Combination therapy of cancer using CD24 antibodies and PD-1-PD-l1 pathway

Abstract

The present application relates to a composition comprising i) an antibody or an antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or an antigen-binding portion thereof capable of blocking PD-1-PD-L1 binding / interaction, and the use of the composition in the treatment of cancer. The present application also relates to a cancer combination therapy using i) an antibody, or an antigen-binding portion thereof, that specifically binds to CD24, and ii) an antibody, or an antigen-binding portion thereof, that is capable of blocking PD-1-PD-L1 binding / interaction.

Description

Cancer combination therapy using CD24 antibodies and PD-1-PD-L1 pathway blocking antibodies

[0001] This application claims priority to Chinese patent application 202211568698.8 filed on December 7, 2022. Field of the Invention

[0002] The present application relates to the combined use of a CD24 antibody, or an antigen-binding portion thereof, and an antibody, or an antigen-binding portion thereof, capable of blocking PD-1-PD-L1 binding / interaction in the treatment of cancer. Specifically, the present application relates to a composition comprising i) an antibody, or an antigen-binding portion thereof, that specifically binds to CD24, and ii) an antibody, or an antigen-binding portion thereof, that can block PD-1-PD-L1 binding / interaction, and the use of the composition in the treatment of cancer and / or in the preparation of a medicament for the treatment of cancer. Background Art

[0003] Cancer cells have developed several mechanisms to evade host immune surveillance, including: 1) overexpressing the membrane protein CD24, which binds to receptors like Siglec-10 on the surface of immune cells, thereby inhibiting immune activation and escaping immune surveillance by macrophages, T lymphocytes, B lymphocytes, and natural killer cells; and 2) overexpressing the membrane proteins PD-L1 and PD-L2, which bind to PD-1 on the surface of immune cells such as T cells, triggering apoptosis and thereby evading immune surveillance. It can be seen that cancer cells are quite clever, able to rapidly proliferate based on the evasion mechanisms they have developed.

[0004] CD24 and Siglec-10

[0005] Sialic acid-binding immunoglobulin-like lectin (Siglec) is an immunoglobulin-like type I transmembrane protein. Within the Siglec family, Siglec-10 is an inhibitory receptor widely expressed on immune cells such as macrophages, B cells, NK cells, and activated T cells. It has five extracellular Ig-like domains, a transmembrane region, and a cytoplasmic tail. The IgV domain of Siglec-10 contains a key arginine residue that is involved in the recognition of sialic acid. Siglec-10 expression on T cells is known to interfere with T cell activation by inhibiting the formation of T cell major histocompatibility complex class I (MHC-I) peptide complexes and the phosphorylation of the T cell receptor-associated kinases Lck and ZAP-70. Siglec-10 expressed on B cells and NK cells can inhibit BCR-mediated and NK cell receptor-mediated signal transduction (Yin, et al., (2020) Front Immunol 11:1324).

[0006] CD24 is a glycosyl-phosphatidylinositol-anchored protein present on the surface of developing T lymphocytes and most B lymphocytes (Yin et al., supra). Many cancer cells, including ovarian cancer, breast cancer, cervical cancer, endometrial cancer, colon cancer, non-small cell lung cancer, small cell lung cancer, head and neck tumors, urothelial carcinoma, acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), multiple myeloma, Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), bile duct cancer, liver cancer, bladder cancer, pancreatic cancer, gastric cancer and glioblastoma, also highly express CD24 (Barkal et al., (2019) Nature 572(7769):392-396; Liu et al., (2013) Oncol Lett 6(1):96-100; Panagiotou E et al., (2022) J Pers Med. 12(8):1235). CD24 on cancer cells interacts with Siglec-10 on immune cells to generate a "don't eat me" signal for immune evasion and protection of tumor cells from immune attack, including inhibiting the phagocytosis of macrophages.

[0007] Studies have shown that CD24 expression is associated with bladder tumor recurrence (Liu et al., supra). In ovarian cancer patients, CD24 expression is an independent predictor of overall survival and is associated with tumor stage, peritoneal and lymph node metastasis; CD24-positive cells have enhanced proliferation, a highly invasive phenotype, and are associated with cisplatin resistance in ovarian cancer cells (Nakamura et al., (2017) Oncol Rep. 37(6): 3189-3200). CD24 monoclonal antibodies can reduce lung metastasis and prolong overall survival in mouse models of bladder cancer and triple-negative breast cancer. Literature also shows that blocking the CD24-Siglec 10 interaction through antibodies can reduce tumor growth through macrophages and prolong the survival of tumor-bearing mice (Barkal, et al., supra; Chan et al., (2019) Mol Cancer Ther 18(1):147-161; Overdevest et al., (2011) Cancer Res 71(11):3802-11). In addition, in various preclinical animal experiments, CD24 inhibitors have inhibitory effects on the following tumor models: ovarian cancer, breast cancer, non-small cell lung cancer, small cell lung cancer, head and neck cancer, urothelial carcinoma, non-Hodgkin lymphoma (NHL), liver cancer, bladder cancer, pancreatic cancer, gastric cancer and colon cancer (Panagiotou E et al., (2022) J Pers Med. 12(8):1235).

[0008] PD-L1 and PD-1

[0009] PD-1 is a checkpoint molecule that downregulates immune responses and is primarily expressed in activated T and B cells. PD-L1 and PD-L2 are two ligands of PD-1, with PD-L1 expressed on antigen-presenting cells, T cells, B cells, monocytes, and epithelial cells (Keir ME et al., (2008) Annu Rev Immunol. 26:677-704; Chen J et al., (2016) Ann Oncol. 27(3):409-416). The binding of PD-L1 or PD-L2 to PD-1 transmits inhibitory signals, hindering the activation of T and B cells, achieving homeostasis of the immune system, and avoiding accidental damage to normal cells.

[0010] However, the PD-1 pathway can be exploited by tumor cells and other cells to help them evade immune surveillance. Studies have shown that many tumor cells constitutively express PD-L1 and / or PD-L2, and that the tumor microenvironment (TME) induces immune cells, such as infiltrating T cells, to overexpress PD-1 molecules. In this scenario, the PD-1 pathway in the tumor microenvironment is continuously activated, inhibiting T cells from killing tumor cells.

[0011] Studies have shown that blocking the PD-1 pathway can inhibit the growth of a variety of solid tumors and hematological tumors. PD-1 or PD-L1 targeted indications that have been approved or are in clinical trials include melanoma, non-small cell lung cancer, renal cell carcinoma, Hodgkin lymphoma, bladder cancer, head and neck cancer, neuroendocrine cancer, and solid tumors with high microsatellite instability and mismatch repair deficiency, as well as mantle cell lymphoma, diffuse large B-cell lymphoma, and follicular lymphoma (Akinleye A, Rasool Z. (2019) J Hematol Oncol. 12(1):92; Chong Sun et al. (2018) Immunity 48(3):434-452). Currently available PD-1 antibodies include tislelizumab, nivolumab (Opdivo), or pembrolizumab (Keytruda), and approved PD-L1 antibodies include atezolizumab, durvalumab, and avelumab.

[0012] Combination therapy

[0013] Single-target therapies, such as those targeting PD-1 or PD-L1, have shown efficacy in various cancers, but a large proportion of patients do not respond. For example, a review article mentioned that PD-1 or PD-L1 blocking antibodies have limited efficacy in ovarian and pancreatic cancers (Panagiotou E et al., (2022) supra), while CD24 is highly expressed in ovarian and pancreatic cancers (Barkal et al., (2019) Nature 572(7769):392-396; Liu et al., (2013) Oncol Lett 6(1):96-100).

[0014] Drug combination has become a new treatment strategy. When targeting more than one signaling pathway, it is possible to better kill cancer cells and inhibit cancer growth. However, not all drug combinations can achieve better therapeutic effects, and not all drugs can be used in combination. For example, in a centralized analysis of 14 phase I-III studies, it was found that patients receiving dual therapy with PD-1 antibodies and CTLA4 antibodies had a 93% incidence of adverse reactions, while 64% of patients receiving multiple doses of CTLA-4 antibodies experienced immune-related adverse reactions (Wolchok, J.D. et al., (2013) N. Engl. J. Med. 369: 122-33). For example, the combination of panobinostat and carfilzomib caused treatment-related heart failure (2%) in patients with relapsed / refractory multiple myeloma, and the treatment-related mortality rate increased by 2% (Berdeja JG et al., (2015) Haematologica 100 (5): 670-676).

[0015] In addition, to date, the relationship and role of the two immune checkpoint pathways, CD24 / Siglec-10 and PD-1 / PD-L1, are still unclear. Whether the combination of antagonists of the CD24 / Siglec-10 and PD-1 / PD-L1 axes has an anti-cancer effect requires more data support (Panagiotou E et al., (2022) ibid.). Interestingly, in non-small cell lung cancer with low PD-L1 expression, the tumor positivity rate of CD24 seems to be negatively correlated with the non-progression survival rate of patients treated with immune checkpoint inhibitors (Ozawa Y, et al., (2021) Cancer Sci. 112(1):72-80).

[0016] The citation of any document in this application does not constitute an admission that these documents are prior art to this application.

[0017] Summary of the Invention

[0018] The inventors of the present application surprisingly discovered that when the CD24 pathway and the PD-1-PD-L1 pathway are simultaneously targeted, for example, when an antibody that specifically binds to CD24 and an antagonistic PD-1 or PD-L1 antibody are used in combination, the growth of tumors or cancers can be inhibited in a synergistic manner.

[0019] In a first aspect, the present application provides a method for treating cancer, comprising administering to a subject i) an antibody or an antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or an antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction.

[0020] The antibody or antigen-binding portion thereof that specifically binds to CD24 can specifically bind to CD24 (e.g., human CD24) and preferably can block CD24-Siglec binding or CD24-Siglec interaction. In some embodiments, the antibody or antigen-binding portion thereof that specifically binds to CD24 can comprise a heavy chain constant region that binds to FcR to induce CD24. + Antibody-dependent cell-mediated cytotoxicity (ADCC) of tumor cells.

[0021] In some embodiments, the antibody or antigen-binding portion thereof that specifically binds to CD24 may comprise a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region may comprise a heavy chain variable region CDR1 (HV-CDR1), HV-CDR2, and HV-CDR3, and the light chain variable region may comprise a light chain variable region CDR1 (LV-CDR1), LV-CDR2, and LV-CDR3, wherein HV-CDR1, HV-CDR2, and HV-CDR3 may comprise the amino acids GYSITSGYS (SEQ ID NO: 1), IHYSGST (SEQ ID NO: 2), and ARGADYALDY (SEQ ID NO: 3), respectively. NO:3) having at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% sequence identity, LV-CDR1, LV-CDR2, and LV-CDR3 may comprise an amino acid sequence having at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% sequence identity to QSLLYSSNQKNY (SEQ ID NO:4), WAS, and QQNFIYPLT (SEQ ID NO:5), respectively. In some embodiments, the heavy chain variable region and the light chain variable region can comprise an amino acid sequence having at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to 1) SEQ ID NOs: 6 and 7; 2) SEQ ID NOs: 6 and 10; or 3) SEQ ID NOs: 11 and 12. In one embodiment, the heavy chain variable region and the light chain variable region can comprise an amino acid sequence having at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to SEQ ID NOs: 6 and 7, respectively. The antibody or antigen-binding portion thereof that specifically binds to CD24 may further comprise a heavy chain constant region and / or a light chain constant region. The heavy chain constant region may have FcR binding ability, for example, to induce ADCC. In one embodiment, the heavy chain constant region may be, for example, a human IgG1 heavy chain constant region, comprising, for example, the amino acid sequence set forth in SEQ ID NO: 8. The light chain constant region may be, for example, a human kappa light chain constant region, comprising, for example, the amino acid sequence set forth in SEQ ID NO: 9.

[0022] The antibody or antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction can be an antagonist PD-1 antibody or antigen-binding portion thereof that can specifically bind to PD-1, or an antagonist PD-L1 antibody or antigen-binding portion thereof that can specifically bind to PD-L1.

[0023] Antagonist PD-1 antibodies or antigen-binding portions thereof can specifically bind to PD-1 (e.g., human PD-1) and preferably block PD-1-PD-L1 binding or interaction, or PD-1-PD-L1 and PD-1-PD-L2 binding or interaction. In certain embodiments, the antagonist PD-1 antibody or antigen-binding portion thereof can be Tislelizumab, Nivolumab, for example ), Pembrolizumab (e.g. ), or an antigen-binding portion thereof.

[0024] Antagonist PD-L1 antibodies or antigen-binding portions thereof can specifically bind to PD-L1 (e.g., human PD-L1) and preferably block PD-1-PD-L1 binding or PD-1-PD-L1 interaction. In certain embodiments, antagonist PD-L1 antibodies or antigen-binding portions thereof can comprise a heavy chain constant region capable of binding to FcR, for example, to induce inhibition of PD-L1. + ADCC of tumor cells. The antagonist PD-L1 antibody or its antigen-binding portion can be atezolizumab (e.g. ), Durvalumab, Avelumab, IMM2515H, or an antigen-binding portion thereof.

[0025] IMM2515H may comprise a heavy chain variable region and a light chain variable region, wherein the heavy chain variable region may comprise a heavy chain variable region CDR1 (HV-CDR1), HV-CDR2, and HV-CDR3, and the light chain variable region may comprise a light chain variable region CDR1 (LV-CDR1), LV-CDR2, and LV-CDR3, wherein HV-CDR1, HV-CDR2, and HV-CDR3 may comprise GYTFTSNW (SEQ ID NO: 13), IHPNSGSS (SEQ ID NO: 14), and ARSYYGSSPYYFDY (SEQ ID NO: 15), respectively. NO:15) having at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% sequence identity, LV-CDR1, LV-CDR2, and LV-CDR3 can comprise an amino acid sequence having at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99% or 100% sequence identity to QDIINY (SEQ ID NO:16), YTS, and QQGDTLPWT (SEQ ID NO:17), respectively. In some embodiments, the heavy chain variable region and the light chain variable region can comprise an amino acid sequence having at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to SEQ ID NOs: 18 and 19, respectively. IMM2515H can also comprise a heavy chain constant region and / or a light chain constant region. The heavy chain constant region can have FcR binding ability, elicit ADCC, for example. In one embodiment, the heavy chain constant region can be, for example, a human IgG1 heavy chain constant region, comprising, for example, the amino acid sequence set forth in SEQ ID NO: 8. The light chain constant region can be a human kappa light chain constant region, comprising, for example, the amino acid sequence set forth in SEQ ID NO: 9.

[0026] The method may comprise simultaneously administering i) an antibody or an antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or an antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction, or sequentially administering i) an antibody or an antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or an antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction.

[0027] In some embodiments, the cancer may be a solid cancer or a blood cancer, including, but not limited to, gastric cancer, liver cancer, colon cancer, non-small cell lung cancer, small cell lung cancer, ovarian cancer, pancreatic cancer, breast cancer, cervical cancer, endometrial cancer, colon cancer, head and neck cancer, urothelial cancer, bile duct cancer, bladder cancer, glioblastoma, acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), multiple myeloma, Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). In some embodiments, the cancer may be a cancer that expresses CD24. In some embodiments, the cancer may be a cancer that does not express CD24. In some embodiments, the cancer may be a cancer that expresses PD-L1 and / or PD-L2. In some embodiments, the cancer may be a cancer that does not express PD-L1 or PD-L2. In some embodiments, the cancer may be a cancer that highly expresses PD-L1. In some embodiments, the cancer may be a cancer that lowly expresses PD-L1. In some embodiments, the cancer may be colon cancer.

[0028] The present application also relates to the use of i) an antibody or an antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or an antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction in cancer treatment, as well as the use of the antibody or the antigen-binding portion thereof in the preparation of a medicament for cancer treatment.

[0029] In a second aspect, the present application provides a composition, such as a pharmaceutical composition, comprising i) an antibody or an antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or an antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction.

[0030] The definitions of the antibody or antigen-binding portion thereof that specifically binds to CD24 and the antibody or antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction are as described above.

[0031] In one embodiment, a pharmaceutical composition is provided, comprising a therapeutically effective amount of i) an antibody or antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction. The pharmaceutical composition may further comprise a pharmaceutically acceptable carrier.

[0032] In a third aspect, the present application provides a method for treating cancer in a subject in need thereof, comprising administering to the subject i) an antibody or antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction. In some embodiments, the method comprises administering to the subject a composition of the present application.

[0033] Cancer can be a solid cancer or a blood cancer, including, but not limited to, gastric cancer, liver cancer, colon cancer, non-small cell lung cancer, small cell lung cancer, ovarian cancer, pancreatic cancer, breast cancer, cervical cancer, endometrial cancer, head and neck tumors, urothelial cancer, bile duct cancer, bladder cancer, glioblastoma, acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), multiple myeloma, Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL). In some embodiments, the cancer can be a cancer that expresses CD24, PD-L1 and / or PD-L2, or a cancer that does not express CD24, PD-L1, or PD-L2. In some embodiments, the cancer can be a cancer that highly expresses PD-L1. In some embodiments, the cancer can be a cancer that lowly expresses PD-L1. In some embodiments, the cancer can be colon cancer.

[0034] The present application also relates to the use of the composition of the present application in cancer treatment, and the use of the composition in preparing a drug for cancer treatment.

[0035] Based on the following detailed description and examples, other features and advantages of the present disclosure will be very clear, and the detailed description and examples should not be interpreted as being restrictive. All documents, Genbank registration numbers, patents and published patent applications cited in the specification are incorporated herein by reference. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The detailed description given below is given by way of example but is not intended to limit the present application to the specific embodiments described, and can be better understood in conjunction with the accompanying drawings.

[0037] FIG1 shows the changes in the average tumor volume of mice in each group after treatment with IMM47 combined with tislelizumab.

[0038] FIG2 shows the changes in individual tumor volume of mice in each group after treatment with IMM47 combined with tislelizumab.

[0039] Figure 3 shows the IMM47 joint or The average tumor volume changes of mice in each group after treatment.

[0040] Figure 4 shows the IMM47 joint or Changes in individual tumor volume of mice in each group after treatment. DETAILED DESCRIPTION

[0041] Before disclosing and describing the specific embodiments of the present application, it should be understood that the present invention is not limited to the specific methods and materials disclosed herein, which may vary to a certain extent. It should be understood that the terminology used herein is for the purpose of describing specific embodiments only and is not restrictive, as the scope of the present application will be limited only by the appended claims and their equivalents.

[0042] The term "antibody" as used herein includes whole antibodies such as IgG, IgA, IgD, IgE, and IgM, and any antigen-binding fragment (or antigen-binding portion) or single chain thereof. Whole antibodies are glycoproteins comprising at least two heavy chains and two light chains, the heavy chains and light chains being connected by disulfide bonds. Each heavy chain comprises a heavy chain variable region (V H ) and heavy chain constant region. The heavy chain constant region contains three domains, C H1 、C H2 and C H3 Each light chain comprises a light chain variable region (V L ) and the light chain constant region. The light chain constant region comprises a domain C L . V H and V L The V region can be further divided into highly variable regions, namely CDR regions, with relatively conserved framework regions (FR) distributed between the CDR regions. H and V L It is composed of three CDRs and four FR regions, arranged from amino terminus to carboxyl terminus in the order FR1, CDR1, FR2, CDR2, FR3, CDR3, and FR4. The variable regions of the heavy and light chains contain the binding domain that reacts with the antigen. The constant region of an antibody can mediate the binding of the immune protein to host tissues or factors, including various immune system cells (such as effector cells) and the first component of the complement system (C1q).

[0043] The "antigen-binding portion" of an antibody (or simply "antibody portion") refers to one or more fragments of an antibody that retain the ability to specifically bind to an antigen. It has been shown that the antigen-binding function of an antibody can be performed by fragments of a full-length antibody. Examples of binding fragments encompassed by the term "antigen-binding portion" of an antibody include (i) Fab fragments, which consist of V L 、V H 、C L and C H1 (ii) F(ab')2 fragment, a bivalent fragment consisting of two Fab fragments connected by a disulfide bond in the hinge region; (iii) H and C H1Fd fragment composed of a structural domain; (iv) an antibody single-arm V L and V H Fv fragment composed of V H domains (Ward et al., (1989) Nature 341: 544-546); and (vi) separate complementarity determining regions (CDRs). In addition, although the two domains of the Fv fragment, V L and V H , encoded by different genes, which can be connected by a synthetic linker through a recombinant method, wherein the synthetic linker allows them to be prepared as a single protein chain, wherein V L and V H The fragments are paired to form monovalent molecules (called single-chain Fv (scFv)). Such single-chain antibodies are also intended to be included in the term "antigen-binding portion" of an antibody. These antibody fragments are obtained by common techniques known to those skilled in the art, and the fragments are screened for applications in the same manner as intact antibodies.

[0044] The heavy chain variable region CDRs and light chain variable region CDRs of the antibodies or antigen-binding fragments thereof of the present application are identified by the IMGT numbering system. As is well known in the art, heavy chain variable region and light chain variable region CDRs can be identified by, for example, the Chothia, Kabat, AbM or Contact numbering systems / methods.

[0045] The terms "mouse-derived" heavy chain / light chain variable regions used in this article refer to variable regions whose framework (FR) and CDR regions are derived from mouse germline immunoglobulin sequences, while "humanized" heavy chain / light chain variable regions refer to variable regions in which protein sequences derived from non-human species are modified to increase similarity to naturally occurring antibody variants in humans.

[0046] The term "antibody or antigen-binding portion thereof capable of blocking PD-1-PD-L1 binding / interaction" refers to any antibody or antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction, thereby blocking or inhibiting the PD-1 signaling pathway, including but not limited to PD-1 antibodies or antigen-binding portions thereof that specifically bind to PD-1 and block the PD-1-PD-L1 interaction, PD-L1 antibodies or antigen-binding portions thereof that specifically bind to PD-L1 and block the PD-1-PD-L1 interaction, PD-L1 antibodies or antigen-binding portions thereof that specifically bind to PD-L1 and kill PD-L1 cells by inducing ADCC and other pathways, thereby achieving the effect of blocking PD-1-PD-L1, etc.

[0047] The term "antagonist" or "blocking" antibody, or antigen-binding portion thereof, refers to an antibody, or antigen-binding portion thereof, that specifically binds to a specific antigen and blocks the signaling pathway initiated by that antigen. For example, an antagonist PD-1 antibody, or antigen-binding portion thereof, refers to an antibody, or antigen-binding portion thereof, that specifically binds to PD-1 and blocks the PD-1 signaling pathway initiated by, for example, PD-L1, or PD-L1 and PD-L2 binding to PD-1. An antagonist PD-L1 antibody, or antigen-binding portion thereof, refers to an antibody, or antigen-binding portion thereof, that specifically binds to PD-L1 and blocks the PD-1 signaling pathway initiated by the PD-1-PD-L1 interaction. This includes PD-L1 antibodies, or antigen-binding portions thereof, that specifically bind to PD-L1 and block the PD-1-PD-L1 interaction, and PD-L1 antibodies, or antigen-binding portions thereof, that specifically bind to PD-L1 and kill PD-L1 cells by inducing ADCC, thereby achieving a PD-1-PD-L1 blocking effect.

[0048] The "high expression" or "low expression" of PD-L1 mentioned in this application can be determined according to standards known in the art or the standards mentioned in Ozawa Y, et al., (2021) Cancer Sci. 112(1):72-80. The cells used to construct the mouse tumor model in the examples are "highly expressed" PD-L1 relative to common PD-L1-expressing tumor cells.

[0049] The terms "antibody-dependent cellular cytotoxicity," "antibody-dependent cell-mediated cytotoxicity," or "ADCC" refer to a cell-mediated immune defense in which immune system effector cells actively lyse target cells, such as cancer cells, that have surface antigens bound by antibodies, such as CD24.

[0050] "Sequence identity" mentioned herein refers to the nucleotide / amino acid percentages in a sequence that are identical to the nucleotide / amino acid residues in the reference sequence after sequence alignment, and if necessary, spaces are introduced in the sequence comparison to reach the maximum sequence identity percentage between the two sequences. Those skilled in the art can, by various methods, for example, use computer software to perform pairwise sequence comparisons or multiple sequence alignments to determine the sequence identity percentages between two or more nucleic acid or amino acid sequences, such computer software being, for example, ClustalOmega, T-coffee, Kalign, and MAFFT.

[0051] The term "subject" includes any human or non-human animal. The term "non-human animal" includes all vertebrates, such as mammals and non-mammals, such as non-human primates, sheep, dogs, cats, cows, horses, chickens, amphibians, and reptiles, although mammals, such as non-human primates, sheep, dogs, cats, cows and horses, are preferred.

[0052] The phrase "pharmaceutically acceptable" is used herein to refer to those compounds, materials, compositions, and / or dosage forms which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, and / or other problems or complications, consistent with a reasonable benefit / risk ratio.

[0053] As used herein, the term "effective amount" refers to the amount of a drug or pharmaceutical agent, such as the antibody or antigen-binding portion thereof or composition of the present application, that elicits a biological or medical response in a tissue, system, animal or human, for example, that a researcher or clinician is seeking. In addition, the term "therapeutically effective amount" refers to any amount that results in improved treatment, cure, prevention, alleviation of a disease, condition or side effect, or a reduction in the rate of progression of a disease or condition, compared to a corresponding subject not receiving such amount. An effective amount can be administered in one or more administrations, applications or dosages and is not intended to be limited to a particular formulation or route of administration. For example, a "therapeutically effective amount" of the composition or antibody combination of the present application preferably results in a reduction in the severity of disease symptoms, an increase in the frequency and duration of disease-free periods, or prevention of damage or disability caused by the disease. For example, for the treatment of tumor-bearing subjects, a "therapeutically effective amount" means that, relative to untreated subjects, tumor growth is preferably inhibited by at least about 40%, more preferably by at least about 60%, more preferably by at least about 80%, and more preferably by at least about 99%.

[0054] As used herein, the term "treat" includes any effect that causes improvement, such as alleviation, reduction, modulation, amelioration or elimination, of a symptom, disease, condition, etc., or ameliorates the symptoms thereof.

[0055] As used herein, the term "pharmaceutical composition" refers to the combination of an active agent and a carrier (inert or active) that renders the composition particularly suitable for diagnostic or therapeutic use in vivo or in vitro.

[0056] Combination therapy

[0057] The present application provides a combination therapy for cancer, comprising administering to a subject i) an antibody or an antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or an antigen-binding portion thereof that can block PD-1-PD-L1 binding or interaction.

[0058] In one embodiment, an antibody or antigen-binding portion thereof that specifically binds to CD24 comprises the amino acid sequences shown in the heavy chain variable region CDR1 (HV-CDR1), HV-CDR2, HV-CDR3, and the light chain variable region CDR1 (LV-CDR1), LV-CDR2, and LV-CDR3, respectively, of GYSITSGYS (SEQ ID NO: 1), IHYSGST (SEQ ID NO: 2), ARGADYALDY (SEQ ID NO: 3), QSLLYSSNQKNY (SEQ ID NO: 4), WAS, and QQNFIYPLT (SEQ ID NO: 5). It may comprise a heavy chain constant region that binds to FcR to elicit binding to CD24. + Antibody-dependent cell-mediated cytotoxicity (ADCC) of tumor cells. Exemplary antibodies IMM47, IMM47C and IMM47H are described in Chinese patent application CN202111195246.5 and have been shown to have CD24 + Cell binding, which can trigger CD24 + It can induce ADCC of cells and has strong anti-tumor activity in vivo.

[0059] An antibody or antigen-binding portion thereof that can block PD-1-PD-L1 binding or interaction refers to any antibody or antigen-binding portion thereof that can block or inhibit the PD-1 signaling pathway, including, but not limited to, a PD-1 antibody or antigen-binding portion thereof that specifically binds to PD-1 and blocks the PD-1-PD-L1 interaction, a PD-L1 antibody that specifically binds to PD-L1 and blocks the PD-1-PD-L1 interaction, and a PD-L1 antibody that specifically binds to PD-L1 and kills PD-L1 cells by inducing ADCC and other pathways, thereby achieving the effect of blocking PD-1-PD-L1.

[0060] It is well known in the field of antibodies that the CDR region is crucial for the antigen binding of an antibody, while the amino acids in the framework region of the variable region can be modified or altered to a certain extent without changing the antigen binding ability and binding specificity of the antibody.

[0061] The combination therapy of the present application can be used to treat cancer, including but not limited to colon cancer. In some embodiments, the combination therapy of the present application shows a synergistic effect, with significantly better tumor killing effect than CD24 targeting alone and PD-1 / PD-L1 targeting alone. Moreover, compared with single-target therapy, the dosage of each antibody can be reduced to a certain extent, and when used in combination, it still shows better therapeutic effect than single-target therapy.

[0062] The combination therapy of the present application can be applied to animals, preferably mammals (e.g., domestic animals, cats, dogs, mice, rats), and more preferably humans. Any method of administration can be used to administer the two antibodies in this application to a subject in need. In certain embodiments, the two antibodies used in combination in this application are administered parenterally, for example, by intraperitoneal injection, intravenous injection, etc.

[0063] One or more other agents or treatment methods such as other chemotherapeutic agents or other anticancer agents, immunopotentiators, immunosuppressants, antitumor vaccines, and / or cytokine therapies (e.g., IL2 and GM-CSF) can optionally be used in combination with the combination therapy of the present application. Other agents can be combined with the two antibodies of the present application in a single dosage form, or these therapeutic agents can be used as separate dosage forms.

[0064] The combination therapy of the present application can be administered simultaneously as a single composition in a pharmaceutically acceptable carrier, or as separate compositions in which each drug is in a pharmaceutically acceptable carrier. If more than one dose of the combination therapy is to be administered sequentially, the order of sequential administration can be reversed or maintained in the same order at each administration time point. Sequential administration can be combined with simultaneous administration, or any combination thereof.

[0065] Composition and application

[0066] The present application provides a pharmaceutically acceptable composition comprising a therapeutically effective amount of an antibody or antigen-binding portion thereof that specifically binds to CD24, formulated together with one or more pharmaceutically acceptable carriers, a therapeutically effective amount of an antibody or antigen-binding portion thereof that can block PD-1-PD-L1 binding or interaction, formulated together with one or more pharmaceutically acceptable carriers, and optionally, one or more other desired therapeutic agents.

[0067] Pharmaceutical compositions may contain any number of carriers, including surfactants, thickening or emulsifying agents, solid binders, dispersing or suspending agents, solubilizing agents, coloring agents, flavoring agents, coatings, disintegrants, lubricants, sweeteners, preservatives, isotonic agents, and combinations thereof.

[0068] Preferably, pharmaceutical composition is suitable for intravenous, intramuscular, subcutaneous, parenteral, spinal column or epidermal administration (for example, by injection or infusion).Based on the difference of route of administration, effective ingredient can be wrapped in material, to protect it from the impact of acid and other natural conditions that may make its inactivation.Term used herein " parenteral administration " refers to the administration mode of administration of non-enteral and non-local external use, is usually carried out by injection, includes but not limited to intravenous, intramuscular, intraarterial, intrathecal, intracapsular, intraorbital, intracardiac, intradermal, intraperitoneal, through trachea, subcutaneous, subcutaneous, intraarticular, subcapsular, subarachnoid space, intraspinal canal, epidural and intrasternal injection and infusion.Or, the composition of the application can be administered by non-parenteral approach, for example external, epidermal or mucosal administration, for example intranasal, oral, vaginal, rectal, sublingual, or local external use.

[0069] Pharmaceutical compositions can be in the form of sterile aqueous solutions or dispersions. They can also be formulated in microemulsions, liposomes, or other ordered structures suitable for high drug concentration.

[0070] The dosage regimen of the pharmaceutical compositions of the present application will vary based on known factors, such as the pharmacodynamic properties of each specific drug, its mode of administration and route of administration; the species, age, sex, health status, disease state, and weight of the recipient; the nature and extent of symptoms; the type of concurrent treatment; the frequency of treatment; the route of administration, the patient's renal and liver function, and the desired effect. The amount of active ingredient that can be prepared in a single dosage form with the carrier material will vary depending on the subject being treated and the specific mode of administration, and is generally the amount of the composition that produces a therapeutic effect. Basically, in terms of percentage, this amount is about 0.01% to about 99% of the active ingredient combined with a pharmaceutically acceptable carrier.

[0071] The dosage regimen can be adjusted to provide the optimal desired response (e.g., a therapeutic response). For example, a bolus can be administered, multiple divided doses can be administered over time, or the dose can be reduced or increased in proportion to the severity of the therapeutic situation. It is particularly advantageous to configure the parenteral composition in a dosage unit format for ease of administration and uniformity of dosage. As used herein, a dosage unit format refers to a physically discrete unit suitable for a single administration to a subject; each unit contains a predetermined amount of the active ingredient calculated to produce the desired therapeutic effect together with the required pharmaceutical carrier. Alternatively, the antibody can be administered as a sustained-release formulation, in which case the required dosing frequency is reduced. Controlled-release dosage forms include implants, transdermal patches, and microencapsulated delivery systems. Biodegradable, biocompatible polymers such as ethylene vinyl acetate, polyanhydrides, polyglycolic acid, collagen, polyorthoesters, and polylactic acid can be used. In certain embodiments, the compositions of the present application can be formulated to ensure proper distribution in the body. For example, to ensure that the compositions of the present application can cross the blood-brain barrier, they can be formulated in liposomes.

[0072] The application also relates to in vivo gene therapy, in which nucleic acid molecules encoding two antibodies or antigen-binding portions thereof of the present application are directly introduced into a subject. For example, the nucleic acid sequence encoding the present antibody or antigen-binding portion thereof is introduced into the target cell via a nucleic acid construct with or without a suitable delivery vector such as an adeno-associated viral vector through local injection. Other alternative viral vectors include but are not limited to retroviruses, adenoviruses, herpes simplex viruses, and papillomavirus vectors. The in vivo physical transfer of viral vectors can be achieved by local injection of the desired nucleic acid construct or other suitable delivery vectors comprising the desired nucleic acid sequence, liposome-mediated transfer, direct injection (naked DNA), or microparticle bombardment (gene gun).

[0073] The composition of the present application can be used to treat cancer, including but not limited to colon cancer. In some embodiments, the administration of the composition of the present application shows a synergistic effect, with significantly better tumor killing effect than CD24 targeting alone and PD-1 / PD-L1 targeting alone.

[0074] The present application will be further described with reference to the following non-limiting examples.

[0075] Example

[0076] IMM47 in the present application is an IgG antibody targeting CD24, comprising two heavy chains and two light chains, wherein each heavy chain comprises a mouse heavy chain variable region (SEQ ID NO: 6) and a human IgG1 constant region (SEQ ID NO: 8), and each light chain comprises a humanized light chain variable region (SEQ ID NO: 7) and a human κ constant region (SEQ ID NO: 9).

[0077] IMM47 and two other CD24 antibodies, IMM47C and IMM47H, which have the same heavy and light chain variable region CDRs, have been shown to have CD24 + Cell binding, which can trigger CD24 + The IMM47C antibody, which contains a mouse heavy chain variable region (SEQ ID NO: 6), a human IgG1 constant region (SEQ ID NO: 8), a mouse light chain variable region (SEQ ID NO: 10), and a human kappa constant region (SEQ ID NO: 9), is a potent in vivo anti-tumor agent. IMM47H, on the other hand, contains a humanized heavy chain variable region (SEQ ID NO: 11), a human IgG1 constant region (SEQ ID NO: 8), a humanized light chain variable region (SEQ ID NO: 12), and a human kappa constant region (SEQ ID NO: 9). For details, see Chinese patent application CN202111195246.5.

[0078] IMM2515H in this application is an IgG antibody targeting PD-L1, comprising two heavy chains and two light chains, wherein each heavy chain comprises a heavy chain variable region (SEQ ID NO: 18) and a human IgG1 constant region (SEQ ID NO: 8), and each light chain comprises a light chain variable region (SEQ ID NO: 19) and a human κ constant region (SEQ ID NO: 9).

[0079] Example 1. In vivo anti-tumor efficacy of IMM47 combined with tislelizumab

[0080] The human CD24 gene (Uniprot ID#P25063) was cloned into the neomycin-resistant expression vector pMac-G418 using the HindШ and NotI restriction sites to generate the hCD24 expression plasmid. Furthermore, the human PD-L1 gene (Uniprot ID#Q9NZQ7) was cloned into the puromycin-resistant expression vector pMac-Pur using the HindШ and NotI restriction sites to generate the hPD-L1 expression plasmid.

[0081] MC38 cells were transiently transfected with the hCD24 expression plasmid using PEI reagent, and polyclones stably expressing human CD24 were obtained by neomycin pressure selection. Subcloning was performed in 96-well plates using limiting dilution to select stable, high-expressing monoclonal cell lines. Using the same procedure, the selected MC38 cells stably and highly expressing human CD24 were transfected with the hPD-L1 expression plasmid. Monoclonal cell lines that stably and highly expressed both human CD24 and human PD-L1 were selected using puromycin.

[0082] The MC38-hCD24 / hPD-L1 cells prepared as above were cultured in high-glucose DMEM medium containing 10% inactivated fetal bovine serum in an incubator at 37°C and 5% CO2. The cells were passaged every 2 to 3 days when the confluence reached 80%.

[0083] MC38-hCD24 / hPD-L1 cells in the logarithmic growth phase were taken and resuspended in PBS. The cells were counted and the cell concentration was adjusted to 3.0×10 7 The cell suspension was inoculated subcutaneously in the right flank of 6-8 week old C57BL / 6-hPD-1 mice using a 1 mL syringe, 100 μL per mouse, and approximately 3.0 × 10 6 cells.

[0084] When the average tumor volume reached about 89 mm 3At the same time, mice with moderate tumor volume were selected and enrolled. The animals were randomly divided into experimental groups according to the tumor volume, with 6 mice in each group. The day of grouping was defined as D0, and the drugs were administered by intraperitoneal injection (ip). The specific dosing schedule is shown in Table 1.

[0085] Table 1. Dosage regimen

[0086] Tumor volume was measured twice a week until D33. The volume of tumor in the solvent group was larger than 3000 mm on D26. 3 The mice were euthanized. Tumor volume (TV) was calculated as TV = 1 / 2 × a × b 2 Calculate, where a represents the long diameter of the tumor and b represents the short diameter of the tumor.

[0087] Relative tumor volume (RTV) is expressed as RTV = Vt / V 初始 × 100% calculation, where V 初始 V is the tumor volume measured at the time of group administration (i.e. D0), t The relative tumor growth rate T / C (%) was calculated as T / C (%) = (T RTV / C RTV )×100%, where T RTV represents the relative tumor volume of the treatment group, C RTV The tumor volume inhibition rate (TGI) was calculated as TGI = [1-(TV t -TV 初 始 ) / (CV t -CV 初始 )]×100%, of which TV t represents the tumor volume of the treatment group at each measurement, TV 初始 represents the tumor volume of the treatment group at the time of drug administration, CV t represents the tumor volume of the control group at each measurement, CV 初始 The body weight change rate (BWC) of animals was calculated as (BW 最终 -BW 最 初 ) / BW 最初 × 100%, where BW 最初 Indicates the weight of animals when they were grouped and dosed, BW 最终 Indicates the weight of the animals at each measurement. The tumor weight inhibition rate (IR) was calculated as (W C -W T ) / W C × 100%, where W C represents the tumor weight of the control group, W TThe raw data were measured and recorded, and the analysis and processing were performed based on the raw data. The results were expressed as mean ± SEM. The difference in tumor volume between the control group and the treatment group was analyzed using T test. P < 0.05 indicated the presence of a statistically significant difference.

[0088] Figure 1 shows that tislelizumab has a moderate anti-tumor effect, with the greatest efficacy seen with IMM47 alone and the combination of IMM47 and tislelizumab. Figure 2 shows changes in tumor volume in individual mice, demonstrating that the combination of IMM47 and tislelizumab exhibited superior anti-tumor efficacy compared to IMM47 alone. Specifically, the complete remission (CR) rate reached 100% with the IMM47 + tislelizumab combination, while it was slightly lower with IMM47 alone.

[0089] It can be seen that IMM47 and tislelizumab act on tumors, such as colon cancer, in a synergistic manner, resulting in the complete killing of tumor cells.

[0090] Example 2. IMM47 and or In vivo anti-tumor efficacy of the combination

[0091] MC38-hCD24 / hPD-L1 cells were cultured in high-glucose DMEM medium containing 10% inactivated fetal bovine serum in an incubator at 37°C and 5% CO2. The cells were passaged every 2 to 3 days when the confluence reached 80%.

[0092] MC38-hCD24 / hPD-L1 cells in the logarithmic growth phase were taken and resuspended in PBS. The cells were counted and the cell concentration was adjusted to 3.0×10 7 The cell suspension was inoculated subcutaneously in the right flank of 6-8 week old C57BL / 6-hPD-1 mice using a 1 mL syringe, 100 μL per mouse, and approximately 3.0 × 10 6 cells.

[0093] When the average tumor volume reaches about 90 mm 3 At the same time, mice with moderate tumor volume were selected and enrolled. The animals were randomly divided into experimental groups according to the tumor volume, with 6 mice in each group. The day of grouping was defined as D0, and the drugs were administered by intraperitoneal injection (ip). The specific dosing schedule is shown in Table 2.

[0094] Table 2. Dosage regimen

[0095] Tumor volume was measured twice a week until D24. Tumor volume (TV) was calculated using TV = 1 / 2 × a × b 2 Calculate, where a represents the long diameter of the tumor and b represents the short diameter of the tumor.

[0096] Relative tumor volume (RTV), relative tumor growth rate (T / C) (%), tumor volume inhibition rate (TGI), animal body weight change rate (BWC), and tumor weight inhibition rate (IR) were calculated as described above. Raw data were measured and recorded, and analysis and processing were performed based on the raw data. The results were expressed as mean and standard error (mean ± SEM). T-tests were used to analyze the difference in tumor volume between the control group and the treatment group. P < 0.05 indicated a statistically significant difference.

[0097] As can be seen from Figure 3, IMM47 alone, Single administration, and When administered alone, both can effectively inhibit tumor growth, while IMM47+ Combined administration, and IMM47+ Combined administration can completely eliminate tumor tissue. From the changes in individual tumors in Figure 4, it can be further seen that IMM47 and or The complete remission rate (CR) in the combination group was very high, significantly higher than that in other groups, indicating that the combination inhibited tumor growth in a synergistic manner.

[0098] Based on the results of Examples 1 and 2, high-dose IMM47 alone demonstrated strong anti-tumor efficacy, which may have masked its synergistic effect when combined with PD-1 antibodies. However, when the IMM47 dose was reduced, its synergistic effect with PD-1 antibodies became more pronounced. This suggests that the combination of IMM47 and PD-1 antibodies can achieve even better anti-tumor efficacy at a lower dose.

[0099] Example 3. In vivo anti-tumor efficacy of IMM47 combined with PD-L1 antibody

[0100] Further testing of IMM47 and PD-L1 antibodies, In vivo antitumor efficacy of atezolizumab or IMM2515H in combination.

[0101] MC38-hCD24 / hPD-L1 cells were cultured in high-glucose DMEM medium containing 10% inactivated fetal bovine serum in a 37°C, 5% CO2 incubator. The cells were passaged every 2 to 3 days when the confluence reached 80%.

[0102] MC38-hCD24 / hPD-L1 cells in the logarithmic growth phase were taken and resuspended in PBS. The cells were counted and the cell concentration was adjusted to 3.0×10 7 The cell suspension was inoculated subcutaneously in the right flank of 6-8 week old C57BL / 6-hPD-1 mice using a 1 mL syringe, 100 μL per mouse, and approximately 3.0 × 106 cells.

[0103] When the average tumor volume reaches about 100 mm 3 At the same time, mice with moderate tumor volume were selected and enrolled. The animals were randomly divided into experimental groups according to the tumor volume, with 6 mice in each group. The day of grouping was defined as D0, and the drugs were administered by intraperitoneal injection (ip). The specific dosing schedule is shown in Table 3.

[0104] Table 3. Dosage regimen

[0105] Tumor volume was measured twice a week until D24. Tumor volume (TV) was calculated using TV = 1 / 2 × a × b 2 Calculate, where a represents the long diameter of the tumor and b represents the short diameter of the tumor.

[0106] Relative tumor volume (RTV), relative tumor growth rate (T / C) (%), tumor volume inhibition rate (TGI), animal body weight change rate (BWC), and tumor weight inhibition rate (IR) were calculated as described above. Raw data were measured and recorded, and analysis and processing were performed based on the raw data. The results were expressed as mean and standard error (mean ± SEM). T-tests were used to analyze the difference in tumor volume between the control group and the treatment group. P < 0.05 indicated a statistically significant difference.

[0107] The sequence information of this application is summarized below.

[0108] Although the present application has been described in conjunction with one or more embodiments, it should be understood that the present application is not limited to these embodiments. The description in this application is intended to cover all variants and equivalents, all of which are included in the subject matter and scope of the appended claims. All documents cited in this article are incorporated herein by reference in their entirety.

Claims

1. A composition comprising: i) an antibody or antigen-binding portion thereof that specifically binds to CD24, and ii) an antibody or antigen-binding portion thereof that is capable of blocking PD-1-PD-L1 binding or PD-1-PD-L1 interaction, in, The antibody or antigen-binding portion thereof that specifically binds to CD24 comprises a heavy chain variable region and a light chain variable region, the heavy chain variable region comprising HV-CDR1, HV-CDR2, and HV-CDR3, and the light chain variable region comprising LV-CDR1, LV-CDR2, and LV-CDR3, wherein HV-CDR1, HV-CDR2, HV-CDR3, LV-CDR1, LV-CDR2, and LV-CDR3 respectively comprise the amino acid sequences of GYSITSGYS (SEQ ID NO: 1), IHYSGST (SEQ ID NO: 2), ARGADYALDY (SEQ ID NO: 3), QSLLYSSNQKNY (SEQ ID NO: 4), WAS, and QQNFIYPLT (SEQ ID NO: 5).

2. The composition of claim 1, wherein the heavy chain variable region and light chain variable region of the antibody, or antigen-binding portion thereof, that specifically binds to CD24 comprise the amino acid sequences shown in 1) SEQ ID NOs: 6 and 7; 2) SEQ ID NOs: 6 and 10; or 3) SEQ ID NOs: 11 and 12, respectively.

3. The composition of claim 1, wherein the antibody or antigen-binding portion thereof that specifically binds to CD24 further comprises a heavy chain constant region that has FcR binding ability. The composition of claim 3 , wherein the heavy chain constant region having FcR binding ability is a human IgG1 heavy chain constant region.

5. The composition of claim 1, wherein the antibody or antigen-binding portion thereof that specifically binds to CD24 comprises a heavy chain constant region and a light chain constant region, wherein the heavy chain constant region comprises the amino acid sequence shown in SEQ ID NO: 8, and the light chain constant region comprises the amino acid sequence shown in SEQ ID NO:

9.

6. The composition of claim 1, wherein the antibody or antigen-binding portion thereof capable of blocking PD-1-PD-L1 binding or PD-1-PD-L1 interaction is an antagonist PD-1 antibody or antigen-binding portion thereof that specifically binds to PD-1, or Antagonist PD-L1 antibodies or antigen-binding portions thereof that specifically bind to PD-L1.

7. The composition of claim 6, wherein the antagonist PD-1 antibody is selected from tislelizumab, nivolumab, and pembrolizumab.

8. The composition of claim 6, wherein the antagonist PD-L1 antibody is selected from atezolizumab, and IMM2515H, IMM2515H contains heavy chain variable region and light chain variable region, and the heavy chain variable region includes HV-CDR1, HV-CDR2, and HV-CDR3, the light chain variable region comprises LV-CDR1, LV-CDR2, and LV-CDR3, wherein HV-CDR1, HV-CDR2, HV-CDR3, LV-CDR1, LV-CDR2, and LV-CDR3 respectively comprise the amino acid sequences of GYTFTSNW (SEQ ID NO: 13), IHPNSGSS (SEQ ID NO: 14), ARSYYGSSPYYFDY (SEQ ID NO: 15), QDIINY (SEQ ID NO: 16), YTS, and QQGDTLPWT (SEQ ID NO: 17).

9. An antibody or antigen-binding portion thereof that specifically binds to CD24, and an antibody or antigen-binding portion thereof that can block PD-1-PD-L1 binding or PD-1-PD-L1 interaction, for use in the preparation of a cancer therapeutic drug, wherein the antibody or antigen-binding portion thereof that specifically binds to CD24 comprises a heavy chain variable region and a light chain variable region, the heavy chain variable region comprises HV-CDR1, HV-CDR2, and HV-CDR3, and the light chain variable region comprises LV-CDR1, LV-CDR2, and LV-CDR3, wherein HV-CDR1, HV-CDR2, HV-CDR3, LV-CDR1, LV-CDR2, and LV-CDR3 respectively comprise GYSITSGYS (SEQ ID NO: 1), IHYSGST (SEQ ID NO: 2), ARGADYALDY (SEQ ID NO: 3), QSLLYSSNQKNY (SEQ ID NO: 4), WAS, and QQNFIYPLT (SEQ ID NO: 5). NO:5) amino acid sequence.

10. The use of claim 9, wherein the heavy chain variable region and light chain variable region of the antibody or antigen-binding portion thereof that specifically binds to CD24 comprise the amino acid sequences shown in 1) SEQ ID NOs: 6 and 7; 2) SEQ ID NOs: 6 and 10; or 3) SEQ ID NOs: 11 and 12, respectively.

11. The use according to claim 9, wherein the antibody or antigen-binding portion thereof that specifically binds to CD24 further comprises a heavy chain constant region with FcR binding ability.

12. The use according to claim 9, wherein the antibody or antigen-binding portion thereof that specifically binds to CD24 comprises a heavy chain constant region and a light chain constant region, wherein the heavy chain constant region comprises the amino acid sequence shown in SEQ ID NO: 8, and the light chain constant region comprises the amino acid sequence shown in SEQ ID NO:

9.

13. The use according to claim 9, wherein the antibody or antigen-binding portion thereof capable of blocking PD-1-PD-L1 binding or PD-1-PD-L1 interaction is an antagonist PD-1 antibody or antigen-binding portion thereof that specifically binds to PD-1, or Antagonist PD-L1 antibodies or antigen-binding portions thereof that specifically bind to PD-L1.

14. The composition of claim 13, wherein the antagonist PD-1 antibody is selected from tislelizumab, nivolumab, and pembrolizumab.

15. The composition of claim 13, wherein the antagonist PD-L1 antibody is selected from atezolizumab, and IMM2515H, IMM2515H contains heavy chain variable region and light chain variable region, and the heavy chain variable region includes HV-CDR1, HV-CDR2, and HV-CDR3, the light chain variable region comprises LV-CDR1, LV-CDR2, and LV-CDR3, wherein HV-CDR1, HV-CDR2, HV-CDR3, LV-CDR1, LV-CDR2, and LV-CDR3 respectively comprise the amino acid sequences of GYTFTSNW (SEQ ID NO: 13), IHPNSGSS (SEQ ID NO: 14), ARSYYGSSPYYFDY (SEQ ID NO: 15), QDIINY (SEQ ID NO: 16), YTS, and QQGDTLPWT (SEQ ID NO: 17).

16. The method of claim 9, wherein the cancer is selected from the group consisting of gastric cancer, liver cancer, colon cancer, non-small cell lung cancer, small cell lung cancer, ovarian cancer, pancreatic cancer, breast cancer, cervical cancer, endometrial cancer, head and neck tumors, urothelial carcinoma, bile duct cancer, bladder cancer, glioblastoma, acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), multiple myeloma, Hodgkin lymphoma (HL) and non-Hodgkin lymphoma (NHL).

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