Anti-GPRC5d antibody and medical use thereof

Abstract

The present invention relates to an anti-GPRC5D antibody and the medical use thereof. Specifically, the present invention relates to an anti-GPRC5D antibody, a bispecific antibody on the basis of the anti-GPRC5D antibody, and the use thereof in the treatment of cancers.

Description

Anti-GPRC5D antibodies and their medical uses

[0001] This disclosure claims priority to Chinese patent application 202310772444.6 filed on June 28, 2023. Technical Field

[0002] The present disclosure relates to the fields of biology, medicine, and clinical medicine. Specifically, the present disclosure relates to anti-GPRC5D antibodies, bispecific antibodies based on the anti-GPRC5D antibodies, and medical uses thereof. Background Art

[0003] Multiple myeloma (MM) is a hematologic malignancy that damages the bones, immune system, kidneys, and red blood cell count, often leading to extensive bone destruction accompanied by osteolytic lesions, osteopenia, and pathological fractures, a common occurrence in elderly patients. MM ranks second in annual incidence among hematologic malignancies, and its incidence is increasing with the aging population. However, it remains incurable. Currently, targeted therapies for MM include immunomodulatory drugs (thalidomide, lenalidomide, and pomalidomide), proteasome inhibitors (bortezomib, carfilzomib, and ixazomib), and anti-CD38 monoclonal antibodies (daratumumab). BCMA-targeted monoclonal antibodies and CAR-T cell therapies have also shown encouraging results. However, the efficacy of these drugs is limited in relapses associated with low or negative BCMA expression, necessitating an urgent need for new treatment options.

[0004] G protein-coupled receptor C5 family subtype D (GPRC5D) is an orphan receptor first identified in 2001. It is a seven-transmembrane protein. The GPRC5D encoding gene is mapped to chromosome 12p13.3, contains three exons, and spans approximately 9.6 kb (H. Brauner-Osborne et al., Biochimica et Biophysica Actal. 2001, 1518(3): p.237-248). GPRC5D is highly expressed on the surface of primary MM cells, while its expression in normal tissues is limited to the hair follicle region (Shinichi Inoue et al., Journal of Investigative Dermatology. 2004, 122(3): 565-573; Gao Y et al., PLoS ONE. 2016, 11(3): e0151118).

[0005] Studies have shown that GPRC5D has an expression threshold of more than 50% in 65% of MM patients, and it is independent of BCMA expression (Smith et al., SCIENCE TRANSLATIONAL MEDICINE. 2019, eaau7746), suggesting that GPRC5D can still be used as a target for treatment of BCMA-negative cells. The strong selective expression of GPRC5D in MM cells makes this gene and its encoded surface protein a promising marker for monitoring tumor burden and is expected to become a target for anti-myeloma antibodies (Yossi Cohen et al., Hematology. 2013, 18(6): 348-351).

[0006] Autoimmune diseases are characterized by autoantibodies, which are secreted by plasma cells. Autoantibodies provide diagnostic and prognostic criteria, play an essential role in disease pathogenesis, and serve as surrogate markers of disease activity (Martin and Chan, Immunity, 2004, 20(5)). Therefore, effectively depleting autoreactive plasma cells may be the key to curing these diseases.

[0007] Summary of the Invention

[0008] Anti-GPRC5D antibody

[0009] In another aspect, the present disclosure provides an anti-GPRC5D antibody or an antigen-binding fragment thereof, which comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein the GPRC5D-VH and the GPRC5D-VL are selected from any one of the following groups:

[0010] 1) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 41; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 46;

[0011] 2) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 31; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 36;

[0012] 3) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 91; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 96;

[0013] 4) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 21; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 26;

[0014] 5) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 61; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 66;

[0015] 6) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 81; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 86;

[0016] 7) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 1; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 6;

[0017] 8) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 11; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 16;

[0018] 9) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 51; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 56;

[0019] 10) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 71; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 76;

[0020] 11) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 101; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 106;

[0021] 12) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 111; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 116;

[0022] 13) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 121; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 126; and

[0023] 14) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 131; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 136;

[0024] The HCDRs and the LCDRs are identified according to the Kabat, Chothia or IMTG numbering systems.

[0025] In some embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof as described above comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein the GPRC5D-VH and the GPRC5D-VL are selected from any one of the following groups:

[0026] 1) The GPRC5D-VH comprises HCDR1 of SEQ ID NO: 43, HCDR2 of SEQ ID NO: 44, and HCDR3 of SEQ ID NO: 45; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 48, LCDR2 of SEQ ID NO: 49, and LCDR3 of SEQ ID NO: 50;

[0027] 2) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 33, HCDR2 of SEQ ID NO: 34, and HCDR3 of SEQ ID NO: 35; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 38, LCDR2 of SEQ ID NO: 39, and LCDR3 of SEQ ID NO: 40;

[0028] 3) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 93, HCDR2 of SEQ ID NO: 94, and HCDR3 of SEQ ID NO: 95; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 98, LCDR2 of SEQ ID NO: 99, and LCDR3 of SEQ ID NO: 100;

[0029] 4) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 23, HCDR2 of SEQ ID NO: 24, and HCDR3 of SEQ ID NO: 25; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 28, LCDR2 of SEQ ID NO: 29, and LCDR3 of SEQ ID NO: 30;

[0030] 5) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 63, HCDR2 of SEQ ID NO: 64, and HCDR3 of SEQ ID NO: 65; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 68, LCDR2 of SEQ ID NO: 69, and LCDR3 of SEQ ID NO: 70;

[0031] 6) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 83, HCDR2 of SEQ ID NO: 84, and HCDR3 of SEQ ID NO: 85; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 88, LCDR2 of SEQ ID NO: 89, and LCDR3 of SEQ ID NO: 90;

[0032] 7) The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 3, HCDR2 shown in SEQ ID NO: 4, and HCDR3 shown in SEQ ID NO: 5; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 8, LCDR2 shown in SEQ ID NO: 9, and LCDR3 shown in SEQ ID NO: 10;

[0033] 8) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 13, HCDR2 of SEQ ID NO: 14, and HCDR3 of SEQ ID NO: 15; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 18, LCDR2 of SEQ ID NO: 19, and LCDR3 of SEQ ID NO: 20;

[0034] 9) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 53, HCDR2 of SEQ ID NO: 54, and HCDR3 of SEQ ID NO: 55; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 58, LCDR2 of SEQ ID NO: 59, and LCDR3 of SEQ ID NO: 60;

[0035] 10) The GPRC5D-VH comprises HCDR1 of SEQ ID NO: 73, HCDR2 of SEQ ID NO: 74, and HCDR3 of SEQ ID NO: 75; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 78, LCDR2 of SEQ ID NO: 79, and LCDR3 of SEQ ID NO: 80;

[0036] 11) The GPRC5D-VH comprises HCDR1 of SEQ ID NO: 103, HCDR2 of SEQ ID NO: 104, and HCDR3 of SEQ ID NO: 105; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 108, LCDR2 of SEQ ID NO: 109, and LCDR3 of SEQ ID NO: 110;

[0037] 12) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 113, HCDR2 of SEQ ID NO: 114, and HCDR3 of SEQ ID NO: 115; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 118, LCDR2 of SEQ ID NO: 119, and LCDR3 of SEQ ID NO: 120;

[0038] 13) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 123, HCDR2 shown in SEQ ID NO: 124, and HCDR3 shown in SEQ ID NO: 125; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 128, LCDR2 shown in SEQ ID NO: 129, and LCDR3 shown in SEQ ID NO: 130; and

[0039] 14) The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 133, HCDR2 shown in SEQ ID NO: 134, and HCDR3 shown in SEQ ID NO: 135; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 138, LCDR2 shown in SEQ ID NO: 139, and LCDR3 shown in SEQ ID NO: 140.

[0040] In some embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof as described above comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0041] The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 43, HCDR2 shown in SEQ ID NO: 44, and HCDR3 shown in SEQ ID NO: 45; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 48, LCDR2 shown in SEQ ID NO: 49, and LCDR3 shown in SEQ ID NO: 50.

[0042] In some embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof as described above comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0043] The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 33, HCDR2 shown in SEQ ID NO: 34, and HCDR3 shown in SEQ ID NO: 35; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 38, LCDR2 shown in SEQ ID NO: 39, and LCDR3 shown in SEQ ID NO: 40.

[0044] In some embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof as described above comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0045] The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 93, HCDR2 shown in SEQ ID NO: 94, and HCDR3 shown in SEQ ID NO: 95; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 98, LCDR2 shown in SEQ ID NO: 99, and LCDR3 shown in SEQ ID NO: 100.

[0046] In some specific embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof according to any of the preceding items comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein the GPRC5D-VH and the GPRC5D-VL are selected from any one of the following groups:

[0047] 1) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:41, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:41, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:46, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:46;

[0048] 2) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:31, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:31, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:36, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:36;

[0049] 3) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:91, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:91, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:96, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:96;

[0050] 4) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:21, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:21, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:26, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:26;

[0051] 5) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:61, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:61, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:66, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:66;

[0052] 6) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:81, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:81, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:86, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:86;

[0053] 7) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO: 1 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 1, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO: 6 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 6;

[0054] 8) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 11, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 11, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 16, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 16;

[0055] 9) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:51, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:51, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:56, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:56;

[0056] 10) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:71, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:71, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:76, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:76;

[0057] 11) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:101, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:101, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:106, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:106;

[0058] 12) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 111, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 111, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 116, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 116;

[0059] 13) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 121, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 121, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 126, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 126; and

[0060] 14) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 131 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 131, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 136 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 136.

[0061] In some specific embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof as described in any of the preceding items, wherein:

[0062] GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:41 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:41, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:46 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:46.

[0063] In some specific embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof as described in any of the preceding items, wherein:

[0064] GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:31 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:31, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:36 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:36.

[0065] In some specific embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof as described in any of the preceding items, wherein:

[0066] GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:91 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:91, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:96 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:96.

[0067] In this context, "at least 85%" means at least 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100%, or a range between any two of the foregoing values, which can be an integer or a decimal.

[0068] In some embodiments, the anti-GPRC5D antibody or antigen-binding fragment thereof as described in any of the preceding items is a humanized antibody or antigen-binding fragment thereof, a fully human antibody or antigen-binding fragment thereof, or a chimeric antibody or antigen-binding fragment thereof.

[0069] In some embodiments, in the anti-GPRC5D antibody or antigen-binding fragment thereof according to any of the preceding items, the heavy chain variable region GPRC5D-VH and / or the light chain variable region GPRC5D-VL are humanized.

[0070] In some embodiments, the antigen-binding fragment of any of the aforementioned anti-GPRC5D antibodies is selected from any one of the following: Fab, scFv, Fv, Fab', F(ab')2, single domain antibody, scFab, linear antibody, and multispecific antibody.

[0071] In some embodiments, any of the aforementioned anti-GPRC5D antibodies or antigen-binding fragments thereof further comprises a heavy chain constant region and a light chain constant region. In some embodiments, the heavy chain constant region is selected from human IgG1, human IgG2, human IgG3, and human IgG4, and the light chain constant region is selected from lambda and kappa light chain constant regions. In some embodiments, the heavy chain constant region is a human IgG1 heavy chain constant region, and the light chain constant region is a kappa light chain constant region. In some embodiments, the heavy chain constant region comprises the amino acid sequence of SEQ ID NO: 143, and the light chain constant region comprises the amino acid sequence of SEQ ID NO: 144.

[0072] In some embodiments, any of the aforementioned anti-GPRC5D antibodies or antigen-binding fragments thereof further comprises an Fc.

[0073] In some specific embodiments, any of the aforementioned anti-GPRC5D antibodies comprises human IgG1 Fc, human IgG2 Fc, human IgG3 Fc, or human IgG4 Fc; preferably human IgG1 Fc.

[0074] In some specific embodiments, the anti-GPRC5D antibody comprises the heavy chain set forth in SEQ ID NO: 149, or a sequence at least 85% identical thereto, and the light chain set forth in SEQ ID NO: 150, or a sequence at least 85% identical thereto.

[0075] In other specific embodiments, the anti-GPRC5D antibody comprises:

[0076] The heavy chain comprises the amino acid sequence set forth in SEQ ID NO: 147 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 147, and

[0077] The light chain comprises the amino acid sequence set forth in SEQ ID NO: 148 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 148.

[0078] In other specific embodiments, the anti-GPRC5D antibody comprises:

[0079] The heavy chain comprises the amino acid sequence set forth in SEQ ID NO: 155 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 155, and

[0080] The light chain comprises the amino acid sequence set forth in SEQ ID NO: 156 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 156.

[0081] In other specific embodiments, the anti-GPRC5D antibody comprises:

[0082] The heavy chain comprises the amino acid sequence set forth in SEQ ID NO: 145 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 145, and

[0083] The light chain comprises the amino acid sequence set forth in SEQ ID NO: 146 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 146.

[0084] In other specific embodiments, the anti-GPRC5D antibody comprises:

[0085] The heavy chain comprises the amino acid sequence shown in SEQ ID NO: 151 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 151, and

[0086] The light chain comprises the amino acid sequence set forth in SEQ ID NO: 152 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 152.

[0087] In other specific embodiments, the anti-GPRC5D antibody comprises:

[0088] The heavy chain comprises the amino acid sequence shown in SEQ ID NO: 153 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 153, and

[0089] The light chain comprises the amino acid sequence set forth in SEQ ID NO: 154 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 154.

[0090] In some specific embodiments, the anti-GPRC5D antibody comprises:

[0091] The heavy chain comprises the amino acid sequence set forth in SEQ ID NO: 149 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 149, and

[0092] The light chain comprises the amino acid sequence shown in SEQ ID NO: 150 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 150.

[0093] In other specific embodiments, the anti-GPRC5D antibody comprises the heavy chain set forth in SEQ ID NO:145, and the light chain set forth in SEQ ID NO:146.

[0094] In other specific embodiments, the anti-GPRC5D antibody comprises the heavy chain set forth in SEQ ID NO:147, and the light chain set forth in SEQ ID NO:148.

[0095] In other specific embodiments, the anti-GPRC5D antibody comprises the heavy chain set forth in SEQ ID NO:149, and the light chain set forth in SEQ ID NO:150.

[0096] In other specific embodiments, the anti-GPRC5D antibody comprises the heavy chain set forth in SEQ ID NO:151, and the light chain set forth in SEQ ID NO:152.

[0097] In other specific embodiments, the anti-GPRC5D antibody comprises the heavy chain set forth in SEQ ID NO:153, and the light chain set forth in SEQ ID NO:154.

[0098] In other specific embodiments, the anti-GPRC5D antibody comprises the heavy chain set forth in SEQ ID NO:155, and the light chain set forth in SEQ ID NO:156.

[0099] In some specific embodiments, the anti-GPRC5D antibodies or antigen-binding fragments thereof disclosed herein have an EC no greater than 0.4, 0.39, 0.38, 0.37, 0.36, 0.35, 0.34, 0.33, 0.32, 0.31, 0.30, 0.29, 0.28, 0.27, or 0.26 nM. 50 , binds to cells expressing human GPRC5D.

[0100] Bispecific antibodies

[0101] The present disclosure provides a bispecific antibody comprising:

[0102] at least one first binding moiety that specifically binds GPRC5D; and

[0103] At least one second binding moiety that specifically binds CD3.

[0104] In one aspect, the present disclosure provides a bispecific antibody comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein the GPRC5D-VH and the GPRC5D-VL are selected from any one of the following groups:

[0105] 1) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 41; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 46;

[0106] 2) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 31; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 36;

[0107] 3) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 91; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 96;

[0108] 4) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 21; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 26;

[0109] 5) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 61; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 66;

[0110] 6) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 81; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 86;

[0111] 7) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 1; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 6;

[0112] 8) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 11; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 16;

[0113] 9) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 51; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 56;

[0114] 10) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 71; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 76;

[0115] 11) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 101; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 106;

[0116] 12) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 111; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 116;

[0117] 13) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 121; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 126; and

[0118] 14) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 131; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 136;

[0119] The amino acid sequences of the HCDR and the LCDR are determined according to the Kabat, Chothia or IMTG numbering systems.

[0120] In some embodiments, a bispecific antibody is provided, comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein the GPRC5D-VH and the GPRC5D-VL are selected from any one of the following groups:

[0121] 1) The GPRC5D-VH comprises HCDR1 of SEQ ID NO: 43, HCDR2 of SEQ ID NO: 44, and HCDR3 of SEQ ID NO: 45; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 48, LCDR2 of SEQ ID NO: 49, and LCDR3 of SEQ ID NO: 50;

[0122] 2) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 33, HCDR2 of SEQ ID NO: 34, and HCDR3 of SEQ ID NO: 35; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 38, LCDR2 of SEQ ID NO: 39, and LCDR3 of SEQ ID NO: 40;

[0123] 3) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 93, HCDR2 of SEQ ID NO: 94, and HCDR3 of SEQ ID NO: 95; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 98, LCDR2 of SEQ ID NO: 99, and LCDR3 of SEQ ID NO: 100;

[0124] 4) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 23, HCDR2 of SEQ ID NO: 24, and HCDR3 of SEQ ID NO: 25; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 28, LCDR2 of SEQ ID NO: 29, and LCDR3 of SEQ ID NO: 30;

[0125] 5) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 63, HCDR2 of SEQ ID NO: 64, and HCDR3 of SEQ ID NO: 65; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 68, LCDR2 of SEQ ID NO: 69, and LCDR3 of SEQ ID NO: 70;

[0126] 6) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 83, HCDR2 of SEQ ID NO: 84, and HCDR3 of SEQ ID NO: 85; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 88, LCDR2 of SEQ ID NO: 89, and LCDR3 of SEQ ID NO: 90;

[0127] 7) The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 3, HCDR2 shown in SEQ ID NO: 4, and HCDR3 shown in SEQ ID NO: 5; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 8, LCDR2 shown in SEQ ID NO: 9, and LCDR3 shown in SEQ ID NO: 10;

[0128] 8) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 13, HCDR2 of SEQ ID NO: 14, and HCDR3 of SEQ ID NO: 15; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 18, LCDR2 of SEQ ID NO: 19, and LCDR3 of SEQ ID NO: 20;

[0129] 9) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 53, HCDR2 of SEQ ID NO: 54, and HCDR3 of SEQ ID NO: 55; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 58, LCDR2 of SEQ ID NO: 59, and LCDR3 of SEQ ID NO: 60;

[0130] 10) The GPRC5D-VH comprises HCDR1 of SEQ ID NO: 73, HCDR2 of SEQ ID NO: 74, and HCDR3 of SEQ ID NO: 75; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 78, LCDR2 of SEQ ID NO: 79, and LCDR3 of SEQ ID NO: 80;

[0131] 11) The GPRC5D-VH comprises HCDR1 of SEQ ID NO: 103, HCDR2 of SEQ ID NO: 104, and HCDR3 of SEQ ID NO: 105; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 108, LCDR2 of SEQ ID NO: 109, and LCDR3 of SEQ ID NO: 110;

[0132] 12) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 113, HCDR2 of SEQ ID NO: 114, and HCDR3 of SEQ ID NO: 115; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 118, LCDR2 of SEQ ID NO: 119, and LCDR3 of SEQ ID NO: 120;

[0133] 13) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 123, HCDR2 shown in SEQ ID NO: 124, and HCDR3 shown in SEQ ID NO: 125; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 128, LCDR2 shown in SEQ ID NO: 129, and LCDR3 shown in SEQ ID NO: 130; and

[0134] 14) The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 133, HCDR2 shown in SEQ ID NO: 134, and HCDR3 shown in SEQ ID NO: 135; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 138, LCDR2 shown in SEQ ID NO: 139, and LCDR3 shown in SEQ ID NO: 140.

[0135] In some specific embodiments, a bispecific antibody is provided, comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0136] The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 43, HCDR2 shown in SEQ ID NO: 44, and HCDR3 shown in SEQ ID NO: 45; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 48, LCDR2 shown in SEQ ID NO: 49, and LCDR3 shown in SEQ ID NO: 50.

[0137] In some specific embodiments, a bispecific antibody is provided, comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0138] The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 33, HCDR2 shown in SEQ ID NO: 34, and HCDR3 shown in SEQ ID NO: 35; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 38, LCDR2 shown in SEQ ID NO: 39, and LCDR3 shown in SEQ ID NO: 40.

[0139] In some specific embodiments, a bispecific antibody is provided, comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0140] The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 93, HCDR2 shown in SEQ ID NO: 94, and HCDR3 shown in SEQ ID NO: 95; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 98, LCDR2 shown in SEQ ID NO: 99, and LCDR3 shown in SEQ ID NO: 100.

[0141] In some specific embodiments, a bispecific antibody is provided, comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0142] 1) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:41, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:41, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:46, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:46;

[0143] 2) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:31, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:31, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:36, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:36;

[0144] 3) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:91, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:91, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:96, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:96;

[0145] 4) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:21, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:21, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:26, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:26;

[0146] 5) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:61, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:61, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:66, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:66;

[0147] 6) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:81, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:81, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:86, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:86;

[0148] 7) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO: 1 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 1, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO: 6 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 6;

[0149] 8) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 11, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 11, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 16, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 16;

[0150] 9) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 51, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 51, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 56, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 56;

[0151] 10) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:71, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:71, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:76, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:76;

[0152] 11) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO:101, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:101, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO:106, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:106;

[0153] 12) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 111, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 111, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 116, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 116;

[0154] 13) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 121, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 121, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 126, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 126; and

[0155] 14) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 131 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 131, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 136 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 136.

[0156] In some specific embodiments, a bispecific antibody is provided, comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0157] GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:41 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:41, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:46 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:46.

[0158] In some specific embodiments, a bispecific antibody is provided, comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0159] GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:31 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:31, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:36 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:36.

[0160] In some specific embodiments, a bispecific antibody is provided, comprising at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein:

[0161] GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:91 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:91, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:96 or an amino acid sequence having at least 85% sequence identity to SEQ ID NO:96.

[0162] In this context, "at least 85%" means at least 85, 86, 87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100%, or a range between any two of the foregoing values, which can be an integer or a decimal.

[0163] In some specific embodiments, any of the aforementioned bispecific antibodies, wherein the second binding moiety that specifically binds to CD3 comprises a heavy chain variable region CD3-VH and a light chain variable region CD3-VL, wherein,

[0164] The CD3-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 202; the CD3-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 203; the HCDRs and LCDRs are identified according to the Kabat, Chothia, or IMTG numbering systems.

[0165] In some specific embodiments, any of the aforementioned bispecific antibodies, wherein the second binding portion that specifically binds to CD3 comprises a heavy chain variable region CD3-VH and a light chain variable region CD3-VL, wherein,

[0166] The CD3-VH comprises HCDR1 shown in SEQ ID NO: 204, HCDR2 shown in SEQ ID NO: 205, and HCDR3 shown in SEQ ID NO: 206; and the CD3-VL comprises LCDR1 shown in SEQ ID NO: 207, LCDR2 shown in SEQ ID NO: 208, and LCDR3 shown in SEQ ID NO: 209.

[0167] In some specific embodiments, any of the aforementioned bispecific antibodies, wherein the second binding portion that specifically binds to CD3 comprises the heavy chain variable region CD3-VH shown in SEQ ID NO: 202, and the light chain variable region CD3-VL shown in SEQ ID NO: 203.

[0168] In some embodiments, the heavy chain variable region GPRC5D-VH and / or the light chain variable region GPRC5D-VL are humanized.

[0169] In some specific embodiments, the bispecific antibody comprises at least one first binding moiety that specifically binds GPRC5D and at least one second binding moiety that specifically binds CD3, wherein the first binding moiety comprises GPRC5D-VH set forth in SEQ ID NO:41 and GPRC5D-VL set forth in SEQ ID NO:46; the second binding moiety comprises the heavy chain variable region CD3-VH set forth in SEQ ID NO:202, and the light chain variable region CD3-VL set forth in SEQ ID NO:203.

[0170] In other specific embodiments, the bispecific antibody comprises at least one first binding moiety that specifically binds to GPRC5D and at least one second binding moiety that specifically binds to CD3, wherein the first binding moiety comprises GPRC5D-VH set forth in SEQ ID NO: 31 and GPRC5D-VL set forth in SEQ ID NO: 36; and the second binding moiety comprises the heavy chain variable region CD3-VH set forth in SEQ ID NO: 202, and the light chain variable region CD3-VL set forth in SEQ ID NO: 203.

[0171] In other specific embodiments, the bispecific antibody comprises at least one first binding moiety that specifically binds GPRC5D and at least one second binding moiety that specifically binds CD3, wherein the first binding moiety comprises GPRC5D-VH set forth in SEQ ID NO: 91 and GPRC5D-VL set forth in SEQ ID NO: 96; and the second binding moiety comprises the heavy chain variable region CD3-VH set forth in SEQ ID NO: 202, and the light chain variable region CD3-VL set forth in SEQ ID NO: 203.

[0172] In some embodiments, the bispecific antibody as described in any of the preceding items, wherein the bispecific antibody further comprises an Fc region, wherein the Fc region comprises two subunits (a first subunit Fc1 and a second subunit Fc2).

[0173] It should be understood that the ordinal numbers "first", "second", "Formula a", "Formula b", "1)", "2)", etc. in the present disclosure are only used to distinguish different technical features, elements, components, and steps, and are not intended to limit the level, sequence, or quantity.

[0174] In some embodiments, the two subunits are a first subunit Fc1 and a second subunit Fc2, which have identical or different amino acid sequences.

[0175] In some embodiments, the first subunit Fc1 and the second subunit Fc2 each independently have one or more amino acid substitutions that reduce Fc region homodimerization.

[0176] In some embodiments, the first subunit Fc1 and the second subunit Fc2 each independently have a knob-in-hole amino acid substitution.

[0177] In some embodiments, the first subunit Fc1 comprises a hole structure according to the knob-in-hole KIH technique; and the second subunit Fc2 comprises a knob structure according to the knob-in-hole KIH technique.

[0178] In other embodiments, the second subunit Fc2 comprises a hole structure according to the knob-in-hole KIH technique; and the first subunit Fc1 comprises a knob structure according to the knob-in-hole KIH technique.

[0179] In some embodiments, the amino acid at position 366 of the first subunit Fc1 is S, the amino acid at position 368 is A, and the amino acid at position 407 is V, and the amino acid at position 366 of the second subunit Fc2 is W; numbering is according to the EU index. In some embodiments, the Fc region is an IgG Fc region, particularly an IgG1 Fc region.

[0180] In some embodiments, the Fc region is a human IgG1 Fc region, and the amino acids at positions 234 and 235 are A, numbering according to the EU index.

[0181] In some embodiments, the Fc1 has the amino acid sequence shown in SEQ ID NO: 199, and the Fc2 has the amino acid sequence shown in SEQ ID NO: 197 or 198.

[0182] In some embodiments, the bispecific antibody of any of the preceding items comprises at least one first binding moiety that specifically binds to GPRC5D, at least one second binding moiety that specifically binds to CD3, and an Fc region.

[0183] In some embodiments, the first binding moiety that specifically binds GPRC5D is a Fab; and the second binding moiety that specifically binds CD3 is a scFv.

[0184] In other embodiments, the first binding moiety that specifically binds GPRC5D is a scFv; and the second binding moiety that specifically binds CD3 is a Fab.

[0185] In other embodiments, the first binding moiety that specifically binds GPRC5D is a Fab, and the second binding moiety that specifically binds CD3 is a Fab.

[0186] In some embodiments, the first binding moiety that specifically binds GPRC5D, the second binding moiety that specifically binds CD3, and one subunit of the Fc region are linked directly or through a linker in an N-terminus to C-terminus order.

[0187] In some embodiments, the second binding moiety that specifically binds CD3, the first binding moiety that specifically binds GPRC5D, and one subunit of the Fc region are linked directly or through a linker in an N-terminus to C-terminus order.

[0188] In some embodiments, the first binding moiety that specifically binds to GPRC5D, a subunit of the Fc region, and the second binding moiety that specifically binds to CD3 are linked directly or through a linker in an N-terminal to C-terminal order.

[0189] In some embodiments, the second binding moiety that specifically binds to CD3, a subunit of the Fc region, and the first binding moiety that specifically binds to GPRC5D are linked directly or through a linker in the order of N-terminus to C-terminus.

[0190] In some embodiments, the bispecific antibody as described in any of the preceding items, wherein the bispecific antibody comprises: a first chain shown in formula a, a second chain shown in formula b, and a third chain shown in formula c;

[0191] Formula a: [GPRC5D-VH]-[CH1]-[Fc1];

[0192] Formula b: [GPRC5D-VL]-[CL];

[0193] Formula c: [CD3-VL]-[Linker]-[CD3-VH]-[Fc2]; wherein:

[0194] The first subunit and the second subunit are interchangeable;

[0195] The structures shown in formula a, formula b and formula c are arranged from the N-terminus to the C-terminus.

[0196] In some embodiments, the bispecific antibody as described in any of the preceding items, wherein the bispecific antibody comprises a first chain shown in formula a, a second chain shown in formula b, and a third chain shown in formula c;

[0197] In other embodiments, the bispecific antibody as described in any of the preceding items, wherein the bispecific antibody comprises: a first chain shown in formula a, a second chain shown in formula b, a third chain shown in formula d, and a fourth chain shown in formula e;

[0198] Formula a: [GPRC5D-VH]-[CH1]-[Fc1];

[0199] Formula b: [GPRC5D-VL]-[CL];

[0200] Formula d: [CD3-VH]-[CH1]-[Fc2];

[0201] Formula e: [CD3-VL]-[CL]; wherein:

[0202] The first subunit and the second subunit are interchangeable;

[0203] The structures shown in Formula a, Formula b, Formula d and Formula e are arranged from the N-terminus to the C-terminus.

[0204] In some embodiments, the bispecific antibody as described in any of the preceding items, wherein the bispecific antibody comprises a first chain shown in formula a, a second chain shown in formula b, a third chain shown in formula d, and a fourth chain shown in formula e.

[0205] In some embodiments, the bispecific antibody of any of the preceding items, wherein the GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 41, and the GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 46; and

[0206] The CD3-VH comprises the amino acid sequence of SEQ ID NO: 202, and the CD3-VL comprises the amino acid sequence of SEQ ID NO: 203.

[0207] In some embodiments, the bispecific antibody of any of the preceding items, wherein the GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 31, and the GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 36; and

[0208] The CD3-VH comprises the amino acid sequence of SEQ ID NO: 202, and the CD3-VL comprises the amino acid sequence of SEQ ID NO: 203.

[0209] In some embodiments, the bispecific antibody of any of the preceding items, wherein the GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 91, and the GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 96; and

[0210] The CD3-VH comprises the amino acid sequence of SEQ ID NO: 202, and the CD3-VL comprises the amino acid sequence of SEQ ID NO: 203. In some embodiments, the linker is a peptide linker, preferably a flexible peptide linker. In some embodiments, the peptide linker is 3-15 amino acid residues in length. In some embodiments, the peptide linker has a structure of (GGGGS)n (SEQ ID NO: 217), wherein n is an integer from 1 to 8. In some embodiments, n is 2, 3, 4, 5, or 6.

[0211] In some specific embodiments, the peptide linker is as shown in SEQ ID NO: 200.

[0212] In some embodiments, the bispecific antibody of any of the preceding items, wherein the CH1 is the CH1 sequence of IgG. In some embodiments, the CH1 is the CH1 of IgG1. In some embodiments, the CH1 comprises the amino acid sequence of SEQ ID NO: 201.

[0213] In some embodiments, the antigen-binding molecule described in any of the preceding items, wherein the CL is an antibody light chain constant region. In some embodiments, the antigen-binding molecule described in any of the preceding items, wherein the CL is a kappa or lamada light chain constant region. In some embodiments, wherein the CL comprises the amino acid sequence of SEQ ID NO: 144.

[0214] In some specific embodiments, the bispecific antibody comprises: a first chain shown in SEQ ID NO: 161, a second chain shown in SEQ ID NO: 163, and a third chain shown in SEQ ID NO: 159.

[0215] In some specific embodiments, the bispecific antibody comprises: a first chain shown in SEQ ID NO: 165, a second chain shown in SEQ ID NO: 167, and a third chain shown in SEQ ID NO: 159.

[0216] In some specific embodiments, the bispecific antibody comprises: a first chain shown in SEQ ID NO: 169, a second chain shown in SEQ ID NO: 171, and a third chain shown in SEQ ID NO: 159.

[0217] In some specific embodiments, the bispecific antibody comprises: a first chain shown in SEQ ID NO: 173, a second chain shown in SEQ ID NO: 175, a third chain shown in SEQ ID NO: 177, and a fourth chain shown in SEQ ID NO: 179.

[0218] In some specific embodiments, the bispecific antibody comprises: a first chain shown in SEQ ID NO: 161, a second chain shown in SEQ ID NO: 163, and a third chain shown in SEQ ID NO: 159.

[0219] In some specific embodiments, the bispecific antibody comprises: a first chain shown in SEQ ID NO: 165, a second chain shown in SEQ ID NO: 167, and a third chain shown in SEQ ID NO: 159.

[0220] In some specific embodiments, the bispecific antibody comprises: a first chain shown in SEQ ID NO: 169, a second chain shown in SEQ ID NO: 171, and a third chain shown in SEQ ID NO: 159.

[0221] In some specific embodiments, the bispecific antibody comprises: a first chain shown in SEQ ID NO: 173, a second chain shown in SEQ ID NO: 175, a third chain shown in SEQ ID NO: 177, and a fourth chain shown in SEQ ID NO: 179.

[0222] In some specific embodiments, the bispecific antibodies of the present disclosure have an EC no greater than 4, 3.9, 3.8, 3.7, 3.6, 3.5, 3.4, 3.3, 3.2, 3.1, 3.0, 2.9, 2.8, 2.7, 2.6, 2.5, 2.49, 2.48, 2.47, 2.46, 2.45, or 2.44 nM. 50 , combined with cells expressing human GPRC5D; preferably HEK293T cells expressing hGPRC5D.

[0223] Pharmaceutical composition

[0224] In another aspect, the present disclosure provides a pharmaceutical composition comprising:

[0225] A preventively or therapeutically effective amount of any of the aforementioned bispecific antibodies or anti-GPRC5D antibodies or antigen-binding fragments thereof, and one or more pharmaceutically acceptable carriers, diluents, buffers or excipients.

[0226] Isolated nucleic acids

[0227] In another aspect, the present disclosure also provides an isolated nucleic acid encoding any of the aforementioned bispecific antibodies or anti-GPRC5D antibodies or antigen-binding fragments thereof.

[0228] In some embodiments, the nucleic acid is selected from any one of the following groups:

[0229] 1) The nucleic acid comprises the sequences shown in SEQ ID NO: 42 and SEQ ID NO: 47;

[0230] 2) the nucleic acid comprises the sequences shown in SEQ ID NO: 32 and SEQ ID NO: 37;

[0231] 3) the nucleic acid comprises the sequences shown in SEQ ID NO: 92 and SEQ ID NO: 97;

[0232] 4) the nucleic acid comprises the sequences shown in SEQ ID NO: 22 and SEQ ID NO: 27;

[0233] 5) The nucleic acid comprises the sequences shown in SEQ ID NO: 62 and SEQ ID NO: 67;

[0234] 6) The nucleic acid comprises the sequences shown in SEQ ID NO: 82 and SEQ ID NO: 87;

[0235] 7) The nucleic acid comprises the sequences shown in SEQ ID NO: 2 and SEQ ID NO: 7;

[0236] 8) The nucleic acid comprises the sequences shown in SEQ ID NO: 12 and SEQ ID NO: 17;

[0237] 9) The nucleic acid comprises the sequences shown in SEQ ID NO: 52 and SEQ ID NO: 57;

[0238] 10) The nucleic acid comprises the sequences shown in SEQ ID NO: 72 and SEQ ID NO: 77;

[0239] 11) The nucleic acid comprises the sequences shown in SEQ ID NO: 102 and SEQ ID NO: 107;

[0240] 12) The nucleic acid comprises the sequences shown in SEQ ID NO: 112 and SEQ ID NO: 117;

[0241] 13) The nucleic acid comprises the sequences shown in SEQ ID NO: 122 and SEQ ID NO: 127; and

[0242] 14) The nucleic acid comprises the sequences shown in SEQ ID NO: 132 and SEQ ID NO: 137.

[0243] In some embodiments, the nucleic acid is selected from any one of the following groups:

[0244] 1) The nucleic acid comprises the sequences shown in SEQ ID NO: 160, SEQ ID NO: 166 and SEQ ID NO: 168;

[0245] 2) the nucleic acid comprises the sequences shown in SEQ ID NO: 160, SEQ ID NO: 162 and SEQ ID NO: 164;

[0246] 3) the nucleic acid comprises the sequences shown in SEQ ID NO: 160, SEQ ID NO: 170 and SEQ ID NO: 172; and

[0247] 4) The nucleic acid comprises the sequences shown in SEQ ID NO: 174, SEQ ID NO: 176, SEQ ID NO: 178 and SEQ ID NO: 180.

[0248] It should be understood that even though the present disclosure provides specific nucleotide sequence examples, the nucleotide sequences capable of "encoding the bispecific antibodies or anti-GPRC5D antibodies or antigen-binding fragments thereof of the present disclosure" are not limited to these specific sequences, because equivalent nucleotide sequences can be used to encode the same amino acid sequence depending on the codon preference and codon degeneracy of the expression host.

[0249] In another aspect, the present disclosure further provides a host cell comprising the aforementioned nucleic acid or the aforementioned vector, or for expressing the bispecific antibody or anti-GPRC5D antibody or antigen-binding fragment thereof of the present disclosure.

[0250] Prevention or treatment methods

[0251] In another aspect, the present disclosure also provides a method for treating a disease, comprising administering to a subject a preventively or therapeutically effective amount of any of the aforementioned bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof, nucleic acids, or pharmaceutical compositions.

[0252] In some embodiments, the disease is cancer or an autoimmune disease.

[0253] In some embodiments, the disease is selected from the group consisting of: multiple myeloma, Waldstrom's macroglobulinemia, endometrial cancer, ovarian cancer, lung cancer, gastric cancer, prostate cancer, kidney cancer, liver cancer, pancreatic cancer, colorectal cancer, esophageal cancer, bladder cancer, cervical cancer, blood cancer, lymphoma, and malignant melanoma.

[0254] In some embodiments, the disease is associated with abnormal expression of GPRC5D. In some embodiments, cancer cells of the cancer express GPRC5D protein.

[0255] In some embodiments, the cancer is a hematological cancer.

[0256] In some embodiments, the cancer is a solid tumor.

[0257] In another aspect, the present disclosure also provides a method for preventing or treating multiple myeloma, comprising administering to a subject a preventively or therapeutically effective amount of any of the aforementioned bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof, nucleic acids, or pharmaceutical compositions.

[0258] use

[0259] In another aspect, the present disclosure further provides use of any of the aforementioned bispecific antibodies, anti-GPRC5D antibodies or antigen-binding fragments thereof, nucleic acids, or pharmaceutical compositions in the preparation of drugs for treating or preventing diseases.

[0260] In some embodiments, the disease is cancer or an autoimmune disease.

[0261] In some embodiments, the disease is selected from the group consisting of: multiple myeloma, Waldstrom's macroglobulinemia, endometrial cancer, ovarian cancer, lung cancer, gastric cancer, prostate cancer, kidney cancer, liver cancer, pancreatic cancer, colorectal cancer, esophageal cancer, bladder cancer, cervical cancer, blood cancer, lymphoma, and malignant melanoma.

[0262] In some embodiments, the disease is associated with abnormal expression of GPRC5D protein.

[0263] In some embodiments, the cancer cells of the cancer express GPRC5D protein.

[0264] In some embodiments, the cancer is a hematological cancer.

[0265] In some embodiments, the cancer is a solid tumor.

[0266] In some embodiments, the disease is multiple myeloma.

[0267] In another aspect, the present disclosure further provides any of the aforementioned bispecific antibodies, anti-GPRC5D antibodies or antigen-binding fragments thereof, nucleic acids, or pharmaceutical compositions for use as a medicament.

[0268] In some embodiments, the medicament is for treating a disease.

[0269] In some embodiments, the disease is cancer or an autoimmune disease. In some embodiments, the disease is selected from the group consisting of: multiple myeloma, Waldstrom's macroglobulinemia, endometrial cancer, ovarian cancer, lung cancer, gastric cancer, prostate cancer, kidney cancer, liver cancer, pancreatic cancer, colorectal cancer, esophageal cancer, bladder cancer, cervical cancer, blood cancer, lymphoma, and malignant melanoma.

[0270] In some embodiments, the disease is associated with abnormal expression of GPRC5D protein.

[0271] In some embodiments, the cancer cells of the cancer express GPRC5D protein.

[0272] In some embodiments, the cancer is a hematological cancer.

[0273] In some embodiments, the cancer is a solid tumor.

[0274] In some embodiments, the medicament is for treating multiple myeloma.

[0275] In another aspect, the bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof disclosed herein are used in immunoassays. The immunoassay comprises contacting a biological sample with the bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof disclosed herein to detect cancer cells or GPRC5D expression in a biological sample from a patient. Typically, the bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof disclosed herein can be coupled to a fluorescent label or other label.

[0276] Reagents / Kits

[0277] In another aspect, the present disclosure further provides a drug kit comprising at least one container, wherein each container independently comprises: any one of the aforementioned bispecific antibodies, anti-GPRC5D antibodies or antigen-binding fragments thereof, nucleic acids, or pharmaceutical compositions of the present disclosure.

[0278] For diagnostic or research use, the kit comprises one or more of the following components: assay reagents, buffers, and the antibodies of the disclosure.

[0279] Additionally, these reagents / kits may include instructions. BRIEF DESCRIPTION OF THE DRAWINGS

[0280] Figure 1 shows the results of binding activity assays of anti-GPRC5D antibodies produced by hybridomas to GPRC5D from different species. WT represents wild-type HEK293T cells.

[0281] FIG2 shows the results of the binding activity assay of the anti-GPRC5D antibody produced by the hybridoma to human GPRC5A, GPRC5B and GPRC5C.

[0282] FIG3 shows the binding activity test results of the anti-GPRC5D×CD3 bispecific antibodies Bs71D8, Bs80A8, Bs155C2 and the positive control BM03 to HEK293T_hGPRC5D cells overexpressing human_GPRC5D.

[0283] FIG4 shows the results of binding activity detection of the anti-GPRC5D×CD3 bispecific antibodies Bs80A8, 80A8KIH and the positive control DuobodyBM to HEK293T_hGPRC5D cells overexpressing human_GPRC5D.

[0284] FIG5 shows the specific activation of human T cells by the anti-GPRC5D×CD3 bispecific antibodies Bs71D8, Bs80A8, Bs155C2 and the positive control BM03 in the presence of MM.1R cells.

[0285] FIG6 shows the specific activation of human T cells by the anti-GPRC5D×CD3 bispecific antibody Bs80A8 and the positive control DuobodyBM in the presence of MM.1R cells.

[0286] FIG7 shows the results of the T cell cytotoxicity assay induced by the anti-GPRC5D×CD3 bispecific antibodies Bs71D8, Bs80A8, Bs155C2 and the positive control BM03 in the presence of MM.1R cells.

[0287] FIG8 shows the results of T cell cytotoxicity assays induced by the anti-GPRC5D×CD3 bispecific antibody Bs80A8 and the positive control DuobodyBM in the presence of MM.1R cells.

[0288] FIG9 shows the results of the T cell cytotoxicity assay induced by the anti-GPRC5D×CD3 bispecific antibodies Bs71D8, Bs80A8, Bs155C2 and the positive control BM03 in the presence of MM.1S cells.

[0289] FIG10 shows the results of the T cell cytotoxicity assay induced by the anti-GPRC5D×CD3 bispecific antibody Bs80A8 and the positive control DuobodyBM in the presence of MM.1S cells.

[0290] FIG11 shows the results of the T cell cytotoxicity assay induced by the anti-GPRC5D×CD3 bispecific antibodies Bs71D8, Bs80A8, Bs155C2 and the positive control BM03 in the presence of RPMI 8226 cells.

[0291] FIG12 shows the results of T cell cytotoxicity assays induced by the anti-GPRC5D×CD3 bispecific antibody Bs80A8 and the positive control DuobodyBM in the presence of RPMI 8226 cells.

[0292] FIG13 shows the in vivo inhibitory effect of the anti-GPRC5D×CD3 bispecific antibody on multiple myeloma. DETAILED DESCRIPTION

[0293] the term

[0294] The terms used herein are for the purpose of describing the embodiments only and are not intended to be limiting. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs.

[0295] Unless the context clearly requires otherwise, throughout the specification and claims, the words "comprising," "having," "including," and the like should be understood to mean "including but not limited to." Unless otherwise specified, "comprising" includes "consisting of." For example, for GPRC5D-VH comprising the HCDR1 set forth in SEQ ID NO: 43, it explicitly encompasses the HCDR1 with the amino acid sequence set forth in SEQ ID NO: 43.

[0296] A target refers to the object to which the therapeutically active ingredients of the present disclosure (bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof) are directed. A target can be a nucleic acid (gene, mRNA, etc.) or a protein (precursor, mature protein, isoform, modified form, free, surface-expressed). In the present disclosure, a target particularly refers to a protein. As an example, the bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof of the present disclosure target GPRC5D. As another example, the bispecific antibodies of the present disclosure target GPRC5D and CD3.

[0297] The nucleotide or amino acid information of GPRC5D and CD3 as targets is well known in the art and can be obtained, for example but not limited to, from literature or databases.

[0298] In the context of this disclosure, GPRC5D should be understood broadly to include various forms of GPRC5D molecules at various stages, such as, but not limited to, molecules produced during amplification, replication, transcription, splicing, processing, translation, and modification of the GPRC5D gene, such as cDNA, mRNA, precursor protein, mature protein, and fragments thereof. In specific embodiments, GPRC5D refers to human GPRC5D. In some specific embodiments, human GPRC5D refers to mature GPRC5D protein, particularly GPRC5D expressed on the cell surface.

[0299] In the context of this disclosure, CD3 should be broadly understood to include various forms of CD3 molecules at various stages, such as, but not limited to, molecules produced during CD3 gene amplification, replication, transcription, splicing, processing, translation, and modification, such as cDNA, mRNA, precursor protein, mature protein, and fragments thereof. In specific embodiments, CD3 refers to human CD3. In some specific embodiments, human CD3 refers to mature CD3 protein, particularly CD3 expressed on the cell surface.

[0300] In the field of antibodies, targets typically exist in the form of antigens. "Antigen" refers to a molecule or portion thereof that can be selectively recognized or bound by an antigen-binding molecule (e.g., a bispecific antibody, anti-GPRC5D antibody, or antigen-binding fragment thereof of the present disclosure). An antigen may have one or more epitopes.

[0301] "Epitope" refers to a region on an antigen that is capable of specific binding to an antibody or its antigen-binding fragment. An epitope can be formed by contiguous amino acids (linear epitope); or comprise non-contiguous amino acids (conformational epitope). An epitope comprises at least 3, at least 4, at least 5, at least 6, at least 7, or 8-10 amino acids. Routine methods in the art can be used to screen for antibodies or their antigen-binding fragments that bind to a specific epitope, such as, but not limited to, alanine scanning, peptide cleavage analysis, epitope extraction, and chemical modification of the antigen.

[0302] "Antibody" is used in the broadest sense and covers various antibody structures, including but not limited to monoclonal antibodies, polyclonal antibodies, and full-length antibodies, as long as they exhibit the desired antigen-binding activity. Typically, natural IgG antibodies are heterotetrameric proteins composed of two light chains and two heavy chains bound by disulfide bonds. From N to C-terminus, each heavy chain has a variable region (VH) and three constant domains (CH1, CH2, and CH3). From N to C-terminus, each light chain has a variable region (VL) and a constant light domain (CL). Depending on the context, a technician can determine the specific meaning of "antibody".

[0303] The "class" of an antibody refers to the type of constant domain or constant region possessed by its heavy chain. Antibodies are mainly divided into five classes: IgA, IgD, IgE, IgG, and IgM, some of which can be further divided into subclasses (isotypes), such as IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2. The heavy chain constant domains corresponding to different classes of immunoglobulins are called α, δ, ε, γ, and μ, respectively. "Specific binding" means that the bispecific antibody, anti-GPRC5D antibody, or antigen-binding fragment thereof of the present disclosure binds to the targeted antigen or epitope with higher affinity than other antigens or epitopes thereof. Typically, about 1×10 -7 An equilibrium dissociation constant (KD) of M or less is considered to be "specific" binding. KD can be measured using known methods, such as FACS or surface plasmon resonance. "Affinity" is used to describe the intensity of non-covalent interactions between bispecific antibodies, anti-GPRC5D antibodies or their antigen-binding fragments and their antigens or their epitopes. Affinity is typically represented by the equilibrium dissociation constant (KD). "kassoc" or "ka" refers to the on-rate of a specific antibody-antigen interaction, and "kdis" or "kd" is intended to refer to the off-rate of a specific antibody-antigen interaction. "KD" is derived from the ratio of kd to ka (i.e., kd / ka), expressed as molar concentration.

[0304] "Specific binding" does not exclude cross-reactivity to homologous antigens from other species (eg, cynomolgus monkey (Macaca fascicularis), chimpanzee (Pan troglodytes), or marmoset (Callithrix jacchus).

[0305] In this regard, the terms "anti-GPRC5D..." and "specifically binds to GPRC5D..." refer to bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof that are capable of specifically recognizing or binding to GPRC5D (or an epitope thereof). The terms "specifically binds to CD3..." refer to bispecific antibodies that are capable of specifically recognizing or binding to CD3 (or an epitope thereof).

[0306] "Binding moiety" refers to a module that specifically binds to an antigen or an epitope thereof. Exemplary binding moieties include antigen-binding domains of antibodies, such as, but not limited to, heavy chain variable regions and light chain variable regions.

[0307] "A binding moiety that specifically binds to GPRC5D" refers to a moiety that is capable of binding to GPRC5D or an epitope thereof with sufficient affinity. For example, the binding moiety comprises an antigen binding fragment as defined herein. In specific embodiments, the binding moiety that specifically binds to GPRC5D is a Fab or scFv.

[0308] A "binding moiety that specifically binds to CD3" refers to a moiety that is capable of binding to CD3 or an epitope thereof with sufficient affinity. For example, the binding moiety comprises an antigen binding fragment as defined herein. In specific embodiments, the binding moiety that specifically binds to CD3 is a Fab or scFv.

[0309] "Fully human antibodies" include antibodies having variable and constant regions of human germline immunoglobulin sequences.

[0310] A "humanized antibody" is an antibody produced by grafting non-human CDR sequences into the framework of a human antibody variable region.

[0311] A "chimeric antibody" is an antibody formed by fusing the variable region of an antibody from one species (eg, mouse) with the constant region of an antibody from another species (eg, human).

[0312] "Antibody fragments" or "antigen-binding fragments" are molecules other than intact antibodies that contain a portion of an intact antibody that retains the antigen-binding ability of the intact antibody. Examples of antibody fragments include, but are not limited to, Fv, Fab, Fab', Fab'-SH, F(ab')2, single-domain antibodies, single-chain Fab (scFab), diabodies, linear antibodies, single-chain antibodies (e.g., scFv); and multispecific antibodies formed from antibody fragments.

[0313] "Fab" consists of a light chain and the CH1 and variable region of a heavy chain.

[0314] "Fab' fragment", which is a Fab fragment having one or more cysteine ​​residues at the C-terminus of the CH1 domain.

[0315] "F(ab')2 fragment" is a bivalent fragment formed by two Fab' fragments linked by a disulfide bridge at the hinge region.

[0316] "Fab'-SH" refers to Fab' in which the cysteine ​​residue(s) of the constant domains bear a free thiol group.

[0317] A "single-chain Fab fragment" is a polypeptide consisting of an antibody heavy chain variable domain (VH), an antibody constant domain 1 (CH1), an antibody light chain variable domain (VL), an antibody light chain constant domain (CL), and a linker, wherein the antibody domain and the linker have one of the following orders from N-terminus to C-terminus: a) VH-CH1-linker-VL-CL, b) VL-CL-linker-VH-CH1, c) VH-CL-linker-VL-CH1 or d) VL-CH1-linker-VH-CL; and wherein the linker is a peptide linker. In some embodiments, the peptide linker is a polypeptide of at least 30 amino acids, preferably a polypeptide of 32-50 amino acids.

[0318] "Diabodies" have two antigen-binding sites and are composed of a heavy-chain variable domain (VH) and a light-chain variable domain (VL) connected to each other in the same polypeptide chain.

[0319] "Linear antibodies" comprise a pair of tandem Fd segments (VH-CH1-VH-CH1), which together with complementary light chain polypeptides form a pair of antigen binding regions.

[0320] An "Fv fragment" has the VL and VH domains of one arm of an antibody.

[0321] "Single-domain antibodies" are antibody fragments that contain all or a portion of the heavy chain variable domain or all or a portion of the light chain variable domain of an antibody.

[0322] A single-chain antibody fragment (scFv) is an antibody composed of a heavy chain variable region and a light chain variable region connected by a linker.

[0323] "Fc" contains two heavy chain fragments, including the CH2 and CH3 domains. The two heavy chain fragments are held together by disulfide bonds and hydrophobic interactions within the CH3 domains. "Variable region" refers to the domain of an antibody or antigen-binding fragment that binds to the antigen. "Complementarity determining region" or "CDR" refers to the region within the variable region that primarily contributes to antigen binding. VH and VL each contain four framework regions (FRs) and three complementarity determining regions (CDRs). VH contains three CDR regions: HCDR1, HCDR2, and HCDR3; VL contains three CDR regions: LCDR1, LCDR2, and LCDR3. From N-terminus to C-terminus, each VH and VL has the following sequence: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4.

[0324] "Framework" or "FR" refers to the variable domain residues outside the hypervariable region (CDR) residues. The FR of a variable domain is generally composed of four FR domains: FR1, FR2, FR3, and FR4. Thus, the HVR and FR sequences generally appear in the following order in VH (or VL): FR1-H1(L1)-FR2-H2(L2)-FR3-H3(L3)-FR4.

[0325] The heavy chain variable region in the binding portion that specifically binds to GPRC5D is denoted as GPRC5D-VH, and the light chain variable region is denoted as GPRC5D-VL.

[0326] The heavy chain variable region in the binding portion that specifically binds to CD3 is denoted as CD3-VH, and the light chain variable region is denoted as CD3-VL.

[0327] The three CDR regions in GPRC5D-VH are represented as GPRC5D-HCDR1, GPRC5D-HCDR2 and GPRC5D-HCDR3; the three CDR regions in GPRC5D-VL are represented as GPRC5D-LCDR1, GPRC5D-LCDR2 and GPRC5D-LCDR3.

[0328] The three CDR regions in CD3-VH are represented as CD3-HCDR1, CD3-HCDR2 and CD3-HCDR3; the three CDR regions in CD3-VL are represented as CD3-LCDR1, CD3-LCDR2 and CD3-LCDR3.

[0329] The amino acid sequence boundaries of CDRs can be determined by various well-known schemes, such as: the Kabat numbering system (see Kabat et al. (1991), "Sequences of Proteins of Immunological Interest", 5th ed., Public Health Service, National Institutes of Health, Bethesda, MD), the Chothia numbering system, and the ImMunoGenTics (IMGT) numbering system (Lefranc, MP et al., Dev. Comp. Immunol., 27, 55-77 (2003); Front Immunol. 2018 Oct 16; 9:2278).

[0330] The correspondence between various numbering systems is well known to those skilled in the art. In other words, when a CDR sequence and its position in an antibody are provided under one numbering system, a skilled person is capable of determining the corresponding CDR sequence and its position in an antibody under another numbering system. Technical solutions corresponding to different numbering systems will be considered equivalent technical solutions.

[0331] "Linker" refers to a connecting unit that connects two polypeptide fragments. In the present disclosure, the linkers appearing in the same structural formula may be the same or different. The linker may be a peptide linker, which comprises one or more amino acids, a typical example being about 1-40 amino acids. The linker disclosed herein may be any suitable peptide chain, as long as the antibody or antigen-binding fragment can exhibit the desired antigen-binding activity. For example, the peptide linker may be a flexible peptide of 1-40 amino acid residues. In some embodiments, the peptide linkers each independently have a structure of (GGGGS)n, wherein n is 1, 2, 3, 4, 5, 6, 7, or 8. In some embodiments, the peptide linker is shown in SEQ ID NO: 200.

[0332] In the expression "...having at least 85% sequence identity...", identity refers to the degree (percentage) to which the amino acids / nucleic acids of the two sequences are identical at equivalent positions when the two sequences are optimally aligned. During the alignment, gaps are introduced, if necessary, to maximize sequence identity. Sequence identity is determined by techniques known in the art, such as computer software (BLAST, BLAST-2, ALIGN, ALIGN-2, or Megalign).

[0333] As an example, "the heavy chain variable region comprises an amino acid sequence that has at least 85% sequence identity with SEQ ID NO: 41" means that the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 43, HCDR2 shown in SEQ ID NO: 44, and HCDR3 shown in SEQ ID NO: 45, and amino acid mutations are allowed to be introduced into regions outside the CDRs so as to have at least 85% sequence identity with SEQ ID NO: 41.

[0334] "Amino acid mutation" includes amino acid substitution, deletion, insertion, modification or any combination thereof. Any combination of substitution, deletion, insertion and modification can be performed to achieve the final construct, as long as the final construct has the desired properties, such as amino acid substitutions that reduce Fc region homodimerization. Amino acid substitutions can be introduced into the antibody of interest, and the product can be screened for the desired activity, such as retained / improved antigen binding, reduced immunogenicity. Amino acid sequence deletions and insertions include deletions and insertions at the amino terminus and / or carboxyl terminus of the polypeptide chain. In one embodiment, the amino acid mutation is a non-conservative amino acid substitution, that is, an amino acid is replaced with another amino acid having different structural and / or chemical properties. Amino acid mutations can be generated using genetic or chemical methods well known in the art. Genetic methods can include site-directed mutagenesis, PCR, gene synthesis, etc.

[0335] The two subunits in the Fc region may cause undesirable homodimerization. In order to improve yield and purity, it would be advantageous to introduce modifications that promote heterodimerization in the Fc region. In some specific embodiments, the Fc region is substituted so that it has a hole structure or a protrusion structure according to the knob-into-hole technique (KIH). The hole structure (hole) is introduced in the first subunit and the protrusion structure (knob) is introduced in the second subunit. The protrusion structure is positioned in the hole structure, promoting the formation of heterodimers and inhibiting the generation of homodimers. The protrusion structure is constructed by replacing smaller amino acid side chains with larger amino acid side chains (such as tyrosine or tryptophan). The hole structure is constructed by replacing larger amino acid side chains with smaller amino acid side chains (such as alanine or threonine). Optional amino acid substitutions are shown in the following table:

[0336] Table 1. KIH mutation combinations

[0337] For example, in the first subunit, the amino acid at position 366 is substituted with S, the amino acid at position 368 is substituted with A, the amino acid at position 407 is substituted with V, and the amino acid at position 366 in the second subunit is substituted with W (numbering is according to the EU index). In addition to the knob-in-hole technique, other techniques for modifying the CH3 domain of the heavy chain to achieve heterodimerization are also known in the art, such as WO1996027011A1, WO1998050431, EP1870459, WO2007110205, WO2009089004, WO2010129304, WO201190754, WO2011143545, WO2012058768, WO2013157954 and WO2013096291.

[0338] In the present disclosure, various methods can be used to indicate the same amino acid mutation. For example, the amino acid residue at a specific site can be indicated by position + amino acid residue. For example, 366S, 368A indicates that the amino acid residue at site 366 is S and the amino acid residue at site 368 is A.

[0339] As a supplement, in the bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof of the present application, although the C-terminus of the Fc region is a complete C-terminus ending in PGK, it can also be a truncated C-terminus. Exemplarily, one or two C-terminal residues are removed in the truncated C-terminus (e.g., a truncated C-terminus ending in PG). Compositions comprising antibodies may include: antibodies with complete C-termini and antibodies with truncated C-termini.

[0340] "Bispecific antibody" refers to an antibody that can specifically bind to two different antigens (or two different epitopes of the same antigen). The prior art has disclosed bispecific antibodies of various structures. Exemplary bispecific antibody structural models include KIH, CrossMAb, Triomab quadroma, FcΔAdp, ART-Ig, BiMAb, Biclonics, BEAT, DuoBody, Azymetric, XmAb, 2:1TCBs, 1Fab-IgG TDB, FynomAb, two-in-one / DAF, scFv-Fab-IgG, DART-Fc, LP-DART, CODV-Fab-TL, HLE-BiTE, F(ab)2-CrossMAb, IgG-(scFv)2, Bs4Ab, DVD-Ig, Tetravalent-DART-Fc, (scFv)4-Fc, CODV-Ig, mAb2, F(ab)4-CrossMAb, etc.

[0341] The bispecific antibodies disclosed herein are not limited to a specific molecular structure, as long as they have the desired antigen-binding function. The antigen-binding portion can be any antibody fragment with antigen-binding activity, which is fused via a peptide linker.

[0342] Exemplarily, the bispecific antibody of the present disclosure comprises a first chain having a structure shown in Formula a, a second chain having a structure shown in Formula b, and a third chain having a structure shown in Formula c:

[0343] Formula a: [GPRC5D-VH]-[CH1]-[Fc1];

[0344] Formula b: [GPRC5D-VL]-[CL]; and

[0345] Formula c: [CD3-VL]-[GGGGSGGGGSGGGGSGGGGS]-[CD3-VH]-[Fc2];

[0346] The positions of Fc1 and Fc2 are interchangeable.

[0347] Exemplarily, the bispecific antibody of the present disclosure comprises a first chain having a structure shown in Formula a, a second chain having a structure shown in Formula b, a third chain having a structure shown in Formula d, and a fourth chain having a structure shown in Formula e:

[0348] Formula a: [GPRC5D-VH]-[CH1]-[Fc1];

[0349] Formula b: [GPRC5D-VL]-[CL];

[0350] Formula d: [CD3-VH]-[CH1]-[Fc2]; and

[0351] Formula e: [CD3-VL]-[CL];

[0352] The positions of Fc1 and Fc2 are interchangeable.

[0353] Exemplary anti-GPRC5D antibodies or antigen-binding fragments thereof

[0354] In specific embodiments, the anti-GPRC5D antibodies or antigen-binding fragments thereof of the present disclosure comprise a GPRC5D-VH and a GPRC5D-VL selected from any one of the following groups:

[0355] 1) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 43, HCDR2 of SEQ ID NO: 44, and HCDR3 of SEQ ID NO: 45; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 48, LCDR2 of SEQ ID NO: 49, and LCDR3 of SEQ ID NO: 50;

[0356] 2) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 33, HCDR2 of SEQ ID NO: 34, and HCDR3 of SEQ ID NO: 35; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 38, LCDR2 of SEQ ID NO: 39, and LCDR3 of SEQ ID NO: 40;

[0357] 3) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 93, HCDR2 of SEQ ID NO: 94, and HCDR3 of SEQ ID NO: 95; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 98, LCDR2 of SEQ ID NO: 99, and LCDR3 of SEQ ID NO: 100;

[0358] 4) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 23, HCDR2 of SEQ ID NO: 24, and HCDR3 of SEQ ID NO: 25; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 28, LCDR2 of SEQ ID NO: 29, and LCDR3 of SEQ ID NO: 30;

[0359] 5) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 63, HCDR2 of SEQ ID NO: 64, and HCDR3 of SEQ ID NO: 65; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 68, LCDR2 of SEQ ID NO: 69, and LCDR3 of SEQ ID NO: 70;

[0360] 6) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 83, HCDR2 of SEQ ID NO: 84, and HCDR3 of SEQ ID NO: 85; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 88, LCDR2 of SEQ ID NO: 89, and LCDR3 of SEQ ID NO: 90;

[0361] 7) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 3, HCDR2 shown in SEQ ID NO: 4, and HCDR3 shown in SEQ ID NO: 5; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 8, LCDR2 shown in SEQ ID NO: 9, and LCDR3 shown in SEQ ID NO: 10;

[0362] 8) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 13, HCDR2 of SEQ ID NO: 14, and HCDR3 of SEQ ID NO: 15; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 18, LCDR2 of SEQ ID NO: 19, and LCDR3 of SEQ ID NO: 20;

[0363] 9) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 53, HCDR2 of SEQ ID NO: 54, and HCDR3 of SEQ ID NO: 55; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 58, LCDR2 of SEQ ID NO: 59, and LCDR3 of SEQ ID NO: 60;

[0364] 10) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 73, HCDR2 of SEQ ID NO: 74, and HCDR3 of SEQ ID NO: 75; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 78, LCDR2 of SEQ ID NO: 79, and LCDR3 of SEQ ID NO: 80;

[0365] 11) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 103, HCDR2 of SEQ ID NO: 104, and HCDR3 of SEQ ID NO: 105; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 108, LCDR2 of SEQ ID NO: 109, and LCDR3 of SEQ ID NO: 110;

[0366] 12) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 113, HCDR2 of SEQ ID NO: 114, and HCDR3 of SEQ ID NO: 115; and the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 118, LCDR2 of SEQ ID NO: 119, and LCDR3 of SEQ ID NO: 120;

[0367] 13) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 123, HCDR2 shown in SEQ ID NO: 124, and HCDR3 shown in SEQ ID NO: 125; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 128, LCDR2 shown in SEQ ID NO: 129, and LCDR3 shown in SEQ ID NO: 130; and

[0368] 14) the GPRC5D-VH comprises HCDR1 of SEQ ID NO: 133, HCDR2 of SEQ ID NO: 134, and HCDR3 of SEQ ID NO: 135; the GPRC5D-VL comprises LCDR1 of SEQ ID NO: 138, LCDR2 of SEQ ID NO: 139, and LCDR3 of SEQ ID NO: 140;

[0369] Among them, CDRs are determined according to the Kabat, Chothia or IMTG numbering systems.

[0370] In specific embodiments, the anti-GPRC5D antibodies or antigen-binding fragments thereof of the present disclosure comprise a GPRC5D-VH and a GPRC5D-VL selected from any one of the following groups:

[0371] 1) GPRC5D-VH shown in SEQ ID NO: 41, and GPRC5D-VL shown in SEQ ID NO: 46;

[0372] 2) GPRC5D-VH shown in SEQ ID NO: 31, and GPRC5D-VL shown in SEQ ID NO: 36;

[0373] 3) GPRC5D-VH shown in SEQ ID NO: 91, and GPRC5D-VL shown in SEQ ID NO: 96;

[0374] 4) GPRC5D-VH shown in SEQ ID NO: 21, and GPRC5D-VL shown in SEQ ID NO: 26;

[0375] 5) GPRC5D-VH shown in SEQ ID NO: 61, and GPRC5D-VL shown in SEQ ID NO: 66;

[0376] 6) GPRC5D-VH shown in SEQ ID NO: 81, and GPRC5D-VL shown in SEQ ID NO: 86;

[0377] 7) GPRC5D-VH shown in SEQ ID NO: 1, and GPRC5D-VL shown in SEQ ID NO: 6;

[0378] 8) GPRC5D-VH shown in SEQ ID NO: 11, and GPRC5D-VL shown in SEQ ID NO: 16;

[0379] 9) GPRC5D-VH shown in SEQ ID NO: 51, and GPRC5D-VL shown in SEQ ID NO: 56;

[0380] 10) GPRC5D-VH shown in SEQ ID NO: 71, and GPRC5D-VL shown in SEQ ID NO: 76;

[0381] 11) GPRC5D-VH shown in SEQ ID NO: 101, and GPRC5D-VL shown in SEQ ID NO: 106;

[0382] 12) GPRC5D-VH shown in SEQ ID NO: 111, and GPRC5D-VL shown in SEQ ID NO: 116;

[0383] 13) GPRC5D-VH shown in SEQ ID NO: 121, and GPRC5D-VL shown in SEQ ID NO: 126; and

[0384] 14) GPRC5D-VH represented by SEQ ID NO: 131, and GPRC5D-VL represented by SEQ ID NO: 136.

[0385] Exemplary bispecific antibodies

[0386] In a specific embodiment, the bispecific antibody of the present disclosure comprises a group selected from:

[0387] 1) comprising a first chain represented by SEQ ID NO: 161, a second chain represented by SEQ ID NO: 163, and a third chain represented by SEQ ID NO: 159;

[0388] 2) comprising a first strand set forth in SEQ ID NO: 165, a second strand set forth in SEQ ID NO: 167, and a third strand set forth in SEQ ID NO: 159;

[0389] 3) comprising the first chain shown in SEQ ID NO: 169, the second chain shown in SEQ ID NO: 171, and the third chain shown in SEQ ID NO: 159; and

[0390] 4) comprising the first chain represented by SEQ ID NO: 173, the second chain represented by SEQ ID NO: 175, the third chain represented by SEQ ID NO: 177, and the fourth chain represented by SEQ ID NO: 179.

[0391] "Nucleic acid" is used interchangeably with "polynucleotide" and refers to deoxyribonucleotides or ribonucleotides and polymers thereof in single-stranded or double-stranded form. The nucleic acids are synthetic, naturally occurring, and non-naturally occurring. Unless otherwise indicated, a nucleic acid sequence also encompasses conservative variants (e.g., degenerate substitutions) and complementary sequences thereof, as well as explicitly designated sequences. The term "nucleic acid molecule" includes a plurality of nucleic acid molecules.

[0392] "Vector" means a polynucleotide molecule capable of transporting another polynucleotide to which it is attached. One type of vector is a "plasmid," which refers to a circular double-stranded DNA loop into which an exogenous DNA segment is attached. Another type of vector is a viral vector, such as an adeno-associated viral vector (AAV), in which an exogenous DNA segment is attached to the viral genome. Some vectors are capable of autonomous replication in host cells, while others can integrate into the host's genome, thereby replicating along with the host genome.

[0393] "Host cell" and "cell line" are used interchangeably and refer to cells into which exogenous nucleic acid has been introduced and their progeny, regardless of the number of passages through the progeny. Progeny are not required to be completely identical to the parent cell in terms of nucleic acid and may contain mutations, as long as the progeny with the mutation have the same desired function or activity as the original cell.

[0394] The host cell cannot develop into a complete animal or plant individual.

[0395] Host cells include prokaryotic and eukaryotic host cells. Eukaryotic host cells include, but are not limited to, mammalian cells, insect cells, plant cells, and fungal cells. Mammalian cells include human, mouse, rat, dog, monkey, pig, goat, cow, horse, and hamster cells. Exemplary host cells include, but are not limited to, CHO, NSO, COS, SP2 cells, HeLa cells, BHK cells, human hepatocellular carcinoma cells, A549 cells, 3T3 cells, and HEK-293 cells. Fungal cells include yeast, such as, but not limited to, Pichia pastoris, Saccharomyces cerevisiae, Hansenula polymorpha, and Kluyveromyces.

[0396] The bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof of the present disclosure can be produced using recombinant methods.

[0397] For example, when the bispecific antibody is a heterodimer, three encoding nucleic acids are required: one encoding the first heavy chain comprising the first subunit of the Fc region, one encoding the first light chain, and one encoding the scFv comprising the second subunit of the Fc region. Alternatively, four encoding nucleic acids may be used: one encoding the first light chain, one encoding the first heavy chain comprising the first subunit of the Fc region, one encoding the second light chain, and one encoding the second heavy chain comprising the second subunit of the Fc region. These three or four nucleic acids are expressed in one or more expression vectors. Also provided are host cells containing these expression vectors.

[0398] In a specific embodiment, a host cell containing the expression vector is cultured under conditions suitable for expression of the antibody, and the antibody is recovered (optionally purified) from the host cell (or its culture).

[0399] A "pharmaceutical composition" refers to a mixture containing one or more bispecific antibodies, anti-GPRC5D antibodies, or antigen-binding fragments thereof of the present disclosure and other chemical components, such as pharmaceutically acceptable carriers, diluents, buffers, or excipients.

[0400] A "pharmaceutically acceptable carrier, diluent, buffer, or excipient" refers to an ingredient in a pharmaceutical formulation that is different from the active ingredient and is non-toxic to the subject. Pharmaceutically acceptable carriers, diluents, buffers, or excipients include, but are not limited to, buffers, excipients, stabilizers, and preservatives.

[0401] "Subject" or "individual" refers to an animal, preferably a mammal. According to specific embodiments, the subject is a mammal, including, for example, camels, horses, cows, pigs, sheep, cats, dogs, rabbits, rats, guinea pigs, mice, primates (e.g., humans). In specific embodiments, the subject is a human.

[0402] In specific embodiments, the subject is an individual susceptible to, suspected of having, or already having a disease.

[0403] "Treatment" means providing a bispecific antibody, anti-GPRC5D antibody, or antigen-binding fragment thereof, or a pharmaceutical composition thereof, to a subject having one or more symptoms of a disease. Typically, the bispecific antibody, anti-GPRC5D antibody, or antigen-binding fragment thereof, is administered to the subject or subject population being treated in an amount effective to alleviate the symptoms of the disease.

[0404] In specific embodiments, the selection of an effective amount can be determined by one skilled in the art based on consideration of a variety of factors (e.g., through clinical trials), including the disease to be treated, the symptoms involved, the route of administration, the severity of the disease, the subject's weight, the subject's immune status, and other factors known to one skilled in the art.

[0405] The effective amount in the specific embodiment can be obtained from the dose-response curve derived from the animal model test system, and is allowed to be determined according to the doctor's judgment and the situation of each subject. As an example, the amount of the drug required for a single administration to a subject can be conveniently obtained by calculating the product of the subject's body weight and the unit weight dose required for the subject's single administration. For example, in the process of preparing a drug, it is generally believed that the adult body weight is 50-70 kg, and the dosage can be initially determined by the equivalent dose conversion relationship between the unit weight dose of the experimental animal and that of a human. For example, it can be determined based on the guidance opinions proposed by drug administration agencies such as the SFDA and the FDA. In some embodiments, the dosage of humans and mice can be converted using a body surface area conversion coefficient of 0.0026 based on humans and mice.

[0406] The active ingredient herein (e.g., a bispecific antibody, an anti-GPRC5D antibody, or an antigen-binding fragment thereof) can be administered all at once, or can be divided into a number of smaller unit doses, administered at intervals. It should be understood that the dosage, duration, and interval of treatment are a function of the disease being treated and can be determined by inference using animal or clinical trial data. The administration can include a single administration, or two or more administrations spaced at appropriate intervals. The interval between two adjacent administrations can be 30 minutes, 40 minutes, 50 minutes, 60 minutes, 2 hours, 3 hours, 4 hours, 5 hours, 6 hours, 7 hours, 8 hours, 9 hours, 10 hours, 12 hours, 14 hours, 16 hours, 18 hours, 20 hours, 22 hours, 24 hours, one and a half days, 2 days, 3 days, 4 days, 5 days, 6 days, 7 days, 8 days, 9 days, 10 days, 1 week, 2 weeks, 3 weeks, 4 weeks, 5 weeks, 6 weeks, 1 month, 2 months, 3 months, 4 months, 5 months, 6 months, 7 months, 8 months, 9 months, 10 months, 11 months or 12 months.

[0407] It should be understood that when a numerical range is disclosed, for example, "A to B" is a shorthand way of writing that, although not every point value in the range is given, it is considered that the integers and decimals within the range have been specifically disclosed.

[0408] “And / or”, for example, “A and / or B” should be understood to mean “A and B” or “A or B”.

[0409] "Optional" or "optionally" means that the subsequently described event or circumstance may but need not occur. As used in the specification and claims, the singular forms "a", "an" include the corresponding plural referents unless the content clearly dictates otherwise.

[0410] Example

[0411] The following examples are provided to provide a better understanding of the subject matter of the present invention. These examples should not be construed as limiting the subject matter described. Rather, it should be understood that the examples and embodiments described herein are for illustrative purposes only, and various modifications or variations thereof will be apparent to those skilled in the art and are within the scope of the present invention.

[0412] Example 1: Obtaining human monoclonal antibodies against human GPRC5D based on a humanized mouse platform and hybridoma technology

[0413] Using the fully humanized antibody mouse platform (AceMouse) of Shanghai Taijin Biotechnology Co., Ltd. (referred to as "Taijin Bio", English name AceMab) TM ), and prepared humanized anti-human GPRC5D monoclonal antibodies using hybridoma technology.

[0414] Two groups of mice were immunized using DNA and cell-based multiple rounds of immunization, respectively.

[0415] DNA immunogen: The complete DNA coding sequence of human GPRC5D (hGPRC5D) (CDS, SEQ ID NO: 200) was inserted into the expression vector of Taijin Biotechnology to construct the GPRC5D expression vector for immunization.

[0416] Cell immunization: CHO-K1 cells expressing hGPRC5D (CHO-K1_hGPRC5D, Kangyuan Bochuang Biotechnology Co., Ltd.) were used for immunization.

[0417] Immunization protocol: Group A used DNA immunization (8 mice), and Group B used cell immunization (8 mice). A total of six immunizations were performed, including the initial immunization, four booster immunizations, and the final booster immunization. The titer of anti-hGPRC5D antibodies in mouse serum was assessed 4 days after each immunization. Based on the antibody titer in the serum after three booster immunizations, 10 mice with high antibody titers were selected and hybridoma fusion was performed 3 days after the final booster immunization to obtain hybridoma cells. A positive control monoclonal antibody BM01 was set up in the experiment. The variable region was derived from the GCDB72 antibody disclosed in Table 23 of WO 2018017786 A2, comprising the GPRC5D binding portion of GCDB72, and the constant region was mouse IgG1 (antibody sequence see SEQ ID NO: 141, SEQ ID NO: 142).

[0418] The antibodies produced by the hybridomas were tested by binding to HEK293T cells stably expressing hGPRC5D (HEK293T_hGPRC5D), HEK293T cells stably expressing cynomolgus macaque GPRC5D (CDS, SEQ ID NO: 212) (HEK293T_cynoGPRC5D), HEK293T cells stably expressing mouse GPRC5D (CDS, SEQ ID NO: 213) (HEK293T_mGPRC5D), HEK293T cells stably expressing human GPRC5A (CDS, SEQ ID NO: 214) (HEK293T_GPRC5A), HEK293T cells stably expressing human GPRC5B (CDS, SEQ ID NO: 215) (HEK293T_GPRC5B), and HEK293T cells stably expressing human GPRC5C (CDS, SEQ ID NO: 216). NO: 216) HEK293T cells (HEK293T_GPRC5C) were used to screen for antibodies that specifically recognize GPRC5D. The specific method is as follows:

[0419] The antibody was diluted into eight dilutions starting at 60 μg / mL and incubated with the above HEK293T cells for 30 minutes at 4°C. The cells were washed twice by centrifugation at 1200 rpm for 5 minutes. The cells were then incubated with a secondary antibody, PE goat anti-mouse IgG (Invitrogen, #12-4010-87), and PE signal was measured by flow cytometry. BM01 antibody at 5 μg / mL was used as a positive control. The screening results are shown in Figures 1 and 2. Finally, 14 clones were selected, including monoclonal clones 53C10, 47G4, 71D8, 78G1, 80A8, 91A1, 56A7, 53E2, 92C5, 155C2, 165B7, 199B11, 154D12 and 192E2, which were of IgG subtype and bound to human, monkey, or human, mouse and monkey GPRC5D, but not to human GPRC5A, GPRC5B and GPRC5C (see Tables 2-3 for sequence numbers).

[0420] BM01 heavy chain (SEQ ID NO: 141)

[0421] BM01 light chain (SEQ ID NO: 142)

[0422] Table 2. Amino acid sequence numbering of anti-GPRC5D antibodies

[0423] Table 3. VH and VL coding DNA numbers of anti-GPRC5D antibodies

[0424] Example 2: Construction and evaluation of anti-GPRC5D antibodies

[0425] Monoclonal hybridoma cells were collected, RNA was extracted, and reverse transcribed to obtain cDNA, which was amplified and sequenced to obtain the amino acid sequence of the variable region of the antibody in the hybridoma cell line. The variable region of the antibody was fused with a human constant region (such as the constant region set forth in SEQ ID NOs: 143 and 144) to obtain the final fully human anti-GPRC5D antibody. The variable region and CDR sequences of the 14 anti-GPRC5D antibodies obtained in this disclosure are shown in Tables 5 and 6, with the heavy and light chain sequences of 47G4, 71D8, 80A8, 78G1, 53E2, and 155C2 shown in Table 7.

[0426] Flow cytometry was used to analyze the binding of fully human anti-GPRC5D antibodies to HEK293T_hGPRC5D cells. A positive control monoclonal antibody, BM02, whose variable regions are derived from the GCDB72 antibody disclosed in Table 23 of WO2018017786A2, with the heavy chain sequence shown in SEQ ID NO: 157 and the light chain sequence shown in SEQ ID NO: 158, was used. HEK293T_hGPRC5D cells were incubated with various concentrations of anti-GPRC5D antibody (maximum concentration: 10 μg / ml, 3-fold dilution, for a total of 7 concentration points) at 4°C for 30 min. After washing the cells twice by centrifugation at 1200 rpm for 5 min, Goat anti-Human IgG (H+L) Cross-Adsorbed Secondary Antibody, AF488 (Invitrogen, Catalog No. A-11013, 1:1000 dilution) was added and incubated at 4°C in the dark for 30 min. After washing the cells twice, flow cytometry was used to detect the cells. The results are shown in Table 4.

[0427] The results showed that the hGPRC5D binding activities of 47G4, 71D8, 80A8, 78G1, 53E2 and 155C2 were better than that of the positive reference BM02.

[0428] BM02 heavy chain (SEQ ID NO: 157)

[0429] BM02 light chain (SEQ ID NO: 158)

[0430] Heavy chain constant region (SEQ ID NO: 143)

[0431] Light chain constant region (SEQ ID NO: 144)

[0432] Table 4. Binding activity of anti-GPRC5D antibodies to HEK293T_hGPRC5D cells

[0433] Table 5. Variable region sequences of anti-GPRC5D antibodies disclosed herein

[0434] Table 6. CDR sequences of anti-GPRC5D antibodies of the present disclosure

[0435] Table 7. Heavy and light chain sequences of anti-GPRC5D antibodies of the present disclosure

[0436] Example 3: Preparation of GPRC5D×CD3 bispecific antibody

[0437] The CD3 arm of the GPRC5D×CD3 bispecific antibody disclosed herein can be derived from any suitable anti-CD3 antibody, and the structure of the bispecific antibody can be any structure known in the art. Exemplarily, the bispecific antibody disclosed herein has the following structure:

[0438] Structure 1: scFv-Fab-Fc, which contains the following three chains:

[0439] First chain, formula a. [GPRC5D-VH]-[CH1]-[Fc hole]

[0440] The second chain, formula b.[GPRC5D-VL]-[CL] and

[0441] The third chain, formula c.[CD3-VL]-[linker]-[CD3-VH]-[Fc knob];

[0442] Structure 2: KIH, which contains the following 4 chains:

[0443] First chain, formula a. [GPRC5D-VH]-[CH1]-[Fc hole]

[0444] The second chain, formula b.[GPRC5D-VL]-[CL]

[0445] The third chain, formula d. [CD3-VH]-[CH1]-[Fc knob] and

[0446] The fourth chain, formula e.[CD3-VL]-[CL].

[0447] Exemplary bispecific antibodies constructed are shown in Tables 8, 9 and 10.

[0448] In addition, positive controls BM03 and DuobodyBM were constructed. They were prepared based on the GCDB72 antibody disclosed in Table 23 of WO 2018017786 A2 and contain both the GPRC5D-binding portion and the CD3-binding portion of GCDB72. As a negative control, a dual antibody against Isotype CD3 (CD3-binding portion x HEL-binding portion) was prepared. Isotype CD3 is a non-targeted T cell bispecific antibody that binds only to CD3 and not to GPRC5D. The relevant sequences are shown in Tables 9 and 10.

[0449] Bispecific antibodies can be purified using standard affinity chromatography using a Protein A prepacked column. After equilibration of the column with 1× PBS at 1 mL / min, load the sample at a flow rate of 1 mL / min. Wash the column with 1× PBS at the same flow rate and collect the fraction into approximately 500 μL tubes. Read the absorbance at 280 nm using a NanoDrop instrument. Aliquot and store.

[0450] Table 8. Correspondence between anti-GPRC5D monoclonal antibodies and bispecific antibodies

[0451] Table 9. Sequence numbering of chains of GPRC5D×CD3 bispecific antibody

[0452] Table 10. Bispecific antibody sequences

[0453] Example 4: Binding activity detection of anti-GPRC5D×CD3 bispecific antibody to HEK293T_hGPRC5D cells

[0454] Flow cytometry was used to analyze the binding of bispecific antibodies (Bs71D8, Bs80A8, Bs155C2, and 80A8KIH) to HEK293T hGPRC5D cells. The viability of HEK293T hGPRC5D cells was measured and counted. Cells were aliquoted according to sample size, and staining buffer (2% FBS-PBS) was prepared. Cells were washed by centrifugation and the medium was removed. HEK293T hGPRC5D cells were then incubated with various concentrations of bispecific antibodies (initial concentration: 160 nM, with eight dilutions) at 4°C for 30 minutes. After washing the cells twice by centrifugation at 1200 rpm for 5 minutes, Goat anti-Human IgG (H+L) Cross-Adsorbed Secondary Antibody, AF488 (Invitrogen, Catalog No. A-11013, 1:1000 dilution) was added and incubated at 4°C in the dark for 30 minutes. After washing the cells twice, the cells were analyzed by flow cytometry. The results are shown in Figures 3 and 4.

[0455] The results showed that the negative control bispecific antibody, Isotype CD3, showed no significant binding to HEK293T_hGPRC5D cells. Figure 3 and Table 11A show that Bs71D8, Bs80A8, and Bs155C2 bound to HEK293T_hGPRC5D cells better than the positive control molecule, BM03. Figure 4 and Table 11B show that Bs80A8 and 80A8KIH bound to HEK293T_hGPRC5D cells better than the positive control molecule, DuobodyBM.

[0456] Table 11A. EC50 of binding of bispecific antibodies to HEK293T_hGPRC5D cells

[0457] Table 11B. EC50 of binding of bispecific antibodies to HEK293T_hGPRC5D cells

[0458] Example 5: Detection of T cell activation activity of anti-GPRC5D×CD3 bispecific antibody

[0459] MM.1R cells (MM cell line, obtained from the Shanghai Cell Bank of the Chinese Academy of Sciences) were co-incubated with Jurkat / NFAT-Luc reporter cells 4E2 (fluorescein reporter gene effector cells, homemade in the laboratory) to evaluate the ability of the anti-GPRC5D×CD3 dual antibody to induce CD3-mediated activation of Jurkat cells (human T cells) when simultaneously binding to human CD3 and human GPRC5D.

[0460] First, prepare T cell activation medium: 1640 + 10% FBS; take MM.1R cells (target cells) and 4E2 cells (effector cells) in the logarithmic growth phase, centrifuge at 1200 rpm for 5 minutes, resuspend and count, and adjust the cell density to 2×10 4 Each well was seeded in a plate; the control group was seeded with the same number of 4E2 cells and blank culture medium. Bs80A8, Bs71D8, Bs155C2, BM03, DuobodyBM, and IsotypeCD3 were diluted to a starting concentration of 80 nM, with 5 10-fold dilutions and 3 100-fold dilutions, for a total of 8 concentration points. The 96-well plate was incubated in a 37°C, 5% CO2 incubator for 6 hours and assayed using the Bio-Lite Luciferase Assay Kit. The intensity of the luminescent signal detected by the microplate reader (obtained by adding luciferase substrate) is proportional to the intensity of CD3 activation and signal transduction. The results are shown in Figures 5 and 6.

[0461] Figure 5 shows that Bs80A8, Bs71D8, Bs155C, and the positive control BM03 all induced activation of Jurkat / NFAT-Luc cells in a dose-dependent manner, while no significant activation signal was obtained in the presence of the negative control molecule, Isotype CD3. Bs80A8 had the strongest specific activation potency, followed by Bs155C2 and Bs71D8, all of which were superior to BM03. Figure 6 shows that Bs80A8 had a stronger specific activation potency than DuobodyBM.

[0462] Table 12A. T cell activation by bispecific antibodies

[0463] Table 12B. EC50 of binding of bispecific antibodies to HEK293T_hGPRC5D cells

[0464] Example 6: Detection of T cell cytotoxicity induced by anti-GPRC5D×CD3 bispecific antibody

[0465] To measure the function of the anti-GPRC5D×CD3 bispecific antibody, an in vitro LDH assay (TDCC) was used to determine T cell cytotoxicity. TDCC medium was prepared: RPMI1640 + Glutamax medium + 2% FBS + 1 nM sodium pyruvate + 1×NEAA (all reagents from Gibco). MM.1R, MM.1S, and RPMI8226 cells (all MM cell lines from the Chinese Academy of Sciences Cell Bank) in the logarithmic growth phase were centrifuged at 1200 rpm for 5 minutes, washed once with TDCC medium, and resuspended at a density of 250 cells / μL for use. A single PBMC was thawed in a 37°C water bath, centrifuged at 1200 rpm for 5 minutes, and the supernatant discarded. The cells were resuspended at a density of 2500 cells / μL for use. Dilute Bs80A8, Bs71D8, Bs155C2, BM03, DuobodyBM, and IsotypeCD3 to a starting concentration of 8 nM, and then perform a 10-fold serial dilution to obtain a total of 8 concentration points.

[0466] i. Add 120 μL TDCC medium to each well (blank well);

[0467] ii. Add 40 μL of MM cells and 80 μL of TDCC medium to each well (minimum release well);

[0468] iii. Add 40 μL of MM cells and 80 μL of TDCC medium to each well (maximum release well);

[0469] iv. 40 μL MM cells, 40 μL PBMC and 40 μL TTDCC culture medium per well (TDCC background well);

[0470] v. 40 μL MM cells, 40 μL PBMC and 40 μL diluted double antibody sample (test well) were added to each well.

[0471] The 96-well culture plate was placed in a 37°C, 5% CO2 incubator and cultured for 24 hours. The killing rate was determined using an LDH kit (Roche). In group iii (maximum release well), 5 μL / well lysis buffer was added, gently tapped to mix, and the cells were lysed at 37°C for 5 minutes. 1 mL of ultrapure water was added to the Catalyst to dissolve it, diluted 1:45 with staining solution, 100 μL / well was added to the culture plate, and incubated in the dark at room temperature for 20 minutes. The reaction was terminated with 50 μL / well stop solution. The OD value was read at a wavelength of 492 nm, and all OD values ​​were subtracted from the blank well value for data analysis. The percentage of cells lysed by TDCC was calculated according to the following formula:

[0472] Target cell lysis (%) = (OD value of the experimental group - OD value of the TDCC background well) / (OD value of the maximum release well - OD value of the minimum release well) × 100%.

[0473] The results are shown in Figures 7 to 12.

[0474] The results showed that all anti-GPRC5D×CD3 dual antibodies induced concentration-dependent lysis of the three MM cell lines, MM.1R, MM.1S, and RPMI 8226, with varying relative levels of hGPRC5D expression. Bs80A8 induced the strongest T cell cytotoxicity, followed by Bs155C2 and Bs71D8, both of which were superior to BM03. Bs80A8 also significantly outperformed the positive control DuobodyBM in cytotoxicity.

[0475] Table 13A. T cell killing activity induced by bispecific antibodies

[0476] Table 13B. T cell killing activity induced by bispecific antibodies

[0477] Example 7: Anti-tumor efficacy of bispecific antibodies in the human myeloma NCI-H929 subcutaneously transplanted female NPG mouse MiXeno model

[0478] The antitumor efficacy of the bispecific antibodies BM03, Bs80A8, and Bs155C2 was evaluated in the hGPRC5D-NCI-H929 mouse multiple myeloma tumor model. NCI-H929 cells (sourced from ATCC) were cultured in RPMI-1640 medium supplemented with 10% FBS and 0.05 mM β-ME. Cells were harvested during the exponential growth phase and resuspended at an appropriate concentration for subcutaneous tumor inoculation in female MiXeno model NPG mice (sourced from Crown Bioscience). Each mouse was inoculated subcutaneously with 5×10 cells on the right side of the back. 6 NCI-H929 cells were resuspended in 0.1 mL of 1:1 PBS and Matrigel. 5 × 10 6 PBMC / 0.1mL PBS was injected into each mouse intraperitoneally (ip) on the day of NCI-H929 cell inoculation (donor PBMC was from Miaoshun). Tumor growth was observed regularly and the tumor was kept in the same place until the average volume of the tumor reached about 115mm. 3 The mice were randomly divided into four groups. The day of grouping was defined as day 0 (day 0). On the day of grouping, mice were administered the dual antibodies BM03, Bs80A8, and Bs155C2 via intravenous infusion (iv). The vehicle control was an equal volume of PBS solution. The specific dosing schedule is shown in Table 14. The dosing cycle for this trial was from day 0 to day 18, with some groups extending the observation period to day 32. The evaluation indicators for this trial were: absolute tumor proliferation rate (T / C value, T / C) and absolute tumor growth inhibition rate (TGI), as well as other mouse health information.

[0479] T / C%=T mTV / C mTV ×100%; where T mTV : mean tumor weight of the treatment group; CmTV: mean tumor weight of the control group;

[0480] TGI%=(1-T / C)×100%; wherein T / C% is the absolute tumor growth rate, which is the percentage value of the relative tumor volume (or body weight) of the treatment group and the control group at a certain time point.

[0481] The drug was stopped on day 18. No mice died during the experiment, and the lowest weight change was -2.26% (BM03 group). Overall, the mice tolerated the drug well. The results are shown in Figure 13 and Table 14.

[0482] The results showed that the average tumor volume of the vehicle control group was 3303.18 mm on day 18. 3 The average tumor volumes of the drug-treated groups BM03, Bs80A8, and Bs155C2 were 2429.01 mm 3 , 85.62mm 3and 370.06mm 3 , their TGI were 26.46% (P=0.087), 97.41% (P<0.001) and 88.80% (P<0.001), respectively. There were significant differences in the Bs80A8 and Bs155C2 treatment groups compared with the control group and the model group, and the tumor inhibition rates of Bs80A8 and Bs155C2 were significantly better than those of BM03.

[0483] Table 14. NPG dosing regimen for mice

[0484] Table 15. Pharmacological efficacy results at the 18th day of dosing endpoint

[0485] Table 16. Encoding nucleic acid sequence information

Claims

1. An anti-GPRC5D antibody or an antigen-binding fragment thereof, comprising a heavy chain variable region and a light chain variable region; wherein: The heavy chain variable region and the light chain variable region are selected from any one of the following groups: 1) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 41; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 46; 2) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 31; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 36; 3) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 91; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 96; 4) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 21; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 26; 5) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 61; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 66; 6) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 81; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 86; 7) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 1; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 6; 8) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 11; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 16; 9) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 51; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 56; 10) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 71; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 76; 11) The heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 101; the light chain variable region comprises LCDR1, LCDR2, LCDR3; 12) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 111; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 116; 13) the heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 121; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 126; and 14) The heavy chain variable region comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 131; the light chain variable region comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 136; wherein: The amino acid sequences of the HCDR and the LCDR are determined according to the Kabat, Chothia or IMTG numbering system.

2. The anti-GPRC5D antibody or antigen-binding fragment thereof according to claim 1, wherein The heavy chain variable region and the light chain variable region are selected from any one of the following groups: 1) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 43, HCDR2 shown in SEQ ID NO: 44, and HCDR3 shown in SEQ ID NO: 45; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 48, LCDR2 shown in SEQ ID NO: 49, and LCDR3 shown in SEQ ID NO: 50; 2) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 33, HCDR2 shown in SEQ ID NO: 34, and HCDR3 shown in SEQ ID NO: 35; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 38, LCDR2 shown in SEQ ID NO: 39, and LCDR3 shown in SEQ ID NO: 40; 3) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 93, HCDR2 shown in SEQ ID NO: 94, and HCDR3 shown in SEQ ID NO: 95; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 98, LCDR2 shown in SEQ ID NO: 99, and LCDR3 shown in SEQ ID NO: 100; 4) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 23, HCDR2 shown in SEQ ID NO: 24, and HCDR3 shown in SEQ ID NO: 25; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 28, LCDR2 shown in SEQ ID NO: 29, and LCDR3 shown in SEQ ID NO: 30; 5) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 63, HCDR2 shown in SEQ ID NO: 64, and HCDR3 shown in SEQ ID NO: 65; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 68, LCDR2 shown in SEQ ID NO: 69, and LCDR3 shown in SEQ ID NO: 70; 6) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 83, HCDR2 shown in SEQ ID NO: 84, and HCDR3 shown in SEQ ID NO: 85; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 88, LCDR2 shown in SEQ ID NO: 89, and LCDR3 shown in SEQ ID NO: 90; 7) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 3, HCDR2 shown in SEQ ID NO: 4, and HCDR3 shown in SEQ ID NO: 5; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 8, LCDR2 shown in SEQ ID NO: 9, and LCDR3 shown in SEQ ID NO: 10; 8) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 13, HCDR2 shown in SEQ ID NO: 14, and HCDR3 shown in SEQ ID NO: 15; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 18, LCDR2 shown in SEQ ID NO: 19, and LCDR3 shown in SEQ ID NO: 20; 9) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 53, HCDR2 shown in SEQ ID NO: 54, and HCDR3 shown in SEQ ID NO: 55; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 58, LCDR2 shown in SEQ ID NO: 59, and LCDR3 shown in SEQ ID NO: 60; 10) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 73, HCDR2 shown in SEQ ID NO: 74, and HCDR3 shown in SEQ ID NO: 75; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 78, LCDR2 shown in SEQ ID NO: 79, and LCDR3 shown in SEQ ID NO: 80; 11) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 103, HCDR2 shown in SEQ ID NO: 104, and HCDR3 shown in SEQ ID NO: 105; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 108, LCDR2 shown in SEQ ID NO: 109, and LCDR3 shown in SEQ ID NO: 110; 12) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 113, HCDR2 shown in SEQ ID NO: 114, and HCDR3 shown in SEQ ID NO: 115; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 118, LCDR2 shown in SEQ ID NO: 119, and LCDR3 shown in SEQ ID NO: 120; 13) the heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 123, HCDR2 shown in SEQ ID NO: 124, and HCDR3 shown in SEQ ID NO: 125; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 128, LCDR2 shown in SEQ ID NO: 129, and LCDR3 shown in SEQ ID NO: 130; and 14) The heavy chain variable region comprises HCDR1 shown in SEQ ID NO: 133, HCDR2 shown in SEQ ID NO: 134, and HCDR3 shown in SEQ ID NO: 135; and the light chain variable region comprises LCDR1 shown in SEQ ID NO: 138, LCDR2 shown in SEQ ID NO: 139, and LCDR3 shown in SEQ ID NO:

140.

3. The anti-GPRC5D antibody or antigen-binding fragment thereof according to claim 1 or 2, wherein the heavy chain variable region and the light chain variable region are selected from any one of the following groups: 1) the heavy chain variable region comprises the amino acid sequence of SEQ ID NO:41 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:41, and the light chain variable region comprises the amino acid sequence of SEQ ID NO:46 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:46; 2) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:31 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:31, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:36 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:36; 3) The heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 91 or comprises the amino acid sequence shown in SEQ ID NO: 91, and the light chain variable region comprises an amino acid sequence of SEQ ID NO:96 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:96; 4) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:21 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:21, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:26 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:26; 5) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:61 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:61, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:66 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:66; 6) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:81 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:81, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:86 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:86; 7) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:1 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:1, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:6 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:6; 8) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:11 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:11, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:16 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:16; 9) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:51 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:51, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:56 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:56; 10) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:71 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:71, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:76 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:76; 11) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:101, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:101, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:106, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:106; 12) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:111, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:111, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:116, or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:116; 13) the heavy chain variable region comprises the amino acid sequence set forth in SEQ ID NO:121 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:121, and the light chain variable region comprises the amino acid sequence set forth in SEQ ID NO:126 or an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:126; and 14) The heavy chain variable region comprises the amino acid sequence shown in SEQ ID NO: 131 or comprises the amino acid sequence shown in SEQ ID NO: The light chain variable region comprises an amino acid sequence of SEQ ID NO: 136 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:

136.

4. The anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 3, wherein the anti-GPRC5D antibody or antigen-binding fragment thereof is a humanized antibody or antigen-binding fragment thereof, a fully human antibody or antigen-binding fragment thereof, or a chimeric antibody or antigen-binding fragment thereof.

5. The anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 4, wherein the antigen-binding fragment is selected from any one of the following: Fab, scFv, Fv, Fab', F(ab')2, single domain antibody, scFab, linear antibody and multispecific antibody.

6. The anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 5, further comprising a heavy chain constant region and a light chain constant region, wherein the heavy chain constant region is selected from human IgG1, human IgG2, human IgG3 and human IgG4, and the light chain constant region is selected from λ and κ light chain constant regions; preferably, the heavy chain constant region comprises the amino acid sequence of SEQ ID NO: 143, and the light chain constant region comprises the amino acid sequence of SEQ ID NO:

144.

7. The anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 6, wherein the anti-GPRC5D antibody comprises a member selected from any one of the following groups: 1) the heavy chain comprises the amino acid sequence as shown in SEQ ID NO: 149 or comprises an amino acid sequence having at least 85% sequence identity with SEQ ID NO: 149, and the light chain comprises the amino acid sequence as set forth in SEQ ID NO:150, or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:150; 2) the heavy chain comprises the amino acid sequence as shown in SEQ ID NO: 147 or comprises an amino acid sequence having at least 85% sequence identity with SEQ ID NO: 147, and the light chain comprises the amino acid sequence set forth in SEQ ID NO:148, or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:148; 3) the heavy chain comprises the amino acid sequence as shown in SEQ ID NO: 155 or comprises an amino acid sequence having at least 85% sequence identity with SEQ ID NO: 155, and the light chain comprises the amino acid sequence set forth in SEQ ID NO:156, or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:156; 4) the heavy chain comprises the amino acid sequence as shown in SEQ ID NO: 145 or comprises an amino acid sequence having at least 85% sequence identity with SEQ ID NO: 145, and the light chain comprises the amino acid sequence set forth in SEQ ID NO:146, or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:146; 5) the heavy chain comprises the amino acid sequence as shown in SEQ ID NO: 151 or comprises an amino acid sequence having at least 85% sequence identity with SEQ ID NO: 151, and The light chain comprises the amino acid sequence as set forth in SEQ ID NO: 152 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 152; and 6) the heavy chain comprises the amino acid sequence as shown in SEQ ID NO: 153 or comprises an amino acid sequence having at least 85% sequence identity with SEQ ID NO: 153, and The light chain comprises the amino acid sequence as shown in SEQ ID NO:154 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:

154.

8. A bispecific antibody comprising: - at least one first binding moiety that specifically binds to GPRC5D, and - at least one second binding moiety that specifically binds to CD3; The first binding portion that specifically binds to GPRC5D comprises a heavy chain variable region GPRC5D-VH and a light chain variable region GPRC5D-VL, wherein, The GPRC5D-VH and the GPRC5D-VL are selected from any one of the following groups: 1) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 41; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 46; 2) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 31; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 36; 3) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 91; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 96; 4) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 21; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 26; 5) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 61; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 66; 6) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 81; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 86; 7) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 1; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 6; 8) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 11; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 16; 9) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 51; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 56; 10) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 71; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 76; 11) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 101; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 106; 12) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 111; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 116; 13) the GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 of the sequence shown in SEQ ID NO: 121; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 of the sequence shown in SEQ ID NO: 126; 14) The GPRC5D-VH comprises HCDR1, HCDR2, and HCDR3 in the sequence shown in SEQ ID NO: 131; the GPRC5D-VL comprises LCDR1, LCDR2, and LCDR3 in the sequence shown in SEQ ID NO: 136; wherein: The amino acid sequences of the HCDR and the LCDR are determined according to the Kabat, Chothia or IMTG numbering system; Preferably, the GPRC5D-VH and the GPRC5D-VL are selected from any one of the following groups: 1) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 43, HCDR2 shown in SEQ ID NO: 44, and HCDR3 shown in SEQ ID NO: 45; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 48, LCDR2 shown in SEQ ID NO: 49, and LCDR3 shown in SEQ ID NO: 50; 2) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 33, HCDR2 shown in SEQ ID NO: 34, and HCDR3 shown in SEQ ID NO: 35; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 38, LCDR2 shown in SEQ ID NO: 39, and LCDR3 shown in SEQ ID NO: 40; 3) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 93, HCDR2 shown in SEQ ID NO: 94, and HCDR3 shown in SEQ ID NO: 95; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 98, LCDR2 shown in SEQ ID NO: 99, and LCDR3 shown in SEQ ID NO: 100; 4) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 23, HCDR2 shown in SEQ ID NO: 24, and HCDR3 shown in SEQ ID NO: 25; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 28, LCDR2 shown in SEQ ID NO: 29, and LCDR3 shown in SEQ ID NO: 30; 5) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 63, HCDR2 shown in SEQ ID NO: 64, and HCDR3 shown in SEQ ID NO: 65; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 68, LCDR2 shown in SEQ ID NO: 69, and LCDR3 shown in SEQ ID NO: 70; 6) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 83, HCDR2 shown in SEQ ID NO: 84, and HCDR3 shown in SEQ ID NO: 85; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 88, LCDR2 shown in SEQ ID NO: 89, and LCDR3 shown in SEQ ID NO: 90; 7) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 3, HCDR2 shown in SEQ ID NO: 4, and HCDR3 shown in SEQ ID NO: 5; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 8, LCDR2 shown in SEQ ID NO: 9, and LCDR3 shown in SEQ ID NO: 10; 8) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 13, HCDR2 shown in SEQ ID NO: 14, and HCDR3 shown in SEQ ID NO: 15; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 18, LCDR2 shown in SEQ ID NO: 19, and LCDR3 shown in SEQ ID NO: 20; 9) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 53, HCDR2 shown in SEQ ID NO: 54, and HCDR3 shown in SEQ ID NO: 55; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 58, LCDR2 shown in SEQ ID NO: 59, and LCDR3 shown in SEQ ID NO: 60; 10) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 73, HCDR2 shown in SEQ ID NO: 74, and HCDR3 shown in SEQ ID NO: 75; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 78, LCDR2 shown in SEQ ID NO: 79, and LCDR3 shown in SEQ ID NO: 80; 11) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 103, HCDR2 shown in SEQ ID NO: 104, and HCDR3 shown in SEQ ID NO: 105; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 108, LCDR2 shown in SEQ ID NO: 109, and LCDR3 shown in SEQ ID NO: 110; 12) the GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 113, HCDR2 shown in SEQ ID NO: 114, and HCDR3 shown in SEQ ID NO: 115; and the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 118, LCDR2 shown in SEQ ID NO: 119, and LCDR3 shown in SEQ ID NO: 120; 13) The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 123, SEQ ID NO: 124, HCDR2, SEQ ID NO: 125; and the GPRC5D-VL comprises LCDR1, SEQ ID NO: 128, LCDR2, SEQ ID NO: 129, and LCDR3, SEQ ID NO: 130; and 14) The GPRC5D-VH comprises HCDR1 shown in SEQ ID NO: 133, HCDR2 shown in SEQ ID NO: 134, and HCDR3 shown in SEQ ID NO: 135; the GPRC5D-VL comprises LCDR1 shown in SEQ ID NO: 138, LCDR2 shown in SEQ ID NO: 139, and LCDR3 shown in SEQ ID NO:

140.

9. The bispecific antibody according to claim 8, wherein the GPRC5D-VH and the GPRC5D-VL are selected from any one of the following groups: 1) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:41 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:41, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:46 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:46; 2) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:31 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:31, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:36 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:36; 3) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:91 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:91, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:96 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:96; 4) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:21 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:21, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:26 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:26; 5) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:61 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:61, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:66 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:66; 6) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:81 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:81, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:86 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:86; 7) GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 1 or comprises an amino acid sequence having at least 85% sequence identity with SEQ ID NO: 1, and GPRC5D-VL comprises SEQ ID NO: 6 or an amino acid sequence comprising an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 6; 8) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO: 11 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 11, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO: 16 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 16; 9) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:51 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:51, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:56 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO:56; 10) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO:71 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:71, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO:76 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO:76; 11) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO: 101 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 101, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO: 106 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 106; 12) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO: 111 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 111, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO: 116 or comprises an amino acid sequence that has at least 85% sequence identity to SEQ ID NO: 116; 13) GPRC5D-VH comprises the amino acid sequence set forth in SEQ ID NO: 121 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 121, and GPRC5D-VL comprises the amino acid sequence set forth in SEQ ID NO: 126 or comprises an amino acid sequence having at least 85% sequence identity to SEQ ID NO: 126; and 14) GPRC5D-VH comprises the amino acid sequence shown in SEQ ID NO: 131 or an amino acid sequence having at least 85% sequence identity with SEQ ID NO: 131, and GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 136 or an amino acid sequence having at least 85% sequence identity with SEQ ID NO:

136.

10. The bispecific antibody according to claim 8 or 9, wherein the second binding portion that specifically binds to CD3 comprises a heavy chain variable region CD3-VH and a light chain variable region CD3-VL, wherein, The CD3-VH comprises HCDR1 of SEQ ID NO: 204, HCDR2 of SEQ ID NO: 205, and HCDR3 of SEQ ID NO: 206; and the CD3-VL comprises LCDR1 of SEQ ID NO: 207, LCDR2 of SEQ ID NO: 208, and LCDR3 of SEQ ID NO: 209; More preferably, the CD3-VH comprises the amino acid sequence shown in SEQ ID NO: 202, and the CD3-VL comprises the amino acid sequence shown in SEQ ID NO:

203.

11. The bispecific antibody according to any one of claims 8 to 10, wherein the bispecific antibody further comprises an Fc region, the Fc region comprising a first subunit Fc1 and a second subunit Fc2, the Fc1 and Fc2 each independently having one or more amino acid substitutions that reduce homodimerization of the Fc region; preferably, the Fc1 has a hole structure according to the knob-in-hole technique, and the Fc2 has a protrusion structure according to the knob-in-hole technique; more preferably, the amino acid at position 366 of the Fc1 is S, the amino acid at position 368 is A, and the amino acid at position 407 is V, and the amino acid at position 366 of the Fc2 is W; the numbering is based on the EU index; most preferably, the Fc1 has the amino acid sequence shown in SEQ ID NO: 199, and the Fc2 has the amino acid sequence shown in SEQ ID NO: 197 or 198.

12. The bispecific antibody according to any one of claims 8 to 11, wherein: The first binding moiety that specifically binds to GPRC5D is Fab, and the second binding moiety that specifically binds to CD3 is scFv; or The first binding moiety that specifically binds to GPRC5D is scFv, and the second binding moiety that specifically binds to CD3 is Fab; or The first binding moiety that specifically binds to GPRC5D is Fab, and the second binding moiety that specifically binds to CD3 is Fab.

13. The bispecific antibody according to any one of claims 8 to 12, comprising: i) a first chain represented by formula a, a second chain represented by formula b, and a third chain represented by formula c; Formula a: [GPRC5D-VH]-[CH1]-[Fc1]; Formula b: [GPRC5D-VL]-[CL]; and Formula c: [CD3-VL]-[Linker]-[CD3-VH]-[Fc2]; or ii) a first chain represented by formula a, a second chain represented by formula b, a third chain represented by formula d, and a fourth chain represented by formula e: Formula a: [GPRC5D-VH]-[CH1]-[Fc1]; Formula b: [GPRC5D-VL]-[CL]; Formula d: [CD3-VH]-[CH1]-[Fc2]; and Formula e: [CD3-VL]-[CL]; wherein: The structures shown in formula a, formula b, formula c, formula d and formula e are arranged from the N-terminus to the C-terminus; The Fc1 and the Fc2 are interchangeable; The linker is a peptide linker; The GPRC5D-VH and the GPRC5D-VL are as defined in claim 8 or 9; The CD3-VH and the CD3-VL are as defined in claim 10; Preferably, The GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 41, and the GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 46; or The GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 31, and the GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 36; or The GPRC5D-VH comprises the amino acid sequence of SEQ ID NO: 91, and the GPRC5D-VL comprises the amino acid sequence of SEQ ID NO: 96; and The CD3-VH comprises the amino acid sequence of SEQ ID NO: 202, and the CD3-VL comprises the amino acid sequence of SEQ ID NO: 203; More preferably, the peptide linker has a structure of (GGGGS)n, wherein n is an integer from 1 to 8. Most preferably, the amino acid sequence of the peptide linker is as shown in SEQ ID NO:

200.

14. The bispecific antibody according to any one of claims 8 to 13, comprising a member selected from the group consisting of: 1) comprising a first strand as shown in SEQ ID NO: 165, a second strand as shown in SEQ ID NO: 167, and a third strand as shown in SEQ ID NO: 159; 2) comprising a first strand as shown in SEQ ID NO: 161, a second strand as shown in SEQ ID NO: 163, and a third strand as shown in SEQ ID NO: 159; 3) comprising a first chain shown in SEQ ID NO: 169, a second chain shown in SEQ ID NO: 171, and a third chain shown in SEQ ID NO: 159; and 4) comprising the first chain shown by SEQ ID NO: 173, the second chain shown by SEQ ID NO: 175, the third chain shown by SEQ ID NO: 177, and the fourth chain shown by SEQ ID NO:

179.

15. A pharmaceutical composition comprising: 1) a therapeutically effective amount of the anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 7, or a therapeutically effective amount of the bispecific antibody according to any one of claims 8 to 14, and 2) One or more pharmaceutically acceptable carriers, diluents, buffers or excipients.

16. An isolated nucleic acid encoding: The anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 7, or the bispecific antibody according to any one of claims 8 to 14; Preferably, the nucleic acid is selected from any one of the following groups: 1) The nucleic acid comprises the sequences shown in SEQ ID NO: 42 and SEQ ID NO: 47; 2) the nucleic acid comprises the sequences shown in SEQ ID NO: 32 and SEQ ID NO: 37; 3) the nucleic acid comprises the sequences shown in SEQ ID NO: 92 and SEQ ID NO: 97; 4) the nucleic acid comprises the sequences shown in SEQ ID NO: 22 and SEQ ID NO: 27; 5) The nucleic acid comprises the sequences shown in SEQ ID NO: 62 and SEQ ID NO: 67; 6) The nucleic acid comprises the sequences shown in SEQ ID NO: 82 and SEQ ID NO: 87; 7) The nucleic acid comprises the sequences shown in SEQ ID NO: 2 and SEQ ID NO: 7; 8) The nucleic acid comprises the sequences shown in SEQ ID NO: 12 and SEQ ID NO: 17; 9) The nucleic acid comprises the sequences shown in SEQ ID NO: 52 and SEQ ID NO: 57; 10) The nucleic acid comprises the sequences shown in SEQ ID NO: 72 and SEQ ID NO: 77; 11) The nucleic acid comprises the sequences shown in SEQ ID NO: 102 and SEQ ID NO: 107; 12) The nucleic acid comprises the sequences shown in SEQ ID NO: 112 and SEQ ID NO: 117; 13) The nucleic acid comprises the sequences shown in SEQ ID NO: 122 and SEQ ID NO: 127; and 14) The nucleic acid comprises the sequences shown in SEQ ID NO: 132 and SEQ ID NO: 137; or The nucleic acid is selected from any one of the following groups: 1) The nucleic acid comprises the sequences shown in SEQ ID NO: 160, SEQ ID NO: 166 and SEQ ID NO: 168; 2) the nucleic acid comprises the sequences shown in SEQ ID NO: 160, SEQ ID NO: 162 and SEQ ID NO: 164; 3) the nucleic acid comprises the sequences shown in SEQ ID NO: 160, SEQ ID NO: 170 and SEQ ID NO: 172; and 4) The nucleic acid comprises the sequences shown in SEQ ID NO: 174, SEQ ID NO: 176, SEQ ID NO: 178 and SEQ ID NO:

180.

17. An expression vector, which expresses: The anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 7, or the bispecific antibody according to any one of claims 8 to 14.

18. A host cell comprising: The isolated nucleic acid of claim 16, or The vector of claim 17.

19. A method for treating a disease, comprising administering to a subject a preventive or therapeutically effective amount of any of the following: The anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 7, The bispecific antibody according to any one of claims 8 to 14, The pharmaceutical composition according to claim 15, or The nucleic acid according to claim 16; The disease is cancer or an autoimmune disease; More preferably, the disease is selected from the group consisting of: multiple myeloma, Waldenstrom's macroglobulinemia, endometrial cancer, ovarian cancer, lung cancer, gastric cancer, prostate cancer, kidney cancer, liver cancer, pancreatic cancer, colorectal cancer, esophageal cancer, bladder cancer, cervical cancer, blood cancer, lymphoma and malignant melanoma; Most preferably, the disease is associated with abnormal expression of GPRC5D protein.

20. A method for inhibiting the growth or proliferation of cancer cells, the method comprising administering a therapeutically effective amount of any of the following: The anti-GPRC5D antibody or antigen-binding fragment thereof according to any one of claims 1 to 7, The bispecific antibody according to any one of claims 8 to 14, The pharmaceutical composition according to claim 15, or The nucleic acid of claim 16, to inhibit the growth or proliferation of cancer cells; Preferably, the cancer is selected from the group consisting of: multiple myeloma, Waldenstrom's macroglobulinemia, endometrial cancer, ovarian cancer, lung cancer, gastric cancer, prostate cancer, kidney cancer, liver cancer, pancreatic cancer, colorectal cancer, esophageal cancer, bladder cancer, cervical cancer, blood cancer, lymphoma and malignant melanoma; Most preferably, the cancer is associated with aberrant expression of GPRC5D protein.

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