elements are also disclosed. Where any element of the invention is disclosed as having multiple alternatives, instances of such inventions including each alternative alone or in any combination with the other alternatives are also disclosed by this invention; more than one element of the invention may have such an exclusion, and all combinations of elements having such an exclusion are disclosed by this specification.

[0255] Nucleotides are referred to by their commonly accepted single-letter codes. Unless otherwise indicated, nucleic acids are written left to right in a 5' to 3' orientation. Nucleotides are referred to herein by their commonly known single-letter symbols recommended by the IUPAC-IUB Biochemical Nomenclature Commission. Thus, A represents adenine, C represents cytosine, G represents guanine, T represents thymine, and U represents uracil.

[0256] Amino acids are referred to herein by either their commonly known three letter symbols or by their one-letter symbols recommended by the IUPAC-IUB Biochemical Nomenclature Commission. Unless otherwise indicated, amino acid sequences are written left to right in amino to carboxy orientation.

[0257] About: The term "about," when used throughout this specification and claims in reference to numerical values, denotes an interval of precision familiar and accepted by those of ordinary skill in the art. Generally, such an interval of precision is used. The interval is ±10%.

[0258] When ranges are given, the endpoints are included. Furthermore, unless otherwise indicated or apparent from the context and the understanding of one of ordinary skill in the art, values ​​given as ranges can assume any specific value or subrange within the ranges set forth in various embodiments of the invention, down to one-tenth of the unit of the lower limit of that range, unless the context clearly dictates otherwise.

[0259] Administered in Combination: As used herein, the terms "administered in combination," "combined administration," or "combination therapy" mean that two or more agents, e.g., a binding molecule disclosed herein and a second agent, are administered to a subject simultaneously or within an interval that allows for overlap in the effects of each agent on the patient. In some embodiments, the agents are administered within about 60, 30, 15, 10, 5, or 1 minute of each other. In some embodiments, the administration of the agents is spaced sufficiently close together so that a combined (e.g., synergistic) effect is achieved.

[0260] Affinity: The term "affinity" refers to the degree to which a binding molecule, e.g., an antibody, binds to an antigen such that the equilibrium between the antigen and the binding molecule is shifted toward the presence of a complex formed by their binding. Thus, when antigen and binding molecule are combined at relatively equal concentrations, a binding molecule with a higher affinity will bind to the available antigen such that the equilibrium is shifted toward a higher concentration of the resulting complex. A binding molecule, e.g., an antibody of the present disclosure, or an antigen-binding fragment, variant, or derivative thereof, is also described or specified in terms of its binding affinity to the antigen. The affinity of a binding molecule, e.g., an antibody, for an antigen can be determined experimentally using any suitable method (e.g., Berzofsky et al., "Antibody-Antigen Interactions," In Fundamental Immunology, Paul, WE, ed., Raven Press: New York, NY (1984); Kuby, Janis, W.H. Freeman and Company, "Antibody-Antigen Interactions," in ...)). New York, NY (1992); and methods described therein).

[0261] The measured affinity of a particular binding molecule-antibody interaction can vary when measured under different conditions (e.g., salt concentration, pH). Therefore, affinity and other antigen binding parameters (e.g., K D , K. a , K. d Measurement of ) is preferably carried out using standard solutions of binding molecule and antigen, and standard buffer solutions.

[0262] "High affinity" for a binding molecule, e.g., an antibody, is at least about 1 x 10 7 liters / mole, or at least about 1 x 10 8 liters / mole, or at least about 1 x 10 9 liters / mole, or at least about 1 x 10 10 liters / mole, or at least about 1 x 10 11 liters / mole, or at least about 1 x 1012 liters / mole, or at least about 1 x 10 13 liters / mole, or at least about 1 x 10 14 liters / mole or higher equilibrium binding constant (K aff "High affinity" binding can vary with antibody isotype.

[0263] The equilibrium dissociation constant, K D is a term also used to describe antibody affinity, and K aff is the reciprocal of K D is k a k for d (i.e., k d / k a ) and expressed as molar concentration (M). D The K value can be determined using methods well established in the art. D Available methods for determining β-glucan include biolayer interferometry (BLI) assays, surface plasmon resonance, biosensor systems such as the Biacore® system, or flow cytometry. and Scatchard analysis. D is used, the term "high affinity" for an antibody refers to a -7 Less than M or about 1 x 10 -8 Less than M or about 1 x 10 -9 Less than M or about 1 x 10 -10 Less than M or about 1 x 10 -11 Less than M or about 1 x 10 -12 Less than M or about 1 x 10 13 Less than M or about 1 x 10 -14 The equilibrium dissociation constant (K D ) refers to

[0264] Amino acid substitution: The term "amino acid substitution" refers to the replacement of an amino acid residue present in a parent or reference sequence (e.g., a wild-type sequence) with another amino acid residue. The amino acid is substituted in the parent or reference sequence (e.g., a wild-type polypeptide sequence) by, for example, chemical peptide synthesis or by recombinant methods known in the art. Thus, a "substitution at position X" refers to the replacement of the amino acid present at position X with an alternative amino acid residue. In some embodiments, substitution patterns are described with reference to the schematic diagram AnY, where A is the single-letter code corresponding to the naturally or originally occurring amino acid at position n, and Y is the substituting amino acid residue. In other embodiments, substitution patterns are described with reference to the schematic diagram An(YZ), where A is the single-letter code corresponding to the amino acid residue replacing the naturally or originally occurring amino acid at position n, and Y and Z are alternative replacement amino acid residues that can replace A.

[0265] In the context of the present disclosure, substitutions (even when they are referred to as amino acid substitutions) are made at the nucleic acid level, i.e., replacement of an amino acid residue by an alternative amino acid residue is made by replacing a codon encoding a first amino acid by a codon encoding a second amino acid.

[0266] Affinity matured: The term "affinity matured" refers to a binding molecule, e.g., an antibody, that has undergone affinity maturation, a process that produces a binding molecule, e.g., an antibody, that has increased affinity for a target antigen. Thus, an affinity matured antibody is an antibody that has one or more alterations in one or more of its CDRs that result in improved affinity of the antibody for the antigen compared to a parent antibody that does not have such alterations. Exemplary affinity matured antibodies are expected to have nanomolar or even picomolar affinity for the target antigen.

[0267] In accordance with various embodiments of the invention disclosed herein, any one or more methods for producing and / or using affinity maturation libraries available in the art can be used to generate affinity matured antibodies. Exemplary affinity maturation methods include random mutagenesis, bacterial mutagen passaging, site-directed mutagenesis, mutation hotspot targeting, and minimal mutagenesis. Methods for generating and using affinity maturation libraries that include antibody shuffling, light chain shuffling, heavy chain shuffling, CDR1 and / or CDR2 mutagenesis, and that are adaptable for practicing the methods and uses according to various embodiments of the invention disclosed herein, include those disclosed in, for example, Prassler et al. (2009); Immunotherapy, Vol. 1(4), pp. 571-583; Sheedy et al. (2007), Biotechnol. Adv., Vol. 25(4), pp. 333-352; WO2012 / 009568; WO2009 / 036379; WO2010 / 105256; US2002 / 0177170; WO2003 / 074679, all of which are incorporated herein by reference in their entireties. Marks et al. (1992) BioTechnology 10:779-783 describe affinity maturation by VH and VL domain shuffling. Random mutagenesis of CDR and / or framework residues has been described by Barbas et al. (1994) Proc. Nat. Acad. Sci. USA 91:3809-3813; Schier et al. (1995) Gene 169:147-155; Yelton et al. (1995) J. Immunol. 155:1994-2004; Ja and Hawkins et al. (1992) J. Mol. Biol. 226:889-896. Mutations at selective mutagenesis positions, contact or hypermutation positions with activity-enhancing amino acid residues are described in U.S. Patent No. 6,914,128.

[0268] Animal: As used herein, the term "animal" refers to any member of the animal kingdom. In some embodiments, "animal" refers to a human at any stage of development. In some embodiments, "animal" refers to a non-human animal at any stage of development. In certain embodiments, the non-human animal is a mammal (e.g., a rodent, mouse, rat, rabbit, monkey, dog, cat, sheep, cow, primate, or pig). In some embodiments, animals include, but are not limited to, mammals, birds, reptiles, amphibians, fish, and worms. In some embodiments, the animal is a transgenic animal, a genetically engineered animal, or a clone.

[0269] Antibody: The terms "antibody" and "immunoglobulin" (abbreviated "Ig") are used interchangeably herein and refer to a molecule containing at least one immunoglobulin domain that specifically binds to or is immunologically reactive with a particular antigen. The term includes whole antibodies and any antigen-binding portions, or single chains thereof, and combinations thereof (e.g., bispecific antibodies).

[0270] A typical antibody comprises at least two heavy chains (“HC”) and two light chains (“L”) inter-connected by disulfide bonds.

[0271] Each "heavy chain" consists of a "heavy chain variable region" (abbreviated herein as "VH") and a "heavy chain constant region" (abbreviated herein as "CH"). The heavy chain constant region in an unmodified antibody consists of three constant domains, CH1, CH2, and CH3.

[0272] Each "light chain" consists of a "light chain variable region" (abbreviated herein as "VL") and a "light chain constant region." The light chain constant region in an unmodified antibody consists of one constant domain, "CL." The VH and VL regions are further subdivided into hypervariable regions called complementarity-determining regions ("CDRs"), regions dispersed with more conserved regions, and regions called "framework regions" ("FW").

[0273] Each VH and VL consists of three CDRs and four FWs, arranged from amino to carboxy terminus in the following order: FW1, CDR1, FW2, CDR2, FW3, CDR3, FW4. The present disclosure describes VH and VL sequences, as well as subsequences corresponding to CDR1, CDR2, and CDR3. Therefore, those skilled in the art will understand that the sequences FW1, FW2, FW3, and FW4 are equally disclosed. For a particular VH, FW1 is the subsequence between the N-terminus of VH and the N-terminus of VH-CDR1, FW2 is the subsequence between the C-terminus of VH-CDR1 and the N-terminus of VH-CDR2, FW3 is the subsequence between the C-terminus of VH-CDR2 and the N-terminus of VH-CDR3, and FW4 is the subsequence between the C-terminus of VH-CDR3 and the C-terminus of VH. Similarly, for a particular VL, FW1 is a subsequence between the N-terminus of VL and the N-terminus of VL-CDR1, FW2 is a subsequence between the C-terminus of VL-CDR1 and the N-terminus of VL-CDR2, FW3 is a subsequence between the C-terminus of VL-CDR2 and the N-terminus of VL-CDR3, and FW4 is a subsequence between the C-terminus of VL-CDR3 and the C-terminus of VL.

[0274] The variable regions of the heavy and light chains contain binding domains that interact with antigens. The constant regions of the antibody can mediate the binding of the immunoglobulin to host tissues or factors, including various cells of the immune system (e.g., effector cells) and the first component (C1q) of the classical complement system. Exemplary antibodies of the present disclosure include typical antibodies, scFvs, and combinations thereof. In this case, for example, the scFv is covalently linked (e.g., by a peptide bond or a chemical linker) to the N-terminus of either the heavy and / or light chain of a typical antibody, or is intercalated into the heavy and / or light chain of a typical antibody.

[0275] As used herein, the term "antibody" encompasses intact polyclonal antibodies, intact monoclonal antibodies, antibody fragments (such as Fab, Fab', F(ab')2 and Fv fragments), single-chain variable fragments (scFv), disulfide-stabilized scFv, multispecific antibodies such as bispecific antibodies generated from at least two intact antibodies and / or antigen-binding portions thereof, chimeric antibodies, humanized antibodies, human antibodies, fusion proteins comprising an antigen-determining portion of an antibody, and any other modified immunoglobulin molecule comprising an antigen-recognition site, so long as the antibody exhibits the desired biological activity.

[0276] Antibodies can be any of the five major classes of immunoglobulins (isotypes): IgA, IgD, IgE, IgG, and IgM, or subclasses thereof (e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2), based on the identity of their heavy chain constant domains, called alpha, delta, epsilon, gamma, and mu, respectively. Different classes of immunoglobulins have different and well-known subunit structures and three-dimensional configurations. Antibodies can be naked or conjugated to other molecules, such as therapeutic or diagnostic agents, to form immunoconjugates.

[0277] There are at least two techniques for determining CDRs: (1) methods based on interspecies sequence variation (i.e., Kabat et al., Sequences of Proteins of Immunological Interest (5th ed., 1991, National Institutes of Health, Bethesda, Md.), and (2) a method based on crystallographic studies of antigen-antibody complexes (Al-lazikani et al. (1997) J. Molec. Biol. 273:927-948). In addition, a combination of these two methods is sometimes used in the art to determine CDRs. The Kabat numbering system is commonly used when referring to residues in the variable domain (approximately residues 1-107 of the light chain and residues 1-113 of the heavy chain) (e.g., Kabat et al., Sequences of Immunological Interest. 5th ed., Public Health Service, National Institutes of Health, Bethesda, Md. (1991)).

[0278] The phrases "amino acid position numbering as in Kabat," "Kabat position," and grammatical variations thereof, refer to the numbering system used for the heavy or light chain variable domains of a compilation of antibodies in Kabat et al., Sequences of Proteins of Immunological Interest, 5th ed., Public Health Service, National Institutes of Health, Bethesda, Md. (1991). Using this numbering system, the actual linear amino acid sequence can contain few or additional amino acids corresponding to shortening of, or insertion into, the FW or CDRs of the variable domain. For example, a heavy chain variable domain can contain a single amino acid insertion after residue 52 of H2 (residue 52a according to Kabat) and inserted residues after heavy chain FW residue 82 (e.g., residues 82a, 82b, and 82c according to Kabat). See Table 1.

[0279] [Table 1]

[0280] The Kabat numbering of residues can be determined for a given antibody by aligning the regions of homology of the antibody sequence with the "standard" Kabat numbering sequence. Chothia instead refers to the location of the loop structure (Chothia and Lesk J. Mol. Biol. 196:901-917 (1987)). When numbered using the Kabat numbering convention, the end of the Chothia CDR-H1 loop varies between H32 and H34 depending on the length of the loop (because the Kabat numbering scheme considers insertions at H35A and H35B; if neither 35A nor 35B is present, the loop ends at 32; if only 35A is present, the loop ends at 33; and if both 35A and 35B are present, the loop ends at 34). The AbM hypervariable regions represent a compromise between the Kabat CDRs and the Chothia loop structures and are used by Oxford Molecular's AbM antibody modeling software.

[0281] IMGT (ImMunoGeneTics) also provides a numbering system for immunoglobulin variable regions, including CDRs. See, for example, Lefranc, MP et al., Dev. Comp. Immunol. 27:55-77 (2003), incorporated herein by reference. The IMGT numbering system is based on the alignment of over 5,000 sequences, structural data, and characterization of hypervariable loops, allowing for easy comparison of variable and CDR regions across all species. According to the IMGT numbering scheme, VH-CDR1 is located at positions 26-35, VH-CDR2 is located at positions 51-57, VH-CDR3 is located at positions 93-102, VL-CDR1 is located at positions 27-32, VL-CDR2 is located at positions 50-52, and VL-CDR3 is located at positions 89-97.

[0282] For all heavy chain constant region amino acid positions discussed herein, the numbering is in accordance with the EU index first described in Edelman et al., 1969, Proc. Natl. Acad. Sci. USA 63(1):78-85, which describes the amino acid sequence of the myeloma protein EU, the first human IgG to be sequenced. The EU index of Edelman et al. is based on the EU index of Kabat et al., 1991, Sequences of Proteins of Immunological Interest, 5th ed., United States Public Health Service, National Institutes of Health, Bethesda, MD. Hence the phrase "Kabat "EU index as described" or "Kabat EU index" and "position according to the EU index as described in Kabat" and grammatical variations thereof refer to the residue numbering system based on the human IgG1 EU antibody of Edelman et al. as described in Kabat 1991.

[0283] The numbering system used for variable domain (both heavy and light chain) and light chain constant region amino acid sequences is that described in Kabat 1991.

[0284] As used herein, the Fc region includes polypeptides comprising the constant region of an antibody, excluding the first constant region immunoglobulin domain. Thus, Fc refers to the last two constant region immunoglobulin domains of IgA, IgD, and IgG, and the last three constant region immunoglobulin domains of IgE and IgM, as well as the flexible hinge N-terminal to these domains. In the case of IgA and IgM, Fc can include the J chain. In the case of IgG, Fc includes the immunoglobulin domains C gamma 2 and C gamma 3 (C gamma 2 and C gamma 3), and the hinge between C gamma 1 (C gamma 1) and C gamma 2 (C gamma 2).

[0285] Although the boundaries of the Fc region can vary, the human IgG heavy chain Fc region is usually defined to include residues C226 or P230 at its carboxy terminus, where numbering is according to the EU index as set forth in Kabat. Fc can refer to such a region in isolation or in the context of an antibody, antibody fragment, or Fc fusion protein.

[0286] Polymorphisms are observed at several different positions within antibody constant regions (e.g., Fc positions, including but not limited to, positions 270, 272, 312, 315, 356, and 358, numbered according to the EU index described in Kabat), and therefore slight differences may exist between the presented sequences and those in the prior art. Polymorphisms in human immunoglobulins have been well characterized. Currently, 18 Gm allotypes are known: G1m (1, 2, 3, 17) or G1m (a, x, f, z), G2m (23) or G2m (n), G3m (5, 6, 10, 11, 13, 14, 15, 16, 21, 24, 26, 27, 28) or G3m (b1, c3, b3, b0, b3, b4, s, t, g1, c5, u, v, g5). See Lefranc et al., The human IgG subclasses: molecular analysis of structure, function and regulation. Pergamon, Oxford, pp. 43-78 (1990); Lefranc et al. (1979), Hum. Genet.: Vol. 50, pp. 199-211. It is specifically encompassed that the antibodies of the present invention can incorporate any allotype, isoallotype, or haplotype of any immunoglobulin gene, and are not limited to the allotypes, isoallotypes, or haplotypes of the sequences presented herein.

[0287] Antibody binding site: The term "antibody binding site" refers to a region on an antigen (e.g., FIXa or FXz) that contains a continuous or discontinuous site (i.e., epitope) to which a complementary antibody specifically binds. Thus, an antibody binding site can include additional regions on the antigen above the epitope that can determine properties such as binding affinity and / or stability, or that can influence properties such as antigen enzymatic activity or dimerization. Thus, even if two antibodies bind to the same epitope within an antigen, if the antibody molecules establish separate intramolecular contacts with amino acids outside the epitope, such antibodies are considered to bind to separate antibody binding sites.

[0288] Antigen-binding portion: As used herein, the term "antigen-binding portion" refers to an "antigen-binding fragment" " can be used interchangeably with " and refer to a portion of an intact antibody that is capable of specifically binding to the same epitope as the intact antibody. In particular, an antigen-binding portion refers to a portion or portions of an intact antibody that comprises one or more CDRs of the intact antibody. It is known in the art that the antigen-binding function of an antibody can be performed by fragments of a full-length antibody. Examples of antibody fragments include, but are not limited to, Fab, Fab', F(ab')2, and Fv fragments, linear antibodies, single-chain antibodies, and multispecific antibodies formed from antibody fragments.

[0289] Antigen-binding molecule: The terms "antigen-binding molecule" and "binding molecule" are used interchangeably in this disclosure and encompass antibodies, as defined herein, as well as other molecular entities that contain at least one CDR of an antibody disclosed herein and are capable of binding to the same epitope. For example, the term includes pseudoantibodies based on fibronectin type III (monobody) scaffolds, other scaffold systems (e.g., tennessine) onto which one or more CDRs are grafted, aptamers, etc. In some embodiments, antibody-binding molecules can be bispecific, i.e., "bispecific binding molecules" or "bispecific molecules."

[0290] About: As used herein, the term "about," when applied to one or more values ​​of interest, refers to a value similar to a stated reference value. In certain embodiments, the term "about" refers to a range of values ​​that fall within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1% or less in either direction (greater or less than the stated reference value) of the stated reference value, unless otherwise stated or otherwise apparent from the context (except where such number exceeds 100% of possible values).

[0291] Associated: As used herein in reference to a disease, the term "associated" means that the symptom, measurement, characteristic, or condition in question is linked to the diagnosis, onset, presence, or progression of the disease. Associated may, but need not, be causally linked to the disease.

[0292] The terms "associated," "conjugated," "linked," "attached," and "tethered," when used in reference to two or more moieties, mean that the moieties are physically attached or linked to one another, either directly or through one or more additional moieties that act as cross-linkers, to form a sufficiently stable structure so that the moieties remain physically attached under the conditions in which the structure is used, e.g., physiological conditions. "Attachment" need not be strictly by direct covalent chemical bonding. "Attachment" may also imply a sufficiently stable ionic or hydrogen bond, or hybridization-based bond, so that the "attached" entities remain physically attached.

[0293] Binding affinity: "Binding affinity" generally refers to the strength of the sum of non-covalent interactions between a single binding site of a molecule (e.g., an antibody) and its binding partner (e.g., an antigen). Unless otherwise indicated, as used herein, "binding affinity" refers to the potential binding affinity that reflects a 1:1 interaction between members of a binding pair (e.g., an antibody and an antigen). The affinity of a molecule X for its partner Y is determined by the dissociation constant (K D) Affinity can be generally expressed by the following formula: Affinity can be measured by general methods known in the art, including the methods described herein. Low-affinity antibodies generally bind to antigens slowly and tend to dissociate easily, while high-affinity antibodies generally tend to bind more quickly and maintain binding for longer. Various methods for measuring binding affinity are known in the art, any of which can be used for the purposes of the present disclosure.

[0294] The terms "higher binding affinity" or "greater affinity," when applied to any of the antibodies of the invention, refer to an increase in binding affinity (e.g., K D In some embodiments, the reference antibody refers to a corresponding antibody that has not been affinity matured. In some embodiments, the reference antibody is another antibody having the same specificity (e.g., in the case of an anti-FIXa antibody disclosed herein, the reference antibody can be another anti-FIX or anti-FIXa antibody known in the art). In some embodiments, the increase in binding affinity can be, for example, at least about 10%, at least about 20%, at least about 30%, at least about 40%, at least about 50%, at least about 60%, at least about 70%, at least about 80%, at least about 90%, or at least about 100% greater than the binding affinity of the reference antibody for the same coagulation factor (e.g., FIX or FX), form of the factor (e.g., FIXa or FXz), or antigen-binding site (e.g., epitope). In some embodiments, the increased binding affinity can be, for example, at least about 2-fold, at least about 3-fold, at least about 4-fold, at least about 5-fold, at least about 6-fold, at least about 7-fold, at least about 8-fold, at least about 9-fold, or at least about 10-fold greater than the binding affinity of a reference antibody for the same coagulation factor (e.g., FIX or FX), form of the factor (e.g., FIXa or FXz), or antigen-binding site (e.g., epitope).

[0295] Binding: The term "binding" refers to the physical interaction between two molecules, for example, an antibody and an antigen. (i) Binding specificity: The term "specificity" refers to the ability of a binding molecule, e.g., an antibody, to preferentially bind to one antigenic site (e.g., epitope) over a variety of antigenic sites and does not necessarily imply high affinity. The terms "binding specificity" and "specificity" are used interchangeably and can refer to both (i) a particular portion of a binding molecule and (ii) the ability of a binding molecule to specifically bind to a particular epitope (see the definition of "specific binding" below). For example, in some embodiments, a bispecific antibody disclosed herein comprises two binding specificities, i.e., a first binding specificity, e.g., to FIXa, and a second binding specificity, e.g., to FXz (in this context, "binding specificity," e.g., the specific region of a bispecific antibody binding to a particular antigenic determinant, is equivalent to "binding domain"). (ii) Specific binding: A binding molecule, e.g., an antibody, "specifically binds" when there is an immunological reaction of specific interaction between an antigen and the binding molecule. The term "specifically binds" means that an antibody is generated and binds to an antigen via its variable region. The term "non-specific binding" means that an antibody is not generated to specifically bind to an antigen, but may bind to some antigen via non-specific means. As an example, an antibody is expected to non-specifically bind to an Fc receptor via the Fc portion of the antibody molecule. As another example, certain antibodies may incorrectly cross-react with antigens for which they are not generated. (iii) Preferential Binding: A binding molecule, e.g., an antibody, "preferentially binds" to an antigen if it binds with greater affinity, avidity, more readily, and / or for a longer duration than it binds to other substances. For example, antibodies that preferentially bind to a FIXa epitope are antibodies that bind to this epitope with greater affinity, avidity, more readily, and / or for a longer duration than they bind to other FIXa epitopes or non-FIXa epitopes. For example, if more than 50%, 60%, 70%, 80%, 90%, or 95% of an anti-FIX antibody binds to FIXa in the presence of both FIXa and FIXz, the anti-FIX antibody preferentially binds activated FIX over FIX zymogen. For example, it is also understood by reading this definition that an antibody (or moiety or epitope) that preferentially binds to a first target may or may not preferentially bind to a second target. Thus, "preferential binding" does not necessarily require (but can include) exclusive binding. Thus, in some embodiments, "preferential binding" can be "exclusive binding." To illustrate these concepts, if 50% of anti-FIX specifically binds to FIX zymogen and 50% specifically binds to FIXa, such binding is "non-selective" or "non-preferential." If less than 50% of anti-FIX binds to FIX zymogen and more than 50% binds to FXa, the anti-FIX "preferentially binds" to FIXa. If anti-FIX: An anti-FIX "binds exclusively" to FIXa if it does not bind to FIX zymogen and only binds to FIXa.

[0296] Biological sample: As used herein, the term "biological sample" refers to any sample obtained from a subject, cell line, tissue culture, or other source potentially containing molecules, including antigens specifically recognized by the binding molecules disclosed herein. In some embodiments, the biological sample is a blood sample or a sample derived from a blood sample (e.g., plasma). Methods for obtaining tissue biopsies and body fluids from mammals are well known in the art.

[0297] Bispecific antibody: A "bispecific antibody" is a specific type of "bispecific molecule" or "bispecific binding molecule." The term "bispecific antibody" refers to an antibody that can bind to at least two antigenic determinants (e.g., epitopes) through two different antigen-binding sites. In certain embodiments, a bispecific antibody can simultaneously bind to two antigenic determinants (e.g., epitopes). In some embodiments, a bispecific antibody binds to one antigen (epitope) on one of its binding arms (a pair of heavy / light chains) and to a different antigen (or epitope) on its second binding arm (a different pair of heavy / light chains). In some embodiments, a bispecific antibody can have two separate antigen-binding arms (in both specificity and CDR sequences) and be monovalent for each antigen to which it binds. Bispecific antibodies include, for example, those generated by quadroma technology (Milstein and Cuello (1983) Nature 305(5934):537-40), by chemical conjugation of two different monoclonal antibodies (Staerz et al. (1985) Nature 314(6012):628-31), or by knob-into-hole or similar techniques for introducing mutations into the Fc region (Holliger et al. (1993) Proc. Natl. Acad. Sci. USA 90(14):6444-6448).

[0298] A wide range of recombinant bispecific antibody formats has been developed in the last decade, for example by fusion of IgG antibody formats and single chain domains (see Kontermann RE, mAbs 4:2 (2012) 1-16). Bispecific antibodies in which the variable domains VL and VH, or the constant domains CL and CH1, are replaced by each other are described in WO2009080251 and WO2009080252.

[0299] A technique known as "knobs-into-holes" to circumvent the problem of mispairing by-products aims to force pairing of two different antibody heavy chains by modifying the contact boundary by introducing mutations into the CH3 domain. Bulky amino acids were replaced on one chain with amino acids with short side chains to create "holes." Conversely, amino acids with large side chains were introduced into the other CH3 domain to create "knobs." By co-expressing these two heavy chains (and two identical light chains that must be compatible with both heavy chains), higher yields of heterodimerization ("knobs-holes") were observed compared to homodimerization ("hole-holes" or "knobs-knobs") (Ridgway JB, Presta LG, Carter P; and WO1996027011). The rate of heterodimerization can be further increased by remodeling the interaction surfaces of the two CH3 domains using phage display techniques and introducing disulfide bridges to stabilize the heterodimers (Merchant AM et al., Nature Biotech 16 (1998) 677-681; Atwell S, Ridgway JB, Wells JA, Carter P., J Mol Biol 270 (1997) 26-35). The method is described, for example, in EP1870459A1, Xie, Z. et al., J Immunol Methods 286 (2005) 95-101, and refers to a bispecific antibody format that uses scFvs in combination with knob-into-hole technology for the Fc portion.

[0300] The modular structure of antibodies has been exploited to generate over 60 different bispecific antibody formats, see Spiess et al. (2015) Molecular Immunology 67:95-106, which is incorporated herein by reference in its entirety. Thus, in some embodiments, bispecific antibody formats include crossMab, DAF (dual acting Fab) (two-in-one), DAF (four-in-one), DutaMab, DT-IgG, knob-in-hole common LC, knob-in-hole assembly, charge pair, Fab-arm exchange, SEED body, Triomab, LUZ-Y (a leucine zipper containing bispecific antibody, including heterodimerization of two HCs), Fcab, Kλ-body, orthogonal Fab, DVD-IgG (dual variable domain IgG), IgG(H)-scFv, scFv-(H)IgG, IgG(L)-scFv, scFv-(L)IgG, IgG(L,H)-Fv, IgG(H)-V, V(H)-IgG, IgG(L)-V, V(L)-IgG, KIH IgG-scFab, 2scFv-IgG, IgG-2scFv, scFv4-Ig, Zybody, DVI-IgG (four-in-one), nanobody, nanobody-HSA, BiTE (bispecific T cell engager), diabody, DART (dual affinity retargeting), TandAb (tandem antibody), sc diabody, sc diabody-CH3, triple body, minibody, minibody, TriBi minibody, scFv-CH3 KIH, Fab-scFv, scFv-CH-CL-scFv, F(ab')2, F(ab')2-ScFv2, scFv-KIH, Fab-scFv-Fc, tetravalent HC Selected from Ab, sc diabody-Fc, diabody-Fc, tandem scFv-Fc, intrabody, dock and lock, ImmTAC, HSA body, sc diabody-HSA, tandem scFv-toxin, IgG-IgG, Cov-X-body and scFv1-PEG-scFV2.

[0301] In some embodiments, the bispecific antibody is an asymmetric (e.g., heterodimeric) antibody comprising chain A and chain B, (i) Chain A contains the T336W mutation and chain B contains the T366W, L368A, and Y407V mutations (knobs-in-hole format); (ii) Chain A contains the F405L mutation and chain B contains the K409R mutation (duobody format); (iii) chain A contains T350V, L351Y, F405A, and Y407V mutations, and chain B contains T350V, T366L, K392L, and T394W mutations (azymetric format); (iv) Chain A contains K409D and K392D mutations and chain B contains D399K and E356K mutations (charge-pair format); (v) Chain A contains D221E, P228E, and L368E mutations, and chain B contains D221R, P228R, and K409R mutations (charge-pair format); (vi) chain A contains S364H and F405A mutations and chain B contains Y349T and T394F mutations (HA-TF format); or (vii) Chain A comprises an IgG / A chimera and chain B also comprises an IgG / A chimera (SEED body format).

[0302] In some embodiments, bispecific antibodies are monospecific antibodies that have been engineered to be bispecific by adding either the amino or carboxy terminus of either the light or heavy chain with an additional antigen-binding unit. Alternatives to these additional antigen-binding units include single domain antibodies (unpaired VL or VH), paired antibody variable domains (e.g., Fv or scFv) or engineered protein scaffolds. In some embodiments, bispecific molecules of the invention comprise bispecific antibody fragments. Numerous bispecific fragment forms that lack some or all of the bispecific antibody constant domains are known in the art. In some embodiments, bispecific molecules of the invention are bispecific fusion proteins, e.g., ImmTAC (scFv linked to an affinity matured receptor). In other embodiments, bispecific molecules are bispecific antibody conjugates.

[0303] Bispecific molecule: See definition of "antigen-binding molecule" / "binding molecule" above.

[0304] Chimeric antibody: The term "chimeric" antibody and grammatical variations thereof refer to antibodies in which the amino acid sequences of the immunoglobulin molecules are derived from two or more animal species. Typically, the variable regions of both the light and heavy chains correspond to the variable regions of antibodies derived from one species of mammal (e.g., mouse, rat, rabbit, etc.) having the desired specificity, and / or affinity, and / or capacity, while the constant regions are homologous to sequences in antibodies derived from another species (usually human) to avoid eliciting an immune response in that species.

[0305] Complementarity determining region: The term "complementarity determining region" or "CDR" refers to the variable region of either the H (heavy) or L (light) chain that contains the amino acid sequences capable of specifically binding to an antigen target. These CDR regions are responsible for the basic specificity of the antibody with respect to the structure of a particular antigenic determinant. Such regions are also called "hypervariable regions." See the definition of "antibody" above.

[0306] Conservative amino acid substitution: "Conservative amino acid substitution" refers to an amino acid residue that is replaced with an amino acid residue that has a similar side chain. Families of amino acid residues with similar side chains have been defined in the art, and include basic side chains (e.g., lysine, arginine, or histidine), acidic side chains (e.g., aspartic acid or glutamic acid), uncharged polar side chains (e.g., glycine, asparagine, glutamine, serine, threonine, tyrosine, or cysteine), nonpolar side chains (e.g., alanine, valine, leucine, isoleucine, proline, phenylalanine, methionine, or tryptophan), beta-branched side chains (e.g., threonine, valine, isoleucine), and aromatic side chains (e.g., tyrosine, phenylalanine, tryptophan, or histidine). Thus, if an amino acid in a polypeptide is replaced with another amino acid from the same side chain family, the amino acid substitution is considered conservative. In another embodiment, amino acid stretches are conservatively replaced with structurally similar stretches that differ in the order and / or composition of side chain family members.

[0307] Non-conservative amino acid substitutions include (i) replacing a residue having an electropositive side chain (e.g., Arg, His, or Lys) with or by an electronegative side chain (e.g., Glu or Asp); (ii) replacing a hydrophilic residue (e.g., Ser or Thr) with or by a hydrophobic residue (e.g., Ala, Leu, Ile, Phe, or Val); (iii) replacing a cysteine ​​or proline with or by any other residue; or (iv) replacing a residue having a bulky hydrophobic or aromatic side chain (e.g., Val, His, Ile, or Trp) with or by a small side chain (e.g., Ala or Ser) or no side chain (e.g., Gly).

[0308] Other amino acid substitutions are readily identified by those skilled in the art. For example, for the amino acid alanine, substitutions can be taken from any one of D-alanine, glycine, beta-alanine, L-cysteine, and D-cysteine. For lysine, substitutions can be taken from any one of D-lysine, arginine, D-arginine, homo-arginine, methionine, D-methionine, ornithine, or or D-ornithine. Generally, substitutions in functionally important regions that are expected to induce changes in the properties of the isolated polypeptide include: (i) polar residues, such as serine or threonine, replaced with (or by) hydrophobic residues, such as leucine, isoleucine, phenylalanine, or alanine; (ii) cysteine ​​residues replaced with (or by) any other residue; (iii) residues with electropositive side chains, such as lysine, arginine, or histidine, replaced with (or by) residues with electronegative side chains, such as glutamic acid or aspartic acid; or (iv) residues with bulky side chains, such as phenylalanine, replaced with (or by) those without such side chains, such as glycine. The likelihood that one of the above non-conservative substitutions can alter the functional properties of a protein also depends on the substitution location with respect to the functionally important regions of the protein; therefore, some non-conservative substitutions may have little or no effect on biological properties.

[0309] Conserved: As used herein, the term "conserved" refers to nucleotide or amino acid residues of a polynucleotide or polypeptide sequence, respectively, that are not altered in the same position in two or more sequences being compared. Relatively, a conserved nucleotide or amino acid is one that is conserved among more related sequences than a nucleotide or amino acid that appears elsewhere in the sequence.

[0310] In some embodiments, two or more sequences can be said to be "fully conserved" or "identical" if they are 100% identical to each other. In some embodiments, two or more sequences are said to be "highly conserved" if they are at least 70% identical, at least 80% identical, at least 90% identical, or at least 95% identical to each other. In some embodiments, two or more sequences are said to be "highly conserved" if they are about 70% identical, about 80% identical, about 90% identical, about 95%, about 98%, or about 99% identical to each other. In some embodiments, two or more sequences are said to be "conserved" if they are at least 30% identical, at least 40% identical, at least 50% identical, at least 60% identical, at least 70% identical, at least 80% identical, at least 90% identical, or at least 95% identical to each other. In some embodiments, two or more sequences are said to be "conserved" if they are about 30% identical, about 40% identical, about 50% identical, about 60% identical, about 70% identical, about 80% identical, about 90% identical, about 95% identical, about 98% identical, or about 99% identical to one another. Sequence conservation can apply to the entire length of a polynucleotide or polypeptide, or to portions, regions, or features thereof.

[0311] Cross-compete: The terms "compete" or "cross-compete," as used herein with respect to binding molecules, e.g., antibodies, mean that a first binding molecule, e.g., a first antibody or antigen-binding portion thereof, binds to an epitope sufficiently similar to the binding of a second binding molecule, e.g., a second antibody or antigen-binding portion thereof, such that binding of the first binding molecule to its cognate epitope is detectably reduced in the presence of the second binding molecule compared to binding of the first binding molecule in the absence of the second binding molecule. Alternatively, the binding of the second binding molecule to its epitope may, but need not, be detectably reduced in the presence of the first binding molecule. That is, a first binding molecule can inhibit binding of a second binding molecule to its epitope without the second molecule inhibiting binding of the first binding molecule to its respective epitope. However, if each binding molecule detectably inhibits binding of the other binding molecule bearing its cognate epitope, whether to the same extent, a greater extent, or a lesser extent, the binding molecules are said to "cross-compete" with each other for their respective epitopes. Both competitive and cross-competitive binding molecules are encompassed by the present invention.

[0312] Binding molecules, e.g., antibodies, are said to "bind to the same epitope" or "comprise the same binding site" or have "substantially the same binding" characteristics if they cross-compete, such that only one antibody can bind to an epitope at a given time, i.e., one binding molecule inhibits binding of or modulates the effect of the other molecule.

[0313] Competition herein refers to at least about 20%, at least about 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, or greater than about 100% relative inhibition as determined by competitive ELISA analysis or, for example, by ForteBio analysis as described in the Examples section. In certain contexts, it may be desirable to establish a higher threshold of relative inhibition as a diagnostic criterion for a suitable level of competition. Thus, for example, it is possible to set diagnostic criteria for competitive binding such that a relative inhibition of at least about 40%, or at least about 45%, or at least about 50%, or at least about 55%, or at least about 60%, or at least about 65%, or at least about 70%, or at least about 75%, or at least about 80%, or at least about 85%, or at least about 90%, or at least about 95%, or even about 100%, is detected before an antibody is considered sufficiently competitive.

[0314] Effective amount: As used herein, the term "effective amount" of an agent, e.g., a therapeutic agent such as an antibody, is such an amount sufficient to produce a beneficial or desired result, e.g., a clinical result; therefore, "effective amount" depends on the context in which it is applied. For example, in the context of administering a therapeutic agent to treat bleeding, an effective amount of the agent is an amount sufficient to reduce or decrease the incidence of bleeding, e.g., compared to the response obtained when the agent is not administered. The term "effective amount" can be used interchangeably with "effective dose," "therapeutically effective amount," or "therapeutically effective dose."

[0315] Effector function: The "effector function" of an antibody is its ability to bind to complement proteins, which can assist in lysing target antigens, such as cellular pathogens, in a process called complement-dependent cytotoxicity (CDC). Another effector activity of the Fc region is binding to Fc receptors (e.g., FcγR) on the surface of immune cells, so-called effector cells, which have the ability to trigger other immunological effects. The effector function of an antibody can be avoided, for example, by using an antibody fragment without an Fc region (e.g., Fab, F(ab')2, or single-chain Fv (scFv)), by removing sugars linked to specific residues in the Fc region (aglycosylated antibodies), or by using an Fc region derived from an IgG4 antibody ("effector-less IgG4 Fc") instead of an IgG1. It is well known that IgG4 antibodies are characterized by lower levels of complement activation and antibody-dependent cellular cytotoxicity than IgG1.

[0316] Engineered antibody: As used herein, embodiments of the present invention are "engineered" if they are designed to have characteristics or properties, whether structural or chemical, that are altered from the starting, wild-type, or naturally occurring molecule. In this regard, "engineered antibodies" are antibodies that have, for example, been modified by substitution / mutation to improve affinity, plasma half-life, etc., the format of these antibodies has been modified (e.g., by generating scFvs or bispecific antibodies), or the antibodies have been subjected to affinity maturation.

[0317] Epitope: As used herein, the term "epitope" refers to an antigenic protein determinant (e.g., an amino acid subsequence of FIXa or FXz) capable of binding to a binding molecule, e.g., an antibody. Epitopes usually consist of chemically active surface groups of molecules, such as amino acids or sugar side chains, and usually have specific three-dimensional structural and charge characteristics. The portion of an antibody or binding molecule that recognizes an epitope is called a paratope. Epitopes of protein antigens are divided into two categories based on their structure and interaction with the paratope: conformational epitopes and linear epitopes. Conformational epitopes consist of discontinuous stretches of the antigen's amino acid sequence. These epitopes interact with paratopes based on the 3D surface features and shape, or tertiary structure, of the antigen. In contrast, linear epitopes interact with paratopes based on their primary structure. Linear epitopes are formed by a continuous sequence of amino acids derived from the antigen.

[0318] Expression Vector: An "expression vector" is a polynucleotide that is transcribed and translated into a polypeptide when introduced into an appropriate host. An "expression system" generally refers to a suitable host cell comprising an expression vector that can function to yield a desired expression product. Antibodies (e.g., bispecific antibodies) according to the present invention are preferably produced by recombinant means. Such methods are widely known in the state of the art and involve expression of proteins in prokaryotic and eukaryotic cells, with subsequent isolation of the antibody polypeptide, and purification, usually to a pharmaceutically acceptable degree of purity.

[0319] Germline sequence: As used herein, the term "germline sequence" refers to the sequence of an unrearranged immunoglobulin DNA sequence. Any suitable source of unrearranged immunoglobulin can be used. The term "germline" refers to the sequence of the V, D, and J minigenes prior to exposure of the antibody to antigen. A rearranged "V region" describes the genetic elements resulting from a rearrangement event between the V, D, and J (for heavy chains) or V and J minigenes (for light chains). An "antibody V region" refers to the polypeptide region encoded by the V, D, and J elements. An "antibody V region" is encoded by rearranged V, D, and J minigenes. The term "V(D)J recombination" refers to any method in which a V, D, or J minigene is recombined with another V, D, or J minigene. The V region can be part of a full-length antibody, a Fab, an scFv, or any other derivative of an antibody (see antibody definition below). "Germline V region" refers to the rearranged V, D, and J minigene sequence prior to any significant mutational events. Germline V regions may have random insertions or deletions at the VD, DJ, or VJ minigene junctions. Non-germline V regions (or "mature" V regions) typically differ from the germline sequence of the minigene by more than 5 residues (not including junction deletions or insertions).

[0320] Homology: As used herein, the term "homology" refers to the overall relatedness between polymer molecules, such as nucleic acid molecules (e.g., DNA molecules and / or RNA molecules) and / or polypeptide molecules. Generally, the term "homology" implies an evolutionary relationship between two molecules. Thus, two molecules that are homologous are expected to share a common evolutionary ancestor. In the context of the present invention, the term homology encompasses both identity and similarity.

[0321] In some embodiments, polymer molecules are considered "homologous" to one another if at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% of the monomers in the molecules are identical (exactly the same monomers) or similar (conservative substitutions). The term "homologous" necessarily refers to a comparison between at least two sequences (polynucleotide or polypeptide sequences).

[0322] Human antibody: The term "human antibody" refers to an antibody produced by a human or an antibody known in the art. "human antibody" refers to an antibody having an amino acid sequence corresponding to an antibody produced by a human, produced using any known technique (e.g., recombinant expression in cultured cells or expression in transgenic animals). Thus, the term human antibody also encompasses antibodies (or engineered variants or derivatives thereof) having an amino acid sequence corresponding to an antibody originally produced by a human but expressed in a non-human system (e.g., produced by chemical synthesis; recombinantly expressed in bacterial, mammalian, or insect cells; or expressed in an animal subject). Thus, an antibody obtained from a human subject or from a human cell (e.g., a hybridoma, or a cell line expressing a recombinant antibody or fragment thereof) and subsequently expressed in an animal, e.g., a mouse, is considered a human antibody. This definition of human antibody includes intact or full-length antibodies, fragments thereof, and / or antibodies comprising at least one human heavy and / or light chain polypeptide, e.g., an antibody comprising a mouse light chain and a human heavy chain peptide.

[0323] Humanized antibody: The term "humanized antibody" refers to an antibody derived from a non-human (e.g., murine) immunoglobulin that has been engineered to contain minimal non-human (e.g., murine) sequences. Typically, humanized antibodies are human immunoglobulins in which residues from the CDRs are replaced by residues from the CDRs of a non-human species (e.g., mouse, rat, rabbit, or hamster) having the desired specificity, affinity, and capacity (Jones et al., 1986, Nature, 321:522-525; Riechmann et al., 1988, Nature, 332:323-327; Verhoeyen et al., 1988, Science, 239:1534-1536). In some instances, FW residues of a human immunoglobulin are replaced by the corresponding residues in an antibody derived from a non-human species having the desired specificity, affinity, and / or capacity.

[0324] Humanized antibodies can be further modified by substituting additional residues either in the FW region and / or within the replaced non-human residues to define and optimize antibody specificity, affinity, and / or potency. Generally, a humanized antibody comprises substantially all of at least one, and usually two or three, variable domains containing all or substantially all of the CDR regions corresponding to a non-human immunoglobulin, while all or substantially all of the FW region are of a human immunoglobulin consensus sequence. A humanized antibody can also comprise at least a portion of an immunoglobulin constant region or domain (Fc), typically that of a human immunoglobulin. Examples of methods used to generate humanized antibodies are described in U.S. Patent Nos. 5,225,539 or 5,639,641.

[0325] Identity: As used herein, the term "identity" refers to the overall conservation of monomers between polymer molecules, e.g., polypeptide molecules or polynucleotide molecules (e.g., DNA molecules and / or RNA molecules). For example, the term "identical" protein A without any additional modifiers is identical to protein B, meaning that the sequences are 100% identical (100% sequence identity). When two sequences are described as, for example, "70% identical," it is the same as describing them as having, for example, "70% sequence identity."

[0326] Calculation of the percent identity of two polynucleotide sequences can be performed, for example, by aligning the two sequences for optimal comparison purposes (e.g., gaps are introduced into one or both of the first and second nucleic acid sequences for optimal alignment, and non-identical sequences are ignored for comparison purposes). In certain embodiments, the length of the sequence aligned for comparison purposes is at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or 100% of the length of the reference sequence. Nucleotides at corresponding nucleotide positions are then compared. Positions in the first sequence are compared to corresponding positions in the second sequence. If a position is occupied by the same nucleotide as the position at which the sequence is located, the molecules are identical. The percent identity between two sequences correlates with the number of identical positions the sequences share, taking into account the number of gaps and the length of each gap that need to be introduced for optimal alignment of the two sequences. Sequence comparison and determination of percent identity between two sequences can be performed using a mathematical algorithm. When comparing DNA and RNA, thymine (T) and uracil (U) can be considered equivalent.

[0327] Suitable software programs for aligning both protein and nucleotide sequences are available from a variety of sources. One suitable program for determining percent sequence identity is bl2seq, part of the BLAST suite of programs available from the National Center for Biotechnology Information BLAST website (blast.ncbi.nlm.nih.gov). bl2seq performs comparisons between two sequences using either the BLASTN or BLASTP algorithm. BLASTN is used to compare nucleic acid sequences, while BLASTP is used to compare amino acid sequences. Other suitable programs are, for example, Needle, Stretcher, Water, or Matcher, part of the EMBOSS suite of bioinformatics programs, also available from the European Bioinformatics Institute (EBI) at www.ebi.ac.uk / Tools / psa.

[0328] Sequence alignment can be performed using methods known in the art, such as MAFFT, Clustal (Clustal W, Clustal X, or Clustal Omega), and MUSCLE.

[0329] Different regions in a single polynucleotide or polypeptide target sequence that aligns with a polynucleotide or polypeptide reference sequence can each have their own sequence identity percentage.It is noted that the sequence identity percentage value is rounded to two decimal places.For example, 80.11, 80.12, 80.13 and 80.14 are rounded down to 80.1, while 80.15, 80.16, 80.17, 80.18 and 80.19 are rounded up to 80.2.It is also noted that the length value is always an integer.

[0330] In certain embodiments, the percent identity (%ID) of a first amino acid sequence (or nucleic acid sequence) to a second amino acid sequence (or nucleic acid sequence) is calculated as %ID=100×(Y / Z), where Y is the number of amino acid residues (or nucleic acid bases) scored as identity matches in an alignment of the first and second sequences (aligned by visual inspection or a particular sequence alignment program), and Z is the total number of residues in the second sequence. If the length of the first sequence is longer than the second sequence, the percent identity of the first sequence to the second sequence will be higher than the percent identity of the second sequence to the first sequence.

[0331] Those skilled in the art will understand that the generation of sequence alignments for calculating percent sequence identity is not limited to binary sequence-sequence comparisons driven solely by primary sequence data. It will also be understood that sequence alignments can be generated by integrating sequence data with data from heterogeneous sources, such as structural data (e.g., protein crystal structures), functional data (e.g., mutation locations), or phylogenetic data. A suitable program for integrating heterogeneous data to generate multiple sequence alignments is T-Coffee, available at www.tcoffee.org, and alternatively, for example, from EBI. It will also be understood that the final alignment used to calculate percent sequence identity can be curated either automatically or manually.

[0332] Immunoconjugate: The term "immunoconjugate," as used herein, refers to a Immunoconjugates refer to compounds comprising a binding molecule (e.g., anti-FIXa, anti-FXz, or biospecific anti-FIXa / anti-FXz) and one or more moieties, e.g., therapeutic or diagnostic moieties, chemically conjugated to the binding molecule. Generally, immunoconjugates are defined by the general formula: A-(LM)n, where A is the binding molecule (e.g., an antibody), L is an optional linker, M is a heterologous moiety, which may be, e.g., a therapeutic agent, a detectable label, etc., and n is an integer. Immunoconjugates can also be defined by the general formula in the reverse order. In some embodiments, an immunoconjugate is an "antibody-drug conjugate" ("ADC"). In the context of the present disclosure, the term "immunoconjugate" is not limited to chemically or enzymatically conjugated molecules. The term "immunoconjugate" as used in this disclosure also includes genetic fusions.

[0333] Isolated: As used herein, the term "isolated" refers to a substance or entity (e.g., a polypeptide, antibody, polynucleotide, vector, cell, or composition in a form not found in nature) that has been separated from at least some of the components with which it is associated (whether in nature or in an experimental setting). Isolated substances (e.g., nucleotide sequences or protein sequences) can have various levels of purity with reference to the materials to which they are associated.

[0334] Isolated substances and / or entities are separated from at least about 10%, at least about 15%, at least about 20%, at least 25%, at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least 95% or more of other components with which they are initially associated.

[0335] In some embodiments, the isolated agent is greater than about 80%, about 85%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or greater than about 99% pure.

[0336] As used herein, a substance is "pure" if it is substantially free of other components. The term "substantially isolated" means that the compound is substantially separated from the environment in which it was formed or detected. Partial separation can include, for example, compositions enriched in a compound of the present disclosure. Substantial separation can include compositions containing at least about 30%, at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at least about 65%, at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 97%, or at least about 99% by weight of a compound of the present disclosure or a salt thereof.

[0337] An "isolated" polynucleotide (e.g., antibody), vector, polypeptide, cell, or any composition disclosed herein is a polynucleotide (e.g., antibody), vector, polypeptide, cell, or composition that is in a form not found in nature. Isolated polynucleotides, vectors, polypeptides, or compositions include those that have been purified to the extent that they are no longer in the form found in nature. In some embodiments, an isolated polynucleotide, vector, polypeptide, or composition is substantially pure.

[0338] Mimicking FVIIIa activity: The ability of the binding molecules disclosed herein to "mimic FVIIIa activity," i.e., to mimic the activity of activated Factor VIII, can be measured by a variety of methods known in the art. One such method is the The chromogenic assay is described in the Examples section of the specification. In one embodiment, a binding molecule (e.g., a bispecific antibody) disclosed herein is said to "mimic FVIIIa activity" if the observed rate of FXa substrate cleavage is at least three standard deviations higher than the mean basal rate in the absence of added binding molecule (e.g., a bispecific antibody). Another exemplary method is the activated partial thromboplastin time (aPTT) assay. The term "activated partial thromboplastin time (APTT)" derives from the original form of the test (devised in 1953) in which only the phospholipid concentration of the test was controlled (as opposed to the phospholipid and surface activator concentrations), and the name "partial thromboplastin" applied to the time to phospholipid preparation, which accelerates clotting but does not correct for the prolonged clotting time of hemophilic plasma. Essentially, the term "partial" means that phospholipid is present but tissue factor is not. The aPTT is also known as the kaolin cephalin clotting time (KCCT) or the kaolin-added partial thromboplastin time (PTTK). Other useful methods include the one-stage (OS) clotting assay, which is modified from the traditional aPTT assay described above. The one-stage clotting assay uses FVIII-deficient plasma and a diluted test sample and can be quantitative for FVIII activity. See Example 4. In contrast, the aPTT assay uses an aPTT reagent and sample plasma containing calcium and reports the clotting time.

[0339] Monoclonal antibody: A "monoclonal antibody" refers to a homogeneous antibody population responsible for highly specific recognition and binding of a single antigenic determinant or epitope. This is in contrast to polyclonal antibodies, which typically contain different antibodies directed against different antigenic determinants. The term "monoclonal antibody" encompasses both intact and full-length monoclonal antibodies, as well as antibody fragments (Fab, Fab', F(ab')2, Fv, etc.), single-chain variable fragments (scFv), fusion proteins containing an antibody portion, and any other modified immunoglobulin molecule containing an antigen recognition site. Furthermore, "monoclonal antibody" refers to such antibodies produced in any of several ways, including, but not limited to, by hybridoma, phage selection, recombinant expression, and transgenic animals (e.g., expression of human antibodies in transgenic mice).

[0340] Mutation: In the context of the present disclosure, the terms "mutation" and "amino acid substitution" (sometimes simply referred to as "substitution"), as defined above, are considered interchangeable. In some aspects, the term mutation refers to the deletion, insertion, or substitution of any nucleotide, by chemical, enzymatic, or any other means, in a nucleic acid encoding an antibody germline gene, such that the amino acid sequence of the resulting polypeptide is altered at one or more amino acid residues. In some embodiments, a mutation in a nucleic acid sequence disclosed herein results in an amino acid substitution. In other aspects, a mutation of a codon in a nucleic acid sequence disclosed herein, where the resulting codon is a synonymous codon, does not result in an amino acid substitution. Thus, in some aspects, a nucleic acid sequence disclosed herein can be codon optimized by introducing one or more synonymous codon changes. Such codon optimization can, for example, (i) improve protein yield in recombinant protein expression, or (ii) improve the stability, half-life, or other desired properties of mRNA or DNA encoding a binding molecule disclosed herein, when such mRNA or DNA is administered to a subject in need thereof.

[0341] Patient: As used herein, "patient" refers to a subject who may be seeking or in need of treatment, who is requesting treatment, who is currently undergoing treatment, who will undergo treatment in the future, or who is under the supervision of a trained professional for a particular disease or condition.

[0342] Pharmaceutical composition: The term "pharmaceutical composition" refers to a preparation in a form such that the biological activity of an active ingredient (e.g., a binding molecule disclosed herein, such as an antibody) is effective, and the preparation does not contain additional components that are unacceptably toxic to the subject to which the composition is administered. Such compositions are sterile.

[0343] Pharmaceutically acceptable: The phrase "pharmaceutically acceptable" is used herein to refer to those compounds, substances, compositions, and / or dosage forms that are, within the scope of sound medical judgment, suitable for use in contact with the tissues of humans and animals without undue toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit / risk ratio. Generally, approval by a federal or state regulatory agency (or listing in the U.S. Pharmacopeia or other generally recognized pharmacopeia) for use in animals, and more particularly in humans, means that such a compound, substance, composition, and / or dosage form is pharmaceutically acceptable. A compound, substance, composition, and / or dosage form that is generally accepted as safe for therapeutic purposes is "therapeutically acceptable." A compound, substance, composition, and / or dosage form that is generally accepted as safe for diagnostic purposes is "diagnotically acceptable."

[0344] Pharmaceutically acceptable excipient: As used herein, the phrase "pharmaceutically acceptable excipient" refers to any ingredient other than the compounds described herein (e.g., a vehicle capable of suspending or dissolving an active compound) that has substantially non-toxic and non-inflammatory properties in patients. Excipients can include, for example: anti-adherents, antioxidants, binders, coating agents, compression aids, disintegrants, dyes (colorants), emollients, emulsifiers, fillers (excipients), film-forming or coating agents, flavors, fragrances, glidants (flow enhancers), lubricants, preservatives, printing inks, adsorbents, suspending or dispersing agents, sweeteners, and wetting water. Exemplary additives include, but are not limited to, butylated hydroxytoluene (BHT), calcium carbonate, calcium phosphate (dibasic), calcium stearate, croscaromellose, cross-linked polyvinylpyrrolidone, citric acid, crospovidone, cysteine, ethylcellulose, gelatin, hydroxypropyl cellulose, hydroxypropylmethylcellulose, lactose, magnesium stearate, maltitol, mannitol, methionine, methylcellulose, methylparaben, microcrystalline cellulose, polyethylene glycol, polyvinylpyrrolidone, povidone, pregelatinized starch, propylparaben, retinyl palmitate, shellac, silicon dioxide, sodium carboxymethylcellulose, sodium citrate, sodium starch glycolate, sorbitol, starch (corn), stearic acid, sucrose, talc, titanium dioxide, vitamin A, vitamin E, vitamin C, and xylitol.

[0345] An excipient that is generally accepted as safe for therapeutic purposes is a "therapeutically acceptable excipient." An excipient that is generally accepted as safe for diagnostic purposes is a "diagnostically acceptable excipient."

[0346] Pharmaceutically acceptable salts: The present disclosure also includes pharmaceutically acceptable salts of the compounds described herein. As used herein, "pharmaceutically acceptable salts" refers to derivatives of the disclosed compounds, in which the parent compound is modified by converting an acidic or basic moiety present therein into its salt form (e.g., by reacting the free base with a suitable organic acid). Examples of pharmaceutically acceptable salts include, but are not limited to, inorganic or organic acid salts of basic residues such as amines; alkali or organic salts of acidic residues such as carboxylic acids; and the like. Representative acid addition salts include acetate, acetic acid, adipate, alginate, ascorbate, aspartate, benzenesulfonate, benzenesulfonic acid, benzoate, bisulfate, borate, butyrate, camphorate, camphorsulfonate, citrate, cyclopentanepropionate, digluconate, dodecyl sulfate, ethanesulfonate, fumarate, glucoheptonate, glycerophosphate, hemisulfate, heptonate, hexanoate, hydrobromide, hydrochloride, hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate, lactate, laurate, lauryl sulfate, and maltodextrin. Representative alkali or alkaline earth metal salts include sodium, lithium, potassium, calcium, magnesium, and the like, as well as non-toxic ammonium, quaternary ammonium, and amine cations, including, but not limited to, ammonium, tetramethylammonium, tetraethylammonium, methylamine, dimethylamine, trimethylamine, triethylamine, and ethylamine. Pharmaceutically acceptable salts of the present disclosure include the conventional non-toxic salts of the parent compound formed, for example, from non-toxic inorganic or organic acids. The pharmaceutically acceptable salts of the present disclosure can be synthesized from parent compounds containing basic or acidic moieties by conventional chemical methods. Generally, these salts can be prepared by reacting these compounds in the form of free acid or free base with a stoichiometric amount of an appropriate base or acid in water, or in an organic solvent, or in a mixture of the two; generally, non-aqueous media such as ether, ethyl acetate, ethanol, isopropanol, or acetonitrile are used. Lists of suitable salts can be found in Remington's Pharmaceutical Sciences, 17th Edition, Mack Publishing Company, Easton, Pa., 1985, p. 1418; Pharmaceutical Salts: Properties, Selection, and Use, P.H. Stahl and C.G. Wermuth (eds.), Wiley-VCH, 2008; and Berge et al., Journal of Pharmaceutical Science, Vol. 66, pp. 1-19 (1977), each of which is incorporated herein by reference in its entirety.

[0347] Pharmaceutically acceptable solvate: As used herein, the term "pharmaceutically acceptable solvate" refers to a compound of the present invention in which molecules of a suitable solvent are incorporated into the crystal lattice. The suitable solvent is physiologically tolerated at the administered dosage. For example, solvates can be prepared by crystallization, recrystallization, or precipitation from a solution containing an organic solvent, water, or a mixture thereof. Examples of suitable solvents include ethanol, water (e.g., monohydrate, dihydrate, and trihydrate), N-methylpyrrolidinone (NMP), dimethyl sulfoxide (DMSO), N,N'-dimethylformamide (DMF), N,N'-dimethylacetamide (DMAC), 1,3-dimethyl-2-imidazolidinone (DMEU), 1,3-dimethyl-3,4,5,6-tetrahydro-2-(1H)-pyrimidinone (DMPU), acetonitrile (ACN), propylene glycol, ethyl acetate, benzyl alcohol, 2-pyrrolidone, benzyl benzoate, etc. When water is the solvent, the solvate is referred to as a "hydrate."

[0348] Pharmacokinetics: As used herein, "pharmacokinetics" refers to any one or more properties of a molecule or compound as it relates to determining the fate of a substance administered to a living organism. Pharmacokinetics is divided into several areas, including the extent and rate of absorption, distribution, metabolism, and excretion. This is commonly referred to as ADME, where: (A) absorption is the process of a substance entering the blood circulation; (D) distribution is the dispersion or spread of a substance throughout the body's fluids and tissues; (M) metabolism (or biotransformation) is the irreversible conversion of a parent compound to daughter metabolites; and (E) excretion (or elimination) refers to the removal of a substance from the body. In rare instances, some drugs irreversibly accumulate in body tissues.

[0349] Polynucleotide: As used herein, the term "polynucleotide" refers to a polymer of nucleotides of any length, including ribonucleotides, deoxyribonucleotides, analogs thereof, or mixtures thereof. The term refers to the primary structure of the molecule. Thus, the term includes triple-, double-, and single-stranded deoxyribonucleic acid ("DNA"), as well as triple-, double-, and single-stranded ribonucleic acid ("RNA"). It also includes modified forms of polynucleotides, for example, by alkylation and / or by capping, as well as unmodified forms thereof. More specifically, the term "polynucleotide" includes polydeoxyribonucleotides (containing 2-deoxy-D-ribose), spliced ​​or unspliced ​​polyribonucleotides (containing D-ribose), including tRNA, rRNA, hRNA, siRNA, and mRNA, any other type of polynucleotide that is an N- or C-glycoside of a purine or pyrimidine base, and other polymers containing non-nucleotide backbones, such as polyamides (e.g., peptide nucleic acids, "PNAs"), and polymorpholino polymers, and other synthetic sequence-specific nucleic acid polymers, provided that these polymers contain nucleobases in configurations that allow for base pairing and base stacking as found in DNA and RNA. In certain embodiments, the polynucleotide includes mRNA. In other embodiments, the mRNA is synthetic mRNA. In some embodiments, the synthetic mRNA contains at least one unnatural nucleobase. In some embodiments, all of a certain class of nucleobases are replaced with unnatural nucleobases (e.g., all uridines in a polynucleotide disclosed herein are replaced with unnatural nucleobases, such as 5-methoxyuridine). In some embodiments, a polynucleotide (e.g., synthetic RNA or DNA) contains only natural nucleobases, i.e., A, C, T, and U in the case of synthetic DNA, or A, C, T, and U in the case of synthetic RNA.

[0350] Those skilled in the art will understand that while T bases in the codon maps disclosed herein are present in DNA, the T bases are replaced by U bases in the corresponding RNA. For example, in DNA form, a codon-nucleotide sequence disclosed herein, e.g., a vector or in vitro translation (IVT) template, has its T base transcribed as a U base in its corresponding translated mRNA. In this regard, a codon-optimized DNA sequence (containing T) and its corresponding RNA sequence (containing U) are considered codon-optimized nucleotide sequences of the invention. Those skilled in the art will also understand that equivalent codon maps are generated by replacing one or more bases with unnatural bases. Thus, for example, a TTC codon (DNA map) would correspond to a UUC codon (RNA map), which in turn would correspond to a ΨΨC codon (RNA map, with U replaced by a pseudouridine).

[0351] Under conditions that allow hydrogen bond formation between the N3-H and C4-oxy of thymidine and the N1 and C6-NH2 of adenosine, respectively, and between the C2-oxo, N3 and C4-NH2 of cytidine and the C2-NH2, N'-H and C6-oxy of guanosine, respectively, standard AT and GC base pairs are formed.Thus, for example, guanosine (2-amino-6-oxy-9-β-D-ribofuranosyl-purine) can be modified to form isoguanosine (2-oxy-6-amino-9-β-D-ribofuranosyl-purine).Such modification results in a nucleoside base that no longer effectively forms standard base pairs with cytosine. However, modification of cytosine (1-β-D-ribofuranosyl-2-oxy-4-amino-pyrimidine) to form isocytosine (1-β-D-ribofuranosyl-2-amino-4-oxy-pyrimidine-) results in a modified nucleoside that does not base pair efficiently with guanosine but does base pair with isoguanosine (U.S. Patent No. 5,681,702 to Collins et al.). Isocytosine is available from Sigma Chemical Co. (St. Louis, Mo.); isocytidine is prepared by the method described by Switzer et al. (1993) Biochemistry 32:10489-10496 and references cited therein; 2'-deoxy-5-methyl-isocytidine is prepared by the method described by Tor et al. (1993) J. Am. Chem. Soc. 115:4461-4464. 467 and the references cited therein; and isoguanine nucleotides can be prepared using the methods described by Switzer et al., 1993, supra, and Mantsch et al. (1993) Biochem. 14:5593-5601, or by the method described in U.S. Pat. No. 5,780,610 to Collins et al. Other unnatural base pairs can be synthesized by the method described in Piccirilli et al. (1990) Nature 343:33-37 for the synthesis of 2,6-diaminopyrimidine and its complement (1-methylpyrazolo-[4,3]pyrimidine-5,7-(4H,6H)-dione). Other such modified nucleotide units that form unique base pairs are known, such as those described in Leach et al. (1992) J. Am. Chem. Soc. 114:3675-3683, supra, and Switzer et al.

[0352] Polypeptide: The terms "polypeptide," "peptide," and "protein" are used interchangeably herein to refer to polymers of amino acids of any length. A polymer can contain modified amino acids. The term also encompasses naturally modified amino acid polymers or amino acid polymers modified by intervention, for example, disulfide bond formation, glycosylation, lipidation, acetylation, phosphorylation, or any other manipulation or modification, such as conjugation with a labeling moiety. Also included in this definition are, for example, polypeptides containing one or more analogs of an amino acid (including, for example, unnatural amino acids such as homocysteine, ornithine, p-acetylphenylalanine, D-amino acids, and creatine), and other modifications known in the art.

[0353] As used herein, the term refers to proteins, polypeptides, and peptides of any size, structure, or function. Polypeptides include the above-mentioned gene products, natural polypeptides, synthetic polypeptides, homologs, orthologs, paralogs, fragments, and other equivalents, variants, and analogs. Polypeptides can be single polypeptides or multimolecular complexes such as dimers, trimers, or tetramers. They can also include single-chain or multi-chain polypeptides. Disulfide linkages are most common in multi-chain polypeptides. The term polypeptide can also apply to amino acid polymers in which one or more amino acid residues are artificial chemical analogs of the corresponding naturally occurring amino acids. In some embodiments, a "peptide" can be 50 amino acids or less in length, e.g., about 5, 10, 15, 20, 25, 30, 35, 40, 45, or 50 amino acids in length.

[0354] Prevention: As used herein, the term "preventing" refers to partially or completely delaying the onset of a disease, disorder, and / or condition; partially or completely delaying the onset of one or more of the symptoms, characteristics, or clinical signs of a particular disease, disorder, and / or condition; partially or completely delaying the onset of one or more of the symptoms, characteristics, or signs of a particular disease, disorder, and / or condition; partially or completely delaying the progression from a particular disease, disorder, and / or condition; and / or reducing the risk of developing pathology associated with a disease, disorder, and / or condition.

[0355] Prophylactic: As used herein, "prophylactic" refers to a therapeutic process or a course of action used to prevent the onset of a disease or condition, or to prevent or delay bleeding episodes, e.g., symptoms associated with hemophilia.

[0356] Prophylaxis: As used herein, "prophylaxis" refers to measures taken to maintain health and to prevent or delay the onset of bleeding episodes or symptoms associated with a disease or condition.

[0357] Recombinant: A "recombinant" polypeptide or protein refers to a polypeptide or protein produced by recombinant DNA methods. Recombinantly produced polypeptides and proteins expressed in engineered host cells are considered isolated for the purposes of the present invention, as are natural or recombinant polypeptides that have been separated, fractionated, or partially or substantially purified by any appropriate technique. The polypeptides disclosed herein can be recombinantly produced using methods known in the art. Alternatively, the proteins and peptides disclosed herein can be chemically synthesized.

[0358] Similarity: As used herein, the term "similarity" refers to the overall relatedness between polymer molecules, e.g., polynucleotide molecules (e.g., DNA molecules and / or RNA molecules) and / or polypeptide molecules. Calculations of percent similarity between polymer molecules to each other can be performed in the same manner as calculating percent identity, except that percent similarity takes into account conservative substitutions, as understood in the art.

[0359] Subject: "Subject" or "individual" or "animal" or "patient" or "mammal" means any subject, particularly a mammalian subject, for whom diagnosis, prognosis, or treatment is desired. Mammalian subjects include, but are not limited to, humans, livestock, farm animals, zoo animals, sport animals, pet animals such as dogs, cats, guinea pigs, rabbits, rats, mice, horses, cattle, and cows; primates such as apes, monkeys, orangutans, and chimpanzees; canines such as dogs and wolves; felines such as cats, lions, and tigers; equines such as horses, donkeys, and zebras; food animals such as bears, cows, pigs, and sheep; ungulates such as deer and giraffes; rodents such as mice, rats, hamsters, and guinea pigs; and the like. In certain embodiments, the mammal is a human subject. In other embodiments, the subject is a human patient. In certain embodiments, the subject is a human patient or cells thereof, whether in vivo, in vitro or ex vivo, amenable to the methods described herein.

[0360] Substantially: As used herein, the term "substantially" refers to a quantitative state indicating a total or near total degree or degree of a desired characteristic or property. Those skilled in the art of biology will understand that biological and chemical phenomena do not, if at all, proceed to completion and / or perfection, or achieve or avoid absolute results. Thus, the term "substantially" is used herein to capture the potential lack of perfection inherent in many biological and chemical phenomena.

[0361] Substantially equivalent: As used herein, as it relates to the time difference between doses, this term means plus / minus 2%.

[0362] Substantially simultaneously: As used herein, and in relation to multiple doses, this term means within 2 seconds.

[0363] Suffering from: An individual "suffering from" a disease, disorder, and / or condition has been diagnosed with or exhibits one or more symptoms of the disease, disorder, and / or condition.

[0364] Susceptible: An individual who is susceptible to a disease, disorder, and / or condition may not have been diagnosed with and / or exhibit symptoms of the disease, disorder, and / or condition, but has an underlying tendency to develop the disease or its symptoms. Individuals who are susceptible to a disorder and / or condition (e.g., cancer) can be characterized by one or more of the following: (1) a genetic mutation associated with the development of the disease, disorder, and / or condition; (2) a genetic polymorphism associated with the development of the disease, disorder, and / or condition; (3) an increase and / or decrease in the expression level and / or activity of a protein and / or nucleic acid associated with the disease, disorder, and / or condition; (4) habits and / or lifestyles associated with the development of the disease, disorder, and / or condition; (5) a family history of the disease, disorder, and / or condition; or (6) exposure to and / or infection by a microorganism associated with the development of the disease, disorder, and / or condition. In some embodiments, individuals who are susceptible to a disease, disorder, and / or condition are predicted to develop the disease, disorder, and / or condition. In some embodiments, individuals who are susceptible to a disease, disorder, and / or condition will not develop the disease, disorder, and / or condition.

[0365] Therapeutic Agent: The term "therapeutic agent" or "drug" refers to a molecular entity that has a therapeutic, diagnostic, and / or prophylactic effect and / or induces a desired biological and / or pharmacological effect when administered to a subject. For example, in some embodiments, a bispecific antibody disclosed herein can be a therapeutic agent. In some embodiments, the drug is another molecule (e.g., a clotting factor, cofactor, etc.) that is co-administered as part of a combination therapy with at least one of the antibodies disclosed herein.

[0366] Therapeutically effective amount: As used herein, the term "therapeutically effective amount" means an amount of an agent (e.g., nucleic acid, drug, therapeutic agent, diagnostic agent, prophylactic agent, etc.) that, when administered to a subject suffering from or susceptible to an infection, disease, disorder and / or condition, would be sufficient to treat, ameliorate the symptoms of, diagnose, prevent, and / or delay the onset of the infection, disease, disorder and / or condition.

[0367] Therapeutically effective outcome: As used herein, the term "therapeutically effective outcome" means an outcome sufficient to treat, ameliorate the symptoms of, diagnose, prevent, and / or delay the onset of an infection, disease, disorder, and / or condition in a subject suffering from or susceptible to the infection, disease, disorder, and / or condition.

[0368] Treating, treatment, therapy: As used herein, the term "treat" or "treatment" or "therapy" or grammatical variations thereof refers to partially or completely alleviating, ameliorating, improving, relieving, delaying the onset of, preventing the progression of, reducing the severity of, and / or reducing the incidence of one or more symptoms or characteristics of a bleeding disease, disorder, or condition, e.g., hemophilia. For example, "treating" a bleeding disorder can refer to preventing bleeding, reducing the frequency and / or severity of bleeding episodes, etc. Treatment can be administered to subjects who do not show signs of the disease, disorder, and / or condition and / or who show only early signs of the disease, disorder, and / or condition, for the purpose of reducing the risk of developing pathology associated with the disease, disorder, and / or condition.

[0369] Vector: A "vector" is a nucleic acid molecule, particularly a self-replicating one, that transfers an inserted nucleic acid molecule into and / or between host cells. The term includes vectors that function primarily to insert DNA or RNA into a cell (e.g., chromosomal integration), replicating vectors that function primarily to replicate DNA or RNA, and expression vectors that function to transcribe and / or translate DNA or RNA. In some embodiments, administration and / or expression of nucleic acids (DNA or RNA, such as mRNA) encoding the binding molecules disclosed herein can be performed in vitro (e.g., during recombinant protein production), while In other cases, this can be done in vivo (e.g., administration of mRNA to a subject), or ex vivo (e.g., DNA or RNA introduced into autologous or heterologous cells for administration to a subject in need thereof). Similarly, vectors that provide more than one of the functions as described are included.

[0370] II. Anti-FIX and Anti-FX Binding Molecules The present disclosure provides antibodies that bind to factor IX and factor X and their antigen-binding portions. These antibodies are capable of preferentially binding to specific functional forms of these coagulation factors. For example, in some embodiments, the disclosed antibodies against FIX preferentially bind activated FIX (FIXa), e.g., free FIXa or FIXa, that is covalently linked to a pseudosubstrate at the active site (FXa+EGR-CMK). In other embodiments, the disclosed antibodies preferentially bind FIXa-SM over free FIXa or FIX zymogen. In still other embodiments, the disclosed antibodies preferentially bind free FIXa over FIXa-SM or FIX zymogen. In contrast, in some embodiments, the disclosed antibodies against FX preferentially bind FX zymogen (FXz) over activated FX (FXa). This preferential binding is important for generating bispecific molecules containing an anti-FIXa portion and an anti-FXz portion that can specifically and simultaneously bind FIXa and FXz. Factor VIII is a soluble factor (FIXa) that binds to Ca. 2+and is a cofactor for FIXa that, in the presence of phospholipids, forms a complex with FX, converting FX to activated FXa. Thus, antibody-mediated complex formation between FIXa and FXz mimics the action of FVIIIa.

[0371] In yet other embodiments, some disclosed antibodies preferentially bind to FIX zymogen over free FIXa or FIXa-SM ("anti-FIXz antibodies"). Thus, anti-FIXz antibodies can be used to generate bispecific molecules comprising anti-FIXz and anti-FX antibodies (e.g., anti-FXz or anti-FXa antibodies).

[0372] In certain embodiments, some disclosed anti-FX antibodies preferentially bind FXa over FXz ("anti-FXa antibodies"). Anti-FXa antibodies can be used to generate bispecific molecules comprising anti-FXa and anti-FIX antibodies (e.g., anti-FIXa or anti-FIXz antibodies).

[0373] Thus, antibody-mediated complex formation between FIX and FX can be used to bypass FVIII replacement therapy, particularly in subjects who have developed or are at risk of developing antibodies to FVIII.

[0374] The present disclosure also provides bispecific binding molecules that bind to FX (FXz and / or FXa) and FIX (FIXz and / or FIXa). In one embodiment, the bispecific binding molecule can be a combination of either an anti-FIXa antibody or an anti-FIXz antibody with either an anti-FXa antibody or an anti-FXz antibody. In some embodiments, the bispecific binding molecule specifically binds to FXz, FIXz, and FIXa, but has no detectable binding to FXa. In certain embodiments, the bispecific binding molecule has different binding affinities (e.g., K D In other embodiments, the bispecific binding molecule binds to FIXz, FIXa, and FXz with a K of less than 1 μM for each of FIXz, FIXa, and FXz. D(e.g., 8 nM, 2 nM, or 20 nM, respectively).

[0375] (a) Anti-FIXa binding molecule The present disclosure provides anti-FIX binding molecules, e.g., anti-FIX antibodies, or molecules comprising antigen-binding portions thereof, that preferentially bind activated FIX (FIXa) over FIX zymogen. .

[0376] Factor IX (FIX) is synthesized by stem cells as a prozymogen precursor, which requires extensive post-transcriptional modification. The preprozymogen contains a prepeptide (hydrophobic signal peptide) at its amino terminus that transports the growing polypeptide into the lumen of the endoplasmic reticulum. This signal peptide is cleaved by a signal peptidase once inside the ER. The propeptide serves as a recognition element for vitamin K-dependent carboxylase (γ-glutamylcarboxylase), which modifies 12 glutamic acid residues to gamma-carboxyglutamyl (Gla) residues. These residues are required for binding to anionic phospholipid surfaces via Ca2+-dependent binding.

[0377] The amino acid sequence of the preproFIX zymogen is presented below (the signal sequence is underlined (1-28); the propeptide sequence (29-46) is in bold): [ka]

[0378] After cleavage of the signal peptide and propeptide, FIX is in its zymogen form. The FIX zymogen thus circulates as a single polypeptide chain of 415 amino acids. See Vysotchin et al., J. Biol. Chem. 268:8436 (1993). In one embodiment, the FIX zymogen is amino acids 47-461 of SEQ ID NO: 764. In another embodiment, the FIX zymogen is amino acids 47-461 of SEQ ID NO: 764, where amino acid residue 180 is alanine instead of arginine (i.e., inactivatable FIX).

[0379] The FIX zymogen is activated by FXIa or by the tissue factor / FVIIa complex. The first cleavage occurs at Arg191 (Arg145 in the mature FIX sequence) to generate inactive FIX-alpha. The second cleavage at Arg226 (Arg180 in the mature FIX sequence) removes 35 amino acids from the FIX activation peptide, resulting in the catalytically active molecule FIXa-beta. This catalytically active FIXa, which does not bind to FVIIIa, is also referred to herein as free FIXa. The resulting heterodimer is held together by a disulfide bridge from Cys178 to Cys335. The serine protease contains the catalytic triad: His267, Asp315, and Ser411. Upon cleavage of Arg226, Val227 can form a salt bridge with Asp410, a characteristic of an active serine protease. In one embodiment, free FIXa consists of amino acids 47 to 191 of SEQ ID NO: 764 and amino acids 227 to 461 of SEQ ID NO: 764, in which amino acids 178 and 335 of SEQ ID NO: 764 form a disulfide bond.

[0380] However, the activity of free FIXa is known to be similar to that of the FIX zymogen. Complex formation with the cofactor FVIIIa constitutes the crucial second phase of activation, after which the latent FIXase complex reaches an approximately 200,000-fold enhanced activity that is strictly specific for the physiological substrate FX and is restricted to the surface of activated platelets (van Dieije). (N et al., J Biol Chem. 1981 Apr. 10;256(7):3433-42). Activation of this macromolecule is assisted by small molecular weight agonists, including Ca2+ (Mathur et al., Biol. Chem. 272 ​​(1997) 23418-23426). Several lines of evidence indicate that Ca2+ binding is accompanied by a conformational rearrangement (Bajaj et al., Proc. Natl. Acad. Sci. USA 89 (1992) 152-156; Enfield and Thompson, Blood 64 (1984) 821-831). This highly active FIXa in the tenase complex is mimicked by covalent attachment of a pseudosubstrate (e.g., Glu-Gly-Arg-chloromethylketone (EGR-CMK)) to the active site of FIXa (FXa+EGR-CMK, also called FIXa-SM). Thus, FIXa-SM can be used as an important tool to distinguish antibodies, or antibody-binding portions thereof, that preferentially bind highly active FIXa (in the tenase complex) compared to free FIXa.

[0381] Tripeptide chloromethyl ketones are generally accepted in the art as pseudosubstrates; the tripeptide sequence is the natural substrate sequence cleaved by certain enzymes, and the CMK moiety allows the tripeptide to react with the active site serine, irreversibly trapping it in the active site. Consequently, when the enzyme binds to the pseudosubstrate, it must assume the substrate's bound, i.e., true active, conformation. See Brandsteter et al. (1995) Proc. Natl. Acad. Sci. USA 92(21):9796-80 and Hopfner et al. (1999) Structure 7(8):989-96.

[0382] The term "FIX zymogen" can be used interchangeably herein with "FIXz," "FIX precursor," "inactivated FIX," "non-activated FIX," or "non-activated FIX precursor." In one embodiment, FIX zymogen (FIXz) includes the non-activated FIX precursor, in which the activation peptide (e.g., the 35 activation peptide represented as amino acids 146-180 of SEQ ID NO: 764) (mature numbering) is not cleaved from the precursor. FIX zymogens can include any natural or engineered variant. A non-limiting example of a FIX zymogen is set forth in SEQ ID NO: 764. In another embodiment, the FIX zymogen is an activatable form of FIX (FIXn), which is engineered to be inactive in the presence of factor XIa, the active plasma thromboplastin precursor. An example of an activatable form of FIX can be FIX with an arginine to alanine mutation at position 180 (mature numbering), which prevents its activation and maintains factor IX in the zymogen form (FIXz). The FIX zymogen can optionally contain a signal peptide and / or a propeptide.

[0383] The term "activated FIX" can be used interchangeably herein with "FIXa." In one embodiment, activated FIX is wild-type native FIXa (also referred to herein as "wild-type FIXa"). In another embodiment, FIXa includes non-native FIXa, such as FIXa conformational variants. For example, FIXa can be FIXa-SM, which is designed to have the same conformation as wild-type native FIXa bound to its substrate, FX. In certain embodiments, FIXa-SM is activated FIX with a pseudosubstrate covalently bound to the active site, which is intended to mimic the most active conformation of activated FIX.

[0384] FIX zymogen and FIXa can comprise FIX variants. In one embodiment, FIX variants are cloned as described in U.S. Patent Nos. 4,770,999 and 7,700,734, where a cDNA encoding human factor IX is isolated, characterized, and cloned into an expression vector (see, e.g., Choo et al. (See, e.g., Nature 299:178-180 (1982); Fair et al., Blood 64:194-204 (1984); and Kurachi et al., Proc. Natl. Acad. Sci. USA 79:6461-6464 (1982). One particular variant of FIX, the R338L FIX (Padua) variant characterized by Simioni et al. in 2009, contains a gain-of-function mutation, which correlates with an approximately eight-fold improvement in activity of the Padua variant compared to native FIX. A FIX variant also includes any FIX polypeptide with one or more conservative amino acid substitutions that do not affect the FIX activity of the FIX polypeptide.

[0385] Thus, the present disclosure provides an antibody (e.g., an isolated antibody) or antigen-binding portion thereof that specifically binds to activated factor IX (FIXa) (e.g., free FIXa or FIXa-SM), wherein the anti-FIXa antibody or antigen-binding portion thereof preferentially binds to FIXa in the presence of FIXa and FIX zymogen ("anti-FIXa antibody or antigen-binding portion thereof").

[0386] In some aspects, the anti-FIXa antibody or antigen-binding portion thereof binds to FIXa with a higher binding affinity than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof to FIXz. In one embodiment, the binding affinity is K D It is expressed as:

[0387] The present disclosure also provides an isolated anti-FIXa antibody or antigen-binding portion thereof that binds to FIXa with a higher binding affinity than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof to FIXz. In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof has a K of about 100 nM or less, (e.g., 1 nM to 100 nM or 0.1 nM to 100 nM), about 95 nM or less, about 90 nM or less, about 85 nM or less, about 80 nM or less, about 75 nM or less, about 70 nM or less, about 65 nM or less, about 60 nM or less, about 55 nM or less, about 50 nM or less, about 45 nM or less, about 40 nM or less, about 35 nM or less, about 30 nM or less, about 25 nM or less, about 20 nM or less, about 15 nM or less, about 10 nM or less, about 5 nM or less, or about 1 nM or less, as determined by a biolayer interferometry (BLI) assay. D In other embodiments, the anti-FIXa antibody or antigen-binding portion thereof binds to FIXa with a K of about 10 nM or less, about 9 nM or less, about 8 nM or less, about 7 nM or less, about 6 nM or less, about 5 nM or less, about 4 nM or less, about 3 nM or less, about 2 nM or less, about 1 nM or less, about 0.5 nM or less, about 0.2 nM or less, about 0.1 nM or less, or about 0.05 nM or less. D In still other embodiments, the anti-FIXa antibody or antigen-binding portion thereof binds to FIXa with a K of 1 nM to 100 nM, 1 nM to 90 nM, 1 nM to 80 nM, 1 nM to 70 nM, 1 nM to 60 nM, 1 nM to 50 nM, 1 nM to 40 nM, 1 nM to 30 nM, 1 nM to 20 nM, 1 nM to 10 nM, 0.1 nM to 100 nM, 0.1 nM to 90 nM, 0.1 nM to 80 nM, 0.1 nM to 70 nM, 0.1 nM to 60 nM, 0.1 nM to 50 nM, 0.1 nM to 40 nM, 0.1 nM to 30 nM, 0.1 nM to 20 nM, 0.1 nM to 10 nM, or 0.1 nM to 1 nM. D and binds to FIXa.

[0388] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, cross-competes with a reference antibody selected from the group consisting of the antibodies in Figures 3A, 3B, and / or 3C. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, binds to the same epitope as a reference antibody selected from the group consisting of the antibodies in Figures 3A, 3B, and / or 3C. In some embodiments, the reference antibody is selected from BIIB-9-484, BIIB-9-440, BIIB-9-882, BIIB-9-460, BIIB-9-433, and any combination thereof.

[0389] In further embodiments, anti-FIXa antibodies or antigen-binding portions thereof can be further divided into the following three classes: Class I: anti-FIXa antibodies or antigen-binding portions thereof that bind preferentially to FIXa-SM over free FIXa or FIXz (antibodies in Figure 3A ); Class II: anti-FIXa antibodies or antigen-binding portions thereof that bind preferentially to free FIXa over FIXa-SM or FIXz (antibodies in Figure 3B); and Class III: Anti-FIXa antibodies or antigen-binding portions thereof that bind approximately equally to free FIXa and FIXa-SM, but do not bind significantly to FIXz (antibodies in Figure 3C).

[0390] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 3A. In other embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, binds to the same epitope as the reference antibody selected from the group consisting of the antibodies in Figure 3A. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 3B. In other embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, binds to the same epitope as the reference antibody selected from the group consisting of the antibodies in Figure 3B. In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, cross-competes with a reference antibody selected from the group consisting of the antibodies in Figure 3C. In other embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, binds to the same epitope as the reference antibody selected from the group consisting of the antibodies in Figure 3C.

[0391] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR3 is (i) a VH CDR3 sequence identical to a VH CDR3 sequence selected from the group consisting of the VH CDR3 sequences in Figure 3A; or (ii) a VH CDR3 sequence identical to a VH CDR3 sequence selected from the group consisting of the VH CDR3 sequences in Figure 3A, except for one, two, or three amino acid substitutions; Includes.

[0392] In other embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR3 is (i) a VH CDR3 sequence identical to a VH CDR3 sequence selected from the group consisting of the VH CDR3 sequences in Figure 3B; or (ii) a VH CDR3 sequence identical to a VH CDR3 sequence selected from the group consisting of the VH CDR3 sequences in Figure 3B, except for one, two, or three amino acid substitutions; Includes.

[0393] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR3 is (i) a VH CDR3 sequence identical to a VH CDR3 sequence selected from the group consisting of the VH CDR3 sequences in Figure 3C; or (ii) a VH CDR3 sequence identical to a VH CDR3 sequence selected from the group consisting of the VH CDR3 sequences in Figure 3C, except for one, two, or three amino acid substitutions. Includes.

[0394] In some aspects, the amino acid substitutions are conservative amino acid substitutions. In other aspects, the amino acid substitutions are back mutations.

[0395] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises VH CDR1, VH CDR2, and VH CDR3, and the VH CDR3 sequence comprises ARDX1X2X3X4X5X6YYX7MDV (sequence number 753), wherein X1 is V or G, X2 is G or V, X3 is G or R, X4 is Y or V, X5 is A or S, X6 is G or D, and X7 is G or absent.

[0396] Those skilled in the art understand that when a position is described as "absent" or "non-existent" in a consensus sequence, such absence does not indicate a break in the polypeptide chain. These terms simply reflect the occurrence of insertions and deletions in the amino acid chain observed in a multiple sequence alignment. Thus, when two sequences, one of which contains an amino acid insertion, are aligned to generate a consensus sequence, the sequence without the insertion is expected to have an "absent" ("none") amino acid at that position.

[0397] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR3 sequence comprises an amino acid sequence selected from ARDVGGYAGYYGMDV (SEQ ID NO: 905; VH CDR3 for BIIB-9-484; BIIB-9-1335; and BIIB-9-1336), ARDISTDGESSLYYYMDV (SEQ ID NO: 901; BIIB-9-460), ARGPTDSSGYLDMDV (SEQ ID NO: 1186; BIIB-9-882), ARSPRHKVRGPNWFDP (SEQ ID NO: 899; BIIB-9-440), or ARDGPRVSDYYMDV (SEQ ID NO: 912; BIIB-9-619). In some embodiments, the VH CDR3 sequences disclosed herein can comprise one, two, or three amino acid substitutions.

[0398] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR1 sequence is: (i) a VH CDR1 sequence identical to a sequence selected from the group consisting of the VH CDR1 sequences disclosed in Figure 3A; or (ii) the VH disclosed in Figure 3A, except for one, two, or three amino acid substitutions a VH CDR1 sequence identical to a sequence selected from the group consisting of: Includes.

[0399] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR1 sequence is: (i) a VH CDR1 sequence identical to a sequence selected from the group consisting of the VH CDR1 sequences disclosed in Figure 3B; or (ii) the VH disclosed in Figure 3B except for one, two, or three amino acid substitutions a VH CDR1 sequence identical to a sequence selected from the group consisting of: Includes.

[0400] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR1 sequence is: (i) a VH CDR1 sequence identical to a sequence selected from the group consisting of the VH CDR1 sequences disclosed in Figure 3C; or (ii) the VH disclosed in Figure 3C except for one, two, or three amino acid substitutions a VH CDR1 sequence identical to a sequence selected from the group consisting of: Includes.

[0401] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR2 sequence is: (i) a VH CDR2 sequence identical to a sequence selected from the group consisting of the VH CDR2 sequences disclosed in Figure 3A; or (ii) the VH disclosed in Figure 3A, except for one, two, or three amino acid substitutions a VH CDR2 sequence identical to a sequence selected from the group consisting of: Includes.

[0402] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR2 sequence is: (i) a VH CDR2 sequence identical to a sequence selected from the group consisting of the VH CDR2 sequences disclosed in Figure 3B; or (ii) the VH disclosed in Figure 3B except for one, two, or three amino acid substitutions a VH CDR2 sequence identical to a sequence selected from the group consisting of: Includes.

[0403] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH CDR1, a VH CDR2, and a VH CDR3, wherein the VH CDR2 sequence is: (i) a VH CDR2 sequence identical to a sequence selected from the group consisting of the VH CDR2 sequences disclosed in Figure 3C; or (ii) the VH disclosed in Figure 3C except for one, two, or three amino acid substitutions a VH CDR2 sequence identical to a sequence selected from the group consisting of: Includes.

[0404] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR1 sequence is: (i) a VL CDR1 sequence identical to a sequence selected from the group consisting of the VL CDR1 sequences disclosed in Figure 3A; or (ii) the VL disclosed in Figure 3A, except for one, two, or three amino acid substitutions a VL CDR1 sequence identical to a sequence selected from the group consisting of: Includes.

[0405] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR1 sequence is: (i) a VL CDR1 sequence identical to a sequence selected from the group consisting of the VL CDR1 sequences disclosed in Figure 3B; or (ii) the VL disclosed in Figure 3B, except for one, two, or three amino acid substitutions a VL CDR1 sequence identical to a sequence selected from the group consisting of: Includes.

[0406] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR1 sequence is: (i) a VL CDR1 sequence identical to a sequence selected from the group consisting of the VL CDR1 sequences disclosed in Figure 3C, or (ii) the VL disclosed in Figure 3C, except for one, two, or three amino acid substitutions a VL CDR1 sequence identical to a sequence selected from the group consisting of: Includes.

[0407] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR2 sequence is (i) a VL CDR2 sequence identical to a sequence selected from the group consisting of the VL CDR2 sequences in Figure 3A; or (ii) a VL CDR2 sequence identical to a sequence selected from the group consisting of the VL CDR2 sequences in Figure 3A, except for one, two, or three amino acid substitutions. Includes.

[0408] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR2 sequence is (i) a VL CDR2 sequence identical to a sequence selected from the group consisting of the VL CDR2 sequences in Figure 3B; or (ii) a VL CDR2 sequence identical to a sequence selected from the group consisting of the VL CDR2 sequences in Figure 3B, except for one, two, or three amino acid substitutions. Includes.

[0409] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR2 sequence is (i) a VL CDR2 sequence identical to a sequence selected from the group consisting of the VL CDR2 sequences in Figure 3C; or (ii) a VL CDR2 sequence identical to a sequence selected from the group consisting of the VL CDR2 sequences in Figure 3C, except for one, two, or three amino acid substitutions. Includes.

[0410] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR3 sequence is (i) a VL CDR3 sequence identical to a sequence selected from the group consisting of the VL CDR3 sequences disclosed in Figure 3A; or (ii) the VL disclosed in Figure 3A, except for one, two, or three amino acid substitutions a VL CDR3 sequence identical to a sequence selected from the group consisting of: Includes.

[0411] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR3 sequence is (i) a VL CDR3 sequence identical to a sequence selected from the group consisting of the VL CDR3 sequences disclosed in Figure 3B; or (ii) the VL disclosed in Figure 3B, except for one, two, or three amino acid substitutions a VL CDR3 sequence identical to a sequence selected from the group consisting of: Includes.

[0412] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VL CDR3 sequence is (i) a VL CDR3 sequence identical to a sequence selected from the group consisting of the VL CDR3 sequences disclosed in Figure 3C, or (ii) the VL disclosed in Figure 3C, except for one, two, or three amino acid substitutions a VL CDR3 sequence identical to a sequence selected from the group consisting of: Includes.

[0413] The present disclosure also provides an isolated antibody or antigen-binding portion thereof that specifically binds to FIXa, comprising VH CDR1, VH CDR2, and VH CDR3 and VL CDR1, VL CDR2, and VL CDR3, CDR3 is identical to that of the antibodies in Figure 3A: BIIB-9-605, BIIB-9-475, BIIB-9-477, BIIB-9-479, BIIB-9-480, BIIB-9-558, BIIB-9-414, BIIB-9-415, BIIB-9-425, BIIB-9-440, BIIB-9-452, BIIB-9-460, BIIB-9-461, BIIB-9-465, BIIB-9-564, BIIB-9-484, BIIB-9-469, BIIB-9-566, BIIB-9-567, BIIB-9-569, BIIB-9-588, BIIB-9-490, BIIB-9-591, BIIB-9-592, BIIB-9-593, BIIB-9-594, BIIB-9-595, BIIB-9-596, BIIB-9-597, BIIB-9-598, BIIB-9-599, BIIB-9-601, BIIB-9-602, BIIB-9-603, BIIB-9-604, BIIB-9-605, BIIB-9-606, BIIB-9-607, BIIB-9-608, BIIB-9-609, BIIB-9-610, BIIB-9-611, BIIB-9-612, BIIB-9-613, BIIB-9-614, BIIB-9-615, BIIB-9-616, BIIB-9-617, BIIB-9-618, BIIB-9 the VH CDR1, VH CDR2 and VH CDR3 of an anti-FIXa antibody selected from the group consisting of BIIB-9-611, BIIB-9-619, BIIB-9-626, BIIB-9-883, BIIB-9-419, BIIB-9-451, BIIB-9-473, BIIB-9-565, BIIB-9-573, BIIB-9-579, BIIB-9-581, BIIB-9-582, BIIB-9-585, BIIB-9-587, BIIB-9-590, BIIB-9-592, BIIB-9-606, BIIB-9-608, BIIB-9-616, BIIB-9-621, BIIB-9-622, BIIB-9-627, BIIB-9-1335, and BIIB-9-1336; CDR3 and VL CDR1, VL CDR2 and VL CDR3.

[0414] In some embodiments, the disclosure includes an isolated antibody or antigen-binding portion thereof that specifically binds to FIXa, comprising a VH CDR1, a VH CDR2, and a VH CDR3 and a VL CDR1, a VL CDR2, and a VL CDR3, wherein the VH CDR1, a VH CDR2, and a VH CDR3 and the VL CDR1, a VL CDR2, and a VL CDR3 are selected from the group consisting of antibodies BIIB-9-408, BIIB-9-416, BIIB-9-629, or BIIB-9-885 in Figure 3B. VH CDR1, VH CDR2 and VH CDR3 and VL CDR1, VL CDR2 and VL CDR3.

[0415] In other embodiments, the present disclosure provides an isolated antibody or antigen-binding portion thereof that specifically binds to FIXa, comprising VH CDR1, VH CDR2 and VH CDR3 and VL CDR1, VL CDR2 and VL CDR3, CDR3 is identified for the following antibodies in Figure 3C: BIIB-9-607, BIIB-9-471, BIIB-9-472, BIIB-9-439, BIIB-9-446, BIIB-9-568, BIIB-9-615, BIIB-9-628, BIIB-9-882, BIIB-9-884, BIIB-9-886, BIIB-9-887, BIIB-9-888, BIIB-9-889, BIIB-9-433, BIIB-9-445, BIIB-9-470, BIIB-9-625, BIIB-9-1264, BIIB-9-1265, BIIB-9-1266, BIIB-9-1267, BIIB-9-1268, BIIB-9-1269, BIIB-9-1261, BIIB-9-1262, BIIB-9-1263, BIIB-9-1264, BIIB-9-1265, BIIB-9-1266, BIIB-9-1267, BIIB-9-1268, BIIB-9-1269 ... the VH CDR1, VH CDR2, and VH CDR3 and the VL CDR1, VL CDR2, and VL CDR3 of an anti-FIXa antibody selected from the group consisting of BIIB-9-1268, BIIB-9-1269, BIIB-9-1270, BIIB-9-1271, BIIB-9-1272, BIIB-9-1273, BIIB-9-1274, BIIB-9-1275, BIIB-9-1276, BIIB-9-1277, BIIB-9-1278, BIIB-9-1279, BIIB-9-1280, BIIB-9-1281, BIIB-9-1282, BIIB-9-1283, BIIB-9-1284, BIIB-9-1285, BIIB-9-1286, and BIIB-9-1287; Contains VL CDR2 and VL CDR3.

[0416] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises VH CDR1, VH CDR2, and VH CDR3 sequences comprising SEQ ID NOs: 800-844, 845-889, and 890-934, respectively (VH CDRs of Class I antibodies), and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NOs: 935-979, 980-1024, and 1025-1069, respectively (VL CDRs of Class I antibodies).

[0417] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises the VH CDR1, VH CDR2, and VH CDR3 sequences (VH CDRs of Class II antibodies) of SEQ ID NOs: 1070-1073, 1074-1077, and 1078-1081, respectively, and / or the VH CDRs of SEQ ID NOs: 1082-1085, 1086, respectively. 1090-1093 (VL CDRs of class II antibodies).

[0418] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises VH CDR1, VH CDR2, and VH CDR3 sequences (VH for Class III antibodies) comprising SEQ ID NOs: 1094-1135, SEQ ID NOs: 1136-1177, and SEQ ID NOs: 1178-1219, respectively. CDR), and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NOs: 1220-1261, 1262-1303 and 1304-1345, respectively (VL CDRs of Class III antibodies).

[0419] In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, VH CDR2 and VH CDR3 sequences comprising SEQ ID NO: 815, SEQ ID NO: 860 and SEQ ID NO: 905, respectively (VH CDRs of the BIIB-9-484 antibody), and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 950, SEQ ID NO: 995 and SEQ ID NO: 1040, respectively (VL CDRs of the BIIB-9-484 antibody).

[0420] In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, VH CDR2 and VH CDR3 sequences comprising SEQ ID NO: 843, SEQ ID NO: 888 and SEQ ID NO: 933, respectively (VH CDRs of the BIIB-9-1335 antibody), and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 950, SEQ ID NO: 995 and SEQ ID NO: 1040, respectively (VL CDRs of the BIIB-9-1335 antibody).

[0421] In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, VH CDR2 and VH CDR3 sequences comprising SEQ ID NO: 844, SEQ ID NO: 889 and SEQ ID NO: 934, respectively (VH CDRs of the BIIB-9-1336 antibody), and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO: 950, SEQ ID NO: 995 and SEQ ID NO: 1040, respectively (VL CDRs of the BIIB-9-1336 antibody).

[0422] In other embodiments, the anti-FIXa antibody or antigen-binding portion thereof cross-competes with and / or binds to the same epitope as antibodies BIIB-9-484, BIIB-9-1335 and BIIB-9-1336. In certain embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises VH CDR1, VH CDR2, and VH CDR3 and VL CDR1, VL CDR2, and VL CDR3, wherein VH CDR3 comprises ARDVGGYAGYYGMDV (SEQ ID NO: 905, BIIB-9-484 VH CDR3), VH CDR2 comprises SISSX1X2SYIYYAX3SVKG (SEQ ID NO: 754), wherein X1 comprises S, G, or any conservative substitution, X2 comprises S, E, or any conservative substitution, and X3 comprises D, E, or any conservative substitution; and VH CDR1 comprises FTFX4SYX5MX 6( X4 comprises S, G or any conservative substitution, X5 comprises D, S or any conservative substitution, and X6 comprises H, N or any conservative substitution. The anti-FIXa antibody or antigen-binding portion thereof can comprise SEQ ID NO: 815 for VH CDR1, SEQ ID NO: 860 for VH CDR2, and SEQ ID NO: 905 for VH CDR3 (BIIB-9-484 VH CDRs).

[0423] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof (a1) VH CDR1, VH CDR2 and VH CDR3 sequences comprising SEQ ID NO: 809, SEQ ID NO: 854 and SEQ ID NO: 899, respectively (for the BIIB-9-440 antibody); VH CDR), and / or VL CDR1, VL CDR2 and VL CDR3 sequences comprising SEQ ID NO:944, SEQ ID NO:989 and SEQ ID NO:1034, respectively (VL CDRs of BIIB-9-440 antibody); (a2) VH CDR1, VH CDR2, and VH CDR3 sequences comprising SEQ ID NO: 1102, SEQ ID NO: 1144, and SEQ ID NO: 1186, respectively (VH CDRs of BIIB-9-882 ​​antibody), and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 1228, SEQ ID NO: 1270, and SEQ ID NO: 1312, respectively (VL CDRs of BIIB-9-882 ​​antibody); (a3) the VH CDR1, VH CDR2, and VH CDR3 sequences comprising SEQ ID NO: 811, SEQ ID NO: 856, and SEQ ID NO: 901, respectively (the VH CDRs of the BIIB-9-460 antibody), and / or the VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 946, SEQ ID NO: 991, and SEQ ID NO: 1036, respectively (the VL CDRs of the BIIB-9-460 antibody); or (a4) VH CDR1, VH CDR2, and VH CDR3 sequences comprising SEQ ID NO: 1108, SEQ ID NO: 1150, and SEQ ID NO: 1192, respectively (VH CDRs of BIIB-9-433 antibody), and / or VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 1234, SEQ ID NO: 1276, and SEQ ID NO: 1318, respectively (VL CDRs of BIIB-9-433 antibody); Includes.

[0424] In some embodiments, the anti-FIXa antibody or antigen-binding portion thereof comprises VH CDR1, VH CDR2 and VH CDR3 sequences (VH CDRs of the BIIB-9-619 antibody) comprising SEQ ID NO: 822, SEQ ID NO: 867 and SEQ ID NO: 912, respectively, and / or VL CDR1, VL CDR2 and VL CDR3 sequences (VL CDRs of the BIIB-9-619 antibody) comprising SEQ ID NO: 957, SEQ ID NO: 1002 and SEQ ID NO: 1047, respectively.

[0425] In some embodiments, an anti-FIXa antibody or antigen-binding portion thereof (i) the VH CDR1, VH CDR2, and VH CDR3 sequences comprising SEQ ID NO: 843, SEQ ID NO: 888, and SEQ ID NO: 933, respectively (the VH CDRs of the BIIB-9-1335 antibody), and / or the VL CDR1, VL CDR2, and VL CDR3 sequences comprising SEQ ID NO: 950, SEQ ID NO: 995, and SEQ ID NO: 1040, respectively (the VL CDRs of the BIIB-9-1335 antibody); or (ii) VH comprising SEQ ID NO: 844, SEQ ID NO: 889, and SEQ ID NO: 934, respectively. CDR1, VH CDR2 and VH CDR3 sequences (VH CDRs of BIIB-9-1336 antibody), and / or VL CDR1, VL CDR2 and VL CDR3 sequences (VL CDRs of BIIB-9-1336 antibody) comprising SEQ ID NO: 950, SEQ ID NO: 995 and SEQ ID NO: 1040, respectively Includes.

[0426] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH, wherein the VH is selected from the group consisting of SEQ ID NOs: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 105, 106, 107, 108, 109, 110, 111, 112, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 07, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149, 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, and 181 (for class I antibodies, SEQ ID NOs: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90 SEQ ID NOs: 5, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, and 89; for class II antibodies, SEQ ID NOs: 91, 93, 95, and 97; and for class III antibodies, SEQ ID NOs: 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 138, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 200, 201, 202, 203, 204, 205, 206, 207, 208, 209, 210, 211, 212, 213, 214, 215, 216, 217, 218, 219, 220, 221, 222, 223, 224, 225 39, 141, 143, 145, 147, 149, 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, and 181), which is at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or about 100% identical to an amino acid sequence selected from the group consisting of:

[0427] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VL, wherein the VL is selected from the group consisting of SEQ ID NOs: 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 295, 297, 299, 301, 303, 305, 307, 309, 311, 313, 315, 317, 319, 321, 323, 325, 327, 329, 331, 333, 335, 337, 339, 341, 343, 345, 347, 349, 351, 353, 355, 357, 359, 361, 363, 365, and 367 (for Class I antibodies, SEQ ID NOs: 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, and 275; for class II antibodies, SEQ ID NOs: 277, 279, 281, and 283; for class III antibodies, SEQ ID NOs: 285, 287, 289, 291, 293, 295, 297, 299, 301, 303, 305, 307, 309, 311, 313, 315, 317, 319, 320, 321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333, 334, 335, 336, 337, 338, 339, 340, 341, 342, 343, 344, 345, 346, 347, 348, 349, 350, 351, 352, 353, 354, 355, 356, 357, 358, 359, 360, 361, 362, 363, 364, 365, 366, 3 321, 323, 325, 327, 329, 331, 333, 335, 337, 339, 341, 343, 345, 347, 349, 351, 353, 355, 357, 359, 361, 363, 365, and 367).

[0428] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein (i) the VH is selected from the group consisting of SEQ ID NOs: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, 89, 91, 93, 95, 97, 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149, 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, and 181 (for class I antibodies, SEQ ID NOs: 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, 87, and 89; for class II antibodies, SEQ ID NOs: 91, 93, 95, and 97; and for class III antibodies, SEQ ID NOs: 99, 101, 103, 105, 107, 109, 111, 113, 115, 117, 119, 121, 123, 125, 127, 129, 131, 133, 135, 137, 139, 141, 143, 145, 147, 149, 151, 153, 155, 157, 159, 161, 163, 165, 167, 169, 171, 173, 175, 177, 179, and 181), comprising an amino acid sequence at least about 70%, at least about 75%, at least about 80%, at least about 85%, at least about 90%, at least about 95%, at least about 96%, at least about 97%, at least about 98%, at least about 99%, or about 100% identical to an amino acid sequence selected from the group consisting of: (ii) VL is selected from the group consisting of SEQ ID NOs: 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227, 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, 275, 277, 279, 281, 283, 285, 287, 289, 291, 293, 295, 297, 298, 299, 300, 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 311, 312, 313, 314, 315, 316, 317, 318, 319, 320, 321, 322, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333, 334, 335, 336, 337, 338, 339, 340, 341, 34 9, 301, 303, 305, 307, 309, 311, 313, 315, 317, 319, 321, 323, 325, 327, 329, 331, 333, 335, 337, 339, 341, 343, 345, 347, 349, 351, 353, 355, 357, 359, 361, 363, 365, and 367 (for Class I antibodies, SEQ ID NOs: 191, 193, 195, 197, 199, 201, 203, 205, 207, 209, 211, 213, 215, 217, 219, 221, 223, 225, 227 , 229, 231, 233, 235, 237, 239, 241, 243, 245, 247, 249, 251, 253, 255, 257, 259, 261, 263, 265, 267, 269, 271, 273, and 275; for class II antibodies, SEQ ID NOs: 277, 279, 281, and 283; for class III antibodies, SEQ ID NOs: 285, 287, 289, 291, 293, 295, 297, 299, 301, 303, 305, 307, 309, 311, 313, 315, 317, 319, 321, 323, 324, 325, 326, 327, 328, 329, 330, 331, 332, 333, 334, 335, 336, 337, 338, 339, 340, 341, 342, 343, 344, 345, 346, 347, 348, 349, 350, 351, 352, 353, 354, 355, 356, 357, 358, 359, 360, 361, 362, 363, 364, 365, 366, 367, 368, 369, 370, 371, 372, 327, 329, 331, 333, 335, 337, 339, 341, 343, 345, 347, 349, 351, 353, 355, 357, 359, 361, 363, 365, and 367).

[0429] In certain aspects, an anti-FIXa antibody comprises a heavy chain variable region from a particular germline heavy chain immunoglobulin gene and / or a light chain variable region from a particular germline light chain immunoglobulin gene. In some embodiments, the VH sequence of the anti-FIXa antibody can be derived from any one of the V, D, or J germline sequences, and / or the VL sequence of the anti-FIXa antibody can be derived from any one of the kappa or lambda germline sequences.

[0430] As demonstrated herein, human antibodies specific for FIXa are produced, which contain heavy chain variable regions that are the product of or derived from human germline genes.Therefore, the present invention provides an isolated FIXa antibody or antigen-binding portion thereof, which contains heavy chain variable regions that are the product of or derived from human VH germline genes selected from the group consisting of VH1-18, VH1-46, VH3-21, VH3-30, VH4-31, VH4-39, VH4-0B, VH5-51, and any combination thereof. In certain embodiments, the VH germline genes are VH1-18.0, VH1-18.1, VH1-18.8, VH1-46.0, VH1-46.4, VH1-46.5, VH1-46.6, VH1-46.7, VH1-46.8, VH1-46.9, VH3-21.0, VH3-23.0, VH3-23.2, VH3-23.6, VH3-30.0, VH4-31. 5, VH4-39.0, VH4-39.5, VH4-0B.4, VH5-51.1, and any combination thereof.

[0431] In another aspect, provided herein is an isolated FIXa antibody, or antigen-binding portion thereof, comprising a heavy chain variable region that is the product of or derived from a human VL germline gene selected from the group consisting of VK1-05, VK1-12, VK1-39, VK2-28, VK3-11, VK3-15, VK3-20, VK4-01, and any combination thereof. In a specific embodiment, the VL germline gene is VK1-05.6, VK1-05.12, VK1-12.0, VK1-12.4, VK1-12.7, VK1-12.10, VK1-12.15, VK1-39.0, VK1-39.3, VK1-39.15, VK2-28.0, VK2-28.1, VK2-28.5, or VK3-11. 0, VK3-11.2, VK3-11.6, VK3-11.14, VK3-15.0, VK3-15.8, VK3-15.10, VK3-20.0, VK3-20.1, VK3-20.4, VK3-20.5, VK4-01.0, VK4-01.4, VK4-01.20, and any combination thereof.

[0432] The antibodies described herein include those that comprise a heavy chain variable region that is the product of, or derived from, one of the human germline VH genes listed above, and those that also comprise a light chain variable region that is the product of, or derived from, one of the human germline VK genes listed above, as shown in the figures.

[0433] As used herein, a human antibody includes heavy and light chain variable regions that are "the product of or derived from" particular germline sequences when the variable regions of the antibody are obtained from a system that uses human germline immunoglobulin genes. Such systems include immunizing transgenic mice harboring human immunoglobulin genes with the antigen of interest or screening human immunoglobulin gene libraries displayed on phage with the antigen of interest. Human antibodies that are "the product of or derived from" human germline immunoglobulin sequences can be identified, for example, by comparing the amino acid sequence of a human antibody with that of a human germline immunoglobulin and selecting the human germline immunoglobulin sequence that is closest in sequence to the sequence of the human antibody (i.e., most percent identical). Human antibodies that are "the product of or derived from" human germline immunoglobulin sequences can contain amino acid differences compared to the germline sequences, for example, due to natural somatic mutations or deliberate introduction of site-directed mutations. However, the selected human antibody will typically have an amino acid sequence that is at least 90% identical to the amino acid sequence encoded by a human germline immunoglobulin gene and contain amino acid residues that identify the human antibody as human when compared to germline immunoglobulin amino acid sequences of other species (e.g., murine germline sequences). In certain cases, a human antibody may have an amino acid sequence that is at least 95% identical, or even at least 96%, 97%, 98%, or 99% identical to the amino acid sequence encoded by the germline immunoglobulin gene. Typically, a human antibody derived from a particular human germline sequence will display no more than 10 amino acid differences from the amino acid sequence encoded by the human germline immunoglobulin gene. In certain cases, a human antibody may display no more than 5 amino acid differences, or even no more than 4, 3, 2, or 1 amino acid differences, from the amino acid sequence encoded by the human germline immunoglobulin gene.

[0434] In some embodiments, the anti-FIXa antibody, or antigen-binding portion thereof, comprises a VH and a VL, wherein (a1) the VH comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 31, and the VL comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 221. contain 96%, at least 97%, at least 98%, at least 99%, or 100% identical amino acid sequences (VH and VL of BIIB-9-484, respectively); (a2) the VH comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 19, and the VL comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identical to SEQ ID NO: 209 (the VH and VL of BIIB-9-440, respectively); (a3) the VH comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 115, and the VL comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identical to SEQ ID NO: 301 (the VH and VL of BIIB-9-882, respectively); (a4) the VH comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 23, and the VL comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identical to SEQ ID NO: 213 (the VH and VL of BIIB-9-460, respectively); (a5) the VH comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or 100% identical to SEQ ID NO: 127, and the VL comprises an amino acid sequence at least 70%, at least 80%, at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identical to SEQ ID NO: 313 (the VH and VL ...

Claims

1. An isolated antibody or antigen-binding portion thereof that binds to activated factor IX (FIXa), wherein the anti-FIXa antibody or antigen-binding portion thereof binds to FIXa with a binding affinity that is greater than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof to FIX zymogen (FIXz), the anti-FIXa antibody or antigen-binding portion thereof comprising a heavy chain variable region (VH) and a light chain variable region (VL), the VH comprising a VH CDR1, a VH CDR2, and a VH CDR3, the VL comprising a VL CDR1, a VL CDR2, and a VL CDR3, the VH CDR1, a VH CDR2, a VH CDR3, a VL CDR1, a VL CDR2, and a VL CDR3, CDR3 is, respectively: (a1) SEQ ID NO: 800, 845, 890, 935, 980, and 1025; (b1) SEQ ID NO: 801, 846, 891, 936, 981, and 1026; (c1) SEQ ID NO: 802, 847, 892, 937, 982, and 1027; (d1) SEQ ID NO: 803, 848, 893, 938, 983, and 1028; (e1) SEQ ID NO: 804, 849, 894, (f1) SEQ ID NOs: 805, 850, 895, 940, 985, and 1030; (g1) SEQ ID NOs: 806, 851, 896, 941, 986, and 1031; (h1) SEQ ID NOs: 807, 852, 897, 942, 987, and 1032; (i1) SEQ ID NOs: 808, 853, 898, 943, 988, and 1033; (j1) SEQ ID NOs: 810, 85 (k1) SEQ ID NOs: 812, 857, 902, 947, 992, and 1037; (l1) SEQ ID NOs: 813, 858, 903, 948, 993, and 1038; (m1) SEQ ID NOs: 814, 859, 904, 949, 994, and 1039; (n1) SEQ ID NOs: 816, 861, 906, 951, 996, and 1041; (o1) SEQ ID NOs: 817, 862, 907, 952, 997, and 1042; (p1) SEQ ID NOs: 818, 863, 908, 953, 998, and 1043; (q1) SEQ ID NOs: 819, 864, 909, 954, 999, and 1044; (r1) SEQ ID NOs: 820, 865, 910, 955, 1000, and 1045; (s1) SEQ ID NOs: 821, 866, 911, 956, 1001, and 1046;(t1) SEQ ID NOs: 823, 868, 913, 958, 1003, and 1048; (u1) SEQ ID NOs: 824, 869, 914, 959, 1004, and 1049; (v1) SEQ ID NOs: 825, 870, 915, 960, 1005, and 1050; (w1) SEQ ID NOs: 826, 871, 916, 961, 1006, and 1051; (x1) SEQ ID NOs: 827, 872, 917, 962, 100; (y1) SEQ ID NOs: 828, 873, 918, 963, 1008, and 1053; (z1) SEQ ID NOs: 829, 874, 919, 964, 1009, and 1054; (a2) SEQ ID NOs: 830, 875, 920, 965, 1010, and 1055; (b2) SEQ ID NOs: 831, 876, 921, 966, 1011, and 1056; (c2) SEQ ID NOs: 832, 877, 922, 967, 1012, and 1057; (d2) SEQ ID NOs: 833, 878, 923, 968, 1013, and 1058; (e2) SEQ ID NO: 83 (f2) SEQ ID NOs: 835, 880, 925, 970, 1015, and 1060; (g2) SEQ ID NOs: 836, 881, 926, 971, 1016, and 1061; (h2) SEQ ID NOs: 837, 882, 927, 972, 1017, and 1062; (i2) SEQ ID NOs: 838, 883, 928, 973, 1018, and 1063; (j2) SEQ ID NOs: 839, 884, 929, 974, 1019, and 1064; (k2) SEQ ID NOs: 840, 885, 930, 975, 1020, and and 1065; (l2) SEQ ID NOs: 841, 886, 931, 976, 1021, and 1066; (m2) SEQ ID NOs: 842, 887, 932, 977, 1022, and 1067; (n2) SEQ ID NOs: 844, 889, 934, 979, 1024, and 1069; (o2) SEQ ID NOs: 1070, 1074, 1078, 1082, 1086, and 1090; (p2) SEQ ID NOs: 1071, 1075, 1079, 1083, 1087, and 1091; (q2) SEQ ID NOs: 1072, 1076, 1080, 1084, 1088, and 1092; (r2 ) SEQ ID NOs: 1073, 1077, 1081, 1085, 1089, and 1093; (s2) SEQ ID NOs: 1094, 1136, 1178, 1220, 1262, and 1304; (t2) SEQ ID NOs: 1095, 1137, 1179, 1221, 1263, and 1305; (u2) SEQ ID NOs: 1096, 1138, 1180, 1222, 1264, and 1306; (v2) SEQ ID NOs: 1097, 1139, 1181, 1223, 1265, and 1307; (w2) SEQ ID NOs: 1098, 1140, 1182, 1224, 1266, and 1308;(x2) SEQ ID NOs: 1099, 1141, 1183, 1225, 1267, and 1309; (y2) SEQ ID NOs: 1100, 1142, 1184, 1226, 1268, and 1310; (z3) SEQ ID NOs: 1101, 1143, 1185, 1227, 1269, and 1311; (a3) ​​SEQ ID NOs: 1103, 1145, 1187, 1229, 1271, and 1313; (b3) SEQ ID NOs: 1104, 1146, 1188, 1230, 1272, and 1314; (c3) SEQ ID NOs: 1105, 1147, 1189, 1231, 1273, and 1315; (d3) SEQ ID NOs: 1106, 1148, 1190, 1232, 1274, and 1316; (e3) SEQ ID NOs: 1107, 1149, 1191, 1233, 1275, and 1317; (f3) SEQ ID NOs: 1109, 1151, 1193, 1235, 1277, and 1319; (g3) SEQ ID NOs: 1110, 1152, 1194, 1236, 1278, and 1320; (h3) SEQ ID NOs: 1111, 1153, 1195, 1237, 1279, and 1321; (i3) SEQ ID NOs: 1112, 1154, 1196, 1238, 1280, and 1322; (j3) SEQ ID NOs: 1113, 1155, 1197, 1239, 1281, and 1323; (k3) SEQ ID NOs: 1114, 1156, 1198, 1240, 1282, and 1324; (l3) SEQ ID NOs: 1115, 1157, 1199, 1241, 1283, and 1325; (m3) SEQ ID NOs: 1116, 1158, 1200, 1242, 1284, and 1326; (n3) SEQ ID NOs: 1117, 1159, 1201, 1243, 1285, and 1327; (o3) SEQ ID NOs: 1118, 1160, 1202, 1244, 1286, and 1328; (p3) SEQ ID NOs: 1119, 1161, 1203, 1245, 1287, and 1329; (q3) SEQ ID NOs: 1120, 1162, 1204, 1246, 1288, and 1330; (r3) SEQ ID NOs: 1121, 1163, 1205, 1247, 1289, and 1331; (s3) SEQ ID NOs: 1122, 1164, 1206, 1248, 1290, and 1332; (t3) SEQ ID NOs: 1123, 1165, 1207, 1249, 1291, and 1333; (u3) SEQ ID NOs: 1124, 1166, 1208, 1250, 1292, and 1334;(v3) SEQ ID NOs: 1125, 1167, 1209, 1251, 1293, and 1335; (w3); (x3) SEQ ID NOs: 1127, 1169, 1211, 1253, 1295, and 1337; (y3) SEQ ID NOs: 1128, 1170, 1212, 1254, 1296, and 1338; (z3) SEQ ID NOs: 1129, 1171, 1213, 1255, 1297, and 1339; (a4) SEQ ID NOs: 1130, 1172, 1214, 1256, 1298, and 1340; (b4) SEQ ID NO: 11 (c4) SEQ ID NOs: 1132, 1174, 1216, 1258, 1300, and 1342; (d4) SEQ ID NOs: 1133, 1175, 1217, 1259, 1301, and 1343; (e4) SEQ ID NOs: 1134, 1176, 1218, 1260, 1302, and 1344; or (f4) SEQ ID NOs: 1135, 1177, 1219, 1261, 1303, and 1345, The VH of (a1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 1, the VH of (b1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 3, the VH of (c1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 5, the VH of (d1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 7, the VH of (e1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 9, the VH of (f1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 11 the VH of (g1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 13; the VH of (h1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 15; the VH of (i1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 17; the VH of (j1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 21; the VH of (k1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 25; the VH of (l1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO:

27. the VH of (m1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:29; the VH of (n1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:33; the VH of (o1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:35; the VH of (p1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:37; the VH of (q1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:39; the VH of (r1) comprises SEQ ID NO: the VH of (s1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 43; the VH of (t1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 47; the VH of (u1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 49; the VH of (v1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 51; the VH of (w1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 53.The VH of (x1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 55, the VH of (y1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 57, the VH of (z1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 59, the VH of (a2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 61, the VH of (b2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 63, the VH of (c2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 65, the VH of (d2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 67 (e2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 69; (f2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 71; (g2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 73; (h2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 75; (i2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 77; (j2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 79; (k2) comprises a VH of SEQ ID NO: 81; the VH of (l2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 83; the VH of (m2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 85; the VH of (n2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 89; the VH of (o2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 91; the VH of (p2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 93; (q2) the VH of (r2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 97; the VH of (s2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 99; the VH of (t2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 101; the VH of (u2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 103; the VH of (v2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 105 The VH of (w2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 107; the VH of (x2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 109; the VH of (y2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 111; the VH of (z2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 113; the VH of (a3) ​​comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 117; the VH of (b3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 119 the VH of (c3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 121; the VH of (d3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 123; the VH of (e3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 125; the VH of (f3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 129; the VH of (g3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 131.The VH of (h3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 133, the VH of (i3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 135, the VH of (j3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 137, the VH of (k3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 139, the VH of (l3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 141, the VH of (m3) comprises an amino acid sequence of SEQ ID NO: 143 the VH of (n3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 145; the VH of (o3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 147; the VH of (p3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 149; the VH of (q3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 151; the VH of (r3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 153; The VH of (s3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 155, the VH of (t3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 157, the VH of (u3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 159, the VH of (v3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 161, the VH of (w3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 163, the VH of (x3) comprises an amino acid sequence of SEQ ID NO: 165 the VH of (y3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 167; the VH of (z3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 169; the VH of (a4) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 171; the VH of (b4) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 173; the VH of (c4) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 175;(d4) VH comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 177; The antibody or antigen-binding portion thereof, wherein the VH of (e4) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 179, or the VH of (f4) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO:

181.

2. An isolated antibody or antigen-binding portion thereof that binds to activated factor IX (FIXa), wherein the anti-FIXa antibody or antigen-binding portion thereof binds to FIXa with a binding affinity that is greater than the binding affinity of the anti-FIXa antibody or antigen-binding portion thereof to FIX zymogen (FIXz), the anti-FIXa antibody or antigen-binding portion thereof comprising a heavy chain variable region (VH) and a light chain variable region (VL), the VH comprising a VH CDR1, a VH CDR2, and a VH CDR3, the VL comprising a VL CDR1, a VL CDR2, and a VL CDR3, the VH CDR1, a VH CDR2, a VH CDR3, a VL CDR1, a VL CDR2, and a VL CDR3, CDR3 is, respectively: (a1) SEQ ID NO: 800, 845, 890, 935, 980, and 1025; (b1) SEQ ID NO: 801, 846, 891, 936, 981, and 1026; (c1) SEQ ID NO: 802, 847, 892, 937, 982, and 1027; (d1) SEQ ID NO: 803, 848, 893, 938, 983, and 1028; (e1) SEQ ID NO: 804, 849, 894, (f1) SEQ ID NOs: 805, 850, 895, 940, 985, and 1030; (g1) SEQ ID NOs: 806, 851, 896, 941, 986, and 1031; (h1) SEQ ID NOs: 807, 852, 897, 942, 987, and 1032; (i1) SEQ ID NOs: 808, 853, 898, 943, 988, and 1033; (j1) SEQ ID NOs: 810, 85 (k1) SEQ ID NOs: 812, 857, 902, 947, 992, and 1037; (l1) SEQ ID NOs: 813, 858, 903, 948, 993, and 1038; (m1) SEQ ID NOs: 814, 859, 904, 949, 994, and 1039; (n1) SEQ ID NOs: 816, 861, 906, 951, 996, and 1041; (o1) SEQ ID NOs: 817, 862, 907, 952, 997, and 1042; (p1) SEQ ID NOs: 818, 863, 908, 953, 998, and 1043; (q1) SEQ ID NOs: 819, 864, 909, 954, 999, and 1044; (r1) SEQ ID NOs: 820, 865, 910, 955, 1000, and 1045; (s1) SEQ ID NOs: 821, 866, 911, 956, 1001, and 1046;(t1) SEQ ID NOs: 823, 868, 913, 958, 1003, and 1048; (u1) SEQ ID NOs: 824, 869, 914, 959, 1004, and 1049; (v1) SEQ ID NOs: 825, 870, 915, 960, 1005, and 1050; (w1) SEQ ID NOs: 826, 871, 916, 961, 1006, and 1051; (x1) SEQ ID NOs: 827, 872, 917, 962, 1007, and 1052; (y1) SEQ ID NOs: 828, 873, 918, 963, 1008, and 1053; (z1) SEQ ID NOs: 829, 874, 919, 964, 1009, and 1054; (a2) SEQ ID NOs: 830, 875, 920, 965, 1010, and 1055; (b2) SEQ ID NOs: 831, 876, 921, 966, 1011, and 1056; (c2) SEQ ID NOs: 832, 877, 922, 967, 1012, and 1057; (d2) SEQ ID NOs: 833, 878, 923, 968, 1013, and 1058; (e2) SEQ ID NOs: 834, 879, 924, 9 (f2) SEQ ID NOs: 835, 880, 925, 970, 1015, and 1060; (g2) SEQ ID NOs: 836, 881, 926, 971, 1016, and 1061; (h2) SEQ ID NOs: 837, 882, 927, 972, 1017, and 1062; (i2) SEQ ID NOs: 838, 883, 928, 973, 1018, and 1063; (j2) SEQ ID NOs: 839, 884, 929, 974, 1019, and 1064; (k2) SEQ ID NOs: 840, 8 85, 930, 975, 1020, and 1065; (l2) SEQ ID NOs: 841, 886, 931, 976, 1021, and 1066; (m2) SEQ ID NOs: 842, 887, 932, 977, 1022, and 1067; (n2) SEQ ID NOs: 1070, 1074, 1078, 1082, 1086, and 1090; (o2) SEQ ID NOs: 1071, 1075, 1079, 1083, 1087, and 1091; (p2) SEQ ID NOs: 1072, 1076, 1080, 1084, 1088,; and 1092; (q2) SEQ ID NOs: 1073, 1077, 1081, 1085, 1089, and 1093; (r2) SEQ ID NOs: 1094, 1136, 1178, 1220, 1262, and 1304; (s2) SEQ ID NOs: 1095, 1137, 1179, 1221, 1263, and 1305; (t2) SEQ ID NOs: 1096, 1138, 1180, 1222, 1264, and 1306; (u2) SEQ ID NOs: 1097, 1139, 1181, 1223, 1265, and 1307; (v2) SEQ ID NOs: 1098, 1140, 1182, 1224, 1266, and and 1308; (w2) SEQ ID NOs: 1099, 1141, 1183, 1225, 1267, and 1309; (x2) SEQ ID NOs: 1100, 1142, 1184, 1226, 1268, and 1310; (y2) SEQ ID NOs: 1101, 1143, 1185, 1227, 1269, and 1311; (z2) SEQ ID NOs: 1103, 1145, 1187, 1229, 1271, and 1313; (a3) ​​SEQ ID NOs: 1104, 1146, 1188, 1230, 1272, and 1314; (b3) SEQ ID NOs: 1105, 1147, 1189, 1231, 1273, and 1 315; (c3) SEQ ID NOs: 1106, 1148, 1190, 1232, 1274, and 1316; (d3) SEQ ID NOs: 1107, 1149, 1191, 1233, 1275, and 1317; (e3) SEQ ID NOs: 1109, 1151, 1193, 1235, 1277, and 1319; (f3) SEQ ID NOs: 1110, 1152, 1194, 1236, 1278, and 1320; (g3) SEQ ID NOs: 1111, 1153, 1195, 1237, 1279, and 1321; (h3) SEQ ID NOs: 1112, 1154, 1196, 1238, 1280, and 132 2; (i3) SEQ ID NOs: 1113, 1155, 1197, 1239, 1281, and 1323; (j3) SEQ ID NOs: 1114, 1156, 1198, 1240, 1282, and 1324; (k3) SEQ ID NOs: 1115, 1157, 1199, 1241, 1283, and 1325; (l3) SEQ ID NOs: 1116, 1158, 1200, 1242, 1284, and 1326; (m3) SEQ ID NOs: 1117, 1159, 1201, 1243, 1285, and 1327; (n3) SEQ ID NOs: 1118, 1160, 1202, 1244, 1286, and 1328;(o3) SEQ ID NOs: 1119, 1161, 1203, 1245, 1287, and 1329; (p3) SEQ ID NOs: 1120, 1162, 1204, 1246, 1288, and 1330; (q3) SEQ ID NOs: 1121, 1163, 1205, 1247, 1289, and 1331; (r3) SEQ ID NOs: 1122, 1164, 1206, 1248, 1290, and 1332; (s3) SEQ ID NO: 112 (t3) SEQ ID NOs: 1124, 1166, 1208, 1250, 1292, and 1334; (u3) SEQ ID NOs: 1125, 1167, 1209, 1251, 1293, and 1335; (v3) SEQ ID NOs: 1126, 1168, 1210, 1252, 1294, and 1336; (w3) SEQ ID NOs: 1127, 1169, 1211 , 1253, 1295, and 1337; (x3) SEQ ID NOs: 1128, 1170, 1212, 1254, 1296, and 1338; (y3) SEQ ID NOs: 1129, 1171, 1213, 1255, 1297, and 1339; (z3) SEQ ID NOs: 1130, 1172, 1214, 1256, 1298, and 1340; (a4) SEQ ID NOs: 1131, 1173, 1215, 1257, 1299, and 1341; (b4) SEQ ID NOs: 1132, 1174, 1216, 1258, 1300, and 1342; (c4) SEQ ID NOs: 1133, 1175, 1217, 1259, 1301, and 1343; (d4) SEQ ID NOs: 1134, 1176, 1218, 1260, 1302, and 1344; or (e4) SEQ ID NOs: 1135, 1177, 1219, 1261, 1303, and 1345; comprising the amino acid sequence shown in The VL of (a1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 191, the VL of (b1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO: 193, and the VL of (c1) comprises an amino acid sequence that is at least 80% identical to the amino acid sequence of SEQ ID NO:

195. The VL of (d1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 197; the VL of (e1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 199; the VL of (f1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 201 The VL of (g1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 203; the VL of (h1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 205; the VL of (i1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 207; the VL of (j1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 211; the VL of (k1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 215; The VL of (l1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 217, the VL of (m1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 219, the VL of (n1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 223, the VL of (o1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 225, the VL of (p1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 227, the VL of (q1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 229 % identical to the amino acid sequence of SEQ ID NO: 231; the VL of (s1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 233; the VL of (t1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 237; the VL of (u1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 239; the VL of (v1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 241; the VL of (w1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 243 the VL of (x1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 245; the VL of (y1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 247; the VL of (z1) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 249; the VL of (a2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 251; the VL of (b2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 253;The VL of (c2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 255, the VL of (d2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 257, the VL of (e2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 259, the VL of (f2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 261, the VL of (g2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 263, the VL of (h2) comprises an amino acid sequence of SEQ ID NO: 265 (i2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 267; (j2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 269; (k2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 271; (l2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 273; (m2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 275; The VL of (n2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 277, the VL of (o2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 279, the VL of (p2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 281, the VL of (q2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 283, the VL of (r2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 285, the VL of (s2) comprises an amino acid sequence of SEQ ID NO: 287 the VL of (t2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 289; the VL of (u2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 291; the VL of (v2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 293; the VL of (w2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 295; the VL of (x2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 297;(y2) VL is an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 299; the VL of (z2) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 303; the VL of (a3) ​​comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 305; the VL of (b3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 307; the VL of (c3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 309; the VL of (d3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 311; the VL of (e3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 315 the VL of (f3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 317; the VL of (g3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 319; the VL of (h3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 321; the VL of (i3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 323; the VL of (j3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 325 (k3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 327; (l3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 329; (m3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 331; (n3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 333; (o3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 335; (p3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 337 the VL of (q3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 339; the VL of (r3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 341; the VL of (s3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 343; the VL of (t3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 345; the VL of (u3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 347;The VL of (v3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 349, the VL of (w3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 351, the VL of (x3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 353, the VL of (y3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 355, the VL of (z3) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 357, the VL of (a4) is the VL of (b4) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 361; the VL of (c4) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 363; the VL of (d4) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 365; or the VL of (e4) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

367.

3. 3. A bispecific molecule comprising the antibody or antigen-binding portion thereof of claim 1 or 2 and an antibody or antigen-binding portion thereof that binds to factor X zymogen (FXz), wherein the anti-FXz antibody or antigen-binding portion thereof comprises a VH and a VL, wherein the VH comprises a VH CDR1, a VH CDR2, and a VH CDR3, and the VL comprises a VL CDR1, a VL CDR2, and a VL CDR3, and wherein the anti-FXz antibody or antigen-binding portion thereof comprises: (a) SEQ ID NOs: 1370, 1460, 1550, 1640, 1730, and 1820, respectively; (b) SEQ ID NOs: 1371, 1461, 1551, 1641, 1731, and 1821, respectively; (c) SEQ ID NOs: 1372, 1462, 1552, 1642, 1732, and 1822, respectively; (d) SEQ ID NOs: 1373, 1463, 1553, 1643, 1733, and １８２３； (e) SEQ ID NOs: 1374, 1464, 1554, 1644, 1734, and 1824, respectively; (f) SEQ ID NOs: 1375, 1465, 1555, 1645, 1735, and 1825, respectively; (g) SEQ ID NOs: 1376, 1466, 1556, 1646, 1736, and 1826, respectively; (h) SEQ ID NOs: 1377, 1467, 1557, 1647, 1737, and 1827, respectively; (i) SEQ ID NOs: 1378, 1468, 1558, 1648, 1738, and 1828, respectively; (j) SEQ ID NOs: 1379, 1469, 1559, 1649, 1739, and 1829, respectively; (k) SEQ ID NOs: 1380, 1470, 1560, 1650, 1740, and 1830, respectively; (l) SEQ ID NOs: 1381, 1471, 1561, 1651, 1741, and 1831, respectively; (m) SEQ ID NOs: 1382, 1472, 1562, 1652, 1742, and 1832, respectively; (n) SEQ ID NOs: 1383, 1473, 1563, 1653, 1743, and 1833, respectively; (o) SEQ ID NOs: 1384, 1474, 1564, 1654, 1744, and 1834, respectively; (p) SEQ ID NOs: 1385, 1475, 1565, 1655, 1745, and 1835, respectively; (q) SEQ ID NOs: 1386, 1476, 1566, 1656, 1746, and 1836, respectively; (r) SEQ ID NOs: 1387, 1477, 1567, 1657, 1747, and 1837, respectively; (s) SEQ ID NOs: 1388, 1478, 1568, 1658, 1748, and 1838, respectively; (t) SEQ ID NOs: 1389, 1479, 1569, 1659, 1749, and 1839, respectively; (u) SEQ ID NOs: 1390, 1480, 1570, 1660, 1750, and 1840, respectively; (v) SEQ ID NOs: 1391, 1481, 1571, 1661, 1751, and 1841, respectively; (w) SEQ ID NOs: 1392, 1482, 1572, 1662, 1752, and 1842, respectively; (x) SEQ ID NOs: 1393, 1483, 1573, 1663, 1753, and 1843, respectively; (y) SEQ ID NOs: 1394, 1484, 1574, 1664, 1754, and 1844, respectively; (z) SEQ ID NOs: 1395, 1485, 1575, 1665, 1755, and 1845, respectively; (aa) SEQ ID NOs: 1396, 1486, 1576, 1666, 1756, and 1846, respectively; (bb) SEQ ID NOs: 1397, 1487, 1577, 1667, 1757, and 1847, respectively; (cc) SEQ ID NOs: 1398, 1488, 1578, 1668, 1758, and Bi 1848; (dd) SEQ ID NOs: 1399, 1489, 1579, 1669, 1759, and 1849, respectively; (ee) SEQ ID NOs: 1400, 1490, 1580, 1670, 1760, and 1850, respectively; (ff) SEQ ID NOs: 1401, 1491, 1581, 1671, 1761, and 1851, respectively; (gg) SEQ ID NOs: 1402, 1492, 1582, 1672, 1762, and 1852, respectively; (hh) SEQ ID NOs: 1403, 1493, 1583, 1673, 1763, and 1853, respectively; (ii) SEQ ID NOs: 1404, 1494, 1584, 1674, 1764, and 1854, respectively; (jj) SEQ ID NOs: 1405, 1495, 1585, 1675, 1765, and 1855, respectively; (kk) SEQ ID NOs: 1406, 1496, 1586, 1676, 1766, and 1856, respectively; (ll) SEQ ID NOs: 1407, 1497, 1587, 1677, 1767, and 1857, respectively; (mm) SEQ ID NOs: 1408, 1498, 1588, 1678, 1768, and 1858, respectively; (nn) SEQ ID NOs: 1409, 1499, 1589, 1679, 1769, and 1859, respectively; (oo) SEQ ID NOs: 1410, 1500, 1590, 1680, 1770, and 1860, respectively; (pp) SEQ ID NOs: 1411, 1501, 1591, 1681, 1771, and 1861, respectively; (qq) SEQ ID NOs: 1412, 1502, 1592, 1682, 1772, and 1862, respectively; (rr) SEQ ID NOs: 1413, 1503, 1593, 1683, 1773, and 1863, respectively; (ss) SEQ ID NOs: 1414, 1504, 1594, 1684, 1774, and 1864, respectively; (tt) SEQ ID NOs: 1415, 1505, 1595, 1685, 1775, and 1865, respectively; (uu) SEQ ID NOs: 1416, 1506, 1596, 1686, 1776, and 1866, respectively; (vv) SEQ ID NOs: 1417, 1507, 1597, 1687, 1777, and 1867, respectively; (ww) SEQ ID NOs: 1418, 1508, 1598, 1688, 1778, and 1868, respectively; (xx) SEQ ID NOs: 1419, 1509, 1599, 1689, 1779, and 1869, respectively; (yy) SEQ ID NOs: 1420, 1510, 1600, 1690, 1780, and 1870, respectively; (zz) SEQ ID NOs: 1421, 1511, 1601, 1691, 1781, and 1871, respectively; (aaa) SEQ ID NOs: 1422, 1512, 1602, 1692, 1782, and 1872, respectively; (bbb) SEQ ID NOs: 1423, 1513, 1603, 1693, 1783, and and 1873; (ccc) SEQ ID NOs: 1424, 1514, 1604, 1694, 1784, and 1874, respectively; (ddd) SEQ ID NOs: 1425, 1515, 1605, 1695, 1785, and 1875, respectively; (eee) SEQ ID NOs: 1426, 1516, 1606, 1696, 1786, and 1876, respectively; (fff) SEQ ID NOs: 1427, 1517, 1607, 1697, 1787, and 1877, respectively; (ggg) SEQ ID NOs: 1428, 1518, 1608, 1698, 1788, and 1878, respectively; (hhh) SEQ ID NOs: 1429, 1519, 1609, 1699, 1789, and 1879, respectively; (iii) SEQ ID NOs: 1430, 1520, 1610, 1700, 1790, and 1880, respectively; (jjj) SEQ ID NOs: 1431, 1521, 1611, 1701, 1791, and 1881, respectively; (kkk) SEQ ID NOs: 1432, 1522, 1612, 1702, 1792, and 1882, respectively; (lll) SEQ ID NOs: 1433, 1523, 1613, 1703, 1793, and 1883, respectively; (mmm) SEQ ID NOs: 1434, 1524, 1614, 1704, 1794, and 1884, respectively; (nnn) SEQ ID NOs: 1435, 1525, 1615, 1705, 1795, and 1885, respectively; (ooo) SEQ ID NOs: 1436, 1526, 1616, 1706, 1796, and 1886, respectively; (ppp) SEQ ID NOs: 1437, 1527, 1617, 1707, 1797, and 1887, respectively; (qqq) SEQ ID NOs: 1438, 1528, 1618, 1708, 1798, and 1888, respectively; (rrr) SEQ ID NOs: 1439, 1529, 1619, 1709, 1799, and 1889, respectively; (sss) SEQ ID NOs: 1440, 1530, 1620, 1710, 1800, and 1890, respectively; (ttt) SEQ ID NOs: 1441, 1531, 1621, 1711, 1801, and 1891, respectively; (uuu) SEQ ID NOs: 1442, 1532, 1622, 1712, 1802, and 1892, respectively; (vvv) SEQ ID NOs: 1443, 1533, 1623, 1713, 1803, and 1893, respectively; (www) SEQ ID NOs: 1444, 1534, 1624, 1714, 1804, and 1894, respectively; (xxx) SEQ ID NOs: 1445, 1535, 1625, 1715, 1805, and 1895, respectively; (yyy) SEQ ID NOs: 1446, 1536, 1626, 1716, 1806, and 1896, respectively; (zzz) SEQ ID NOs: 1447, 1537, 1627, 1717, 1807, and 1897, respectively; (aaaa) SEQ ID NOs: 1448, 1538, 1628, 1718, 1808, and 1898; (bbbb) SEQ ID NOs: 1449, 1539, 1629, 1719, 1809, and 1899, respectively; (cccc) SEQ ID NOs: 1450, 1540, 1630, 1720, 1810, and 1900, respectively; (dddd) SEQ ID NOs: 1451, 1541, 1631, 1721, 1811, and 1901, respectively; (eeee) SEQ ID NOs: 1452, 1542, 1632, 1722, 1812, and 1902, respectively; (ffff) SEQ ID NOs: 1453, 1543, 1633, 1723, 1813, and 1903, respectively; (gggg) SEQ ID NOs: 1454, 1544, 1634, 1724, 1814, and 1904, respectively; (hhhh) SEQ ID NOs: 1455, 1545, 1635, 1725, 1815, and 1905, respectively; (iii) SEQ ID NOs: 1456, 1546, 1636, 1726, 1816, and 1906, respectively; (jjjj) SEQ ID NOs: 1457, 1547, 1637, 1727, 1817, and 1907, respectively; (kkkk) SEQ ID NOs: 1458, 1548, 1638, 1728, 1818, and 1908, respectively; or (llll) SEQ ID NOs: 1459, 1549, 1639, 1729, 1819, and 1909, respectively. and a VH CDR1, a VH CDR2, a VH CDR3, a VL CDR1, a VL CDR2, and a VL CDR3 comprising (a) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 377; (b) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 379; (c) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 381; (d) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 383; (e) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 385; (f) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

387. (g) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 389; (h) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 391; (i) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 393; (j) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 395; (k) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 397; and (l) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

399. (m) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 401; (n) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 403; (o) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 405; (p) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 407; (q) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 409; (r) the VH comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

411. the VH of (s) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 413; the VH of (t) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 415; the VH of (u) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 417; the VH of (v) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 419; the VH of (w) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 421; the VH of (x) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 422; the VH of (y) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 425; the VH of (z) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 427; the VH of (aa) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 429; the VH of (bb) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 431; and the VH of (cc) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

433. (dd) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 435; (ee) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 437; (ff) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 439; (gg) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 441; (hh) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 443; (ii) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 445 the VH of (jj) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 447; the VH of (kk) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 449; the VH of (ll) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 451; the VH of (mm) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 453; the VH of (nn) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 455; the VH of (oo) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 45 7, the VH of (pp) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 459, the VH of (qq) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 461, the VH of (rr) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 463, the VH of (ss) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 465, and the VH of (tt) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 467.The VH of (uu) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 469, the VH of (vv) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 471, the VH of (ww) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 473, the VH of (xx) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 475, the VH of (yy) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 477, and the VH of (zz) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

479. the VH of (aaa) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 481; the VH of (bbb) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 483; the VH of (ccc) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 485; the VH of (ddd) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 487; the VH of (eee) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 489; (f) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 491; (ggg) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 493; (hhh) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 495; (iii) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 497; (jjj) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 499; the VH of (lll) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 503; the VH of (mmm) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 505; the VH of (nnn) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 507; the VH of (ooo) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 509; the VH of (ppp) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 511;(qqq) VH of SEQ ID NO: 513, the VH of (rrr) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:5115; the VH of (sss) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:517; the VH of (ttt) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:519; the VH of (uuu) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:521; the VH of (vvv) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:523 the VH of (www) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:525; the VH of (xxx) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:527; the VH of (yyy) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:529; the VH of (zzz) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:531; the VH of (aaaa) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:533; the VH of (bbbb) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:535 the VH of (cccc) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:537; the VH of (dddd) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:539; the VH of (eeee) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:541; the VH of (ffff) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:543; the VH of (gggg) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:545 the VH of (hhhh) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 547; the VH of (iii) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 549; the VH of (jjjj) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 551; the VH of (kkkk) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 553; or the VH of (llll) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

555.

4. (a) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:565; (b) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:567; (c) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:569; (d) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:571; (e) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:573; and (f) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

575. (g) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 577; (h) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 579; (i) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 581; (j) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 583; (k) the VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 585; (m) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:589; (n) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:591; (o) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:593; (p) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:595; (q) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:597 the VL of (r) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:599; the VL of (s) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:601; the VL of (t) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:603; the VL of (u) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:605; the VL of (v) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:607; the VL of (w) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:60 9, the VL of (x) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 611, the VL of (y) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 613, the VL of (z) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 615, the VL of (aa) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 617, the VL of (bb) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 619, The VL of (cc) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 621, the VL of (dd) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 623, the VL of (ee) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 625, the VL of (ff) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 627, the VL of (gg) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 629, the VL of (hh) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 631 % identical to the amino acid sequence of SEQ ID NO:633; the VL of (ii) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:633; the VL of (jj) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:635; the VL of (kk) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:637; the VL of (ll) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:639; the VL of (mm) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:641; the VL of (nn) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:643 the VL of (oo) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 645; the VL of (pp) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 647; the VL of (qq) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 649; the VL of (rr) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 651; the VL of (ss) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 653;The VL of (tt) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 655, the VL of (uu) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 657, the VL of (vv) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 659, the VL of (ww) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 661, the VL of (xx) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 663, the VL of (yy) comprises at least an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

665. the VL of (zz) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 667; the VL of (aaa) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 669; the VL of (bbb) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 671; the VL of (ccc) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 673; the VL of (ddd) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 675; The VL of (e) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 677, the VL of (fff) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 679, the VL of (ggg) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 681, the VL of (hhh) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 683, the VL of (iii) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 685, the VL of (jjj) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 687 The VL of (kkk) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 689, the VL of (lll) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 691, the VL of (mmm) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 693, the VL of (nnn) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 695, the VL of (ooo) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 697,(ppp) VL is the amino acid sequence of SEQ ID NO: 699; the VL of (qqq) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 701; the VL of (rrr) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 703; the VL of (sss) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 705; the VL of (ttt) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 707; the VL of (uuu) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 709 wherein the VL of (vvv) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 711; the VL of (www) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 713; the VL of (xxx) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 715; the VL of (yyy) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 717; the VL of (zzz) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 719; the VL of (aaaa) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 72 1, the VL of (bbbb) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 723, the VL of (cccc) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 725, the VL of (dddd) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 727, the VL of (eeee) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 729, the VL of (ffff) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 731 the VL of (gggg) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 733; the VL of (hhhh) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 735; the VL of (iii) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 737; the VL of (jjjj) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 739; the VL of (kkkk) comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO: 741;or (III) VL comprises an amino acid sequence at least 80% identical to the amino acid sequence of SEQ ID NO:

743.

5. A nucleic acid encoding an antibody or antigen-binding portion thereof according to claim 1 or 2, or a bispecific molecule according to claim 3 or 4.

6. A pharmaceutical composition comprising an antibody or antigen-binding portion thereof according to claim 1 or 2, or a bispecific molecule according to claim 3 or 4, and a pharma- ceutically acceptable carrier.

7. 10. An antibody or antigen-binding portion thereof according to claim 1 or 2, a bispecific molecule according to claim 3 or 4, or a pharmaceutical composition according to claim 6, for use in therapy.

8. 10. A bispecific molecule according to claim 3 or 4, or a pharmaceutical composition according to claim 6, for use in treating a patient with hemophilia A.

Citation Information

Patent Citations

  • Bispecific antibody substituting for functional protein

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