HER3 antigen-binding molecules

Abstract

To provide HER3 antigen-binding molecules, nucleic acids and expression vectors encoding the HER3 antigen-binding molecules, compositions comprising the HER3 antigen-binding molecules, and methods using the HER3 antigen-binding molecules.SOLUTION: In a first aspect, the present invention provides an antigen-binding molecule, optionally isolated, which is capable of binding to HER3 in extracellular region subdomain II. In some embodiments, the antigen-binding molecule inhibits interaction between HER3 and an interaction partner for HER3. In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising or consisting of a specific amino acid sequence. The present invention also provides an antigen-binding molecule, optionally isolated, comprising (i) an antigen-binding molecule according to the present invention, and (ii) an antigen-binding molecule capable of binding to an antigen other than HER3.SELECTED DRAWING: Figure 1A

Description

[Technical Field]

[0001] This application claims priority from PCT / EP2018 / 058259, filed March 29, 2018, and US 16 / 170,370, filed October 25, 2018, the contents and elements of which are incorporated herein by reference in their entirety and for all purposes. FIELD OF THE INVENTION The present invention relates to the field of molecular biology, more particularly to the field of antibody technology. The present invention also relates to methods of medical treatment and prophylaxis. [Background technology]

[0002] Increased HER3 expression is associated with poor prognosis in multiple solid tumors, including breast, gastric, head and neck, pancreatic, ovarian, and lung cancers. HER3-mediated signaling has adverse consequences for tumor progression; upregulation of HER3 is associated with resistance to anti-HER2 and anti-EGFR therapy; solid tumors refractory to anti-PD-1 therapy have been shown to express HER3 at higher levels compared with those that respond to anti-PD-1 therapy.

[0003] HER3-binding antibodies are described, for example, in Zhang et al., Acta Biochimica et Biophysica Sinica (2016), 48(1):39-48. The anti-HER3 antibody, LJM-716, binds to epitopes on subdomains II and IV of the HER3 extracellular domain, locking HER3 in an inactive conformation (Garner et al., Cancer Res (2013), 73:6024-6035). MM-121 (also known as seribantumab) has been shown to inhibit HER3-mediated signaling by blocking the binding of heregulin (HRG) to HER3 (Schoeberl et al., Sci. Signal. (2009), 2(77):ra31). Patritumab (also known as U-1287 and AMG-888) also blocks heregulin binding to HER3 (see, e.g., Shimizu et al., Cancer Chemother Pharmacol. (2017), 79(3):489-495). RG7116 (also known as lumletuzumab and RO-5479599) recognizes an epitope within subdomain I of the HER3 extracellular domain (see, e.g., Mirschberger et al., Cancer Research (2013), 73(16)5183-5194). KTN3379 binds to HER3 through interactions with amino acid residues in subdomain III (corresponding to the following position 1 of SEQ ID NO: Gly476, Pro477, Arg481, Gly452, Arg475, Ser450, Gly420, Ala451, Gly419, Arg421, Thr394, Leu423, Arg426, Gly427, Lys356, Leu358, Leu358, Lys356, Ala330, Lys329, and Gly337) and Met310, Glu311, and Pro328 in subdomain II (see Lee et al., Proc Natl Acad Sci USA. 2015 Oct. 27, 112(43):3225).AV-203 (also known as CAN-017) has been shown to block NRG1 binding to HER3 and promote HER3 degradation (see Meetze et al., Eur J Cancer, 2012, 48:126). REGN1400 also inhibits ligand binding to HER3 (see Zhang et al., Mol Cancer Ther (2014), 13:1345-1355). RG7597 (durigotuzumab) is a dual-acting Fab (DAF) capable of binding to both HER3 and EGFR, and binds to subdomain III of HER3. (See Schaefer et al., Cancer Cell (2011), 20(4):472-486.) MM-111 and MM-141 are bispecific antibodies with a HER3-binding arm that inhibit the binding of HRG ligands to HER3 (See McDonagh et al., Mol Cancer Ther (2012), 11:582-593; and Fitzgerald et al., Mol Cancer Ther (2014), 13:410-425.) Summary of the Invention [Means for solving the problem]

[0004] In a first aspect, the present invention provides an antigen-binding molecule, optionally an isolated antigen-binding molecule, capable of binding to HER3 within the extracellular region subdomain II.

[0005] In some embodiments, the antigen binding molecule inhibits the interaction of HER3 with an interaction partner of HER3.

[0006] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO:16.

[0007] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO:229.

[0008] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NOs: 230 and 231.

[0009] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO:230.

[0010] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO:231.

[0011] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO:23.

[0012] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO:21.

[0013] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 43 HC-CDR2 having the amino acid sequence of SEQ ID NO: 46 HC-CDR3 having the amino acid sequence of SEQ ID NO: 51 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 91 LC-CDR2 having the amino acid sequence of SEQ ID NO: 94 LC-CDR3 having the amino acid sequence of SEQ ID NO: 99 The light chain variable (VL) region comprises:

[0014] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 The light chain variable (VL) region comprises:

[0015] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 89 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 The light chain variable (VL) region comprises:

[0016] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 90 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 96 The light chain variable (VL) region comprises:

[0017] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 98 The light chain variable (VL) region comprises:

[0018] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 The light chain variable (VL) region comprises:

[0019] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 49 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 The light chain variable (VL) region comprises:

[0020] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 50 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 The light chain variable (VL) region comprises:

[0021] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 The light chain variable (VL) region comprises:

[0022] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 97 The light chain variable (VL) region comprises:

[0023] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 42 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 The light chain variable (VL) region comprises:

[0024] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 158 HC-CDR2 having the amino acid sequence of SEQ ID NO: 159 HC-CDR3 having the amino acid sequence of SEQ ID NO: 160 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 165 LC-CDR2 having the amino acid sequence of SEQ ID NO: 166 LC-CDR3 having the amino acid sequence of SEQ ID NO: 167 The light chain variable (VL) region comprises:

[0025] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO:22.

[0026] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 128 HC-CDR2 having the amino acid sequence of SEQ ID NO: 129 HC-CDR3 having the amino acid sequence of SEQ ID NO: 130 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 136 LC-CDR2 having the amino acid sequence of SEQ ID NO: 137 LC-CDR3 having the amino acid sequence of SEQ ID NO: 138 The light chain variable (VL) region comprises:

[0027] In some embodiments, the antigen-binding molecule is (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 144 HC-CDR2 having the amino acid sequence of SEQ ID NO: 145 HC-CDR3 having the amino acid sequence of SEQ ID NO: 146 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 151 LC-CDR2 having the amino acid sequence of SEQ ID NO: 152 LC-CDR3 having the amino acid sequence of SEQ ID NO: 153 The light chain variable (VL) region comprises:

[0028] In certain embodiments, the antigen-binding molecule comprises: (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 a light chain variable (VL) region incorporating; or (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 97 a light chain variable (VL) region incorporating; or (i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 42 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 The light chain variable (VL) region comprises:

[0029] In some embodiments, the antigen-binding molecule is (i) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 24; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 74; or (ii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 25; and Has at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 75 VL region containing the amino acid sequence; or (iii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 26; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 76; or (iv) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 27; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 77; or (v) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 28; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (vi) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 29; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (vii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 30; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (viii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 31; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 79; or (ix) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 32; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 79; or (x) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 33; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 80; or (xi) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 34; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 81; or (xii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 35; and Has at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 82 VL region containing the amino acid sequence; or (xiii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 36; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 83; or (xiv) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 37; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 84; or (xv) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 38; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 85; or (xvi) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 39; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 86; or (xvii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 40; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 87; or (xviii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 127; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 135; or (xix) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 143; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 150; or (xx) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 157; and It comprises a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 164.

[0030] In certain embodiments, the antigen-binding molecule comprises: (i) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 36; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 83; or (ii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 37; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 84; or (iii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 38; and It comprises a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO:85.

[0031] In some embodiments, the antigen-binding molecule is capable of binding to human HER3, and one or more of mouse HER3, rat HER3, and cynomolgus monkey HER3.

[0032] Also provided are antigen-binding molecules, optionally isolated antigen-binding molecules, including (i) antigen-binding molecules according to the invention, and (ii) antigen-binding molecules capable of binding to antigens other than HER3.

[0033] In some embodiments, the antigen-binding molecule is capable of binding to the cell surface of a cell that expresses HER3.

[0034] In some embodiments, the antigen binding molecule is capable of inhibiting HER3-mediated signaling.

[0035] In some embodiments, the antigen-binding molecule comprises an Fc region, wherein the Fc region comprises a polypeptide having one or more of: (i) a C at a position corresponding to 242 and a C at a position corresponding to 334, and (ii) an A at a position corresponding to 236, a D at a position corresponding to 239, an E at a position corresponding to 332, an L at a position corresponding to 330, a K at a position corresponding to 345, and a G at a position corresponding to 430. In some embodiments, the Fc region comprises a polypeptide having a C at a position corresponding to 242, a C at a position corresponding to 334, an A at a position corresponding to 236, a D at a position corresponding to 239, an E at a position corresponding to 332, and an L at a position corresponding to 330.

[0036] Also provided is a chimeric antigen receptor (CAR) comprising an antigen-binding molecule according to the invention.

[0037] Also provided is a nucleic acid or nucleic acids, optionally isolated nucleic acids, encoding an antigen-binding molecule or CAR in accordance with the invention.

[0038] Also provided is an expression vector or vectors comprising a nucleic acid or nucleic acids in accordance with the invention.

[0039] Also provided are cells comprising an antigen-binding molecule, a CAR, a nucleic acid or nucleic acids, or an expression vector or expression vectors in accordance with the invention.

[0040] Also provided are methods comprising culturing a cell comprising a nucleic acid or nucleic acids, or an expression vector or vectors according to the invention, under conditions suitable for expression of the antigen-binding molecule or CAR from the nucleic acid(s) or expression vector(s).

[0041] Also provided are compositions comprising an antigen-binding molecule, a CAR, a nucleic acid or nucleic acids, an expression vector or expression vectors, or a cell according to the invention.

[0042] Also provided is an antigen-binding molecule, a CAR, a nucleic acid or nucleic acids, an expression vector or vectors, a cell, or a composition in accordance with the invention for use in a method of medical treatment or prophylaxis.

[0043] Also provided is an antigen-binding molecule, a CAR, a nucleic acid or nucleic acids, an expression vector or vectors, a cell, or a composition in accordance with the invention for use in a method of treating or preventing cancer.

[0044] Also provided is the use of an antigen-binding molecule, a CAR, a nucleic acid or nucleic acids, an expression vector or vectors, a cell, or a composition according to the invention in the manufacture of a medicament for use in a method of treating or preventing cancer.

[0045] Also provided are methods of treating or preventing cancer, comprising administering to a subject a therapeutically or prophylactically effective amount of an antigen-binding molecule, a CAR, a nucleic acid or nucleic acids, an expression vector or vectors, a cell, or a composition according to the invention.

[0046] In some embodiments according to various aspects of the invention, the method further comprises administering an inhibitor of signaling mediated by an EGFR family member, optionally wherein the inhibitor of signaling mediated by an EGFR family member is an inhibitor of signaling mediated by HER2 and / or EGFR.

[0047] In some embodiments, the cancer is selected from cancers comprising cells that express an EGFR family member, cancers comprising cells that express HER3, solid tumors, breast cancer, breast cancer, ductal carcinoma, gastric cancer, gastric adenocarcinoma, colorectal cancer, colorectal adenocarcinoma, head and neck cancer, squamous cell carcinoma of the head and neck (SCCHN), lung cancer, lung adenocarcinoma, squamous cell lung carcinoma, ovarian cancer, ovarian carcinoma, serous ovarian adenocarcinoma, renal cancer, renal cell carcinoma, clear cell renal carcinoma, renal cell adenocarcinoma, papillary renal cell carcinoma, pancreatic cancer, pancreatic adenocarcinoma, pancreatic ductal adenocarcinoma, cervical cancer, squamous cell carcinoma of the cervix, skin cancer, melanoma, esophageal cancer, esophageal adenocarcinoma, liver cancer, hepatocellular carcinoma, cholangiocarcinoma, uterine cancer, endometrial carcinoma, thyroid cancer, thyroid carcinoma, pheochromocytoma, paraganglioma, bladder cancer, bladder urothelial carcinoma, prostate cancer, prostate adenocarcinoma, sarcoma, and thymoma.

[0048] Also provided is a method of inhibiting HER3-mediated signaling, comprising contacting a HER3-expressing cell with an antigen-binding molecule according to the invention.

[0049] Also provided is a method for reducing the number or activity of HER3-expressing cells, the method comprising contacting HER3-expressing cells with an antigen-binding molecule according to the invention.

[0050] Also provided is an in vitro complex, optionally an isolated in vitro complex, comprising an antigen-binding molecule according to the invention bound to HER3.

[0051] Also provided is a method comprising the steps of contacting a sample containing or suspected of containing HER3 with an antigen-binding molecule according to the present invention, and detecting the formation of a complex of the antigen-binding molecule with HER3.

[0052] Also provided is a method of selecting or stratifying a subject for treatment with a HER3 targeting agent, the method comprising the steps of contacting a sample from the subject in vitro with an antigen-binding molecule according to the invention, and detecting the formation of a complex of the antigen-binding molecule with HER3.

[0053] There is also provided the use of an antigen-binding molecule according to the invention as a diagnostic or prognostic agent in vitro or in vivo.

[0054] and optionally, the cancer is selected from the group consisting of cancers comprising cells that express an EGFR family member, cancers comprising cells that express HER3, solid tumors, breast cancer, breast cancer, ductal carcinoma, gastric cancer, gastric adenocarcinoma, colorectal cancer, colorectal adenocarcinoma, head and neck cancer, squamous cell carcinoma of the head and neck (SCCHN), lung cancer, lung adenocarcinoma, squamous cell lung carcinoma, ovarian cancer, ovarian cancer, serous ovarian adenocarcinoma, renal cancer, renal cell carcinoma, renal clear cell carcinoma, renal cell adenocarcinoma, papillary renal cell carcinoma, and pancreatic cancer. Also provided is the use of an antigen-binding molecule according to the present invention in a method for detecting, localizing, or imaging cancer selected from pancreatic adenocarcinoma, pancreatic ductal adenocarcinoma, cervical cancer, cervical squamous cell carcinoma, skin cancer, melanoma, esophageal cancer, esophageal adenocarcinoma, liver cancer, hepatocellular carcinoma, cholangiocarcinoma, uterine cancer, endometrial cancer, thyroid cancer, thyroid carcinoma, pheochromocytoma, paraganglioma, bladder cancer, bladder urothelial carcinoma, prostate cancer, prostate adenocarcinoma, sarcoma, and thymoma. DETAILED DESCRIPTION OF THE INVENTION

[0055] The present invention relates to novel HER3 binding molecules that have improved properties compared to known anti-HER3 antibodies.

[0056] The present inventors have contemplated the targeted generation of antigen-binding molecules that bind to specific regions of interest within the extracellular domain of HER3. The HER3-binding molecules of the present invention possess a combination of desirable biophysical and / or functional properties compared to antigen-binding molecules disclosed in the prior art.

[0057] In an embodiment of the invention, the antigen-binding molecule is capable of binding to subdomain II (SEQ ID NO: 16) of the extracellular region of HER3 and inhibits the association of the HER3 molecule to which it binds with an interaction partner.

[0058] In particular, the HER3-binding antigen-binding molecules described herein are demonstrated to bind to an epitope on HER3, resulting in potent inhibition of HER3 association with interacting partners, strong inhibition of downstream signaling, and exceptional anti-cancer activity against a wide range of cancers. HER3 HER3 (also known as, for example, ERBB3, LCCS2, MDA-BF-1) is a protein identified by UniProt: P21860. Alternative splicing of the mRNA encoded by the human ERBB3 gene results in five different isoforms: isoform 1 (UniProt: P21860-1, v1; SEQ ID NO: 1); isoform 2 (UniProt: P21860-2; SEQ ID NO: 2), which contains a sequence that differs from SEQ ID NO: 1 at position 141 and lacks the amino acid sequence corresponding to positions 183 to 1342 of SEQ ID NO: 1; isoform 3 (UniProt: P21860-3; SEQ ID NO: 3), which contains a substitution, C331F, compared to SEQ ID NO: 1 and lacks the amino acid sequence corresponding to positions 332 to 1342 of SEQ ID NO: 1; isoform 4 (UniProt: P21860-4; SEQ ID NO: 4), which lacks the amino acid sequence corresponding to positions 1 to 59 of SEQ ID NO: 1; and isoform 5 (UniProt: P21860-5; SEQ ID NO: 5), which lacks the amino acid sequence corresponding to positions 1 to 643 of SEQ ID NO: 1.

[0059] The N-terminal 19 amino acids of SEQ ID NOs: 1 to 3 constitute a signal peptide, and therefore the mature forms of HER3 isoforms 1, 2, and 3 (i.e., the forms after processing to remove the signal peptide) have the amino acid sequences shown in SEQ ID NOs: 6, 7, and 8, respectively.

[0060] The structure and function of HER3 are described in, for example, Cho and Leahy, Science (2002), 297(5585):1330-1333; Singer et al., Journal of Biological Chemistry (2001), 276, 44266-44274; Roskoski et al., Pharmacol. Res. (2014), 79:34-74; Bazley and Gullick, Endocrine-Related Cancer (2005), S17-S27; and Mujoo et al., Oncotarget (2014), 5(21):10222-10236. HER3 is a single-pass transmembrane ErbB receptor tyrosine kinase with an N-terminal extracellular region (SEQ ID NO: 9) containing two leucine-rich subdomains (domains I and III, shown in SEQ ID NOs: 15 and 17, respectively) and two cysteine-rich subdomains (domains II and IV, shown in SEQ ID NOs: 16 and 18, respectively). Domain II contains a β-hairpin dimerization loop (SEQ ID NO: 19) that is involved in intermolecular interactions with other HER receptor molecules. The extracellular region is connected to the cytoplasmic region (SEQ ID NO: 11) via a transmembrane region (SEQ ID NO: 10). The cytoplasmic region contains a membrane-proximal segment (SEQ ID NO: 12), a protein kinase domain (SEQ ID NO: 13), and a C-terminal segment (SEQ ID NO: 14).

[0061] Signaling through HER3 involves receptor homodimerization (i.e., with other HER3 receptors) or heterodimerization (with other HER receptors, e.g., HER2) and consequent autophosphorylation of the protein kinase domain on tyrosine in the cytoplasmic region. The phosphorylated tyrosine residue recruits adaptor / effector proteins containing src homology domain 2 (SH2) or phosphotyrosine-binding (PTB) domains, such as Grb2 and phospholipase Cγ (PLCγ).

[0062] Signal transduction via HER3 can be activated either ligand-dependently or ligand-independently.In the absence of ligand, HER3 receptor molecules are usually expressed as monomers on the cell surface, with a conformation that prevents receptor dimerization, in which the dimerization loop of subdomain II contacts the pocket on subdomain IV intracellularly.The binding of HER3 ligands, such as neuregulins (NRGs), for example, NRG1 (also known as heregulin, HRG) or NRG2, to the subdomains I and III of the extracellular region causes a conformational change, resulting in the exposure of the dimerization loop of subdomain II, facilitating receptor dimerization and signal transduction. Some cancer-associated mutations in HER3 disrupt the interaction between subdomains II and IV required for the formation of an inactive "closed" conformation, resulting in constitutive presentation of the dimerization loop and activation of HER3-mediated signaling in the absence of ligand binding (see, e.g., Jaiswal et al., Cancer Cell (2013), 23(5):603-617).

[0063] As used herein, "HER3" refers to HER3 from any species, and includes isoforms, fragments, variants (including mutants), or homologs of HER3 from any species.

[0064] As used herein, a "fragment," "variant," or "homologue" of a protein may optionally be characterized as having at least 60%, preferably at least one of 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of a reference protein (e.g., a reference isoform). In some embodiments, Fragments, variants, isoforms, and homologs of a reference protein can be characterized by their ability to perform a function performed by the reference protein.

[0065] A "fragment" generally refers to a portion of a reference protein. A "variant" generally refers to a protein having an amino acid sequence that contains one or more amino acid substitutions, insertions, deletions, or other modifications compared to the amino acid sequence of the reference protein, but that retains a significant degree of sequence identity (e.g., at least 60%) to the amino acid sequence of the reference protein. An "isoform" generally refers to a variant of a reference protein that is expressed by the same species as the reference protein (e.g., HER3 isoforms 1-5 are all isoforms of each other). A "homologue" generally refers to a variant of a reference protein that is produced by a different species compared to the species of the reference protein. For example, human HER3 isoform 1 (P21860-1, v1; SEQ ID NO: 1) and rhesus monkey HER3 (UniProt: F7HEH3-1, v2; SEQ ID NO: 20) are homologs of each other. Homologues include orthologs.

[0066] A "fragment" of a reference protein can be of any length (by number of amino acids), but can optionally be at least 20% of the length of the reference protein (i.e., the protein from which the fragment is derived), and can have a maximum length of one of 50%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99% of the length of the reference protein.

[0067] A fragment of HER3 can have a minimum length of one of 10, 20, 30, 40, 50, 100, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1100, 1200 amino acids and can have a maximum length of one of 20, 30, 40, 50, 100, 150, 200, 250, 300, 350, 400, 450, 500, 600, 700, 800, 900, 1000, 1100, 1200, or 1300 amino acids.

[0068] In some embodiments, the HER3 is mammalian-derived HER3 (e.g., primate (rhesus monkey, cynomolgus monkey, non-human primate, or human) and / or rodent (e.g., rat or mouse) HER3). HER3 isoforms, fragments, variants, or homologs may optionally be characterized as having at least 70%, preferably 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of an immature or mature HER3 isoform from a given species, e.g., human.

[0069] The isoform, fragment, variant, or homologue may optionally be a functional isoform, fragment, variant, or homologue that has the functional property / activity of a reference HER3 (e.g., human HER3 isoform 1), as determined, for example, by analysis via an appropriate assay for the functional property / activity. For example, an isoform, fragment, variant, or homologue of HER3 may exhibit association with one or more of HER2, NRG1 (types I, II, III, IV, V, or VI), or NRG2 (α or β).

[0070] In some embodiments, HER3 comprises or consists of an amino acid sequence having at least 70%, preferably 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequences of SEQ ID NOs: 1-8.

[0071] In some embodiments, the fragment of HER3 is SEQ ID NO: 9-19, e.g., SEQ ID NO: 9, 1 The amino acid sequence comprises or consists of an amino acid sequence having at least 70%, preferably 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to one of the amino acid sequences of one of the following: A region of particular interest on the target molecule The antigen-binding molecules of the present invention were specifically designed to target specific regions of HER3. In a two-step approach, the HER3 region to be targeted was selected based on predicted antigenicity, function, and safety analyses. Then, peptides corresponding to the target region were used as immunogens to elicit specific monoclonal antibodies, thereby preparing antibodies specific to the target region of HER3. Subsequent screening identified antibodies capable of binding to HER3 in the naive state. This approach allows for precise control over the antibody epitope.

[0072] Antigen-binding molecules of the present invention can be defined by reference to the region of HER3 to which they bind. Antigen-binding molecules of the present invention can bind to a region of HER3 of particular interest. In some embodiments, antigen-binding molecules can bind to a linear epitope of HER3 consisting of a contiguous sequence of amino acids (i.e., a primary sequence of amino acids). In some embodiments, antigen-binding molecules can bind to a conformational epitope of HER3 consisting of a discontinuous sequence of amino acids within the amino acid sequence.

[0073] In some embodiments, the antigen-binding molecules of the present invention bind to HER3. In some embodiments, the antigen-binding molecules bind to the extracellular region of HER3 (e.g., the region set forth in SEQ ID NO: 9). In some embodiments, the antigen-binding molecules bind to subdomain II of the extracellular region of HER3 (e.g., the region set forth in SEQ ID NO: 16).

[0074] In some embodiments, the antigen-binding molecule binds to a region of HER3 set forth in SEQ ID NO: 229. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 229. In some embodiments, the antigen-binding molecule binds to a region of HER3 set forth in SEQ ID NOs: 230 and 231. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 230 and 231. In some embodiments, the antigen-binding molecule binds to a region of HER3 set forth in SEQ ID NO: 230. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 230. In some embodiments, the antigen-binding molecule binds to a region of HER3 set forth in SEQ ID NO: 231. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 231.

[0075] In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 23. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 23. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 21. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 21. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 19. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 19. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 22. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 22.

[0076] In some embodiments, the antigen-binding molecule comprises a sequence corresponding to positions 260-279 of SEQ ID NO: 1. Does not bind to a region of HER3. In some embodiments, the antigen-binding molecule does not contact amino acid residues in the region of HER3 corresponding to positions 260 to 279 of SEQ ID NO: 1. In some embodiments, the antigen-binding molecule does not bind to a region of HER3 shown in SEQ ID NO: 23. In some embodiments, the antigen-binding molecule does not contact amino acid residues in the region of HER3 shown in SEQ ID NO: 23.

[0077] The region of a peptide / polypeptide to which an antibody binds can be determined by those skilled in the art using a variety of methods known in the art, including X-ray cocrystallography of antibody-antigen complexes, peptide scanning, mutagenesis mapping, mass spectrometric hydrogen-deuterium exchange analysis, phage display, competitive ELISA, and proteolysis-based "protection" methods. Such methods are described, for example, in Gershoni et al., BioDrugs, 2007, 21(3):145-156, which is incorporated herein by reference in its entirety.

[0078] In some embodiments, the antigen-binding molecule is capable of binding to the same or overlapping region of HER3 as that of an antibody comprising the VH and VL sequences of one of the antibody clones described herein: 10D1, 10D1_c75, 10D1_c76, 10D1_c77, 10D1_c78v1, 10D1_c78v2, 10D1_11B, 10D1_c85v1, 10D1_c85v2, 10D1_c85o1, 10D1_c85o2, 10D1_c87, 10D1_c89, 10D1_c90, 10D1_c91, 10D1_c92, 10D1_c93, 10A6, 4-35-B2, or 4-35-B4. In some embodiments, the antigen-binding molecule is capable of binding to the same region of HER3 as, or an overlapping region of HER3, bound by, an antibody comprising the VH and VL sequences of one of the antibody clones 10D1_c89, 10D1_c90, or 10D1_c91. In some embodiments, the antigen-binding molecule is capable of binding to the same region of HER3 as, or an overlapping region of HER3, bound by, an antibody comprising the VH and VL sequences of the antibody clone 10D1_c89.

[0079] As used herein, "peptide" refers to a chain of two or more amino acid monomers linked by peptide bonds. Peptides are typically about 2 to 50 amino acids in length. A "polypeptide" is a polymeric chain of two or more peptides. Polypeptides are typically greater than about 50 amino acids in length.

[0080] In some embodiments, an antigen-binding molecule of the invention is capable of binding to a polypeptide comprising or consisting of the amino acid sequence of one of SEQ ID NOs: 1, 3, 4, 6, or 8.

[0081] In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 9. In some embodiments, the antigen-binding molecule is capable of binding to a polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 16.

[0082] In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 229. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NOs: 230 and 231. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 230. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 231. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 23. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 21. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 19. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 22.

[0083] In some embodiments, the antigen-binding molecule is not capable of binding to a peptide consisting of the amino acid sequence corresponding to positions 260 to 279 of SEQ ID NO: 1. In some embodiments, the antigen-binding molecule is not capable of binding to a peptide consisting of the amino acid sequence of SEQ ID NO: 23.

[0084] The ability of an antigen-binding molecule to bind to a given peptide / polypeptide can be analyzed by methods well known to those skilled in the art, including analysis by ELISA, immunoblot (e.g., Western blot), immunoprecipitation, surface plasmon resonance (SPR; see, e.g., Hearty et al., Methods Mol Biol (2012), 907:411-442), or biolayer interferometry (see, e.g., Lad et al. (2015), J Biomol Screen, 20(4):498-507).

[0085] In embodiments in which the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising a reference amino acid sequence, the peptide / polypeptide may comprise one or more additional amino acids at one or both termini of the reference amino acid sequence. In some embodiments, the peptide / polypeptide comprises, for example, 1 to 5, 1 to 10, 1 to 20, 1 to 30, 1 to 40, 1 to 50, 5 to 10, 5 to 20, 5 to 30, 5 to 40, 5 to 50, 10 to 20, 10 to 30, 10 to 40, 10 to 50, 20 to 30, 20 to 40, or 20 to 50 additional amino acids at one or both termini of the reference amino acid sequence.

[0086] In some embodiments, in the context of the amino acid sequence of HER3, the additional amino acid(s) provided at one or both ends (i.e., the N-terminus and C-terminus) of the reference sequence correspond to positions at the ends of the reference sequence. By way of example, if an antigen-binding molecule is capable of binding to a peptide comprising the sequence of SEQ ID NO:23 and two additional amino acids at the C-terminus of SEQ ID NO:23, the two additional amino acids may be threonine and lysine, corresponding to positions 278 and 279 of SEQ ID NO:1.

[0087] In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide to which an antibody comprising the VH and VL sequences of one of the antibody clones described herein: 10D1, 10D1_c75, 10D1_c76, 10D1_c77, 10D1_c78v1, 10D1_c78v2, 10D1_11B, 10D1_c85v1, 10D1_c85v2, 10D1_c85o1, 10D1_c85o2, 10D1_c87, 10D1_c89, 10D1_c90, 10D1_c91, 10D1_c92, 10D1_c93, 10A6, 4-35-B2, or 4-35-B4. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide bound by an antibody comprising the VH and VL sequences of one of the antibody clones 10D1_c89, 10D1_c90, or 10D1_c91. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide bound by an antibody comprising the VH and VL sequences of the antibody clone 10D1_c89. antigen binding molecule The present invention provides antigen-binding molecules capable of binding to HER3.

[0088] "Antigen-binding molecule" refers to a molecule capable of binding to a target antigen, and includes monoclonal antibodies, polyclonal antibodies, monospecific antibodies and multispecific antibodies (e.g., bispecific antibodies), as well as antibody fragments (e.g., Fv, scFv, Fab, scFab, F(ab')2, Fab2, diabodies, triabodies, scFv-Fc, minibodies, single domain antibodies (e.g., VhH), etc.), so long as they exhibit binding to the intended target molecule(s).

[0089] The antigen-binding molecules of the present invention comprise a moiety capable of binding to a target antigen(s). In some embodiments, the moiety capable of binding to a target antigen comprises an antibody heavy chain variable region (VH) and an antibody light chain variable region (VL) of an antibody capable of specifically binding to the target antigen. In some embodiments, the moiety capable of binding to the target antigen comprises or consists of an aptamer capable of binding to the target antigen, such as a nucleic acid aptamer (reviewed, e.g., in Zhou and Rossi, Nat Rev Drug Discov., 2017, 16(3):181-202). In some embodiments, the moiety capable of binding to a target antigen is an antigen-binding peptide / polypeptide, such as a peptide aptamer, thioredoxin, monobody, anticalin, Kunitz domain, avimer, knottin, fynomer, atrimer, DARPin, affibody, nanobody (i.e., single domain antibody (sdAb)), affilin, armadillo repeat protein (ArmRP), OBody, or fibronectin (e.g., Reverdatto et al., Curr Top Med Chem., 2015, 15(12):1082-1101 (see also, e.g., Boersma et al., J Biol Chem (2011), 286:41273-85; and Emanuel et al., Mab (2011), 3:38-48).

[0090] The antigen-binding molecules of the present invention generally comprise an antigen-binding domain, comprising an antibody VH and VL, capable of specifically binding to a target antigen. Herein, the antigen-binding domain formed by the VH and VL is also referred to as an Fv region.

[0091] An antigen-binding molecule may be or comprise an antigen-binding polypeptide or antigen-binding polypeptide complex. An antigen-binding molecule may comprise more than one polypeptide that together form an antigen-binding domain. The polypeptides may be covalently or non-covalently associated. In some embodiments, the polypeptide forms part of a larger polypeptide that comprises the polypeptide (e.g., in the case of an scFv comprising a VH and a VL, or in the case of an scFab comprising a VH-CH1 and a VL-CL).

[0092] An antigen-binding molecule may refer to a non-covalent or covalent complex of an IgG-like antigen-binding molecule that includes more than one polypeptide (e.g., two, three, four, six, or eight polypeptides), e.g., two heavy chain polypeptides and two light chain polypeptides.

[0093] The antigen-binding molecules of the present invention can be designed and prepared using the sequence of a monoclonal antibody (mAb) capable of binding to HER3. Antigen-binding regions of antibodies, such as single-chain variable fragments (scFv), Fab, and F(ab')2 fragments, can also be used / derived. An "antigen-binding region" is any fragment of an antibody capable of binding to a target for which a given antibody is specific.

[0094] Antibodies generally contain six complementarity-determining regions, or CDRs: three in the heavy chain variable (VH) region: HC-CDR1, HC-CDR2, and HC-CDR3, and three in the light chain variable (VL) region: LC-CDR1, LC-CDR2, and LC-CDR3. Together, the six CDRs define the paratope of the antibody, the portion of the antibody that binds to the target antigen.

[0095] The VH and VL regions comprise, on either side of each CDR, framework regions (FRs) that provide a scaffold for the CDRs. From N- to C-terminus, the VH region comprises the following structure: N-terminus-[HC-FR1]-[HC-CDR1]-[HC-FR2]-[HC-CDR2]-[HC-FR3]-[HC-CDR3]-[HC-FR4]-C-terminus, and the VL region comprises the following structure: N-terminus-[LC-FR1]-[LC-CDR1]-[LC-FR2]-[LC-CDR2]-[LC-FR3]-[LC-CDR3]-[LC-FR4]-C-terminus.

[0096] There are several different conventions for defining the CDRs and FRs of antibodies, such as the convention described in Kabat et al., "Sequences of Proteins of Immunological Interest," 5th ed., Public Health Service, National Institutes of Health, Bethesda, MD (1991); Chothia et al., J. Mol. Biol., 196:901-917 (1987), and VBASE2, described in Retter et al., Nucl. Acids Res., (2005), 33(Suppl. 1):D671-D674. The CDRs and FRs of the VH and VL regions of the antibody clones described herein were defined according to the international IMGT (ImMunoGeneTics) information system (LeFranc et al., Nucleic Acids Res. (2015), 43(Database Issue):D413-22), using the IMGT V-domain numbering convention described in Lefranc et al., Dev. Comp. Immunol. (2003), 27:55-77.

[0097] In some embodiments, the antigen-binding molecule comprises the CDRs of an antigen-binding molecule capable of binding to HER3. In some embodiments, the antigen-binding molecule comprises the FRs of an antigen-binding molecule capable of binding to HER3. In some embodiments, the antigen-binding molecule comprises the CDRs and FRs of an antigen-binding molecule capable of binding to HER3. That is, in some embodiments, the antigen-binding molecule comprises the VH region and VL region of an antigen-binding molecule capable of binding to HER3.

[0098] In some embodiments, the antigen-binding molecule is selected from the group consisting of HER3-binding antibody clones described herein (i.e., anti-HER3 antibody clones 10D1_c75, 10D1_c76, 10D1_c77, 10D1_c78v1, 10D1_c78v2, 10D1_11B, 10D1_c85v1, 10D1_c85v2, 10D1_c85o1, 10D1_c85o2, 10D1_c85v3, 10D1_c85o1, 10D1_c85o2, 10D1_c85v4, 10D1_c85v5, 10D1_c85v6, 10D1_c85v7, 10D1_c85v8, 10D1_c85v9, 10D1_c85v1, 10D1_c85v2, 10D1_c85v1, 10D1_c85v2, 10D1_c85v2, 10D1_c85v3, 10D1_c85v4, 10D1_c85v5, 10D1_c85v6, 10D1_c85v7, 10D1_c85v8, 10D1_c85v9, 10D1_c85v1, 10D1_c85v2 ... and / or 4-35-B4; e.g., 10D1_c89, 10D1_c90, or 10D1_c91; e.g., 10D1_c89).

[0099] In some embodiments, the antigen-binding molecule comprises a VH region according to one of (1) to (10) below.

[0100] (1) The following CDRs (derived from 10D1): HC-CDR1 having the amino acid sequence of SEQ ID NO: 43 HC-CDR2 having the amino acid sequence of SEQ ID NO: 46 HC-CDR3 having the amino acid sequence of SEQ ID NO: 51; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0101] (2) The following CDRs (10D1, 10D1_c75, 10D1_c76, 10D1_c77, 10D1_c78v1, 10D1_c78v2, 10D1_11B, 10D1_c87, 10D1_c92, 10D1_c93): HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0102] (3) The following CDRs (10D1_c85v1, 10D1_c85v2): HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0103] (4) The following CDR (from 10D1_c85o1): HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 49; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0104] (5) The following CDR (from 10D1_c85o2): HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 50; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0105] (6) The following CDRs (10D1_c89, 10D1_c90): HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0106] (7) The following CDR (from 10D1_c91): HC-CDR1 having the amino acid sequence of SEQ ID NO: 42 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0107] (8) The following CDR (of 10A6): HC-CDR1 having the amino acid sequence of SEQ ID NO: 158 HC-CDR2 having the amino acid sequence of SEQ ID NO: 159 HC-CDR3 having the amino acid sequence of SEQ ID NO: 160; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0108] (9) The following CDR (4-35-B2): HC-CDR1 having the amino acid sequence of SEQ ID NO: 128 HC-CDR2 having the amino acid sequence of SEQ ID NO: 129 HC-CDR3 having the amino acid sequence of SEQ ID NO: 130; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0109] (10) The following CDR (4-35-B4): HC-CDR1 having the amino acid sequence of SEQ ID NO: 144 HC-CDR2 having the amino acid sequence of SEQ ID NO: 145 HC-CDR3 having the amino acid sequence of SEQ ID NO: 146; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-CDR1, HC-CDR2, or HC-CDR3 have been replaced with another amino acid.

[0110] In some embodiments, the antigen-binding molecule comprises a VH region according to one of (11) to (24) below.

[0111] (11) The following FR (of 10D1): HC-FR1 having the amino acid sequence of SEQ ID NO: 55 HC-FR2 having the amino acid sequence of SEQ ID NO: 58 HC-FR3 having the amino acid sequence of SEQ ID NO: 69 HC-FR4 having the amino acid sequence of SEQ ID NO: 73; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0112] (12) The following FR (10D1_c75, 10D1_c92): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 56 HC-FR3 having the amino acid sequence of SEQ ID NO: 61 HC-FR4 having the amino acid sequence of SEQ ID NO: 70; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0113] (13) The following FRs (10D1_c76, 10D1_c77, 10D1_c78v1): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 56 HC-FR3 having the amino acid sequence of SEQ ID NO: 62 HC-FR4 having the amino acid sequence of SEQ ID NO: 70; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0114] (14)(10D1_c78v2) The following FR: HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 57 HC-FR3 having the amino acid sequence of SEQ ID NO: 62 HC-FR4 having the amino acid sequence of SEQ ID NO: 70; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0115] (15) The following FR (10D1_11B): HC-FR1 having the amino acid sequence of SEQ ID NO: 224 HC-FR2 having the amino acid sequence of SEQ ID NO: 60 HC-FR3 having the amino acid sequence of SEQ ID NO: 63 HC-FR4 having the amino acid sequence of SEQ ID NO: 70; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0116] (16)(10D1_c85v1) The following FR: HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 56 HC-FR3 having the amino acid sequence of SEQ ID NO: 64 HC-FR4 having the amino acid sequence of SEQ ID NO: 70; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0117] (17) The following FRs (10D1_c85v2, 10D1_c85o1, 10D1_c85o2): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 57 HC-FR3 having the amino acid sequence of SEQ ID NO: 64 HC-FR4 having the amino acid sequence of SEQ ID NO: 70; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0118] (18) The following FR (10D1_c87, 10D1_c93): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 56 HC-FR3 having the amino acid sequence of SEQ ID NO: 65 HC-FR4 having the amino acid sequence of SEQ ID NO: 70; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0119] (19)(10D1_c89) The following FR: HC-FR1 having the amino acid sequence of SEQ ID NO: 53 HC-FR2 having the amino acid sequence of SEQ ID NO: 59 HC-FR3 having the amino acid sequence of SEQ ID NO: 66 HC-FR4 having the amino acid sequence of SEQ ID NO: 71; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0120] (20)(10D1_c90) The following FR: HC-FR1 having the amino acid sequence of SEQ ID NO: 54 HC-FR2 having the amino acid sequence of SEQ ID NO: 59 HC-FR3 having the amino acid sequence of SEQ ID NO: 67 HC-FR4 having the amino acid sequence of SEQ ID NO: 71; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0121] (21)(10D1_c91) The following FR: HC-FR1 having the amino acid sequence of SEQ ID NO: 53 HC-FR2 having the amino acid sequence of SEQ ID NO: 59 HC-FR3 having the amino acid sequence of SEQ ID NO: 68 HC-FR4 having the amino acid sequence of SEQ ID NO: 72; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0122] (22) The following FR (of 10A6): HC-FR1 having the amino acid sequence of SEQ ID NO: 161 HC-FR2 having the amino acid sequence of SEQ ID NO: 162 HC-FR3 having the amino acid sequence of SEQ ID NO: 163 HC-FR4 having the amino acid sequence of SEQ ID NO: 73; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0123] (23) The following FR (4-35-B2): HC-FR1 having the amino acid sequence of SEQ ID NO: 131 HC-FR2 having the amino acid sequence of SEQ ID NO: 132 HC-FR3 having the amino acid sequence of SEQ ID NO: 133 HC-FR4 having the amino acid sequence of SEQ ID NO: 134; or one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 have been substituted with another amino acid. , VH regions incorporating these mutations.

[0124] (24) The following FR (4-35-B4): HC-FR1 having the amino acid sequence of SEQ ID NO: 147 HC-FR2 having the amino acid sequence of SEQ ID NO: 148 HC-FR3 having the amino acid sequence of SEQ ID NO: 149 HC-FR4 having the amino acid sequence of SEQ ID NO: 73; or a VH region incorporating these variants in which one, two, or three amino acids in one or more of HC-FR1, HC-FR2, HC-FR3, or HC-FR4 are replaced with another amino acid.

[0125] In some embodiments, the antigen-binding molecule comprises a VH region comprising a CDR according to one of (1) to (10) above and a FR according to one of (11) to (24) above.

[0126] In some embodiments, the antigen-binding molecule comprises a VH region according to one of (25) to (41) below.

[0127] (25) A VH region comprising a CDR according to (1) and a FR according to (11), (12), (13), (14), (15), (16), (17), (18), (19), (20), or (21).

[0128] (26) A VH region comprising a CDR according to (2) and a FR according to (11).

[0129] (27) A VH region comprising a CDR according to (2) and a FR according to (12).

[0130] (28) A VH region comprising a CDR according to (2) and a FR according to (13).

[0131] (29) A VH region comprising a CDR according to (2) and a FR according to (14).

[0132] (30) A VH region comprising a CDR according to (2) and a FR according to (15).

[0133] (31) A VH region comprising a CDR according to (2) and a FR according to (18).

[0134] (32) A VH region comprising a CDR according to (3) and a FR according to (16).

[0135] (33) A VH region comprising a CDR according to (3) and a FR according to (17).

[0136] (34) A VH region comprising a CDR according to (4) and a FR according to (17).

[0137] (35) A VH region comprising a CDR according to (5) and a FR according to (17).

[0138] (36) A VH region comprising a CDR according to (6) and a FR according to (19).

[0139] (37) A VH region comprising a CDR according to (6) and a FR according to (20).

[0140] (38) A VH region comprising a CDR according to (7) and a FR according to (21).

[0141] (39) A VH region comprising a CDR according to (8) and a FR according to (22).

[0142] (40) A VH region comprising a CDR according to (9) and a FR according to (23).

[0143] (41) A VH region comprising a CDR according to (10) and a FR according to (24).

[0144] In some embodiments, the antigen-binding molecule comprises a VH region according to one of (42) to (61) below.

[0145] (42) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 24.

[0146] (43) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 25.

[0147] (44) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 26.

[0148] (45) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 27.

[0149] (46) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 28.

[0150] (47) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 29.

[0151] (48) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 30.

[0152] (49) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 31.

[0153] (50) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 32.

[0154] (51) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 33.

[0155] (52) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 34.

[0156] (53) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 35.

[0157] (54) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 36.

[0158] (55) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 37.

[0159] (56) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 38.

[0160] (57) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 39.

[0161] (58) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 40.

[0162] (59) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 127.

[0163] (60) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 143.

[0164] (61) A VH region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 157.

[0165] In some embodiments, the antigen-binding molecule comprises a VL region according to one of (62) to (71) below.

[0166] (62) The following CDRs (derived from 10D1): LC-CDR1 having the amino acid sequence of SEQ ID NO: 91 LC-CDR2 having the amino acid sequence of SEQ ID NO: 94 LC-CDR3 having the amino acid sequence of SEQ ID NO: 99; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0167] (63) The following CDRs (10D1, 10D1_c75, 10D1_c78v1, 10D1_c78v2, 10D1_11B, 10D1_c87, 10D1_c89, 10D1_c91, 10D1_c93): LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0168] (64) The following CDR (of 10D1_c76): LC-CDR1 having the amino acid sequence of SEQ ID NO: 89 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0169] (65) The following CDR (of 10D1_c77): LC-CDR1 having the amino acid sequence of SEQ ID NO: 90 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 96; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0170] (66) The following CDRs (10D1_c85v1, 10D1_c85v2, 10D1_c85o1, 10D1_c85o2): LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95; or in which one, two or three amino acids in one or more of LC-CDR1, LC-CDR2 or LC-CDR3 have been replaced with another amino acid. VL region incorporating the mutation.

[0171] (67) The following CDR (of 10D1_c90): LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 97; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0172] (68) The following CDR (of 10D1_c92): LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 98; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0173] (69) The following CDR (of 10A6): LC-CDR1 having the amino acid sequence of SEQ ID NO: 165 LC-CDR2 having the amino acid sequence of SEQ ID NO: 166 LC-CDR3 having the amino acid sequence of SEQ ID NO: 167; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0174] (70) The following CDR (of 4-35-B2): LC-CDR1 having the amino acid sequence of SEQ ID NO: 136 LC-CDR2 having the amino acid sequence of SEQ ID NO: 137 LC-CDR3 having the amino acid sequence of SEQ ID NO: 138; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0175] (71) The following CDR (of 4-35-B4): LC-CDR1 having the amino acid sequence of SEQ ID NO: 151 LC-CDR2 having the amino acid sequence of SEQ ID NO: 152 LC-CDR3 having the amino acid sequence of SEQ ID NO: 153; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-CDR1, LC-CDR2, or LC-CDR3 are replaced with another amino acid.

[0176] In some embodiments, the antigen-binding molecule comprises a VL region according to one of (72) to (86) below.

[0177] (72) (10D1) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 106 LC-FR2 having the amino acid sequence of SEQ ID NO: 113 LC-FR3 having the amino acid sequence of SEQ ID NO: 123 LC-FR4 having the amino acid sequence of SEQ ID NO: 126; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0178] (73)(10D1_c75) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 100 LC-FR2 having the amino acid sequence of SEQ ID NO: 107 LC-FR3 having the amino acid sequence of SEQ ID NO: 114 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0179] (74)(10D1_c76) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 101 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 115 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0180] (75)(10D1_c77) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 102 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 116 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0181] (76)(10D1_c78v1, 10D1_c78v2, 10D1_11B) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 103 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 117 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0182] (77) The following FRs (10D1_c85v1, 10D1_c85v2, 10D1_c85o1, 10D1_c85o2): LC-FR1 having the amino acid sequence of SEQ ID NO: 103 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 118 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0183] (78)(10D1_c87) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 103 LC-FR2 having the amino acid sequence of SEQ ID NO: 109 LC-FR3 having the amino acid sequence of SEQ ID NO: 119 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0184] (79)(10D1_c89) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 104 LC-FR2 having the amino acid sequence of SEQ ID NO: 110 LC-FR3 having the amino acid sequence of SEQ ID NO: 120 LC-FR4 having the amino acid sequence of SEQ ID NO: 125; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0185] (80)(10D1_c90) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 105 LC-FR2 having the amino acid sequence of SEQ ID NO: 110 LC-FR3 having the amino acid sequence of SEQ ID NO: 121 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0186] (81)(10D1_c91) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 104 LC-FR2 having the amino acid sequence of SEQ ID NO: 111 LC-FR3 having the amino acid sequence of SEQ ID NO: 122 LC-FR4 having the amino acid sequence of SEQ ID NO: 125; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0187] (82)(10D1_c92) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 100 LC-FR2 having the amino acid sequence of SEQ ID NO: 112 LC-FR3 having the amino acid sequence of SEQ ID NO: 114 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0188] (83)(10D1_c93) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 103 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 119 LC-FR4 having the amino acid sequence of SEQ ID NO: 124; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0189] (84)(10A6) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 168 LC-FR2 having the amino acid sequence of SEQ ID NO: 169 LC-FR3 having the amino acid sequence of SEQ ID NO: 170 LC-FR4 having the amino acid sequence of SEQ ID NO: 142; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0190] (85)(4-35-B2) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 139 LC-FR2 having the amino acid sequence of SEQ ID NO: 140 LC-FR3 having the amino acid sequence of SEQ ID NO: 141 LC-FR4 having the amino acid sequence of SEQ ID NO: 142; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0191] (86)(4-35-B4) The following FR: LC-FR1 having the amino acid sequence of SEQ ID NO: 154 LC-FR2 having the amino acid sequence of SEQ ID NO: 155 LC-FR3 having the amino acid sequence of SEQ ID NO: 156 LC-FR4 having the amino acid sequence of SEQ ID NO: 142; or a VL region incorporating these variants in which one, two, or three amino acids in one or more of LC-FR1, LC-FR2, LC-FR3, or LC-FR4 are replaced with another amino acid.

[0192] In some embodiments, the antigen-binding molecule comprises a VL region comprising a CDR according to one of (62) to (71) above and a FR according to one of (72) to (86) above.

[0193] In some embodiments, the antigen-binding molecule comprises a VL region according to one of (87) to (102) below.

[0194] (87) A VL region comprising a CDR according to (62) and a FR according to (72), (73), (74), (75), (76), (77), (78), (79), (80), (81), (82), or (83).

[0195] (88) A VL region comprising CDRs according to (63) and FRs according to (72).

[0196] (89) A VL region comprising CDRs according to (63) and FRs according to (73).

[0197] (90) A VL region comprising CDRs according to (63) and FRs according to (76).

[0198] (91) A VL region comprising CDRs according to (63) and FRs according to (78).

[0199] (92) A VL region comprising CDRs according to (63) and FRs according to (79).

[0200] (93) A VL region comprising CDRs according to (63) and FRs according to (81).

[0201] (94) A VL region comprising CDRs according to (63) and FRs according to (83).

[0202] (95) A VL region comprising CDRs according to (64) and FRs according to (74).

[0203] (96) A VL region comprising CDRs according to (65) and FRs according to (75).

[0204] (97) A VL region comprising CDRs according to (66) and FRs according to (77).

[0205] (98) A VL region comprising CDRs according to (67) and FRs according to (80).

[0206] (99) A VL region comprising CDRs according to (68) and FRs according to (82).

[0207] (100) A VL region comprising CDRs according to (69) and FRs according to (84).

[0208] (101) A VL region comprising CDRs according to (70) and FRs according to (85).

[0209] (102) A VL region comprising CDRs according to (71) and FRs according to (86).

[0210] In some embodiments, the antigen-binding molecule comprises a VL region according to one of (103) to (119) below.

[0211] (103) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 74.

[0212] (104) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 75.

[0213] (105) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 76.

[0214] (106) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 77.

[0215] (107) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 78.

[0216] (108) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 79.

[0217] (109) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 80.

[0218] (110) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 81.

[0219] (111) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 82.

[0220] (112) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 83.

[0221] (113) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 84.

[0222] (114) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 85.

[0223] (115) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 86.

[0224] (116) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 87.

[0225] (117) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 135.

[0226] (118) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 150.

[0227] (119) A VL region comprising an amino acid sequence having at least 70% sequence identity, more preferably at least 75%, 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of SEQ ID NO: 164.

[0228] In some embodiments, the antigen-binding molecule comprises a VH region according to any one of (1) to (61) above and a VL region according to any one of (62) to (119) above.

[0229] In embodiments according to the invention in which one or more amino acids are substituted with another amino acid, the substitutions may be conservative substitutions, for example, according to the following table: In some embodiments, amino acids in the same block in the middle column are substituted; In some embodiments, amino acids in the same stretch in the rightmost column are substituted.

[0230] [Table 1] In some embodiments, the substitution(s) may be functionally conservative, i.e., in some embodiments, the substitution may not affect (or may not substantially affect) one or more functional properties (e.g., target binding) of an antigen-binding molecule comprising the substitution compared to a comparable unsubstituted molecule.

[0231] The VH and VL regions of the antigen-binding region of an antibody together constitute an Fv region. In some embodiments, an antigen-binding molecule according to the present invention comprises or consists of an Fv region that binds to HER3. In some embodiments, the VH and VL regions of the Fv are provided as a single polypeptide, i.e., a single-chain Fv (scFv), joined by a linker region.

[0232] In some embodiments, the antigen-binding molecules of the present invention comprise one or more regions of an immunoglobulin heavy chain constant sequence, which is or is derived from an IgG (e.g., IgG1, IgG2, IgG3, IgG4), IgA (e.g., IgA1, IgA2), IgD, IgE, or IgM heavy chain constant sequence.

[0233] In some embodiments, the immunoglobulin heavy chain constant sequence is the human immunoglobulin G1 constant sequence (IGHG1; UniProt: P01857-1, v1; SEQ ID NO: 171). Positions 1 to 98 of SEQ ID NO: 171 form the CH1 region (SEQ ID NO: 172). Positions 99 to 110 of SEQ ID NO: 171 form the hinge region between the CH1 and CH2 regions (SEQ ID NO: 173). Positions 111 to 223 of SEQ ID NO: 171 form the CH2 region (SEQ ID NO: 174). Positions 224 to 330 of SEQ ID NO: 171 form the CH3 region (SEQ ID NO: 175).

[0234] An exemplary antigen-binding molecule can be prepared using pFUSE-CHIg-hG1, which contains the substitutions D356E, L358M (positions numbered according to EU numbering) in the CH3 region. The amino acid sequence of the CH3 region encoded by pFUSE-CHIg-hG1 is set forth in SEQ ID NO: 176. It will be understood that the CH3 region can be further substituted in accordance with the modifications to the Fc region of the antigen-binding molecule described herein.

[0235] In some embodiments, the CH1 region comprises or consists of the sequence of SEQ ID NO: 172, or a sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 172. In some embodiments, the hinge region between CH1 and CH2 comprises or consists of the sequence of SEQ ID NO: 173, or a sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 173. In some embodiments, the CH2 region comprises or consists of the sequence of SEQ ID NO: 174, or a sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 174. In some embodiments, the CH3 region comprises or consists of the sequence of SEQ ID NO: 175 or 176, or a sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 175 or 176.

[0236] In some embodiments, the antigen-binding molecules of the present invention comprise one or more regions of an immunoglobulin light chain constant sequence. In some embodiments, the immunoglobulin light chain constant sequence is a human immunoglobulin kappa constant sequence (IGKC; Cκ; UniProt: P01834-1, v2; SEQ ID NO: 177). In some embodiments, the immunoglobulin light chain constant sequence is a human immunoglobulin lambda constant sequence (IGLC; Cλ), such as IGLC1, IGLC2, IGLC3, IGLC6, or IGLC7. In some embodiments, the CL region comprises or consists of the sequence of SEQ ID NO: 177 or a sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 177.

[0237] The VL and light chain constant (CL) region, and the VH region and heavy chain constant 1 (CH1) region of the antigen-binding region of an antibody together constitute a Fab region. In some embodiments, an antigen-binding molecule comprises a Fab region comprising a VH, CH1, VL, and CL (e.g., Cκ or Cλ). In some embodiments, the Fab region comprises a polypeptide comprising a VH and CH1 (e.g., a VH-CH1 fusion polypeptide), and a polypeptide comprising a VL and CL (e.g., a VL-CL fusion polypeptide). In some embodiments, the Fab region comprises a polypeptide comprising a VH and CL (e.g., a VH-CL fusion polypeptide), and a polypeptide comprising a VL and CH (e.g., a VL-CH1 fusion polypeptide); i.e., in some embodiments, the Fab region is a CrossFab region. In some embodiments, the VH, CH1, VL, and CL regions of a Fab or CrossFab are joined by a linker region to form a single polypeptide, i.e., a single-chain Fab (scFab) or It is provided as a single-chain CrossFab (scCrossFab).

[0238] In some embodiments, the antigen-binding molecules of the invention comprise or consist of a Fab region that binds to HER3.

[0239] In some embodiments, the antigen-binding molecules described herein comprise or consist of a whole antibody that binds to HER3. As used herein, "whole antibody" refers to an antibody that has a structure substantially similar to that of an immunoglobulin (Ig). For information on different types of immunoglobulins and their structures, see, for example, Schroeder and Cavacini, J Allergy, 1999, 14, 111-113, which is incorporated herein by reference in its entirety. It is described in Clin Immunol. (2010), 125(202):S41-S52.

[0240] G-type immunoglobulins (i.e., IgG) are glycoproteins of approximately 150 kDa that contain two heavy chains and two light chains. From the N-terminus to the C-terminus, the heavy chain contains a VH followed by a heavy chain constant region containing three constant domains (CH1, CH2, and CH3); similarly, the light chain contains a VL followed by a CL. Depending on the heavy chain, immunoglobulins can be classified as IgG (e.g., IgG1, IgG2, IgG3, IgG4), IgA (e.g., IgA1, IgA2), IgD, IgE, or IgM. The light chain can be either a kappa (κ) chain or a lambda (λ) chain.

[0241] In some embodiments, the antigen-binding molecules described herein comprise or consist of an IgG (e.g., IgG1, IgG2, IgG3, IgG4), IgA (e.g., IgA1, IgA2), IgD, IgE, or IgM that binds to HER3.

[0242] In some embodiments, the antigen-binding molecules of the present invention are at least monovalent binding molecules for HER3. Valency refers to the number of binding sites within an antigen-binding molecule for a given antigenic determinant. Thus, in some embodiments, the antigen-binding molecule comprises at least one binding site for HER3.

[0243] In some embodiments, the antigen-binding molecule comprises more than one binding site for HER3, e.g., two, three, or four binding sites. The binding sites may be the same or different. In some embodiments, the antigen-binding molecule is, for example, bivalent, trivalent, or tetravalent for HER3.

[0244] Aspects of the present invention relate to multispecific antigen-binding molecules. "Multispecific" means that an antigen-binding molecule specifically binds to more than one target. In some embodiments, the antigen-binding molecule is a bispecific antigen-binding molecule. In some embodiments, the antigen-binding molecule comprises at least two different antigen-binding domains (i.e., at least two antigen-binding domains comprising, for example, non-identical VH and VL).

[0245] In some embodiments, the antigen-binding molecule is at least bispecific, as it binds to HER3 and another target (e.g., an antigen other than HER3). The term "bispecific" means that the antigen-binding molecule is capable of specifically binding to at least two distinct antigenic determinants.

[0246] It will be understood that antigen-binding molecules (e.g., multispecific antigen-binding molecules) according to the present invention may include antigen-binding molecules capable of binding to a target for which the antigen-binding molecule is specific. For example, antigen-binding molecules capable of binding to HER3 and antigens other than HER3 include (i) antigen-binding molecules capable of binding to HER3, and (ii) antigen-binding molecules capable of binding to HER3. It may include antigen-binding molecules capable of binding to antigens other than R3.

[0247] It will also be understood that antigen-binding molecules (e.g., multispecific antigen-binding molecules) according to the present invention may comprise antigen-binding polypeptides or antigen-binding polypeptide complexes capable of binding to a target for which the antigen-binding molecule is specific. For example, antigen-binding molecules according to the present invention may include, for example, (i) antigen-binding polypeptide complexes capable of binding to HER3, comprising a light chain polypeptide (comprising the structure VL-CL) and a heavy chain polypeptide (comprising the structure VH-CH1-CH2-CH3), and (ii) antigen-binding polypeptide complexes capable of binding to an antigen other than HER3, comprising a light chain polypeptide (comprising the structure VL-CL) and a heavy chain polypeptide (comprising the structure VH-CH1-CH2-CH3).

[0248] In some embodiments, an antigen-binding molecule that is a component of a larger antigen-binding molecule (e.g., a multispecific antigen-binding molecule) may be referred to as, for example, an "antigen-binding domain" or "antigen-binding region" of the larger antigen-binding molecule.

[0249] In some embodiments, the antigen-binding molecule comprises an antigen-binding molecule capable of binding to HER3 and an antigen-binding molecule capable of binding to an antigen other than HER3. In some embodiments, the antigen other than HER3 is a surface molecule of an immune cell. In some embodiments, the antigen other than HER3 is a cancer cell antigen. In some embodiments, the antigen other than HER3 is a receptor molecule, e.g., a cell surface receptor. In some embodiments, the antigen other than HER3 is a cell signaling molecule, e.g., a cytokine, chemokine, interferon, interleukin, or lymphokine. In some embodiments, the antigen other than HER3 is a growth factor or hormone.

[0250] A cancer cell antigen is an antigen that is expressed or overexpressed by cancer cells. A cancer cell antigen can be any peptide / polypeptide, glycoprotein, lipoprotein, glycan, glycolipid, lipid, or fragment thereof. Expression of a cancer cell antigen can be associated with cancer. A cancer cell antigen can be aberrantly expressed by cancer cells (e.g., the cancer cell antigen can be expressed with abnormal localization) or with abnormal structure by cancer cells. A cancer cell antigen can be capable of eliciting an immune response. In some embodiments, the antigen is expressed on the cell surface of cancer cells (i.e., the cancer cell antigen is a cancer cell surface antigen). In some embodiments, the portion of the antigen that is bound by the antigen-binding molecule of the present invention is displayed on the external surface of the cancer cell (i.e., is extracellular). A cancer cell antigen can be a cancer-associated antigen. In some embodiments, a cancer cell antigen is an antigen whose expression is associated with the onset, progression, or severity of symptoms of cancer. Cancer-associated antigens may be associated with the cause or pathology of cancer, or may be aberrantly expressed as a consequence of cancer. In some embodiments, a cancer cell antigen is an antigen whose expression is upregulated (e.g., at the RNA level and / or protein level) by cancer cells, e.g., compared to the expression level by comparable non-cancerous cells (e.g., non-cancerous cells derived from the same tissue / cell type). In some embodiments, a cancer-associated antigen may be preferentially expressed by cancerous cells and not expressed by comparable non-cancerous cells (e.g., non-cancerous cells derived from the same tissue / cell type). In some embodiments, a cancer-associated antigen may be the product of a mutated oncogene or a mutated tumor suppressor gene. In some embodiments, a cancer-associated antigen may be the product of an overexpressed intracellular protein, a cancer antigen produced by an oncogenic virus, an oncofetal antigen, or a cell surface glycolipid or glycoprotein.

[0251] In some embodiments, the antigen other than HER3 is an antigen expressed by cells of a HER3-associated cancer. A HER3-associated cancer expresses HER3 (e.g., on the cell surface). The cancer may be a HER3-positive cancer (expressing the HER3 protein); such cancers may be referred to as "HER3-positive" cancers. HER3-associated cancers include cancers in which expression of the HER3 gene / protein is a risk factor and / or is positively associated with cancer occurrence, development, progression, or symptom severity, and / or metastasis. HER3-associated cancers include those described in Zhang et al., Acta Biochimica et Biophysica Sinica (2016), 48(1):39-48; and Sithanandam and Anderson Cancer Gene Ther (2008), 15(7):413-448, all of which are incorporated herein by reference in their entireties. In some embodiments, the HER3-associated cancer may be lung cancer (e.g., NSCLC), melanoma, breast cancer, pancreatic cancer, prostate cancer, ovarian cancer, gastric cancer, colon cancer, or oral cancer.

[0252] The immune cell surface molecule can be any peptide / polypeptide, glycoprotein, lipoprotein, glycan, glycolipid, lipid, or fragment thereof expressed on the cell surface of the immune cell or on the cell surface. In some embodiments, the portion of the immune cell surface molecule bound by the antigen-binding molecule of the present invention is on the external surface of the immune cell (i.e., extracellular). The immune cell surface molecule can be expressed on the cell surface of any immune cell. In some embodiments, the immune cell can be a cell of hematopoietic origin, such as a neutrophil, eosinophil, basophil, dendritic cell, lymphocyte, or monocyte. The lymphocyte can be, for example, a T cell, a B cell, a natural killer (NK) cell, a NKT cell, or an innate lymphoid cell (ILC), or a precursor cell thereof (e.g., a thymocyte or a pre-B cell). In some embodiments, the immune cell surface molecule can be a costimulatory molecule (e.g., CD28, OX40, 4-1BB, ICOS, or CD27) or a ligand thereof. In some embodiments, the immune cell surface molecule can be a checkpoint molecule (e.g., PD-1, CTLA-4, LAG-3, TIM-3, VISTA, TIGIT, or BTLA) or a ligand thereof.

[0253] Multispecific antigen-binding molecules according to the invention can be provided in any suitable format, such as those described in Brinkmann and Kontermann, MAbs (2017), 9(2):182-212, which is incorporated herein by reference in its entirety. Suitable formats include those shown in Figure 2 of Brinkmann and Kontermann, MAbs (2017), 9(2):182-212: antibody conjugates, e.g., IgG2, F(ab')2, or CovX-Body; IgG or IgG-like molecules, e.g., common HC of IgG, chimeric IgG, κλ-body; CH1 / CL fusion proteins, e.g., scFv2-CH1 / CL, VHH2-CH1 / CL; "Variable domain only" bispecific antigen-binding molecules, e.g., tandem scFv (taFv), triple body, diabody (Db), dsDb, Db(kih), DART, scDB, dsFv-dsFv, tandAb, triple head, tandem dAb / VHH, tetravalent dAb.VHH; non-Ig fusion proteins, e.g., scFv2-albumin, scDb-albumin, taFv-albumin, taFv-toxin, miniantibodies, DNL- Fab2, DNL-Fab2-scFv, DNL-Fab2-IgG-cytokine 2, ImmTAC (TCR-scFv); modified Fc / CH3 fusion proteins, such as scFv-Fc(kih), scFv-Fc(CH3 charge pair), scFv-Fc(EW-RVT), scFv-fc(HA-TF), scFv-Fc(SEEDbody), taFv-Fc(kih), scFv-Fc(kih)-Fv, Fab-Fc(kih)-s cFv, Fab-scFv-Fc(kih), Fab-scFv-Fc(BEAT), Fab-scFv-Fc(SEEDbody), DART-Fc, scFv-CH3(kih), TriFab; Fc fusions such as di-diabody, scDb-Fc, taFv-Fc, scFv-Fc-scFv, HCAb-VHH, Fab-scFv-Fc, scFv4-Ig, scFv2-Fcab; CH3 fusions such as dia-diabody Dee, scDb-CH3; IgE / IgM CH2 fusions, e.g., scFv-EHD2-scFv, scFvMHD2-scFv; Fab fusion proteins, e.g., Fab-scFv (bibody), Fab-scFv2 (tribody), Fab-Fv, Fab-dsFv, Fab-VHH, orthogonal Fab-Fab; non-Ig fusion proteins, e.g., DNL-Fab3, DNL-Fab2-scFv, DNL-Fab2-IgG-cytokine2; asymmetric IgG or IgG-like molecules, e.g., IgG(kih), IgG(kih) common LC, ZW1 IgG common LC, Biclonics common LC, CrossMab, CrossMab(kih), scFab-IgG(kih), Fab-scFab-IgG(kih), orthogonal Fab IgG(kih), DuetMab, CH3 charge pair + CH1 / CL charge pair, hinge / CH3 charge pair, SEED-body, duobody, four-in-one-CrossMab(kih), LUZ-Y common LC; LUZ-Y scFab-IgG, FcFc *appended / Fc-modified IgG, such as IgG(kih)-Fv, IgG HA-TF-Fv, IgG(kih)scFab, scFab-Fc(kih)-scFv2, scFab-Fc(kih)-scFv, half DVD-Ig, DVI-Ig(four-in-one), CrossMab-Fab; modified Fc / CH3 fusion proteins, such as Fab-Fc(kih)-scFv, Fab-scFv-Fc(kih), Fab-scFv-Fc(BEAT), Fab-scFv-Fc-SEEDbody, TriFab; appended IgG-HC fusions, such as IgG-HC, scFv, IgG-dAb, IgG-taFV, IgG-CrossFab, IgG-orthogonal Fab, IgG-(CαCβ)Fab, scFv-HC-IgG, tandem Fab-IgG (orthogonal Fab) Fab-IgG(CαCβ) Fab), Fab-IgG(CR3), Fab-hinge-IgG(CR3); appended IgG-LC fusions, e.g., IgG-scFv(LC), scFv(LC)-IgG, dAb-IgG; appended IgG-HC / LC fusions, e.g., DVD-Ig, TVD-Ig, CODV-Ig, scFv4-IgG, Zybody; Fc fusions, e.g., Fab-scFv-Fc, scFv4-Ig; F(ab')2 fusions, e.g., F(ab')2-scFv2; CH1 / CL fusion proteins, e.g., scFv2-CH1-hinge / CL; modified IgGs, e.g., DAF (two-in-one-IgG), DutaMab, Mab 2 and non-Ig fusions, such as DNL-Fab4-IgG.

[0254] Those skilled in the art can design and prepare bispecific antigen-binding molecules. Methods for producing bispecific antigen-binding molecules include chemically crosslinking antigen-binding molecules or antibody fragments, for example, via a reducible disulfide bond or a non-reducible thioether bond, as described, for example, in Segal and Bast, 2001, "Production of Bispecific Antigen-binding Molecules," Current Protocols in Immunology, 14:IV:2.13:2.13.1-2.13.16, which is incorporated herein by reference in its entirety. For example, N-succinimidyl-3-(-2-pyridyldithio)-propionate (SPDP) can be used to chemically crosslink Fab fragments, for example, via SH groups in the hinge region, to create disulfide-linked, bispecific F(ab)2 heterodimers.

[0255] Another method for producing bispecific antigen-binding molecules is to fuse antibody-producing hybridomas, for example with polyethylene glycol, as described, e.g., in DM and Bast, BJ, 2001, "Production of Bispecific Antigen-binding Molecules," Current Protocols in Immunology, Vol. 1, No. 1, pp. 111-114, 2001. The method includes the step of generating quadroma cells capable of secreting bispecific antibodies, as described in "In Immunology," 14:IV:2.13:2.13.1 to 2.13.16.

[0256] Bispecific antigen-binding molecules according to the present invention may also be produced by recombinant expression from nucleic acid constructs encoding polypeptides for the antigen-binding molecules, e.g., as described in "Antibody Engineering: Methods and Protocols", 2nd Edition (Humana Press, 2012), Chapter 40: "Production of Bispecific Antigen-binding Molecules: Diabodies and Tandem scFv" (Hornig and Faerber-Schwarz); or French, "How to make bispecific antigen-binding molecules", Methods Mol. Med., 2000, 40:333-339, the entire contents of both of which are incorporated herein by reference. For example, a DNA construct encoding the light and heavy chain variable domains for two antigen-binding fragments (i.e., the light and heavy chain variable domains for the antigen-binding fragment capable of binding to HER3, and the light and heavy chain variable domains for the antigen-binding fragment capable of binding to another target protein), and including sequences encoding a suitable linker or dimerization domain between the antigen-binding fragments, can be prepared by molecular cloning methods. Recombinant bispecific antibodies can then be produced by expression (e.g., in vitro) of the construct in suitable host cells (e.g., mammalian host cells), and the expressed recombinant bispecific antibodies can then, optionally, be purified. Fc area In some embodiments, the antigen-binding molecules of the invention comprise an Fc region.

[0257] In IgG, IgA, and IgD isotypes, the Fc region is composed of a CH2 and CH3 region derived from one polypeptide and a CH2 and CH3 region derived from another polypeptide. The CH2 and CH3 regions derived from the two polypeptides together form the Fc region. In IgM and IgE isotypes, the Fc region contains three constant domains (CH2, CH3, and CH4), and the CH2 to CH4 regions derived from the two polypeptides together form the Fc region.

[0258] In preferred embodiments according to various aspects of the present disclosure, the Fc region comprises two polypeptides, each polypeptide comprising a CH2 region and a CH3 region.

[0259] In some embodiments, the antigen-binding molecules of the present invention comprise an Fc region containing modifications in one or more of the CH2 and CH3 regions that promote Fc region assembly. Recombinant coexpression of constituent polypeptides of an antigen-binding molecule and subsequent assembly results in several possible combinations. To improve the yield of a desired combination of polypeptides within an antigen-binding molecule during recombinant production, it is advantageous to introduce a modification(s) in the Fc region that promotes the assembly of a desired combination of heavy chain polypeptides. Modifications may, for example, promote hydrophobic and / or electrostatic interactions between the CH2 and / or CH3 regions of different polypeptide chains. Suitable modifications are described, for example, in Ha et al., Front. Immunol (2016), 7:394, incorporated herein by reference in its entirety.

[0260] In some embodiments, the antigen-binding molecules of the invention are in the following formats: KiH, KiH, as shown in Table 1 of Ha et al., Front. Immunol (2016), 7:394. S-S , HA-TF, ZW1, 7.8.60, DD-KK, EW-RVT, EW-RVT S-S , SEED, or A107.

[0261] In some embodiments, the Fc region may be selected from the group consisting of those described in, e.g., US 7,695,936; and Carter, J Immunol Meth, 248, 7-15 (2001). In such embodiments, one of the CH3 regions of the Fc region contains a "knob-into-hole (KIH)" or "KiH" modification. In such embodiments, one of the CH3 regions contains a "knob" modification and the other CH3 region contains a "hole" modification. The "knob" and "hole" modifications are placed within each CH3 region such that the "knob" is placed within the "hole" to promote heterodimerization (and inhibit homodimerization) of the polypeptides and / or stabilize the heterodimer. Knobs are constructed by substituting amino acids with larger side chains (e.g., tyrosine or tryptophan). Holes are created by substituting amino acids with smaller side chains (e.g., alanine or threonine).

[0262] In some embodiments, one of the CH3 regions of the Fc region of the antigen-binding molecule of the present invention is a substitution. (The numbering of positions / substitutions of the Fc, CH2, and CH3 regions herein is based on Kabat et al., "Sequences of Proteins of Immunological Interest," 5th ed., Public Health In some embodiments, one of the CH3 regions of the Fc region of the antigen-binding molecule comprises the substitution T366W (according to the EU numbering system as described in the Fc Regions of the National Institutes of Health, Bethesda, MD, 1991), and the other CH3 region of the Fc region comprises the substitution Y407V. In some embodiments, one of the CH3 regions of the Fc region of the antigen-binding molecule comprises the substitution T366W, and the other CH3 region of the Fc region comprises the substitutions T366S and L368A. In some embodiments, one of the CH3 regions of the Fc region of the antigen-binding molecule comprises the substitution T366W, and the other CH3 region of the Fc region comprises the substitutions Y407V, T366S, and L368A.

[0263] In some embodiments, the Fc region comprises a "DD-KK" modification, e.g., as described in WO2014 / 131694A1. In some embodiments, one of the CH3 regions comprises substitutions K392D and K409D, and the other CH3 region of the Fc region comprises substitutions E356K and D399K. The modifications promote electrostatic interactions between the CH3 regions.

[0264] In some embodiments, the antigen-binding molecules of the present invention comprise Fc regions modified as described in Labrijn et al., Proc Natl Acad Sci USA. (2013), 110(13):5145-50, referred to as a "duobody" format. In some embodiments, one of the CH3 regions comprises the substitution K409R, and the other CH3 region of the Fc region comprises the substitution K405L.

[0265] In some embodiments, antigen-binding molecules of the invention comprise an Fc region containing the "EEE-RRR" modification described in Strop et al., J Mol Biol. (2012), 420(3):204-19. In some embodiments, one of the CH3 regions comprises the substitutions D221E, P228E, and L368E, and the other CH3 region of the Fc region comprises the substitutions D221R, P228R, and K409R.

[0266] In some embodiments, the antigen-binding molecule comprises an Fc region comprising the "EW-RVT" modification described in Choi et al., Mol Cancer Ther (2013), 12(12):2748-59. In some embodiments, one of the CH3 regions comprises the substitutions K360E and K409W, and the other CH3 region of the Fc region comprises the substitutions Q347R, D399V, and F405T.

[0267] In some embodiments, one of the CH3 regions contains the substitution S354C, and the other CH3 region of the Fc region contains the substitution Y349C. The introduction of these cysteine ​​residues also results in the formation of a disulfide bridge between the two CH3 regions of the Fc region. This further stabilizes the heterodimer (Carter (2001), J Immunol Methods, 248, 7-15).

[0268] In some embodiments, the Fc region is S-S In some embodiments, one of the CH3 regions includes the substitutions T366W and S354C, and the other CH3 region of the Fc region includes the substitutions T366S, L368A, Y407V, and Y349C.

[0269] In some embodiments, the antigen-binding molecules of the invention comprise an Fc region comprising the "SEED" modification, in which the β-strand segment of human IgG1 CH3 is swapped for the β-strand segment of human IgA CH3, as described by Davis et al., Protein Eng Des Sel (2010), 23(4):195-202.

[0270] In some embodiments, one of the CH3 regions contains the substitutions S364H and F405A, and the other CH3 region of the Fc region contains the substitutions Y349T and T394F (see, e.g., Moore et al., MAbs (2011), 3(6):546-57).

[0271] In some embodiments, one of the CH3 regions contains the substitutions T350V, L351Y, F405A, and Y407V, and the other CH3 region of the Fc region contains the substitutions T350V, T366L, K392L, and T394W (see, e.g., Von Kreudenstein et al., MAbs (2013), 5(5):646-54).

[0272] In some embodiments, one of the CH3 regions includes the substitutions K360D, D399M, and Y407A, and the other CH3 region of the Fc region includes the substitutions E345R, Q347R, T366V, and K409V (see, e.g., Leaver-Fay et al., Structure (2016), 24(4):641-51).

[0273] In some embodiments, one of the CH3 regions contains the substitutions K370E and K409W, and the other CH3 region of the Fc region contains the substitutions E357N, D399V, and F405T (see, e.g., Choi et al., PLoS One (2015), 10(12):e0145349).

[0274] Fc-mediated functions include binding to Fc receptors, antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cell-mediated phagocytosis (ADCP), complement-dependent cytotoxicity (CDC), formation of the membrane attack complex (MAC), cellular degranulation, cytokine and / or chemokine production, and antigen processing and presentation.

[0275] Modifications to the Fc region of antibodies that affect Fc-mediated functions are known in the art, such as those described in Wang et al., Protein Cell (2018), 9(1):63-73, which is incorporated herein by reference in its entirety. Exemplary Fc region modifications known to affect antibody effector function are summarized in Table 1 of Wang et al., Protein Cell (2018), 9(1):63-73.

[0276] The substitution combination F243L / R292P / Y300L / V305I / P396L has been described in Stavenhagen et al., Cancer Res. (2007) to increase binding to FcγRIIIa, thereby enhancing ADCC. The substitution combinations S239D / I332E or S239D / I332E / A33 Substitution combination S239D / I332E / A330L has been described in Lazar et al., Proc Natl Acad Sci USA. (2006), 103:4005-4010, to increase binding to FcγRIIIa, thereby increasing ADCC. Substitution combination S239D / I332E / A330L has also been described to decrease binding to FcγRIIb, thereby increasing ADCC. Substitution combination S298A / E333A / K334A has been described in Shields et al., J Biol Chem. (2001), 276:6591-6604, to increase binding to FcγRIIIa, thereby increasing ADCC. The substitution combination L234Y / L235Q / G236W / S239M / H268D / D270E / S298A in one heavy chain and the substitution combination D270E / K326D / A330M / K334E in the other heavy chain have been described in Mimoto et al., MAbs. (2013):5:229-236, as increasing FcγRIIIa binding and thereby increasing ADCC. The substitution combination G236A / S239D / I332E has been described in Richards et al., Mol Cancer Ther. (2008)7:2517-2527, as increasing FcγRIIa binding and increasing FcγRIIIa binding and thereby increasing ADCC.

[0277] The substitution combination K326W / E333S has been described in Idusogie et al., J Immunol. (2001), 166(4):2571-5, to increase binding to C1q, thereby increasing CDC. The substitution combination S267E / H268F / S324T has been described in Moore et al., MAbs. (2010), 2(2):181-9, to increase binding to C1q, thereby increasing CDC. The substitution combination described in Natsume et al., Cancer Res. (2008), 68(10):3863-72 has been reported to increase binding to C1q, thereby increasing CDC. The substitution combination E345R / E430G / S440Y has been described in Diebolder et al., Science (2014), 343(6176):1260-3 to increase binding to hexamerization and thereby increase CDC.

[0278] The substitution combination M252Y / S254T / T256E has been reported in Dall'Acqua et al., J Immunol. (2002), 169:5171-5180, to increase FcRn binding at pH 6.0, thereby extending the half-life of antigen-binding molecules. The substitution combination M428L / N434S has been reported in Zalevsky et al., Nat Biotechnol. (2010), 28:157-159, to increase FcRn binding at pH 6.0, thereby extending the half-life of antigen-binding molecules.

[0279] When a heavy chain constant region / Fc region / CH2-CH3 region / CH2 region / CH3 region is described herein as containing position(s) / substitution(s) "corresponding to" referenced position(s) / substitution(s), the equivalent position(s) / substitution(s) in a homologous heavy chain constant region / Fc region / CH2-CH3 region / CH2 region / CH3 region is envisioned.

[0280] When an Fc region is described as comprising specific position(s) / substitution(s), the position(s) / substitution(s) may be present in one or both of the polypeptide chains that together form the Fc region.

[0281] Unless otherwise specified, locations herein are taken from Kabat et al., "Sequences of Proteins of Immunological Interest," 5th ed., Public Health Service, National It refers to the positions of the amino acid sequence of a human immunoglobulin constant region, numbered according to the EU numbering system, as set forth by the Institutes of Health, Bethesda, MD, 1991. By way of example, the substitutions L242C and K334C in human IgG1 correspond to the L→C substitution at position 125 and the K→C substitution at position 217 of the human IgG1 constant region, numbered according to SEQ ID NO:171.

[0282] A homologous heavy chain constant region is a heavy chain constant region comprising an amino acid sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the heavy chain constant region of human IgG1 (i.e., the amino acid sequence set forth in SEQ ID NO: 171). A homologous Fc region is an Fc region composed of a polypeptide comprising an amino acid sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the CH2-CH3 region of human IgG1 (i.e., the amino acid sequence set forth in SEQ ID NOs: 174 and 175). A homologous CH2 region is a CH2 region comprising an amino acid sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the CH2 region of human IgG1 (i.e., the amino acid sequence set forth in SEQ ID NO: 174). A homologous CH3 region is a CH3 region comprising an amino acid sequence having at least 60%, preferably 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the CH3 region of human IgG1 (i.e., the amino acid sequence set forth in SEQ ID NO: 175).

[0283] Positions corresponding to those identified in human IgG1 can be identified by sequence alignment, which can be performed using sequence alignment software such as ClustalOmega (Soding, J. 2005, Bioinformatics, 21, 951-960).

[0284] In some embodiments, antigen-binding molecules of the present invention comprise an Fc region comprising a modification that increases an Fc-mediated function. In some embodiments, the Fc region comprises a modification that increases ADCC. In some embodiments, the Fc region comprises a modification that increases ADCP. In some embodiments, the Fc region comprises a modification that increases CDC. Antigen-binding molecules comprising an Fc region comprising a modification that increases an Fc-mediated function (e.g., ADCC, ADCP, CDC) induce increased levels of the associated effector function compared to an antigen-binding molecule comprising a corresponding unmodified Fc region.

[0285] In some embodiments, antigen-binding molecules of the invention comprise an Fc region comprising a modification that increases affinity for one or more Fc receptors (e.g., FcγRIIa, FcγRIIIa). Modifications that increase affinity for an Fc receptor may increase Fc-mediated effector functions, such as antibody-dependent cellular cytotoxicity (ADCC) and / or antibody-dependent cellular phagocytosis (ADCP). In some embodiments, antigen-binding molecules of the invention comprise an Fc region comprising a modification that decreases affinity for C1q; such modifications decrease complement-dependent cytotoxicity (CDC), which may be desirable. In some embodiments, antigen-binding molecules of the invention comprise an Fc region comprising a modification that increases hexamer formation. Modifications to an Fc region that can increase affinity for one or more Fc receptors, decrease affinity for C1q, and / or increase hexamer formation are described, for example, in the literature, which is incorporated herein by reference in its entirety. The antigen-binding molecules of the present invention are described in Saxena and Wu, Front Immunol. (2016), 7:580, which is incorporated herein by reference. In some embodiments, the antigen-binding molecules of the present invention comprise an Fc region comprising a CH2 / CH3 that includes one or more of the substitutions set forth in Table 1 of Saxena and Wu, Front Immunol. (2016), 7:580.

[0286] In some embodiments, the antigen-binding molecules of the present invention comprise an Fc region comprising a modification that increases binding to an Fc receptor. In some embodiments, the Fc region comprises a modification that increases binding to an Fcγ receptor. In some embodiments, the Fc region comprises a modification that increases binding to one or more of FcγRI, FcγRIIa, FcγRIIb, FcγRIIc, FcγRIIIa, and FcγRIIIb. In some embodiments, the Fc region comprises a modification that increases binding to FcγRIIIa. In some embodiments, the Fc region comprises a modification that increases binding to FcγRIIa. In some embodiments, the Fc region comprises a modification that increases binding to FcγRIIb. In some embodiments, the Fc region comprises a modification that increases binding to FcRn. In some embodiments, the Fc region comprises a modification that increases binding to a complement protein. In some embodiments, the Fc region comprises a modification that increases or decreases binding to C1q. In some embodiments, the Fc region comprises a modification that promotes hexamerization of the antigen-binding molecule. In some embodiments, the Fc region comprises a modification that extends the half-life of the antigen-binding molecule. In some embodiments, the Fc region comprises a modification that increases co-engagement.

[0287] As used herein, "Fcγ receptor" can be derived from any species and can include isoforms, fragments, variants (including mutants), or homologs derived from any species. Similarly, "FcγRI," "FcγRIIa," "FcγRIIb," "FcγRIIc," "FcγRIIIa," and "FcγRIIIb" refer to FcγRI / FcγRIIa / FcγRIIb / FcγRIIc / FcγRIIIa / FcγRIIIb, respectively, derived from any species, and include isoforms, fragments, variants (including mutants), or homologs derived from any species. Humans have six distinct classes of Fcγ receptors (murine orthologs are shown in parentheses): FcγRI (mFcγRI), FcγRIIa (mFcγRIII), FcγRIIb (mFcγRIIb), FcγRIIc, FcγRIIIa (mFcγRIV), and FcγRIIIb. Mutant Fcγ receptors include, for example, the 158V and 158F polymorphisms of human FcγRIIIa and the 167H and 167R polymorphisms of human FcγRIIa.

[0288] In some embodiments, the antigen-binding molecules of the invention comprise an Fc region (e.g., further comprising a polypeptide comprising a heavy chain constant region or CH2-CH3 region) that includes one or more (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) of the following: C at position corresponding to 242; C at position corresponding to 334; A at position corresponding to 236; D at position corresponding to 239; E at position corresponding to 332; L at position corresponding to 330; K at position corresponding to 345; and G at position corresponding to 430.

[0289] In some embodiments, antigen-binding molecules of the invention comprise an Fc region (e.g., further comprising a polypeptide comprising a heavy chain constant region or CH2-CH3 regions) that comprises one or more (e.g., 1, 2, 3, 4, 5, 6, 7, or 8) of the following substitutions (or corresponding substitutions): L242C, K334C, G236A, S239D, I332E, A330L, E345K, and E430G.

[0290] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region, a CH2-CH3 region, or a further polypeptide comprising a CH2 region) a C at a position corresponding to 242. In some embodiments, the Fc region comprises: In some embodiments, the Fc region comprises a C at a position corresponding to 242 and a C at a position corresponding to 334 (e.g., comprises one further polypeptide comprising a heavy chain constant region, a CH2-CH3 region, or a CH2 region comprising these).

[0291] In some embodiments, the antigen-binding molecule comprises an Fc region that comprises an A at a position corresponding to 236 (e.g., comprises one further polypeptide that comprises a heavy chain constant region, a CH2-CH3 region, or a CH2 region comprising these). In some embodiments, the Fc region comprises a D at a position corresponding to 239 (e.g., comprises one further polypeptide that comprises a heavy chain constant region, a CH2-CH3 region, or a CH2 region comprising these). In some embodiments, the Fc region comprises an A at a position corresponding to 236 and a D at a position corresponding to 239 (e.g., comprises one further polypeptide that comprises a heavy chain constant region, a CH2-CH3 region, or a CH2 region comprising these).

[0292] In some embodiments, the antigen-binding molecule comprises an Fc region that comprises an E at a position corresponding to 332 (e.g., a heavy chain constant region, a CH2-CH3 region, or a CH2 region, including one further polypeptide). In some embodiments, the Fc region comprises an A at a position corresponding to 236, a D at a position corresponding to 239, and an E at a position corresponding to 332 (e.g., a heavy chain constant region, a CH2-CH3 region, or a CH2 region, including one further polypeptide).

[0293] In some embodiments, the antigen-binding molecule comprises an Fc region that comprises an L at a position corresponding to 330 (e.g., a heavy chain constant region, a CH2-CH3 region, or a CH2 region, comprising one or more polypeptides). In some embodiments, the Fc region comprises an A at a position corresponding to 236, a D at a position corresponding to 239, an E at a position corresponding to 332, and an L at a position corresponding to 330 (e.g., a heavy chain constant region, a CH2-CH3 region, or a CH2 region, comprising one or more polypeptides).

[0294] In some embodiments, the antigen-binding molecule comprises an Fc region that comprises a K at a position corresponding to 345 (e.g., comprises one further polypeptide that comprises a heavy chain constant region, a CH2-CH3 region, or a CH3 region comprising these). In some embodiments, the Fc region comprises a G at a position corresponding to 430 (e.g., comprises one further polypeptide that comprises a heavy chain constant region, a CH2-CH3 region, or a CH3 region comprising these). In some embodiments, the Fc region comprises a K at a position corresponding to 345 and a G at a position corresponding to 430 (e.g., comprises one further polypeptide that comprises a heavy chain constant region, a CH2-CH3 region, or a CH2 region comprising these).

[0295] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region, a CH2-CH3 region, or a further polypeptide comprising a CH2 region) a C at a position corresponding to 242, a C at a position corresponding to 334, an A at a position corresponding to 236, and a D at a position corresponding to 239.

[0296] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region, a CH2-CH3 region, or a further polypeptide comprising a CH2 region) a C at a position corresponding to 242, a C at a position corresponding to 334, an A at a position corresponding to 236, a D at a position corresponding to 239, and an E at a position corresponding to 332.

[0297] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region, a CH2-CH3 region, or a further polypeptide comprising a CH2 region) a C at a position corresponding to 242, a C at a position corresponding to 334, an A at a position corresponding to 236, a D at a position corresponding to 239, an E at a position corresponding to 332, and an L at a position corresponding to 330.

[0298] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region or a further polypeptide comprising a CH2-CH3 region) a C at a position corresponding to 242, a C at a position corresponding to 334, a K at a position corresponding to 345, and a G at a position corresponding to 430.

[0299] In some embodiments, the antigen-binding molecule comprises an Fc region that includes the substitution L242C (or an equivalent substitution) (e.g., includes one further polypeptide that includes a heavy chain constant region, a CH2-CH3 region, or a CH2 region that includes these). In some embodiments, the Fc region includes the substitution K334C (or an equivalent substitution) (e.g., includes one further polypeptide that includes a heavy chain constant region, a CH2-CH3 region, or a CH2 region that includes these). In some embodiments, the Fc region includes the substitution L242C (or an equivalent substitution) and the substitution K334C (or an equivalent substitution) (e.g., includes one further polypeptide that includes a heavy chain constant region, a CH2-CH3 region, or a CH2 region that includes these).

[0300] In some embodiments, the antigen-binding molecule comprises an Fc region that includes the substitution G236A (or an equivalent substitution) (e.g., includes one further polypeptide comprising a heavy chain constant region, a CH2-CH3 region, or a CH2 region that includes these). In some embodiments, the Fc region includes the substitution S239D (or an equivalent substitution) (e.g., includes one further polypeptide comprising a heavy chain constant region, a CH2-CH3 region, or a CH2 region that includes these). In some embodiments, the Fc region includes the substitution G236A (or an equivalent substitution) and the substitution S239D (or an equivalent substitution) (e.g., includes one further polypeptide comprising a heavy chain constant region, a CH2-CH3 region, or a CH2 region that includes these).

[0301] In some embodiments, the antigen-binding molecule comprises an Fc region that comprises the substitution I332E (or an equivalent substitution) (e.g., comprises one further polypeptide comprising a heavy chain constant region, CH2-CH3 region, or CH2 region comprising these). In some embodiments, the Fc region comprises the substitution G236A (or an equivalent substitution), the substitution S239D (or an equivalent substitution), and the substitution I332E (or an equivalent substitution) (e.g., comprises one further polypeptide comprising a heavy chain constant region, CH2-CH3 region, or CH2 region comprising these).

[0302] In some embodiments, the antigen-binding molecule comprises an Fc region (e.g., comprising one further polypeptide comprising a heavy chain constant region, CH2-CH3 region, or CH2 region comprising the substitution A330L (or an equivalent substitution). In some embodiments, the Fc region comprises (e.g., comprising one further polypeptide comprising a heavy chain constant region, CH2-CH3 region, or CH2 region comprising the substitution G236A (or an equivalent substitution), S239D (or an equivalent substitution), I332E (or an equivalent substitution), and A330L (or an equivalent substitution) substitution.

[0303] In some embodiments, the antigen-binding molecule comprises an Fc region (e.g., a heavy chain constant region, a CH2-CH3 region, or a further polypeptide comprising a CH3 region) that comprises the substitution E345K (or an equivalent substitution). In some embodiments, the Fc region comprises the substitution E430G (or an equivalent substitution) (e.g., a heavy chain constant region, a CH2-CH3 region, or a CH3 region, comprising the same, and one further polypeptide). In some embodiments, the Fc region comprises the substitution E345K (or an equivalent substitution) and the substitution E430G (or an equivalent substitution) (e.g., a heavy chain constant region, a CH2-CH3 region, or a CH2 region, comprising the same, and one further polypeptide).

[0304] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region, a CH2-CH3 region, or a further polypeptide comprising a CH2 region) the substitution L242C (or an equivalent substitution), the substitution K334C (or an equivalent substitution), the substitution G236A (or an equivalent substitution), and the substitution S239D (or an equivalent substitution).

[0305] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region, a CH2-CH3 region, or a further polypeptide comprising a CH2 region) the substitution L242C (or an equivalent substitution), the substitution K334C (or an equivalent substitution), the substitution G236A (or an equivalent substitution), the substitution S239D (or an equivalent substitution), and the substitution I332E (or an equivalent substitution).

[0306] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region, a CH2-CH3 region, or a further polypeptide comprising) the substitution L242C (or an equivalent substitution), the substitution K334C (or an equivalent substitution), the substitution G236A (or an equivalent substitution), the substitution S239D (or an equivalent substitution), the substitution I332E (or an equivalent substitution), and the substitution A330L (or an equivalent substitution).

[0307] In some embodiments, the antigen-binding molecule comprises an Fc region comprising (e.g., a heavy chain constant region or a further polypeptide comprising) the substitutions L242C (or an equivalent substitution), K334C (or an equivalent substitution), E345K (or an equivalent substitution), and E430G (or an equivalent substitution).

[0308] In some embodiments, the antigen-binding molecule contains one of the following amino acids: L at position corresponding to 243, P at position corresponding to 292, L at position corresponding to 300, I at position corresponding to 305, and L at position corresponding to 396; D at position corresponding to 239 and E at position corresponding to 332; D at position corresponding to 239, E at position corresponding to 332, and L at position corresponding to 330; A at position corresponding to 298, A at position corresponding to 333, and A at position corresponding to 334; Y at position corresponding to 234, Q at position corresponding to 235, W at position corresponding to 236, M at position corresponding to 239, D at position corresponding to 268, E at position corresponding to 270, and and A at positions corresponding to 298; E at position corresponding to 270, D at position corresponding to 326, M at position corresponding to 330, and E at position corresponding to 334; A at position corresponding to 236, D at position corresponding to 239, and E at position corresponding to 332; W at position corresponding to 326, and S at position corresponding to 333; E at position corresponding to 267, F at position corresponding to 268, and T at position corresponding to 324; R at position corresponding to 345, G at position corresponding to 430, and Y at position corresponding to 440; Y at position corresponding to 252, T at position corresponding to 254, and E at position corresponding to 256; and and one or more (e.g., 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12) of L, S at a position corresponding to position 434, and S at a position corresponding to position 434 (e.g., an Fc region including a heavy chain constant region or a CH2-CH3 region, and one polypeptide therefor).

[0309] In some embodiments, the antigen-binding molecule comprises the following combinations of substitutions (or corresponding substitutions): F243L / R292P / Y300L / V305I / P396L; S239D / I332E; S239D / I332E / A330L; S298A / E333A / K334A; L234Y / L235Q / G236W / S239M / H268D / D270E / S298A; D270E / K326D / A330M / K334E; G236A / S239D / I33 and M428L / N434S. The present invention also provides polypeptide components of antigen-binding molecules, which may be provided in isolated or substantially purified form.

[0310] The antigen-binding molecules of the present invention may be or may comprise a complex of polypeptides.

[0311] It will be understood that where a polypeptide comprises more than one domain or region, it is preferred herein that multiple domains / regions are present in the same polypeptide chain, i.e., a polypeptide comprising more than one domain or region is a fusion polypeptide comprising the domains / regions.

[0312] In some embodiments, a polypeptide in accordance with the invention comprises or consists of a VH described herein. In some embodiments, a polypeptide in accordance with the invention comprises or consists of a VL described herein.

[0313] In some embodiments, the polypeptide additionally comprises one or more heavy chain constant regions (CH) of an antibody. In some embodiments, the polypeptide additionally comprises one or more light chain constant regions (CL) of an antibody. In some embodiments, the polypeptide comprises a CH1, CH2, and / or CH3 region of an immunoglobulin (Ig).

[0314] In some embodiments, the polypeptide comprises one or more regions of an immunoglobulin heavy chain constant sequence. In some embodiments, the polypeptide comprises a CH1 region described herein. In some embodiments, the polypeptide comprises a hinge region between CH1 and CH2 described herein. In some embodiments, the polypeptide comprises a CH2 region described herein. In some embodiments, the polypeptide comprises a CH3 region described herein. In some embodiments, the polypeptide comprises a CH2-CH3 region described herein.

[0315] In some embodiments, the polypeptides have the following amino acid substitutions / combinations of amino acid substitutions (e.g., as shown in Table 1 of Ha et al., Front. Immunol (2016), 7:394, incorporated herein by reference): T366W; T366S, L368A, and Y407V; T366W and S354C; T366S, L368A, Y407V, and Y349C; S364H and F405A; Y349T and T394F; T350V, L351Y, F405A, and Y407V; T350V, T366L, K39 2L, and T394W; K360D, D399M, and Y407A; E345R, Q347R, T366V, and K409V; K409D and K392D; D399K and E356K; K360E and K409W; Q347R, D399V, and F405T; K360E, K409W, and Y349C; Q347R, D399V, F405T, and S354C; K370E and K409W; and a CH3 region comprising any one of E357N, D399V, and F405T.

[0316] In some embodiments, the CH2 and / or CH3 region of the polypeptide comprises one or more amino acid substitutions to promote association of the polypeptide with another polypeptide that comprises a CH2 and / or CH3 region.

[0317] In some embodiments, the polypeptide comprises one or more regions of an immunoglobulin light chain constant sequence, hi some embodiments, the polypeptide comprises a CL region described herein.

[0318] In some embodiments, a polypeptide in accordance with the invention comprises, from N-terminus to C-terminus, the following: (i) VH (ii) VL (iii) VH-CH1 (iv) VL-CL (v) VL-CH1 (vi) VH-CL (vii) VH-CH1-CH2-CH3 (viii) VL-CL-CH2-CH3 (ix) VL-CH1-CH2-CH3 (x)VH-CL-CH2-CH3 It contains a structure that conforms to one of the following:

[0319] The present invention also provides antigen-binding molecules composed of the polypeptides of the present invention. In some embodiments, the antigen-binding molecules of the present invention comprise a combination of the following polypeptides: (A) VH+VL (B) VH-CH1+VL-CL (C) VL-CH1+VH-CL (D) VH-CH1-CH2-CH3+VL-CL (E) VH-CL-CH2-CH3+VL-CH1 (F) VL-CH1-CH2-CH3+VH-CL (G)VL-CL-CH2-CH3+VH-CH1 (H)VH-CH1-CH2-CH3+VL-CL-CH2-CH3 (I)VH-CL-CH2-CH3+VL-CH1-CH2-CH3 Contains one of the following:

[0320] In some embodiments, an antigen-binding molecule comprises more than one of the polypeptide combinations set forth in (A)-(I) above. By way of example, and referring to (D) above, in some embodiments, an antigen-binding molecule comprises two polypeptides comprising the structure VH-CH1-CH2-CH3 and two polypeptides comprising the structure VL-CL.

[0321] In some embodiments, the antigen-binding molecules of the invention comprise a combination of the following polypeptides: (J) VH (anti-HER3) + VL (anti-HER3) (K)VH(anti-HER3)-CH1+VL(anti-HER3)-CL (L)VL(anti-HER3)-CH1+VH(anti-HER3)-CL (M)VH(anti-HER3)-CH1-CH2-CH3+VL(anti-HER3)-CL (N)VH(anti-HER3)-CL-CH2-CH3+VL(anti-HER3)-CH1 (O)VL(anti-HER3)-CH1-CH2-CH3+VH(anti-HER3)-CL (P)VL(anti-HER3)-CL-CH2-CH3+VH(anti-HER3)-CH1 (Q)VH(anti-HER3)-CH1-CH2-CH3+VL(anti-HER3)-CL-CH2-CH3 (R)VH(anti-HER3)-CL-CH2-CH3+VL(anti-HER3)-CH1-CH2-CH3 where "VH(anti-HER3)" refers to the VH of an antigen-binding molecule capable of binding to HER3 as described herein, for example, as defined in one of (1) to (61) above; and "VL(anti-HER3)" refers to the VL of an antigen-binding molecule capable of binding to HER3 as described herein, for example, as defined in one of (62) to (119) above.

[0322] In some embodiments, the polypeptide comprises or consists of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NOs: 187-223. Linkers and further sequences In some embodiments, the antigen-binding molecules and polypeptides of the present invention comprise a hinge region. In some embodiments, the hinge region is provided between the CH1 region and the CH2 region. In some embodiments, the hinge region is provided between the CL region and the CH2 region. In some embodiments, the hinge region comprises or consists of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 173.

[0323] In some embodiments, the antigen-binding molecules and polypeptides of the present invention comprise one or more linker sequences between amino acid sequences, which may be provided at one or both ends of one or more of the VH, VL, hinge region between CH1 and CH2, CH2 region, and CH3 region of the antigen-binding molecule / polypeptide.

[0324] Linker sequences are known to those skilled in the art and are described, for example, in Chen et al., Adv Drug Deliv Rev (2013), 65(10):1357-1369, which is incorporated herein by reference in its entirety. In some embodiments, the linker sequence may be a flexible linker sequence. A flexible linker sequence allows relative movement of the amino acid sequences connected by the linker sequence. Linker sequences are known to those skilled in the art, and several linker sequences are identified in Chen et al., Adv Drug Deliv Rev (2013), 65(10):1357-1369. Flexible linker sequences often contain a high proportion of glycine and / or serine residues.

[0325] In some embodiments, the linker sequence comprises at least one glycine residue and / or at least one serine residue. In some embodiments, the linker sequence consists of glycine and serine residues. In some embodiments, the linker sequence has a length of 1 to 2, 1 to 3, 1 to 4, 1 to 5, or 1 to 10 amino acids.

[0326] The antigen-binding molecules and polypeptides of the present invention may additionally comprise additional amino acids or amino acid sequences. For example, the antigen-binding molecules and polypeptides may be modified to facilitate the expression, folding, trafficking, processing, purification, and / or purification of the antigen-binding molecules / polypeptides. or may comprise an amino acid sequence(s) that facilitates detection. For example, antigen-binding molecules / polypeptides may optionally comprise a sequence encoding His (e.g., 6xHis), Myc, GST, MBP, FLAG, HA, E, or a biotin tag at the N- or C-terminus of the antigen-binding molecule / polypeptide. In some embodiments, antigen-binding molecules / polypeptides comprise a detection moiety, such as a fluorescent, luminescent, immunodetectable, radioactive, chemical, nucleic acid, or enzymatic label.

[0327] The antigen-binding molecules and polypeptides of the present invention may additionally contain a signal peptide (also known as a leader sequence or signal sequence). A signal peptide usually consists of a sequence of 5 to 30 hydrophobic amino acids that forms a single alpha helix. Proteins that are secreted and expressed on the cell surface often contain a signal peptide.

[0328] A signal peptide can be present at the N-terminus of an antigen-binding molecule / polypeptide and can be present in a newly synthesized antigen-binding molecule / polypeptide. The signal peptide ensures efficient trafficking and secretion of the antigen-binding molecule / polypeptide. The signal peptide is often removed by cleavage and is therefore not included in the mature antigen-binding molecule / polypeptide secreted from cells expressing the antigen-binding molecule / polypeptide.

[0329] Signal peptides are known for many proteins and are recorded in databases such as GenBank, UniProt, Swiss-Prot, TrEMBL, Protein Information Resource, Protein Data Bank, Ensembl, and InterPro, and / or can be identified / predicted using amino acid sequence analysis tools such as, for example, SignalP (Petersen et al., 2011, Nature Methods, 8:785-786) or Signal-BLAST (Frank and Sippl, 2008, Bioinformatics, 24:2172-2176).

[0330] In some embodiments, the signal peptide of an antigen-binding molecule / polypeptide of the present invention comprises or consists of an amino acid sequence having at least 80%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the amino acid sequence of one of SEQ ID NOs: 178-186. Labels and conjugates In some embodiments, the antigen-binding molecules of the invention additionally comprise a detectable moiety.

[0331] In some embodiments, the antigen-binding molecule comprises a detectable moiety, such as a fluorescent label, a phosphorescent label, a luminescent label, an immunodetectable label (e.g., an epitope tag), a radioactive label, a chemical label, a nucleic acid label, or an enzymatic label. The antigen-binding molecule may be covalently or non-covalently labeled with the detectable moiety.

[0332] Fluorescent labels include, for example, fluorescein, rhodamine, allophycocyanin, eosin, and NDB, green fluorescent protein (GFP), rare earth chelators such as europium (Eu), terbium (Tb), and samarium (Sm), tetramethylrhodamine, Texas Red, 4-methylumbelliferone, 7-amino-4-methylcoumarin, Cy3, and Cy5. Radioactive labels include iodine 123 , iodine 125 , iodine 126 , iodine 131 , iodine 133 ,bromine 77 , technetium 99m ,indium 111 ,indium 113m ,gallium 67 ,gallium 68 ,ruthenium 95 ,ruthenium 97 ,ruthenium 103 ,ruthenium 105 ,mercury 207 ,mercury 203 ,rhenium 99m ,rhenium 1 01 ,rhenium 105 ,scandium 47 , tellurium 121m , tellurium 122m , tellurium 125m ,thulium 165 ,thulium 167 ,thulium 168 ,copper 67 , fluorine 18 ,yttrium90 ,palladium 100 , bismuth 217 , and antimony 211 Examples of suitable labels include radioisotopes such as fluorophore, ...

[0333] In some embodiments, the antigen-binding molecules of the present invention are conjugated to a chemical moiety. The chemical moiety can be a moiety for providing a therapeutic effect. Antibody-drug conjugates are reviewed, for example, in Parslow et al., Biomedicines, September 2016, 4(3):14. In some embodiments, the chemical moiety can be a drug moiety (e.g., a cytotoxic agent). In some embodiments, the drug moiety can be a chemotherapeutic agent. In some embodiments, the drug moiety is selected from calicheamicin, DM1, DM4, monomethyl auristatin E (MMAE), monomethyl auristatin F (MMAF), SN-38, doxorubicin, duocarmycin, D6.5, and PBD. Specific Exemplary Embodiments of Antigen-Binding Molecules In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 187; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 188. It comprises or consists of:

[0334] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 189; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 190. It comprises or consists of:

[0335] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 191; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 192. It comprises or consists of:

[0336] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 193; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 195. It comprises or consists of:

[0337] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 194; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 195. It comprises or consists of:

[0338] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 196; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 195. It comprises or consists of:

[0339] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 197; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 199. It comprises or consists of:

[0340] In some embodiments, the antigen-binding molecule is (i) an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 198; two polypeptides comprising or consisting of the amino acid sequence; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 199. It comprises or consists of:

[0341] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 200; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 201. It comprises or consists of:

[0342] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 202; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 203. It comprises or consists of:

[0343] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 204; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 205. It comprises or consists of:

[0344] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 206; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 207. It comprises or consists of:

[0345] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 208; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 209. It comprises or consists of:

[0346] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 210; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 211. It comprises or consists of:

[0347] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 212; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 213. It comprises or consists of:

[0348] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 214; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 215. It comprises or consists of:

[0349] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 216; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 217. It comprises or consists of:

[0350] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 218; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 219. It comprises or consists of:

[0351] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 220; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 221. It comprises or consists of:

[0352] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 222; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 223. It comprises or consists of:

[0353] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 225; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 207. It comprises or consists of:

[0354] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 226; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 207. It comprises or consists of:

[0355] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 227; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 217. It comprises or consists of:

[0356] In some embodiments, the antigen-binding molecule is (i) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 228; and (ii) two polypeptides comprising or consisting of an amino acid sequence having at least 70%, preferably 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% amino acid sequence identity to the amino acid sequence of SEQ ID NO: 217. It comprises or consists of: Functional properties of antigen-binding molecules The antigen-binding molecules described herein can be characterized by reference to certain functional properties. In some embodiments, the antigen-binding molecules described herein have the following properties: binding to HER3 (e.g., human, mouse, rat, or cynomolgus monkey HER3); lack of binding to EGFR and / or HER2; binding to HER3-expressing cells; binding to subdomain II of the extracellular region of HER3; binding to HER3 when HER3 is in the open and closed conformations; Binding to HER3 in an NRG-independent manner; does not compete with MM-121 and / or LJM-716 for binding to HER3; does not compete with M-05-74 and / or M-08-11 for binding to HER3; Inhibits the interaction of HER3 with its interacting partners (e.g., HER3, HER2, EGFR, HER4, HGFR, IGF1R, and / or cMet) thing; inhibiting HER3-mediated signaling; inhibiting proliferation of HER3-expressing cells (e.g., in response to stimulation with NRG); inhibiting PI3K / AKT / mTOR and / or MAPK signaling in HER3-expressing cells (e.g., in response to stimulation with NRG); binding to activating Fcγ receptors (e.g., FcγRIIIa); increased binding to activating Fcγ receptors; enhanced binding to activating Fcγ receptors compared to a comparable antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequences of SEQ ID NOs: 174-175; reduced binding to inhibitory Fcγ receptors compared to a comparable antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequences of SEQ ID NOs: 174-175; increased binding to activating Fcγ receptors over binding to inhibitory Fcγ receptors compared to a comparable antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequences of SEQ ID NOs: 174-175; Increased or decreased binding to complement proteins (e.g., C1q) compared to an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175; Increased hexamerization compared to a comparable antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175; Increased ADCC activity compared to an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequences of SEQ ID NOs: 174-175; Increased ADCP activity compared to an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175; Increased or decreased CDC activity compared to an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175; Similar or increased thermal stability compared to an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175; increasing the killing of HER3-expressing cells; Reducing the number / proportion of HER3-expressing cells; and Inhibiting cancer development and / or progression in vivo may possess one or more of:

[0357] The antigen-binding molecules described herein preferably exhibit specific binding to HER3. As used herein, "specific binding" refers to binding that is selective for an antigen and can be distinguished from non-specific binding to non-target antigens. An antigen-binding molecule that specifically binds to a target molecule preferably binds to the target with greater affinity and / or longer duration than when it binds to other non-target molecules.

[0358] The ability of a given polypeptide to specifically bind to a given molecule can be determined by analysis according to methods known in the art, such as ELISA, surface plasmon resonance (SPR; see, e.g., Hearty et al., Methods Mol Biol (2012), 907:411-442), biolayer interferometry (see, e.g., Lad et al. (2015), J Biomol Screen, 20(4):498-507), flow cytometry, or radiolabeled antigen binding assay (RIA), enzyme-linked immunosorbent assay. By such analysis, binding to a given molecule can be measured and quantified. In some embodiments, binding can be a response detected in a given assay.

[0359] In some embodiments, the degree of binding of an antigen-binding molecule to a non-target molecule can be measured using, for example, an EL The binding specificity of an antigen-binding molecule is less than about 10% of the antibody's binding to the target molecule as measured by ISA, SPR, biolayer interferometry, or RIA. Alternatively, binding specificity can be measured by the K D by at least 0.1 orders of magnitude (i.e., 0.1 × 10 n where n is an integer representing the number of digits]) D ), which may optionally be at least one of 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.5, or 2.0.

[0360] In some embodiments, the antigen-binding molecules bind to human HER3, mouse HER3, rat HER3, and / or cynomolgus monkey (Macaca fascicularis) HER3. That is, in some embodiments, the antigen-binding molecules are cross-reactive with human HER3, mouse HER3, rat HER3, and / or cynomolgus monkey HER3. In some embodiments, the antigen-binding molecules of the present invention are cross-reactive with HER3 of non-human primates. Cross-reactivity to HER3 in model species allows for testing of efficacy in in vivo syngeneic models without relying on surrogate molecules.

[0361] In some embodiments, the antigen-binding molecule binds to human HER3, mouse HER3, rat HER3, and / or cynomolgus HER3, but does not bind to HER2 and / or EGFR (eg, human HER2 and / or human EGFR).

[0362] In some embodiments, the antigen-binding molecule does not provide specific binding to EGFR (e.g., human EGFR). In some embodiments, the antigen-binding molecule does not provide specific binding to HER2 (e.g., human HER2). In some embodiments, the antigen-binding molecule does not provide specific binding to (i.e., does not cross-react with) members of the EGFR family of proteins other than HER3. In some embodiments, the antigen-binding molecule does not provide specific binding to EGFR, HER2, and / or HER4.

[0363] In some embodiments, the antigen-binding molecules of the invention have a cytotoxicity of 10 μM or less, preferably ≦5 μM, ≦2 μM, ≦1 μM, ≦500 nM, ≦400 nM, ≦300 nM, ≦200 nM, ≦100 nM, ≦95 nM, ≦90 nM, ≦85 nM, ≦80 nM, ≦75 nM, ≦70 nM, ≦65 nM, ≦60 nM, ≦55 nM, ≦50 nM, ≦45 nM, ≦40 nM, ≦35 nM, ≦30 nM, ≦25 nM, ≦20 nM, ≦15 nM, ≦12.5 nM, ≦10 nM, ≦9 nM, ≦ K of one of the following: 8nM, ≦7nM, ≦6nM, ≦5nM, ≦4nM, ≦3nM, ≦2nM, ≦1nM, ≦900pM, ≦800pM, ≦700pM, ≦600pM, ≦500pM, ≦400pM, ≦300pM, ≦200pM, ≦100pM, ≦90pM, ≦80pM, ≦70pM, ≦60pM, ≦50pM, ≦40pM, ≦30pM, ≦20pM, ≦10pM, ≦9pM, ≦8pM, ≦7pM, ≦6pM, ≦5pM, ≦4pM, ≦3pM, ≦2pM, ≦1pM D and binds to HER3 (e.g., human HER3).

[0364] The antigen-binding molecules of the present invention can bind to a specific target region of HER3. The antigen-binding region of an antigen-binding molecule according to the present invention can bind to a linear epitope of HER3 consisting of a consecutive sequence of amino acids (i.e., a primary sequence of amino acids). In some embodiments, the antigen-binding molecule can bind to a conformational epitope of HER3 consisting of a discontinuous sequence of amino acids within the amino acid sequence.

[0365] In some embodiments, the antigen-binding molecules of the present invention bind to HER3. In some embodiments, the antigen-binding molecules bind to the extracellular region of HER3 (e.g., the region set forth in SEQ ID NO: 9). In some embodiments, the antigen-binding molecules bind to a subdomain of the extracellular region of HER3. It binds to main II (for example, the region shown in SEQ ID NO: 16).

[0366] In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 229. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 229. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NOs: 230 and 231. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 230 and 231. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 230. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 230. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 231. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 231. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 23. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 23. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 21. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 21. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 19. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 19. In some embodiments, the antigen-binding molecule binds to the region of HER3 set forth in SEQ ID NO: 22. In some embodiments, the antigen-binding molecule contacts one or more amino acid residues in the region of HER3 set forth in SEQ ID NO: 22.

[0367] In some embodiments, antigen-binding molecules of the present invention are capable of binding to a polypeptide comprising or consisting of the amino acid sequence of one of SEQ ID NOs: 1, 3, 4, 6, or 8. In some embodiments, antigen-binding molecules are capable of binding to a polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 9. In some embodiments, antigen-binding molecules are capable of binding to a polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 16. In some embodiments, antigen-binding molecules are capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 229. In some embodiments, antigen-binding molecules are capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NOs: 230 and 231. In some embodiments, antigen-binding molecules are capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 230. In some embodiments, antigen-binding molecules are capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 231. In some embodiments, antigen-binding molecules are capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 23. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 21. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 19. In some embodiments, the antigen-binding molecule is capable of binding to a peptide / polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 22.

[0368] In some embodiments, the antigen-binding molecule does not bind to the region of HER3 corresponding to positions 260-279 of SEQ ID NO: 1. In some embodiments, the antigen-binding molecule does not contact amino acid residues in the region of HER3 corresponding to positions 260-279 of SEQ ID NO: 1. In some embodiments, the antigen-binding molecule does not bind to the region of HER3 shown in SEQ ID NO: 23. In some embodiments, the antigen-binding molecule does not contact the amino acid residues in the region of HER3 set forth in SEQ ID NO: 23. In some embodiments, the antigen-binding molecule is not capable of binding to a peptide consisting of the amino acid sequence corresponding to positions 260 to 279 of SEQ ID NO: 1. In some embodiments, the antigen-binding molecule is not capable of binding to a peptide consisting of the amino acid sequence of SEQ ID NO: 23.

[0369] As used herein, "peptide" refers to a chain of two or more amino acid monomers linked by peptide bonds. Peptides are typically about 2 to 50 amino acids in length. A "polypeptide" is a polymeric chain of two or more peptides. Polypeptides are typically greater than about 50 amino acids in length.

[0370] The ability of an antigen-binding molecule to bind to a given peptide / polypeptide can be analyzed by methods well known to those skilled in the art, including ELISA, immunoblot (e.g., Western blot), immunoprecipitation, surface plasmon resonance, and biolayer interferometry.

[0371] Binding of a ligand to HER3 promotes a conformational change that allows HER3 to homodimerize or heterodimerize, resulting in activation of downstream pathways. HER3 exhibits "closed" and "open" conformations. The closed conformation means that HER3 is in a tethered conformation and is unable to bind due to receptor homodimerization or heterodimerization. The open conformation means that HER3 is in an extended conformation and is able to bind due to receptor homodimerization or heterodimerization.

[0372] In some embodiments, the antigen-binding molecule is capable of binding to HER3 when HER3 is in an open conformation. In some embodiments, the antigen-binding molecule is capable of binding to HER3 when HER3 is in a closed conformation. In some embodiments, the antigen-binding molecule is capable of binding to HER3 when HER3 is in an open and / or closed conformation. In some embodiments, the antigen-binding molecule is capable of binding to the extracellular domain of HER3 when HER3 is in an open and / or closed conformation. In some embodiments, the antigen-binding molecule is capable of binding to the dimerization arm of HER3 when HER3 is in an open and / or closed conformation. Binding to the dimerization arm allows the antigen-binding molecule to prevent interaction of HER3 with, for example, an interaction partner of HER3 described herein.

[0373] In some embodiments, the antigen-binding molecule is capable of binding to HER3 in the presence and / or absence of a ligand for HER3. In some embodiments, the antigen-binding molecule is capable of binding to HER3 independent of a ligand for HER3. In some embodiments, the ligand is NRG, NRG-1, and / or NRG-2. HER3 is activated by binding of a ligand to its extracellular domain, which promotes a conformational change that allows HER3 to homo- or heterodimerize. Binding of the antigen-binding molecule to HER3 allows the antigen-binding molecule to inhibit the action of HER3 independent of ligand binding, both in the absence and presence of a ligand. In some embodiments, the antigen-binding molecule does not compete with a ligand for binding to HER3. In some embodiments, the antigen-binding molecule does not bind to HER3 at the ligand-binding site.

[0374] In some embodiments, the antigen-binding molecule is clone 10D1, 10D1_c75, 10D1_c76, 10D1_c77, 10D1_c78v1, 10D1_c78v In some embodiments, the antigen-binding molecule is capable of binding to the same or overlapping region of HER3 as that of an antibody comprising the VH and VL sequences of one of clones 10D1_c89, 10D1_c90, or 10D1_c91. In some embodiments, the antigen-binding molecule is capable of binding to the same region of HER3 as, or an overlapping region of HER3, bound by, an antibody comprising the VH and VL sequences of clone 10D1_c89.

[0375] The region of a peptide / polypeptide to which an antibody binds can be determined by those skilled in the art using a variety of methods known in the art, including X-ray cocrystallography of antibody-antigen complexes, peptide scanning, mutagenesis mapping, mass spectrometry hydrogen-deuterium exchange analysis, phage display, competitive ELISA, and proteolysis-based "protection" methods. Such methods are described, for example, in Gershoni et al., BioDrugs, 2007, 21(3):145-156, which is incorporated herein by reference in its entirety. Such methods can also be used to determine whether an antigen-binding molecule can bind to a protein in different conformations.

[0376] In some embodiments, the antigen-binding molecules of the invention do not bind to the same or overlapping region of HER3 as antibodies comprising the VH and VL sequences of the anti-HER3 antibody clones MM-121 (e.g., described in Schoeberl et al., Sci. Signal. (2009), 2(77):ra31) and / or LJM-716 (e.g., described in Garner et al., Cancer Res (2013), 73:6024-6035). In some embodiments, the antigen-binding molecules of the invention do not compete for binding to HER3 with antibodies comprising the VH and VL sequences of the anti-HER3 antibody clones MM-121 and / or LJM-716, as determined, for example, by SPR analysis.

[0377] In some embodiments, the antigen-binding molecules of the present invention bind to HER3 within a region accessible to antigen-binding molecules (i.e., extracellular antigen-binding molecules) when HER3 is expressed on the cell surface (i.e., in or on the cell membrane). In some embodiments, the antigen-binding molecules are capable of binding to HER3 expressed on the cell surface of HER3-expressing cells. In some embodiments, the antigen-binding molecules are capable of binding to HER3-expressing cells (e.g., HER3+ cells, e.g., HER3+ cancer cells).

[0378] The ability of an antigen-binding molecule to bind to a given cell type can be analyzed, for example, by contacting the cells with the antigen-binding molecule and detecting the antigen-binding molecule bound to the cells, after a washing step to remove unbound antigen-binding molecules. The ability of an antigen-binding molecule to bind to immune cell surface molecule-expressing cells and / or cancer cell antigen-expressing cells can be analyzed by methods such as flow cytometry and immunofluorescence microscopy.

[0379] The antigen-binding molecules of the present invention may be antagonists of HER3. In some embodiments, the antigen-binding molecules are capable of inhibiting a function or process (e.g., an interaction, signal transduction, or other activity) mediated by HER3 and / or a binding partner of HER3 (e.g., HER3 (i.e., in the case of homodimerization), HER2, EGFR, HER4, HGFR, IGF1R, and / or cMet). In general, "inhibition" refers to a decrease, reduction, or decrease compared to a control condition.

[0380] In some embodiments, the antigen-binding molecules of the present invention are capable of inhibiting the interaction between HER3 and its interaction partner. The HER3 interaction partner may be expressed by the same cell as HER3. The interaction partner or HER3 may be expressed on the cell surface (i.e., in or on the cell membrane). In some embodiments, the HER3 interaction partner may be a member of the EGFR family of proteins, such as HER3, HER2, EGFR, HER4, HGFR, IGF1R, and / or cMet. In some embodiments, the HER3 interaction partner may be IGF1R and / or cMet. The interaction between HER3 and its interaction partner may result in the formation of a polypeptide complex. The interaction between HER3 and its interaction partner to form a polypeptide complex may be referred to as multimerization. When multimerization is between polypeptide monomers, multimerization may be referred to as dimerization.

[0381] In some embodiments, the antigen-binding molecule is capable of inhibiting the interaction between HER3 monomers. In some embodiments, the antigen-binding molecule is capable of inhibiting the interaction between HER3 and HER2. In some embodiments, the antigen-binding molecule is capable of inhibiting the interaction between HER3 and EGFR. In some embodiments, the antigen-binding molecule is capable of inhibiting the interaction between HER3 and HER4. In some embodiments, the antigen-binding molecule is capable of inhibiting the interaction between HER3 and HGFR. In some embodiments, the antigen-binding molecule is capable of inhibiting the interaction between HER3 and IGF1R. In some embodiments, the antigen-binding molecule is capable of inhibiting the interaction between HER3 and cMet.

[0382] Inhibition of interaction can be achieved by binding of the antigen-binding molecule to a region of HER3 required for interaction between HER3 and its interaction partner (e.g., the dimerization loop of HER3 set forth in SEQ ID NO: 19). In some embodiments, the antigen-binding molecule contacts one or more residues of HER3 necessary for interaction between HER3 and its interaction partner; in this way, the antigen-binding molecule renders the region inaccessible, thereby inhibiting the interaction. In some embodiments, the antigen-binding molecule binds to HER3 in a manner that inhibits / prevents the interaction between HER3 and its interaction partner. In some embodiments, the antigen-binding molecule inhibits / blocks access of an interaction partner of HER3 to a region of HER3 required for interaction between HER3 and the interaction partner of HER3, even if the antigen-binding molecule does not contact the region of HER3 required for interaction between HER3 and the interaction partner of HER3, which may be achieved, for example, by steric blocking of access of an interaction partner of HER3 to a region of HER3 required for interaction between HER3 and the interaction partner.

[0383] In some embodiments, the antigen-binding molecule is capable of inhibiting homodimerization of HER3 monomers. In some embodiments, the antigen-binding molecule is capable of inhibiting dimerization of HER3 and HER2. In some embodiments, the antigen-binding molecule is capable of inhibiting dimerization of HER3 and EGFR. In some embodiments, the antigen-binding molecule is capable of inhibiting dimerization of HER3 and HER4. In some embodiments, the antigen-binding molecule is capable of inhibiting dimerization of HER3 and HGFR. In some embodiments, the antigen-binding molecule is capable of inhibiting dimerization of HER3 and IGF1R. In some embodiments, the antigen-binding molecule is capable of inhibiting dimerization of HER3 and cMet.

[0384] The ability of an antigen-binding molecule to inhibit the interaction between two factors can be determined, for example, by analyzing the interaction in the presence of an antibody / fragment, or after incubation with an antibody / fragment of one or both of the interaction partners. Assays to determine whether a given antigen-binding molecule is capable of inhibiting the interaction between two interaction partners include competitive ELISA assays and SPR analysis. In some embodiments, the antigen-binding molecule is a competitive inhibitor of the interaction between HER3 and its interaction partner.

[0385] In some embodiments, an antigen-binding molecule of the invention is capable of inhibiting the interaction of HER3 with an interaction partner of HER3 (e.g., HER3, HER2, EGFR, HER4, HGFR, IGF1R, and / or cMet) in a suitable assay to less than 1-fold, e.g., <0.99-fold, <0.95-fold, <0.9-fold, <0.85-fold, <0.8-fold, <0.75-fold, <0.7-fold, <0.65-fold, <0.6-fold, <0.55-fold, <0.5-fold, <0.45-fold, <0.4-fold, <0.35-fold, <0.3-fold, <0.25-fold, <0.2-fold, <0.15-fold, <0.1-fold, <0.05-fold, or <0.01-fold, the level of interaction of HER3 with the interaction partner of HER3 in the absence of the antigen-binding molecule (or in the presence of a suitable control antigen-binding molecule).

[0386] The ability of an antigen-binding molecule to inhibit the interaction between interaction partners can also be determined by analyzing downstream functional consequences of such interaction. For example, downstream functional consequences of the interaction between HER3 and its interaction partner include signal transduction by PI3K / AKT / mTOR and / or MAPK. For example, the ability of an antigen-binding molecule to inhibit the interaction between HER3 and its interaction partner can be determined by analyzing signal transduction by PI3K / AKT / mTOR and / or MAPK after treatment with NRG in the presence of the antigen-binding molecule. Signal transduction by PI3K / AKT / mTOR and / or MAPK can be detected and quantified, for example, using an antibody capable of detecting phosphorylated members of a signal transduction pathway.

[0387] The ability of an antigen-binding molecule to inhibit the interaction of HER3 with an interaction partner of HER3 can also be determined by analyzing the proliferation of cells expressing HER3 after treatment with NRG in the presence of the antigen-binding molecule. Cell proliferation can also be determined, for example, by detecting changes in cell number over time. 3It may be determined by in vitro analysis of H-thymidine incorporation, for example, by the CFSE dilution assay described in Fulcher and Wong, Immunol Cell Biol (1999), 77(6):559-564, which is incorporated herein by reference in its entirety.

[0388] In some embodiments, the antigen binding molecules of the invention are capable of inhibiting the proliferation of cells harboring a mutation to V600 of BRAF, e.g., cells containing a V600E or V600K mutation of BRAF (see Example 10).

[0389] In some embodiments, the antigen-binding molecule inhibits HER3-mediated signaling. HER3-mediated signaling can be analyzed, for example, using assays for correlates of HER3-mediated signaling, such as cell proliferation and / or phosphorylation of one or more signaling molecules in the PI3K / AKT / mTOR and / or MAPK signaling pathways.

[0390] In some embodiments, the antigen-binding molecules of the invention are capable of inhibiting PI3K / AKT / mTOR and / or MAPK signaling in HER3-expressing cells. The level of signaling by PI3K / AKT / mTOR and / or MAPK can be analyzed, for example, by detecting and quantifying the phosphorylation of one or more components of the PI3K / AKT / mTOR and / or MAPK pathways after stimulation with NRG (see Example 4.3).

[0391] In some embodiments, antigen-binding molecules of the invention are capable of inhibiting the proliferation of HER3-expressing cells, for example, in response to stimulation with NRG. In some embodiments, antigen-binding molecules of the invention are capable of inhibiting the proliferation of HER3-expressing cells in a suitable assay to less than 1-fold, e.g., ≦0.99-fold, ≦0.95-fold, ≦0.9-fold, ≦0.85-fold, ≦0.8-fold, ≦0.75-fold, ≦0.7-fold, ≦0.65-fold, ≦0.6-fold, ≦0.55-fold, ≦0.5-fold, ≦0.45-fold, ≦0.4-fold, ≦0.35-fold, ≦0.3-fold, ≦0.25-fold, ≦0.2-fold, ≦0.15-fold, ≦0.1-fold, ≦0.05-fold, or ≦0.01-fold the level of proliferation of HER3-expressing cells in the absence of the antigen-binding molecule (or in the presence of a suitable control antigen-binding molecule).

[0392] In some embodiments, antigen-binding molecules of the invention are capable of inhibiting PI3K / AKT / mTOR and / or MAPK signaling in HER3-expressing cells in a suitable assay to less than 1-fold, e.g., <0.99-fold, <0.95-fold, <0.9-fold, <0.85-fold, <0.8-fold, <0.75-fold, <0.7-fold, <0.65-fold, <0.6-fold, <0.55-fold, <0.5-fold, <0.45-fold, <0.4-fold, <0.35-fold, <0.3-fold, <0.25-fold, <0.2-fold, <0.15-fold, <0.1-fold, <0.05-fold, or <0.01-fold, the level of signaling by HER3-expressing cells in the absence of the antigen-binding molecule (or in the presence of a suitable control antigen-binding molecule).

[0393] HER3-mediated signaling may be examined in vitro, for example, as described in Example 8.9, or in vivo, for example, as described in Example 11.

[0394] ADCC activity may be analyzed, for example, according to the method described in Yamashita et al., Scientific Reports (2016), 6:19772 (incorporated herein by reference in its entirety), or by the method described, for example, in Jedema et al., Blood (2004), 103:2677-82 (incorporated herein by reference in its entirety). 51 ADCC activity may also be analyzed using the Pierce LDH Cytotoxicity Assay Kit (described in Example 5 herein) according to the manufacturer's instructions.

[0395] ADCPs can be analyzed, for example, according to the methods described in Kamen et al., J Immunol (2017), 198 (Suppl. 1) 157.17, which is incorporated herein by reference in its entirety.

[0396] The ability to induce CDC can be analyzed using, for example, a C1q binding assay, as described, for example, in Schlothauer et al., Protein Engineering, Design and Selection (2016), 29(10):457-466 (incorporated herein by reference in its entirety).

[0397] The thermal stability of an antigen-binding molecule can be analyzed by methods well known to those skilled in the art, including differential scanning fluorimetry and differential scanning calorimetry (DSC), for example, as described in He et al., J Pharm Sci. (2010), which is incorporated herein by reference in its entirety. Thermal stability can be reflected by the melting temperature (Tm), unfolding temperature, or decomposition temperature (e.g., expressed in °C or °F).

[0398] In some embodiments, an antigen-binding molecule comprising an Fc region described herein binds to an activating Fcγ receptor (e.g., hFcγRIIa (e.g., hFcγRIIa167H, hFcγRIIa167R), hFcγRIIIa (e.g., hFcγRIIIa158V, hFcγRIIIa158F), mFcγRIV, mFcγRIII) with a binding affinity that is greater than 1-fold, e.g., greater than 2, 3, 4, 5, 6, 7, 8, 9, 10, 15-fold, or greater than 20-fold greater than the binding affinity for an activating Fcγ receptor of an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175. In some embodiments, the K for binding to an activating Fcγ receptor of an antigen-binding molecule comprising an Fc region described herein is D is the K for an activating Fcγ receptor of an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequences of SEQ ID NOs: 174 to 175. D of the total amount of the α-tocopherol-containing compound, for example, less than 1 times, for example, less than 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06 times, or less than 0.05 times.

[0399] In some embodiments, an antigen-binding molecule comprising an Fc region described herein has a K of 1000 nM or less, preferably one of: <500 nM, <100 nM, <75 nM, <50 nM, <40 nM, <30 nM, <20 nM, <15 nM, <12.5 nM, <10 nM, <9 nM, <8 nM, <7 nM, <6 nM, <5 nM, <4 nM, <3 nM, <2 nM, or <1 nM. D and binds to activating Fcγ receptors (e.g., hFcγRIIa (e.g., hFcγRIIa167H, hFcγRIIa167R), hFcγRIIIa (e.g., hFcγRIIIa158V, hFcγRIIIa158F), mFcγRIV, mFcγRIII).

[0400] In some embodiments, an antigen-binding molecule comprising an Fc region described herein binds to FcRn (e.g., hFcRn, mFcRn) with a binding affinity that is greater than 1-fold, e.g., greater than 2, 3, 4, 5, 6, 7, 8, 9, 10, 15-fold, or greater than 20-fold, that of an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175. In some embodiments, the K for binding to FcRn of an antigen-binding molecule comprising an Fc region described herein is D is the K for FcRn of an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequences of SEQ ID NOs: 174 to 175. D of the total amount of the α-tocopherol-containing compound, for example, less than 1 times, for example, less than 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2, 0.1, 0.09, 0.08, 0.07, 0.06 times, or less than 0.05 times.

[0401] In some embodiments, an antigen-binding molecule comprising an Fc region described herein has a K of 1000 nM or less, preferably one of: <500 nM, <100 nM, <75 nM, <50 nM, <40 nM, <30 nM, <20 nM, <15 nM, <12.5 nM, <10 nM, <9 nM, <8 nM, <7 nM, <6 nM, <5 nM, <4 nM, <3 nM, <2 nM, or <1 nM. D and binds to FcRn (e.g., hFcRn, mFcRn).

[0402] In some embodiments, an antigen-binding molecule comprising an Fc region described herein binds to an inhibitory Fcγ receptor (e.g., hFcγRIIb, mFcγRIIb) with a binding affinity that is less than 1-fold, for example, less than 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2-fold, or less than 0.1-fold, of the binding affinity for an inhibitory Fcγ receptor of an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175. In some embodiments, the K for binding to an inhibitory Fcγ receptor of an antigen-binding molecule comprising an Fc region described herein isD teeth , K for inhibitory Fcγ receptors of equivalent antigen-binding molecules having an Fc region composed of CH2-CH3 having the amino acid sequences of SEQ ID NOs: 174 to 175 D of more than 1-fold, e.g., more than 2, 3, 4, 5, 6, 7, 8, 9-fold, or more than 10-fold.

[0403] In some embodiments, an antigen-binding molecule comprising an Fc region described herein binds to an inhibitory Fcγ receptor (e.g., hFcγRIIb, mFcγRIIb) with a K of 1 nM or more, preferably one of ≥ 5 nM, ≥ 10 nM, ≥ 50 nM, ≥ 100 nM, ≥ 500 nM, ≥ 1000 nM, ≥ 2000 nM, ≥ 3000 nM, ≥ 4000 nM, or ≥ 5000 nM. D Combine with.

[0404] In some embodiments, the binding selectivity of an antigen-binding molecule comprising an Fc region described herein to an activating Fcγ receptor (e.g., hFcγRIIa) relative to an inhibitory Fcγ receptor (e.g., hFcγRIIb) is more than 1-fold, e.g., more than 2-, 3-, 4-, 5-, 6-, 7-, 8-, 9-, 10-, 15-, or more than 20-fold, the binding selectivity conferred by an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175.

[0405] In some embodiments, antigen-binding molecules comprising an Fc region described herein confer greater than 1-fold, e.g., greater than 2, 3, 4, 5, 6, 7, 8, 9, 10, 15-fold, or greater than 20-fold ADCC than that conferred by an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175.

[0406] In some embodiments, in an assay for ADCC activity, the EC50 (ng / ml) determined for an antigen-binding molecule comprising an Fc region described herein is less than 1-fold, for example, less than 0.9, 0.8, 0.7, 0.6, 0.5, 0.4, 0.3, 0.2-fold, or less than 0.1-fold, the EC50 (ng / ml) determined for an equivalent antigen-binding molecule having an Fc region composed of CH2-CH3 having the amino acid sequence of SEQ ID NOs: 174-175.

[0407] In some embodiments, the EC50 (ng / ml) for an antigen-binding molecule comprising an Fc region described herein in an assay for ADCC activity is 500 ng / ml or less, preferably one of <400 ng / ml, <300 ng / ml, <200 ng / ml, <100 ng / ml, <90 ng / ml, <80 ng / ml, <70 ng / ml, <60 ng / ml, <50 ng / ml, <40 ng / ml, <30 ng / ml, <20 ng / ml, or <10 ng / ml.

[0408] In some embodiments, an antigen-binding molecule comprising an Fc region described herein has a melting temperature, unfolding temperature, or decomposition temperature that is ≥ 0.75 and ≤ 1.25 times, for example, ≥ 0.8 and ≤ 1.2 times, ≥ 0.85 and ≤ 1.15 times, ≥ 0.9 and ≤ 1.1 times, ≥ 0.9 ... The polymer may have a melting temperature, unfolding temperature, or decomposition temperature that is 0.91x and ≦1.09x, ≧0.92x and ≦1.08x, ≧0.93x and ≦1.07x, ≧0.94x and ≦1.06x, ≧0.95x and ≦1.05x, ≧0.96x and ≦1.04x, ≧0.97x and ≦1.03x, ≧0.98x and ≦1.02x, or ≧0.99x and ≦1.01x.

[0409] In some embodiments, the antigen-binding molecules of the present invention are capable of enhancing the killing of HER3-expressing cells. The killing of HER3-expressing cells is enhanced by enhancing the effector function of the antigen-binding molecule. In embodiments in which the antigen-binding molecule comprises an Fc region, the antigen-binding molecule may increase killing of HER3-expressing cells via one or more of complement-dependent cytotoxicity (CDC), antibody-dependent cell-mediated cytotoxicity (ADCC), and antibody-dependent cellular phagocytosis (ADCP).

[0410] Antigen-binding molecules capable of increasing the killing of HER3-expressing cells can be identified by observing an increased level of killing of HER3-expressing cells in the presence of the antigen-binding molecule (or after incubation of HER3-expressing cells with the antigen-binding molecule) compared to the level of cell killing detected in the absence of the antigen-binding molecule (or in the presence of a suitable control antigen-binding molecule) in an appropriate assay. Assays for CDC, ADCC, and ADCP are well known to those skilled in the art. The level of killing of HER3-expressing cells can also be determined by measuring the number / proportion of surviving and / or non-surviving HER3-expressing cells after exposure to different treatment conditions.

[0411] In some embodiments, antigen-binding molecules of the invention are capable of increasing killing of HER3-expressing cells (e.g., HER3-expressing cancer cells) by more than 1-fold, for example, ≧1.01-fold, ≧1.02-fold, ≧1.03-fold, ≧1.04-fold, ≧1.05-fold, ≧1.1-fold, ≧1.2-fold, ≧1.3-fold, ≧1.4-fold, ≧1.5-fold, ≧1.6-fold, ≧1.7-fold, ≧1.8-fold, ≧1.9-fold, ≧2-fold, ≧3-fold, ≧4-fold, ≧5-fold, ≧6-fold, ≧7-fold, ≧8-fold, ≧9-fold, or ≧10-fold the level of killing observed in the absence of the antigen-binding molecule (or in the presence of a suitable control antigen-binding molecule).

[0412] In some embodiments, the antigen-binding molecules of the invention are capable of reducing the number of HER3-expressing cells (e.g., HER3-expressing cancer cells) in an equivalent assay to less than 1-fold, e.g., <0.99-fold, <0.95-fold, <0.9-fold, <0.85-fold, <0.8-fold, <0.75-fold, <0.7-fold, <0.65-fold, <0.6-fold, <0.55-fold, <0.5-fold, <0.45-fold, <0.4-fold, <0.35-fold, <0.3-fold, <0.25-fold, <0.2-fold, <0.15-fold, <0.1-fold, <0.05-fold, or <0.01-fold, the number of HER3-expressing cells (e.g., HER3-expressing cancer cells) detected after incubation in the absence of the antigen-binding molecule (or after incubation in the presence of a suitable control antigen-binding molecule).

[0413] In some embodiments, the antigen-binding molecules of the invention inhibit the onset and / or progression of cancer in vivo.

[0414] In some embodiments, the antigen-binding molecule causes increased killing of cancer cells, e.g., by effector immune cells. In some embodiments, the antigen-binding molecule causes a reduction in the number of cancer cells in vivo, e.g., compared to appropriate control conditions. In some embodiments, the antigen-binding molecule inhibits tumor growth, e.g., as determined by measuring tumor size / volume over time.

[0415] The antigen-binding molecules of the present invention can be analyzed for their ability to inhibit the onset and / or progression of cancer in a suitable in vivo model, such as a cell line-derived xenograft model. The cell line-derived xenograft model can be derived from HER3-expressing cancer cells. In some embodiments, the model is an N87 cell-derived model, an SNU16 cell-derived model, an FaDu cell-derived model, an OvCAR8 cell-derived model, an HCC95 cell-derived model, an A549 cell-derived model, an ACHN cell-derived model, or an HT29 cell-derived model.

[0416] The cancer may be a HER3-associated cancer (i.e., a cancer in which expression of the HER3 gene / protein is a risk factor and / or contributes to the onset, development, progression, or progression of cancer), as described herein. The cancer may be a cancer that is positively associated with symptom severity and / or metastasis. The cancer may comprise HER3-expressing cells. In some embodiments, the cancer comprises a HER3+ tumor.

[0417] In some embodiments, administration of an antigen-binding molecule according to the invention may result in one or more of: inhibiting cancer onset / progression; delaying cancer onset / preventing cancer onset; reducing tumor growth / delaying tumor growth / preventing tumor growth; reducing metastasis / delaying metastasis / preventing metastasis; reducing the severity of cancer symptoms; reducing cancer cell number; reducing tumor size / volume; and / or increasing survival (e.g., progression-free survival) as determined, for example, in a suitable HER3-expressing cancer cell line-derived xenograft model.

[0418] In some embodiments, antigen-binding molecules of the invention are capable of inhibiting tumor growth in a xenograft model derived from a HER3-expressing cancer cell line to less than 1-fold, e.g., <0.99-fold, <0.95-fold, <0.9-fold, <0.85-fold, <0.8-fold, <0.75-fold, <0.7-fold, <0.65-fold, <0.6-fold, <0.55-fold, <0.5-fold, <0.45-fold, <0.4-fold, <0.35-fold, <0.3-fold, <0.25-fold, <0.2-fold, <0.15-fold, <0.1-fold, <0.05-fold, or <0.01-fold, of tumor growth observed in the absence of treatment with the antigen-binding molecule (or after treatment with an appropriate negative control antigen-binding molecule). Chimeric antigen receptor (CAR) The present invention also provides a chimeric antigen receptor (CAR) comprising an antigen-binding molecule or polypeptide of the present invention.

[0419] CAR is a recombinant receptor that provides both antigen binding and T cell activation function.The structure and operation of CAR are reviewed in, for example, Dotti et al., Immunol Rev (2014), 257(1), which is incorporated herein by reference in its entirety.CAR comprises an antigen binding region that is connected to a cell membrane anchor region and a signal transduction region.Optionally, hinge region can separate the antigen binding region from the cell membrane anchor region, and can act as a flexible linker.

[0420] The CAR of the present invention comprises an antigen-binding region that comprises or consists of an antigen-binding molecule of the present invention, or that comprises or consists of a polypeptide according to the present invention.

[0421] The cell membrane anchor region is provided between the antigen-binding region and the signaling region of the CAR, and allows for anchoring of the CAR, with the antigen-binding region in the extracellular space and the signaling region inside the cell, to the cell membrane of the cell expressing the CAR. In some embodiments, the CAR comprises a cell membrane anchor region that comprises, consists of, or is derived from the amino acid sequence of the transmembrane region of one of CD3-zeta, CD4, CD8, or CD28. As used herein, a region "derived from" a reference amino acid sequence includes an amino acid sequence that has at least 60%, e.g., at least 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to the reference sequence.

[0422] The signaling region of a CAR enables T cell activation. The signaling region of a CAR may include an amino acid sequence from the intracellular domain of CD3-zeta, which provides an immunoreceptor tyrosine-based activation motif (ITAM) for phosphorylation and activation of CAR-expressing T cells. CARs have also utilized signaling regions containing sequences from other ITAM-containing proteins, such as FcγRI (Haynes et al., 2001, J Immunol, 166(1):182-187). The signaling region of a CAR may also include a costimulatory sequence derived from the signaling region of a costimulatory molecule to facilitate activation of CAR-expressing T cells upon binding to a target protein. Suitable costimulatory molecules include CD28, OX40, and OX40. , 4-1BB, ICOS, and CD27. In some cases, the CAR is engineered to provide costimulation of different intracellular signaling pathways. For example, signaling associated with CD28 costimulation preferentially activates the phosphatidylinositol 3-kinase (P13K) pathway, while 4-1BB-mediated signaling is mediated through the TNF receptor-associated factor (TRAF) adaptor protein. Thus, the signaling region of the CAR may contain costimulatory sequences derived from the signaling regions of more than one costimulatory molecule. In some embodiments, the CAR of the present invention comprises one or more costimulatory sequences that comprise, consist of, or are derived from the amino acid sequence of one or more intracellular domains of CD28, OX40, 4-1BB, ICOS, and CD27.

[0423] The optional hinge region can separate the antigen-binding domain from the transmembrane domain and can act as a flexible linker. The hinge region can be derived from IgG1. In some embodiments, the CAR of the present invention comprises a hinge region that comprises, consists of, or is derived from the amino acid sequence of the hinge region of this IgG1.

[0424] Also provided are cells comprising a CAR according to the present invention. A CAR according to the present invention can be used to generate CAR-expressing immune cells, such as CAR-T cells or CAR-NK cells. Engineering a CAR into immune cells can be performed during in vitro culture.

[0425] The antigen-binding region of the CAR of the present invention can be provided in any suitable format, e.g., scFv, scFab, etc. Nucleic acids and vectors The invention provides a nucleic acid or nucleic acids encoding an antigen-binding molecule, polypeptide, or CAR in accordance with the invention.

[0426] In some embodiments, the nucleic acid may be purified or isolated, for example, from other nucleic acids, or from naturally occurring biological material, hi some embodiments, the nucleic acid(s) comprise or consist of DNA and / or RNA.

[0427] The present invention also provides a vector or vectors comprising a nucleic acid or nucleic acids in accordance with the invention.

[0428] The nucleotide sequence may be contained within a vector, for example, an expression vector. As used herein, a "vector" is a nucleic acid molecule used as a vehicle to introduce exogenous nucleic acid into a cell. The vector may be a vector for expressing a nucleic acid in a cell. Such a vector may include a promoter sequence operably linked to the nucleotide sequence encoding the sequence to be expressed. The vector may also include a stop codon and an expression enhancer. Any suitable vector, promoter, enhancer, and stop codon known in the art may be used to express a peptide or polypeptide from a vector according to the present invention.

[0429] The term "operably linked" can include the situation where a selected nucleic acid sequence and a regulatory nucleic acid sequence (e.g., a promoter and / or enhancer) are covalently linked such that expression of the nucleic acid sequence is under the influence or control of the regulatory sequence (thereby forming an expression cassette). Thus, a regulatory sequence is operably linked to a selected nucleic acid sequence if it is capable of effecting transcription of the nucleic acid sequence. The resulting transcript(s) then produce the desired peptide(s) / polypeptide(s). It can be translated as (number).

[0430] Suitable vectors include plasmids, binary vectors, DNA vectors, mRNA vectors, viral vectors (e.g., gammaretroviral vectors (e.g., murine leukemia virus (MLV)-derived vectors), lentiviral vectors, adenoviral vectors, adeno-associated viral vectors, vaccinia viral vectors, and herpes viral vectors), transposon-based vectors, and artificial chromosomes (e.g., yeast artificial chromosomes).

[0431] In some embodiments, the vector can be a eukaryotic vector, e.g., a vector containing elements necessary for expression of a protein from a vector in a eukaryotic cell, hi some embodiments, the vector can be a mammalian vector, e.g., containing a cytomegalovirus (CMV) or SV40 promoter driving expression of a protein.

[0432] The component polypeptides of the antigen-binding molecules of the present invention may be encoded by different nucleic acids from a plurality of nucleic acids or by different vectors from a plurality of vectors. The present invention also provides cells comprising or expressing an antigen-binding molecule, polypeptide, or CAR according to the invention. Also provided are cells comprising or expressing a nucleic acid, multiple nucleic acids, single vector, or multiple vectors according to the invention.

[0433] The cell can be a eukaryotic cell, e.g., a mammalian cell. The mammal can be a primate (rhesus monkey, cynomolgus monkey, non-human primate, or human), or a non-human mammal (e.g., rabbit, guinea pig, rat, mouse or other rodent (including any animal in the order Murine), cat, dog, pig, sheep, goat, cattle (including bovine, e.g., dairy cow, or any animal in the order Bovidae), horse (including any animal in the order Equine), donkey, and non-human primate).

[0434] The present invention also provides methods for producing a cell comprising a nucleic acid(s) or vector(s) in accordance with the invention, the method comprising introducing into a cell a nucleic acid, multiple nucleic acids, a vector, or multiple vectors in accordance with the invention. In some embodiments, introducing into a cell the isolated nucleic acid(s) or isolated vector(s) in accordance with the invention comprises transformation, transfection, electroporation, or transduction (e.g., retroviral transduction).

[0435] The present invention also provides methods for producing cells that express / comprise an antigen-binding molecule, polypeptide, or CAR according to the present invention, comprising introducing into the cell a nucleic acid, multiple nucleic acids, single vector, or multiple vectors according to the present invention. In some embodiments, the method further comprises culturing the cell under conditions suitable for expression of the nucleic acid(s) or vector(s) by the cell. In some embodiments, the method is performed in vitro.

[0436] The present invention also provides cells obtained or obtainable by a method according to the invention. Production of antigen-binding molecules and polypeptides The antigen-binding molecules and polypeptides according to the present invention can be prepared according to methods for producing polypeptides known to those skilled in the art.

[0437] Polypeptides can be prepared by chemical synthesis, for example, liquid phase or solid phase synthesis. The peptides / polypeptides may be synthesized, for example, using the methods described in Chandrudu et al., Molecules (2013), 18:4373-4388, which is incorporated herein by reference in its entirety.

[0438] Alternatively, antigen-binding molecules and polypeptides can be produced by recombinant expression. Molecular biology methods suitable for the recombinant production of polypeptides are well known in the art, such as those disclosed in Green and Sambrook, "Molecular Cloning: A Laboratory Manual" (4th ed.), Cold Spring Harbor Press, 2012; and Nat Methods. (2008), 5(2):135-146, all of which are incorporated herein by reference in their entirety. Methods for the recombinant production of antigen-binding molecules are also described in Frenzel et al., Front Immunol. (2013), 4:217; and Kunert and Reinhart, Appl Microbiol Biotechnol. (2016), 100:3451-3461, all of which are incorporated herein by reference in their entirety.

[0439] In some cases, an antigen-binding molecule of the present invention is composed of more than one polypeptide chain. In such cases, production of the antigen-binding molecule may involve transcription and translation of more than one polypeptide and subsequent assembly of the polypeptide chains to form the antigen-binding molecule.

[0440] For recombinant production according to the present invention, any cell suitable for expressing a polypeptide can be used. The cell can be a prokaryotic or eukaryotic cell. In some embodiments, the cell is a prokaryotic cell, such as an archaeal or bacterial cell. In some embodiments, the bacterium can be a gram-negative bacterium, such as a bacterium of the Enterobacteraceae family, e.g., Escherichia coli. In some embodiments, the cell is a eukaryotic cell, such as a yeast cell, a plant cell, an insect cell, or a mammalian cell, e.g., a CHO, HEK (e.g., HEK293), HeLa, or COS cell. In some embodiments, the cell is a CHO cell that transiently or stably expresses a polypeptide.

[0441] In some cases, the cells are not prokaryotic because some prokaryotic cells do not allow the same folding or post-translational modifications as eukaryotic cells. In addition, extremely high expression levels are possible in eukaryotic cells, and proteins are easy to purify from eukaryotic cells using appropriate tags. Specific plasmids that enhance protein secretion into the medium can also be used.

[0442] In some embodiments, polypeptides may be prepared by cell-free protein synthesis (CFPS), for example, using the system described in Zemella et al., Chembiochem (2015), 16(17):2420-2431, which is incorporated herein by reference in its entirety.

[0443] Production may involve the culture or fermentation of eukaryotic cells that have been modified to express the polypeptide(s) of interest. Cultivation or fermentation may be carried out in a bioreactor with an appropriate supply of nutrients, air / oxygen, and / or growth factors. Secreted proteins may be recovered by fractionating the culture medium / fermentation broth from the cells, extracting the protein content, separating the individual proteins, and isolating the secreted polypeptide(s). Cultivation, fermentation, and isolation methods are well known to those of skill in the art and are described, for example, in Green and Sambrook, "Molecular Cloning: A Laboratory Manual" (4th ed.; incorporated herein by reference).

[0444] A bioreactor contains one or more reaction vessels in which cells can be cultured. Cultivation in a bioreactor can occur continuously, with a continuous inflow of reactants into the reactor and a continuous outflow of cultured cells from the reactor. Alternatively, cultivation can occur in batches. Bioreactors monitor and control environmental conditions, such as pH, oxygen, flow rates into and out of the reactor, and agitation within the reactor, to provide optimal conditions for the cultured cells.

[0445] After culturing cells expressing the antigen-binding molecule / polypeptide(s), the polypeptide(s) of interest can be isolated. Any suitable method known in the art for separating proteins from cells can be used. To isolate the polypeptide, it may be necessary to separate the cells from the nutrient medium. If the polypeptide(s) of interest are secreted from the cells, the cells can be separated from the culture medium containing the secreted polypeptide(s) of interest by centrifugation. If the polypeptide(s) of interest are collected intracellularly, protein isolation can include centrifugation to separate the cells from the cell culture medium, treatment of the cell pellet with a lysis buffer, and disruption of the cells by sonication, rapid freeze-thawing, or osmotic lysis.

[0446] It may then be desirable to isolate the polypeptide(s) of interest from the supernatant or culture medium, which may contain other proteins and non-protein components. A common technique for separating protein components from the supernatant or culture medium is precipitation. Proteins with different solubility are precipitated with different concentrations of precipitants, such as ammonium sulfate. For example, low concentrations of precipitant extract water-soluble proteins. Therefore, by adding increasing concentrations of precipitant, proteins with different solubility can be distinguished. Dialysis can then be used to remove ammonium sulfate from the separated proteins.

[0447] Other methods for distinguishing between different proteins are known in the art, such as ion exchange chromatography and size chromatography, which may be used as alternatives to precipitation or may be performed subsequent to precipitation.

[0448] Once the polypeptide(s) of interest have been isolated from the culture, it may be desirable or necessary to concentrate the polypeptide(s). Numerous methods for concentrating proteins are known in the art, such as ultrafiltration or lyophilization. composition The present invention also provides compositions comprising the antigen-binding molecules, polypeptides, CARs, nucleic acids, expression vectors, and cells described herein.

[0449] The antigen-binding molecules, polypeptides, CARs, nucleic acids, expression vectors, and cells described herein may be formulated as pharmaceutical compositions or medicaments for clinical use and may include pharmaceutically acceptable carriers, diluents, excipients, or adjuvants. The compositions may be formulated for local, parenteral, systemic, intracavitary, intravenous, intraarterial, intramuscular, intrathecal, intraocular, intraconjunctival, intratumoral, subcutaneous, intradermal, intrathecal, oral, or transdermal administration routes, which may include injection or infusion.

[0450] Suitable formulations may include antigen-binding molecules in a sterile or isotonic medium. Medicaments and pharmaceutical compositions may be formulated in a fluid, including in gel form. Fluid formulations may be formulated for administration by injection or infusion (e.g., via a catheter) to a selected area within the human or animal body.

[0451] In some embodiments, the composition is administered for injection or infusion, e.g., into a blood vessel or tumor. It is formulated into

[0452] Also provided in accordance with the present invention are methods for making the pharmaceutically useful compositions described herein, which may include one or more steps selected from: making an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), or cell(s) described herein; isolating an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), or cell(s) described herein; and / or mixing an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), or cell(s) described herein with a pharmaceutically acceptable carrier, adjuvant, excipient, or diluent.

[0453] For example, a further aspect of the invention described herein relates to a method of formulating or making a medicament or pharmaceutical composition for use in treating a disease / condition (e.g., cancer), comprising the step of formulating the pharmaceutical composition or medicament by mixing an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), or cell(s) described herein with a pharmaceutically acceptable carrier, adjuvant, excipient, or diluent. Therapeutic and prophylactic applications The antigen-binding molecules, polypeptides, CARs, nucleic acids, expression vectors, cells, and compositions described herein are used in therapeutic and prophylactic methods.

[0454] The present invention provides an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), cell, or composition described herein for use in a method of medical treatment or prevention. Also provided is the use of an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), cell, or composition described herein in the manufacture of a medicament for treating or preventing a disease or condition. Also provided is a method of treating or preventing a disease or condition, comprising administering to a subject a therapeutically or prophylactically effective amount of an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), cell, or composition described herein.

[0455] The method may be effective in reducing the onset or progression of the disease / condition, alleviating the symptoms of the disease / condition, or reducing the pathology of the disease / condition. The method may be effective in preventing the progression of the disease / condition, e.g., preventing the worsening of the disease / condition or slowing the rate of onset of the disease / condition. In some embodiments, the method may result in an improvement of the disease / condition, e.g., a reduction in the symptoms of the disease / condition, or a reduction in some other correlate of the severity / activity of the disease / condition. In some embodiments, the method may prevent the onset of a later stage of the disease / condition (e.g., chronic or metastatic).

[0456] It will be understood that the articles of the present invention can be used for the treatment / prevention of any disease / condition that derives therapeutic or prophylactic benefit from a reduction in the number and / or activity of cells expressing HER3. For example, the disease / condition can be one in which cells expressing HER3 are pathologically involved, such as one in which an increase in the number / proportion of cells expressing HER3 is positively associated with the occurrence, development, or progression of the disease / condition and / or the severity of one or more symptoms of the disease / condition, or one in which an increase in the number / proportion of cells expressing HER3 is a risk factor for the occurrence, development, or progression of the disease / condition.

[0457] In some embodiments, the disease / condition treated / prevented in accordance with the present invention is a disease / condition characterized by an increase in the number / proportion / activity of cells expressing HER3, e.g., compared to the number / proportion / activity of cells expressing HER3 in the absence of the disease / condition.

[0458] In some embodiments, the disease / condition to be treated / prevented is cancer.

[0459] Cancer can be any unwanted cell proliferation (or any disease manifested by unwanted cell proliferation), neoplasm, or tumor. Cancer can be benign or malignant, primary, or secondary (metastatic). A neoplasm or tumor can be any abnormal growth or proliferation of cells and can be located in any tissue. The cancer can be, for example, a cancer of tissue / cells derived from the adrenal gland, adrenal medulla, anus, appendix, bladder, blood, bone, bone marrow, brain, breast, cecum, central nervous system (including or excluding the brain), cerebellum, cervix, colon, duodenum, endometrium, epithelial cells (e.g., renal epithelium), gallbladder, esophagus, glial cells, heart, ileum, jejunum, kidney, lacrimal gland, larynx, liver, lung, lymph, lymph node, lymphoblast, jaw, mediastinum, mesentery, myometrium, nasopharynx, omentum, oral cavity, ovary, pancreas, parotid gland, peripheral nervous system, peritoneum, pleura, prostate, salivary gland, sigmoid colon, skin, small intestine, soft tissue, spleen, stomach, testis, thymus, thyroid, tongue, tonsils, trachea, uterus, vulva, and / or leukocytes.

[0460] The tumors to be treated may be nervous system tumors or non-nervous system tumors. Nervous system tumors, such as glioma, medulloblastoma, meningioma, neurofibroma, ependymoma, schwannoma, neurofibrosarcoma, astrocytoma, and oligodendroglioma, may originate from the central nervous system or the peripheral nervous system. Non-nervous system cancers / tumors may originate from any other non-nervous tissue, including melanoma, mesothelioma, lymphoma, myeloma, leukemia, non-Hodgkin's lymphoma (NHL), Hodgkin's lymphoma, chronic myeloid leukemia (CML), acute myeloid leukemia (AML), myelodysplastic syndrome (MDS), cutaneous T-cell lymphoma (CTCL), chronic lymphocytic leukemia (CLL), liver cancer, epidermoid carcinoma, prostate cancer, breast cancer, lung cancer, colon cancer, ovarian cancer, pancreatic cancer, thymic cancer, NSCLC, blood cancer, and sarcoma.

[0461] HER3 and its association with and role in cancer are reviewed in, for example, Karachaliou et al., BioDrugs. (2017), 31(1):63-73; and Zhang et al., Acta Biochimica et Biophysica Sinica (2016), 48(1):39-48, both of which are incorporated by reference in their entireties.

[0462] In some embodiments, the cancer is selected from cancer comprising cells that express HER3, solid tumors, breast cancer, breast cancer, ductal carcinoma, gastric cancer, gastric adenocarcinoma, colorectal cancer, colorectal adenocarcinoma, head and neck cancer, squamous cell carcinoma of the head and neck (SCCHN), lung cancer, lung adenocarcinoma, squamous cell lung carcinoma, ovarian cancer, ovarian carcinoma, serous ovarian adenocarcinoma, renal cancer, renal cell carcinoma, clear cell renal carcinoma, renal cell adenocarcinoma, papillary renal cell carcinoma, pancreatic cancer, pancreatic adenocarcinoma, pancreatic ductal adenocarcinoma, cervical cancer, cervical squamous cell carcinoma, skin cancer, melanoma, esophageal cancer, esophageal adenocarcinoma, liver cancer, hepatocellular carcinoma, cholangiocarcinoma, uterine cancer, endometrial carcinoma, thyroid cancer, thyroid carcinoma, pheochromocytoma, paraganglioma, bladder cancer, bladder urothelial carcinoma, prostate cancer, prostate adenocarcinoma, sarcoma, and thymoma.

[0463] In some embodiments, the cancer treated in accordance with the present invention is selected from a HER3-expressing cancer, gastric cancer (e.g., gastric carcinoma, gastric adenocarcinoma, gastrointestinal adenocarcinoma), head and neck cancer (e.g., head and neck squamous cell carcinoma), breast cancer, ovarian cancer (e.g., ovarian carcinoma), lung cancer (e.g., NSCLC, lung adenocarcinoma, squamous cell lung carcinoma), melanoma, prostate cancer, oral cancer (e.g., oropharyngeal cancer), kidney cancer (e.g., renal cell carcinoma), or colorectal cancer (e.g., colorectal carcinoma), esophageal cancer, pancreatic cancer, solid tumors, and / or liquid tumors.

[0464] Treatment / prevention may aim at one or more of delaying / preventing the onset / progression of cancer symptoms, reducing the severity of cancer symptoms, reducing cancer cell survival / growth / invasion / metastasis, reducing the number of cancer cells, and / or prolonging the survival of the subject.

[0465] In some embodiments, the cancer to be treated / prevented comprises cells that express an EGFR family member (e.g., HER3, EGFR, HER2, or HER4) and / or cells that express a ligand for an EGFR family member. In some embodiments, the cancer to be treated / prevented is a cancer that is positive for an EGFR family member. In some embodiments, the cancer overexpresses an EGFR family member and / or a ligand for an EGFR family member. Overexpression may be determined by detecting a level of expression that exceeds the level of expression by comparable non-cancerous cells / non-tumor tissue.

[0466] Expression can be determined by any suitable means. Expression can be gene expression or protein expression. Gene expression can be determined by detecting the mRNA encoding HER3, for example, through quantitative real-time PCR (qRT-PCR). For example, protein expression can be determined by antibody-based methods, for example, Western blot, immunohistochemistry, immunocytochemistry, flow cytometry, or ELISA.

[0467] In some embodiments, the cancer to be treated / prevented comprises cells that express HER3. In some embodiments, the cancer to be treated / prevented is a cancer that is positive for HER3. In some embodiments, the cancer overexpresses HER3. Overexpression of HER3 can be determined by detecting a level of expression of HER3 that exceeds the level of expression by comparable non-cancerous cells / non-tumor tissue.

[0468] In some embodiments, patients may be selected for the treatments described herein based on, for example, detection of a HER3-expressing or HER3-overexpressing cancer in a sample obtained from the subject.

[0469] In some embodiments, the cancer to be treated / prevented comprises cells that express a ligand for HER3 (e.g., NRG1 and / or NRG2). In some embodiments, the cancer to be treated / prevented comprises cells that express an expression level of NRG1 and / or NRG2 that exceeds the level of expression by comparable non-cancerous cells / non-tumor tissues.

[0470] Administration of the articles of the present invention is preferably in a "therapeutically effective" or "prophylactically effective" amount, that is, an amount sufficient to show a therapeutic or prophylactic benefit to the subject. The actual amount administered, and the rate and time-course of administration, will depend on the nature and severity of the disease / condition and the particular article being administered. Prescribing treatment, such as determining dosage, is within the responsibility of general practitioners and other medical professionals and typically takes into account the disease / disorder being treated, the condition of the individual subject, the site of delivery, the method of administration, and other factors known to practitioners. Examples of the techniques and protocols mentioned above can be found in "Remington's Pharmaceutical Sciences," 20th Edition, 2000, published by Lippincott, Williams & Wilkins.

[0471] Administration may be by itself or in combination with other treatments, either simultaneously or sequentially, depending on the condition being treated. The antigen-binding molecules or compositions described herein and therapeutic agents may be administered simultaneously or sequentially. be.

[0472] In some embodiments, the method includes further therapeutic or prophylactic intervention, for example, for the treatment / prevention of cancer. In some embodiments, the therapeutic or prophylactic intervention is selected from chemotherapy, immunotherapy, radiation therapy, surgery, vaccination, and / or hormonal therapy. In some embodiments, the therapeutic or prophylactic intervention includes leukapheresis. In some embodiments, the therapeutic or prophylactic intervention includes stem cell transplantation.

[0473] In some embodiments, the antigen binding molecule is administered in combination with an agent capable of inhibiting signaling mediated by an EGFR family member.

[0474] Accordingly, the present invention provides compositions comprising an article according to the invention (e.g., an antigen-binding molecule according to the invention) and another agent capable of inhibiting signaling mediated by an EGFR family member (e.g., EGFR, HER2, HER3, or HER4). Also provided is the use of such compositions in methods for the medical treatment and prevention of the diseases / conditions described herein.

[0475] Also provided are methods for treating / preventing the diseases / conditions described herein, comprising administering an article according to the invention (e.g., an antigen-binding molecule according to the invention) and another agent capable of inhibiting signaling mediated by an EGFR family member.

[0476] Agents capable of inhibiting signal transduction mediated by EGFR family members are known in the art and include, for example, small molecule inhibitors (e.g., tyrosine kinase inhibitors), monoclonal antibodies (and antigen-binding fragments thereof), peptide / polypeptide inhibitors (e.g., decoy ligands / receptors or peptide aptamers), and nucleic acids (e.g., antisense nucleic acids, splice-switching nucleic acids, or nucleic acid aptamers). Inhibitors of signal transduction mediated by EGFR family members include agents that inhibit signal transduction through a direct effect on an interacting partner that is an EGFR family member, and thus also inhibit downstream factors involved in signal transduction mediated by EGFR family members.

[0477] In some embodiments, the antagonist of signal transduction mediated by EGFR family members inhibits signal transduction mediated by one or more of EGFR, HER2, HER4, and HER3. Inhibitors of signal transduction mediated by EGFR family members are described, for example, in Yamaoka et al., Int. J. Mol. Sci. (2018), 19, 3491, which is incorporated herein by reference in its entirety. In some embodiments, the antagonist is a pan-ErbB inhibitor. In some embodiments, the antagonist is an inhibitor of signal transduction mediated by EGFR (e.g., cetuximab, panitumumab, gefitinib, erlotinib, lapatinib, afatinib, brigatinib, icotinib, osimertinib, zalutumumab, vandetanib, neciturumumab, nimotuzumab, dacomitinib, durigotuzumab, or matuzumab). In some embodiments, the antagonist is an inhibitor of HER2-mediated signaling (e.g., trastuzumab, pertuzumab, lapatinib, neratinib, afatinib, dacomitinib, MM-111, MCLA-128, or margetuximab). In some embodiments, the antagonist is an inhibitor of HER3-mediated signaling (e.g., seribantumab, lumletuzumab, elgemtumab, KTN3379, AV-203, GSK2849330, REGN1400, MP-RM-1, EV20, durigotuzumab, MM-111, istrastuzumab, MCLA-128, patritumab, EZN-3920, RB200, or U3-1402). In some embodiments, the antagonist is an inhibitor of HER4-mediated signaling (e.g., lapatinib, ibrutinib, afatinib, dacomitinib, or neratinib).

[0478] In some embodiments, the antagonist of EGFR family member-mediated signaling inhibits downstream effectors of EGFR family member-mediated signaling. Downstream effectors of EGFR family member-mediated signaling include, for example, PI3K, AKT, KRAS, BRAF, MEK / ERK, and mTOR. In some embodiments, the antagonist of EGFR family member-mediated signaling is an inhibitor of the MAPK / ERK pathway. In some embodiments, the antagonist of EGFR family member-mediated signaling is an inhibitor of the PI3K / ATK / mTOR pathway. In some embodiments, the antagonist is a PI3K inhibitor (e.g., pictilisib, bupalisib, idelalisib, copanlisib, or duvelisib). In some embodiments, the antagonist is an AKT inhibitor (e.g., MK-2206, AZD5363, ipatasertib, VQD-002, perifosine, or miltefosine). In some embodiments, the antagonist is a BRAF inhibitor (e.g., vemurafenib, dabrafenib, SB590885, XL281, RAF265, encorafenib, GDC-0879, PLX-4720, sorafenib, or LGX818). In some embodiments, the antagonist is a MEK / ERK inhibitor (e.g., trametinib, cobimetinib, binimetinib, selumetinib, PD-325901, CI-1040, PD035901, or TAK-733). In some embodiments, the antagonist is an mTOR inhibitor (e.g., rapamycin, deforolimus, temsirolimus, everolimus, ridaforolimus, or sapanisertib).

[0479] In some embodiments, the cancer treated according to aspects of the invention (including monotherapy or combination therapy) is a cancer that is resistant to treatment with an antagonist of signaling mediated by an EGFR family member (e.g., EGFR, HER2, HER4, and / or HER3), such as an antagonist described in the preceding three paragraphs. In some embodiments, the subject being treated has a cancer that is resistant to treatment with an antagonist of signaling mediated by an EGFR family member. In some embodiments, the subject being treated has a cancer that has developed resistance to treatment with an antagonist of signaling mediated by an EGFR family member. In some embodiments, the subject being treated has a cancer that previously responded to treatment with an antagonist of signaling mediated by an EGFR family member but is now resistant to treatment with the antagonist. In some embodiments, the subject being treated has a cancer that has recurred and / or progressed after treatment with an antagonist of signaling mediated by an EGFR family member. In some embodiments, the subject being treated has a cancer that initially responded to treatment with an antagonist of signaling mediated by an EGFR family member, but that subsequently progressed due to said treatment.

[0480] Those skilled in the art can readily identify cancers and subjects according to the preceding paragraphs. Such cancers and subjects can be identified, for example, by monitoring the onset / progression of cancer (and / or its correlates) over time, for example, during the course of treatment with an antagonist of EGFR family member-mediated signaling. In some embodiments, identifying such subjects / cancers can include, for example, in vitro analysis of a sample (e.g., biopsy). In some embodiments, the cancer can be determined to include cells with a mutation associated with reduced sensitivity and / or resistance to treatment with the antagonist. In some embodiments, the cancer can be determined to include cells with upregulated expression of an EGFR family member.

[0481] In certain embodiments, the cancer being treated is a cancer that is resistant to treatment with an antagonist of EGFR and / or HER2-mediated signaling. In some embodiments, the subject being treated has a cancer that is resistant to treatment with an antagonist of EGFR and / or HER2-mediated signaling. In some embodiments, the subject being treated has a cancer that has developed resistance to treatment with an antagonist of EGFR and / or HER2-mediated signaling. In some embodiments, the subject being treated has a cancer that previously responded to treatment with an antagonist of EGFR and / or HER2-mediated signaling but is now resistant to treatment with the antagonist. In some embodiments, the subject being treated has a cancer that has recurred and / or progressed after treatment with an antagonist of EGFR and / or HER2-mediated signaling. In some embodiments, the subject being treated has a cancer that initially responded to treatment with an antagonist of EGFR and / or HER2-mediated signaling but subsequently progressed due to said treatment.

[0482] In certain embodiments, the cancer to be treated comprises the mutation that confers resistance to the treatment with BRAF inhibitor.In some embodiments, the mutation is the mutation in BRAF V600.In some embodiments, the mutation is BRAF V600E or V600K.

[0483] In certain embodiments, the cancer being treated comprises a mutation that confers resistance to treatment with an inhibitor of BRAF (e.g., a mutation in V600 of BRAF), and the treatment comprises administration of vemurafenib or darafenib.

[0484] In some embodiments, the antigen-binding molecule is administered in combination with an agent capable of inhibiting signal transduction mediated by an immune checkpoint molecule. In some embodiments, the immune checkpoint molecule is, for example, PD-1, CTLA-4, LAG-3, VISTA, TIM-3, TIGIT, or BTLA. In some embodiments, the antigen-binding molecule is administered in combination with an agent capable of promoting signal transduction mediated by a costimulatory receptor. In some embodiments, the costimulatory receptor is, for example, CD28, CD80, CD40L, CD86, OX40, 4-1BB, CD27, or ICOS.

[0485] Accordingly, the present invention provides compositions comprising an article according to the invention (e.g., an antigen-binding molecule according to the invention) and an agent capable of inhibiting signal transduction mediated by an immune checkpoint molecule. Also provided are compositions comprising an article of the invention and an agent capable of promoting signal transduction mediated by a costimulatory receptor. Also provided are uses of such compositions in methods for the medical treatment and prevention of the diseases / conditions described herein.

[0486] Also provided are methods for treating / preventing the diseases / conditions described herein, comprising the steps of administering an article according to the invention (e.g., an antigen-binding molecule according to the invention) and an agent capable of inhibiting signaling mediated by immune checkpoint molecules. Also provided are methods for treating / preventing the diseases / conditions described herein, comprising the steps of administering an article according to the invention (e.g., an antigen-binding molecule according to the invention) and an agent capable of promoting signaling mediated by costimulatory receptors.

[0487] In the art, drugs capable of inhibiting signal transduction mediated by immune checkpoint molecules are known, for example, drugs that bind to immune checkpoint molecules or their ligands and inhibit signal transduction mediated by immune checkpoint molecules. Other agents capable of inhibiting signal transduction mediated by immune checkpoint molecules include agents capable of reducing gene / protein expression of immune checkpoint molecules or ligands for immune checkpoint molecules (e.g., by inhibiting the transcription of the gene(s) encoding the immune checkpoint molecule / ligand, inhibiting post-transcriptional processing of the RNA encoding the immune checkpoint molecule / ligand, reducing the stability of the RNA encoding the immune checkpoint molecule / ligand, promoting the degradation of the RNA encoding the immune checkpoint molecule / ligand, inhibiting post-translational processing of the immune checkpoint molecule / ligand, reducing the stability of the immune checkpoint molecule / ligand, or promoting the degradation of the immune checkpoint molecule / ligand), and small molecule inhibitors.

[0488] Agents capable of promoting signal transduction mediated by costimulatory receptors are known in the art, and include, for example, agonist antibodies capable of binding to costimulatory receptors and inducing or increasing signal transduction mediated by costimulatory receptors. Other agents capable of promoting signal transduction mediated by costimulatory receptors include agents capable of increasing gene / protein expression of costimulatory receptors or ligands for costimulatory receptors (e.g., by promoting the transcription of gene(s) encoding the costimulatory receptor / ligand, promoting post-transcriptional processing of RNA encoding the costimulatory receptor / ligand, increasing the stability of RNA encoding the costimulatory receptor / ligand, inhibiting degradation of RNA encoding the costimulatory receptor / ligand, promoting post-translational processing of the costimulatory receptor / ligand, increasing the stability of the costimulatory receptor / ligand, or inhibiting degradation of the costimulatory receptor / ligand), and small molecule agonists.

[0489] In certain embodiments, the antigen-binding molecules of the invention are administered in combination with an agent capable of inhibiting PD-1-mediated signal transduction. The agent capable of inhibiting PD-1-mediated signal transduction may be a PD-1 targeting agent or a PD-L1 targeting agent. The agent capable of inhibiting PD-1-mediated signal transduction may be, for example, an antibody capable of binding to PD-1 or PD-L1 and inhibiting PD-1-mediated signal transduction.

[0490] In some embodiments, the antigen-binding molecules of the present invention are administered in combination with an agent capable of inhibiting CTLA-4-mediated signal transduction. The agent capable of inhibiting CTLA-4-mediated signal transduction may be a CTLA-4 targeting agent or an agent targeted to a ligand for CTLA-4, such as CD80 or CD86. In some embodiments, the agent capable of inhibiting CTLA-4-mediated signal transduction may be, for example, an antibody capable of binding to CTLA-4, CD80, or CD86 and inhibiting CTLA-4-mediated signal transduction.

[0491] In some embodiments, the antigen-binding molecules of the present invention are administered in combination with an agent capable of inhibiting LAG-3-mediated signal transduction. The agent capable of inhibiting LAG-3-mediated signal transduction may be a LAG-3 targeting agent or an agent targeted to a ligand for LAG-3, such as MHC class II. In some embodiments, the agent capable of inhibiting LAG-3-mediated signal transduction may be, for example, an antibody capable of binding to LAG-3 or MHC class II and inhibiting LAG-3-mediated signal transduction.

[0492] In some embodiments, the antigen-binding molecules of the invention are administered in combination with an agent capable of inhibiting VISTA-mediated signaling. The agent capable of inhibiting VISTA-mediated signaling is a VISTA targeting agent, or The agent may be targeted to a ligand for VISTA, such as VSIG-3 or VSIG-8. In some embodiments, the agent capable of inhibiting VISTA-mediated signaling may be, for example, an antibody capable of binding to VISTA, VSIG-3, or VSIG-8 and inhibiting VISTA-mediated signaling.

[0493] In some embodiments, the antigen-binding molecules of the invention are administered in combination with an agent capable of inhibiting TIM-3-mediated signaling. The agent capable of inhibiting TIM-3-mediated signaling can be a TIM-3 targeting agent or an agent targeted to a ligand for TIM-3, such as galectin 9. In some embodiments, the agent capable of inhibiting TIM-3-mediated signaling can be, for example, an antibody capable of binding to TIM-3 or galectin 9 and inhibiting TIM-3-mediated signaling.

[0494] In some embodiments, the antigen-binding molecules of the present invention are administered in combination with an agent capable of inhibiting TIGIT-mediated signal transduction. The agent capable of inhibiting TIGIT-mediated signal transduction may be a TIGIT targeting agent or an agent targeted to a ligand for TIGIT, such as CD113, CD112, or CD155. In some embodiments, the agent capable of inhibiting TIGIT-mediated signal transduction may be, for example, an antibody capable of binding to TIGIT, CD113, CD112, or CD155 and inhibiting TIGIT-mediated signal transduction.

[0495] In some embodiments, the antigen-binding molecules of the invention are administered in combination with an agent capable of inhibiting BTLA-mediated signal transduction. The agent capable of inhibiting BTLA-mediated signal transduction can be a BTLA targeting agent or an agent targeted to a ligand for BTLA, such as HVEM. In some embodiments, the agent capable of inhibiting BTLA-mediated signal transduction can be, for example, an antibody capable of binding to BTLA or HVEM and inhibiting BTLA-mediated signal transduction.

[0496] In some embodiments, methods utilizing a combination of an antigen-binding molecule of the invention and an agent capable of inhibiting signaling mediated by immune checkpoint molecules (e.g., PD-1) result in an improved treatment effect compared to the effect observed when either agent is used as a monotherapy. In some embodiments, the combination of an antigen-binding molecule of the invention and an agent capable of inhibiting signaling mediated by immune checkpoint molecules (e.g., PD-1) results in a synergistic (i.e., more than additive) treatment effect.

[0497] Concurrent administration refers to the combined administration of an antigen-binding molecule, polypeptide, CAR, nucleic acid (or multiple nucleic acids), expression vector (or multiple expression vectors), cell, or composition with a therapeutic agent, for example, as a pharmaceutical composition (combined preparation) containing both agents, or administration immediately following each other, optionally via the same administration route, for example, into the same artery, vein, or other blood vessel. Sequential administration refers to the separate administration of one of the antigen-binding molecule / composition or therapeutic agent followed by the other agent after a given time interval. It is not required that the two agents be administered by the same route, although this is the case in some embodiments. The time interval can be any time interval.

[0498] Chemotherapy and radiotherapy refer to the treatment of cancer with drugs or ionizing radiation (e.g., radiotherapy using X-rays or gamma rays), respectively. Drugs are chemical entities, e.g. The drug may be a small molecule drug, an antibiotic, a DNA intercalator, a protein inhibitor (e.g., a kinase inhibitor), or a biological agent, such as an antibody, an antibody fragment, an aptamer, a nucleic acid (e.g., DNA, RNA), a peptide, a polypeptide, or a protein. The drug may be formulated as a pharmaceutical composition or medicament. The formulation may include one or more drugs (e.g., one or more active agents) in combination with one or more pharmaceutically acceptable diluents, excipients, or carriers.

[0499] Treatment can involve the administration of more than one drug.Drugs can be administered alone or in combination with other treatments, simultaneously or sequentially, depending on the condition being treated.For example, chemotherapy can be a combination therapy involving the administration of two drugs, one or more of which can be intended to treat cancer.

[0500] Chemotherapy may be administered by one or more routes of administration, for example, parenteral, intravenous injection, oral, subcutaneous, intradermal, or intratumoral routes of administration.

[0501] Chemotherapy can be administered according to treatment regimen. Treatment regimen can be a predetermined timetable, plan, scheme or schedule for chemotherapy administration, which can be created by a doctor or medical professional, and can be fine-tuned to suit the patient who requires treatment. Treatment regimen can indicate one or more of the following: the type of chemotherapy to be administered to the patient; the dose of each drug or the dose of radiation; the time interval between administrations; the length of each treatment; if any, the number and nature of any drug holidays, etc. In combination therapy, a single treatment regimen can be presented, which indicates how each drug should be administered.

[0502] Chemotherapy drugs include abemaciclib, abiraterone acetate, avitrexate (methotrexate), Abraxane (albumin-stabilized nanoparticle formulation of paclitaxel), ABVD, ABVE, ABVE-PC, AC, acalabrutinib, AC-T, Adcetris (brentuximab vedotin), ADE, Ado-trastuzumab emtansine, Adriamycin (doxorubicin hydrochloride), afatinib dimaleate, Afinitor (everolimus), Akynzeo (netupitant and palonosetron hydrochloride), Aldara (imiquimod), aldesleukin, Alecensa (alectinib), alectinib, and alemtuzumab. , Alimta (pemetrexed disodium), Aliqopa (copanlisib hydrochloride), Alkeran injection (melphalan hydrochloride), Alkeran tablets (melphalan), Aloxi (palonosetron hydrochloride), Alunbrig (brigatinib), Ambochlorin (chlorambucil), Amboclorin (chlorambucil), amifostine, aminolevulinic acid, anastrozole, aprepitant, Aredia (pamidronate disodium), Arimidex (anastrozole), Aromasin (exemestane), Arranon (nelarabine), arsenic trioxide, Arzerra (ofatumumab), Erwiniachrysanthemi-derived asparaginase, atezolizumab, Avastin (bevacizumab), avelumab, axicabtagene-ciloleucel, axitinib, azacitidine, Bavencio (avelumab), BEACOPP, Becenum (carmustine), Beleodaq (belinostat), belinstat, bendamustine hydrochloride, BEP, Besponsa (inotuzumab-ozogamicin), bevacizumab, bexarotene, Bexxar (tositumomab and iodine I-131 tositumomab), bicalutamide, Bi CNU (carmustine), bleomycin, blinatumomab, Blincyto (blinatumomab), bortezomib, Bosulif (bosutinib), bosutinib, brentuximab vedotin, brigatinib, BuMel, busulfan, Busulfex (busulfan), cabazitaxel, Cabometyx (cabozantinib-S-malate), cabozantinib-S-malate, CAF, Calquence (acalabrutinib), Camppath (alemtuzumab), Camptosar (irinotecan hydrochloride), capecitabine, C APOX, Carac (topical fluorouracil), carboplatin, carboplatin-TAXOL, carfilzomib, Carmubris (carmustine), carmustine, carmustine implant, Casodex (bicalutamide), CEM, Ceritinib, Cerubidine (daunorubicin hydrochloride), Cervarix (recombinant HPV bivalent vaccine), cetuximab, CEV, chlorambucil, chlorambucil-PREDNISONE, CHOP, cisplatin, cladribine, Clafen (cyclophosphamide), Clorf Farabine, Clofarex (clofarabine), Clolar (clofarabine), CMF, cobimetinib, Cometriq (cabozantinib-S-malate), copanlisib hydrochloride, COPDAC, COPP, COPP-ABV, Cosmegen (dactinomycin), Cotellic (cobimetinib), crizotinib, CVP, cyclophosphamide, Cyfos (ifosfamide), Cyramza (ramucirumab), cytarabine, liposomal cytarabine, Cytosar-U (cytarabine), Cytoxan (cyclophosphamide) , darafenib, dacarbazine, Dacogen (decitabine), dactinomycin, daratumumab, Darzalex (daratumumab), dasatinib, daunorubicin hydrochloride, daunorubicin hydrochloride and liposomal cytarabine, decitabine, defibrotide sodium, Defitelio (defibrotide sodium), degarelix, denileukin diftitox, denosumab, DepoCyt (liposomal cytarabine), dexamethasone, dexrazoxane hydrochloride, dinutuximab, docetaxel, Doxil (doxorubicin hydrochloride liposomal) liposomal), doxorubicin hydrochloride, doxorubicin hydrochloride liposomal, Dox-SL (doxorubicin hydrochloride liposomal), DTIC-Dome (dacarbazine), durvalumab, Efudex (topical fluorouracil), Elitek (rasburicase), Ellence (epirubicin hydrochloride), elotuzumab, Eloxatin (oxaliplatin), eltrombopag olamine, Emend (aprepitant), Empliciti (elotuzumab), enasidenib mesylate, enzalutamide, epirubicin hydrochloride, EPOCH,Erbitux (cetuximab), eribulin mesylate, Erivedge (vismodegib), erlotinib hydrochloride, Erwinaze (Erwinia chrysanthemi-derived asparaginase), Ethyol (amifostine), Etopophos (etoposide phosphate), etoposide, etoposide phosphate, Evacet (doxorubicin hydrochloride liposomal), everolimus, Evista (raloxifene hydrochloride), Evomela (melphalan hydrochloride), exemestane, 5-FU (fluorouracil injection), 5-FU (topical fluorouracil), Fareston (toremifene), Farydak (panobinostat), Faslodex (fulvestrant), FEC, Femara (letrozole), filgrastim, Fludara (fludarabine phosphate), fludarabine phosphate, Fluoroplex (topical fluorouracil), fluorouracil injection, topical fluorouracil, flutamide, Folex (methotrexate), Folex PFS (methotrexate), FOLFIRI, FOLFIRI-bevacizumab, FOLFIRI-cetuximab, FOLFIRINOX, FOLFOX, Folotyn (pralatrexate), FU-LV, fulvestrant, Gardasil (recombinant HPV quadrivalent vaccine), Gardasil 9 (recombinant HPV nonavalent vaccine), Gazyva (obinutuzumab), gefitinib, gemcitabine hydrochloride, gemcitabine-cisplatin, gemcitabine-oxaliplatin, gemtuzumab ozogamicin, Gemzar (gemcitabine hydrochloride), Gilotrif (afatinib dimaleate), Gle evec (imatinib mesylate), Gliadel (carmustine implant), Gliadel wafer (carmustine implant), glucarpidase, goserelin acetate, Halaven (eribulin mesylate), Hemangeol (propranolol hydrochloride), Herceptin (trastuzumab), HPV bivalent vaccine, recombinant HPV nonavalent vaccine, recombinant HPV quadrivalent vaccine, recombinant Hycamtin (topotecan hydrochloride), Hydrea (hydroxyurea), hydroxyurea, Hyper-CVAD, Ibrance (palbociclib), ibritumomab tiuxetan,Ibrutinib、ICE、I、 clusig (ponatinib hydrochloride), Idamycin (idarubicin hydrochloride), idarubicin hydrochloride, idelalisib, Idhifa (enasidenib mesylate), Ifex (ifosfamide), ifosfamide, Ifosfamidum (ifosfamide), IL-2 (aldesleukin), imatinib mesylate, Imbruvica (ibrutinib), Imfinzi (durvalumab), imiquimod, Imlygic (talimogen laherparepvec), Inlyta (axitinib), inotuzumab ozogamicin, interferon alfa-2b, recombinant, interleukin-2 (aldesleukin), Intron A (recombinant interferon alpha-2b), iodine I-131 tositumomab and tositumomab, ipilimumab, Iressa (gefitinib), irinotecan hydrochloride, irinotecan hydrochloride liposomal, Istodax (romidepsin), ixabepilone, ixazomib citrate, Ixempra (ixabepilone), Jakafi (ruxolitinib), JEB, Jevtan a (cabazitaxel), Kadcyla (Ado-trastuzumab emtansine), Keoxifene (raloxifene hydrochloride), Kepivance (palifermin), Keytruda (pembrolizumab), Kisqali (ribociclib), Kymriah (tisagenlecleucel), Kyprolis (carfilzomib), lanreotide acetate, lapatinib ditosylate, La rtruvo (olaratumab), lenalidomide, lenvatinib mesylate, Lenvima (lenvatinib mesylate), letrozole, leucovorin calcium, Leukeran (chlorambucil), leuprolide acetate, Leustatin (cladribine), Levulan (aminolevulinic acid), Linfolizin (chlorambucil), LipoDox (liposomal doxorubicin hydrochloride), lomustine, Lonsurf (trifluridine and tipiracil hydrochloride), Lupron (leuprolide acetate), Lupron Depot (leuprolide acetate), Lupron Pediatric Depot (leuprolide acetate), Lynparza (olaparib), Marqibo (liposomal vincristine sulfate), Matulane (procarbazine hydrochloride), mechlorethamine hydrochlorideMegestrol acetate, Mekinist (trametinib), melphalan, melphalan hydrochloride, mercaptopurine, mesna, Mesnex (mesna), Methazolastone (temozolomide), methotrexate, methotrexate LPF (methotrexate), methylnaltrexone bromide, Mexate (methotrexate), Mexate-AQ (methotrexate), midostaurin, mitomycin C, mitoxantrone hydrochloride, Mitozytrex (mitomycin C), MOPP, Mozobil (plerixafor), M ustargen (mechlorethamine hydrochloride), Mutamycin (mitomycin C), Myleran (busulfan), Mylosar (azacytidine), Mylotarg (gemtuzumab ozogamicin), nanoparticle paclitaxel (albumin-stabilized nanoparticle formulation of paclitaxel), navelbine (vinorelbine tartrate), necitumumab, nelarabine, Neosar (cyclophosphamide), neratinib maleate, Nerlynx (neratinib maleate), netupitant and palonosetron hydrochloride, Neulasta (pegfil) rastim), Neupogen (filgrastim), Nexavar (sorafenibut tosylate), Nilandron (nilutamide), nilotinib, nilutamide, Ninlaro (ixazomib citrate), niraparibut tosilate monohydrate, nivolumab, Nolvadex (tamoxifen citrate), Nplate (romiplostim), obinutuzumab, Odomzo (sonidegib), OEPA, ofatumumab, OFF, olaparib, olaratumab, omacetaxine mepesuccinate, Oncaspar (pegaspargase), ondancetro hydrochloride, Onivyde (irinotecan hydrochloride liposomal formulation), Ontak (denileukin diftitox), Opdivo (nivolumab), OPPA, osimertinib, oxaliplatin, paclitaxel, albumin-stabilized nanoparticle formulation of paclitaxel, PAD, palbociclib, palifermin, palonosetron hydrochloride, palonosetron hydrochloride and netupitant, pamidronate disodium, panitumumab, panobinostat, Paraplat (carboplatin), Paraplatin (carboplatin), pazopanib hydrochloride, PCV,PEB, Pe, Gaspargase, pegfilgrastim, PEG interferon alfa-2b, PEG -Intron (pegylated interferon alfa-2b), pembrolizumab, pemetrexed disodium, Perjeta (pertuzumab), pertuzumab, Platinol (cisplatin), Platinol-AQ (cisplatin), plerixafor, pomalidomide, Pomalyst (pomalidomide), ponatinib hydrochloride, Portrazza (necitumumab), pralatrexate, prednisone, procarbazine hydrochloride, Proleukin (Aldesro) Ikin), Prolia (denosumab), Promacta (eltrombopagulamine), propranolol hydrochloride, Provenge (sipuleucel-T), Purinethol (mercaptopurine), Purixan (mercaptopurine), [unspecified], radium-223 dichloride, raloxifene hydrochloride, ramucirumab, rasburicase, R-CHOP, R-CVP, recombinant human papillomavirus (HPV) bivalent vaccine, recombinant human papillomavirus (HPV) nine tetravalent vaccine, recombinant human papillomavirus (HPV) quadrivalent vaccine, recombinant interferon alfa-2b, regorafenib, Relistor (methylnaltrexone bromide), R-EPOCH, Revlimid (lenalidomide), Rheumatrex (methotrexate), ribociclib, R-ICE, Rituxan (rituximab), RituxanHycela (rituximab and human hyaluronidase), rituximab, rituximab and human hyaluronidase Lonidase, rolapitant hydrochloride, romidepsin, romiplostim, Rubidomycin (daunorubicin hydrochloride), Rubraca (rucaparib camsylate), rucaparib camsylate, ruxolitinib phosphate, Rydapt (midostaurin), sclerosol intrapleural aerosol (talc), siltuximab, sipuleucel-T, somatulin depot (lanreotide acetate), sonidegib, sorafenib tosylate, Sprycel (dasatinib), STANFORDV, Sterile Talc Powder (Talc), Steritalc (Talc), Stivarga (Regorafenib), Sunitinib Malate, Sutent (Sunitinib Malate), Sylatron (Peg-Interferon Alfa-2b), Sylvant (Siltuximab), Synribo (Omacetaxine Mepesuccinate), Tabloid (Thioguanine), TAC, Tafinlar (Darafenib), Tagrisso (Osimertinib), Talc, Talimogen Laherparepvec, Tamoxifen Citrate, Tarabine PFS (cytarabine), Tarceva (erlotinib hydrochloride), Targretin (bexarotene), Tasigna (nilotinib), Taxol (paclitaxel), Taxotere (docetaxel), Tecentriq (atezolizumab), Temodar (temozolomide), temozolomide, temsirolimus, thalidomide, Thalomid (thalidomide), thioguanine, thiotepa, tisagenlecleucel, Tolak (topical fluorouracil), topotecan hydrochloride, toremifene, Torisel (temsirolimus), tositumomab and iodine I-131 tositumomab, Totect (dexrazoxane hydrochloride), TPF, Trabectedin, trametinib, trastuzumab, Treanda (bendamustine hydrochloride), trifluridine and tipiracil hydrochloride, Trisenox (arsenic trioxide), Tykerb (lapatinib ditosylate), Unituxin (dinutuximab), uridine triacetate, VAC, valrubicin, Valstar (valrubicin), vandetanib, VAMP, Varubi (rolapitant hydrochloride), Vectibix (panitumumab), VeIP, Velban (vinblastine sulfate), Velcade (bortezomib), V elsar (vinblastine sulfate), vemurafenib, Venclexta (venetoclax), venetoclax, Verzenio (abemaciclib), Viadur (leuprolide acetate), Vidaza (azacitidine), vinblastine sulfate, Vincasar PFS (vincristine sulfate), vincristine sulfate, vincristine sulfate liposomal, vinorelbine tartrate, VIP, vismodegib, Vistogard (uridine triacetate), Voraxaze (glucarpidase), vorinostat, Votrient (pazopanib hydrochloride), Vyxeos (daunorubicin hydrochloride and cytarabine liposomal), Wellcovorin (leucovorin calcium), Xalkori (crizotinib), Xeloda (capecitabine), XELIRI, XELOX, Xgeva (denosumab), Xofigo (radium-223 dichloride), Xtandi (enzalutamide), Yervoy (ipilimumab), Yescarta (akikinase) The agent may be selected from cicabtagene ciloleucel), Yondelis (trabectodin), Zaltrap (Ziv-aflibercept), Zarxio (filgrastim), Zejula (niraparibut tosylate monohydrate), Zelboraf (vemurafenib), Zevalin (ibritumomab tiuxetan), Zinecard (dexrazoxane hydrochloride), Ziv-aflibercept, Zofran (ondansetron hydrochloride), Zoladex (goserelin acetate), zoledronic acid, Zolinza (vorinostat), Zometa (zoledronic acid), Zydelig (idelalisib), Zykadia (ceritinib), and Zytiga (abiraterone acetate).

[0503] In some embodiments, antigen-binding molecules of the present invention are administered in combination with one or more of trastuzumab, cetuximab, cisplatin, 5-FU, or capecitabine. In some embodiments, antigen-binding molecules of the present invention are administered in combination with trastuzumab and cisplatin, as well as 5-FU or capecitabine.

[0504] In some embodiments, the antigen-binding molecules of the present invention are administered in combination with cetuximab. In particular, administration in combination with cetuximab is contemplated for the treatment of head and neck cancer (e.g., head and neck squamous cell carcinoma).

[0505] Multiple administrations of the antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), cell(s), or composition may be given, and one or more, or each administration may be accompanied by the simultaneous or sequential administration of another therapeutic agent.

[0506] The multiple administrations may be separated by a predetermined time interval, which may be selected to be one of 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, or 31 days, or 1, 2, 3, 4, 5, or 6 months. By way of example, administrations may be given every 7, 14, 21, or 28 days (± 3, 2, or 1 day). Detection method The invention also provides an article of the invention for use in a method of detecting, localizing, or imaging HER3, or cells expressing HER3.

[0507] The antigen-binding molecules described herein can be used in methods involving antigen-binding molecules directed against HER3. Such methods can involve detection of a binding complex between the antigen-binding molecule and HER3.

[0508] Thus, the steps of contacting a sample containing or suspected of containing HER3 and detecting the formation of a complex between the antigen-binding molecule and HER3 are performed. Also provided is a method comprising contacting a sample containing or suspected of containing cells that express HER3 with an antigen-binding molecule and detecting the formation of a complex between the cells that express HER3.

[0509] Suitable method formats are well known in the art, including sandwich assays, for example, immunoassays such as ELISA. The method may involve labeling the antigen-binding molecule, or the target(s), or both, with a detectable moiety, such as a fluorescent label, a phosphorescent label, a luminescent label, an immunodetectable label, a radioactive label, a chemical label, a nucleic acid label, or an enzyme label, as described herein. Detection methods are well known to those skilled in the art and can be selected to correspond to the labeling agent.

[0510] Such methods can provide the basis for diagnostic and / or prognostic evaluation of diseases or conditions, such as cancer. Such methods may be performed on patient samples in vitro, or may be performed after processing of the patient sample. Once the sample is collected, the patient is not required to be present during the in vitro method, and thus the methods are not performed within a human or animal body. In some embodiments, the methods are performed in vivo.

[0511] Detection in a sample may be used for diagnostic purposes of a disease / condition (e.g., cancer), a predisposition to a disease / condition, or may be used to prognose (predict) a disease / condition, such as a disease / condition described herein. The diagnosis or prognosis may be for an existing (already diagnosed) disease / condition.

[0512] Such methods may involve, for example, detecting or quantifying HER3 or cells expressing HER3 in a patient sample. When a method includes quantifying a factor of interest, the method may further include comparing the determined amount to a standard or reference value as part of a diagnostic or prognostic evaluation. Other diagnostic / prognostic tests may be used in conjunction with the diagnostic / prognostic tests described herein to enhance the accuracy of diagnosis or prognosis or to confirm the results obtained by using the tests described herein.

[0513] A sample can be taken from any tissue or body fluid. The sample can include or be derived from a volume of blood; a volume of serum derived from an individual's blood, which can include the fluid portion of blood obtained after removing fibrin clots and blood cells; a tissue sample or biopsy; pleural effusion; cerebrospinal fluid (CSF); or cells isolated from said individual. In some embodiments, the sample can be obtained from or be derived from a tissue or tissues affected by a disease / condition (e.g., a tissue or tissues in which a symptom of the disease is manifested or which are involved in the pathogenesis of the disease / condition).

[0514] The present invention also provides methods for selecting / stratifying subjects for treatment with a HER3 targeting agent. In some embodiments, a subject is selected for treatment / prevention according to the present invention, or is identified as a subject who would benefit from such treatment / prevention, for example, based on detection / quantification of HER3 or cells expressing HER3 in a sample obtained from the individual. subject The subject according to the aspects of the invention described herein can be any animal or human. The subject is preferably a mammal, more preferably a human. The subject can also be a non-human mammal, but is more preferably a human. The subject can be male or female. The subject can be a patient. The subject can be diagnosed with a disease or condition (e.g., cancer) that requires treatment, or can be suspected of having such a disease / condition. In some cases, a person may be at risk of developing or suffering from such a disease / condition.

[0515] In embodiments according to the present invention, the subject is preferably a human subject. In some embodiments, the subject treated according to the therapeutic or preventive methods of the present invention herein is a subject who has cancer or is at risk of developing cancer. In embodiments according to the present invention, the subject can be selected for treatment according to a method based on the characterization of certain markers of such diseases / conditions. kit In some aspects of the present invention, a kit of parts as described herein is provided. In some embodiments, the kit may include at least one container containing a predetermined quantity of an antigen-binding molecule, polypeptide, CAR, nucleic acid (or nucleic acids), expression vector (or expression vectors), cell, or composition as described herein.

[0516] In some embodiments, the kit may include materials for making an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), cell, or composition described herein.

[0517] The kit may provide an antigen-binding molecule, polypeptide, CAR, nucleic acid(s), expression vector(s), cell(s), or composition together with instructions for administration to a patient to treat a specified disease / condition.

[0518] In some embodiments, the kit may further include at least one container having a predetermined quantity of another therapeutic agent (e.g., an anti-infective or chemotherapeutic agent). In such embodiments, the kit may also include a second medicament or pharmaceutical composition such that the two medicaments or pharmaceutical compositions can be administered simultaneously or separately to provide a combined treatment for a specific disease or condition. The therapeutic agent may also be formulated to be suitable for injection or infusion into a tumor or blood. Sequence identity As used herein, "sequence identity" refers to the percentage of nucleotides / amino acid residues in a subject sequence that are identical to nucleotides / amino acid residues in a reference sequence, after aligning the sequences and introducing gaps, if necessary, to achieve the maximum percent sequence identity between the sequences. Pairwise, multiple sequence alignments for determining the percent sequence identity between two or more amino acid or nucleic acid sequences can be accomplished in a variety of ways known to those skilled in the art using commercially available computer software, such as ClustalOmega (Soding, J. 2005, Bioinformatics, 21, 951-960), T-coffee (Notredame et al., 2000, J. Mol. Biol. (2000), 302, 205-217), Kalign (Lassmann and Sonnhammer, 2005, BMC Bioinformatics, 6(298)), and MAFFT (Katoh and Standley, 2013, Molecular Biology and Evolution, 30(4), 772-780). When using such software, it is preferred to use default parameters, for example, for gap penalties and extension penalties.

[0519] [Table 2-1]

[0520] [Table 2-2]

[0521] [Table 2-3]

[0522] [Table 2-4]

[0523] Table 2-5

[0524] Table 2-6

[0525] Table 2-7

[0526] Table 2-8

[0527] Table 2-9

[0528] Table 2-10

[0529] Table 2-11

[0530] Table 2-12

[0531] Table 2-13

[0532] Table 2-14

[0533] Table 2-15

[0534] [Table 2-16]

[0535] [Table 2-17]

[0536] [Table 2-18] Numbered Items The following numbered paragraphs (para) provide further statements about features and combinations of features that are contemplated in the context of the present invention: 1. An antigen-binding molecule, optionally an isolated antigen-binding molecule, capable of binding to HER3 within the extracellular region subdomain II.

[0537] 2. The antigen-binding molecule of item 1, which inhibits the interaction between HER3 and an interaction partner of HER3.

[0538] 3. The antigen-binding molecule of item 1 or item 2, which is capable of binding to a polypeptide comprising or consisting of the amino acid sequence of SEQ ID NO: 16.

[0539] 4. The antigen-binding molecule of any one of items 1 to 3, which is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO: 23 or SEQ ID NO: 229.

[0540] 5. The antigen-binding molecule of any one of items 1 to 4, which is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO: 21 or SEQ ID NO: 229.

[0541] 6.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 43 HC-CDR2 having the amino acid sequence of SEQ ID NO: 46 HC-CDR3 having the amino acid sequence of SEQ ID NO: 51 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 91 LC-CDR2 having the amino acid sequence of SEQ ID NO: 94 LC-CDR3 having the amino acid sequence of SEQ ID NO: 99 Light chain variable (VL) region incorporating 6. The antigen-binding molecule of any one of items 1 to 5, comprising:

[0542] 7.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0543] 8.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 89 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0544] 9.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 90 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 96 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0545] 10.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 98 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0546] 11.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0547] 12.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 49 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0548] 13.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 50 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0549] 14.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0550] 15.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 97 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0551] 16.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 42 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 Light chain variable (VL) region incorporating 7. The antigen-binding molecule of any one of items 1 to 6, comprising:

[0552] 17.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 158 HC-CDR2 having the amino acid sequence of SEQ ID NO: 159 HC-CDR3 having the amino acid sequence of SEQ ID NO: 160 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 165 LC-CDR2 having the amino acid sequence of SEQ ID NO: 166 LC-CDR3 having the amino acid sequence of SEQ ID NO: 167 Light chain variable (VL) region incorporating 6. The antigen-binding molecule of any one of items 1 to 5, comprising:

[0553] 18. The antigen-binding molecule of any one of items 1 to 4, which is capable of binding to a polypeptide comprising the amino acid sequence of SEQ ID NO: 22.

[0554] 19.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 128 HC-CDR2 having the amino acid sequence of SEQ ID NO: 129 HC-CDR3 having the amino acid sequence of SEQ ID NO: 130 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 136 LC-CDR2 having the amino acid sequence of SEQ ID NO: 137 LC-CDR3 having the amino acid sequence of SEQ ID NO: 138 Light chain variable (VL) region incorporating 19. The antigen-binding molecule of any one of items 1 to 4 or item 18, comprising:

[0555] 20.(i) The following CDR: HC-CDR1 having the amino acid sequence of SEQ ID NO: 144 HC-CDR2 having the amino acid sequence of SEQ ID NO: 145 HC-CDR3 having the amino acid sequence of SEQ ID NO: 146 a heavy chain variable (VH) region incorporating (ii) the following CDR: LC-CDR1 having the amino acid sequence of SEQ ID NO: 151 LC-CDR2 having the amino acid sequence of SEQ ID NO: 152 LC-CDR3 having the amino acid sequence of SEQ ID NO: 153 Light chain variable (VL) region incorporating 19. The antigen-binding molecule of any one of items 1 to 4 or item 18, comprising:

[0556] 21. (i) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 24; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 74; or (ii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 25; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 75; or (iii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 26; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 76; or (iv) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 27; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 77; or (v) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 28; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (vi) having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 29 a VH region comprising an amino acid sequence a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (vii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 30; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (viii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 31; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 79; or (ix) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 32; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 79; or (x) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 33; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 80; or (xi) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 34; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 81; or (xii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 35; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 82; or (xiii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 36; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 83; or (xiv) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 37; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 84; or (xv) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 38; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 85; or (xvi) having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 39 a VH region comprising an amino acid sequence corresponding to a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 86; or (xvii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 40; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 87; or (xviii) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 127; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 135; or (xix) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 143; and a VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 150; or (xx) a VH region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 157; and A VL region comprising an amino acid sequence having at least 70% sequence identity to the amino acid sequence of SEQ ID NO: 164. 5. The antigen-binding molecule of any one of items 1 to 4, comprising:

[0557] 22. The antigen-binding molecule of any one of items 1 to 21, which is capable of binding to human HER3, and one or more of mouse HER3, rat HER3, and cynomolgus monkey HER3.

[0558] 23. An antigen-binding molecule, optionally an isolated antigen-binding molecule, comprising: (i) the antigen-binding molecule of any one of items 1 to 22; and (ii) an antigen-binding molecule capable of binding to an antigen other than HER3.

[0559] 24. The antigen-binding molecule of any one of items 1 to 23, which is capable of binding to the cell surface of a cell expressing HER3.

[0560] 25. The antigen-binding molecule of any one of items 1 to 24, which is capable of inhibiting HER3-mediated signaling.

[0561] 26. The antigen-binding molecule of any one of items 1 to 25, comprising an Fc region, wherein the Fc region comprises a polypeptide having one or more of: (i) a C at a position corresponding to 242 and a C at a position corresponding to 334; and (ii) an A at a position corresponding to 236, a D at a position corresponding to 239, an E at a position corresponding to 332, an L at a position corresponding to 330, a K at a position corresponding to 345, and a G at a position corresponding to 430.

[0562] 27. The antigen-binding molecule of item 26, wherein the Fc region comprises a polypeptide having a C at a position corresponding to 242, a C at a position corresponding to 334, an A at a position corresponding to 236, a D at a position corresponding to 239, an E at a position corresponding to 332, and an L at a position corresponding to 330.

[0563] 28. A chimeric antigen receptor (CAR) comprising the antigen-binding molecule of any one of items 1 to 27.

[0564] 29. One or more nucleic acids, optionally one isolated nucleic acid or multiple isolated nucleic acids, encoding the antigen-binding molecule of any one of items 1 to 27 or the CAR of item 28.

[0565] 30. An expression vector or vectors comprising the nucleic acid or nucleic acids according to item 29.

[0566] 31. A cell comprising the antigen-binding molecule of any one of items 1 to 27, the CAR of item 28, the nucleic acid or nucleic acids of item 29, or the expression vector or vectors of item 30.

[0567] 32. A method comprising culturing a cell containing the nucleic acid or nucleic acids of item 29, or the expression vector or vectors of item 30, under conditions suitable for expression of the antigen-binding molecule or CAR from the nucleic acid(s) or expression vector(s).

[0568] 33. A composition comprising the antigen-binding molecule of any one of items 1 to 27, the CAR of item 28, the nucleic acid or nucleic acids of item 29, the expression vector or expression vectors of item 30, or the cell of item 31.

[0569] 34. The antigen-binding molecule of any one of items 1 to 27, the CAR of item 28, the nucleic acid or nucleic acids of item 29, the expression vector or vectors of item 30, the cell of item 31, or the composition of item 33 for use in a method of medical treatment or prophylaxis.

[0570] 35. The antigen-binding molecule of any one of items 1 to 27, the CAR of item 28, the nucleic acid or nucleic acids of item 29, the expression vector or vectors of item 30, the cell of item 31, or the composition of item 33 for use in a method for treating or preventing cancer.

[0571] 36. Use of an antigen-binding molecule according to any one of items 1 to 27, a CAR according to item 28, a nucleic acid or nucleic acids according to item 29, an expression vector or expression vectors according to item 30, a cell according to item 31, or a composition according to item 33 in the manufacture of a medicament for use in a method for treating or preventing cancer.

[0572] 37. A method for treating or preventing cancer, comprising administering to a subject a therapeutically or prophylactically effective amount of the antigen-binding molecule of any one of items 1 to 27, the CAR of item 28, the nucleic acid or nucleic acids of item 29, the expression vector or vectors of item 30, the cell of item 31, or the composition of item 33.

[0573] 38. An antigen-binding molecule, CAR, nucleic acid or nucleic acids for the use of item 34 or item 35, the use of item 36, or the method of item 37, wherein the method further comprises administering an inhibitor of signal transduction mediated by an EGFR family member, and optionally the inhibitor of signal transduction mediated by an EGFR family member is an inhibitor of signal transduction mediated by HER2 and / or EGFR. An expression vector or vectors, a cell, or a composition.

[0574] 39. The cancer is cancer containing cells that express EGFR family members, cancer containing cells that express HER3, solid tumor, breast cancer, breast cancer, ductal carcinoma, gastric cancer, gastric...

Claims

1. Use of an antigen-binding molecule comprising a heavy chain variable (VH) region and a light chain variable (VL) region in the manufacture of a medicament for use in a method for treating or preventing lung cancer, wherein the antigen-binding molecule specifically binds to HER3, and binding to HER3 comprises contact with a region of HER3 set forth in SEQ ID NO:

229.

2. 2. The use of claim 1, wherein the lung cancer is selected from non-small cell lung cancer (NSCLC), lung adenocarcinoma, and squamous cell lung carcinoma.

3. The antigen-binding molecule comprises the following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 43 HC-CDR2 having the amino acid sequence of SEQ ID NO: 46 HC-CDR3 having the amino acid sequence of SEQ ID NO:51 a VH region incorporating The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 91 LC-CDR2 having the amino acid sequence of SEQ ID NO: 94 LC-CDR3 having the amino acid sequence of SEQ ID NO: 99 VL region incorporating 3. The use according to claim 1 or 2, comprising:

4. The antigen-binding molecule (a) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 or a VL region having (b) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 89 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 or a VL region having (c) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 90 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 96 or a VL region having (d) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 or a VL region having (e) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO:49 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 or a VL region having (f) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 50 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 93 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 or a VL region having (g) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 97 or a VL region having (h) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 42 HC-CDR2 having the amino acid sequence of SEQ ID NO: 45 HC-CDR3 having the amino acid sequence of SEQ ID NO: 48 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 95 or a VL region having (i) The following CDRs: HC-CDR1 having the amino acid sequence of SEQ ID NO: 41 HC-CDR2 having the amino acid sequence of SEQ ID NO: 44 HC-CDR3 having the amino acid sequence of SEQ ID NO: 47 and a VH region having The following CDRs: LC-CDR1 having the amino acid sequence of SEQ ID NO: 88 LC-CDR2 having the amino acid sequence of SEQ ID NO: 92 LC-CDR3 having the amino acid sequence of SEQ ID NO: 98 A VL region having 4. The use according to any one of claims 1 to 3, comprising:

5. The antigen-binding molecule (a) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 24; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 74; or (b) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 25; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 75; or (c) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 26; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 76; or (d) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 27; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 77; or (e) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 28; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (f) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 29; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (g) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 30; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 78; or (h) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 31; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 79; or (i) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 32; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 79; or (j) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 33; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 80; or (k) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 34; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 81; or (l) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 35; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 82; or (m) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 36; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 83; or (n) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 37; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 84; or (o) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 38; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 85; or (p) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 39; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 86; or (q) a VH region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO: 40; and a VL region comprising an amino acid sequence having at least 90% sequence identity to the amino acid sequence of SEQ ID NO:

87.

5. The use according to claim 3 or 4, comprising:

6. The antigen-binding molecule (a) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 55 HC-FR2 having the amino acid sequence of SEQ ID NO: 58 HC-FR3 having the amino acid sequence of SEQ ID NO: 69 HC-FR4 having the amino acid sequence of SEQ ID NO: 73 or a VH region incorporating (b) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 56 HC-FR3 having the amino acid sequence of SEQ ID NO: 61 HC-FR4 having the amino acid sequence of SEQ ID NO: 70 or a VH region incorporating (c) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 56 HC-FR3 having the amino acid sequence of SEQ ID NO: 62 HC-FR4 having the amino acid sequence of SEQ ID NO: 70 or a VH region incorporating (d) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 57 HC-FR3 having the amino acid sequence of SEQ ID NO: 62 HC-FR4 having the amino acid sequence of SEQ ID NO: 70 or a VH region incorporating (e) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 224 HC-FR2 having the amino acid sequence of SEQ ID NO: 60 HC-FR3 having the amino acid sequence of SEQ ID NO: 63 HC-FR4 having the amino acid sequence of SEQ ID NO: 70 or a VH region incorporating (f) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 56 HC-FR3 having the amino acid sequence of SEQ ID NO: 64 HC-FR4 having the amino acid sequence of SEQ ID NO: 70 or a VH region incorporating (g) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 57 HC-FR3 having the amino acid sequence of SEQ ID NO: 64 HC-FR4 having the amino acid sequence of SEQ ID NO: 70 or a VH region incorporating (h) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 52 HC-FR2 having the amino acid sequence of SEQ ID NO: 56 HC-FR3 having the amino acid sequence of SEQ ID NO: 65 HC-FR4 having the amino acid sequence of SEQ ID NO: 70 or a VH region incorporating (i) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 53 HC-FR2 having the amino acid sequence of SEQ ID NO:59 HC-FR3 having the amino acid sequence of SEQ ID NO: 66 HC-FR4 having the amino acid sequence of SEQ ID NO: 71 or a VH region incorporating (j) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 54 HC-FR2 having the amino acid sequence of SEQ ID NO:59 HC-FR3 having the amino acid sequence of SEQ ID NO: 67 HC-FR4 having the amino acid sequence of SEQ ID NO: 71 or a VH region incorporating (k) The following framework regions (FR): HC-FR1 having the amino acid sequence of SEQ ID NO: 53 HC-FR2 having the amino acid sequence of SEQ ID NO:59 HC-FR3 having the amino acid sequence of SEQ ID NO: 68 HC-FR4 having the amino acid sequence of SEQ ID NO: 72 A VH region incorporating The use according to any one of claims 1 to 5, comprising:

7. The antigen-binding molecule (a) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 106 LC-FR2 having the amino acid sequence of SEQ ID NO: 113 LC-FR3 having the amino acid sequence of SEQ ID NO: 123 LC-FR4 having the amino acid sequence of SEQ ID NO: 126 or a VL region incorporating (b) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 100 LC-FR2 having the amino acid sequence of SEQ ID NO: 107 LC-FR3 having the amino acid sequence of SEQ ID NO: 114 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 or a VL region incorporating (c) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 101 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 115 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 or a VL region incorporating (d) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 102 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 116 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 or a VL region incorporating (e) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 103 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 117 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 or a VL region incorporating (f) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 103 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 118 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 or a VL region incorporating (g) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 103 LC-FR2 having the amino acid sequence of SEQ ID NO: 109 LC-FR3 having the amino acid sequence of SEQ ID NO: 119 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 or a VL region incorporating (h) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 104 LC-FR2 having the amino acid sequence of SEQ ID NO: 110 LC-FR3 having the amino acid sequence of SEQ ID NO: 120 LC-FR4 having the amino acid sequence of SEQ ID NO: 125 or a VL region incorporating (i) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 105 LC-FR2 having the amino acid sequence of SEQ ID NO: 110 LC-FR3 having the amino acid sequence of SEQ ID NO: 121 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 or a VL region incorporating (j) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 104 LC-FR2 having the amino acid sequence of SEQ ID NO: 111 LC-FR3 having the amino acid sequence of SEQ ID NO: 122 LC-FR4 having the amino acid sequence of SEQ ID NO: 125 or a VL region incorporating (k) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 100 LC-FR2 having the amino acid sequence of SEQ ID NO: 112 LC-FR3 having the amino acid sequence of SEQ ID NO: 114 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 or a VL region incorporating (l) The following framework regions (FR): LC-FR1 having the amino acid sequence of SEQ ID NO: 103 LC-FR2 having the amino acid sequence of SEQ ID NO: 108 LC-FR3 having the amino acid sequence of SEQ ID NO: 119 LC-FR4 having the amino acid sequence of SEQ ID NO: 124 VL region incorporating 7. The use according to any one of claims 1 to 6, comprising:

8. The use according to any one of claims 1 to 7, wherein the antigen-binding molecule comprises the heavy chain constant sequence of SEQ ID NO:

171.

9. The use according to any one of claims 1 to 8, wherein the antigen-binding molecule comprises the light chain constant sequence of SEQ ID NO: 177.

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