Humanized CLDN18.2 antibody

Abstract

The present invention provides a humanized antibody that binds to CLDN18.2 with high affinity. This antibody does not exhibit cross-reactivity with CLDN18.1. Furthermore, the present invention provides nucleic acids, vectors, host cells, and medical uses.

Description

[Background technology]

[0001] Tight junctions are multiprotein complexes that connect adjacent epithelial and endothelial cells to form a barrier that prevents the passage of molecules between cells and helps maintain cell and tissue polarity. Tight junctions consist of three main groups of transmembrane proteins, claudins, occludin, and cingulin, of which claudins and occludin are intracellular plaque proteins. Tight junctions also contain cytoskeletal and signaling proteins, e.g., actin, myosin II, and PKCζ. These proteins interact to maintain the structure of the tight junctions (Yu and Turner, 2008).

[0002] Claudins constitute a family of 23 proteins (Hewitt, Agarwal, and Morin, 2006). Claudin 18 is a human protein encoded by the CLDN18 gene, which forms tight junction strands in epithelial cells. Human CLDN18 is produced by alternative splicing of the first two alternative exons, resulting in two protein isoforms, CLDN18.1 (claudin 18.1) and CLDN18.2 (claudin 18.2). CLDN18.2 was originally disclosed as the Zsig28 protein in WO2000 / 015659. These two isoforms differ in the amino acid sequence of the N-terminal 69 residues, which includes the first extracellular loop. This first extracellular domain consists of amino acids 28-80. In this amino acid sequence, CLDN18.1 and CLDN18.2 differ by eight amino acids. These two isoforms are expressed in different tissues. CLDN18.1 is mainly expressed in lung tissues, whereas CLDN18.2 is specifically expressed in the stomach (Niimi et al., 2001). CLDN18.2 expression in normal stomach is found only in differentiated, short-lived gastric epithelial cells. Furthermore, CLDN18.2 expression has also been identified in various tumor tissues. For example, CLDN18.2 has been found to be expressed in pancreatic, esophageal, ovarian and lung tumors, and is associated with the presence of various histological subtypes (Sahin et al., 2008).

[0003] CLDN18.2 has attracted attention as a general cancer target for antibody therapy of epithelial tumors because its expression pattern in normal tissues is restricted to certain cells and it is ectopically expressed in human cancers. Various studies have been conducted to realize such antibody therapy. In WO2004 / 047863, splice variants of CLDN18 have been identified, and antibodies against various peptides derived from CLDN18.2 have been screened. In this screening, the following peptides derived from CLDN18.2 were used: a peptide consisting of DQWSTQDLYN (SEQ ID NO: 68) (the N-terminal extracellular domain of CLDN18.2, the antibody binds regardless of the presence or absence of glycosylation); a peptide consisting of NNPVTAVFNYQ (SEQ ID NO: 69) (the N-terminal extracellular domain of CLDN18.2, the antibody binds mainly to the non-glycosylated form); and a peptide consisting of STQDLYNNPVTAVF (SEQ ID NO: 70) (the N-terminal extracellular domain of CLDN18.2, the antibody binds only to the non-glycosylated form). Furthermore, this patent document also discloses polyclonal rabbit antibodies screened using a pan-CLDN18 peptide consisting of TNFWMSTANMYTG (SEQ ID NO: 71) contained in the C-terminal extracellular domain common to both the CLDN18.1 and CLDN18.2 isoforms. WO2005 / 113587 discloses antibodies against a specific epitope of CLDN18.2 defined by the peptide sequence ALMIVGIVLGAIGLLV (SEQ ID NO: 72) or RIGSMEDSAKANMTLTSGIMFIVS (SEQ ID NO: 73). WO2007 / 059997 discloses a CLDN18.2-specific monoclonal antibody obtained by immunization with a peptide consisting of METDTLLLWVLLLWVPGSTGDAAQPARRARRTKLGTELGSTPVWWNSADGRMDQWSTQDLYNNPVTAVFNYQGLWRSCVRESSGFTECRGYFTLLGLPAMLQAVRAAIQHSGGRSRRARTKTHLRRGSE (SEQ ID NO: 74) (comprising the first extracellular domain of CLDN18.2 extended at the N-terminus and C-terminus).The antibodies obtained by this immunization exert cytotoxicity via complement-dependent cytotoxicity (CDC) and antibody-dependent cell-mediated cytotoxicity (ADCC). WO2007 / 059997 and WO2016 / 165762 disclose an antibody called IMAB362, also known as Claudiximab or Zolbetuximab. IMAB362 is an IgG1 antibody derived from a mouse monoclonal antibody, and for clinical application, a human IgG1 constant region has been introduced by chimerization. WO2008 / 145338 discloses various antibodies that bind to overlapping peptides in the first extracellular domain (MDQWSTQDLYNNPVT (SEQ ID NO: 75), LYNNPVTAVFNYQGL (SEQ ID NO: 76), VFNYQGLWRSCVRES (SEQ ID NO: 77), QGLWRSCVRESSGFT (SEQ ID NO: 78) and RSCVRESSGFTECRG (SEQ ID NO: 79)). WO2013 / 167259 also attempts to produce an antibody targeting the C-terminal portion of CLDN18.2 in order to detect the expression of CLDN18.2 in cells in cancer tissue sections for diagnostic purposes, and discloses an antibody that binds to the C-terminal epitope of CLDN18.2. This patent document discloses two C-terminal epitopes of CLDN18.2, a sequence consisting of TEDEVQSYPSKHDYV (SEQ ID NO: 80) and a sequence consisting of EVQSYPSKHDYV (SEQ ID NO: 81). WO2013 / 174509 discloses a combination of an agent that stabilizes γδ T cells and an anti-CLDN18.2 antibody, and a combination of an agent that stabilizes or enhances the expression of CLDN18.2 and an anti-CLDN18.2 antibody. These anti-CLDN18.2 antibodies may be conjugated to a moiety that has a therapeutic effect, such as a cytotoxin, a drug (e.g., an immunosuppressant), or a radioisotope. WO2014 / 075788 discloses a method for treating cancer diseases using a bispecific antibody that binds to both CLDN18.2 and CD3. WO2014 / 127906 discloses the combination of multiple agents to stabilize or enhance the expression of CLDN18.2.WO2016 / 166122 discloses anti-CLDN18.2 monoclonal antibodies that can be internalized very efficiently when bound to CLDN18.2, and these characteristics make them suitable for the development of antibody-drug conjugates (ADCs). In addition, this patent also discloses the use of cleavable SPDB linkers or valine-citrulline linkers to link such antibodies to the drugs DM4 or MMAE. However, despite the various antibodies disclosed by these patent applications, the only one currently undergoing clinical trials is the chimeric antibody IMAB362 disclosed in WO2007 / 059997 and WO2016 / 165762. In addition to the aforementioned antibodies and antibody-drug conjugates, WO2018 / 006882 discloses chimeric antigen receptors (CARs) made from anti-CLDN18.2 monoclonal antibodies. In WO2018 / 006882, various antibodies have been humanized, and the sequences of these humanized antibodies are disclosed in the supplementary materials of the collaborative research paper by Jiang et al. (2018). CAR T cells utilizing humanized antibodies are currently undergoing phase I clinical trials in patients with advanced gastric and pancreatic adenocarcinoma (ClinicalTrials.gov ID number: NCT03159819). In CN109762067, another anti-CLDN18.2 monoclonal antibody is disclosed that exerts cytotoxicity via CDC or ADCC. In WO2019 / 173420, an anti-CLDN18.2 humanized monoclonal antibody with ADCC activity is disclosed. In WO2019 / 175617, an anti-CLDN18.2 monoclonal antibody that binds to a different epitope than IMAB362 is disclosed. WO2019 / 219089 discloses a monoclonal antibody that binds to a mutant of CLDN18.2.

[0004] Chimeric antibodies with mouse variable regions grafted onto human constant domains are often immunogenic, which may lead to increased antibody clearance and other safety issues (Sauerborn, 2014). Therefore, antibody sequences need to be further modified to reduce immune responses in patients and enhance the therapeutic activity of the antibody. Humanization is a method of recombining heterologous antibody sequences to reduce their immunogenicity (Saldanha, 2014). However, humanization of antibodies often reduces their affinity. Currently, IMAB362, the most clinically applied anti-CLDN18.2 antibody, is a chimeric antibody. Therefore, there is still a need for further improved anti-CLDN18.2 antibodies. The present invention surprisingly discloses a humanized IMAB362 antibody that has a higher affinity for CLDN18.2 than IMAB362, thereby addressing the above-mentioned problems and other needs. Summary of the Invention

[0005] Definition of Terms An "antibody", also called an "immunoglobulin (Ig)", is a multimeric protein that typically contains four polypeptide chains, two heavy (H) and two light (L) chains. An "antibody" may also include immunoglobulin homologs, which are equivalent to immunoglobulins (e.g., camelid antibodies, which contain only heavy chains, and single domain antibodies (sdAbs) or nanobodies derived from heavy or light chains). An "antibody" also includes antibody-based binding proteins and recombinant antibody formats that retain the ability to bind to a target. An "antibody" also includes functional full-length mutants or variants or derivatives thereof that retain the epitope binding properties of the immunoglobulin molecule required for antibodies, including, but not limited to, murine, chimeric, humanized and fully human antibodies, including bispecific, bispecific, multispecific and bispecific variable domain immunoglobulins. The immunoglobulin molecules may be of any class (e.g., IgG, IgE, IgM, IgD, IgA, and IgY), any subclass (e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2), and any allotype. Immunoglobulin molecules may be mutated to improve or decrease affinity for, for example, Fcγ receptors or fetal Fc receptors (FcRn).

[0006] As used herein, the term "antibody fragment" refers to a molecule that contains at least one polypeptide chain derived from an antibody, which molecule exhibits target binding ability but is not a full-length antibody. Specific examples of antibody fragments include: (i) Fab fragments (monovalent fragments consisting of a light chain variable domain (VL), a heavy chain variable domain (VH), a light chain constant domain (CL) and a heavy chain constant domain 1 (CH1)); (ii) F(ab') 2 Fragment (a bivalent fragment containing two Fab fragments linked by a disulfide bridge in the hinge region (F(ab') 2(iii) the heavy chain portion of the Fab (Fa) fragment (consisting of the VH and CH1 domains); (iv) the variable fragment (Fv) (consisting of the VL and VH domains of one arm of the antibody); (v) the domain antibody (dAb) fragment (containing one variable domain); (vi) isolated complementarity determining regions (CDRs); (vii) single chain Fv fragments (scFv); (viii) diabodies (bivalent, bispecific antibodies in which the VH and VL domains are expressed on a single polypeptide chain, with the VH and VL domains separated by a very short linker). (ix) linear antibodies (a pair of antigen-binding regions formed by the pairing of linearly linked Fv segments (VH-CH1-VH-CH1) with complementary light chain polypeptides); (x) immunoglobulins containing dual variable domains; and (xi) other fragments or portions of immunoglobulin heavy and / or light chains, or mutants, variants or derivatives thereof, used alone or in combination.

[0007] As used herein, an "antibody-based binding protein" may refer to any protein that contains at least one VH, VL, or CH immunoglobulin domain derived from an antibody in a component other than an immunoglobulin or a component not derived from an antibody. Such antibody-based proteins include (i) fusion proteins of a binding protein with an Fc portion (e.g., a receptor that contains all or a portion of the CH domains constituting an immunoglobulin) or receptor component), (ii) VH domain and / orThese include, but are not limited to, binding proteins in which a VL domain is attached to another molecular scaffold, or (iii) molecules that combine immunoglobulin VH, VL and / or CH domains and / or molecules constructed from these domains in a manner not normally found in naturally occurring antibodies or antibody fragments.

[0008] As used herein, "recombinant antibody formats" encompass polyalkylene oxide modified scFvs, monobodies, diabodies, camelid antibodies, domain antibodies, bi- or tri-specific antibodies, IgA structures or structures consisting of two IgGs linked by a J chain and secretory component, shark antibodies, antibodies consisting of framework regions from a New World primate and CDRs from Old World primates, IgG4 antibodies with the hinge region removed, IgGs incorporating two additional binding sites in the CH3 domain, antibodies with modified Fc regions to improve or decrease affinity for Fcγ receptors, dimerization constructs comprising CH3, VL and VH, etc.

[0009] The Kabat numbering scheme (Martin and Allemn, 2014) has been applied to the antibodies disclosed herein.

[0010] As used herein, "selectively binds to CLDN18.2" or "selective binding to CLDN18.2" refers to an antibody that exhibits binding affinity to CLDN18.2 but does not exhibit (specific) binding affinity to CLDN18.1. Thus, an antibody that selectively binds to CLDN18.2 does not exhibit cross-reactivity to CLDN18.1.

[0011] In the detailed description and claims of the present invention, when the term "comprising" is used, it does not exclude other elements. For the purposes of the present invention, an aspect described using the term "consisting of" is considered to be a preferred embodiment of the aspect described using the term "comprising". In the following, when a particular group is defined to include at least a certain number of embodiments, it is understood that a group preferably consisting of only these embodiments is also disclosed.

[0012] Where an indefinite or definite article is used for a singular noun, for example "a", "an" or "the", the plural of that singular noun is also included unless specifically stated otherwise.

[0013] Technical terms are used in their ordinary sense. If a particular term denotes a particular meaning, the definition of that term is set forth below in the context in which the term is used. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] The present inventors have surprisingly identified novel anti-CLDN18.2 antibodies, detailed in the following embodiments, which bind to CLDN18.2 with higher affinity than the IMAB362 antibody.

[0015] Thus, in one embodiment, the present invention provides an antibody or fragment thereof that binds to CLDN18.2, characterized in that the antibody or fragment thereof comprises, as heavy chain complementarity determining regions (HCDRs), the HCDR1 consensus sequence of SEQ ID NO: 1, the HCDR2 consensus sequence of SEQ ID NO: 2, and the HCDR3 consensus sequence of SEQ ID NO: 3, and the light chain complementarity determining regions (LCDRs), the LCDR1 consensus sequence of SEQ ID NO: 4, the LCDR2 consensus sequence of SEQ ID NO: 5, and the LCDR3 consensus sequence of SEQ ID NO: 6. The consensus sequences of each CDR are shown in Table 1. The present invention encompasses any antibody or fragment thereof that is based on any combination of CDRs derived from these consensus sequences and that binds to CLDN18.2.

[0016] In a preferred embodiment, the isolated antibody or functional fragment thereof of the present invention binds to CLDN18.2 but not to CLDN18.1. Thus, the antibody provided by the present invention specifically binds to CLDN18.2. [Table 1]

[0017] The binding or binding affinity of an antibody is usually measured using the equilibrium binding constant (K a ) or the equilibrium dissociation constant (K d ) is the equilibrium binding constant (K a ) is the binding rate constant (k on ) and dissociation rate constant (k off ) and the equilibrium dissociation constant (K d ) is its reciprocal. Thus, the same affinity may be expressed in terms of different rate constants, as long as the ratio of the rate constants does not change. Binding affinity and / or rate constants can be measured using techniques known in the art or methods described herein, including ELISA, flow cytometry (FC) titration, isothermal titration calorimetry (ITC), Biacore (SPR), biolayer interferometry, fluorescence polarization, and the like. Depending on the characteristics of the antigen, the K a Value or K d In some cases, the K value is difficult to measure. This is especially true for integral membrane proteins such as claudins (Hashimoto et al., 2018). In such cases, the integral membrane protein may be expressed as a proteoliposome or lipoparticle. Such lipoparticles may also be immobilized on plastic and used in ELISA assays to measure the binding affinity of an antibody to an immobilized antigen. a Value or K dAlternatively, the binding affinity to the antigen may be determined by calculating the half effective concentration (EC50) value of each test antibody or functional fragment thereof. In Example 3 and FIG. 2 described below, an example of a binding affinity curve by ELISA assay of an antibody having a CDR containing the consensus sequence shown in Table 1 is shown. Thus, binding can be measured as in Example 4, in which the EC50 value (Table 4 in Example 4) and the upper limit of the binding affinity curve (FIG. 4) are used to quantify the binding. Surprisingly, the EC50 value and the upper limit of the binding affinity curve (maximum MFI value) show that the humanized antibody of the present invention has a high binding affinity, i.e., the binding to CLDN18.2 is enhanced compared to the IMAB362 antibody. The maximum value of the mean fluorescence intensity (maximum MFI value) can also be used to quantify the binding of the antibody. When comparing two antibodies that bind to the same target, the higher the maximum MFI value, the higher the affinity and / or the less likely to dissociate. The maximum MFI value can be measured as in Example 4. Table 4 shows the maximum MFI values ​​of the antibodies of the present invention determined by measuring binding to CLDN18.2-expressing HEK293T cells or PA-TU-8988S-High cells by flow cytometry.

[0018] Therefore, the antibody or fragment thereof of the present invention preferably binds to CLDN18.2 with higher affinity than the IMAB362 antibody. Reflecting this, FIG. 1D shows that none of the tested antibodies bind to HEK293T cells expressing CLDN18.1, but selectively bind to CLDN18.2. Furthermore, in a preferred embodiment, such an antibody or fragment thereof is humanized.

[0019] In another embodiment, the present invention provides an antibody or fragment thereof that binds to CLDN18.2, a. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:9 and the HCDR3 sequence of SEQ ID NO:18, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:29; b. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:10 and the HCDR3 sequence of SEQ ID NO:19, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:29; c. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:10 and the HCDR3 sequence of SEQ ID NO:20, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:30; d. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:12 and the HCDR3 sequence of SEQ ID NO:21, and the LCDR1 sequence of SEQ ID NO:26, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:30; e. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:13 and the HCDR3 sequence of SEQ ID NO:18, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:31; f. the HCDR1 sequence of SEQ ID NO:8, the HCDR2 sequence of SEQ ID NO:14, and the HCDR3 sequence of SEQ ID NO:22, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5, and the LCDR3 sequence of SEQ ID NO:29; g. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:15, and the HCDR3 sequence of SEQ ID NO:23, and the LCDR1 sequence of SEQ ID NO:27, the LCDR2 sequence of SEQ ID NO:5, and the LCDR3 sequence of SEQ ID NO:29; h. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:16 and the HCDR3 sequence of SEQ ID NO:23, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:29; or i. the HCDR1 sequence of SEQ ID NO:8, the HCDR2 sequence of SEQ ID NO:17, and the HCDR3 sequence of SEQ ID NO:24, and the LCDR1 sequence of SEQ ID NO:28, the LCDR2 sequence of SEQ ID NO:5, and the LCDR3 sequence of SEQ ID NO:31 The present invention provides an antibody or fragment thereof comprising:

[0020] In a preferred embodiment, the antibody is humanized. As mentioned above, these novel humanized antibodies bind to CLDN18.2 with higher affinity than the IMAB362 antibody, for example, as shown by EC50 and maximum MFI values. Moreover, these antibodies provided by the present invention selectively bind to CLDN18.2.

[0021] In yet another embodiment, the present invention provides an antibody or fragment thereof that binds to CLDN18.2, a. The VH sequence of SEQ ID NO:32; b. The VH sequence of SEQ ID NO:34; c. The VH sequence of SEQ ID NO:35; d. The VH sequence of SEQ ID NO:37; e. The VH sequence of SEQ ID NO:39; f. The VH sequence of SEQ ID NO:41; g. The VH sequence of SEQ ID NO:42; h. the VH sequence of SEQ ID NO: 44; or i. A VH sequence of SEQ ID NO: 45, j. the VL sequence of SEQ ID NO:33; k. The VL sequence of SEQ ID NO:36; l. VL sequence of SEQ ID NO:38; m. VL sequence of SEQ ID NO:40; n. The VL sequence of SEQ ID NO: 43; or o. VL sequence of SEQ ID NO:46 and

[0022] In a preferred embodiment, the antibody is humanized. As mentioned above, these novel humanized antibodies bind to CLDN18.2 with higher affinity than the IMAB362 antibody, for example, as shown by EC50 and maximum MFI values. Moreover, these antibodies provided by the present invention selectively bind to CLDN18.2. The present invention encompasses any isolated antibody or fragment thereof based on any combination of VH and VL regions and binding to CLDN18.2. In a preferred embodiment, the antibody or functional fragment thereof binds to CLDN18.2 but not to CLDN18.1.

[0023] In another embodiment, the present invention provides an antibody or fragment thereof that binds to CLDN18.2, a. The VH sequence of SEQ ID NO: 32 and the VL sequence of SEQ ID NO: 33; b. The VH sequence of SEQ ID NO:34 and the VL sequence of SEQ ID NO:33; c. A VH sequence of SEQ ID NO:35 and a VL sequence of SEQ ID NO:36; d. The VH sequence of SEQ ID NO:37 and the VL sequence of SEQ ID NO:38; e. a VH sequence of SEQ ID NO:39 and a VL sequence of SEQ ID NO:40; f. the VH sequence of SEQ ID NO:41 and the VL sequence of SEQ ID NO:33; g. The VH sequence of SEQ ID NO: 42 and the VL sequence of SEQ ID NO: 43; h. the VH sequence of SEQ ID NO: 44 and the VL sequence of SEQ ID NO: 33; or i. The VH sequence of SEQ ID NO: 45 and the VL sequence of SEQ ID NO: 46 The present invention relates to an antibody or a fragment thereof comprising:

[0024] In a preferred embodiment, the antibody is humanized. Again, as described above, these novel humanized antibodies bind to CLDN18.2 with higher affinity than the IMAB362 antibody, e.g., as shown by EC50 and maximum MFI values. Moreover, these antibodies provided by the present invention selectively bind to CLDN18.2.

[0025] In yet another embodiment, the present invention provides an antibody or fragment thereof that binds to CLDN18.2, a. A heavy chain sequence of SEQ ID NO:49 and a light chain sequence of SEQ ID NO:50; b. A heavy chain sequence of SEQ ID NO:51 and a light chain sequence of SEQ ID NO:50; c. a heavy chain sequence of SEQ ID NO:52 and a light chain sequence of SEQ ID NO:53; d. The heavy chain sequence of SEQ ID NO:54 and the light chain sequence of SEQ ID NO:55; e. a heavy chain sequence of SEQ ID NO:56 and a light chain sequence of SEQ ID NO:57; f. a heavy chain sequence of SEQ ID NO:58 and a light chain sequence of SEQ ID NO:50; g. A heavy chain sequence of SEQ ID NO:59 and a light chain sequence of SEQ ID NO:60; h. a heavy chain sequence of SEQ ID NO:61 and a light chain sequence of SEQ ID NO:50; or i. The heavy chain sequence of SEQ ID NO:62 and the light chain sequence of SEQ ID NO:63 The present invention provides an antibody or fragment thereof comprising:

[0026] In a preferred embodiment, the antibody is humanized. Again, as described above, these novel humanized antibodies bind to CLDN18.2 with higher affinity than the IMAB362 antibody, e.g., as shown by EC50 and maximum MFI values. Moreover, these antibodies provided by the present invention selectively bind to CLDN18.2.

[0027] In another embodiment, the present invention provides a humanized antibody or fragment thereof that binds to CLDN18.2. Humanization of monoclonal antibodies is already well established. The Handbook of Therapeutic Antibodies, Second Edition, provides ample information on humanizing monoclonal antibodies (Saldanha, 2014), bioinformatics tools for analyzing such antibodies (Martin and Allemn, 2014), or developing and producing therapeutic antibodies (Jacobi et al., 2014). When used as a human therapeutic agent, humanized antibodies have a lower risk of inducing anti-drug antibodies than chimeric antibodies. Anti-drug antibodies may limit the therapeutic benefit and may increase the risk of side effects of the antibodies of the present invention, especially with repeated administration.

[0028] In another embodiment, the present invention provides an isolated antibody or functional fragment thereof that binds to CLDN18.2.

[0029] In one embodiment, the antibody of the present invention does not bind to CLDN18.1, and therefore does not exhibit cross-reactivity.

[0030] In another embodiment, the present invention provides an antibody or functional fragment thereof that binds to CLDN18.2, the antibody or functional fragment thereof consisting of a heavy chain sequence of SEQ ID NO:58 and a light chain sequence of SEQ ID NO:50.

[0031] In yet another embodiment, the invention relates to an antibody having an amino acid sequence having at least 80% identity, at least 85% identity, at least 90% identity, at least 95% identity or at least 98% identity with the amino acid sequence of an antibody described herein. The antibody preferably binds to CLDN18.2 with higher affinity and / or selectively to CLDN18.2 than the IMAB362 antibody, e.g., as indicated by EC50 and maximum MFI values. In one embodiment, the antibody is humanized.

[0032] In one embodiment, the present invention provides an antibody or fragment thereof that binds to CLDN18.2 and competitively binds with an antibody or fragment thereof described herein. In a preferred embodiment, the antibody or fragment thereof competitively binds with an antibody consisting of the heavy chain sequence of SEQ ID NO: 58 and the light chain sequence of SEQ ID NO: 50. In one embodiment, the antibody is humanized. In a further preferred embodiment, the antibody exhibits a binding affinity comparable to or higher than that of IMAB362. In another preferred embodiment, the antibody exhibits a binding affinity comparable to or higher than that of an antibody consisting of the heavy chain sequence of SEQ ID NO: 58 and the light chain sequence of SEQ ID NO: 50. The binding affinity may be measured by any suitable means. For example, the EC50 value or the maximum MFI value of flow cytometric titration may be measured in HEK295T cells or PA-TU-8988-High cells expressing CLDN18.2 as an index for evaluating the binding of the antibody.

[0033] In another embodiment, the Fc domain of the antibody (or antibody fragment, if present) may comprise modifications or mutations, such as those listed in Table 2 below. Such modifications or mutations may be introduced to modulate the effector activity of the Fc domain of the antibody. Antibody modifications may further include peptide tags added to the C-terminus of the antibody heavy and / or light chains. Such tags may be used, for example, for protein purification or protein conjugation.

[0034] In another embodiment, the present invention is directed to IgA1, IgA2, IgD, IgE, IgG1, IgG2, IgG3, IgG4, synthetic IgG, IgM, F(ab) 2 , Fv, scFv, IgGACH2, F(ab') 2 , scFvCH3, Fab, VL, VH, scFv4, scFv3, scFv2, dsFv, Fv, scFv-Fc, (scFv) 2 The present invention provides an isolated humanized antibody or fragment thereof that binds to CLDN18.2 in a format selected from a non-depleting IgG, a diabody and a bivalent antibody, and Fc recombinant versions thereof.

[0035] In a preferred embodiment, the antibody of the present invention is an IgG1 antibody. The Fc region of an immunoglobulin interacts with various types of Fcγ receptors (FcγR) and complement proteins (e.g., C1q) and is responsible for the effector functions of the immune system (such as the elimination of target cells) through antibody-dependent cellular cytotoxicity (ADCC), antibody-dependent cellular phagocytosis (ADCP) or complement-dependent cytotoxicity (CDC). Enhancing or suppressing the effector functions associated with the Fc region may be beneficial for therapeutic applications. The type of immunoglobulin (IgA, IgD, IgE, IgG, IgM) may be selected depending on the desired effector functions of the antibody associated with the Fc domain, taking into account these known activities. Synthetic immunoglobulins may also be used, such as immunoglobulins containing amino acid residues 118-260 of IgG2 and amino acid residues 261-447 of IgG4, or IgG2 variants into which point mutations derived from IgG4 (e.g., H268Q / V309L / A30S / P331S) have been introduced. Such synthetic immunoglobulins have reduced antibody effector functions. In addition, immunoglobulins with recombinant Fc regions may also be used to regulate antibody effector functions. An example of such genetic recombination of Fc regions is shown in Table 2. Furthermore, in order to regulate the pharmacokinetics of antibodies, binding to Fcγ receptors may be influenced by expressing fucosylated sugar chains from recombinant protein-producing cell lines. [Table 2]

[0036] The half-life of an antibody in vivo may be adjusted. The Fc domain plays a central role in the stability and serum half-life of an antibody. In therapeutic applications, the half-life of an antibody may be shortened by using antibody fragments with the Fc domain removed or partially truncated, such as F(ab) . 2 , Fv, scFv, IgGACH2, F(ab') 2 , scFvCH3, Fab, VL, VH, scFv4, scFv3, scFv2, dsFv, Fv, scFv-Fc, (scFv)2 and the like. The antibody of the present invention may be in the form of a diabody or bivalent antibody. The use of a diabody or bivalent antibody may increase the affinity to the target and reduce the dose. Functional fragments with the Fc domain removed or partially truncated may be used to develop alternative therapeutic methods, such as chimeric antigen receptor T cells (CAR T cells) and bispecific T cell-inducing antibodies (BiTEs). In a CAR construct, one VH domain and one VL domain are usually linked via a short peptide linker to form a single chain variable fragment (scFv), which is further linked to a transmembrane domain and a cytoplasmic T cell immunoreceptor activation tyrosine motif (e.g., activation tyrosine motif from CD3ζ), which is further linked to a costimulatory molecule domain (e.g., costimulatory molecule domain from CD28, 4-1BB (CD127) or OX40) (Chang and Chen, 2017). The VH and VL domains used in this scFv fragment may be any of the antibodies listed in Table 3. BiTEs are usually composed of two domains derived from two different antibodies. of The CLDN18.2-binding scFv is fused to the CLDN18.2-binding scFv domain, where one scFv domain may be derived from any of the isolated antibodies that bind to CLDN18.2 listed in Table 3, and the other scFv domain may be derived from an antibody that binds, for example, CD3, CD16, NKG2D, NKp46, CD2, CD28, or CD25. For detailed guidelines on the BiTE antibody format and other bispecific antibody formats used to confer targeting to T cells, the reader may refer to the review article by Diego Ellerman (2019).

[0037] In another embodiment, the present invention provides a humanized antibody or fragment thereof that binds to CLDN18.2, characterized in that the humanized antibody or fragment thereof has a light chain constant region (CL) of SEQ ID NO: 65, and preferably further has a CH1 domain and Fc region of a heavy chain constant region of SEQ ID NO: 66, which have L234A / L235A mutations in the CH2 domain of the heavy chain constant region and thus have reduced FcγR binding. More preferably, the present invention provides an antibody having a CH1 domain and Fc region of a heavy chain constant region of SEQ ID NO: 67, which have L234A / L235A / P329G mutations in the CH1 domain and Fc region of the heavy chain constant region and thus have further reduced FcγR binding.

[0038] In another embodiment, the present invention provides an isolated humanized antibody or fragment thereof that binds to CLDN18.2, the humanized antibody or fragment thereof comprising a heavy chain variable region (VH) sequence of SEQ ID NO: 41 linked to a CH1 domain and Fc region of a heavy chain constant region of SEQ ID NO: 66, and a light chain variable region (VL) sequence of SEQ ID NO: 33 linked to a light chain constant region (CL) of SEQ ID NO: 65.

[0039] In yet another embodiment, the present invention provides an antibody or fragment thereof that does not bind to CLDN18.1 but binds to CLDN18.2. Thus, the antibody does not show cross-reactivity or cross-binding to CLDN18.1. The binding of the antibody to the target protein can be tested by performing flow cytometry on cells expressing the target protein. The specific binding of the tested antibody to the target protein can be visualized in a histogram plot. If the tested antibody specifically binds to the expressed target protein, a high fluorescent signal peak is observed in the histogram plot, and if the tested antibody does not bind or can only bind very weakly to the expressed target protein, a low fluorescent signal peak is observed in the histogram plot. Such a histogram is shown in FIG. 1. The histogram in FIG. 1 shows that the antibody of the present invention does not bind to CLDN18.1 expressed in HEK293T cells, but binds to CLDN18.2. The degree of binding can also be shown as a bar graph depicting the maximum mean fluorescence intensity (max MFI value) as measured by flow cytometry, with a high max MFI value indicating strong binding and a low or no max MFI value indicating no binding. An example of such a binding assay is shown in Example 4.

[0040] In another embodiment, the present invention provides an antibody or fragment thereof that binds to CLDN18.2, the antibody or fragment thereof being conjugated to another moiety, such as a radioisotope, a fluorescent tag, a histological marker, a cytotoxin, or a cytokine. The other moiety may be conjugated via a linker known in the art.

[0041] In yet another embodiment, the present invention provides an antibody or fragment thereof that binds to CLDN18.2, the antibody or fragment thereof being more potent than the IMAB362 antibody. Preferably, the present invention provides an antibody or fragment thereof that binds to CLDN18.2, the antibody or fragment thereof being more avid than the IMAB362 antibody. The binding affinity and / or rate constant can be measured using techniques known in the art or methods described herein, including ELISA, flow cytometric titration, isothermal titration calorimetry (ITC), Biacore (SPR), biolayer interferometry, fluorescence polarization, and the like. The present inventors measured the affinity of the antibody to CLDN18.2, for example, by ELISA as shown in Example 3 and flow cytometric titration experiments as shown in Example 4. ELISA performed on lipoparticles containing CLDN18.2 showed that the humanized antibodies hGBA-1 to hGBA-9 all had higher maximum binding values ​​(indicated by MFI) than IMAB362. In flow cytometry titration experiments using HEK293T cells overexpressing CLDN18.2 or PA-TU-8988S cells endogenously expressing CLDN18.2, the humanized antibodies hGBA-1 to hGBA-9 all had higher maximum binding values ​​(expressed in MFI units) and lower EC50 values ​​(expressed in μg / ml) than the IMAB362 antibody, indicating that the humanized antibodies of the present invention have a higher affinity for CLDN18.2 than the IMAB362 antibody. In one embodiment, the antibodies provided by the present invention have a measured EC50 value that is at least 10%, at least 20%, at least 40%, at least 50%, or at least 75% lower than the EC50 value of the IMAB362 antibody. In one embodiment, the antibodies provided by the invention have a maximum measured MFI value that is at least 10%, at least 20%, at least 40%, at least 50%, or at least 75% higher than the maximum MFI value of the IMAB362 antibody.

[0042] The heavy and light chain sequences of the IMAB362 antibody are provided herein, for example, as SEQ ID NO:47 and SEQ ID NO:48, respectively.

[0043] According to one embodiment, the present invention provides a nucleic acid sequence encoding an antibody or fragment thereof that binds to CLDN18.2. The nucleic acid sequence may encode only the CDRs of the antibody, may encode the variable heavy (VH) and variable light (VL) regions of the antibody, or may encode the full-length heavy and light chains of the antibody. Such nucleic acid sequences are shown in Table 3. The nucleic acid sequences include F(ab) 2 , Fv, scFv, IgGACH2, F(ab') 2 , scFvCH3, Fab, VL, VH, scFv4, scFv3, scFv2, dsFv, Fv, scFv-Fc, (scFv) 2 The nucleic acid sequence may encode an antibody that is capable of binding to a target IgG, a non-depleting IgG (IgG that does not induce cell loss), a diabody, a bivalent antibody, or an Fc recombinant thereof. The immunoglobulin encoded by the nucleic acid sequence may be IgA1, IgA2, IgD, IgE, IgG1, IdG2, IgG3, IgG4, a synthetic IgG, IgM, or a mutant or Fc recombinant thereof.

[0044] In yet another embodiment, the present invention provides an antibody-based binding protein that binds to CLDN18.2, e.g., a protein comprising at least the CLDN18.2-binding domain of an antibody disclosed herein and another protein domain unrelated to the antibody. Additionally, the present invention provides a recombinant humanized antibody format that binds to CLDN18.2. In a preferred embodiment, the antibody-based binding protein does not bind to CLDN18.1.

[0045] In another embodiment, the present invention provides a nucleic acid encoding said antibody or a fragment thereof. The nucleic acid sequence may encode other components or may encode a portion of a chimeric antigen receptor (CAR) that binds CLDN18.2. Detailed guidance on the construction of CAR T cells is provided in Chang and Chen (2017) or June and Sadelain (2018). In one embodiment, the present invention provides a T cell genetically engineered to produce an artificial T cell receptor, the artificial T cell receptor being an antibody or a functional fragment thereof of the present invention that binds CLDN18.2. of In one preferred embodiment, the CAR construct does not bind to CLDN18.1.

[0046] The present invention further provides an expression vector comprising said nucleic acid. The expression vector may be an expression vector intended for expression in mammalian cells, bacterial cells, fungal cells or insect cells, and may be selected depending on the type of host cell into which said expression vector comprising a nucleic acid encoding said antibody or a functional fragment thereof is to be introduced. Detailed guidance on the construction of such vectors is given in the book by Green and Sambrook (Green and Sambrook, 2012). Expression vectors for mammalian cells are preferred, and expression vectors for CHO cells are particularly preferred.

[0047] In another embodiment, the present invention provides a host cell comprising an expression vector encoding an antibody or fragment thereof that binds to CLDN18.2, or a host cell in which a nucleic acid encoding an antibody or fragment thereof that binds to CLDN18.2 is integrated into the genome. The host cell may be a mammalian cell or a mammalian cell line, a bacterial cell, a fungal cell, or an insect cell. Mammalian cells are preferred, and CHO cells are particularly preferred.

[0048] In another embodiment, the present invention relates to an antibody or fragment thereof that binds CLDN18.2, a nucleic acid encoding said antibody or fragment thereof, a vector comprising said nucleic acid, a host cell comprising said nucleic acid, or a vector comprising said nucleic acid, as described herein, for use in treating a subject suffering from, at risk of developing, and / or diagnosed with a neoplastic disease. The antibody or fragment thereof disclosed herein may be used as a monotherapy, but is preferably used as a combination therapy in combination with an established standard of care for the neoplastic disease.

[0049] In yet another embodiment, the present invention provides the use of an antibody or fragment thereof of the present invention that binds to CLDN18.2 for the manufacture of a medicament for the treatment of a neoplastic disease.

[0050] The neoplastic disease may be at least one selected from the group consisting of pancreatic cancer, gastric cancer, esophageal cancer, ovarian cancer and lung cancer. The neoplastic disease to be treated is characterized by overexpression of CLDN18.2.

[0051] Another embodiment of the present invention provides a method of treating neoplastic diseases such as pancreatic cancer, gastric cancer, esophageal cancer, ovarian cancer, lung cancer, etc., using an isolated humanized antibody or fragment thereof of the present invention that binds to CLDN18.2, comprising administering a therapeutically effective amount of said antibody or fragment thereof. The method of treatment may be a monotherapy, but is preferably a combination therapy in combination with an established standard treatment for the neoplastic disease.

[0052] Further provided is a pharmaceutical composition comprising the antibody or fragment thereof that binds to CLDN18.2, a nucleic acid encoding the antibody or fragment thereof, a vector comprising the nucleic acid, a host cell comprising the nucleic acid, or a vector comprising the nucleic acid, and a pharma- ceutically acceptable carrier.

[0053] Preferably, the isolated humanized antibody or fragment thereof of the present invention that binds to CLDN18.2 may be used to treat patients suffering from pancreatic cancer, gastric cancer, esophageal cancer, ovarian cancer or lung cancer. [Brief description of the drawings]

[0054] [Figure 1] FACS binding assay of humanized antibodies and IMAB362 is shown. Binding of selected antibodies to huCLDN18.2 or huCLDN18.1 was tested in HEK293T cells stably expressing huCLDN18.2 or huCLDN18.1. Parental HEK293T cells not expressing these target proteins (huCLDN18.2 and huCLDN18.1) were used as negative control. (Figure 1A) A: IMAB362, B: hGBA-1, C: hGBA-2, D: hGBA-3, E: hGBA-4, F: hGBA-5, G: hGBA-6, H: hGBA-7, I: hGBA-8, J: GBA-9, K: secondary antibody only, L: pan-CLDN18 antibody are shown. (FIG. 1B) Bar graph showing the mean fluorescence intensity (MFI) of FACS data comparing binding of each humanized antibody to IMAB362 in HEK293T cells expressing huCLDN18.2 or huCLDN18.1 or parental HEK293T cells. [Diagram 2] (FIGS. 2A to 2D) The results of comparing the humanized antibody and IMAB362 by ELISA binding assay are shown. The ELISA binding assay was performed using lipoparticles containing CLDN18.2 or null lipoparticles not containing CLDN18.2. [Diagram 3] Sorting of PA-TU-8988S cells based on the expression level of CLDN18.2. (FIG. 3A) FACS profile of PA-TU-9888S cells stained with IMAB362. (FIG. 3B) FACS profile of PA-TU-8988S cells sorted by FACS based on high and moderate expression of CLDN18.2. [Figure 4]Flow cytometric titration assays in PA-TU-8988S-High cells (Figure 4A-D) and HEK-293T cells expressing huCLDN18.2 (Figure 4E-H) are shown. EXAMPLES

[0055] Example 1: Humanization of Fab fragments The technology of humanizing monoclonal antibodies is already well established. The Handbook of Therapeutic Antibodies, Second Edition provides ample information on humanizing monoclonal antibodies (Saldanha, 2014), bioinformatics tools to analyze such antibodies (Martin and Allemn, 2014), or developing and producing therapeutic antibodies (Jacobi et al., 2014). Briefly, the variable domain sequences of the IMAB362 parent antibody were analyzed to find the human germline expressing protein that most closely matches the target of this antibody. Then, a structural analysis of the variable regions of the IMAB362 parent antibody was performed to find the best-fitting Fv model, and a structural analysis of CDR grafting was performed by in silico modeling. Based on this in silico modeling, humanized VH and VL domains were designed. Various combinations of humanized VH and VL domains were cloned and these VH and VL domain combinations were produced as Fab antibodies or IgG1 antibodies, and were analyzed by ELISA and AlphaLISA. TMThese antibodies were screened by analyzing the binding of the antibodies to lipoparticles expressing CLDN18.2 using ELISA and by analyzing the binding of the antibodies by flow cytometry using the pre-B cell line L11 (Waldmeier et al., 2016) or HEK293T cell line (ATCC CRL-3216) expressing CLDN18.1 or CLDN18.2. By performing these tests and comparing the results with the IMAB362 parent antibody, a set of VH and VL domain combinations was selected and a library in scFv format was designed to further humanize the CDRs, etc. ELISA and AlphaLISA using lipoparticles expressing CLDN18.2 TM The scFv library thus prepared was further screened by performing flow cytometry using a pre-B cell line L11 expressing CLDN18.1 or CLDN18.2. In this manner, IMAB362 was humanized to obtain humanized antibodies, including hGBA-1 antibody, hGBA-2 antibody, hGBA-3 antibody, hGBA-4 antibody, hGBA-5 antibody, hGBA-6 antibody, hGBA-7 antibody, hGBA-8 antibody, and hGBA-9 antibody (see Table 3). In the present specification, these humanized antibodies are collectively referred to as hGBA antibodies. [Table 3] TIFF0007641967000004.tif254165TIFF0007641967000005.tif254166TIFF000 7641967000006.tif254165TIFF0007641967000007.tif235170TIFF00076419670 00008.tif250170TIFF0007641967000009.tif254166TIFF0007641967000010.t if254166TIFF0007641967000011.tif254166TIFF0007641967000012.tif116170

[0056] The antibodies described in Examples 2-4 below were engineered to contain a RLPXTGG tag (SEQ ID NO: 143) at the C-terminus of the heavy chain and / or a GGGGSLPXTGG tag (SEQ ID NO: 144) at the C-terminus of the light chain, where X is any of the 20 naturally occurring amino acids. In these antibodies, the C-terminal lysine (K) of the heavy chain was replaced with an arginine (R) from this tag. The addition of these tags did not alter the affinity and selectivity of each antibody for CLDN18.2.

[0057] Example 2: FACS binding analysis of humanized monoclonal antibodies The HEK293T cell line (ATCC CRL-3216) does not endogenously express CLDN18.1 or CLDN18.2. Therefore, CLDN18.1 or CLDN18.2 was overexpressed in this HEK293T cell line, and the binding activity of the antibody was tested. Specifically, a transposase expression construct (pcDNA3.1-hy-mPB), a transposon construct containing the full-length huCLDN18.1 (pPB-Puro-huCldn18.1) or a transposon construct containing the full-length huCLDN18.2 (pPB-Puro-huCldn18.2), a puromycin expression cassette, and an EGFP-containing construct (pEGFP-N3) as a transfection control were co-transfected into HEK293T cells by electroporation. After transfection, the cells were incubated at 4°C for 1 h in a humidified incubator at 5% CO 2Cells were allowed to recover for 2 days at 37°C in growth medium under ambient conditions. Transfection was confirmed by analyzing EGFP expression by flow cytometry. Cells expressing huCLDN18.1 or huCLDN18.2 were then selected by adding 1 μg / ml puromycin to the culture, and the selected cells were further expanded to generate frozen stocks in FCS containing 10% DMSO. Expression of huCLDN18.2 in transfected HEK293T cells was analyzed by FACS. Briefly, HEK293T cells were trypsinized and harvested by centrifugation, then resuspended in PBS containing 2% FCS, and stained for huCLDN18.2 with IMAB362 at 2 μg / ml as the primary antibody for 30 min on ice. Cells were washed with PBS containing 2% FCS, and stained with PE-labeled anti-human Fcγ-specific IgG goat antibody (eBioscience) as the secondary antibody for 30 min on ice. Stained cells were washed again, resuspended in ice-cold FACS buffer, and analyzed using a FACSCalibur. TM The cells were analyzed by the instrument (see FIG. 1A). Parental cells, which were not transfected and therefore did not express CLDN18.2, were used as a negative control. Analysis of CLDN18.1 expression was performed in a similar manner using a commercially available pan-CLDN18 antibody that recognizes CLDN18.1 and CLDN18.2. Any pan-CLDN18 antibody for flow cytometry measurement can be used appropriately, and such pan-CLDN18 antibodies include, for example, anti-claudin 18 / CLDN18 (C-terminus) antibody (catalog No. AP50944PUN) commercially available from OriGene Technologies, CLDN18 (C-terminus) rabbit polyclonal antibody (catalog No. MBS8555451) commercially available from MyBioSource, or CLDN18 antibody (catalog No. 63-847) commercially available from ProSci.

[0058] HEK293T cells stably expressing huCLDN18.1 or huCLDN18.2 were finally selected and used to test humanized antibodies hGBA-1, hGBA-2, hGBA-3, hGBA-4, hGBA-5, hGBA-6, hGBA-7, hGBA-8 and hGBA-9 for binding specificity of not binding to huCLDN18.1 but to CLDN18.2. Cells were stained with 2 μg / ml of each antibody for 30 min on ice, washed with FACS buffer (PBS containing 2% FCS) and then stained with PE-labeled anti-human Fcγ-specific IgG goat antibody (eBioscience) as secondary antibody for 30 min on ice. The expression of CLDN18.1 in HEK293T cells stably expressing huCLDN18.1 was confirmed with pan-CLDN18 antibody (see panel L in FIG. 1), and the expression of CLDN18.2 in HEK293T cells stably expressing huCLDN18.2 was confirmed with IMAB362 antibody (see panel A in FIG. 1). FIG. 1 shows that all humanized antibodies specifically bind to huCLDN18.2 expressed in HEK293T cells, but not to huCLDN18.1. Furthermore, these humanized antibodies were shown to bind to huCLDN18.2 more strongly than the parent antibody IMAB362.

[0059] Example 3: Binding analysis of humanized monoclonal antibodies by ELISA Using CLDN18.2-containing lipoparticles as a source of antigen, the binding affinity of humanized antibodies (hGBA) to CLDN18.2 was tested in an ELISA assay. CLDN18.2 lipoparticles or null lipoparticles (as a negative control without antigen) were coated onto 96-well plates to a final concentration of 10 U / ml. Plates were washed with PBS containing 0.05% Tween-20 (PBS-T) and blocked with PBS-T containing 3% BSA for at least 1 h at 37°C. Each hGBA or IMAB362 antibody was serially diluted 1:3 from a starting concentration of 2 μg / ml in PBS-T containing 1% BSA and added to each coated well and incubated at 37°C for at least 1 h. HRP-labeled goat anti-human secondary antibody diluted in PBS-T containing 1% BSA was then bound, followed by development with Sigma-Fast OPD as peroxidase substrate and 2M H 2 SO 4 The reaction was stopped by adding 0.1% HO and the antibody bound to the plate was detected by reading the absorbance at 490 nm using an ELISA plate reader. Representative binding curves are shown in Figure 2. Surprisingly, in the binding curves shown in Figure 2, the maximum binding values ​​of all the humanized antibodies (hGBA-1 to hGBA-9) were higher than that of IMAB362, indicating that these humanized antibodies (hGBA-1 to hGBA-9) bind to CLDN18.2 lipoparticles with higher affinity than IMAB362.

[0060] Example 4: Flow cytometric titration in HEK293T and PA-TU-8988-High cells PA-TU-8988S cells (Creative Bioarray, Cat. No. CSC-C0326) with high expression of CLDN18.2 were selected by FACS. Herein, the selected cells are referred to as PA-TU-8988S-High cells. Specifically, the PA-TU-8988S cell population was stained with IMAB362 antibody and analyzed by FACS, which showed high and moderate expression of CLDN18.2 (see Figure 3A). To obtain a more homogenous cell population, PA-TU-8988S cells were sorted by FACS to select only cells with high expression of CLDN18.2. Briefly, PA-TU-8988S cells were suspended in FACS buffer (PBS containing 2% FCS) and incubated with 2 μg / ml of IMAB362 on ice for 30 min. After washing with FACS buffer, cells were incubated with PE-labeled Fcγ-specific goat IgG anti-human secondary antibody (eBioscience) for 30 min on ice. After washing, stained cells were resuspended in FACS buffer and analyzed by FACSAria. TM By analyzing and sorting with the instrument, cells that moderately express CLDN18.2 (Figure 3B) were removed from cells that highly express CLDN18.2 (Figure 3B). After sorting, the recovered PA-TU-8988S-High cells were resuspended in growth medium, grown in growth medium, and aliquots were frozen and stored in liquid nitrogen.

[0061] To quantify the affinity of each antibody for CLDN18.2, 250 × 10 HEK293T cells or PA-TU-8988-High cells overexpressing CLDN18.2 were cultured in FC buffer (PBS containing 2% FCS) in a 96-well plate. 3 The cells were seeded at a density of 1000 cells / well and centrifuged to pellet. The IMAB362 antibody and each hGBA antibody to be tested were diluted to 4 μg / ml, then serially diluted 1:4, added to the plated cells, and incubated at 4°C for 30 minutes. After washing with FACS buffer, a PE-labeled anti-human IgG antibody was added as a secondary antibody to the cells, incubated at 4°C for another 30 minutes, and washed again with FC buffer. The cells were resuspended in 100 μl of FC buffer and analyzed by FACSCalibur. TMThe binding affinity of each hGBA antibody to CLDN18.2 was measured using a cell analyzer (BD Biosciences, USA). The results of flow cytometry analysis (see FIG. 4 and Table 4) showed that the binding affinity of each hGBA antibody to CLDN18.2 was stronger than that of the IMAB362 antibody in both cell lines (the maximum MFI value of the tested novel antibodies was higher than that of the IMAB362 antibody (see Table 4)). In addition, the binding affinity of each hGBA antibody was shown to be comparable among the hGBA antibodies, but significantly higher than that of the parent antibody IMAB362. [Table 4]

[0062] The present invention will be further described with reference to the following embodiments.

[0063] 1. An antibody or fragment thereof that binds to CLDN18.2, comprising an HCDR1 sequence of SEQ ID NO: 1, an HCDR2 sequence of SEQ ID NO: 2, and an HCDR3 sequence of SEQ ID NO: 3, and an LCDR1 sequence of SEQ ID NO: 4, an LCDR2 sequence of SEQ ID NO: 5, and an LCDR3 sequence of SEQ ID NO: 6.

[0064] 2. a. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:9 and the HCDR3 sequence of SEQ ID NO:18, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:29; b. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:10 and the HCDR3 sequence of SEQ ID NO:19, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:29; c. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:10 and the HCDR3 sequence of SEQ ID NO:20, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:30; d. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:12 and the HCDR3 sequence of SEQ ID NO:21, and the LCDR1 sequence of SEQ ID NO:26, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:30; e. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:13 and the HCDR3 sequence of SEQ ID NO:18, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:31; f. the HCDR1 sequence of SEQ ID NO:8, the HCDR2 sequence of SEQ ID NO:14, and the HCDR3 sequence of SEQ ID NO:22, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5, and the LCDR3 sequence of SEQ ID NO:29; g. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:15, and the HCDR3 sequence of SEQ ID NO:23, and the LCDR1 sequence of SEQ ID NO:27, the LCDR2 sequence of SEQ ID NO:5, and the LCDR3 sequence of SEQ ID NO:29; h. the HCDR1 sequence of SEQ ID NO:7, the HCDR2 sequence of SEQ ID NO:16 and the HCDR3 sequence of SEQ ID NO:23, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5 and the LCDR3 sequence of SEQ ID NO:29; or i. the HCDR1 sequence of SEQ ID NO:8, the HCDR2 sequence of SEQ ID NO:17, and the HCDR3 sequence of SEQ ID NO:24, and the LCDR1 sequence of SEQ ID NO:28, the LCDR2 sequence of SEQ ID NO:5, and the LCDR3 sequence of SEQ ID NO:31 2. The antibody or fragment thereof of embodiment 1, comprising:

[0065] 3. a. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 32; b. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 34; c. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 35; d. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 37; e. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 39; f. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 41; g. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 42; h. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 44; or i. a VH sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 45; j. a VL sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 33; k. a VL sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 36; l. a VL sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 38; m. a VL sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 40; n. a VL sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 43; or o. A VL sequence having at least 80%, at least 85%, at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 46. 3. The antibody or fragment thereof of embodiment 1 and 2, comprising:

[0066] 4. a. The VH sequence of SEQ ID NO:32; b. The VH sequence of SEQ ID NO:34; c. The VH sequence of SEQ ID NO:35; d. The VH sequence of SEQ ID NO:37; e. The VH sequence of SEQ ID NO:39; f. The VH sequence of SEQ ID NO:41; g. The VH sequence of SEQ ID NO:42; h. the VH sequence of SEQ ID NO: 44; or i. A VH sequence of SEQ ID NO: 45, j. the VL sequence of SEQ ID NO:33; k. The VL sequence of SEQ ID NO:36; l. VL sequence of SEQ ID NO:38; m. VL sequence of SEQ ID NO:40; n. The VL sequence of SEQ ID NO: 43; or o. VL sequence of SEQ ID NO:46 The antibody or fragment thereof according to any one of embodiments 1 to 3,

[0067] 5. a. The VH sequence of SEQ ID NO: 32 and the VL sequence of SEQ ID NO: 33; b. The VH sequence of SEQ ID NO:34 and the VL sequence of SEQ ID NO:33; c. A VH sequence of SEQ ID NO:35 and a VL sequence of SEQ ID NO:36; d. The VH sequence of SEQ ID NO:37 and the VL sequence of SEQ ID NO:38; e. a VH sequence of SEQ ID NO:39 and a VL sequence of SEQ ID NO:40; f. the VH sequence of SEQ ID NO:41 and the VL sequence of SEQ ID NO:33; g. The VH sequence of SEQ ID NO: 42 and the VL sequence of SEQ ID NO: 43; h. the VH sequence of SEQ ID NO: 44 and the VL sequence of SEQ ID NO: 33; or i. The VH sequence of SEQ ID NO: 45 and the VL sequence of SEQ ID NO: 46 The antibody or fragment thereof according to any one of embodiments 1 to 4, comprising:

[0068] 6. a. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:49 and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:50; b. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:51 and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:50; c. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:52 and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:53; d. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:54 and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:55; e. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:56 and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:57; f. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:58 and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:50; g. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:59 and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:60; h. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:61 and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:50; or i. a heavy chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:62, and a light chain sequence having at least 80%, at least 85%, at least 90%, at least 95% or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:63. 6. The antibody or fragment thereof according to any one of embodiments 1 to 5, comprising:

[0069] 7. a. A heavy chain sequence of SEQ ID NO:49 and a light chain sequence of SEQ ID NO:50; b. A heavy chain sequence of SEQ ID NO:51 and a light chain sequence of SEQ ID NO:50; c. a heavy chain sequence of SEQ ID NO:52 and a light chain sequence of SEQ ID NO:53; d. The heavy chain sequence of SEQ ID NO:54 and the light chain sequence of SEQ ID NO:55; e. a heavy chain sequence of SEQ ID NO:56 and a light chain sequence of SEQ ID NO:57; f. a heavy chain sequence of SEQ ID NO:58 and a light chain sequence of SEQ ID NO:50; g. A heavy chain sequence of SEQ ID NO:59 and a light chain sequence of SEQ ID NO:60; h. a heavy chain sequence of SEQ ID NO:61 and a light chain sequence of SEQ ID NO:50; or i. The heavy chain sequence of SEQ ID NO:62 and the light chain sequence of SEQ ID NO:63 7. The antibody or fragment thereof according to any one of embodiments 1 to 6, comprising:

[0070] 8. An antibody or a fragment thereof that competitively binds to the antibody or fragment thereof according to any one of embodiments 1 to 7.

[0071] 9. The format of the antibody or fragment thereof is IgA1, IgA2, IgD, IgE, IgG1, IgG2, IgG3, IgG4, synthetic IgG, IgM, F(ab) 2 , Fv, scFv, IgGACH2, F(ab') 2 , scFvCH3, Fab, VL, VH, scFv4, scFv3, scFv2, dsFv, Fv, scFv-Fc, (scFv) 2 The antibody or fragment thereof according to any one of embodiments 1 to 8, which is selected from the group consisting of an antibody, a non-depleting IgG, a diabody and a bivalent antibody, and Fc recombinant antibodies thereof.

[0072] 10. The antibody or fragment thereof according to any one of embodiments 1 to 9, which is a humanized antibody or fragment thereof.

[0073] 11. The antibody or fragment thereof according to any one of embodiments 1 to 10, which is an isolated antibody or fragment thereof.

[0074] 12. An antibody or fragment thereof according to any one of embodiments 1 to 11, which is an antibody or fragment thereof that does not bind to CLDN18.1.

[0075] 13. The antibody or fragment thereof according to any one of embodiments 1 to 12, wherein the binding of the antibody or fragment thereof to CLDN18.2 is enhanced compared to IMAB362.

[0076] 14. The antibody or fragment thereof according to embodiment 13, wherein the EC50 value and / or the maximum MFI value of flow cytometric titration is measured in CLDN18.2-expressing cells as an index for evaluating the enhanced binding, and the CLDN18.2-expressing cells are preferably HEK293T cells or PA-TU-8988-High cells.

[0077] 15. The antibody or fragment thereof of embodiment 14, wherein the measured EC50 value of the antibody is at least 10%, at least 20%, at least 40%, at least 50%, or at least 75% lower than the EC50 value of IMAB362.

[0078] 16. The antibody or fragment thereof of embodiment 14, wherein the maximum MFI value of the antibody measured is at least 10%, at least 20%, at least 40%, at least 50%, or at least 75% higher than the maximum MFI value of IMAB362.

[0079] 17. A nucleic acid encoding an antibody or a fragment thereof according to any one of embodiments 1 to 16.

[0080] 18. A vector comprising the nucleic acid of embodiment 17.

[0081] 19. A host cell comprising a nucleic acid according to embodiment 17 or a vector according to embodiment 18.

[0082] 20. An antibody or fragment thereof described in any one of embodiments 1 to 16, a nucleic acid described in embodiment 17, a vector described in embodiment 18 or a host cell described in embodiment 19 for use in treating a. a subject suffering from a neoplastic disease, b. a subject at risk of developing a neoplastic disease, and / or c. a subject diagnosed with a neoplastic disease.

[0083] 21. The antibody or fragment thereof according to embodiment 20, wherein the neoplastic disease is selected from the group consisting of pancreatic cancer, gastric cancer, esophageal cancer, ovarian cancer and lung cancer.

[0084] array Sequence number 1 GYXFTSYWIG The third X is T or S. SEQ ID NO: 2 GXIYPXXXXTXYX the second X is N or I; the sixth X is S or G; the seventh X is A, E or D; the eighth X is A or S; the ninth X is Y or D; the eleventh X is N or R; and the last X is A or S. SEQ ID NO:3 XRXWRGNSFDX the first X is A or T; the third X is L, M, I or Q; and the last X is A or Y. SEQ ID NO: 4 KSSQSXLNSGNQKNYLX The sixth X is L or V; the last X is T or A. SEQ ID NO:5 WASTRES SEQ ID NO:6 QXDYSYPXT the second X is N or Q; the eighth X is L or F. SEQ ID NO:7 GYSFTSYWIG SEQ ID NO:8 GYTFTSYWIG SEQ ID NO:9 GNIYPGASDTRYA SEQ ID NO:10 GNIYPGDADTRYA SEQ ID NO:11 GIIYPGASDTNYA SEQ ID NO:12 GIIYPGDAYTRYS SEQ ID NO:13 GIIYPGAAYTRYA SEQ ID NO:14 GNIYPGASYTRYS SEQ ID NO:15 GNIYPGEAYTRYS SEQ ID NO:16 GNIYPSESYTNYA SEQ ID NO:17 GIIYPSAAYTRYA SEQ ID NO:18 ARLWRGNSFDY SEQ ID NO:19 ARMWRGNSFDY Sequence number 20: ARIWRGNSFDY SEQ ID NO:21 TRLWRGNSFDA SEQ ID NO:22 TRQWRGNSFDY SEQ ID NO:23 TRLWRGNSFDY SEQ ID NO:24 TRMWRGNSFDY SEQ ID NO: 25 KSSQSLLNSGNQKNYLA SEQ ID NO:26 KSSQSLLNSGNQKNYLT SEQ ID NO:27 KSSQSVLNSGNQKNYLT SEQ ID NO:28 KSSQSVLNSGNQKNYLA SEQ ID NO:29 QNDYSYPFT SEQ ID NO:30 QNDYSYPLT SEQ ID NO:31 QQDYSYPFT SEQ ID NO:32 hGBA-1 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGNIYPGASDTRYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCARLWRGNSFDYWGQGTLVTVSS SEQ ID NO: 33 hGBA-1, hGBA-2, hGBA-6, hGBA-8 light chain variable region DIVMTQSPDSLAVSLGERATINCKSSQSLLNSGNQKNYLAWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQNDYSYPFTFGQGTKVEIK SEQ ID NO:34 hGBA-2 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGNIYPGDADTRYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCARMWRGNSFDYWGQGTLVTVSS SEQ ID NO: 35 hGBA-3 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGIIYPGASDTNYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCARIWRGNSFDYWGQGTLVTVSS SEQ ID NO:36 hGBA-3 light chain variable region DIVMTQSPDSLAVSLGERATINCKSSQSLLNSGNQKNYLAWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQNDYSYPLTFGQGTKVEIK SEQ ID NO: 37 hGBA-4 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGIIYPGDAYTRYSPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRLWRGNSFDAWGQGTLVTVSS SEQ ID NO: 38 hGBA-4 light chain variable region DIVMTQSPDSLAVSLGERATINCKSSQSLLNSGNQKNYLTWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQNDYSYPLTFGQGTKVEIK SEQ ID NO: 39 hGBA-5 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGIIYPGAAYTRYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCARLWRGNSFDYWGQGTLVTVSS SEQ ID NO: 40 hGBA-5 light chain variable region DIVMTQSPDSLAVSLGERATINCKSSQSLLNSGNQKNYLAWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQQDYSYPFTFGQGTKVEIK SEQ ID NO: 41 hGBA-6 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYTFTSYWIGWVRQMPGKGLEWMGNIYPGASYTRYSPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRQWRGNSFDYWGQGTLVTVSS SEQ ID NO: 42 hGBA-7 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGNIYPGEAYTRYSPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRLWRGNSFDYWGQGTLVTVSS SEQ ID NO: 43 hGBA-7 light chain variable region DIVMTQSPDSLAVSLGERATINCKSSQSVLNSGNQKNYLTWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQNDYSYPFTFGQGTKVEIK SEQ ID NO: 44 hGBA-8 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGNIYPSESYTNYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRLWRGNSFDYWGQGTLVTVSS SEQ ID NO: 45 hGBA-9 heavy chain variable region EVQLVQSGAEVKKPGESLKISCKGSGYTFTSYWIGWVRQMPGKGLEWMGIIYPSAAYTRYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRMWRGNSFDYWGQGTLVTVSS SEQ ID NO: 46 hGBA-9 light chain variable region DIVMTQSPDSLAVSLGERATINCKSSQSVLNSGNQKNYLAWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQQDYSYPFTFGQGTKVEIK SEQ ID NO: 47 IMAB362 full length heavy chain QVQLQQPGAELVRPGASVKLSCKASGYTFTSYWINWVKQRPGQGLEWIGNIYPSDSYTNYNQKFKDKATLTVDKSSSTAYMQLSSPTSEDSAVYYCTRSWRGNSFDYWGQGT TLTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO: 48 IMAB362 full length light chain DIVMTQSPSSLTVTAGEKVTMSCKSSQSLLNSGNQKNYLTWYQQKPGQPPKLLIYWASTRESGVPDRFTGSGSGTDFTLTISSVQAEDLAVYYCQNDYSYPFTFGSGTKL EIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC SEQ ID NO: 49 Full length of hGBA-1 heavy chain EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGNIYPGASDTRYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCARLWRGNSFDYWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO: 50 Full length of hGBA-1, hGBA-2, hGBA-6, hGBA-8 light chain DIVMTQSPDSLAVSLGERATINCKSSQSLLNSGNQKNYLAWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQNDYSYPFTFGQGTKV EIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC SEQ ID NO:51 Full length of hGBA-2 heavy chain EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGNIYPGDADTRYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCARMWRGNSFDYWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:52 Full length of hGBA-3 heavy chain EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGIIYPGASDTNYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCARIWRGNSFDYWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:53 Full length of hGBA-3 light chain DIVMTQSPDSLAVSLGERATINCKSSQSLLNSGNQKNYLAWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQNDYSYPLTFGQGTKV EIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC SEQ ID NO:54 Full length of hGBA-4 heavy chain EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGIIYPGDAYTRYSPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRLWRGNSFDAWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:55 Full length of hGBA-4 light chain DIVMTQSPDSLAVSLGERATINCKSSQSLLNSGNQKNYLTWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQNDYSYPLTFGQGTKV EIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC SEQ ID NO:56 Full length of hGBA-5 heavy chain EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGIIYPGAAYTRYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCARLWRGNSFDYWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:57 hGBA-5 full length light chain DIVMTQSPDSLAVSLGERATINCKSSQSLLNSGNQKNYLAWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQQDYSYPFTFGQGTKV EIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC SEQ ID NO:58 Full length of hGBA-6 heavy chain EVQLVQSGAEVKPGESLKISCKGSGYTFTSYWIGWVRQMPGKGLEWMGNIYPGASYTRYSPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRQWRGNSFDYWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:59 Full length of hGBA-7 heavy chain EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGNIYPGEAYTRYSPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRLWRGNSFDYWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO: 60 hGBA-7 full length light chain DIVMTQSPDSLAVSLGERATINCKSSQSVLNSGNQKNYLTWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQNDYSYPFTFGQGTKV EIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC SEQ ID NO:61 Full length of hGBA-8 heavy chain EVQLVQSGAEVKKPGESLKISCKGSGYSFTSYWIGWVRQMPGKGLEWMGNIYPSESYTNYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRLWRGNSFDYWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:62 Full length of hGBA-9 heavy chain EVQLVQSGAEVKKPGESLKISCKGSGYTFTSYWIGWVRQMPGKGLEWMGIIYPSAAYTRYAPSFQGQVTISADKSISTAYLQWSSLKASDTAMYYCTRMWRGNSFDYWGQGT LVTVSSASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKT HTCPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:63 hGBA-9 full length light chain DIVMTQSPDSLAVSLGERATINCKSSQSVLNSGNQKNYLAWYQQKPGQPPKLLIYWASTRESGVPDRFSGSGSGTDFTLTISSLQAEDVAVYYCQQDYSYPFTFGQGTKV EIKRTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC SEQ ID NO:64 Heavy chain constant region - CH1+Fc domain ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPELLGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGV EVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:65 RTVAAPSVFIFPPSDEQLKSGTASVVCLLNNFYPREAKVQWKVDNALQSGNSQESVTEQDSKDSTYSLSSTLTLSKADYEKHKVYACEVTHQGLSSPVTKSFNRGEC SEQ ID NO:66 ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPEAAGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGV EVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:67 ASTKGPSVFPLAPSSKSTSGGTAALGCLVKDYFPEPVTVSWNSGALTSGVHTFPAVLQSSGLYSLSSVVTVPSSSLGTQTYICNVNHKPSNTKVDKKVEPKSCDKTHTCPPCPAPEAAGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKFNWYVDGV EVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALGAPIEKTISKAKGQPREPQVYTLPPSRDELTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTPPVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK SEQ ID NO:68 DQWSTQDLYN SEQ ID NO:69 NNPVTAVFNYQ SEQ ID NO:70 STQDLYNNPVTAVF SEQ ID NO:71 TNFWMSTANMYTG SEQ ID NO:72 ALMIVGIVLGAIGLLV SEQ ID NO:73 RIGSMEDSAKANMTLTSGIMFIVS SEQ ID NO:74 METDTLLLWVLLLWVPGSTGDAAQPARRARRTKLGTELGSTPVWWNSADGRMDQWSTQDLYNNPVTAVFNYQGLWRSCVRESSGFTECRGYFTLLGLPAMLQAVRAAIQHSGGRSRRARTKTHLRRGSE Sequence number 75 MDQWSTQDLYNNPVT SEQ ID NO:76 LYNNPVTAVFNYQGL SEQ ID NO:77 VFNYQGLWRSCVRES SEQ ID NO:78 QGLWRSCVRESSGFT SEQ ID NO:79 RSCVRESSGFTECRG Sequence number 80 TEDEVQSYPSKHDYV SEQ ID NO:81 EVQSYPSKHDYV SEQ ID NO: 82 Consensus sequence containing heavy chain CDR1 of IMAB362 GYXFTSYWIX The third X is T or S and the last X is G or N. SEQ ID NO: 83: Consensus sequence containing the heavy chain CDR2 of IMAB362 GXIYPXXXXTXYX the second X is N or I; the sixth X is S or G; the seventh X is A, E or D; the eighth X is A or S; the ninth X is Y or D; the eleventh X is N or R; and the last X is A, N or S. SEQ ID NO: 84: Consensus sequence containing the heavy chain CDR3 of IMAB362 XRXWRGNSFDX the first X is A or T; the third X is L, M, I, S or Q; and the last X is A or Y. SEQ ID NO: 85 ggctatagctttacatcatattggattgga SEQ ID NO:86 gggaacatttaccctggggcatcggatacgcgatacgca SEQ ID NO: 87 gcgagactttggcgggggaatagcttcgactac SEQ ID NO: 88 aaaagctcccaaagcctattgaactcgggaaaccaaaagaattacttggca SEQ ID NO:89 tgggcaagcacccgagagagc SEQ ID NO: 90 caaaacgactattcatacccattcaca SEQ ID NO: 91 ggatattcatttacaagctactggatcgga SEQ ID NO: 92 ggaaatatataccccggagacgcggacacgagatacgca SEQ ID NO: 93 gcgcggatgtggcgcggcaatagctttgactac SEQ ID NO: 94 gggatcatctatccgggggcatccgataccaactatgcg SEQ ID NO: 95 gctaggatttggcgaggaaatagctttgattat SEQ ID NO: 96 aagagctcgcaaagtttgctgaactccgggaaccaaaagaattacctggca SEQ ID NO:97 tgggcatcaacgcgggaaagc SEQ ID NO:98 caaaacgactactcctatccgctgacc SEQ ID NO:99 ggatactcatttacatcatactggatagga SEQ ID NO: 100 gggattatataccccggcgacgcttacactcgatattcg SEQ ID NO: 101 acgaggctatggagggggaatagctttgatgcc SEQ ID NO: 102 aagagctcccaaagcctattgaactcgggaaatcaaaagaattatctgaca SEQ ID NO:103 tgggcctcgacaagggagagc SEQ ID NO: 104 caaaatgactactcatacccgctgaca SEQ ID NO: 105 ggatatagctttacgagctactggatcgga SEQ ID NO: 106 gggataatataccccggagcggcatacacgagatatgcg SEQ ID NO: 107 gcgagactatggcgcgggaactcatttgattac SEQ ID NO: 108 aaatcatcgcaatcattgctaaattcggggaaccaaaagaattatttggca SEQ ID NO: 109 tgggcatccacgagagaatcg SEQ ID NO:110 caacaagattattcatacccatttaca SEQ ID NO: 111 ggatatacatttacatcttactggatcgga SEQ ID NO: 112 gggaacatttatcctggcgcgagctatacgcgctat SEQ ID NO: 113 acccggcaatggaggggcaatagctttgactac SEQ ID NO: 114 ggatattcctttacatcatactggatcggc SEQ ID NO: 115 gggaacatatatcccggagaagcctatacgagatactcg SEQ ID NO: 116 acgcgactatggaggggaaatagctttgactat SEQ ID NO: 117 aagagctcccaatcagtcctgaactctgggaatcaaaagaattacctgaca SEQ ID NO: 118 tgggcgagcacgagggagagc SEQ ID NO: 119 caaaatgattattcataccccttcaca SEQ ID NO: 120 ggatactcctttacatcatattggatcgga SEQ ID NO: 121 ggaaacatatatccgagcgaatcatatacgaactacgcg SEQ ID NO: 122 acgaggctatggagggggaatagcttcgactat SEQ ID NO: 123 ggatatacattcacgagctactggatagga SEQ ID NO: 124 ggaatcatatatccttccgcggcatatacgcgatatgcg SEQ ID NO: 125 acgcggatgtggaggggaaatagctttgattac SEQ ID NO: 126 aagagctcgcaatcggtcctgaatagcgggaaccaaaagaattatctggcc SEQ ID NO:127 caacaagactactcatacccatttaca SEQ ID NO:128 gaagtccaactggtccaatccggcgcggaggttaagaagcccggagaatcgctgaagatctcatgcaaagggagcggctatagctttacatcatattggattggatgggtcaggcaaatgccggggaaggggctggaatggatggggaacatttaccctggggcatcggatacgcga tacgcacctagctttcaagggcaagtcacaatttcggcggacaagagcatctcaacggcatacctgcaatggtcgagcttgaaggcatctgatactgcaatgtactactgcgcgagactttggcgggggaatagcttcgactactgggggcagggtaccctggttacggtctcgagc SEQ ID NO:129 gacattgtgatgacgcaaagccccgattcgctggcttatcgctaggggagcggctacgatcaattgcaaaagctcccaaagcctattgaactcgggaaaccaaaagaattacttggcatggtatcaacaaaaaccggggcaaccgccgaagctgctgatctattggg caagcacccgagagagcggtgtcccggaccgatttagcgggagcggatcgggcaccgacttcacgctgacaataagctcattgcaagccgaggatgtggcggtctattattgccaaaacgactattcataccattcacattcgggcaaggtaccaaggtcgagatcaag sequence number 130 gaagtccaactggtccaatctggagcggaagtcaagaagcctggggagagcctgaaaatttcatgcaaggggagcggatattcatttacaagctactggatcggatgggtccggcaaatgccgggggaagggcttggaatggatgggaaatatataccccggagacgcggacacgaga tacgcaccgagctttcaagggcaggtcaccattagcgctgataaatcgatttcaaccgcatatctgcaatggtcatcgctgaaggcctccgacaccgcgatgtactattgcgcgcggatgtggcgcggcaatagctttgactactggggcagggtaccctcgtcacggtctcgagc sequence number 131 gaggtccaactggtccaaagcggcgcggaggtcaagaagccgggagaatccctgaagattagctgcaaaggctccgggctatagctttacatcatattggatcggatgggtcagacaaatgccgggaaagggacttgaatggatggggatcatctatccgggggcatccgataccaac tatgcgccgagcttccaagggcaggtcacgatatccgcggataaatcgattagcaccgcatatctgcaatggagctcgctgaaggcatccgacaccgcgatgtactactgcgctaggatttggcgaggaaatagctttgattattggggcagggtacccttgtcacggtctcgagc sequence number 132 gacattgtcatgacgcaaagccccgactcgctggccgtctcactggggagcgggcgacaatcaactgcaagagctcgcaaagtttgctgaactccgggaaccaaaagaattacctggcatggtatcaacaaaagccggggcaacccccgaagctgctgatatattggg catcaacgcgggaaagcggagatcccggatagatttagcggatctggatcggggaccgacttcacgctgacgatatctagccttcaagccgaggatgtggctgtatattattgccaaaacgactactcctatccgctgaccttcgggcaaggtaccaaggtcgagatcaag sequence number 133 gaagtccaactagtccaaagcggagccgaagtcaagaaaccgggggagagccttaagatctcatgcaaggggagcggatactcatttacatcatactggataggatgggtcagacaaatgcccggcaaggggctggaatggatggggattatataccccggcgacgcttacactcga tattcgccatcattccaagggcaggtcacgatatcggccgataaatcgatatccacggcatacctgcaatggagctcactgaaagcatctgatacggcaatgtattattgcacgaggctatggaggggaatagctttgatgcctggggcagggtaccctggtcacggtctcgagc sequence number 134 gacatagttatgacacaatcgccggatagcctcgcggtcagccttggagagcgggcgacgatcaactgcaagagctcccaaagcctattgaactcgggaaatcaaaagaattatctgacatggtatcaacaaaagccggggcaaccaccgaaactgctgatctattggg cctcgacaagggagagcggagtcccggaccgcttctctggatcgggaagcgggactgacttcacgctgaccataagctcgctgcaagccgaggacgtcgccgtctattattgccaaaatgactactcatacccgctgacatttggccaaggtaccaaggtcgagatcaag sequence number 135 gaggtgcaactggtacaatccggggcggaagtgaagaagccgggggaatcgctgaagataagctgcaaaggctctggatatagctttacgagctactggatcggatgggtcaggcaaatgccgggggaagggactggaatggatggggataatatacccggagcggcatacacgaga tatgcgccgagcttccaagggcaagtgacaataagcgcggacaaatcgattagcacggcatatctgcaatggtcctcgctgaaggcgagcgataccgcaatgtactattgcgcgagactatggcgcgggaactcatttgattactggggcagggtaccctagtgacggtctcgagc sequence number 136 gacattgtcatgacgcaaagcccggatagcctggctttatcgctggggagagagcgacgatcaactgcaaatcatcgcaatcattgctaaattcgggggaaccaaaagaattattggcatggtatcaacaaaagccggggcaaccgccgaaactgctgatttactggg catccacgagagaatcgggagtcccggaccgatttagcggatctgggagcgggaccgatttcacgctgaccattagctcgctgcaagcggaggatgtggcggtctattactgccaacaagattatcataccatttacatttgggcaaggtaccaaggtcgagatcaag sequence number 137 gaagtacaattggttcaatcgggggccgaagtcaagaagccgggggaatcgctgaagatatcctgcaaggggagcggatatacatttacatcttactggatcggatgggtcagacaaatgcccggaaagggggcttgaatggatgggggaacatttatcctggcgcgagctatacgcgc tatagcccgagcttccaagggcaggtcacgattagcgccgacaagagcatttcgacggcatacctgcaatggagctcgctgaaagcatcggatacggcaatgtattactgcacccggcaatggaggggcaatagctttgactactggggcagggtaccctagtcacggtctcgagc sequence number 138 gaagttcaattggtccaatctggagccgaagtcaagaagcccggagaatcgctgaagattagctgcaaggggagcggatattcctttacatcatactggatcggctgggtcagacaaatgcccggaaagggactggaatggatggggaacatatatcccggagaagcctatacgaga tactcgccatcatttcaaggacaggtcaccataagcgcggacaagagcataagcaccgcatacctgcaatggagctcgctgaaggcatcggacaccgccatgtattactgcacgcgactatggaggggaaatagctttgactattggggcagggtaccttagtcacggtctcgagc sequence number 139 gatatagtaatgactcaatcacccgatagcttggctgtgagcctgggagaaagagctacaatcaactgcaagagctcccaatcagtcctgaactctgggaatcaaaagaattacctgacatggtatcaacaaaagcccggacaaccgccgaagctgctgatctactgggcgagcacgagggagagcggagtcccggatcgattttctggctccgggagcggaaccgacttcacactgactattagctcgctgcaagcggaggacgtcgccgtctactattgccaaaatgattattcataccccttcacatttgggcaaggtaccaaggtcgagatcaag Sequence number 140 gaggtgcaactagtgcaatcgggggccgaagtgaagaaacctggggaatcgctgaagatatcatgcaaggggagcggatactcctttacatcatattggatcggatgggtcaggcaaatgccggggaaggggctggaatggatgggaaacatatatccgagcgaatcatatacgaactacgcgccgagctttcaaggacaagtcacgatatccgcggataaatcgatatcgaccgcatacctgcaatggagctcgctgaaggcttccgacactgcgatgtattactgcacgaggctatggagggggaatagcttcgactattgggggcagggtaccctggtgacggtctcgagc Sequence number 141 gaagtccaattagtccaatcgggggccgaggtcaagaagccgggggaatcgctcaagataagctgcaagggatcgggatatacattcacgagctactggataggatgggtcaggcaaatgccggggaaggggctggaatggatgggaatcatatatccttccgcggcatatacgcga tatgcgccatcatttcaaggacaggtcacgataagcgccgacaagagcattagcaccgcatacctgcaatggtcgagccttaaggcatcggacaccgcgatgtactactgcacgcggatgtggaggggaaatagctttgattactgggggcagggtaccctagtcacggtctcgagc SEQ ID NO:142 gacatcgtcatgacgcaaagcccggactcgctggcggtctcgctgggggagcggggccacaataaattgcaagagctcgcaatcggtcctgaatagcgggaaccaaaagaattatctggcctggtatcaacaaaagccggggcaaccaccgaagctgctaatctattggg cgagcacgaggagagcggagtccccgatcgatttagcggatcgggaagcgggaccgatttcacgctgacgatttcgagcctacaagccgaggatgtggcggtctattactgccaacaagactactcatacccatttacatttggacaaggtaccaaggtcgagatcaag SEQ ID NO: 143 Sortase tag RLPXTGG X is any of the 20 naturally occurring amino acids. SEQ ID NO: 144 Sortase tag GGGGSLPXTGG X is any of the 20 naturally occurring amino acids.

[0085] References Alegre, M. L., A. M. Collins, V. L. Pulito, R. A. Brosius, W. C. Olson, R. A. Zivin, R. Knowles, J. R. Thistlethwaite, L. K. Jolliffe, and J. A. Bluestone. 1992. 'Effect of a single amino acid mutation on the activating and immunosuppressive properties of a "humanized" OKT3 monoclonal antibody', J Immunol, 148: 3461-8. An, Z., G. Forrest, R. Moore, M. Cukan, P. Haytko, L. Huang, S. Vitelli, J. Z. Zhao, P. Lu, J. Hua, C. R. Gibson, B. R. Harvey, D. Montgomery, D. Zaller, F. Wang, and W. Strohl. 2009. 'IgG2m4, an engineered antibody isotype with reduced Fc function', MAbs, 1: 572-9. Bolt, S., E. Routledge, I. Lloyd, L. Chatenoud, H. Pope, S. D. Gorman, M. Clark, and H. Waldmann. 1993. 'The generation of a humanized, non-mitogenic CD3 monoclonal antibody which retains in vitro immunosuppressive properties', Eur J Immunol, 23: 403-11. Chang, Z. L., and Y. Y. Chen. 2017. 'CARs: Synthetic Immunoreceptors for Cancer Therapy and Beyond', Trends Mol Med, 23: 430-50. Chu, S. Y., I. Vostiar, S. Karki, G. L. Moore, G. A. Lazar, E. Pong, P. F. Joyce, D. E. Szymkowski, and J. R. Desjarlais. 2008. 'Inhibition of B cell receptor-mediated activation of primary human B cells by coengagement of CD19 and FcgammaRIIb with Fc-engineered antibodies', Mol Immunol, 45: 3926-33. Dall'Acqua, W. F., R. M. Woods, E. S. Ward, S. R. Palaszynski, N. K. Patel, Y. A. Brewah, H. Wu, P. A. Kiener, and S. Langermann. 2002. 'Increasing the affinity of a human IgG1 for the neonatal Fc receptor: biological consequences', J Immunol, 169: 5171-80. Diebolder, C. A., F. J. Beurskens, R. N. de Jong, R. I. Koning, K. Strumane, M. A. Lindorfer, M. Voorhorst, D. Ugurlar, S. Rosati, A. J. Heck, J. G. van de Winkel, I. A. Wilson, A. J. Koster, R. P. Taylor, E. O. Saphire, D. R. Burton, J. Schuurman, P. Gros, and P. W. Parren. 2014. 'Complement is activated by IgG hexamers assembled at the cell surface', Science, 343: 1260-3. Ellerman, D. 2019. 'Bispecific T-cell engagers: Towards understanding variables influencing the in vitro potency and tumor selectivity and their modulation to enhance their efficacy and safety', Methods, 154: 102-17. Green, M. R., and J. Sambrook. 2012. Molecular Cloning: A Laboratory Manual (Fourth Edition) (Cold Spring Harbor Laboratory Press). Hashimoto, Y., W. Zhou, K. Hamauchi, K. Shirakura, T. Doi, K. Yagi, T. Sawasaki, Y. Okada, M. Kondoh, and H. Takeda. 2018. 'Engineered membrane protein antigens successfully induce antibodies against extracellular regions of claudin-5', Sci Rep, 8: 8383. Hewitt, KJ, R. Agarwal, and PJ Morin. 2006. 'The claudin gene family: expression in normal and neoplastic tissues', BMC Cancer, 6: 186. Idusogie, EE, PY Wong, LG Presta, H. Gazzano-Santoro, K. Totpal, M. Ultsch, and MG Mulkerrin. 2001. 'Engineered antibodies with increased activity to recruit complement', J Immunol, 166: 2571-5. In S. Duebel and JM Reichert (eds.), Handbook of Therapeutic Antibodies, Second Edition (Wiley-VCH Verlag GmbH & Co. KGaA.) Presser, and H. Kaufmann. 2014. 'Process Development and Manufacturing of Therapeutic Antibodies. Jiang, H., Z. Shi, P. Wang, C. Wang, L. Yang, G. Du, H. Zhang, B. Shi, J. Jia, Q. Li, H. Wang, and Z. Li. 2018. 'Claudin18.2-Specific Chimeric Antigen Receptor Engineered T Cells for the Treatment of Gastric Cancer', J Natl Cancer Inst. June, C. H., and M. Sadelain. 2018. 'Chimeric Antigen Receptor Therapy', N Engl J Med, 379: 64-73. Lazar, G. A., W. Dang, S. Karki, O. Vafa, J. S. Peng, L. Hyun, C. Chan, H. S. Chung, A. Eivazi, S. C. Yoder, J. Vielmetter, D. F. Carmichael, R. J. Hayes, and B. I. Dahiyat. 2006. 'Engineered antibody Fc variants with enhanced effector function', Proc Natl Acad Sci U S A, 103: 4005-10. Leabman, M. K., Y. G. Meng, R. F. Kelley, L. E. DeForge, K. J. Cowan, and S. Iyer. 2013. 'Effects of altered FcgammaR binding on antibody pharmacokinetics in cynomolgus monkeys', MAbs, 5: 896-903. Lo, M., Kim HS, Tong RK, Bainbridge TW, Vernes JM, Zhang Y, Lin YL, Chung S, Dennis MS, Zuchero YJ, Watts RJ, Couch JA, Meng YG, Atwal JK, Brezski RJ, Spiess C, and Ernst JA. 2017. 'Effector-attenuating substitutions that maintain antibody stability and reduce toxicity in mice', J Biol Chem, 292: 3900-08. In the Handbook of Therapeutic Antibodies, Second Edition (Wiley-VCH Verlag GmbH & Co. KGaA.) by Martin, ACR, and J. Allemn. 2014. 'Bioinformatics Tools for Analysis of Antibodies.' Mimoto , F. , T. Igawa , T. Kuramochi , H. Katada , S. Kadono , T. Kamikawa , M. Shida-Kawazoe , and K. Hattori . 2013. 'Novel asymmetrically engineered antibody Fc variant with superior FcgammaR binding affinity and specificity compared with afucosylated Fc variant', MAbs, 5:229-36. Moore, G. L., H. Chen, S. Karki, and G. A. Lazar. 2010. 'Engineered Fc variant antibodies with enhanced ability to recruit complement and mediate effector functions', MAbs, 2: 181-9. Natsume, A., M. In, H. Takamura, T. Nakagawa, Y. Shimizu, K. Kitajima, M. Wakitani, S. Ohta, M. Satoh, K. Shitara, and R. Niwa. 2008. 'Engineered antibodies of IgG1 / IgG3 mixed isotype with enhanced cytotoxic activities', Cancer Res, 68: 3863-72. Niimi, T., K. Nagashima, J. M. Ward, P. Minoo, D. B. Zimonjic, N. C. Popescu, and S. Kimura. 2001. 'claudin-18, a novel downstream target gene for the T / EBP / NKX2.1 homeodomain transcription factor, encodes lung- and stomach-specific isoforms through alternative splicing', Mol Cell Biol, 21: 7380-90. Richards, J. O., S. Karki, G. A. Lazar, H. Chen, W. Dang, and J. R. Desjarlais. 2008. 'Optimization of antibody binding to FcgammaRIIa enhances macrophage phagocytosis of tumor cells', Mol Cancer Ther, 7: 2517-27. Rother, RP, SA Rollins, CF Mojcik, RA Brodsky, and L. Bell. 2007. 'Discovery and development of the complement inhibitor eculizumab for the treatment of paroxysmal nocturnal hemoglobinuria', Nat Biotechnol, 25: 1256-64. Sahin, U., M. Koslowski, K. Dhaene, D. Usener, G. Brandenburg, G. Seitz, C. Huber, and O. Tureci. 2008. Claudin-18 splice variant 2 is a pan-cancer target suitable for therapeutic antibody development, Clin Cancer Res, 14:7624-34. In S. Duebel and JM Reichert (eds.), Handbook of Therapeutic Antibodies, Second Edition (Wiley-VCH Verlag GmbH & Co. KGaA.) Saldanha, JW 2014. 'Humanization Strategies.' In S. Duebel and JM Reichert (eds.), Handbook of Therapeutic Antibodies, Second Edition (Wiley-VCH Verlag GmbH & Co. KGaA.). Shang, L., B. Daubeuf, M. Triantafilou, R. Olden, F. Depis, A. C. Raby, S. Herren, A. Dos Santos, P. Malinge, I. Dunn-Siegrist, S. Benmkaddem, A. Geinoz, G. Magistrelli, F. Rousseau, V. Buatois, S. Salgado-Pires, W. Reith, R. Monteiro, J. Pugin, O. Leger, W. Ferlin, M. Kosco-Vilbois, K. Triantafilou, and G. Elson. 2014. 'Selective antibody intervention of Toll-like receptor 4 activation through Fc gamma receptor tethering', J Biol Chem, 289: 15309-18. Shields, R. L., A. K. Namenuk, K. Hong, Y. G. Meng, J. Rae, J. Briggs, D. Xie, J. Lai, A. Stadlen, B. Li, J. A. Fox, and L. G. Presta. 2001. 'High resolution mapping of the binding site on human IgG1 for Fc gamma RI, Fc gamma RII, Fc gamma RIII, and FcRn and design of IgG1 variants with improved binding to the Fc gamma R', J Biol Chem, 276: 6591-604. Stavenhagen, J. B., S. Gorlatov, N. Tuaillon, C. T. Rankin, H. Li, S. Burke, L. Huang, S. Vijh, S. Johnson, E. Bonvini, and S. Koenig. 2007. 'Fc optimization of therapeutic antibodies enhances their ability to kill tumor cells in vitro and controls tumor expansion in vivo via low-affinity activating Fcgamma receptors', Cancer Res, 67: 8882-90. Tao, M. H., and S. L. Morrison. 1989. 'Studies of aglycosylated chimeric mouse-human IgG. Role of carbohydrate in the structure and effector functions mediated by the human IgG constant region', J Immunol, 143: 2595-601. Vafa, O., G. L. Gilliland, R. J. Brezski, B. Strake, T. Wilkinson, E. R. Lacy, B. Scallon, A. Teplyakov, T. J. Malia, and W. R. Strohl. 2014. 'An engineered Fc variant of an IgG eliminates all immune effector functions via structural perturbations', Methods, 65: 114-26. Waldmeier, L., I. Hellmann, C. K. Gutknecht, F. I. Wolter, S. C. Cook, S. T. Reddy, U. Grawunder, and R. R. Beerli. 2016. 'Transpo-mAb display: Transposition-mediated B cell display and functional screening of full-length IgG antibody libraries', MAbs, 8: 726-40. Walker, M. R., J. Lund, K. M. Thompson, and R. Jefferis. 1989. 'Aglycosylation of human IgG1 and IgG3 monoclonal antibodies can eliminate recognition by human cells expressing Fc gamma RI and / or Fc gamma RII receptors', Biochem J, 259: 347-53. Wang, X., M. Mathieu, and R. J. Brezski. 2018. 'IgG Fc engineering to modulate antibody effector functions', Protein Cell, 9: 63-73. Xu, D., M. L. Alegre, S. S. Varga, A. L. Rothermel, A. M. Collins, V. L. Pulito, L. S. Hanna, K. P. Dolan, P. W. Parren, J. A. Bluestone, L. K. Jolliffe, and R. A. Zivin. 2000. 'In vitro characterization of five humanized OKT3 effector function variant antibodies', Cell Immunol, 200: 16-26. Yu, D., and J. R. Turner. 2008. 'Stimulus-induced reorganization of tight junction structure: the role of membrane traffic', Biochim Biophys Acta, 1778: 709-16. Zalevsky, J., A. K. Chamberlain, H. M. Horton, S. Karki, I. W. Leung, T. J. Sproule, G. A. Lazar, D. C. Roopenian, and J. R. Desjarlais. 2010. 'Enhanced antibody half-life improves in vivo activity', Nat Biotechnol, 28: 157-9. CN109762067 WO2000 / 015659 WO2004 / 047863 WO2005 / 113587 WO2007 / 059997 WO2008 / 145338 WO2013 / 167259 WO2013 / 174509 WO2014 / 075788 WO2014 / 127906 WO2016 / 166122 WO2018 / 006882 WO2019 / 175617 WO2019 / 219089

Claims

1. An antibody or antigen-binding fragment thereof that binds to CLDN18.2, comprising an HCDR1 sequence of SEQ ID NO: 1, an HCDR2 sequence of SEQ ID NO: 2, and an HCDR3 sequence of SEQ ID NO: 3, and an LCDR1 sequence of SEQ ID NO: 4, an LCDR2 sequence of SEQ ID NO: 5, and an LCDR3 sequence of SEQ ID NO: 6; a. the HCDR1 sequence of SEQ ID NO: 7, the HCDR2 sequence of SEQ ID NO: 9 and the HCDR3 sequence of SEQ ID NO: 18, and the LCDR1 sequence of SEQ ID NO: 25, the LCDR2 sequence of SEQ ID NO: 5 and the LCDR3 sequence of SEQ ID NO: 29; b. the HCDR1 sequence of SEQ ID NO: 7, the HCDR2 sequence of SEQ ID NO: 10 and the HCDR3 sequence of SEQ ID NO: 19, and the LCDR1 sequence of SEQ ID NO: 25, the LCDR2 sequence of SEQ ID NO: 5 and the LCDR3 sequence of SEQ ID NO: 29; c. the HCDR1 sequence of SEQ ID NO: 7, the HCDR2 sequence of SEQ ID NO: 10 and the HCDR3 sequence of SEQ ID NO: 20, and the LCDR1 sequence of SEQ ID NO: 25, the LCDR2 sequence of SEQ ID NO: 5 and the LCDR3 sequence of SEQ ID NO: 30; d. the HCDR1 sequence of SEQ ID NO: 7, the HCDR2 sequence of SEQ ID NO: 12 and the HCDR3 sequence of SEQ ID NO: 21, and the LCDR1 sequence of SEQ ID NO: 26, the LCDR2 sequence of SEQ ID NO: 5 and the LCDR3 sequence of SEQ ID NO: 30; e. the HCDR1 sequence of SEQ ID NO: 7, the HCDR2 sequence of SEQ ID NO: 13 and the HCDR3 sequence of SEQ ID NO: 18, and the LCDR1 sequence of SEQ ID NO: 25, the LCDR2 sequence of SEQ ID NO: 5 and the LCDR3 sequence of SEQ ID NO: 31; f. the HCDR1 sequence of SEQ ID NO:8, the HCDR2 sequence of SEQ ID NO:14, and the HCDR3 sequence of SEQ ID NO:22, and the LCDR1 sequence of SEQ ID NO:25, the LCDR2 sequence of SEQ ID NO:5, and the LCDR3 sequence of SEQ ID NO:29; g. the HCDR1 sequence of SEQ ID NO: 7, the HCDR2 sequence of SEQ ID NO: 15 and the HCDR3 sequence of SEQ ID NO: 23, and the LCDR1 sequence of SEQ ID NO: 27, the LCDR2 sequence of SEQ ID NO: 5 and the LCDR3 sequence of SEQ ID NO: 29; h. the HCDR1 sequence of SEQ ID NO: 7, the HCDR2 sequence of SEQ ID NO: 16, and the HCDR3 sequence of SEQ ID NO: 23, and the LCDR1 sequence of SEQ ID NO: 25, the LCDR2 sequence of SEQ ID NO: 5, and the LCDR3 sequence of SEQ ID NO: 29; or i. HCDR1 sequence of SEQ ID NO: 8, HCDR2 sequence of SEQ ID NO: 17, and HCDR3 sequence of SEQ ID NO: 24, and LCDR1 sequence of SEQ ID NO: 28, LCDR2 sequence of SEQ ID NO: 5, and LCDR3 sequence of SEQ ID NO: 31 An antibody or antigen-binding fragment thereof comprising:

2. a. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 32; b. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 34; c. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 35; d. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 37; e. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 39; f. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 41; g. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 42; h. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 44; or i. a VH sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 45; j. a VL sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 33; k. a VL sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 36; l. a VL sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 38; m. a VL sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 40; n. a VL sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 43; or o. A VL sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:

46. and The antibody or antigen-binding fragment thereof according to claim 1, wherein the CDR regions of the VH sequence and the VL sequence have the CDR sequences described in claim 1.

3. a. the VH sequence of SEQ ID NO: 32 and the VL sequence of SEQ ID NO: 33; b. the VH sequence of SEQ ID NO: 34 and the VL sequence of SEQ ID NO: 33; c. the VH sequence of SEQ ID NO: 35 and the VL sequence of SEQ ID NO: 36; d. the VH sequence of SEQ ID NO: 37 and the VL sequence of SEQ ID NO: 38; e. the VH sequence of SEQ ID NO: 39 and the VL sequence of SEQ ID NO: 40; f. the VH sequence of SEQ ID NO: 41 and the VL sequence of SEQ ID NO: 33; g. the VH sequence of SEQ ID NO: 42 and the VL sequence of SEQ ID NO: 43; h. the VH sequence of SEQ ID NO: 44 and the VL sequence of SEQ ID NO: 33; or i. The VH sequence of SEQ ID NO: 45 and the VL sequence of SEQ ID NO: 46 The antibody or antigen-binding fragment thereof of claim 1 or 2.

4. a. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:49, and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:50; b. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:51, and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:50; c. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:52 and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:53; d. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 54, and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 55; e. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 56 and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 57; f. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:58 and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:50; g. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:59 and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:60; h. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:61 and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO:50; or i. a heavy chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 62 and a light chain sequence having at least 90%, at least 95%, or at least 98% sequence identity to the amino acid sequence of SEQ ID NO: 63; It consists of: The antibody or antigen-binding fragment thereof according to any one of claims 1 to 3, wherein the CDR regions of the heavy chain sequence and the light chain sequence have the CDR sequences described in claim 1.

5. The format of the antibody or antigen-binding fragment thereof is IgA1, IgA2, IgD, IgE, IgG1, IgG2, IgG3, IgG4, synthetic IgG, IgM, F(ab) 2 , Fv, scFv, IgGACH2, F(ab') 2 , scFvCH3, Fab, VL, VH, scFv4, scFv3, scFv2, dsFv, Fv, scFv-Fc, (scFv) 2 The antibody or antigen-binding fragment thereof according to any one of claims 1 to 4, which is selected from the group consisting of an IgG, a non-depleting IgG, a diabody and a bivalent antibody, and Fc recombinant forms thereof.

6. (i) a humanized antibody or antigen-binding fragment thereof; (ii) an isolated antibody or antigen-binding fragment thereof; and / or (iii) an antibody or an antigen-binding fragment thereof that does not bind to CLDN18.1 The antibody or antigen-binding fragment thereof according to any one of claims 1 to 5,

7. The binding of the antibody or antigen-binding fragment thereof to CLDN18.2 is enhanced compared to a reference antibody; and The reference antibody comprises the heavy chain sequence of SEQ ID NO: 47 and the light chain sequence of SEQ ID NO:

48. The antibody or antigen-binding fragment thereof according to any one of claims 1 to 6,

8. (i) the measured EC50 value of the antibody is at least 10% lower than the EC50 value of a reference antibody; and / or (ii) the maximum MFI value of the antibody measured is at least 10% higher than the maximum MFI value of a reference antibody; and The reference antibody comprises the heavy chain sequence of SEQ ID NO: 47 and the light chain sequence of SEQ ID NO:

48. The antibody or antigen-binding fragment thereof according to claim 7 ,

9. A nucleic acid encoding the antibody or antigen-binding fragment thereof according to any one of claims 1 to 8.

10. A vector comprising the nucleic acid of claim 9.

11. A host cell comprising the nucleic acid of claim 9 or the vector of claim 10.

12. The antibody or antigen-binding fragment thereof of any one of claims 1 to 8, the nucleic acid of claim 9, the vector of claim 10 or the host cell of claim 11 for use in treating a. a subject suffering from a neoplastic disease, b. a subject at risk of developing a neoplastic disease, and / or c. a subject diagnosed with a neoplastic disease.

13. The antibody or antigen-binding fragment thereof of claim 12, wherein the neoplastic disease is selected from the group consisting of pancreatic cancer, gastric cancer, esophageal cancer, ovarian cancer and lung cancer.

Images