Antibody-drug conjugate

Abstract

An antibody-drug conjugate, having a structure as shown in the following formula 1, wherein Ab is an antibody or antibody fragment for targeting Lewis Y, and j is 1-8, preferably 4-8. The antibody-drug conjugate has a high specific binding ability to tumor cells expressing Lewis Y protein, thereby achieving an excellent killing effect on the cells.

Description

An antibody drug conjugate Technical Field

[0001] This application relates to the field of biomedical technology, and in particular to an antibody drug conjugate. Background Technology

[0002] Malignant tumors (cancer) have become the leading cause of death worldwide. The fundamental reasons for the high mortality rate of cancer are the spread and metastasis of cancer cells, and the high recurrence rate and drug resistance in most patients after treatment. Currently available clinical treatments, such as surgery, radiotherapy, and chemotherapy, have minimal or no effect on cancer cell metastasis, recurrence, or drug resistance, and cannot change the long-term survival of patients. Currently, surgical resection is effective for approximately 10-20% of early-stage patients, but almost ineffective for patients who have already experienced metastasis. Radiotherapy can only treat local lesions and is often used as adjuvant therapy before and after surgery, and as a radical treatment for a few types of cancer. Chemotherapy can be used for patients with metastasis, but due to its significant side effects and the tendency to develop short-term or long-term drug resistance, it only has a significant short-term effect on approximately 20-30% of patients. Even with comprehensive treatment combining surgery, radiotherapy, and chemotherapy, the 5-year survival rate has remained around 20-30% for many years, and approximately 70-80% of patients die within 5 years after treatment due to metastasis, recurrence, and drug resistance. Even some early-stage cancer patients who have no metastasis at the time of diagnosis still die from metastasis and recurrence after treatment. Summary of the Invention

[0003] Currently, identifying tumor-associated antigens and then delivering drugs to tumor cells in the form of antibody-drug conjugates is an effective method for treating tumors. This drug form combines the targeting specificity of monoclonal antibodies to tumor cells with the powerful tumor-killing advantages of small-molecule cytotoxic agents. It can significantly reduce the toxic side effects of small-molecule toxins while improving drug efficacy, thus exhibiting significant therapeutic advantages.

[0004] Lewis Y antigen is an oligosaccharide that binds to the ends of glycoproteins and glycolipids. It is a non-protein antigen widely present in various tumors, and its high expression level is closely related to tumor occurrence, development, and prognosis. Lewis Y antigen is highly expressed in multiple myeloma, acute myeloid leukemia, non-small cell lung cancer (NSCLC), small cell lung cancer, colorectal cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, esophageal cancer, and renal cancer. Due to its high expression level in various tumors and relatively low expression in normal tissues, Lewis Y antigen is considered a potential target for antibody-drug conjugates (ADCs).

[0005] Therefore, the applicant has developed an antibody-drug conjugate that binds to the Lewis Y antigen to achieve excellent cell-killing effects by targeting the Lewis Y antigen.

[0006] The technical solution of this application is as follows:

[0007] 1. An antibody-drug conjugate, comprising the structure of Formula 1:

[0008] Wherein, Ab is an antibody or antibody fragment used to target Lewis Y;

[0009] j can be 1 to 8, preferably 4 to 8.

[0010] 2. The antibody-drug conjugate according to item 1, wherein,

[0011] The antibody or antibody fragment for targeting Lewis Y comprises three heavy chain complementarity-determining regions (CDR-H1, CDR-H2, and CDR-H3) and three light chain complementarity-determining regions (CDR-L1, CDR-L2, and CDR-L3), wherein:

[0012] The amino acid sequence of CDR-H1 is shown in SEQ ID NO: 1 or 13;

[0013] The amino acid sequence of CDR-H2 is shown in SEQ ID NO: 2, 7, 10 or 14;

[0014] The amino acid sequence of CDR-H3 is shown in SEQ ID NO: 3, 8, 11 or 15;

[0015] The amino acid sequence of CDR-L1 is shown in SEQ ID NO: 4, 9, 12 or 16;

[0016] The amino acid sequence of CDR-L2 is shown in SEQ ID NO: 5 or 17;

[0017] The amino acid sequence of CDR-L3 is shown in SEQ ID NO: 6 or 18.

[0018] 3. The antibody-drug conjugate according to claim 1, wherein the antibody or antibody fragment for targeting LewisY comprises a heavy chain variable region and a light chain variable region, wherein,

[0019] The amino acid sequence of the heavy chain variable region is as shown in SEQ ID NO: 19, 21, 23 or 25, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 19, 21, 23 or 25.

[0020] The amino acid sequence of the light chain variable region is as shown in SEQ ID NO: 20, 22, 24 or 26, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 20, 22, 24 or 26.

[0021] 4. The antibody-drug conjugate according to any one of items 1-3, wherein the Ab is an antibody targeting Lewis Y, the heavy chain of the antibody is an IgG1 subtype or a mutated IgG1 subtype, and the light chain of the antibody is a Kappa type.

[0022] 5. The antibody-drug conjugate according to item 4, wherein the antibody for targeting Lewis Y comprises a heavy chain and a light chain, wherein,

[0023] The amino acid sequence of the heavy chain is as shown in SEQ ID NO: 27, 29, 31 or 33, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 27, 29, 31 or 33.

[0024] The amino acid sequence of the light chain is as shown in SEQ ID NO: 28, 30, 32 or 34, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 28, 30, 32 or 34.

[0025] 6. A method for preparing an antibody-drug conjugate, comprising the following steps:

[0026] LD-38 is available;

[0027] Construct antibodies or antibody fragments (Abs) for targeting Lewis Y;

[0028] LD-38 is conjugated with an antibody or antibody fragment Ab for targeting Lewis Y to obtain an antibody-drug conjugate.

[0029] The structure of LD-38 is as follows

[0030] The antibody or antibody fragment Ab used to target Lewis Y is described in references 1-5.

[0031] 7. A pharmaceutical composition comprising, wherein the antibody-drug conjugate described in any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof.

[0032] 8. Use of an antibody-drug conjugate comprising any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, in the preparation of a medicament for the treatment and / or prevention of tumors.

[0033] 9. The use according to item 8, wherein the tumor is selected from solid tumors, hematologic malignancies, and metastatic, refractory, or recurrent lesions of cancer.

[0034] 10. The use according to item 8, wherein the tumor is selected from the group consisting of: multiple myeloma, acute myeloid leukemia, non-small cell lung cancer (NSCLC), small cell lung cancer, colorectal cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, esophageal cancer, and kidney cancer.

[0035] 11. Use of an antibody-drug conjugate comprising any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, in combination with other therapeutic agents in the preparation of a medicament for the treatment and / or prevention of tumors.

[0036] 12. According to the use described in item 11, wherein the other therapeutic agent is selected from immune checkpoint drugs, anti-tumor monoclonal antibody drugs, anti-angiogenic drugs, kinase inhibitors, anti-tumor T-cell binding antibodies, synthetic lethal target drugs, drugs for chemotherapy, or drugs for radiotherapy.

[0037] 13. Use of an antibody-drug conjugate comprising any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, in the treatment and / or prevention of tumors.

[0038] 14. The use of an antibody-drug conjugate comprising any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, in combination with other therapeutic agents for the treatment and / or prevention of tumors.

[0039] 15. According to the use described in item 14, wherein the other therapeutic agent is selected from immune checkpoint drugs, anti-tumor monoclonal antibody drugs, anti-angiogenic drugs, kinase inhibitors, anti-tumor T-cell binding antibodies, synthetic lethal target drugs, drugs for chemotherapy, or drugs for radiotherapy.

[0040] 16. A method for treating and / or preventing tumors, wherein a subject is given a therapeutically effective amount of the antibody-drug conjugate described in any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof.

[0041] 17. The method according to item 16, wherein the tumor is selected from solid tumors, hematologic malignancies, and metastatic, refractory, or recurrent lesions of cancer;

[0042] Preferably, the tumor is selected from the group consisting of: multiple myeloma, acute myeloid leukemia, non-small cell lung cancer (NSCLC), small cell lung cancer, colorectal cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, esophageal cancer, and kidney cancer.

[0043] Preferably, other therapeutic drugs may also be administered simultaneously.

[0044] The antibody-drug conjugate described in this application has a high specificity binding ability to tumor cells expressing Lewis Y protein, thereby achieving excellent cell killing effect. Attached Figure Description

[0045] Figure 1 is a schematic diagram of Lewis Y antibody drug conjugates.

[0046] Figure 2 is a SEC analysis diagram of the Lewis Y antibody drug conjugate prepared in Example 2 of this application.

[0047] Figure 3 shows the binding activity of Lewis Y antibody drug conjugates on positive cells (T-47D) and negative cells (Colo205).

[0048] Figure 4 shows the therapeutic effect of Lewis Y antibody drug conjugate on tumors in the NCI-N87 mouse xenograft tumor model.

[0049] Figure 5 shows the immunohistochemical staining of normal human pancreatic tissue with Lewis Y antibody.

[0050] Figure 6 shows the immunohistochemical staining of normal pancreatic tissue from cynomolgus monkeys with Lewis Y antibody. Detailed Implementation

[0051] The following description provides exemplary embodiments of this application, including various details to aid understanding, and should be considered merely exemplary. Therefore, those skilled in the art will recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of this application. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0052] It should be noted that certain terms are used in the specification and claims to refer to specific components. Those skilled in the art will understand that different terms may be used to refer to the same component. This specification and claims do not distinguish components based on differences in terminology, but rather on differences in function. The terms "comprising" or "including" used throughout the specification and claims are open-ended and should be interpreted as "comprising but not limited to." The following descriptions in the specification are preferred embodiments for carrying out this application; however, these descriptions are for the purpose of understanding the general principles of the specification and are not intended to limit the scope of this application. The scope of protection of this application shall be determined by the appended claims.

[0053] This application provides an antibody drug conjugate, comprising the structure of Formula 1 below:

[0054] Wherein, Ab is an antibody or antibody fragment used to target Lewis Y;

[0055] j can be 1 to 8, preferably 4 to 8, for example, it can be 1, 2, 3, 4, 5, 6, 7, 8, etc.

[0056] In this application, the antibody or antibody fragment for targeting Lewis Y comprises three heavy chain complementarity-determining regions (CDR-H1, CDR-H2, and CDR-H3) and three light chain complementarity-determining regions (CDR-L1, CDR-L2, and CDR-L3), wherein:

[0057] The amino acid sequence of CDR-H1 is shown in SEQ ID NO: 1 or 13;

[0058] SEQ ID NO: 1 is GFTFSDYY.

[0059] SEQ ID NO: 13 is GYTFTDYN.

[0060] The amino acid sequence of CDR-H2 is shown in SEQ ID NO: 2, 7, 10 or 14;

[0061] SEQ ID NO: 2 is ISNGGGSS.

[0062] SEQ ID NO: 7 is ISQGGDIT.

[0063] SEQ ID NO: 10 is MSNVGAIT.

[0064] SEQ ID NO: 14 is IYPYQGYS.

[0065] The amino acid sequence of CDR-H3 is shown in SEQ ID NO: 3, 8, 11 or 15;

[0066] SEQ ID NO: 3 is ARGMDYGAWFAY.

[0067] SEQ ID NO: 8 is ARGLDDGAWFAY.

[0068] SEQ ID NO: 11 is ARGTRDGSWFAY.

[0069] SEQ ID NO: 15 is ARQLGPGTF.

[0070] The amino acid sequence of CDR-L1 is shown in SEQ ID NO: 4, 9, 12 or 16;

[0071] SEQ ID NO: 4 is QSIVHSNGNTY.

[0072] SEQ ID NO:9 is QIIVHNNGNTY.

[0073] SEQ ID NO: 12 is QRIVHSNGNTY.

[0074] SEQ ID NO: 16 is QSLLHGNGKTY.

[0075] The amino acid sequence of CDR-L2 is as shown in SEQ ID NO: 5 or 17;

[0076] SEQ ID NO: 5 is KVS.

[0077] SEQ ID NO: 17 is LVS.

[0078] The amino acid sequence of CDR-L3 is shown in SEQ ID NO: 6 or 18.

[0079] SEQ ID NO: 6 is FQGSHVPFT.

[0080] SEQ ID NO: 18 is LQATHFPLT.

[0081] In this application, the antibody or antibody fragment for targeting Lewis Y comprises a heavy chain variable region and a light chain variable region, wherein the amino acid sequence of the heavy chain variable region is as shown in SEQ ID NO: 19, 21, 23 or 25 or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 19, 21, 23 or 25;

[0082] The amino acid sequence of the light chain variable region is as shown in SEQ ID NO: 20, 22, 24 or 26, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 20, 22, 24 or 26.

[0083] In some embodiments, the antibody for targeting Lewis Y is 311, the amino acid sequence of its heavy chain variable region is SEQ ID NO: 19, and the amino acid sequence of its light chain variable region is SEQ ID NO: 20.

[0084] In some embodiments, the antibody targeting Lewis Y is BR96, the amino acid sequence of its heavy chain variable region is SEQ ID NO: 21, and the amino acid sequence of its light chain variable region is SEQ ID NO: 22.

[0085] In some embodiments, the antibody targeting Lewis Y is Hu3S193, the amino acid sequence of its heavy chain variable region is SEQ ID NO: 23, and the amino acid sequence of its light chain variable region is SEQ ID NO: 24.

[0086] In some embodiments, the antibody for targeting Lewis Y is 101, the amino acid sequence of its heavy chain variable region is SEQ ID NO: 25, and the amino acid sequence of its light chain variable region is SEQ ID NO: 26.

[0087] Table 1 shows the amino acid sequences of the three heavy chain complementarity-determining regions (CDR-H1, CDR-H2, and CDR-H3) and the three light chain complementarity-determining regions (CDR-L1, CDR-L2, and CDR-L3) of antibodies 311, BR96, Hu3S193, and 101 used to target Lewis Y.

[0088] Table 2 shows the amino acid sequences of the heavy chain and light chain variable regions of antibodies 311, BR96, Hu3S193, and 101 used to target Lewis Y.

[0089] In this application, the Ab is an antibody targeting LewisY, the heavy chain of the antibody is IgG1 subtype or mutated IgG1 subtype, and the light chain of the antibody is Kappa type.

[0090] In this application, the antibody for targeting LewisY comprises heavy and light chains.

[0091] In some embodiments, the amino acid sequence of the heavy chain is as shown in SEQ ID NO: 27, 29, 31 or 33, or has at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity with the amino acid sequence of SEQ ID NO: 27, 29, 31 or 33.

[0092] The amino acid sequence of the light chain is as shown in SEQ ID NO: 28, 30, 32 or 34, or has at least 80%, 81%, 82%, 83%, 84%, 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% identity with the amino acid sequence of SEQ ID NO: 28, 30, 32 or 34.

[0093] Table 3 shows the heavy and light chain amino acid sequences of antibodies 311, BR96, Hu3S193, and 101 used to target Lewis Y.

[0094] In this application, the antibody targeting Lewis Y is able to bind to Lewis Y with sufficient affinity, such that the antibody targeting Lewis Y can be used as a diagnostic and / or therapeutic agent targeting Lewis Y.

[0095] The antibody targeting Lewis Y in this application does not bind to proteins unrelated to the target. Here, "unrelated protein" refers to proteins other than Lewis Y, which is the target; and "does not bind" means that, if the binding ability of the antibody targeting Lewis Y in this application to Lewis Y as its target is taken as 100%, the binding ability of the antibody targeting Lewis Y in this application to the unrelated protein is less than 10%, for example, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, or 0%.

[0096] The antibody used in this application to target Lewis Y is a monoclonal antibody.

[0097] The structure of the Lewis Y antigen is: Fucα2Galβ4(Fucα3)GlcNAc-α, as shown in the following diagram:

[0098] In this application, "antibody" refers to a whole antibody, or may also be called a complete antibody or intact antibody. An antibody is a glycoprotein containing at least two heavy chains (HC) and two light chains (LC) linked by disulfide bonds. Each heavy chain consists of a heavy chain variable region (VH) and a heavy chain constant region. The heavy chain constant region consists of three domains (CH1, CH2, and CH3). Each light chain consists of a light chain variable region (VL) and a light chain constant region. The light chain constant region consists of one domain (CL). The VH and VL regions can be further subdivided into highly variable regions called complementarity-determining regions (CDRs), interspersed with more conserved regions called backbone regions (FRs). Each VH and VL consists of three CDRs and four FRs arranged in the following order from the amino terminus to the carboxyl terminus: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. The variable regions of the heavy and light chains contain binding domains that interact with the antigen. The constant region of an antibody mediates the binding of immunoglobulins to host tissues or factors, including various cells of the immune system (e.g., effector cells) and the first component (CIq) of the classical complement system. In this application, the term "antibody" has its broadest meaning, encompassing immunoglobulin molecules and immunologically active fragments of immunoglobulin molecules, i.e., molecules containing antigen-binding sites or domains, and can be used to refer to antigen-binding structural fragments (e.g., antigen-binding fragments) or complexes of one or more antigen-binding fragments (e.g., scFv). Immunoglobulin molecules can be of any class (e.g., IgG, IgE, IgM, IgD, IgA, and IgY), or any type (e.g., IgG1, IgG2, IgG3, IgG4, IgA1, and IgA2), or any subclass, or of any origin (e.g., human, mouse, rabbit, camel, fish, etc.).

[0099] In this application, "antigen-binding fragment" or "antibody fragment" refers to one or more fragments of an antibody that retain the ability to specifically bind to a given antigen and thereby exhibit the desired antigen-binding activity. The antigen-binding function of an antibody can be performed by fragments of the complete antibody. Examples of binding fragments covered by the term "antigen-binding fragment of an antibody" include, but are not limited to, examples of the following antibody fragments, including but not limited to: Fab, Fab', Fab'-SH, F(ab')2; bisomatic antibodies; linear antibodies; single-chain antibody molecules (e.g., scFv and scFab); single-domain antibodies (dAbs); and multispecific antibodies formed from antibody fragments; Fd fragments consisting of VH and CH1 domains; Fv fragments consisting of VL and VH domains of an antibody arm; single-domain antibody (dAb) fragments consisting of either a VH domain or a VL domain; and isolated complementarity-determining regions (CDRs). Furthermore, although the two domains VL and VH of the Fv fragment are encoded by separate genes, they can be linked via artificial peptide linkers using recombinant methods, enabling them to become a single protein chain where the VL and VH regions pair to form a monovalent molecule (called a single-chain Fv (scFv)). These single-chain antibodies may include one or more antigen-binding fragments of the antibody. These antigen-binding fragments are obtained using conventional techniques known to those skilled in the art, and the usability of the fragments is screened in the same manner as for intact antibodies. Antigen-binding fragments can also be incorporated into single-domain antibodies, large antibodies, micro antibodies, intracellular antibodies, bisomal antibodies, trisomal antibodies, tetrasomal antibodies, v-NARs, and bis-scFvs. Antigen-binding fragments can be incorporated into single-chain molecules containing a pair of tandem Fv fragments (VH-CH1-VH-CH1), forming a pair of antigen-binding regions together with a complementary light chain polypeptide. "Antibodies" include polyclonal antibodies and monoclonal antibodies.

[0100] In this application, the “Fd” fragment consists of VH and CH1 domains. The “dAb” fragment (Ward et al., (1989) Nature 341:544-546) consists of a VH domain. Separate complementarity-determining regions (CDRs) and combinations of two or more separate CDRs can optionally be joined by a synthetic linker.

[0101] In this application, the "Fv" fragment consists of the VL and VH domains of the antibody single arm. The single-chain Fv (scFv) consists of a heavy chain variable region and a light chain variable region, which are covalently linked into a single-chain polypeptide chain by a flexible peptide linker.

[0102] In this application, "monoclonal antibody" refers to an antibody of a substantially homologous group of antibodies, meaning that the individual antibodies constituting the group are identical and / or bind to the same epitope, except for possible variant antibodies (e.g., containing naturally occurring mutations or generated during the production of monoclonal antibody articles), which are typically present in trace amounts. Unlike polyclonal antibody articles, which typically comprise different antibodies targeting different determinants (epitopes), each monoclonal antibody in a monoclonal antibody article targets a single determinant on an antigen. Therefore, the modifier "monoclonal" indicates that the antibody is derived from a substantially homologous group of antibodies and should not be construed as requiring the antibody to be produced by any particular method. For example, the monoclonal antibody used according to this application can be prepared by a variety of techniques, including, but not limited to, hybridoma methods, recombinant DNA methods, phage display methods, and methods using transgenic animals containing all or part of human immunoglobulin loci, such methods and other exemplary methods for preparing monoclonal antibodies are described herein.

[0103] In this application, "monoclonal antibody" generally refers to a human antibody, which can be prepared using techniques known to those skilled in the art. For example, human antibodies are generally described in van Dijk, MA and van de Winkel, JG, Curr. Opin. Pharmacol. 5:368-374 (2001) and Lonberg, N., Curr. Opin. Immunol. 20:450-459 (2008).

[0104] The monoclonal antibodies described in this application may also be antibody variants, for example, where improved binding affinity and / or other biological properties of the antibody may be desired. Amino acid sequence variants of the antibody can be prepared by introducing suitable modifications into the nucleotide sequence encoding the antibody, or by peptide synthesis. Such modifications include, for example, deletion, and / or insertion and / or substitution of residues within the amino acid sequence of the antibody. Any combination of deletion, insertion, and substitution can be performed to obtain the final construct, provided that the final construct possesses the desired characteristics, such as antigen binding. Thus, in some embodiments, antibody variants with one or more amino acid substitutions are provided, where the sites of interest for substitution mutation include HVR and FR. For example, amino acid substitutions can be introduced into the antibody of interest and products with desired activities can be screened, such as retained / improved antigen binding, reduced immunogenicity, or improved ADCC or CDC.

[0105] In this application, the Fc region of the antibody whose heavy chain is the IgG1 subtype is different from that of the antibody whose heavy chain is the mutated IgG1 subtype, but the variable regions are the same. That is, the variable regions of the heavy chain and the variable regions of the light chain of the two antibodies are the same.

[0106] In this application, the antibody component or antibody in the antibody-drug conjugate comprises a human-derived Fc domain (Fc region) and all other portions of a preferably human constant region. As used herein, the term "human-derived Fc domain" means an Fc domain that is the Fc domain of a human antibody of the IgG1, IgG2, IgG3, or IgG4 subclass, preferably an Fc domain of the human IgG1 subclass or a mutant Fc domain of the human IgG1 subclass. The antibody has reduced or minimal effector function. Minimal effector function is caused by an effectorless Fc mutation.

[0107] In this application, the term "Fc region" is used to define a C-terminal region in an immunoglobulin heavy chain that contains at least a portion of a constant region, including both native and variant Fc regions. In some embodiments, the human IgG heavy chain Fc region extends from Cys226 or Pro230 to the C-terminus of the heavy chain. However, antibodies produced by host cells may undergo post-translational cleavage of one or more (particularly one or two) amino acids from the C-terminus of the heavy chain. Therefore, antibodies produced by host cells by expressing a specific nucleic acid molecule encoding the full-length heavy chain may comprise the full-length heavy chain, or the antibody may comprise a cleaved variant of the full-length heavy chain. This may be the case when the last two C-terminal amino acids of the heavy chain are glycine (G446) and lysine (K447, according to the Kabat EU index number). Therefore, the C-terminal lysine (Lys447) or the C-terminal glycine (Gly446) and lysine (Lys447) of the Fc region may or may not be present. In some embodiments, the heavy chain including the Fc region (subunit) as specified herein is included in the antibody according to this application. Unless otherwise specified herein, the amino acid residues in the Fc region or constant region are numbered according to the EU numbering system (also known as the EU index), as described in Kabat et al., Sequences of Proteins of Immunological Interest, 5th edition, Public Health Service, National Institutes of Health, Bethesda, MD, 1991 (see also above). As used herein, a “subunit” of the Fc domain refers to one of two polypeptides forming a dimer Fc domain, namely a polypeptide containing the C-terminal constant region of the immunoglobulin heavy chain that is stably self-associating. For example, the subunit of the IgG Fc domain contains an IgG CH2 constant domain and an IgG CH3 constant domain.

[0108] In this application, "variable region," also known as "variable domain," refers to the domain of the antibody heavy or light chain involved in antibody-antigen binding. The variable domains (VH and VL, respectively) of the heavy and light chains of natural antibodies typically have similar structures, with each domain containing four conserved frame regions (FRs) and three hypervariable regions (HVRs). See, for example, Kindt et al., Kuby Immunology, 6th ed., WH Freeman and Co., p. 91 (2007). A single VH or VL domain may be sufficient to confer antigen-binding specificity.

[0109] In this application, the terms "host cell," "host cell line," and "host cell culture" are used interchangeably and refer to cells in which exogenous nucleic acids have been introduced, including progeny cells of such cells. Host cells include "transformers" and "transformed cells," which include primary transformed cells and progeny derived from said primary transformed cells, regardless of passage number. Progeny may not be identical to the nucleic acid contents of the parent cells and may contain mutations. This includes mutant progeny with the same function or biological activity as screened or selected in the original transformed cells. Host cells are any type of cell system that can be used to produce antibodies of the present invention. Host cells include cultured cells, such as cultured mammalian cells, such as, to name just a few, HEK cells, CHO cells, BHK cells, NSO cells, SP2 / 0 cells, YO myeloma cells, P3X63 mouse myeloma cells, PER cells, PER.C6 cells, or hybridoma cells, yeast cells, insect cells, and plant cells, as well as cells contained in transgenic animals, transgenic plants, or cultured plant or animal tissues. In one aspect, the host cells of the present invention are eukaryotic cells, particularly mammalian cells. In one respect, the host cell is not a cell within the human body.

[0110] In this application, "affinity" refers to the strength of the sum of non-covalent interactions between a single binding site of a molecule (e.g., an antibody) and its binding partner (e.g., an antigen). Unless otherwise indicated, "binding affinity" as used herein refers to the intrinsic binding affinity reflecting a 1:1 interaction between members of a binding pair (e.g., antibody and antigen). The affinity of molecule X for its partner Y can generally be represented by the equilibrium dissociation constant (KD). Affinity can be measured using common methods known in the art.

[0111] This application provides a method for preparing an antibody drug conjugate, comprising the following steps:

[0112] Step 1: Provide LD-38;

[0113] Step 2: Construct an antibody or antibody fragment Ab for targeting Lewis Y;

[0114] Step 3: Conjugate LD-38 with an antibody or antibody fragment Ab targeting Lewis Y to obtain an antibody-drug conjugate;

[0115] The structure of LD-38 is as follows

[0116] The antibody or antibody fragment Ab used to target Lewis Y is as described above.

[0117] This application provides a pharmaceutical composition comprising the aforementioned antibody-drug conjugate, or its tautomers, mesosomes, racemates, enantiomers, diastereomers, or mixtures thereof, or its pharmaceutically acceptable salts, prodrugs, or solvates.

[0118] This application also provides the use of the aforementioned antibody-drug conjugate, or its tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or its pharmaceutically acceptable salt, prodrug, or solvate, in the preparation of a medicament for the treatment and / or prevention of tumors.

[0119] The tumor is selected from metastatic, refractory, or recurrent lesions of solid tumors, hematologic malignancies, and cancers.

[0120] The tumors are selected from the following groups: multiple myeloma, acute myeloid leukemia, non-small cell lung cancer (NSCLC), small cell lung cancer, colorectal cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, esophageal cancer, and kidney cancer.

[0121] This application also provides the use of the antibody-drug conjugate, or its tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or its pharmaceutically acceptable salt, prodrug, or solvate, in combination with other therapeutic agents in the preparation of a medicament for the treatment and / or prevention of tumors.

[0122] The other therapeutic agents are selected from immune checkpoint inhibitors, anti-tumor monoclonal antibody drugs, anti-angiogenic drugs, kinase inhibitors, anti-tumor T-cell binding antibodies, synthetic lethal target drugs, drugs used for chemotherapy, or drugs used for radiotherapy.

[0123] This application also provides the use of the antibody-drug conjugate, or its tautomers, mesosomes, racemates, enantiomers, diastereomers, or mixtures thereof, or its pharmaceutically acceptable salts, prodrugs, or solvates, in the treatment and / or prevention of tumors.

[0124] This application also provides the use of the antibody-drug conjugate, or its tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or its pharmaceutically acceptable salt, prodrug, or solvate, in combination with other therapeutic agents for the treatment and / or prevention of tumors.

[0125] The other therapeutic agents are selected from immune checkpoint inhibitors, anti-tumor monoclonal antibody drugs, anti-angiogenic drugs, kinase inhibitors, anti-tumor T-cell binding antibodies, synthetic lethal target drugs, drugs used for chemotherapy, or drugs used for radiotherapy.

[0126] This application also provides a method for treating and / or preventing tumors, wherein a therapeutically effective amount of an antibody-drug conjugate, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, is administered to a subject.

[0127] The tumor is selected from metastatic, refractory, or recurrent lesions of solid tumors, hematologic malignancies, and cancers.

[0128] Furthermore, the tumor is selected from the group consisting of multiple myeloma, acute myeloid leukemia, non-small cell lung cancer (NSCLC), small cell lung cancer, colorectal cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, esophageal cancer, and kidney cancer.

[0129] Furthermore, other therapeutic agents may be administered concurrently when administering antibody drug conjugates, or their tautomers, mesosomes, racemates, enantiomers, diastereomers, or mixtures thereof, or their pharmaceutically acceptable salts, prodrugs, or solvates.

[0130] The other therapeutic agents are selected from immune checkpoint inhibitors, anti-tumor monoclonal antibody drugs, anti-angiogenic drugs, kinase inhibitors, anti-tumor T-cell binding antibodies, synthetic lethal target drugs, drugs used for chemotherapy, or drugs used for radiotherapy.

[0131] In this application, "pharmaceutical composition" means a mixture containing one or more of the compounds described herein or their physiologically pharmaceutically acceptable salts or prodrugs, along with other chemical components, such as physiologically pharmaceutically acceptable carriers and excipients. The purpose of a pharmaceutical composition is to facilitate administration to a living organism, thereby promoting the absorption of the active ingredient and the exertion of its biological activity.

[0132] In this application, "treatment" (and its grammatical variations) refers to an attempt to alter the natural course of a disease in the treated individual, and is a clinical intervention that can be performed for prevention or may be performed during a clinicopathological process. The desired effects of treatment include, but are not limited to, preventing the onset or recurrence of disease, alleviating symptoms, weakening any direct or indirect pathological consequences of the disease, preventing metastasis, slowing the rate of disease progression, improving or alleviating the disease state, and mitigating or improving prognosis. In some aspects, the antibodies of this application are intended to delay the development of disease or slow its progression.

[0133] In this application, "individual" or "subject" is a mammal. Mammals include, but are not limited to, domesticated animals (e.g., cattle, sheep, cats, dogs, and horses), primates (e.g., human and non-human primates, such as monkeys), rabbits, and rodents (e.g., mice and rats). In some respects, the individual or subject is a human.

[0134] Example

[0135] The materials and test methods used in the embodiments of this application are described in a general and / or specific manner. In the following embodiments, unless otherwise specified, % means wt%, i.e., weight percentage. Reagents or instruments used, unless otherwise specified, are all commercially available conventional reagent products.

[0136] Example 1: Preparation of LD-38

[0137] The synthetic route for LD-38 is as follows:

[0138] Synthesis of 38-1

[0139] Fmoc-L-glutamic acid-5-tert-butyl ester (144.7 mg, 1.175 mmol) and 4-aminobenzyl alcohol (500 mg, 1.175 mmol) were dissolved in 3 mL of anhydrous DMF. DIEA (303.7 mg, 2.350 mmol) and HATU (536.19 mg, 1.410 mmol) were added, and the mixture was stirred at room temperature for 16 hours. LC-MS showed the reaction was complete. Water was added, and the mixture was extracted three times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. Purification was performed using a normal-phase silica gel column (EA / PE, 0% to 45%) to obtain 530 mg. MS(+) = 475.2.

[0140] Synthesis of 38-2

[0141] Compound 38-1 (530 mg, 0.999 mmol) was dissolved in 3 mL of anhydrous DMF, and piperidine (0.2 mL) was added to the reaction solution. The mixture was stirred at room temperature for one hour. The solution was concentrated to obtain 600 mg of crude product, which was used directly in the next step of the reaction. MS(+) = 309.2.

[0142] Synthesis of 38-3

[0143] Compound 38-2 (600 mg crude) and Fmoc-L-valine (500 mg, 1.175 mmol) were dissolved in 3 mL of anhydrous DMF. DIEA (334.13 mg, 2.585 mmol) and HATU (589.82 mg, 1.551 mmol) were added, and the mixture was stirred at room temperature for 16 hours. LC-MS showed the reaction was complete. Water was added, and the mixture was extracted three times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. Purification was performed using a normal-phase silica gel column (EA / PE, 40% to 60%) to give 450 mg, 6.MS(+) = 630.4.

[0144] Synthesis of 38-4

[0145] Compound 38-3 (450 mg, 0.715 mmol) was dissolved in 1 mL of anhydrous DCM and 4 mL of anhydrous DMF. Di(p-nitrobenzene) carbonate (869.5 mg, 2.858 mmol) and 0.354 mL of DIEA were added sequentially. After reacting at room temperature for 12 hours, water was added to the reaction solution, and the mixture was extracted three times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. Purification was performed using a normal-phase silica gel column (EA / PE, 30% to 70%) to obtain 200 mg. MS(+) = 543.2.

[0146] Synthesis of 38-5

[0147] Compound 38-4 (100 mg, 0.126 mmol) and eczematidine mesylate (54.78 mg, 0.126 mmol) were dissolved in 2 mL of anhydrous DMF. DMAP (0.15 mg, 0.0001 mmol) and DIEA (32.52 mg, 0.252 mmol) were added sequentially. After reacting at room temperature for 1 hour, water was added to the reaction mixture, and the mixture was extracted three times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. Purification was performed using a normal-phase silica gel column (EA / PE, 30% to 70%) to obtain 100 mg. MS(+) = 1091.4.

[0148] Synthesis of 38-6

[0149] Compound 38-5 (100 mg, 0.073 mmol) was dissolved in 3 mL of anhydrous DMF, and piperidine (0.3 mL) was added to the reaction solution. The mixture was stirred at room temperature for one hour. The solution was concentrated to obtain 110 mg of crude product, which was used directly in the next step of the reaction. MS(+) = 870.8.

[0150] Synthesis of 38-7

[0151] Compound 38-6 (110 mg crude) and Mal-amido-PEG4-acid (30.19 mg, 0.073 mmol) were dissolved in 2 mL of anhydrous DMF. DIEA (18.74 mg, 0.145 mmol) and HATU (33.08 mg, 0.087 mmol) were added, and the mixture was stirred at room temperature for 2 hours. LC-MS showed the reaction was complete. Water was added, and the mixture was extracted three times with ethyl acetate. The combined organic phases were washed with saturated brine, dried over anhydrous sodium sulfate, filtered, and concentrated to obtain the crude product. Purification was performed using a normal-phase silica gel column (MeOH / DCM, 5% to 20%) to give 90 mg. MS(+) = 1267.6.

[0152] Synthesis of 38-8

[0153] Compound 38-7 (90 mg, 0.071 mmol) was dissolved in 3 mL of anhydrous DCM, and 0.3 mL of TFA was added. The mixture was stirred at room temperature for 2 hours. The crude product was concentrated to 80 mg and used directly in the next reaction. MS(+) = 2111.4.

[0154] Synthesis of LD-38

[0155] Compound 38-8 (80 mg, crude) and sulfonic acid quaternary ammonium salt A (13.89 mg, 0.066 mmol, CAS No.: 78276-19-4, provided by Shanghai Haoyuan Pharmaceutical Co., Ltd., synthetic method according to WO2011146595A2) were dissolved in 2 mL of anhydrous DMF. DIEA (17.07 mg, 0.132 mmol) and HATU (30.14 mg, 0.079 mmol) were added, and the mixture was stirred at room temperature for 1 hour. LC-MS showed that the reaction was complete. Purification was performed by reverse-phase preparation (mobile phase containing 0.1% formic acid) to give 13.5 mg of a white solid.

[0156] LCMS: m / z(ES+)(M+H)+=1404.6, Rt=1.314min

[0157] 1H NMR (400MHz, DMSO) δ9.89(s,1H),8.18(d,J=7.2Hz,2H),8.10–7.93(m,3H),7.78(d,J=10.8Hz,1H),7.63(d,J= 8.4Hz,2H),7.37(d,J=8.4Hz,2H),7.32(s,1H),6.99(s,2H),6.53(s,1H),5.45(s,2H),5.29(d,J=4.Hz,3H),5 .08(s,2H),4.32(dd,J=13.2,7.6Hz,1H),4.20–4.14(m,1H),3.59(dd,J=14.8,7.6Hz,6H),3.40-3.51(m,18H) ,3.14-3.20(m,4H),3.03(s,7H),2.42-2.30(m,7H),2.20-2.31(m,4H),2.03-1.82(m,8H),0.87-0.91(m,9H).

[0158] Example 2 Preparation of Antibody-Drug Conjugates (ADCs)

[0159] Antibodies 311, BR96, Hu3S193, and 101 are anti-LewisY monoclonal antibodies, with the Fc region employing the IgG1 subtype. The amino acid sequences of these antibodies are shown in Tables 1-3. Antibodies 311, BR96, Hu3S193, and 101 were obtained by constructing codon-optimized heavy and light chain nucleotide sequences into the PCDNA3.4 expression plasmid, followed by transient transfection of CHO cells, and purification of the expression supernatant using Protein A affinity.

[0160] The antibody was transferred to pH 7.4 phosphate buffer using an ultrafiltration centrifuge tube, and 12 times the molar amount of tris(2-carboxyethyl)phosphine hydrochloride (TCEP) was added. The reaction was carried out at 37°C for 2 hours to open the interchain disulfide bonds of the antibody. After reduction, the antibody was transferred to pH 7.4 phosphate buffer again using an ultrafiltration centrifuge tube to remove excess TCEP. 12 times the molar amount of LD-38 was added, and the reaction was carried out at room temperature for 1 hour. After the reaction, 2 times the molar amount of LD-38 was added to quench the reaction, and the solution was transferred to pH 5.5 acetate-sodium acetate (40 mM) buffer using an ultrafiltration centrifuge tube. The ADC sample after solution transfer was filtered through a 0.22 μm sterile filter to obtain the antibody-drug conjugate with a DAR value of 8 (Figure 1). The purity of the antibody-drug conjugate was measured by size exclusion chromatography (SEC).

[0161] Size exclusion chromatography (SEC) was performed using a Tskgel G3000SWXL (TOSOH, 0008541) column with a mobile phase of 0.1M PB pH 7.0 and 0.1M NaCl. Isocratic elution was used at a flow rate of 1 mL / min and a column temperature of 25℃. Detection wavelengths were 280 nm and 366 nm. The SEC analysis results are shown in Figure 2, which includes Figures 2(A), 2(B), 2(C), and 2(D). As shown in Figure 2, the purities of the LD-38 conjugates of 311, BR96, Hu3S193, and 101 are all >98%.

[0162] Example 3: Determination of ADC binding at the cellular level by flow cytometry

[0163] Lewis Y-positive T-47D cells and Lewis Y-negative Colo205 cells were revived and cultured in DMEM + 10% FBS and RPMI 1640 + 10% FBS medium, respectively, in an incubator at 37°C and 5% CO2. Colo205 cells were semi-adherent, while T-47D cells were adherent. When cell confluence was greater than 80%, cells were passaged at a ratio of 1:3 to 1:10.

[0164] Recombinant enzyme digestion solution (TrypLE) TM T-47D and Colo205 cells were digested separately using Express Enzyme. After counting, an appropriate amount of cell suspension was centrifuged and washed once with FACS dilution buffer (PBS + 1% FBS). The cell density was then adjusted to 1.5 × 10⁻⁶ cells / year. 6Cells were added at a concentration of 100 μL / well to 96-well U-shaped plates. Anti-LewisY antibody conjugates 311-LD-38, BR96-LD-38, Hu3S193-LD-38, and 101-LD-38 were serially diluted 5-fold from 600 nM (final concentration 300 nM) using FACS dilution buffer, resulting in 8 concentration points. The isotype control IgG1-LD-38 (isotype control IgG1 antibody purchased from Sinobio, catalog number: HG1K) was serially diluted 5-fold from 600 nM (final concentration 300 nM) using FACS dilution buffer, resulting in 4 concentration points. A blank control with a sample concentration of 0 was also included. The diluted samples were added at 100 μL / well to 96-well U-shaped plates containing cells. Cells and samples were incubated at 4°C for 1 hour, centrifuged at 1000 rpm for 3 min, and the cells were washed once with FACS dilution buffer. The secondary antibody (Goat anti-human IgG Fc PE) was diluted 1:50 with FACS dilution buffer, and 100 μL / well was added to 96-well U-shaped plates containing cells. The secondary antibody and cells were incubated at 4°C for 45 minutes, centrifuged at 1000 rpm for 3 minutes, and the cells were washed twice with FACS dilution buffer. Finally, the cells were resuspended in 150 μL of FACS dilution buffer. The MFI (Median Fluorescent Intensity) and cell positivity rate of each sample were detected by flow cytometry.

[0165] The results are shown in Figure 3, which includes Figures 3(A), 3(B), 3(C), and 3(D). All four anti-Lewis Y antibody drug conjugates bound to the Lewis Y-positive cell line T-47D in a concentration-dependent manner, with EC50 values ​​of 35.920 nM, 3.501 nM, 3.640 nM, and 9.441 nM, respectively. BR96-LD-38 showed strong nonspecific binding to the Lewis Y-negative cell line Colo205, as evidenced by both the intensity of binding fluorescence and the number of positive cells. 311-LD-38, Hu3S193-LD-38, and 101-LD-38 showed relatively weak nonspecific binding to the Lewis Y-negative cell line Colo205, and this binding was only observed in the number of positive cells.

[0166] Example 4: In vivo efficacy

[0167] To verify the in vivo efficacy of the anti-Lewis Y antibody-drug conjugate, a mouse tumor xenograft model was established. Human gastric cancer cell line NCI-N87, grown to the logarithmic growth phase, was digested with EDTA and resuspended in PBS. Each mouse (5-6 week old female Balb / c Nude mouse) was subcutaneously inoculated with 5 × 10⁵ cells. 6Cells, when the average tumor volume reaches approximately 150-200 mm 3 Animals were randomly assigned to different groups based on tumor volume. Each group consisted of 6 mice. Intravenous administration of 2.5 mg / kg was administered once, and observations were made after each administration. The specific protocol is shown in Table 4 below. The main observation indicators of this experiment were: 1) TGI (%), calculated using the formula TGI (%) = (1-T / C) × 100% (T and C are the relative tumor volumes of the treatment group and the control group at a specific time point, respectively; T is T26-T0, and C is C26-C0); 2) tumor volume at the experimental endpoint; and 3) mouse body weight at the experimental endpoint.

[0168] Table 4. Tumor therapeutic efficacy of anti-Lewis Y ADC in NCI-N87 xenograft tumor model

[0169] The experimental results are shown in Table 4 and Figure 4. Hu3S193-LD-38 and BR96-LD-38 both showed good tumor inhibition effects in mice. On day 26 after a single administration, the tumor inhibition rates reached 109.35% and 112.67%, respectively, which were significantly different from the control group.

[0170] Example 5 Immunohistochemistry

[0171] Normal pancreatic tissues from cynomolgus monkeys and humans were embedded in paraffin and sectioned to a thickness of 3 μm. After baking at 60°C for 2 hours, the sections were allowed to equilibrate to room temperature, then dewaxed and hydrated using xylene, graded ethanol, and PBS, respectively. Heat retrieval was performed using Tris-EDTA (pH 9.0) antigen retrieval buffer (95°C-99°C) for 20 minutes, followed by natural cooling to room temperature and washing with PBS for 10 minutes. Then, endogenous peroxidase inhibitors were added and the sections were incubated at room temperature for 10 minutes. After washing three times with PBS, 5% BSA blocking buffer was added and incubated at room temperature for 1 hour. BR96 and Hu3S193 antibodies were then diluted with 1% BSA-PBS to concentrations of 1 μg / mL-2 μg / mL, with human IgG1 isotype control antibody used as a negative control. The sections were incubated overnight at 4°C. On the second day, the slides were washed three times with PBS, and HRP-labeled goat anti-human IgG (Fab)2 (Jackson, catalog number: 109-035-097) diluted 1:500 with 1% BSA-PBS was added and incubated at room temperature for 1 hour. After washing three times with PBS, DAB (Vector, catalog number: SK-4105) was used for staining for about 5 minutes, and then tap water was used to stop the staining. After differentiation with hydrochloric acid-ethanol solution for 5 seconds, the slides turned blue with running tap water for 10 minutes. After dehydration with graded alcohol and clearing with xylene, the slides were mounted with mounting medium. The slides were examined under a microscope, and the staining results were semi-quantitatively analyzed.

[0172] The results are shown in Figures 5 and 6 and Table 5 below. Within the concentration range of 1 μg / mL to 2.5 μg / mL, the immunohistochemical staining intensity of BR96 on normal cynomolgus monkey pancreatic tissue and normal human pancreatic tissue was significantly stronger than that of HuS193. This is consistent with the strong non-specific binding of BR96 ADC at the cellular level in Example 3.

[0173] Table 5. Immunohistochemical staining of anti-Lewis Y antibody on normal pancreatic tissues of cynomolgus monkeys and humans

[0174] The above description is merely a preferred embodiment of this application and is not intended to limit the application in any other way. Any person skilled in the art may make changes or modifications to the disclosed technical content to create equivalent embodiments. However, any simple modifications, equivalent changes, and modifications made to the above embodiments based on the technical essence of this application without departing from the scope of the technical solution of this application shall still fall within the protection scope of this application.

Claims

1. An antibody-drug conjugate, wherein, Includes the structure of Equation 1 as follows: Wherein, Ab is an antibody or antibody fragment used to target Lewis Y; j can be 1 to 8, preferably 4 to 8.

2. The antibody-drug conjugate according to claim 1, wherein, The antibody or antibody fragment for targeting Lewis Y comprises three heavy chain complementarity-determining regions (CDR-H1, CDR-H2, and CDR-H3) and three light chain complementarity-determining regions (CDR-L1, CDR-L2, and CDR-L3), wherein: The amino acid sequence of CDR-H1 is shown in SEQ ID NO: 1 or 13; The amino acid sequence of CDR-H2 is shown in SEQ ID NO: 2, 7, 10 or 14; The amino acid sequence of CDR-H3 is shown in SEQ ID NO: 3, 8, 11 or 15; The amino acid sequence of CDR-L1 is shown in SEQ ID NO: 4, 9, 12 or 16; The amino acid sequence of CDR-L2 is shown in SEQ ID NO: 5 or 17; The amino acid sequence of CDR-L3 is shown in SEQ ID NO: 6 or 18.

3. The antibody-drug conjugate according to claim 1, wherein, The antibody or antibody fragment used to target LewisY comprises a heavy chain variable region and a light chain variable region, wherein, The amino acid sequence of the heavy chain variable region is as shown in SEQ ID NO: 19, 21, 23 or 25, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 19, 21, 23 or 25. The amino acid sequence of the light chain variable region is as shown in SEQ ID NO: 20, 22, 24 or 26, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 20, 22, 24 or 26.

4. The antibody-drug conjugate according to any one of claims 1-3, wherein, The Ab is an antibody targeting Lewis Y, wherein the heavy chain of the antibody is IgG1 subtype or mutated IgG1 subtype, and the light chain of the antibody is Kappa type.

5. The antibody-drug conjugate according to claim 4, wherein, The antibody targeting Lewis Y comprises a heavy chain and a light chain, wherein, The amino acid sequence of the heavy chain is as shown in SEQ ID NO: 27, 29, 31 or 33, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 27, 29, 31 or 33. The amino acid sequence of the light chain is as shown in SEQ ID NO: 28, 30, 32 or 34, or has at least 90%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or 100% identity with the amino acid sequence of SEQ ID NO: 28, 30, 32 or 34.

6. A method for preparing an antibody-drug conjugate, wherein, Includes the following steps: LD-38 is available; Construct antibodies or antibody fragments (Abs) for targeting Lewis Y; LD-38 is conjugated with an antibody or antibody fragment Ab for targeting Lewis Y to obtain an antibody-drug conjugate. The structure of LD-38 is as follows The antibody or antibody fragment Ab used to target Lewis Y is as described in claims 1-5.

7. A pharmaceutical composition, wherein, It includes the antibody drug conjugate as described in any one of claims 1-5, or its tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or its pharmaceutically acceptable salt, prodrug, or solvate.

8. Use of an antibody-drug conjugate comprising any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, in the preparation of a medicament for the treatment and / or prevention of tumors.

9. The use according to claim 8, wherein, The tumor is selected from metastatic, refractory, or recurrent lesions of solid tumors, hematologic malignancies, and cancers.

10. The use according to claim 8, wherein, The tumors are selected from the following groups: multiple myeloma, acute myeloid leukemia, non-small cell lung cancer (NSCLC), small cell lung cancer, colorectal cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, esophageal cancer, and kidney cancer.

11. Use of an antibody-drug conjugate comprising any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, in combination with other therapeutic agents in the preparation of a medicament for the treatment and / or prevention of tumors.

12. The use according to claim 11, wherein, The other therapeutic agents are selected from immune checkpoint inhibitors, anti-tumor monoclonal antibody drugs, anti-angiogenic drugs, kinase inhibitors, anti-tumor T-cell binding antibodies, synthetic lethal target drugs, drugs used for chemotherapy, or drugs used for radiotherapy.

13. Use of an antibody-drug conjugate comprising any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, for the treatment and / or prevention of tumors.

14. Use of an antibody-drug conjugate comprising any one of claims 1-5, or a tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof, in combination with other therapeutic agents for the treatment and / or prevention of tumors.

15. The use according to claim 14, wherein, The other therapeutic drugs are selected from immune checkpoint inhibitors, anti-tumor monoclonal antibody drugs, anti-angiogenic drugs, kinase inhibitors, anti-tumor T-cell binding antibodies, synthetic lethal target drugs, drugs used in chemotherapy, or drugs used in radiotherapy.

16. A method for treating and / or preventing tumors, wherein, The subject is given a therapeutically effective amount of the antibody-drug conjugate of any one of claims 1-5, or its tautomer, meso compound, racemic compound, enantiomer, diastereomer, or mixture thereof, or a pharmaceutically acceptable salt, prodrug, or solvate thereof.

17. The method according to claim 16, wherein, The tumor is selected from metastatic, refractory, or recurrent lesions of solid tumors, hematologic malignancies, and cancers. Preferably, the tumor is selected from the group consisting of: multiple myeloma, acute myeloid leukemia, non-small cell lung cancer (NSCLC), small cell lung cancer, colorectal cancer, breast cancer, ovarian cancer, pancreatic cancer, gastric cancer, esophageal cancer, and kidney cancer. Preferably, other therapeutic drugs may also be administered simultaneously.

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