Pharmaceutical composition for treating and / or preventing cancer

Abstract

In the present invention, by linking dolastatin 10 or a derivative thereof to an antibody or fragment thereof having immunological reactivity with CAPRIN-1 protein having an amino acid sequence shown in any one of the even numbered SEQ ID NOs: 2 to 30 or an amino acid sequence having 80% or more sequence identity with such amino acid sequence, the anti-tumoral effect by such antibody or such fragment thereof is enhanced.

Description

Pharmaceutical composition for treating and / or preventing cancer

[0001] The present invention relates to a conjugate of an antibody against CAPRIN-1 protein with dolastatin 10 or a derivative thereof, and a medical use thereof for treating and / or preventing cancer.

[0002] Various antibody drugs targeting specific antigen proteins on cancer cells have been applied to cancer treatment as cancer therapeutic drugs with few side effects due to their cancer specificity. For example, cytopasmic-activation and proliferation-associated protein 1 (CAPRIN-1) is expressed on the cell membrane surface of many solid cancers, and antibodies against this CAPRIN-1 protein are known to be promising pharmaceuticals for the treatment and / or prevention of cancer (Patent Document 1).

[0003] Dolastatin 10 is an antitumor pentapeptide that inhibits cell mitosis by inhibiting microtubule polymerization, and was isolated from the Indian Ocean shellfish (Dolabella auricularia) (Non-Patent Document 1). After dolastatin 10 was obtained and its structure was elucidated, many dolastatin 10 derivatives with antitumor properties were synthesized, and some dolastatin derivatives have been developed as chemotherapeutic agents for cancer and have been put to practical use.

[0004] In recent years, studies have been made to enhance the efficacy of antibody drugs against cancer, and in particular, the development of antibody-drug conjugates (ADCs), which conjugate antibodies with drugs that have strong direct cell killing capabilities, has been actively pursued (Non-Patent Documents 2 and 3). Although there have been few successful examples of ADCs using dolastatin 10 derivatives, PADCEV (registered trademark) (Enfortumab vedotin-ejfv), in which MMAE, a dolastatin 10 derivative, is linked to an antibody against Nectin-4, has achieved a response rate of 50% or more against cisplatin-refractory advanced or metastatic urothelial carcinoma (Non-Patent Document 4).

[0005] WO2010 / 016526

[0006] Springer Chemistry 1997 (ISSN0071-7886) Lancet Oncol. 2016;17:e256-62Pharm Res. 2015 Nov;32(11):3526-40Ther. Adv. Urol. 2020 vol. 12:1-10

[0007] As mentioned above, although ADCs using derivatives of dolastatin 10 have already been put to practical use, there have been limited success stories, and no antitumor effect sufficient to completely regress various cancers has been obtained.

[0008] Therefore, an object of the present invention is to enhance the antitumor effect of ADCs that utilize dolastatin 10 or derivatives thereof.

[0009] As a result of intensive research, the present inventors have discovered that a conjugate of an antibody against CAPRIN-1 protein or a fragment thereof with dolastatin 10 or a derivative thereof exhibits an extremely strong antitumor effect compared to an antibody against CAPRIN-1 protein or a fragment thereof alone, and further that the enhancement of the antitumor effect when dolastatin 10 or a derivative thereof is conjugated to an antibody against CAPRIN-1 protein or a fragment thereof is significantly superior to the enhancement of the antitumor effect when dolastatin 10 or a derivative thereof is conjugated to an existing cancer antibody pharmaceutical, thereby completing the present invention.

[0010] Specifically, the present invention has the following features (1) to (14).

[0011] (1) A conjugate comprising an antibody or a fragment thereof immunologically reactive with a CAPRIN-1 protein having an amino acid sequence represented by any of the even-numbered SEQ ID NOs: 2 to 30, or an amino acid sequence having 80% or more sequence identity with said amino acid sequence, and dolastatin 10 or a derivative thereof bound thereto.

[0012] (2) The conjugate according to (1), wherein the antibody or a fragment thereof is immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having an amino acid sequence represented by any one of SEQ ID NOs: 31 to 35, 296 to 299, 308, and 309, or an amino acid sequence having 80% or more sequence identity to said amino acid sequence.

[0013] (3) The conjugate according to (1) or (2), wherein the antibody is a monoclonal antibody or a polyclonal antibody.

[0014] (4) The conjugate according to any one of (1) to (3), wherein the antibody or fragment thereof is any one of the following (A) to (M): (A) an antibody or fragment comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 36, 37, and 38 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 40, 41, and 42 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with CAPRIN-1 protein; (B) an antibody or fragment comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 44, 45, and 46 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 48, 49, and 50 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with CAPRIN-1 protein. (C) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 52, 53, and 54 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 56, 57, and 58 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with the CAPRIN-1 protein. (D) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 60, 61, and 62 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 64, 65, and 66 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with the CAPRIN-1 protein. (E) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 170, 171, and 172 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 173, 174, and 175 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with CAPRIN-1 protein. (F) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 176, 177, and 178 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 179, 180, and 181 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with CAPRIN-1 protein.(G) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 182, 183, and 184 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 185, 186, and 187 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with CAPRIN-1 protein. (H) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 188, 189, and 190 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 191, 192, and 193 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with CAPRIN-1 protein. (I) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 146, 147, and 148 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 149, 150, and 151 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with CAPRIN-1 protein. (J) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 272, 273, and 274 (CDR1, CDR2, and CDR3, respectively), and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 275, 276, and 277 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with CAPRIN-1 protein. (K) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions (CDR1, CDR2 and CDR3, respectively) of SEQ ID NOs: 290, 291 and 292 and a light chain variable region comprising the complementarity determining regions (CDR1, CDR2 and CDR3, respectively) of SEQ ID NOs: 293, 294 and 295, and having immunological reactivity with the CAPRIN-1 protein. (L) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions (CDR1, CDR2 and CDR3, respectively) of SEQ ID NOs: 301, 302 and 303 and a light chain variable region comprising the complementarity determining regions (CDR1, CDR2 and CDR3, respectively) of SEQ ID NOs: 305, 306 and 307, and having immunological reactivity with the CAPRIN-1 protein.(M) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 134, 135, and 136, respectively, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 137, 138, and 139, respectively, and having immunological reactivity with a CAPRIN-1 protein.

[0015] (5) The conjugate according to any one of (1) to (4), wherein the antibody or fragment thereof is any one of the following (a) to (a1): (a) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 39 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 43; (b) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 47 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 51; (c) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 55 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 59; (d) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 63 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 67; (e) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 68 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 69; (f) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 70 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 71. (g) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 72 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 73; (h) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 74 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 75; (i) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 76 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 77; (j) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 78 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 79; (k) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 80 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 81; (l) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 82 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 83. (m) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 84 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 85.(n) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 86 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 87; (o) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 88 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 89; (p) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 90 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 91; (q) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 92 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 93; (r) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 94 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 95; (s) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 96 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 97. (t) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 98 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 99; (u) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 100 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 101; (v) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 102 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 103; (w) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 104 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 105; (x) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 106 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 107; (y) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 108 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 109. (z) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 110 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 111; (aa) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 112 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 113.(ab) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 114 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 115; (ac) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 116 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 117; (ad) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 118 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 119; (ae) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 120 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 121; (af) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 122 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 123; (ag) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 124 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 125. (ah) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 126 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 127; (ai) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 128 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 129; (aj) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 130 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 131; (ak) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 132 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 133; (al) an antibody or fragment thereof, whose heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 300 and whose light chain variable region comprises the amino acid sequence of SEQ ID NO: 304.

[0016] (6) The conjugate according to any one of (1) to (5), wherein the antibody is a human antibody, a humanized antibody, a chimeric antibody, or a single-chain antibody.

[0017] (7) The conjugate according to any one of (1) to (6), wherein the antibody or fragment thereof and dolastatin 10 or a derivative thereof are bound via a linker.

[0018] (8) The conjugate according to any one of (1) to (7), wherein the dolastatin 10 derivative is monomethyl auristatin E (MMAE), monomethyl auristatin F (MMAF), or a derivative thereof.

[0019] (9) A pharmaceutical composition for treating and / or preventing cancer, comprising the conjugate according to any one of (1) to (8) as an active ingredient.

[0020] (10) The pharmaceutical composition according to (9), further comprising one or more antitumor agents, either together or separately.

[0021] (11) The pharmaceutical composition according to (9) or (10), wherein the cancer expresses CAPRIN-1 protein on the cell membrane surface.

[0022] (12) The pharmaceutical composition according to any one of (9) to (11), wherein the cancer is breast cancer, kidney cancer, pancreatic cancer, colon cancer, lung cancer, brain tumor, stomach cancer, uterine cancer, ovarian cancer, prostate cancer, bladder cancer, esophageal cancer, leukemia, lymphoma, liver cancer, gallbladder cancer, bile duct cancer, sarcoma, mast cell tumor, melanoma, adrenocortical carcinoma, Ewing's tumor, Hodgkin's lymphoma, mesothelioma, multiple myeloma, testicular cancer, thyroid cancer, head and neck cancer, urothelial carcinoma, renal cell carcinoma, colorectal cancer, gastroesophageal junction cancer, hepatocellular carcinoma, glioblastoma, primary central nervous system lymphoma, primary testicular lymphoma, biliary tract cancer, sarcoma, fibrosarcoma, basal cell carcinoma, Paget's disease, or skin cancer.

[0023] (13) A method for treating and / or preventing cancer, comprising administering the conjugate according to any one of (1) to (8) to a subject.

[0024] (14) A method for treating and / or preventing cancer, comprising administering to a subject a combination of the conjugate according to any one of (1) to (8) and one or more antitumor agents, together or separately.

[0025] The conjugate of the present invention not only exhibits an extremely strong antitumor effect compared to an antibody against CAPRIN-1 protein or a fragment thereof alone, but also has a significantly superior antitumor effect than conjugates of previously known cancer antibody drugs with dolastatin 10 or a derivative thereof. Furthermore, the enhancement of the antitumor effect achieved by conjugating dolastatin 10 or a derivative thereof to an antibody against CAPRIN-1 protein or a fragment thereof is significantly superior to the enhancement of the antitumor effect achieved by conjugating dolastatin 10 or a derivative thereof to an existing cancer antibody drug. Therefore, the conjugate of the present invention is effective in treating or preventing cancer.

[0026] The antitumor activity of a conjugate of an antibody against the CAPRIN-1 protein or a fragment thereof (hereinafter referred to as an "anti-CAPRIN-1 antibody") used in the present invention with dolastatin 10 or a derivative thereof can be evaluated by examining the inhibition of tumor growth in tumor-bearing animals in vivo, as described below.

[0027] In the present invention, the term "conjugate" refers to a compound in which an antibody and dolastatin 10 or a derivative thereof are linked by a covalent bond. The antibody and dolastatin 10 or a derivative thereof may be linked via a linker.

[0028] The anti-CAPRIN-1 antibody forming the conjugate of the present invention may be a monoclonal or polyclonal antibody, preferably a monoclonal antibody. The conjugate of the present invention may be any type of antibody, including a recombinant antibody, a human antibody, a humanized antibody, a chimeric antibody, or a non-human animal antibody, as long as it can exhibit antitumor activity.

[0029] Dolastatin 10 or a derivative thereof forming the conjugate according to the present invention is known as one of the substances that is toxic to cancer cells by directly acting on microtubules to inhibit microtubule formation or mitosis.

[0030] Furthermore, subjects for cancer treatment and / or prevention in the present invention include mammals such as humans, pet animals, livestock, and sport animals, with humans being the preferred subject.

[0031] The following describes the anti-CAPRIN-1 antibody, dolastatin 10 or a derivative thereof, a conjugate of an anti-CAPRIN-1 antibody and dolastatin 10 or a derivative thereof, a pharmaceutical composition using the conjugate, and a method for treating and / or preventing cancer according to the present invention.

[0032] <Anti-CAPRIN-1 Antibody> Among CAPRIN-1 proteins having an amino acid sequence represented by any of the even-numbered SEQ ID NOS: 2 to 30, which are immunologically reactive with the anti-CAPRIN-1 antibody used in the present invention, the amino acid sequences represented by SEQ ID NOS: 6, 8, 10, 12, and 14 are the amino acid sequences of canine CAPRIN-1 protein, the amino acid sequences represented by SEQ ID NOS: 2 and 4 are the amino acid sequences of human CAPRIN-1 protein, the amino acid sequence represented by SEQ ID NOS: 16 is the amino acid sequence of bovine CAPRIN-1 protein, the amino acid sequence represented by SEQ ID NOS: 18 is the amino acid sequence of equine CAPRIN-1 protein, the amino acid sequences represented by SEQ ID NOS: 20 to 28 are the amino acid sequences of mouse CAPRIN-1 protein, and the amino acid sequence represented by SEQ ID NOS: 30 is the amino acid sequence of chicken CAPRIN-1 protein.

[0033] Furthermore, the anti-CAPRIN-1 antibody used in the present invention may be immunologically reactive with a variant of the CAPRIN-1 protein having 80% or more, preferably 90% or more, more preferably 95% or more, and even more preferably 99% or more sequence identity with the amino acid sequence represented by any of the even-numbered SEQ ID NOs: 2 to 30. As used herein, "% sequence identity" refers to the percentage (%) of identical amino acids (or bases) relative to the total number of amino acids (or bases) when the two sequences are aligned to maximize similarity, with or without introducing gaps.

[0034] In the present invention, the anti-CAPRIN-1 antibody used to prepare a conjugate refers to an antibody or a fragment thereof that is immunologically reactive with the full-length CAPRIN-1 protein or a fragment thereof. Here, "immunological reactivity" refers to the property of the antibody binding to the CAPRIN-1 protein or a partial polypeptide thereof in vivo.

[0035] The anti-CAPRIN-1 antibody used in the present invention may be a monoclonal antibody or a polyclonal antibody.

[0036] Polyclonal antibodies immunologically reactive with the full-length CAPRIN-1 protein or a fragment thereof (anti-CAPRIN-1 polyclonal antibodies) can be obtained by immunizing mice, human antibody-producing mice, rats, rabbits, chickens, or the like with, for example, the natural CAPRIN-1 protein, a fusion protein with GST or the like, or a partial peptide thereof, and then obtaining serum. The obtained serum can be purified by ammonium sulfate precipitation, protein A, protein G, DEAE ion exchange column, affinity column to which the CAPRIN-1 protein or a partial peptide is bound, or the like.

[0037] The full-length CAPRIN-1 protein or a fragment thereof used in the immunization, the nucleotide sequence and amino acid sequence of CAPRIN-1 and its homologs, can be obtained, for example, by accessing GenBank (NCBI, USA) and using algorithms such as BLAST and FASTA (Karlin and Altschul, Proc. Natl. Acad. Sci. USA, 90: 5873-5877, 1993; Altschul et al., Nucleic Acids Res. 25: 3389-3402, 1997). In addition, a method for producing the CAPRIN-1 protein can be obtained by referring to WO2014 / 012479, and cells expressing the CAPRIN-1 protein can also be used.

[0038] A monoclonal antibody immunologically reactive with the full-length CAPRIN-1 protein or a fragment thereof (anti-CAPRIN-1 monoclonal antibody) can be obtained, for example, by immunizing a mouse with SK-BR-3 breast cancer cells expressing CAPRIN-1 or the full-length CAPRIN-1 protein or a fragment thereof, fusing spleen cells isolated from the mouse with myeloma cells, and selecting a clone producing an anti-CAPRIN-1 monoclonal antibody from the resulting fused cells (hybridoma). The antibody produced by the selected hybridoma can be obtained by a method similar to the method for purifying polyclonal antibodies described above.

[0039] The antibodies used in the present invention include human antibodies, humanized antibodies, chimeric antibodies, and non-human animal antibodies.

[0040] Human antibodies can be obtained by sensitizing human lymphocytes infected with EB virus with a protein, protein-expressing cells, or a lysate thereof, fusing the sensitized lymphocytes with myeloma cells such as human-derived U266 cells, and then obtaining antibodies immunologically reactive with the full-length CAPRIN-1 protein or a fragment thereof from the resulting fused cells.

[0041] A humanized antibody is a modified antibody, also known as a reshaped human antibody. Humanized antibodies are constructed by grafting the complementarity-determining regions (CDRs) of an antibody derived from an immunized animal onto the CDRs of a human antibody. Genetic recombination, a common technique for this purpose, is well known. Specifically, for example, a DNA sequence designed to link the CDRs of a mouse or rabbit antibody with the framework regions of a human antibody is synthesized by PCR from several oligonucleotides engineered to have overlapping ends. The resulting DNA is ligated to DNA encoding the constant regions of a human antibody, incorporated into an expression vector, and then introduced into a host for production (see EP 239400 and WO 96 / 02576). The framework regions of the human antibody linked via the CDRs are selected so that the CDRs form a good antigen-binding site. If necessary, amino acids in the framework regions of the variable regions of the antibody may be substituted so that the complementarity-determining regions of the reshaped human antibody form an appropriate antigen-binding site (Sato K. et al., Cancer Research 1993, 53:851-856). Alternatively, they may be substituted with framework regions derived from various human antibodies (see WO99 / 51743).

[0042] Antibodies are typically heteromeric glycoproteins containing at least two heavy chains and two light chains. Antibodies consist of two identical light chains and two identical heavy chains. Heavy chains have a heavy chain variable region at one end, followed by several constant regions. Light chains have a light chain variable region at one end, followed by several constant regions. The variable regions exhibit specific variable regions called complementarity-determining regions (CDRs) that confer binding specificity to the antibody. Portions of the variable regions that are relatively conserved are called framework regions (FRs). Complete heavy and light chain variable regions each contain four FRs connected by three CDRs (CDR1 to CDR3).

[0043] The sequences of the constant and variable regions of human-derived heavy and light chains are available from NCBI (USA: GenBank, UniGene, etc.). For example, reference can be made to the sequences of the human IgG1 heavy chain constant region under accession number J00228, the human IgG2 heavy chain constant region under accession number J00230, the human light chain κ constant region under accession numbers V00557, X64135, X64133, etc., and the human light chain λ constant region under accession numbers X64132, X64134, etc.

[0044] A chimeric antibody is an antibody produced by combining sequences derived from different animals, such as an antibody consisting of a heavy chain variable region and a light chain variable region of a mouse antibody and a heavy chain constant region and a light chain constant region of a human antibody. Chimeric antibodies can be produced using known methods, for example, by linking DNA encoding an antibody V region with DNA encoding a human antibody C region, incorporating the resultant into an expression vector, and introducing the vector into a host for production.

[0045] Non-human animal antibodies can be obtained by immunizing an animal with a sensitizing antigen according to known methods. A typical method is to inject the sensitizing antigen intraperitoneally, intradermally, or subcutaneously into an animal such as a mouse. When injecting the sensitizing antigen, the antigen is mixed with an appropriate amount of various adjuvants, such as Freund's complete adjuvant (CFA), and administered to the animal multiple times. After immunizing an animal and confirming that the serum contains anti-CAPRIN-1 antibodies, the serum can be obtained and purified, as described above, by ammonium sulfate precipitation, protein A, protein G, DEAE ion exchange columns, affinity columns coupled with CAPRIN-1 protein or partial peptides, or the like. Furthermore, monoclonal antibodies can be obtained from non-human animals by collecting immune cells from the immunized animal and fusing them with myeloma cells. The fusion of the immune cells with myeloma cells can be carried out according to known methods (see Kohler, G. and Milstein, C. Methods Enzymol. (1981) 73, 3-46).

[0046] The antibodies used in the present invention can also be obtained as recombinant antibodies produced by cloning an antibody gene from a hybridoma, incorporating it into a suitable vector, and introducing it into a host using genetic engineering techniques (see Carl, A.K., Borrebaeck, James, W. Larrick, THERAPEUTIC MONOCLONAL ANTIBODIES, Published in the United Kingdom by MACMILLAN PUBLISHERS LTD, 1990).

[0047] The anti-CAPRIN-1 antibody used to obtain the conjugate of the present invention may have amino acids in the variable region (e.g., FR) or constant region substituted with other amino acids. The amino acid substitutions are one or more, for example, fewer than 15, fewer than 10, 8 or fewer, 6 or fewer, 5 or fewer, 4 or fewer, 3 or fewer, or 2 or fewer amino acids, preferably 1 to 9 amino acids. The substituted antibody should have the same or higher antigen-specific binding properties and antigen-binding affinity as the unsubstituted antibody, and should not cause rejection reactions when administered to humans.

[0048] The anti-CAPRIN-1 antibody used in the present invention is expected to have a stronger antitumor effect if it has a higher binding affinity with the CAPRIN-1 protein on the surface of cancer cells. ７ M －１ , at least 10 ８ M －１ , at least 5 × 10 ８ M －１ , at least 10 ９ M －１ , at least 5 × 10 ９ M －１ , at least 10 １０ M －１ , at least 5 × 10 １０ M －１ , at least 10 １１ M －１ , at least 5 × 10 １１ M －１ , at least 10 １２ M －１, or at least 10 １３ M －１ It is desirable that:

[0049] The binding ability of the anti-CAPRIN-1 antibody used in the present invention to effector cells can be improved by substituting one, two, or several amino acids in the heavy chain constant region of the antibody, or by removing fucose bound to N-acetylglucosamine in the N-glycoside-linked sugar chain bound to the heavy chain constant region. The above may be achieved by amino acid substitution alone, or may be a composition with an antibody bound to fucose.

[0050] Antibodies in which one, two, or several amino acids in the heavy chain constant region have been substituted can be produced by referring to, for example, WO2004 / 063351, WO2011 / 120135, U.S. Patent No. 8,388,955, WO2011 / 005481, U.S. Patent No. 6,737,056, and WO2005 / 063351.

[0051] An antibody from which fucose bound to N-acetylglucosamine in the N-glycoside-linked sugar chain in the heavy chain constant region has been removed, or a cell producing such an antibody, can be prepared with reference to U.S. Patent No. 6,602,684, European Patent No. 1,914,244, and U.S. Patent No. 7,579,170. An antibody from which fucose bound to N-acetylglucosamine in the N-glycoside-linked sugar chain bound to the heavy chain constant region has been removed, or a composition of an antibody to which fucose has been bound, or a cell producing such an antibody, can be prepared with reference to, for example, U.S. Patent No. 8,642,292.

[0052] The anti-CAPRIN-1 polyclonal antibody, anti-CAPRIN-1 monoclonal antibody, antibody production method, purification method, and method for producing the CAPRIN-1 protein or its partial polypeptide used in immunization used in the present invention are described in WO2010 / 016526, WO2011 / 096517, WO2011 / 096528, WO2011 / 096519, WO2011 / 096533, WO2011 / 096534, and WO2011 / 09653 5, WO2013 / 018886, WO2013 / 018894, WO2013 / 018892, WO2013 / 018891, WO2013 / 018889, WO2013 / 018883, WO2013 / 125636, WO2013 / 125654, WO2013 / 125630, WO2013 / 125640, WO2013 / 147169, WO2013 / 147176 and WO2015 / 020212.

[0053] Specific examples of the anti-CAPRIN-1 antibody of the present invention include those described in WO2010 / 016526, WO2011 / 096517, WO2011 / 096528, WO2011 / 096519, WO2011 / 096533, WO2011 / 096534, WO2011 / 096535, WO2013 / 018886, WO2013 / 018894, WO2013 / 018892, and WO2013 / 01889 1, WO2013 / 018889, WO2013 / 018883, WO2013 / 125636, WO2013 / 125654, WO2013 / 125630, WO2013 / 125640, WO2013 / 147169, WO2013 / 147176, and WO2015 / 020212, but preferred anti-CAPRIN-1 antibodies include the following:

[0054] An antibody or fragment thereof that is immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having an amino acid sequence represented by SEQ ID NO: 2 or SEQ ID NO: 4, or an amino acid sequence that has 80% or more (preferably 85% or more, more preferably 90% or more, even more preferably 95% or more, and still more preferably 99% or more) sequence identity with said amino acid sequence.

[0055] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence represented by SEQ ID NO: 31 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. An antibody or fragment thereof immunologically reactive with a CAPRIN-1 protein, preferably comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 36, 37, and 38 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 40, 41, and 42 (CDR1, CDR2, and CDR3, respectively), or an antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 140, 141, and 142 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 143, 144, and 145. or an antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 164, 165, and 166 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 167, 168, and 169 (CDR1, CDR2, and CDR3, respectively), and having immunological reactivity with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof has a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 39 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 43, or a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 70 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 71, or a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 78 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 79.

[0056] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 33 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 60, 61, and 62 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 64, 65, and 66 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 63 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 67.

[0057] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 32 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 52, 53, and 54 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 56, 57, and 58 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 55 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 59.

[0058] An antibody or fragment thereof that is immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence represented by SEQ ID NO: 34 or an amino acid sequence that has 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 170, 171, and 172 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 173, 174, and 175 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with the CAPRIN-1 protein; or an antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 176, 177, and 178 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 179, 180, and 181 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with the CAPRIN-1 protein. More preferably, the antibody or fragment thereof has a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 80 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 81, or an antibody or fragment thereof has a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 82 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 83.

[0059] An antibody or fragment thereof that is immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 35 or an amino acid sequence that has 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 182, 183, and 184 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 185, 186, and 187 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with the CAPRIN-1 protein; or an antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity determining regions of SEQ ID NOs: 188, 189, and 190 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity determining regions of SEQ ID NOs: 191, 192, and 193 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with the CAPRIN-1 protein. More preferably, the antibody or fragment thereof has a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 84 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 85, or an antibody or fragment thereof has a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 86 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 87.

[0060] An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 44, 45, and 46, and a light chain variable region comprising the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 48, 49, and 50, and having immunological reactivity with a CAPRIN-1 protein. Preferably, the antibody or fragment thereof comprises the heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 47, and the light chain variable region comprising the amino acid sequence of SEQ ID NO: 51.

[0061] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 296 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 146, 147, and 148 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 149, 150, and 151 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 72 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 73.

[0062] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 297 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 272, 273, and 274 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 275, 276, and 277 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 114 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 115.

[0063] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 298 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 290, 291, and 292 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 293, 294, and 295 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 120 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 121.

[0064] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 299 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 301, 302, and 303 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 305, 306, and 307 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 300 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 304.

[0065] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 308 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 134, 135, and 136 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 137, 138, and 139 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 68 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 69.

[0066] An antibody or fragment thereof immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having the amino acid sequence set forth in SEQ ID NO: 309 or an amino acid sequence having 80% or more (preferably 85% or more, more preferably 90% or more, and even more preferably 95% or more) sequence identity with said amino acid sequence. Preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 134, 135, and 136 (CDR1, CDR2, and CDR3, respectively) and a light chain variable region comprising the complementarity-determining regions of SEQ ID NOs: 137, 138, and 139 (CDR1, CDR2, and CDR3, respectively), and is immunologically reactive with a CAPRIN-1 protein. More preferably, the antibody or fragment thereof comprises a heavy chain variable region comprising the amino acid sequence of SEQ ID NO: 68 and a light chain variable region comprising the amino acid sequence of SEQ ID NO: 69.

[0067] In addition, the following anti-CAPRIN-1 antibodies are also preferably used.

[0068] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 68 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 69.

[0069] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 70 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 71.

[0070] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 72 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 73.

[0071] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 74 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 75.

[0072] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 76 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 77.

[0073] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 78 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 79.

[0074] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 80 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 81.

[0075] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 82 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 83.

[0076] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 84 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 85.

[0077] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 86 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 87.

[0078] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 88 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 89.

[0079] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 90 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 91.

[0080] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 92 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 93.

[0081] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 94 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 95.

[0082] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 96 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 97.

[0083] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO:98 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:99.

[0084] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 100 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 101.

[0085] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 102 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 103.

[0086] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 104 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 105.

[0087] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 106 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 107.

[0088] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 108 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 109.

[0089] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 110 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 111.

[0090] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 112 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 113.

[0091] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 114 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 115.

[0092] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 116 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 117.

[0093] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 118 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 119.

[0094] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 120 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 121.

[0095] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 122 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 123.

[0096] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 124 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 125.

[0097] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 126 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 127.

[0098] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 128 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 129.

[0099] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 130 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 131.

[0100] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 132 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 133.

[0101] An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 300 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 304.

[0102] In the Examples described below, conjugates of microtubule-regulating agents were prepared using the above-mentioned polyclonal and monoclonal antibodies against the full-length CAPRIN-1 protein and a portion of the polypeptide region expressed on the cell membrane surface of cancer cells, and their strong antitumor effects were confirmed.

[0103] <Dolastatin 10 or Derivative Thereof> The dolastatin 10 or derivative thereof used in the present invention is not particularly limited as long as it is a compound that acts directly on microtubules to inhibit microtubule formation or mitosis, but is preferably a compound that inhibits microtubule polymerization (microtubule destabilizers) shown below and has antitumor activity.

[0104] Dolastatin 10 is a compound extracted from Dolabella auricularia, a mollusk belonging to the family Aplysia of the order Opisthobranchia, and is a pentapeptide compound formed by linking the amino acids dolavalin (Dov), valine (Val), dolaisoleucine (Dil), dolaproline (Dap), and dolafenin (Doe). The dolavalin moiety on the N-terminal side of dolastatin 10 is N,N-dimethylvaline.

[0105] Dolastatin 10 derivatives are compounds in which some of the amino acids constituting dolastatin 10 have been substituted or deleted, or compounds in which other amino acids have been added to the pentapeptide, or compounds in which the pentapeptide has been modified with a substituent. Specific examples include peptide compounds in which valine (Val), dolaisoline (Dil), dolaproine (Dap), and dolafenine (Doe) are linked together, peptide compounds in which dolaisoline (Dil), dolaproine (Dap), and dolafenine (Doe) are linked together, and compounds in which the pyrrolidine ring of the dolaproine (Dap) portion of dolastatin 10 has been modified (e.g., CT-P26), and like dolastatin 10, they have antitumor activity.

[0106] The dolastatin 10 derivatives used in the present invention include those described in "Pettit G. R. et al., Antineoplastic agents 337. Synthesis of dolastatin 10 structural modifications. 1995 Oct; 10(7): 529-44" and "Pettit G. R. et al., Antineoplastic agents 337. Synthesis of dolastatin 10 structural modifications. 1995 Oct; 10(7): 529-44" al. Med. Chem. ", U.S. Patent 4,486,414, U.S. Patent 4,816,444, U.S. Patent 4,986,988, U.S. Patent 4,978,744, U.S. Patent ... ,780,588, U.S. Patent 5,530,097, U.S. Patent 5,665,860, U.S. Patent 5,635,483, U.S. Patent 5,559,902, U.S. Patent 5,530,097, U.S. Patent 6,239,104, U.S. Patent 6,034,065, WO1994 / 013695, WO1993 / 023424, JP-A-9-77791, U.S. Patent 4,879,298, WO93 / 03054, WO95 / 09864, WO 96 / 33212, U.S. Patent 5,840,699, WO2017 / 170637, WO2002 / 088172, U.S. Patent 6,884,869, U.S. Patent 7,098,308, U.S. Patent 7,256,257, U.S. Patent 7,423,116, WO2004 / 010957, U.S. Patent 7,659,241, U.S. Patent 7,659,241, U.S. Patent 7,851,437, U.S. Patent 8,906,376, WO2011 / 154359, U.S. Patent 8,722,629, WO2012 / 123423, U.S. Patent 9,029,406, European Patent 2686336, WO2005 / 081711, WO2006 / 132670, WO2007 / 008603, WO2012 / 123423, U.S. Patent 9,029,406, WO2012 / 143495, WO2012 / 143496, WO2012 / 143497, U.S. Patent 8,992,932, Patent 06250735, Patent 06088488, WO2019 / 164987 (Patent Publication No. 2021-513990), WO2005 / 081711, WO2007 / 008603, WO2011 / 1154359, WO2014 / 046441, WO1993 / 023424, WO1994 / 0136 84, WO1996 / 040751, WO1996 / 040752, WO1997 / 005162, WO1997 / 017364, WO1998 / 042 78, WO1998 / 004581, WO1998 / 036765, WO1998 / 040400, WO1998 / 040092, WO1999 / 003 879, WO1999 / 015130, WO2000 / 002906, WO2001 / 018032, WO2003 / 08378, WO2006 / 063 707, WO2012 / 148943, WO2012 / 166559, WO2012 / 166560, WO2014 / 046441, WO2014 / 17 4060, WO2014 / 174062, WO2014 / 174064, WO2016 / 192527, WO2021 / 084532, WO2021 / 183542, CN109796522, CN110078787, US17 / 142169, and compounds described in WO2003 / 008378.

[0107] Dolastatin 10 derivatives preferably used in the present invention include a compound in which the thiazolephenethylamine at the C-terminal portion of dolastatin 10 is replaced with norephedrine (also called monomethyl auristain E or MMAE), a compound in which the thiazolephenethylamine at the C-terminal portion of dolastatin 10 is replaced with phenylalanine (also called monomethyl auristain F or MMAF) and its derivatives, a compound in which the C-terminal portion of dolastatin 10 is phenylmethylamine (auristatin PE (also called YHI-501 Sobidotin)), a compound in which the C-terminal portion of dolastatin 10 has an amino group, a hydroxy group, a carboxylic acid, or a hydroxylamine at the C-terminal portion of dolastatin 10, and others, such as PF-06380101, Tasidotin (also called Synthadotin), auristatin PHE, and auristatin PYE, amberstatin-269 (also known as Linked), N-demethyl-N-[4-(maleimidohexanohydrozide)-4-OxObutyl]auristatin W amide, BAY1168650 (also known as auristatin W derivative), auristatin 0101, auristatin 2-AQ, auristatin 6-AQ, Aur0101, monomethyl auristatin F-hydroxypropylamide (MMAF-HPA), auristatin EB (AEB), auristatin Examples of the antibacterial agent include EFP (AEFP), 5-benzoylvaleric acid-AE ester (AEVB), TZT-1027, sobridotin, CT-P26, and derivatives thereof, and preferred are monomethyl auristain E (MMAE), monomethyl auristain F (MMAF), and derivatives thereof.

[0108] Furthermore, dolastatin 10 derivatives preferably used in the present invention are compounds having a functional group at the C-terminus of dolastatin 10 described in WO2017 / 170637, and preferably the compounds shown in Tables 1 to 4. Specific examples include compounds having an ethyl ester, which are obtained by a predetermined method using a dolastatin 10 derivative having a carboxyl group at the 4-thiazole position as an intermediate, compounds having an ethyl amide, compounds having an ethyl ester, compounds having a carbon chain-type adipic acid, compounds having succinic acid, compounds having PEG, and compounds having iminodiacetic acid. More specifically, 2-((S)-1-(((2S,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-(2-mercaptoethyl)thiazolinone 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxylic acid 2-(tritylthio)ethyl, 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxylate 2-mercaptoethyl, 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-methyl-N-(2-(tritylthio)ethyl)thiazole-4-carboxamide, 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl )-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-(2-mercaptoethyl)-N-methylthiazole-4-carboxamide, 2-((S)-1-(((2S,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxylic acid 2-((tert-butoxycarbonyl)amino)ethyl, 2-((S)-1-(((2S,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxylic acid 2-aminoethyl, (2-(2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-methylthiazole-4-carboxamido)ethyl)carbamate tert-butyl, N-(2-aminoethyl)-2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-methylthiazole-4-carboxamide dihydrochloride, (2-(2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-methylthiazole-4-carboxamido)ethyl)(methyl)carbamic acid tert-Butyl, 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-methyl-N-(2-(methylamino)ethyl)thiazole-4-carboxamide dihydrochloride, 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-(2-hydroxyethyl)thiazo 2-((tetrahydro-2H-pyran-2-yl)oxy)ethyl 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamide)-N,3-dimethylbutanamide)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamide)-2-phenylethyl)thiazole-4-carboxylate, 2-((tetrahydro-2H-pyran-2-yl)oxy)ethyl 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamide)-N,2-Hydroxyethyl 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-(2-hydroxyethyl)-N-methylthiazole-4-carboxylate thiazole-4-carboxamide, N-(4-aminophenethyl)-2-((S)-1-(((2S,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxamide, tert-butyl (2-(2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxamido)ethyl)carbamate , N-(2-aminoethyl)-2-((S)-1-(((2S,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxamide dihydrochloride, (2-(2-((S)-1-(((2S,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxamido)ethyl)(methyl)carbamate tert-butyl, 2-((S)-1-(((2S,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-(2-(methylamino)ethyl)thiazole-4-carboxamide dihydrochloride, 2-((S)-1-(((2S,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-(2-(3-(tritylthio)propanamido)ethyl)thiazole-4-carboxamide, (2-((2-((tert-butoxycarbonyl)(methyl)amino)ethyl)disulfanayl)ethyl)(methyl)carbamic acid 4-(2-(2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylene (50-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-7-methyl-8,48-dioxo-11,14,17,20,23,26,29,32,35,38,41,44-dodecaoxa-3,4-dithia-7,47-diazapentacontyl)(methyl)carbamic acid 4-(2-(2-((S)-1-((2R,3R)-3-((S)-1-((3R,4R,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamide)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxamido)ethyl)phenyl, N2-(4-(((2-amino-4-oxo-4,8-dihydropteridin-6-yl)methyl)amino)benzoyl)-N5-((2S)-4-carboxy-1-((2-((1-(1-(4-(2-(2-((S)-1-((2R,3R)-3-((S)-1-((3R,4R,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)- 3-Methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxamido)ethyl)phenoxy)-2,9-dimethyl-1,10,50-trioxo-13,16,19,22,25,28,31,34,37,40,43,46-dodecaoxa-5,6-dithia-2,9,49-triazadopentacontan-52-yl)-2,5-diox N2-(4-(((2-amino-4-oxo-4,8-dihydropteridin-6-yl)methyl)amino)benzoyl)-N5-((2S)-4-carboxy-1-((2-((1-(1-(4-(2-(2-((S)-1-((2R,3R)-3-((S)-1- ((3R,4R,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)thiazole-4-carboxamido)ethyl)phenoxy)-2,9-dimethyl-1 ,10,50-trioxo-13,16,19,22,25,28,31,34,37,40,43,46-dodecaoxa-5,6-dithia-2,9,49-triazadopentacontan-52-yl)-2,5-dioxopyrrolidin-3-yl)thio)ethyl)amino)-1-oxobutan-2-yl)-L-glutamine, (2-((2-(2-((S)-1-((2R,3R)-3-((S)-1-((3R,4S,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-methylthiazole-4-carboxamido)ethyl)disulfaneyl)ethyl)(methyl)carbamic acid tert-butyl, 2-((S)-1-((2R,3R)-3-((S)-1-((3R,4R,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2-phenylethyl)-N-(50-(2,5-dioxo -2,5-dihydro-1H-pyrrol-1-yl)-7-methyl-8,48-dioxo-11,14,17,20,23,26,29,32,35,38,41,44-dodecaoxa-3,4-dithia-7,47-diazapentacontyl)-N-methylthiazole-4-carboxamide, N2-(4-(((2-amino-4-oxo-4,8-dihydropteridin-6-yl)methyl)amino)benzoyl -N5-((2S)-4-carboxy-1-((2-((1-(1-(2-((S)-1-((2R,3R)-3-((S)-1-((3R,4R,5S)-4-((S)-2-((S)-2-(dimethylamino)-3-methylbutanamido)-N,3-dimethylbutanamido)-3-methoxy-5-methylheptanoyl)pyrrolidin-2-yl)-3-methoxy-2-methylpropanamido)-2 -phenylethyl)thiazol-4-yl)-2,9-dimethyl-1,10,50-trioxo-13,16,19,22,25,28,31,34,37,40,43,46-dodecaoxa-5,6-dithia-2,9,49-triazadopentacontan-52-yl)-2,5-dioxopyrrolidin-3-yl)thio)ethyl)amino)-1-oxobutan-2-yl)-L-glutamine.

[0109] Furthermore, an example of the dolastatin 10 derivative preferably used in the present invention is demethyl dolastatin 10.

[0110] <Conjugate of anti-CAPRIN-1 antibody and dolastatin 10 or a derivative thereof> In the present invention, the bond between the anti-CAPRIN-1 antibody and dolastatin 10 or a derivative thereof in the conjugate of the anti-CAPRIN-1 antibody and dolastatin 10 or a derivative thereof is not particularly limited as long as it is a bond that can maintain anti-cancer activity, but a bond in which a linker structure is formed between the anti-CAPRIN-1 antibody and dolastatin 10 or a derivative thereof is preferred.

[0111] Here, the linker refers to a compound capable of binding an anti-CAPRIN-1 antibody to dolastatin 10 or a derivative thereof. Various known linkers may be used, or the activator structure may be appropriately chemically modified to allow direct binding.

[0112] The type of linker and the details of the binding method can be determined in accordance with known methods (see, for example, Greg T. Hermanson, Bioconjugate Techniques, Third Edition, WO2004 / 010957, WO2014 / 012479).

[0113] In embodiments of the invention, reactive groups attached to the anti-CAPRIN-1 antibody, dolastatin 10 or a derivative thereof, and the linker include the following:

[0114] Unless specifically chemically modified, reactive groups present in the amino acid sequence of an antibody or in glycoproteins modified with amino acids include primary amines (ε-amino), carboxyls, thiols (sulfhydryls), carbonyls (ketones or aldehydes), and hydroxyls. Primary amines are found at the N-terminus of polypeptides and in the side chains of lysine residues. They are positively charged under physiological conditions and are usually located on the outside of proteins, allowing them to be used for conjugation without altering the protein structure. Carboxyls are found at the C-terminus of polypeptides and in the side chains of aspartic acid and glutamic acid. Sulfhydryls are found in the side chains of cysteine ​​and form disulfide bonds that maintain the higher-order structure of proteins. Ketones or aldehydes are generated in glycoproteins by oxidizing glycosyl groups with sodium metaperiodate.

[0115] The conjugates of the present invention are prepared by binding dolastatin 10 or a derivative thereof to a linker bound to the reactive group on an antibody, by binding dolastatin 10 or a derivative thereof to a linker bound to dolastatin 10 or a derivative thereof, or by binding dolastatin 10 or a derivative thereof directly to an antibody.

[0116] Reactive groups attached to the linker and microtubule-modulating agent include the following:

[0117] Reactive groups that can react with amines include N-hydroxysuccinimide (NHS) esters, imidoesters, pentafluorophenyl esters, hydroxymethylphosphine, isothiocyanates, isocyanates, acyl azides, N-hydroxyl esters, sulfonyl chlorides, aldehydes, glyoxals, epoxides, oxiranes, carbonates, aryls, carbodiimides, and carboxylic acid anhydrides.

[0118] Carbodiimides, diazoalkanes, diazoacetyl compounds, carbonyldiimidazoles are reactive groups that can react with carboxyls and amines.

[0119] Reactive groups that can react with thiols include maleimide, haloacetamide, pyridyl disulfide, thiosulfone, vinyl sulfone, haloacetyl, aziridine, acryloyl, and aryl.

[0120] Reactive groups that can react with aldehydes include hydrazide and alkoxyamine, and reactive groups that can react with hydroxyl include epoxy, oxirane, carbonyldiimidazole, N,N'-disuccinimidyl carbonate, N-hydroxysuccinimidyl chloroformate, and isocyanate.

[0121] Isocyanate is a reactive group that can react to hydroxyl.

[0122] Photoreactive reactive groups include diazirine, aryl azide, aryl, benzophenol, and diazo compounds.

[0123] Specific examples of the linker having the reactive group include the following:

[0124] Examples of linkers having the same reactive group terminal include linkers having N-hydroxysuccinimide ester as the reactive group (e.g., Disuccinimidyl Glutarate (DSG), Disuccinimidyl Suberate (DSS), Bis(sulfosuccinimidyl)Suberate (BS3), Tris-(Succinimidyl)Aminotriacetate (TSAT), PEGylated Bis(Sulfosuccinimidyl)Suberate (BS(PEG))). ５ , BS(PEG) ９), Dithiobis (Succinimidyl Propionate) (DSP), 3,3'-dithiobis (sulfosuccinimidyl propionate) (DTSSP), ethylene glycol bis(succinimidyl succinate) (EGS), Sulfo-ethylene glycol bis(succinimidyl succinate (Sulfo-EGS), Dimethyl adipimidate・2HCl (DMA), Dimethyl pimelimidate・2HCl (DMP), Dimethyl suberimidate・2HCl (DMS), Dimethyl3,3'-dithiobispropionimidate・2H Cl (DTBP), 1,5-difluoro-2,4-dinitrobenzene (DFDNB), Disuccinimidyl tartrate (DST), Bis[2-(Succinimidooxycarbonyloxy)ethyl]Sulfone (BSOCOES), and linkers with maleimide as the reactive group (e.g., Bismaleimidoethane (BMOE), 1,4-bismaleimidobutane (BMB), Bismaleimidohexane (BMH), Tris(2-maleimidothyl)amine (TMEA), 1,8-bismaleimido-(PEG)). ２ (BM (PEG) ２ ), 1,8-bismaleimido-(PEG) ３ (BM (PEG) ３ ), Dithiobismaleimidoethane (DTME) is used.

[0125] The main linkers having different reactive group ends include linkers having NHS ester and maleimide reactive groups (e.g., AMAS, BMPS, GMBS, Sulfo-MBS, MBS, Sulfo-MBS, SMCC, Sulfo-SMCC, EMCS, Sulfo-EMCS, SMPB, Sulfo-SMPB, SMPH, LC-SMCC, Sulfo-KMUS, SM(PEG) ２ , SM(PEG) ４ , SM(PEG)６ , SM(PEG) ８ , SM(PEG) １２ , SM(PEG) ２４ ), linkers with NHS ester and pyridyldithiol as reactive groups (e.g., SPDP, LC-SPDP, Sulfo-LC-SPDP, SMPT, (PEG) ４ SPDP, PEG12-SPDP), linkers with NHS ester and haloacetyl as reactive groups (e.g., SIA, SBAP, SIAB, Sulfo-SIAB), linkers with NHS ester and aryl azide as reactive groups (e.g., ANB-NOS, Sulfo-SANPAH, ATFB), linkers with NHS ester and diazirine as reactive groups (e.g., SDA, Sulfo-SDA, LC-SDA, SDAD, Sulfo-SDAD), carbodiimide Linkers having a hydrazide as a reactive group (e.g., DCC, EDC, EDAC, NHS, Sulfo-NHS), linkers having a maleimide and a hydrazide as a reactive group (e.g., BMPH, EMCH, MPBH, KMUH), linkers having a pyridyldithiol and a hydrazide as a reactive group (e.g., PDPH), linkers having an isocyanate and a maleimide as a reactive group (e.g., PMPI), and linkers having an NHS ester and a psoralen as a reactive group (e.g., SPB) are used.

[0126] Other linkers include polypeptide-containing linkers, such as Fmoc-Ala-Ala-Asn-PAB, Fmoc-Ala-Ala-Asn(Trt)-PAB, and Fmoc-PEG. ３ -Ala-Ala-Asn(Trt)-PAB, Fmoc-PEG ４ -Ala-Ala-Asn(Trt)-PAB, Fmoc-Ala-Ala-Asn-PAB-PNP, Fmoc-Ala-Ala-Asn(Trt)-PAB-PNP, Fmoc-PEG ３ -Ala-Ala-Asn(Trt)-PAB-PNP, Azide-PEG ４ -Ala-Ala-Asn(Trt)-PAB-PNP, Mal-PEG ４-Ala-Ala-Asn(Trt)-PAB-PNP, Fmoc-Val-Cit-PAB-OH, Val-Cit-PAB-OH, Fmoc-Val-Cit-PAB-PNP, MC-Val-Cit-PAB, MC-Val-Cit-PAB-PNP, Phe-Lys(Trt)-PAB, Fmoc-Phe-Lys(Trt)-PAB-PNP, Fmoc-Gly3-Val-Cit-PAB, Fmoc-Gly3-Val-Cit-PAB-PNP, Ala-Ala-Asn-PAB TFA salt, etc. are used.

[0127] Also, Bis-PEG-acid, PEG Acid (e.g., Acid-PEG-TEMPO, Amino-PEG-acid, Amino-PEG-CH ２ CO ２ H, Aminoxy-PEG-acid, Azido-PEG-acid, Carboxy-PEG-sulfonic acid, Fmoc-N-amido-PEG-acid, Fmoc-N-amido-PEG-CH ２ CO ２ H, Fmoc-aminoxy-PEG-acid, Hydroxy-PEG-acid, Hydroxy-PEG-CH ２ CO ２ H, m-PEG-acid, m-PEG-(CH ２ ) ３ -acid, Methoxytrityl-N-PEG-acid, N-methyl-N-(t-Boc)-PEG-acid, Propargyl-PEG-acid, Propargyl-PEG-CH ２ CO ２ H, Propargyl-PEG-(CH ２ ) ３ -acid, t-Boc-N-amido-PEG-acid, t-Boc-N-amido-PEG-CH ２ CO ２H, t-Boc-Aminoxy-PEG-acid, Acid-PEG-PFP ester, Miscellaneous PEG acid, ), PEG PFP ester (e.g., Acid-PEG-PFP ester, Bis-PEG-PFP ester), Bis-PEG-NHS, PEG Aldehyde (e.g., m-PEG-aldehyde, m-PEG-benzaldehyde, Ald-PEG-acid, Ald-PEG-amine, Ald-PEG-azide, Ald-PEG-NH-Boc, Ald-PEG-NHS ester, Ald-PEG-TFP ester, Ald-PEG-t-butyl ester), PEG Tosylate (e.g., Azido-PEG-Tos, Hydroxy-PEG-Tos, m-PEG-Tos, t-Boc-Aminoxy-PEG-Tos, Trifluoroethyl-PEG-Tos, Tos-PEG-acid, Tos-PEG-CH ２ CO ２ H, Tos-PEG-alkyne, Tos-PEG-t-butyl ester, Tos-PEG-CH ２ CO ２ tBu, Tos-PEG-Tos, S-acetyl-PEG6-Tos, N-Tos-N-(t-butoxycarbonyl)-aminoxy-PEG ４ -Tos, Ms-PEG-Ms, Ms-PEG-t-butyl ester, PEG-Ms, Propargyl-PEG-Ms), Boc-PEG (e.g., Amino-PEG-t-Boc-Hydrazide, Azido-PEG-t-Boc-Hydrazide, Boc-NH-PEG-NH-Boc, Bromoacetamido-PEG-Boc-amine, m-PEG-ONHBoc, Mal-Alkyl-t-Boc-amine, N-Boc-PEG-alcohol, N-Boc-PEG-bromide, N-methyl-N-(t-Boc)-PEG-acid, t-Boc-N-amido-PEG-acid, t-Boc-N-amido-PEG-CH ２ CO ２H, t-Boc-N-Amido-PEG-amine, t-Boc-N-amido-PEG-azide, t-Boc-N-amido-PEG-NHS ester, t-Boc-N-amido-PEG-sulfonic acid), PEG NHS ester (e.g., Acid-PEG-NHS ester, Azido-PEG-NHS ester, Bis-PEG-NHS, Fmoc-PEG-NHS ester, m-PEG-NHS ester, m-PEG-NHS Carbonate, Mal-PEG-NHS ester, Propargyl-PEG-NHS ester, t-Boc-N-amido-PEG-NHS ester, t-Butoxycarbonyl-PEG-NHS ester), Fmoc-PEG (e.g., Fmoc-N-amido-PEG-acid, Fmoc-NH-PEG-CH ２ CO ２ H, Fmoc-PEG-NHS ester), Biotin PEG (e.g., Biotin PEG-acid, Biotin PEG-alcohol, Biotin PEG-alkyne, Biotin PEG-amine, Biotin PEG-azide, Biotin PEG-DBCO, Biotin PEG-hydrazide, Biotin-PEG-Mal, Biotin-PEG-NHS, Biotin-EDA-PEG-NHS, Biotin-PEG-oxyamine, Biotin-PEG-PFP, Biotin-EDA-PEG-PFP, Biotin-PEG-Tetrazine, Biotin-PEG-TFP, Azide-SS-biotin, Biotin-PEG ３ -SS-azide, DBCO-S-S-PEG ３ -Biotin, Dde Biotin-PEG4-Alkyne, Dde Biotin-PEG ４ -Azide, Dde Biotin-PEG ４ -DBCO, Diazo Biotin-PEG ３ -Alkyne, Diazo Biotin-PEG ３ -Azide, Diazo Biotin-PEG ３-DBCO、Diol Biotin-PEG ３ -Alkyne、Diol Biotin-PEG ３ -Azide、PC Biotin-PEG ３ -Alkyne、PC-Biotin-PEG ４ -PEG ４ -Alkyne、PC-Biotin-PEG ４ -PEG4-Alkyne、PC Biotin-PEG ３ -Azide、PC-Biotin-PEG4-PEG3-Azide、PC-Biotin-PEG ４ -NHS carbonate、PC DBCO-PEG ３ -Biotin、WSPC Biotin-PEG ３-DBCO, Fmoc-Lys (biotin-PEG)-OH, Fmoc-N-amido-(PEG-biotin)-acid, TAMRA-Azide-PEG-Biotin), PEG Phosphonate, Aminooxy PEG (e.g., Aminooxy-PEG-acid, Aminooxy-PEG-alcohol, Aminooxy-PEG-azide, Aminooxy-PEG-bromide, Aminooxy-PEG-methane, Aminooxy-PEG-Propargyl, Aminooxy-PEG-t-butyl ester, Aminooxy-PEG-Thiol, Bis-(Aminooxy)-PEG, t-Boc-Aminooxy-PEG-acid, t-Boc-Aminooxy-PEG-alcohol, t-Boc-Aminooxy-PEG-amine, t-Boc-Aminooxy-PEG-Azide, t-Boc-Aminooxy-PEG-Bromide, t-Boc-aminooxy-PEG-Methane, t-Boc-aminooxy-PEG-Propargyl, t-Boc-aminooxy-PEG-S-Ac, t-Boc-Aminooxy-PEG-Thiol, t-Boc-Aminooxy-PEG-Tos, Fmoc-aminooxy-PEG-acid, Trifluoroethyl-PEG-Aminooxy), Alkyne PEG (e.g., endo-BCN-PEG, exo-BCN-PEG, Propargyl-PEG-acid, Propargyl-PEG-CH ２ CO ２ H, Propargyl-PEG-(CH ２ ) ３ -acid, Propargyl-PEG-(CH ２ ) ３-methyl ester、Prropargyl-･Gmcrrylat e、Propargglll･･･alcohol、rrop argylmm･･mamine、.. G-methylamiine、| Propargylla. de、Propargyllm･･bromide、rro pargyl-･･omMaleimide、rropa gylmPEy-ｭs、Propargyllmm･om｢ｳester、PrropargylllEGsulffoiic I ester、Propargyl-･ym｣ｨ ２ 39 ２ tBu、Propargylll･･thiol、ｰcbd gummies carbonaate、 nooxy-EEorropargyl、 BismPropargyl-･1、mm PEGPropargyll) . ２ 39 ２ 2、2zido-EG(3H ２ ) ) ３ -methyl ester、｡zidomE･m｡crylatee｡ do-PEGalcoholl ２ ) ) ３ OH、｡zido-EGamine、｡zid o-PEmazide、｡zido-EMM I ylamine、｡zido-･mmethyll ester、｡zido-EE1mｮｳ esterr ２ 39 ２-NHS, Azido-PEG-oxazolidin-2-one, Azido-PEG-PFP ester, Azido-PEG-phosphonic acid, Azido-PEG-phosphonic acid ethyl ester, Azido-PEG-sulfonic acid, Azido-PEG-t-Boc-Hydrazide, Azido-PEG-t-butyl ester, Azido-PEG-CH ２ CO ２ -t-butyl ester, Azido-PEG-TFP ester, Azido-PEG-Tos, Aminooxy-PEG-azide, Bromo-PEG-azide, Bromoacetamido-PEG-azide, Carboxyrhodamine 110-PEG-Azide, Isothiocyanato-PEG-Azide, Isothiocyanato-PEG-Azide, m-PEG-azide, Propargyl-PEG-azide, TAMRA-PEG-Azide, t-Boc-N-Amino-PEG-Azide, t-Boc-Aminooxy-PEG-Azide, Thiol-PEG-Azide, Trifluoroethyl-PEG-Azide, Azido-PEG-amino acid, Azido-PEG ４ -4-nitrophenyl carbonate, S-Acetyl-PEG ３ -Azide, Azide, Trityl-PEG １０ -Azide), Alkyne PEG, DBCO-PEG, BCN-PEG, Propargyl-PEG, Bis-PEG-acid, Bis-PEG-NHS, Bis-PEG-PFP, Bis-Propargyl-PEG, Amine-PEG-Amine, Azido-PEG-azide, Bromo-PEG, Mal PEG are used.

[0128] Furthermore, Py-ds-Prp-Osu, Py-ds-dmBut-OSu, Py-ds-dmBut-OPFP, Py-ds-Prp-OPFP, MAL- HA-OSu, MAL-di-EG-OPFP, MAL-tri-EG-OPFP, MAL-tetra-EG-OPFP, N3-di-EG-OPFP, N3 -tri-EG-OPFP, N3-tetra-EG-OPFP, ALD-BZ-OSu, ALD-di-EG-OSu, ALD-tetra-EG-OSu, ALD-di-EG-OPFP, ALD-tetra-EG-OPFP, PHA-di-EG-OPFP, and PHA-tetra-EG-OPFP are used.

[0129] In another embodiment, polyethylene glycol (PEG) described in WO2015 / 057699 and WO2017 / 165851 can be used to obtain a conjugate that is expected to have better in vivo kinetics.

[0130] In another embodiment, the linker described in US Pat. No. 1,080,8039 or a polypeptide represented by -Gly-Gly-Phe-Gly- can be used.

[0131] The linker mediated between the anti-CAPRIN-1 antibody and dolastatin 10 or a derivative thereof may be composed of a single type or multiple types.

[0132] Methods for preparing a conjugate of an anti-CAPRIN-1 antibody and dolastatin 10 or a derivative thereof include a method in which dolastatin 10 or a derivative thereof is linked to the antibody using the ε-amino group of a lysine side chain, and a method in which cysteine ​​residues forming disulfide bonds in the antibody are linked to the antibody using a thiol formed by reduction treatment.

[0133] When using the ε-amino group of a lysine residue of an antibody, for example, an active ester (e.g., N-hydroxysuccinimide ester) is reacted to form an amide bond. In this case, since there are many lysine residues in an antibody, the binding reaction proceeds nonspecifically. In this embodiment, for example, sc-vc-PAB-MMAE or Osu-Glu-vc-PAB-MMAE can be used.

[0134] When using a thiol that forms a disulfide bond present in the side chain of a cysteine ​​of an antibody, a method is used in which the disulfide bond on the antibody is converted to a thiol using a reducing agent such as mercaptoethanol, followed by reaction with a maleimide or α-haloamide. Furthermore, methods using, for example, sulfonephenyloxadiazole or 4-cyanoethynyloxy derivatives can be used to stabilize thiol-mediated bonds. These bonds are more stable for longer periods than bonds formed by the conjugation reaction of cysteine ​​to maleimide. Furthermore, since stability is improved when the imide ring formed by the thiol group attached to the maleimide is opened by hydrolysis to form an amide bond, a linker having an amino group near the imide group can also be used. Another method involves linking dolastatin 10 or a derivative thereof between two thiols formed by the cysteine ​​thiol of an antibody via a disulfide bond. For example, a cross-linked bond can be formed using a linker with two disulfide bond sites, which can be generated from an amide group with two sulfones at the β-position, or dibromomaleimide.

[0135] The conjugates of the present invention can be prepared, for example, using the THIOMAB™ technology or ThioBridge™, which are methods that allow a fixed number of thiol groups to be introduced into a specific portion of an antibody (see Nature Biotechnology 26, 925-932 (2008) or Biocojugate Chem., 25(6), 1124-1136 (2014)).

[0136] The conjugate of the present invention can be prepared, for example, by reducing an antibody with the reducing agent dithiothreitol (DTT) in a phosphate buffer solution to obtain an antibody having a thiol reactive group, and then forming a conjugate with dolastatin 10 or a derivative thereof. In addition to the method using a reducing agent, the conjugate can also be obtained by adding a thiol group to the primary amine of a lysine residue in the antibody by introducing Traut's reagent (2-Iminothiolane or N-Succinimidyl S-Acetylthioacetate (SATA)).

[0137] The amount of thiol added to the antibody can be quantified, for example, by mixing a sample solution containing 5,5'-Dithiobis(2-nitrobenzoic acid) (DTNB) and an SH group with phosphate buffer (pH 8.0) and distilled water, adding a DTNB solution dissolved in phosphate buffer, Good's buffer, or Tris buffer, incubating for a certain period of time, and then measuring the absorbance at 412 nm (see G. L. Ellman, Arch. Biochem. Biophys., 82, 70 (1959)).

[0138] The thiol groups added by cleaving disulfide bonds in the antibody through reduction treatment are preferably subjected to a treatment (capping) to prevent re-formation of disulfide bonds, such as with N-ethylmaleimide (NEM) or 2-iodoacetamide (IAA).

[0139] Forming a conjugate by binding dolastatin 10 or a derivative thereof to a thiol group added to an antibody can be achieved by known methods. Specifically, for example, linker reagents having a maleimide group or a bromoacetamide group can be used as linker reagents that specifically bind to the thiol group of a reduced antibody. For example, N-succinimidyl-4-(N-maleimidomethyl)-cyclohexane-1-carboxylate (SMCC) is used as a linker having a maleimide group. In this case, the presence of an amino group in dolastatin 10 or a derivative thereof allows the formation of an amide bond with the N-succinimide group of SMCC, thereby obtaining a conjugate.

[0140] In another embodiment, an amide bond is first formed using SMCC with the amino group present in the activator, and then a thiol group added to the antibody side is reacted with the maleimide group of SMCC to which dolastatin 10 or a derivative thereof is bound to obtain a conjugate.

[0141] In another embodiment, a conjugate of an antibody and dolastatin 10 or a derivative thereof can be formed by using two linkers. For example, a conjugate is prepared by forming an amide bond between a primary amino group present in a lysine residue on the antibody and the N-succinimide group of SATA (N-succinimidyl-S-acetylthioacetate), and then adding a thiol group to the antibody. Dolastatin 10 or a derivative thereof containing an amino group, or one to which an amino group has been added according to a standard method, is reacted with SMCC to form an amide bond with the N-succinimide group in SMCC, and a conjugate can be obtained by reacting the maleimide group in SMCC to which dolastatin 10 or a derivative thereof is bound with the thiol group in SATA to which an antibody is bound.

[0142] In another embodiment, conjugates of an antibody and dolastatin 10 or a derivative thereof can be prepared by, for example, using maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl (mc-Val-Cit-PAB) as a linker. mc-val-Cit-PAB (mc-vc-PAB) is a linker that can be cleaved by intracellular proteases (e.g., cathepsin B). A thiol group is added to an antibody dissolved in phosphate buffer using DTT or the like. On the other hand, benzyloxycarbonyl (PAB) in mc-Val-Cit-PAB is reacted with a dolastatin or dolastatin derivative having an amino group to prepare dolastatin 10 or a derivative thereof bound to mc-val-Cit-PAB, and this can then be reacted with the aforementioned thiol-added antibody to obtain a conjugate. For example, mc-val-Cit-PAB-MMAE is obtained by linking MMAE, a dolastatin derivative, to mc-val-Cit-PAB by a predetermined method, or Vedotin is linked to MMAE or mafadotin is linked to MMAF.

[0143] In yet another embodiment, SATA is attached to a primary amino group in a lysine residue of an antibody to add a thiol group, and succinimidyl 3-(2-pyridyldithio)propionate (SPDP) is reacted with dolastatin 10 or a derivative thereof having an amino group to form an amide bond with the N-succinimide group in SPDP.

[0144] The linker used in the present invention is cleavable under intracellular conditions, and a substance having antitumor activity comprising dolastatin 10 or a derivative thereof, or comprising dolastatin 10 or a derivative thereof and a portion of the linker, is released within the cell. For example, the linker is cleaved by intracellular peptidases or proteases. Preferred linkers are those cleaved by lysosomal or endosomal proteases, cathepsin B, cathepsin D, or plasmin. Examples include linkers comprising a polypeptide (Val-Cit, Phe-Leu, or Gly-Phe-Leu-Gly) that can be cleaved by cathepsin B. More specifically, linkers described in U.S. Patent No. 6,214,345 can be used.

[0145] Furthermore, in another embodiment, as a means for improving the stability, solubility, and metabolism of the conjugate of the present invention in blood and the binding affinity of dolastatin 10 or a derivative thereof to an anti-CAPRIN-1 antibody, for example, a linker having glucuronic acid (preferably β-D-glucuronide) described in WO 2007 / 0711968 can be used. Alternatively, means described in WO 2013 / 173337, WO 2015 / 095755, WO 2015 / 123679, and WO 2018 / 031690 can be used.

[0146] Furthermore, in another embodiment, dolastatin 10 or a dolastatin 10 derivative can be site-specifically bound to an anti-CAPRIN-1 antibody using, for example, the means described in WO2006 / 65533 and WO2018 / 160683.

[0147] In yet another embodiment, a conjugate of two or more drugs including dolastatin 10 or a dolastatin 10 derivative with an anti-CAPRIN-1 antibody can be obtained by the method described in WO 2018 / 112253. Preferably, one of the two or more drugs is MMAE or MMAF.

[0148] To obtain a composition containing a conjugate of the anti-CAPRIN-1 antibody of the present invention and dolastatin 10 or a derivative thereof, the composition can be subjected to, for example, gel filtration chromatography, and then the peak with a higher molecular weight than the antibody before linker binding can be isolated. To detect the mass of the conjugate while maintaining the intact bivalent antibody, for example, the method described in WO2013 / 049410 can be used.

[0149] The number of dolastatin 10 or a derivative thereof bound per antibody in the conjugate of the anti-CAPRIN-1 antibody of the present invention and dolastatin 10 or a derivative thereof can be quantified by known methods such as mass spectrometry, ELISA, electrophoresis, and chromatography such as HPLC.

[0150] <Anti-tumor effect of conjugate> The conjugate of the present invention between the anti-CAPRIN-1 antibody and dolastatin 10 or a derivative thereof has anti-tumor activity in vitro or in vivo. Anti-tumor activity means reduction, elimination, inhibition of growth, apoptosis, necrosis, or killing of target cancer cells. Therefore, the anti-tumor effect of the conjugate of the present invention can be determined by examining the anti-tumor activity against cancer.

[0151] The in vivo antitumor effect can be assessed by administering the conjugate to a cancer-bearing organism, measuring the size of the tumor after administration, and examining the size of the cancer over time. The antitumor effect of the present invention can also be assessed by examining the survival rate. It can also be assessed by examining the ability to produce cytokines or chemokines. The antitumor effect of the conjugate of the present invention can be further assessed by examining the prevention of cancer, metastasis, or recurrence.

[0152] The conjugate of the present invention is expected to have a stronger antitumor effect if it has a higher binding affinity with the CAPRIN-1 protein on the surface of cancer cells. ７ M －１ , at least 10 ８ M －１, at least 5 × 10 ８ M －１ , at least 10 ９ M －１ , at least 5 × 10 ９ M －１ , at least 10 １０ M －１ , at least 5 × 10 １０ M －１ , at least 10 １１ M －１ , at least 5 × 10 １１ M －１ , at least 10 １２ M －１ , or at least 10 １３ M －１ It is desirable that:

[0153] The ability of the conjugate of the present invention to bind to CAPRIN-1 can be determined using binding assays such as surface plasmon resonance (SPR), ELISA, Western blotting, immunofluorescence, and flow cytometry.

[0154] As described above, the conjugates of the present invention have an enhanced anti-tumor effect compared to an anti-CAPRIN-1 antibody alone, and the enhancement rate is preferably 30% or more, more preferably 40% or more, even more preferably 50% or more, even more preferably 55% or more, even more preferably 60% or more, even more preferably 65% ​​or more, and most preferably 70% or more. The enhancement rate of the anti-tumor effect of the conjugates of the present invention compared to an anti-CAPRIN-1 antibody alone can be calculated by administering an effective amount of each to tumor-bearing mice under the same conditions and comparing the tumor volumes on or after day 10 after the start of administration.

[0155] <Pharmaceutical Composition, Method for Treating and / or Preventing Cancer> The target of the pharmaceutical composition for treating and / or preventing cancer of the present invention is not particularly limited, as long as it is a cancer (cell) that expresses the CAPRIN-1 protein.

[0156] As used herein, the terms "tumor" and "cancer" refer to malignant neoplasms and are used interchangeably.

[0157] The cancers targeted by the present invention may be any cancers that express CAPRIN-1 protein on the cell membrane surface, including, but not limited to, breast cancer, renal cancer, pancreatic cancer, colon cancer, lung cancer, brain tumor, stomach cancer, uterine cancer, ovarian cancer, prostate cancer, bladder cancer, esophageal cancer, leukemia, lymphoma, liver cancer, gallbladder cancer, sarcoma, mast cell tumor, melanoma, adrenocortical carcinoma, Ewing's tumor, Hodgkin's lymphoma, mesothelioma, and multiple myeloma, as well as testicular cancer, thyroid cancer, head and neck cancer, urothelial carcinoma, renal cell carcinoma, colorectal cancer, gastroesophageal junction cancer, hepatocellular carcinoma, glioblastoma, primary central nervous system lymphoma, primary testicular lymphoma, biliary tract cancer, sarcoma, fibrosarcoma, basal cell carcinoma, Paget's disease, and skin cancer.

[0158] More specifically, the cancers include, for example, breast adenocarcinoma, hybrid breast adenocarcinoma, malignant mixed breast tumor, intraductal papillary adenocarcinoma, recurrent metastatic breast cancer, lung adenocarcinoma, non-small cell lung cancer (NSCLC), squamous non-small cell lung cancer, squamous cell carcinoma, small cell carcinoma, large cell carcinoma, neuroepithelial tissue tumors such as glioma, glioblastoma, neuroblastoma, ependymoma, neuronal tumor, embryonal neuroectodermal tumor, schwannoma, neurofibroma, meningioma, chronic lymphocytic leukemia, lymphoma, gastrointestinal lymphoma, digestive lymphoma, small to medium cell lymphoma, cecal cancer, ascending colon cancer, descending colon cancer, transverse colon cancer, sigmoid colon cancer, rectal cancer, ovarian epithelial cancer, germ cell tumor, stromal cell tumor, pancreatic ductal carcinoma, invasive pancreatic ductal carcinoma, and adenocarcinoma of the pancreas. Metastatic adenocarcinoma, acinar cell carcinoma, adenosquamous carcinoma, giant cell tumor, intraductal papillary mucinous neoplasm, mucinous cystadenocarcinoma, pancreatoblastoma, pancreatic head cell tumor, Frantz tumor, serous cystadenocarcinoma, solid papillary carcinoma, gastrinoma, glucagonoma, insulinoma, multiple endocrine neoplasia 1 (Wermer syndrome), nonfunctioning islet cell tumor, somatostatinoma, VIP-secreting tumor, cervical cancer, endometrial cancer, fibrosarcoma, bone and joint sarcoma, Ewing's sarcoma, Wilms' tumor, hepatoblastoma, soft tissue sarcoma, acute leukemia, chronic leukemia, spinal cord tumor, malignant soft tissue tumor, teratoma group tumor, head and neck cancer including hypopharyngeal cancer, oropharynx cancer, tongue cancer, nasopharyngeal cancer, oral cancer, lip cancer, paranasal sinus cancer, laryngeal cancer, recurrent brain tumor, etc. Furthermore, the present invention also includes, but is not limited to, renal pelvis and urinary tract cancer, bladder cancer, urethral cancer, testicular tumor, malignant pleural mesothelioma, malignant osteosarcoma, pediatric malignant solid tumors (rhabdomyosarcoma, neuroblastoma, hepatoblastoma, medulloblastoma, nephroblastoma, retinoblastoma, central nervous system germ cell tumor, Ewing's sarcoma family tumors), and the like.

[0159] Furthermore, preferred subjects (patients) are mammals, including, for example, primates, pet animals, livestock, sport animals, etc., with humans, dogs, and cats being particularly preferred.

[0160] When the conjugates used in the present invention are used as pharmaceutical compositions, they can be formulated by methods known to those skilled in the art. For example, they can be used parenterally in the form of a sterile solution or suspension injection in water or other pharmaceutically acceptable liquid. For example, they can be formulated by appropriately combining them with pharmacologically acceptable carriers or vehicles, specifically, sterilized water, physiological saline, vegetable oils, emulsifiers, suspending agents, surfactants, stabilizers, flavoring agents, excipients, binders, etc., and mixing them in a unit dosage form required for generally accepted pharmaceutical practice. The amount of active ingredient in these formulations is such that an appropriate dose within the indicated range can be obtained.

[0161] When the conjugate of the present invention is used as a pharmaceutical composition, it can be formulated in a lyophilized state containing any salts, surfactants, buffers, sugars, and cryoprotectants (including some sugars).

[0162] Sterile compositions for injection can be formulated according to standard pharmaceutical practice using a vehicle such as distilled water for injection. Examples of aqueous solutions for injection include physiological saline, isotonic solutions containing glucose or other adjuvants, such as D-sorbitol, D-mannose, D-mannitol, and sodium chloride. These solutions may be used in combination with appropriate solubilizers, such as alcohols, specifically ethanol, polyalcohols such as propylene glycol and polyethylene glycol, and nonionic surfactants such as Polysorbate 80™ and HCO-60. Examples of oily solutions include sesame oil and soybean oil, which may be used in combination with solubilizers such as benzyl benzoate and benzyl alcohol. These solutions may also be combined with buffers such as phosphate buffer and sodium acetate buffer, soothing agents such as procaine hydrochloride, stabilizers such as benzyl alcohol, phenol, and antioxidants. The prepared injection solutions are typically filled into appropriate ampoules. Examples of oily solutions include sesame oil and soybean oil, which may be used in combination with solubilizers such as benzyl benzoate and benzyl alcohol. The injection solution may also be formulated with a buffer such as a phosphate buffer or a sodium acetate buffer, a soothing agent such as procaine hydrochloride, a stabilizer such as benzyl alcohol or phenol, or an antioxidant. The prepared injection solution is usually filled into an appropriate ampule.

[0163] Administration may be oral or parenteral, preferably parenteral, and specific examples include injections, intranasal administrations, pulmonary administrations, transdermal administrations, etc. Examples of injections include intravenous injections, intramuscular injections, intraperitoneal injections, subcutaneous injections, intratumoral injections, etc., which can be used for systemic or local administration.

[0164] Furthermore, an appropriate administration method can be selected depending on the patient's age, body weight, sex, symptoms, etc. The dosage of a pharmaceutical composition containing an antibody or a polynucleotide encoding an antibody can be selected, for example, from the range of 0.0001 mg to 1000 mg per kg of body weight per administration, such as 0.5 mg, 1 mg, 2 mg, 3 mg, 5 mg, 10 mg, 20 mg, 50 mg, 75 mg, 100 mg, 200 mg, 500 mg, or 1000 mg per kg of body weight per administration. Alternatively, the dosage can be selected, for example, from the range of 0.001 to 100,000 mg / body per patient, although it is not necessarily limited to these values.

[0165] The dosage and administration method will vary depending on the patient's weight, age, sex, symptoms, etc., but can be appropriately selected by those skilled in the art.

[0166] By administering to a subject a pharmaceutical composition for treating and / or preventing cancer, which contains the conjugate of the present invention as an active ingredient, cancers expressing CAPRIN-1 on the cell membrane surface, preferably breast cancer, kidney cancer, pancreatic cancer, colon cancer, lung cancer, brain tumor, stomach cancer, uterine cancer, ovarian cancer, prostate cancer, bladder cancer, esophageal cancer, leukemia, lymphoma, liver cancer, gallbladder cancer, sarcoma, mast cell tumor, melanoma, adrenocortical carcinoma, Ewing's tumor, Hodgkin's lymphoma, mesothelioma, multiple myeloma, testicular cancer, thyroid cancer, head and neck cancer, urothelial carcinoma, renal cell carcinoma, colorectal cancer, gastroesophageal junction cancer, hepatocellular carcinoma, glioblastoma, primary central nervous system lymphoma, primary testicular lymphoma, biliary tract cancer, sarcoma, fibrosarcoma, basal cell carcinoma, Paget's disease, or skin cancer, can be treated and / or prevented.

[0167] Cancer can be treated and / or prevented by administering to a subject a pharmaceutical composition for treating and / or preventing cancer, which contains the conjugate of the present invention as an active ingredient, in combination with one or more antitumor agents, either together or separately. Antitumor agents that can be used in the present invention include alkylating agents, platinum complexes, topoisomerase inhibitors, antimetabolites, anticancer antibiotics, alkaloid antitumor agents, immune checkpoint inhibitors, antitumor agents that inhibit angiogenesis, and molecular targeted drugs, which are used in standard cancer treatments.

[0168] The present invention will be specifically described below based on examples, but the scope of the present invention is not limited to these specific examples.

[0169] Example 1: Anti-CAPRIN-1 Polyclonal Antibody The anti-CAPRIN-1 polyclonal antibody immunologically reactive with the CAPRIN-1 protein used in the conjugate of the present invention was prepared by mixing 1 mg of human CAPRIN-1 recombinant protein represented by SEQ ID NO: 2 and SEQ ID NO: 4, prepared according to Example 3 of WO 2010 / 016526, with an equal volume of incomplete Freund's adjuvant (IFA) solution. This mixture was subcutaneously administered to rabbits four times every two weeks. Blood was then collected to obtain antisera containing the polyclonal antibody. The obtained antisera was purified using a protein G carrier (GE Healthcare Biosciences) to obtain a polyclonal antibody against the CAPRIN-1 protein (anti-CAPRIN-1 polyclonal antibody #1). Additionally, serum from a rabbit not administered the antigen was purified using a protein G carrier in the same manner as above to serve as a rabbit control antibody.

[0170] The following polyclonal antibodies #2 to #6 against partial polypeptides of CAPRIN-1 were obtained in the same manner as in the preparation of the polyclonal antibodies against the CAPRIN-1 protein.

[0171] Anti-CAPRIN-1 polyclonal antibody #2 against a partial polypeptide represented by SEQ ID NO: 37 (SEQ ID NO: 31 herein) described in SEQ ID NO: CAPRIN-1 protein WO2011 / 096528, anti-CAPRIN-1 polyclonal antibody #3 against a partial polypeptide represented by SEQ ID NO: 5 (SEQ ID NO: 32 herein) described in WO2013 / 018894, anti-CAPRIN-1 polyclonal antibody #4 against a partial polypeptide represented by SEQ ID NO: 5 (SEQ ID NO: 33 herein) described in WO2013 / 125654, anti-CAPRIN-1 polyclonal antibody #5 against a partial polypeptide represented by SEQ ID NO: 37 (SEQ ID NO: 34 herein) described in WO2011 / 096533, anti-CAPRIN-1 polyclonal antibody #6 against a partial polypeptide represented by SEQ ID NO: 37 (SEQ ID NO: 35 herein) described in WO2011 / 096534.

[0172] Example 2 Anti-CAPRIN-1 Monoclonal Antibody The following anti-CAPRIN-1 monoclonal antibody was used in the conjugate of the present invention.

[0173] A monoclonal antibody against CAPRIN-1 described in WO2011 / 096528, wherein CDR1 to CDR3 of the heavy chain variable region consist of the amino acid sequences of SEQ ID NO: 36, SEQ ID NO: 37, and SEQ ID NO: 38, respectively, and CDR1 to CDR3 of the light chain variable region consist of the amino acid sequences of SEQ ID NO: 40, SEQ ID NO: 41, and SEQ ID NO: 42, respectively (for example, an antibody comprising the amino acid sequence of a heavy chain variable region represented by SEQ ID NO: 39, which includes CDR1 to CDR3 of the heavy chain variable region, and the amino acid sequence of a light chain variable region represented by SEQ ID NO: 43, which includes CDR1 to CDR3 of the light chain variable region).

[0174] A monoclonal antibody against CAPRIN-1 described in WO2015 / 020212, wherein CDR1 to CDR3 of a heavy chain variable region consist of the amino acid sequences of SEQ ID NOs: 44, 45, and 46, respectively, and CDR1 to CDR3 of a light chain variable region consist of the amino acid sequences of SEQ ID NOs: 48, 49, and 50, respectively (for example, an antibody comprising the amino acid sequence of a heavy chain variable region represented by SEQ ID NO: 47, which includes CDR1 to CDR3 of the heavy chain variable region, and the amino acid sequence of a light chain variable region represented by SEQ ID NO: 51, which includes CDR1 to CDR3 of the light chain variable region).

[0175] A monoclonal antibody against CAPRIN-1 described in WO2011 / 096519, wherein CDR1 to CDR3 of the heavy chain variable region consist of the amino acid sequences of SEQ ID NO: 52, SEQ ID NO: 53, and SEQ ID NO: 54, respectively, and CDR1 to CDR3 of the light chain variable region consist of the amino acid sequences of SEQ ID NO: 56, SEQ ID NO: 57, and SEQ ID NO: 58, respectively (for example, an antibody comprising the amino acid sequence of a heavy chain variable region represented by SEQ ID NO: 55, which includes CDR1 to CDR3 of the heavy chain variable region, and the amino acid sequence of a light chain variable region represented by SEQ ID NO: 59, which includes CDR1 to CDR3 of the light chain variable region).

[0176] A monoclonal antibody against CAPRIN-1 described in WO2013 / 125654, wherein CDR1 to CDR3 of the heavy chain variable region consist of the amino acid sequences of SEQ ID NOs: 60, 61, and 62, respectively, and CDR1 to CDR3 of the light chain variable region consist of the amino acid sequences of SEQ ID NOs: 64, 65, and 66, respectively (for example, an antibody comprising the amino acid sequence of a heavy chain variable region represented by SEQ ID NO: 63, which includes CDR1 to CDR3 of the heavy chain variable region, and the amino acid sequence of a light chain variable region represented by SEQ ID NO: 67, which includes CDR1 to CDR3 of the light chain variable region).

[0177] A monoclonal antibody against CAPRIN-1 described in WO2011 / 096517, comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 68 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 69.

[0178] Monoclonal antibodies against CAPRIN-1 described in WO2011 / 096528 include an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 70 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 71; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 72 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 73; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 74 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 75; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 76 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 77; and an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 78 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 79.

[0179] A monoclonal antibody against CAPRIN-1 described in WO2011 / 096533, comprising an antibody having a heavy chain variable region with an amino acid sequence represented by the amino acid sequence of SEQ ID NO: 80 and a light chain variable region with an amino acid sequence represented by the amino acid sequence of SEQ ID NO: 81; and an antibody having a heavy chain variable region with an amino acid sequence represented by the amino acid sequence of SEQ ID NO: 82 and a light chain variable region with an amino acid sequence represented by the amino acid sequence of SEQ ID NO: 83.

[0180] A monoclonal antibody against CAPRIN-1 described in WO2011 / 096534, comprising an antibody having an amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 84 and an amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 85; and an antibody having an amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 86 and an amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 87.

[0181] Monoclonal antibodies against CAPRIN-1 described in WO2010 / 016526, which comprise an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 88 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 89; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 90 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 91; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 92 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 93; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 94; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 96 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 97; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 98 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 99; and an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 100 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 101.

[0182] A monoclonal antibody against CAPRIN-1 described in WO2013 / 018894, comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 102 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 103; and an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 104 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 105.

[0183] A monoclonal antibody against CAPRIN-1 described in WO2013 / 018892, comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 106 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 107.

[0184] A monoclonal antibody against CAPRIN-1 described in WO2013 / 018891, comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 108 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 109.

[0185] A monoclonal antibody against CAPRIN-1 described in WO2013 / 018889, comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 110 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 111.

[0186] A monoclonal antibody against CAPRIN-1 described in WO2013 / 018883, comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 112 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 113.

[0187] A monoclonal antibody against CAPRIN-1 described in WO2013 / 125636, comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 114 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 115.

[0188] A monoclonal antibody against CAPRIN-1 described in WO2013 / 125654, comprising an antibody having an amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 116 and an amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 117; and an antibody having an amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 118 and an amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 119.

[0189] A monoclonal antibody against CAPRIN-1 described in WO2013 / 125630, comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 120 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 121.

[0190] an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 122 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 123; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 124 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 125; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 126 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 127; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 128 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 129; an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 130 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 131; and an antibody comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 132 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 133.

[0191] For the above-mentioned anti-CAPRIN-1 monoclonal antibodies, a nucleotide sequence was designed so that a heavy chain variable region in which CDR1 to CDR3 consist of the amino acid sequences of SEQ ID NOs: 36, 37, and 38, respectively, and in which the framework regions comprise a human antibody sequence, could be expressed, and inserted into a mammalian expression vector into which the heavy chain constant region of human IgG1 had been inserted. Similarly, a nucleotide sequence was designed so that a light chain variable region in which CDR1 to CDR3 consist of SEQ ID NOs: 40, 41, and 42, respectively, and in which the framework regions comprise a human antibody sequence, could be expressed, and inserted into a mammalian expression vector into which the light chain constant region of human IgG1 had been inserted. The above two recombinant expression vectors were introduced into mammalian cells according to a standard method to obtain a culture supernatant containing humanized monoclonal antibody #1 against CAPRIN-1 (humanized antibody #1), in which CDRs 1 to 3 of the heavy chain variable region consist of the amino acid sequences of SEQ ID NOs: 36, 37, and 38, respectively, and CDRs 1 to 3 of the light chain variable region consist of the amino acid sequences of SEQ ID NOs: 40, 41, and 42, respectively.

[0192] Similarly, a nucleotide sequence was designed to enable expression of a heavy chain variable region represented by SEQ ID NO: 47, in which CDRs 1 to 3 of the heavy chain variable region consist of the amino acid sequences of SEQ ID NO: 44, SEQ ID NO: 45, and SEQ ID NO: 46, respectively, and in which the framework regions comprise the sequence of a human antibody, and this was inserted into a mammalian expression vector into which the heavy chain constant region of human IgG1 had been inserted. Similarly, a base sequence was designed to enable expression of a heavy chain variable region represented by SEQ ID NO:51, in which CDR1 to 3 of the light chain variable region consist of the amino acid sequences of SEQ ID NO:48, SEQ ID NO:49, and SEQ ID NO:50, respectively, and the framework regions comprise the sequence of a human antibody. This base sequence was inserted into a mammalian expression vector into which the heavy chain constant region of human IgG1 had been inserted, and the two recombinant expression vectors were introduced into mammalian cells according to standard methods to obtain a culture supernatant containing humanized anti-CAPRIN-1 monoclonal antibody #2 (humanized antibody #2), in which CDR1 to 3 of the heavy chain variable region consist of the amino acid sequences of SEQ ID NO:44, SEQ ID NO:45, and SEQ ID NO:46, and CDR1 to 3 of the light chain variable region consist of the amino acid sequences of SEQ ID NO:48, SEQ ID NO:49, and SEQ ID NO:50, respectively.

[0193] Similarly, a culture supernatant containing humanized anti-CAPRIN-1 monoclonal antibody #3 (humanized antibody #3) was obtained, in which CDRs 1 to 3 of the heavy chain variable region consisted of the amino acid sequences of SEQ ID NOs: 52, 53, and 54, respectively, and CDRs 1 to 3 of the light chain variable region consisted of the amino acid sequences of SEQ ID NOs: 56, 57, and 58, respectively.

[0194] Similarly, a culture supernatant containing humanized anti-CAPRIN-1 monoclonal antibody #4 (humanized antibody #4) was obtained, in which CDRs 1 to 3 of the heavy chain variable region consisted of the amino acid sequences of SEQ ID NOs: 60, 61, and 62, respectively, and CDRs 1 to 3 of the light chain variable region consisted of the amino acid sequences of SEQ ID NOs: 64, 65, and 66, respectively.

[0195] Similarly, culture supernatants containing the following humanized anti-CAPRIN-1 monoclonal antibodies #9 to #41 (humanized antibodies #9 to #41) were obtained.

[0196] Humanized monoclonal antibody #9 (humanized antibody #9) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 68 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 69.

[0197] Humanized monoclonal antibody #10 (humanized antibody #10) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 70 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 71.

[0198] Humanized monoclonal antibody #11 (humanized antibody #11) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 72 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 73.

[0199] Humanized monoclonal antibody #12 (humanized antibody #12) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 74 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 75.

[0200] Humanized monoclonal antibody #13 (humanized antibody #13) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 76 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 77.

[0201] Humanized monoclonal antibody #14 (humanized antibody #14) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 78 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 79.

[0202] Humanized monoclonal antibody #15 (humanized antibody #15) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 80 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 81.

[0203] Humanized monoclonal antibody #16 (humanized antibody #16) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 82 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 83.

[0204] Humanized monoclonal antibody #17 (humanized antibody #17) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 84 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 85.

[0205] Humanized monoclonal antibody #18 (humanized antibody #18) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 86 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 87.

[0206] Humanized monoclonal antibody #19 (humanized antibody #19) comprising the amino acid sequence of the heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 88 and the amino acid sequence of the light chain variable region represented by the amino acid sequence of SEQ ID NO: 89.

[0207] Humanized monoclonal antibody #20 (humanized antibody #20) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 90 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 91.

[0208] Humanized monoclonal antibody #21 (humanized antibody #21) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 92 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 93.

[0209] Humanized monoclonal antibody #22 (humanized antibody #22) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 94 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 95.

[0210] Humanized monoclonal antibody #23 (humanized antibody #23) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 96 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 97.

[0211] Humanized monoclonal antibody #24 (humanized antibody #24) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 98 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 99.

[0212] Humanized monoclonal antibody #25 (humanized antibody #25) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 100 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 101.

[0213] Humanized monoclonal antibody #26 (humanized antibody #26) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 102 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 103.

[0214] Humanized monoclonal antibody #27 (humanized antibody #27) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 104 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 105.

[0215] Humanized monoclonal antibody #28 (humanized antibody #28) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 106 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 107.

[0216] Humanized monoclonal antibody #29 (humanized antibody #29) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 108 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 109.

[0217] Humanized monoclonal antibody #30 (humanized antibody #30) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 110 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 111.

[0218] Humanized monoclonal antibody #31 (humanized antibody #31) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 112 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 113.

[0219] Humanized monoclonal antibody #32 (humanized antibody #32) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 114 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 115.

[0220] Humanized monoclonal antibody #33 (humanized antibody #33) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 116 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 117.

[0221] Humanized monoclonal antibody #34 (humanized antibody #34) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 118 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 119.

[0222] Humanized monoclonal antibody #35 (humanized antibody #35) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 120 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 121.

[0223] Humanized monoclonal antibody #36 (humanized antibody #36) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 122 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 123.

[0224] Humanized monoclonal antibody #37 (humanized antibody #37) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 124 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 125.

[0225] Humanized monoclonal antibody #38 (humanized antibody #38) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 126 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 127.

[0226] Humanized monoclonal antibody #39 (humanized antibody #39) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 128 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 129.

[0227] Humanized monoclonal antibody #40 (humanized antibody #40) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 130 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 131.

[0228] Humanized monoclonal antibody #41 (humanized antibody #41) comprising the amino acid sequence of a heavy chain variable region represented by the amino acid sequence of SEQ ID NO: 132 and the amino acid sequence of a light chain variable region represented by the amino acid sequence of SEQ ID NO: 133.

[0229] Furthermore, for humanized antibody #1 of the above anti-CAPRIN-1 monoclonal antibodies, a nucleotide sequence was designed to enable expression of a heavy chain variable region in which CDRs 1 to 3 of the heavy chain variable region consist of the amino acid sequences of SEQ ID NOs: 36, 37, and 38, respectively, and in which the framework regions comprise the sequence of a human antibody, and this was inserted into a mammalian expression vector containing the heavy chain constant region of human IgG1 in which serine (Ser), amino acid 239 (EU numbering), has been substituted with aspartic acid (Asp) and isoleucine (Ile), amino acid 332 (EU numbering), has been substituted with glutamic acid (Glu). Furthermore, a nucleotide sequence was designed to enable expression of a light chain variable region in which CDRs 1 to 3 of the light chain variable region consist of SEQ ID NOs: 40, 41, and 42, respectively, and in which the framework regions comprise the amino acid sequence of a human antibody, and this was inserted into a mammalian expression vector containing the light chain constant region of human IgG1. The two recombinant expression vectors were introduced into mammalian cells according to standard methods to obtain a culture supernatant containing monoclonal antibody #5 against humanized CAPRIN-1 (humanized antibody #5), which consisted of the heavy chain full-length amino acid sequence consisting of the heavy chain variable region prepared above and a heavy chain constant region of human IgG1 in which serine (Ser), amino acid 239 (EU numbering), has been substituted with aspartic acid (Asp) and isoleucine (Ile), amino acid 332 (EU numbering), has been substituted with glutamic acid (Glu), and the light chain full-length amino acid sequence consisting of the light chain variable region and human light chain constant region prepared above.

[0230] Similarly, a culture supernatant containing humanized anti-CAPRIN-1 monoclonal antibody #6 (humanized antibody #6) consisting of the amino acid sequence of the heavy chain variable region and the amino acid sequence of the light chain variable region of the humanized antibody #2 prepared above was obtained.

[0231] Similarly, a culture supernatant containing humanized anti-CAPRIN-1 monoclonal antibody #7 (humanized antibody #7) consisting of the amino acid sequence of the heavy chain variable region and the amino acid sequence of the light chain variable region of the humanized antibody #3 prepared above was obtained.

[0232] Similarly, a culture supernatant containing humanized anti-CAPRIN-1 monoclonal antibody #8 (humanized antibody #8) consisting of the amino acid sequence of the heavy chain variable region and the amino acid sequence of the light chain variable region of the humanized antibody #4 prepared above was obtained.

[0233] Similarly, culture supernatants containing humanized anti-CAPRIN-1 antibodies #42 to #74 (humanized antibodies #42 to #74) each consisting of the amino acid sequence of the heavy chain variable region and the amino acid sequence of the light chain variable region of each of the humanized antibodies #9 to #41 prepared above were obtained.

[0234] The culture supernatants containing the obtained humanized anti-CAPRIN-1 monoclonal antibodies #1 to #74 were purified using Hitrap Protein A Sepharose FF (GE Healthcare) according to standard methods, and then substituted with PBS(-) and filtered through a 0.22 μm filter (Millipore) to prepare samples.

[0235] (Example 3) Preparation of conjugates of anti-CAPRIN-1 antibodies and a dolastatin 10 derivative (MMAE) 1 Conjugates of the anti-CAPRIN-1 polyclonal antibodies #1 to #6 described in Example 1 with MMAE were prepared using maleimidocaproyl-valine-citrulline-p-aminobenzyloxycarbonyl (mc-val-Cit-PAB) as a linker. These conjugates were prepared in accordance with the method described in WO2014 / 012479.

[0236] Anti-CAPRIN-1 polyclonal antibody #1 described in Example 1 was prepared in PBS(-) at a concentration of 10 mg / ml, and then a 0.45 mM TCEP-HCl solution dissolved in PBS(-) containing 2 mM EDTA was added so that the molar ratio of antibody to TCEP was 1:3, followed by a reduction reaction at 25°C for 2 hours. To the reduced solution, a dolastatin derivative mc-vc-PAB-MMAE (HY-15575, MCE) dissolved in DMSO at 5 mM was added so that the molar ratio of antibody to MMAE was 1:7.5, followed by a reaction at 25°C for 1 hour. After the reaction, the mixture was centrifuged at 15,000 rpm for 5 minutes, and the supernatant was collected and passed through a gel filtration column (40 kJ, ZEBA Spin desalting columns, Thermo) to remove unbound mc-vc-PAB-MMAE, followed by replacement with PBS(-). After removing unbound mc-vc-PAB-MMAE using the gel filtration column twice, the mixture was filtered through a 0.22 μm sterilizing membrane to obtain a solution containing the anti-CAPRIN-1 polyclonal antibody #1-mc-vc-PAB-MMAE (conjugate 1) of the present invention.

[0237] Similarly, solutions containing conjugates using mc-vc-PAB-MMAE were obtained for anti-CAPRIN-1 polyclonal antibodies #2 to #6 (the conjugate using anti-CAPRIN-1 polyclonal antibody #2: Conjugate 2, the conjugate using anti-CAPRIN-1 polyclonal antibody #3: Conjugate 3, the conjugate using anti-CAPRIN-1 polyclonal antibody #4: Conjugate 4, the conjugate using anti-CAPRIN-1 polyclonal antibody #5: Conjugate 5, and the conjugate using anti-CAPRIN-1 polyclonal antibody #6: Conjugate 6). Using the same procedure as above, a solution containing a conjugate of the rabbit control antibody and MMAE linker (control conjugate 1) was obtained in the same manner for the rabbit control antibody described in Example 1 that does not react with the CAPRIN-1 protein.

[0238] Furthermore, using a method similar to that described above, a solution containing a conjugate with MMAE (conjugate 7) was obtained using humanized antibody #1, which is the anti-CAPRIN-1 monoclonal antibody described in Example 2. Similarly, a solution containing a conjugate with MMAE (conjugate 8) was obtained using humanized antibody #2, one of the anti-CAPRIN-1 antibodies described in Example 2. In the same manner as described above, solutions containing a conjugate with MMAE (conjugate 9) were prepared using humanized antibody #3 described in Example 2, a conjugate with MMAE (conjugate 10) using humanized antibody #4, a conjugate with MMAE (conjugate 11) using humanized antibody #5, a conjugate with MMAE (conjugate 12) using humanized antibody #6, a conjugate with MMAE (conjugate 13) using humanized antibody #7, a conjugate with MMAE (conjugate 14) using humanized antibody #8, and conjugates with MMAE (conjugates 15 to 80) using humanized antibodies #9 to #74 were prepared, and the solutions were filtered through a 0.22 μm filter (Millipore).

[0239] Furthermore, as a comparative control, a dolastatin 15 derivative, which, like the dolastatin 10 derivative, acts directly on microtubules to inhibit microtubule formation or mitosis and is therefore toxic to cancer cells, was synthesized according to known information (Cancer Chemotherapy and Pharmacology. 2012, 70, 439-449), and a comparative conjugate of the antibody against CAPRIN-1 prepared in Examples 1 and 2 with the dolastatin 15 derivative was prepared according to the above method.

[0240] Example 4 Preparation of Conjugates of Anti-CAPRIN-1 Antibodies and Dolastatin 10 Derivative (MMAE) 2 Conjugates of the anti-CAPRIN-1 polyclonal antibodies #1 to #6 described in Example 1 and MMAE were prepared using OSu-Glu-vc-PAB-MMAE and OSu-vc-PAB-MMAE.

[0241] Anti-CAPRIN-1 polyclonal antibody #1 described in Example 1 was prepared in PBS(-) at a concentration of 5 mg / ml, and then OSu-Glu-vc-PAB-MMAE (SET0100, Levena Biopharma) or OSu-vc-PAB-MMAE (CS-0106796, ChemScene) was added so that the molar ratio of antibody to MMAE was 1:3-6. The reaction was then carried out at 20°C for 16 hours. After the reaction, unbound drug-linker was removed using a gel filtration column (NAP-10 column, Cytiva), and the solution was replaced with PBS(-). After removing unbound drug-linker using the gel filtration column twice, the solution was filtered using a 0.22 μm sterilizing filter membrane to obtain a solution containing the anti-CAPRIN-1 polyclonal antibody #1 (conjugate 81) of the present invention conjugated with MMAE.

[0242] Similarly, solutions containing conjugates using OSu-Glu-vc-PAB-MMAE or OSu-vc-PAB-MMAE were obtained for anti-CAPRIN-1 polyclonal antibodies #2 to #6 (the above conjugate using anti-CAPRIN-1 polyclonal antibody #2: Conjugate 82, the above conjugate using anti-CAPRIN-1 polyclonal antibody #3: Conjugate 83, the above conjugate using anti-CAPRIN-1 polyclonal antibody #4: Conjugate 84, the above conjugate using anti-CAPRIN-1 polyclonal antibody #5: Conjugate 85, and the above conjugate using anti-CAPRIN-1 polyclonal antibody #6: Conjugate 86). Using the same procedure as above, a solution containing a conjugate of the rabbit control antibody and MMAE linker (control conjugate 2) was obtained in the same manner for the rabbit control antibody described in Example 1 that does not react with the CAPRIN-1 protein.

[0243] Furthermore, using a method similar to that described above, a solution containing a conjugate with MMAE (conjugate 87) was obtained using humanized antibody #1, which is the anti-CAPRIN-1 monoclonal antibody described in Example 2. Similarly, a solution containing a conjugate with MMAE (conjugate 88) was obtained using humanized antibody #2, one of the anti-CAPRIN-1 antibodies described in Example 2. In the same manner as described above, solutions containing a conjugate with MMAE (conjugate 89) were obtained using humanized antibody #3 described in Example 2, a conjugate with MMAE (conjugate 90) using humanized antibody #4, a conjugate with MMAE (conjugate 91) using humanized antibody #5, a conjugate with MMAE (conjugate 92) using humanized antibody #6, a conjugate with MMAE (conjugate 93) using humanized antibody #7, a conjugate with MMAE (conjugate 94) using humanized antibody #8, and conjugates with MMAE (conjugates 95 to 160) using humanized antibodies #9 to #74. The solutions were then filtered through a 0.22 μm filter (Millipore).

[0244] (Example 5) Specific reactivity of conjugates with CAPRIN-1 protein and CAPRIN-1-expressing cancer cells Conjugates 1 to 80 prepared in Example 3 and conjugates 81 to 160 prepared in Example 4 were evaluated for their specific reactivity with CAPRIN-1 protein and their reactivity on the cell membrane surface of human cancer cells and mouse cancer cells expressing CAPRIN-1 protein.

[0245] Specific reactivity to the CAPRIN-1 protein was confirmed using ELISA. 100 μL of a 1 μg / mL CAPRIN-1 protein solution was added per well of a 96-well plate and incubated at 4°C for 18 hours. After washing each well three times with PBS-T, 400 μL of 0.5% bovine serum albumin (BSA) solution was added per well and incubated at room temperature for 3 hours. The solution was removed, and the wells were washed three times with 400 μL of PBS-T. Then, 100 μL of each solution containing conjugates 1-6, conjugates 81-86, and control conjugates 1 and 2 was added per well and incubated at room temperature for 2 hours. After washing each well three times with PBS-T, 100 μL of HRP-labeled anti-rabbit antibody diluted 5000-fold with PBS was added per well and incubated at room temperature for 1 hour. After washing the wells three times with PBS-T, 100 μL of TMB substrate solution was added per well and the plate was left to stand for 15 to 30 minutes to allow the color reaction to occur. After color development, 100 μL of 1 N sulfuric acid was added per well to stop the reaction, and the absorbance values ​​at 450 nm and 595 nm were measured using an absorption spectrometer. As a result, conjugates 1 to 6 and conjugates 81 to 86 had higher absorbance values ​​than the negative control conjugates 1 and 2, confirming that they react specifically with the CAPRIN-1 protein.

[0246] Similarly, specific reactions with the CAPRIN-1 protein were detected by ELISA using an HRP-labeled anti-human antibody for conjugates 7 to 80 and conjugates 87 to 160. As a result, the absorbance values ​​of conjugates 7 to 80 and conjugates 87 to 160 were higher than those of conjugates (control conjugates 3 and 4, respectively) conjugated to human IgG (SIGMA) used as a negative control in the same manner as in Examples 3 and 4, confirming that they specifically react with the CAPRIN-1 protein.

[0247] Next, the reactivity of CAPRIN-1-expressing cancer cells to the cell membrane surface was confirmed by flow cytometry. ５Human breast cancer cells BT-474 (obtained from ATCC) and mouse breast cancer cells 4T1 (obtained from ATCC) were centrifuged in 1.5 ml microcentrifuge tubes, and 100 μL of a solution containing conjugates 1 to 6, conjugates 81 to 86, and control conjugates 1 and 2 was added to each tube and allowed to stand at 4°C for 1 hour. After washing with PBS, Alexa488-labeled anti-rabbit IgG (H+L) diluted 100-fold with PBS(-) containing 0.5% FBS (0.5% FBS-PBS(-)) was added and allowed to stand at 4°C for 1 hour. After washing with 0.5% FBS-PBS(-), the cells were reacted with BD Horizon Fixable Viability Stain (FVS) Reagents (FVS450, Becton, Dickinson and Company) to stain dead cells, and then the fluorescence intensity was measured using a FACSFortessa™ (Becton, Dickinson and Company). As a result, it was confirmed that Conjugates 1 to 6 and Conjugates 81 to 86, which are conjugates of anti-CAPRIN-1 polyclonal antibody and MMAE, had higher fluorescence intensities than the negative control Conjugates 1 and 2, i.e., they strongly reacted with the cell surface of human cancer cell line BT474, which expresses CAPRIN-1.

[0248] Similarly, for conjugates 7 to 80 and conjugates 87 to 160, which are conjugates of an anti-CAPRIN-1 monoclonal antibody and MMAE, specific reactivity with CAPRIN-1-expressing cancer cells, human cancer cell BT474 and mouse cancer cell 4T1, was detected using an Alexa488-labeled anti-human IgG (H+L) antibody. As a result, it was confirmed that conjugates 7 to 80 and conjugates 87 to 160, which are conjugates of an anti-CAPRIN-1 polyclonal antibody and MMAE, had higher fluorescence intensity than the negative control conjugates 3 and 4, i.e., they strongly react with the cell surface of human cancer cell BT474, which expresses CAPRIN-1.

[0249] Similarly, the reactivity of conjugates 1 to 160 with various human cancer cells and mouse cancer cells was confirmed. These are human cancer cells in which expression of the CAPRIN-1 gene has been confirmed, including breast cancer cells (BT-474), colon cancer cells (HT-29), lung cancer cells (A549), gastric cancer cells (NCI-N87), uterine cancer cells (HEC-1-A), prostate cancer cells (22Rv1), pancreatic cancer cells (Panc10.5), liver cancer cells (Hep3B), ovarian cancer cells (SKOV3), and renal cancer cells (Cak The antitumor activity was evaluated against the following cancer cells: i-2), brain tumor cells (U-87MG), bladder cancer cells (T24), cholangiocarcinoma cells (KKU213), fibrosarcoma cells (HT-1080), esophageal cancer cells (OE33), leukemia cells (OCI-AML5), lymphoma cells (Ramos), gallbladder cancer cells (TGBC14TKB), melanoma cells (Malme-3M), mouse renal cancer cells (Renca), and mouse breast cancer cells (4T1) in which expression of the CAPRIN-1 gene has been confirmed. The results showed that conjugates 1 to 160, which are conjugates of an anti-CAPRIN-1 antibody and MMAE, had stronger fluorescence intensities than the negative control conjugates 1 to 4, and strongly reacted with the cell membrane surface of the above cancer cells in which CAPRIN-1 is expressed.

[0250] (Example 6) Antitumor Activity of Conjugates Conjugates 1 to 6 and conjugates 81 to 86, which were prepared using anti-CAPRIN-1 polyclonal antibodies #1 to #6 prepared in Examples 3 and 4, and conjugates 7 to 80 and conjugates 87 to 160, which were prepared using anti-CAPRIN-1 monoclonal antibodies, were evaluated in vitro for their antitumor activity against cancer cells. In Example 5, human cancer cells in which expression of CAPRIN-1 on the cell membrane surface of cancer cells has been confirmed were evaluated, including breast cancer cells (BT-474), colon cancer cells (HT-29), lung cancer cells (A549), gastric cancer cells (NCI-N87), uterine cancer cells (HEC-1-A), prostate cancer cells (22Rv1), pancreatic cancer cells (Panc10.5), liver cancer cells (Hep3B), ovarian cancer cells (SKOV3), renal cancer cells (Caki-2), and brain cancer cells (U- The antitumor activity was evaluated against mouse renal cell carcinoma (Renca) and mouse breast cancer (4T1) cells, which have been confirmed to express the CAPRIN-1 gene.

[0251] The cancer cells were cultured by a standard method and plated in a black 96-well plate suitable for cell culture (96 well optical Black Plate Polymer Base Black with Lid Cell Culture Sterile PS 165305, Thermo) at 1 to 4 x 10 cells per well. ４ The cells were seeded at 90 μL / well and incubated in 5% CO ２ The plates were cultured in an incubator at 37°C for 18 to 24 hours. Thereafter, 10 μL of each of conjugates 1 to 14 and conjugates 45 to 110 prepared in Example 3 and conjugates 15 to 28 and conjugates 111 to 176 prepared in Example 4 was added per well to a concentration of 0.001 μg / mL to 100 μg / mL, and the plates were incubated in a 5% CO ２The plates were incubated in an incubator at 37°C. Three to four days after the start of incubation, cell viability was measured using a Cell Titer Glow Luminescent Cell Viability Assay (#7573, Promega). 100 μL of substrate was added per well, and the plates were shaken for 2 minutes using a plate shaker. After allowing to stand for 10 minutes, the luminescence signal intensity was measured using a SpectraMax® iD3 (MOLECULAR DEVICE) to calculate the ATP content of surviving cells.

[0252] As a result, Conjugates 1 to 6 and Conjugates 81 to 86, which are conjugates of an antibody against CAPRIN-1 described in the present invention and MMAE, exhibited stronger antitumor activity than Control Conjugates 1 and 2, which were prepared using a control antibody that does not react with CAPRIN-1 protein. Furthermore, Conjugates 7 and 11, which are conjugates of an antibody against CAPRIN-1 described in the present invention and MMAE, showed that, for all cancer cells, 60% or less of the cancer cells survived, assuming the negative control (group without conjugate) to be 100%. Furthermore, Conjugates 8 to 80, Conjugates 12 to 80, and Conjugates 87 to 160 also showed results similar to those of Conjugates 7 and 11.

[0253] On the other hand, when the conjugate of the dolastatin 15 derivative prepared in Example 3 was used as a control group, the survival rate of cancer cells was 80% or more.

[0254] From the above results, it was revealed that the conjugate of an antibody against CAPRIN-1 and MMAE exhibits antitumor activity against cancer cells.

[0255] (Example 7) Antitumor Effect of Conjugates in Cancer-Bearing Mice The antitumor effect of the conjugates (conjugates 7 to 80, conjugates 87 to 160) of the antibody against CAPRIN-1 and MMAE prepared in Examples 3 and 4 was evaluated in vivo in cancer-bearing mice. The antitumor effect of the conjugate of the present invention was examined using NOD-SCID mice transplanted with human-derived cancer cells expressing CAPRIN-1 protein. 10 ７ Human colon cancer cells HT29 were mixed with Matrigel (SIGMA) and subcutaneously implanted, and the tumors grew to 50 mm ３ Tumor-bearing mice were prepared by growing the mice to a size of 100 or larger. HT29 expresses the CAPRIN-1 protein on the cell membrane surface, and as shown in Example 5, conjugates 1 to 6 and conjugates 81 to 86, which were prepared using anti-CAPRIN-1 polyclonal antibodies #1 to #6, and conjugates 7 to 80 and conjugates 87 to 160, which were prepared using anti-CAPRIN-1 monoclonal antibodies, specifically bind to the cell membrane surface. Each of the above conjugates was administered at 10 mg / kg into the tail vein of 10 tumor-bearing mice.

[0256] Furthermore, a solution containing a conjugate of trastuzumab (Chugai Pharmaceutical Co., Ltd.) and MMAE was prepared according to the method described in Example 3 so that the same level of drug binding was achieved as in the conjugate using an antibody against CAPRIN-1, and the same amount was administered to the above-mentioned tumor-bearing mice as a control. HT29 expresses HER2 protein, the target antigen of trastuzumab, on the cell membrane surface, to which the above-mentioned conjugate of trastuzumab and MMAE specifically binds. The tumor-bearing mice were administered twice a week.

[0257] PBS(-) was administered to tumor-bearing mice as a negative control.

[0258] After administration, the size of the tumor in the tumor-bearing mice was measured over time using a vernier caliper, and the tumor volume was calculated according to the standard method using the formula: (length of the longest axis of the tumor) x (length of the shortest axis of the tumor). ２× 0.5. As a result of the evaluation, on day 7 after the start of administration, when the tumor volume of the negative control was taken as 100%, the tumor volumes of the mice administered with conjugates 7 to 14 prepared in Example 3 and conjugates 87 to 94 prepared in Example 4 were all less than 30%. Thereafter, on day 25 after the start of administration, the tumors completely regressed. Similarly, the antitumor effects of conjugates 15 to 80 and conjugates 95 to 160 were evaluated in vivo in tumor-bearing mice, and the tumor volumes were all less than 30%. Furthermore, when the tumor volume of tumor-bearing mice administered only the antibody against CAPRIN-1 used in the above conjugates was taken as 100%, the tumor volumes of the tumor-bearing mice administered with the above conjugates were less than 32%.

[0259] On the other hand, the tumor volume of the mice administered with a solution containing the conjugate of trastuzumab and MMAE as a control was 65% or more of that of the negative control.Furthermore, when the tumor volume of the tumor-bearing mice administered with trastuzumab alone was taken as 100%, the tumor volume of the tumor-bearing mice administered with the conjugate was less than 81%.

[0260] As a result of this evaluation, it was shown that conjugates 7 to 80 and conjugates 87 to 160 prepared in Examples 3 and 4 using antibodies against CAPRIN-1 exhibited significantly stronger antitumor effects than the negative control (untreated control group). Furthermore, it was shown that conjugates 7 to 80 and conjugates 87 to 160 had significantly stronger antitumor effects than the conjugate of trastuzumab and MMAE prepared as a comparative control.

Claims

1. A conjugate comprising an antibody or a fragment thereof immunologically reactive with a CAPRIN-1 protein having an amino acid sequence represented by any of the even-numbered SEQ ID NOs: 2 to 30, or an amino acid sequence having 80% or more sequence identity with said amino acid sequence, and dolastatin 10 or a derivative thereof bound to the antibody or a fragment thereof.

2. The conjugate according to claim 1, wherein the antibody or a fragment thereof is immunologically reactive with a partial polypeptide of a CAPRIN-1 protein having an amino acid sequence represented by any one of SEQ ID NOs: 31 to 35, 296 to 299, 308, and 309, or an amino acid sequence having 80% or more sequence identity to said amino acid sequence.

3. The conjugate of claim 1 , wherein the antibody is a monoclonal antibody or a polyclonal antibody.

4. The conjugate according to claim 1, wherein the antibody or fragment thereof is any one of the following (A) to (M): (A) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 36, 37, and 38, respectively, and a light chain variable region comprising the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 40, 41, and 42, respectively, and having immunological reactivity with a CAPRIN-1 protein. (B) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 44, 45, and 46, respectively, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 48, 49, and 50, respectively, and having immunological reactivity with a CAPRIN-1 protein. (C) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 52, 53, and 54, respectively, and a light chain variable region comprising the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 56, 57, and 58, respectively, and having immunological reactivity with a CAPRIN-1 protein. (D) An antibody or fragment thereof comprising a heavy chain variable region comprising the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 60, 61, and 62, respectively, and a light chain variable region comprising the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 64, 65, and 66, respectively, and having immunological reactivity with a CAPRIN-1 protein. (E) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 170, 171, and 172, respectively, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 173, 174, and 175, respectively, and having immunological reactivity with a CAPRIN-1 protein. (F) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 176, 177, and 178, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 179, 180, and 181, respectively, and having immunological reactivity with a CAPRIN-1 protein. (G) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 182, 183 and 184, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 185, 186 and 187, respectively, and having immunological reactivity with CAPRIN-1 protein. (H) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 188, 189 and 190, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 191, 192 and 193, respectively, and having immunological reactivity with a CAPRIN-1 protein. (I) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 146, 147 and 148, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 149, 150 and 151, respectively, and having immunological reactivity with a CAPRIN-1 protein. (J) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 272, 273 and 274, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 275, 276 and 277, respectively, and having immunological reactivity with a CAPRIN-1 protein. (K) An antibody or fragment thereof having immunological reactivity with a CAPRIN-1 protein, comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 290, 291, and 292, respectively, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2, and CDR3) of SEQ ID NOs: 293, 294, and 295, respectively. (L) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3, respectively) of SEQ ID NOs: 300, 301 and 302 and a light chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3, respectively) of SEQ ID NOs: 304, 305 and 306, and having immunological reactivity with the CAPRIN-1 protein. (M) An antibody or fragment thereof comprising a heavy chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 134, 135 and 136, and a light chain variable region containing the complementarity determining regions (CDR1, CDR2 and CDR3) of SEQ ID NOs: 137, 138 and 139, and having immunological reactivity with a CAPRIN-1 protein.

5. The conjugate according to claim 4, wherein the antibody or fragment thereof is any one of the following (a) to (al): (a) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 39 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 43; (b) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 47 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 51; (c) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 55 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

59. (d) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 63 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

67. (e) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 68 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

69. (f) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 70 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

71. (g) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 72 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 73; (h) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 74 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

75. (i) An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 76 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

77. (j) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 78 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 79; (k) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 80 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

81. (l) An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 82 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

83. (m) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 84 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

85. (n) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 86 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 87; (O) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 88 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

89. (P) An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 90 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

91. (q) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 92 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 93; (r) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 94 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

95. (s) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 96 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

97. (T) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 98 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

99. (u) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 100 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

101. (v) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 102 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

103. (w) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 104 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

105. (x) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 106 and the light chain variable region comprises the amino acid sequence of SEQ ID NO: 107; (Y) An antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 108 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

109. (z) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 110 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

111. (aa) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 112 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

113. (ab) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 114 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

115. (ac) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 116 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

117. (ad) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 118 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

119. (ae) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 120 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

121. (af) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 122 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

123. (ag) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 124 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

125. (ah) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 126 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

127. (ai) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 128 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

129. (aj) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 130 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

131. (ak) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 132 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

133. (i) an antibody or fragment thereof, wherein the heavy chain variable region comprises the amino acid sequence of SEQ ID NO: 303 and the light chain variable region comprises the amino acid sequence of SEQ ID NO:

307.

6. The conjugate of claim 1 , wherein the antibody is a human antibody, a humanized antibody, a chimeric antibody, or a single-chain antibody.

7. The conjugate according to claim 1 , wherein the antibody or fragment thereof and dolastatin 10 or a derivative thereof are linked via a linker.

8. 2. The conjugate of claim 1, wherein the dolastatin 10 derivative is monomethyl auristatin E (MMAE), monomethyl auristatin F (MMAF), or a derivative thereof.

9. A pharmaceutical composition for treating and / or preventing cancer, comprising the conjugate according to any one of claims 1 to 8 as an active ingredient.

10. 10. The pharmaceutical composition of claim 9, further comprising one or more anti-tumor agents, in combination together or separately.

11. The pharmaceutical composition according to claim 9, wherein the cancer is a cancer that expresses CAPRIN-1 protein on the cell membrane surface.

12. The cancer is breast cancer, kidney cancer, pancreatic cancer, colon cancer, lung cancer, brain tumor, stomach cancer, uterine cancer, ovarian cancer, prostate cancer, bladder cancer, esophageal cancer, leukemia, lymphoma, liver cancer, gallbladder cancer, bile duct cancer, sarcoma, mast cell tumor, melanoma, adrenocortical carcinoma, Ewing's tumor, Hodgkin's lymphoma, mesothelioma, or multiple myeloma. The pharmaceutical composition according to claim 11, wherein the cancer is testicular cancer, thyroid cancer, head and neck cancer, urothelial carcinoma, renal cell carcinoma, colorectal cancer, gastroesophageal junction cancer, hepatocellular carcinoma, glioblastoma, primary central nervous system lymphoma, primary testicular lymphoma, biliary tract cancer, sarcoma, fibrosarcoma, basal cell carcinoma, Paget's disease, or skin cancer.