WO2023165602A1

WO2023165602A1 - Combinational use of anti-cd47 antibody

Info

Publication number: WO2023165602A1
Application number: PCT/CN2023/079555
Authority: WO
Inventors: Haiying Zhou; Anthony CAO; Jiaqing YI; Jing Li; Omar Kabbarah
Original assignee: Zai Lab (Us) Llc; Zai Lab (Shanghai) Co., Ltd.
Priority date: 2022-03-04
Filing date: 2023-03-03
Publication date: 2023-09-07

Abstract

Provided is the use of anti-CD47 antibody in combination with another antibody and/or a chemotherapy agent.

Description

COMBINATIONAL USE OF ANTI-CD47 ANTIBODY

FIELD

This application is related to a combinational use involving an anti-CD47 antibody, a Fc-intact antibody, and a chemotherapy agent.

BACKGROUND

CD47, through binding with SIRPα expressed on macrophages and other myeloid cells, acts as a “marker of self” signal to inhibit macrophage phagocytosis. It has an elevated expression in several human cancers including solid tumors such as gastric, esophageal, breast, colon, liver, bladder, brain, ovarian, renal, prostate carcinomas, melanoma, colorectal cancer, and blood cancers such as myelodysplastic syndrome (MDS) , AML, ALL, CLL, CML, DLBCL, FL, MCL, and MM. Indeed, CD47 mechanism of signaling “don’ t eat me” is employed by cancer cells to escape immunological elimination. This has made CD47 a potential therapeutic target for cancer treatment. Anti-CD47 antibody can disrupt the binding of CD47 with SIRPα thereby preventing CD47 from sending signals to evade phagocytosis.

Currently, no anti-CD47 antibody has been approved for marketing. There are on-going clinical investigations into the combinational use of anti-CD47 antibody with azacitidine in previously untreated intermediate, high, and very high-risk MDS.

This application discloses the combinational use of an anti-CD47 antibody with a Fc-intact antibody and a chemotherapy agent.

SUMMARY

Provided is a method of treating cancer in a subject in need thereof, wherein the method comprises administering to the subject an effective amount of (1) an anti-CD47 antibody and (2) a Fc-intact antibody.

Provided is a method of treating cancer in a subject in need thereof, wherein the method comprises administering to the subject an effective amount of (1) an anti-CD47 antibody, (2) a Fc-intact antibody, and (3) a chemotherapy agent.

In some embodiments, the cancer has elevated expression levels of both CD47 and another antigen against which the Fc-intact antibody binds. In some embodiments, the cancer has elevated expression level of CD47 with positive expression of another antigen against which the Fc-intact antibody binds.

In some embodiments, another antigen is therapeutically targeted using monoclonal antibodies with an intact Fc domain. In some embodiments, another antigen is selected from HER2, EGFR, and CD20.

In some embodiments, the anti-CD47 antibody comprises a variable light chain region and a variable heavy chain region, wherein the variable light chain region comprises CDR1 having the sequence of SEQ ID NO: 1, CDR2 having the sequence of SEQ ID NO: 2, and CDR3 having the sequence of SEQ ID NO: 3, the variable heavy chain region comprises CDR1 having the sequence of SEQ ID NO: 4, CDR2 having the sequence of SEQ ID NO: 5, and CDR3 having the sequence of SEQ ID NO: 6.

In some embodiments, the anti-CD47 antibody comprises the sequences of SEQ ID NOs: 7 and 8.

In some embodiments, the Fc-intact antibody is selected from trastuzumab, cetuximab, and rituximab.

In some embodiments, the chemotherapy agent is selected from platinum compound and taxanes. In some embodiments, the chemotherapy agent is selected from cisplatin, carboplatin and oxaliplatin. In some embodiments, the chemotherapy agent is cisplatin. In some embodiments, the chemotherapy agent is selected from paclitaxel and docetaxel.

In some embodiments, the cancer is selected from breast cancer, ovarian cancer, gastric cancer, head and neck squamous cell carcinomas, and lymphoma.

In some embodiments, gastric cancer, breast cancer, and ovarian cancer have elevated expression levels of both CD47 and HER2. In some embodiments, Head and neck squamous cell carcinomas has elevated expression level of CD47, with positive EGFR expression. In some embodiments, lymphoma has elevated expression level of CD47, with positive CD20 expression.

In some embodiments, the method comprises administering anti-CD47 antibody at a dose of 0.1-30 mg/kg once or twice weekly to the subject. In some embodiments, the method comprises administering anti-CD47 antibody at a dose of 0.1, 0.3, 1, 3, 5, 10, 15, 20, 25, or 30 mg/kg once or twice weekly to the subject.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 depicts tumor growth inhibition as a function of days after treatment with anti-

CD47 antibody in combination with trastuzumab and/or docetaxel in HCC1954 breast cancer xenograft model.

FIG. 2 depicts tumor growth inhibition as a function of days after treatment with anti-CD47 antibody in combination with trastuzumab and/or paclitaxel in SK-OV-3 ovarian cancer xenograft model.

FIG. 3 depicts tumor growth inhibition as a function of days after treatment with anti-CD47 antibody in combination with trastuzumab and/or docetaxel in ST-02-0077 gastric cancer patient-derived-xenograft (PDX) model.

FIG. 4 depicts tumor growth inhibition as a function of days after treatment with anti-CD47 antibody in combination with cetuximab and/or cisplatin in FaDu Head and neck squamous cell carcinomas (HNSCC) xenograft model.

FIG. 5 depicts tumor growth inhibition as a function of days after treatment with anti-CD47 antibody in combination with rituximab in Raji lymphoma xenograft model.

FIG. 6A-D depicts anti-CD47 antibody binding to CD47 in a dose dependent manner on cell lines OVCAR-3 (FIG. 6A) , HCC1954 (FIG. 6B) , SK-OV-3 (FIG. 6C) , and Jurkat (FIG. 6D) .

FIG. 7A depicts anti-CD47 antibody blocking CD47/SIRPα interaction through PathHunter SIRPa signaling.

FIG. 7B-D depicts phagocytosis promoted by anti-CD47 antibody in in vitro co-culture system with differentiated macrophages and tumor cells including Toledo (FIG. 7B) , OVCAR-3 (FIG. 7C) , and FaDu (FIG. 7D) .

FIG. 7E and 7F depicts phagocytosis promoted by anti-CD47 antibody in in vitro co-culture system with differentiated macrophages and tumor cells including Toledo (E) and FaDu (F) in a dose-dependent manner.

FIG. 8A depicts surface expression levels of CD47 in various cancer models by flow cytometry analysis. FIG. 8B-E depicts CD47 (FIG. 8B) , HER2 (FIG. 8C) , CD20 ( (FIG. 8D) , and EGFR ( (FIG. 8E) transcript levels in cancer models by RT-qPCR analysis

DETAILED DESCRIPTION

I. Definition

As used herein, the singular forms “a, ” “an, ” and “the” include plural referents unless the context clearly indciates otherwise.

The term “antibody” as used herein refers to a molecule comprising at least a variable light chain region and a variable heavy chain region, wherein the molecule is capable of binding to antigen. Both “Variable light chain region” and “variable heavy chain region” refer to a polypeptide comprising three CDRs. The term “antibody” also includes fragments that are capable of binding to antigen, such as Fv, single-chain Fv (scFv) , Fab, Fab’ , and (Fab’ ) ₂. The antibody can be chimeric antibody, humanized antibody, human antibody, and antibody of various species including mouse and cynomolgus monkey, etc.

The term "CDR" refers to the complementarity determining region within antibody variable sequences. There are three CDRs in each of the variable light chain and heavy chain regions, which are designated CDR1, CDR2 and CDR3, for each of the variable regions.

“Anti-CD47 antibody” refers to an antibody binding to CD47 and examples thereof include those described in PCT/CN2018/074318 (WO 2018/137705) , which are incorporated herein by reference in their entirety and for all purposes.

“Chemotherapy agent” as used herein refers to clinically used small molecule anti-cancer agent.

The term “subject” as used herein refers to animal (such as mammal) or human.

As used herein, a “therapeutically effective amount” refers to the amount that, when administered to a subject for treatment of a disease, is sufficient to cause a desired treatment effect in the subject, including for example, alleviation of the symptoms or stop of the progression of the disease, such as reducing tumor volume.

The terms “treating” , “treatment” , or “treat” (of) a disease refers to slowing or arresting the development of a disease, providing relief from the symptoms or side-effects of the disease, and/or causing regression of the disease. The terms also refer to reduction of the occurrence of the disease in the subject when compared with a subject without the treatment.

The term “Fc-intact antibody” refers to any clinically used monoclonal antibodies that bind to proteins expression on the cell surface of tumor cells and elicit Fc receptor-mediated effector functions (e.g., ADCC, ADCP, CDC) . Exemplary Fc-intact antibody includes trastuzumab, cetuximab, and rituximab.

“Fc-mediated Effector functions” refer to biological functions induced via the Fc region of an antibody, which can vary with the antibody isotype. Effector functions include antibody dependent cell-mediated cytotoxicity (ADCC) , C1q binding and complementary dependent cytotoxicity (CDC) , and antibody dependent cellular phagocytosis (ADCP) . The critical step for ADCC is the binding of antibody (e.g., IgG) onto Fc receptors present on certain cytotoxic cells which enables the cytotoxic effector cells to bind to an antigen-bearing target cells and subsequently kill the target cell with cytotoxins. ADCP involves a cellular process wherein effector cells with phagocytic potential, such as monocytes, macrophages, neutrophils, and dendritic cells, can internalize and degrade the antigen-bearing target cells upon binding of antibody (e.g., IgG) onto Fc receptors of effector cells. CDC is a mechanism wherein when the antibody (e.g., IgG and IgM) binds to surface antigen on target cells, the classical complement pathway is triggered by binding protein C1q to these antibodies, leading to the formation of a membrane attack complex and target cell lysis.

II. Anti-CD47 Antibody and Fc-intact antibody

The interaction between CD47 that is expressed on tumor cells and SIRPα on macrophages facilitates a “don’ t-eat-me” signal that inhibits macrophage-mediated phagocytosis of tumor cells. Blockade of the CD47/SIRPa interaction using antibodies against CD47 or SIRPa-Fc fusion proteins promotes phagocytosis and tumor cell destruction, which represents a promising strategy for tumor immunotherapy. However, CD47 is ubiquitously expressed on all cells including erythrocytes and platelets, which form a large antigen sink and lead to potential hematological toxicities. In fact, anemia and thrombocytopenia have been observed in non-human primates and tumor patients that are subjected to anti-CD47 treatment in preclinical and clinical studies. Therefore, anti-CD47 antibody with reduced Fc-mediated antibody effector function (such as ADCC or CDC or ADCP) can be desired.

The anti-CD47 antibody as used herein can be a monoclonal antibody, a genetically engineered antibody, a humanized antibody, a chimeric antibody, or a human antibody. The anti-CD47 antibody can be selected from a Fab, a Fv, a scFv, a Fab’ , or a (Fab’ ) 2. The anti-CD47 antibody may be selected from an IgA, an IgG, and IgD. The anti-CD47 antibody may be an IgG. The anti-CD47 antibody may be an IgG4.

Exemplary anti-CD47 antibody that can be used in the methods as disclosed herein can be any of the CD47 antigen binding unit disclosed in PCT/CN2018/074318 (WO 2018/137705) , which are incorporated herein by reference in their entirety and for all purposes.

In some embodiments, the anti-CD47 antibody used in the method as disclosed herein comprises a variable light chain region and a variable heavy chain region, wherein the variable light chain region comprises CDR1 having the sequence of SEQ ID NO: 1, CDR2 having the sequence of SEQ ID NO: 2, and CDR3 having the sequence of SEQ ID NO: 3, the variable heavy chain region comprises CDR1 having the sequence of SEQ ID NO: 4, CDR2 having the sequence of SEQ ID NO: 5, and CDR3 having the sequence of SEQ ID NO: 6. In some embodiments, the anti-CD47 antibody used in the method disclosed herein is the H-ABU 41 antibody described in PCT/CN2018/074318.

In some embodiments, the anti-CD47 antibody used in the method as disclosed herein comprises the sequences of SEQ ID NOs: 7 and 8. In some embodiments, the anti-CD47 antibody comprise a Fc region which comprises a mutation to reduce Fc-mediated antibody effector function. In some embodiments, the anti-CD47 antibody also comprises a Fc region, which is either IgG4 with a S228 mutation (SEQ ID NO: 9) or IgG4 with both a S228P and L235E mutations (SEQ ID NO: 10) .

To mitigate the reduced phagocytosis function that can be elicited by the anti-CD47 antibody, a Fc-intact antibody and/or chemotherapy agent is used in combination with anti-CD47 antibody. The Fc-intact antibody can bind to at least one antigen other than CD47 that is also expressed on the surface of cancer cells. The at least one antigen can be HER2, EGFR, and CD20. Exemplary Fc-intact antibody accordingly include trastuzumab, cetuximab, and rituximab.

Examples 1-5 demonstrate enhanced tumor growth inhibition with the combinational use of anti-CD47 antibody, trastuzumab (cetuximab or rituximab) , and/or a chemotherapy agent in various xenograft cancer models.

Example 6 indicates that anti-CD47 antibodies as used herein can bind with CD47 on various of cancer cell lines in a dose dependent manner. Example 7 shows that anti-CD47 antibody potently blocks CD47/SIRPa interaction and promote phagocytosis in the in vitro co-culture system. Example 8 characterized cancer models by identifying CD47 surface expression levels and CD47, HER2, CD20 and EGFR transcript levels in cancer models by RT-qPCR analysis.

Further illustration of the use of anti-CD47 antibody is provided in the Example section below. The examples are provided as a guide to a practitioner of ordinary skill in the art and are not meant to be limiting in any way.

EXAMPLES

The anti-CD47 antibody used in the examples is a recombinant humanized IgG4 anti-

CD47 mAb. It can be prepared as described in PCT/CN2018/074318. It can also be prepared in CHO (Chinese Hamster Ovary) cells. The anti-CD47 antibody comprises S228P and L235E mutations in the hinge/Fc region. Trastuzumab was obtained from Roche (Herceptin, anti-ERBB2, human IgG1, SH0297) , Cetuximab was obtained from Merck KGaA (Erbitux, anti-EGFR, human IgG1, G00BME) , and Rituximab was obtained from Roche (anti-CD20, IgG1, H0270) .

The following Examples 1-5 describe in vivo xenograft studies. The HCC1954, SK-OV-3, FaDu, and Raji tumor cells were maintained in vitro with as a monolayer culture in RPMI-1640 or IMDM medium supplemented with 10%fetal bovine serum at 37℃ in an atmosphere of 5%CO₂ in air. The cells in exponential growth phase were harvested and quantitated by cell counter before tumor inoculation. Each mouse was inoculated subcutaneously in the right upper flank region with 5 x 10⁶ tumor cells in 0.1 ml of PBS mixed with Matrigel (1: 1) for tumor development. The randomization started when the mean tumor size reached ～100 mm³. A total of 80 mice were enrolled in the study and allocated into 8 groups with 10 mice per group. Randomization was performed based on "Matched distribution" method (Study Director ^TM software, version 3.1.399.19) . The date of grouping was denoted as day 0. Dosing started from day 0 through day 35-91. After tumor inoculation, the animals were checked daily for morbidity and mortality. During routine monitoring, the animals were checked for any effects of tumor growth and treatments on behavior such as mobility, food and water consumption, body weight gain/loss (Body weights would be measured three times/daily per week after randomization) , eye/hair matting and any other abnormalities. Mortality and observed clinical signs were recorded for individual animals in detail. Tumor volumes were measured three times per week after randomization in two dimensions using a caliper, and the volume was expressed in mm³ using the formula: V = (L x W x W) /2, where V is tumor volume, L is tumor length (the longest tumor dimension) , and W is tumor width (the longest tumor dimension perpendicular to L) . Dosing as well as tumor and body weight measurements were conducted in a Laminar Flow Cabinet. The body weights and tumor volumes were measured by using Study Director ^TM software (version 3.1.399.19)

The PDX model of ST-02-0077 was originally established from a surgically resected clinical sample and implanted in nude mice defined as passage 0 (P0) . The next passage implanted from P0 tumor was defined as passage1 (P1) , or (FP1) if it was revived from the frozen P0 tumor, and further passages were generated by serial implantation in mice. The FP4 tumor tissue was used for the study. BALB/c Nude, female, 6～8 weeks, weighing approximately 16～18g. A total of 200 (80 plus 150%) were used for the study, which were purchased from Beijing Vital River Laboratory Animal Co., LTD., or other certified vendors. Each mouse was implanted subcutaneously at the right flank with the ST-02-0077 FP4 tumor slices (～30 mm³) for tumor development. The animals were randomized, and treatment was started when the average tumor size reaches approximately 150-200 mm³ for the efficacy study. The test article administrations in each group are shown as indicated in FIG. 1-5.

Example 1

Anti-CD47 Antibody in Combination with Trastuzumab and Docetaxel Showed Enhanced Anti-Tumor Activity in HCC1954 Breast Cancer Xenograft Model

HCC1954 cells were inoculated subcutaneously (SC) into Balb/c Nude mice. When tumors reach 100 mm³, Mice were randomized and treated with 10 mg/kg of isotype control or anti-CD47 antibody (for the ease of reference, anti-CD47 is used in all tables and figures in thisapplication) intraperitoneally (IP) twice per week (BIW) , 1 mg/kg of trastuzumab intraperitoneally (IP) once per week (QW) , 2 mg/kg of docetaxel, IP, QW, or their combinations as indicated. Tumor sizes were measured twice per week and tumor growth curves in FIG. 1 were shown as mean + SEM. Table 1 below shows tumor growth inhibition (%TGI) per treatment groups at days after the start of the treatment.

Table 1

Example 2

Anti-CD47 Antibody in Combination with Trastuzumab and Paclitaxel Showed Enhanced Anti-Tumor Activity in SK-OV-3 Ovarian Cancer Xenograft Model

SK-OV-3 cells were inoculated subcutaneously (SC) into Balb/c Nude mice. When tumors reach 100 mm³, Mice were randomized and treated with 10 mg/kg of isotype control or anti-CD47 antibody IP, BIW, 2 mg/kg of trastuzumab, IP, QW, 7.5 mg/kg of paclitaxel, intravenously (IV) , QW, or their combinations as indicated. Tumor sizes were measured twice per week and tumor growth curves in FIG. 2 were shown as mean + SEM. Table 2 below shows tumor growth inhibition (%TGI) per treatment groups at days after the start of the treatment.

Table 2

Example 3

Anti-CD47 Antibody in Combination with Trastuzumab and Docetaxel Showed Enhanced Anti-Tumor Activity in ST-02-0077 Gastric Cancer Patient-Derived-Xenograft (PDX) Model

ST-02-0077 PDX were inoculated subcutaneously (SC) into Balb/c Nude mice. When tumors reach 100 mm3, Mice were randomized and treated with 10 mg/kg of isotype control or anti-CD47 antibody, IP, BIW, 5 mg/kg of trastuzumab, IP, BIW. 4 mg/kg of docetaxel, IV, BIW, or their combinations as indicated. Tumor sizes were measured twice per week and tumor growth curves in FIG. 3 were shown as mean + SEM. Table 3 below shows tumor growth inhibition (%TGI) per treatment groups at days after the start of the treatment.

Table 3

Example 4

Anti-CD47 Antibody in Combination with Cetuximab and Cisplatin Showed Enhanced Anti-Tumor Activity in FaDu Head and Neck Squamous Cell Carcinomas (HNSCC) Xenograft Model

FaDu cells were inoculated subcutaneously (SC) into Balb/c Nude mice. When tumors reach 100 mm³, Mice were randomized and treated with 10 mg/kg of isotype control or anti-CD47 antibody, IP, BIW, 0.5 mg/kg of Cetuximab, IP, QW, 5 mg/kg of Cisplatin, IV, QW, or their combinations as indicated. Tumor sizes were measured twice per week and tumor growth curves in FIG. 4 were shown as mean + SEM. Table 4 below shows tumor growth inhibition (%TGI) per treatment groups at days after the start of the treatment.

Table 4

Example 5

Anti-CD47 Antibody in Combination with Rituximab Showed Enhanced Anti-Tumor Activity in Raji Lymphoma Xenograft Model

Raji cells were inoculated subcutaneously (SC) into Balb/c Nude mice. When tumors reach 100 mm3, Mice were randomized and treated with 10 mg/kg of isotype control or 1 mg/kg of anti-CD47 antibody, IP, BIW, 10 mg/kg of Rituximab, IP, QW, or their combinations as indicated. Tumor sizes were measured twice per week and tumor growth curves in FIG. 5 were shown as mean + SEM. Table 5 below shows tumor growth inhibition (%TGI) per treatment groups at days after the start of the treatment.

Table 5

Examples 6-8 describes in vitro binding assays of anti-CD47 antibody to CD47 in various cell lines, as well as cancer cell characterizations.

Cells and cell culture

BT-474, HCC1954, HCC202, SK-OV-3, HCC2218, AU565, Toledo, Raji, Jurkat, Pfeiffer, FaDu, NCI-H747, SW48, and CAL27 were purchased from ATCC and cultured in medium per instructions of ATCC with 10%fetal bovine serum at 37℃ in an atmosphere of 5%CO₂ in air.

Cell-based CD47 signaling bioassay

The evaluation of anti-CD47 antibody in blocking CD47-SIRPa signaling pathway was performed using cell-based PathHunter CD47/SIRPα signaling assay (Eurofins DiscoverX, 93-1135Y19-00130) . Briefly, 40 uL of CD47-presenting ligand cells were seeded into white 96-well microplates at a cell density of 0.75x10⁶ cells /well. Then, 20 uL of serial diluted anti-CD47 antibody was added to each well followed by adding 40 uL of SIRPα signaling cells. The plate was incubated at 37 ℃ in 5%CO₂ for 24 hours. The assay signal was generated using PathHunter Bioassay Detection Kit. Ten microliters of detection reagent 1 was added to the assay and incubated at room temperature for 15 min in the dark. Subsequently, 40 uL of detection reagent 2 was added and incubated at room temperature for 1 hour. Microplates were read with BioTek instrument for chemiluminescent signal detection.

Real time PCR

RNAs from cell lines were extracted using QIACube Connect per manufacturer’s instructions (Qiagen) . RT-qPCR reactions were set up using 3 μL of diluted RNAs (5 ng/uL) with 7 μL of pre-mixed SensiFAST^TM SYBR No-ROX One-Step Kit reagents (BIOLINE, Cat#BIO-98005) and RT-qPCR was run on a Bio-Rad CFX384 Real-Time RT-qPCR System. The relative mRNA levels of CD47, HER2, CD20 and EGFR were relative to the internal control RPL27.

Macrophage differentiation

Human PBMCs were obtained from StemCell Technologies (70034) . Monocytes were purified from PBMCs using EasySep Human Monocyte Isolation Kit (StemCell Technologies, 19359) and then placed in a 10-cm dish and cultured with RPMI 1640 medium containing 10%human serum (Fisher Scientific, BP2525100) with macrophage colony-stimulating factor (PeproTech, 300-25) . Fresh medium was added on days 3 and 6. Macrophages were harvested on day 7 to 10, used immediately for downstream experiments, or froze in the vapor phase of liquid nitrogen for later use. Phagocytosis index is the number of phagocytosed tumor cells per 100 macrophages.

Example 6

Dose Dependent Assay

In vitro binding of anti-CD47 antibody with CD47 on cell lines OVCAR-3 (A) , HCC1954 (B) , SK-OV-3 (C) , and Jurkat (E) was performed. The binding curve in FIG. 6A-D showed the binding in a dose dependent manner.

Example 7

Anti-CD47 Antibody Blocking CD47/SIRPa Interaction and Promoting Phagocytosis

This experiment showed that anti-CD47 antibody potently blocked CD47/SIRPa interaction through PathHunter SIRPa signaling (FIG. 7A) . Anti-CD47 antibody promoted phagocytosis in in vitro co-culture system with differentiated macrophages and tumor cells including Toledo (FIG. 7B) , OVCAR-3 (FIG. 7C) , and FaDu (FIG. 7D) . Anti-CD47 promoted phagocytosis in in vitro co-culture system with differentiated macrophages and tumor cells including Toledo (FIG. 7E) and FaDu (FIG. 7F) in a dose-dependent manner.

Example 8

Characterization of Cancer Models

CD47 surface expression levels in various cancer models were obtained by flow cytometry analysis (FIG. 8A) . CD47, HER2, CD20 and EGFR transcript levels in cancer models was obtained by RT-qPCR analysis (FIG. 8B-E)

______________________________________________________________________________

Claims

A method of treating cancer in a subject in need thereof, wherein the method comprises administering to the subject an effective amount of (1) an anti-CD47 antibody, (2) a Fc-intact antibody, and optionally (3) a chemotherapy agent.
The method of claim 1, wherein the method comprises administering to the subject an effective amount of (1) an anti-CD47 antibody, (2) a Fc-intact antibody, and (3) a chemotherapy agent.
The method of claim 1 or 2, wherein the cancer has elevated expression levels of CD47 and another antigen against which the Fc-intact antibody binds, or the cancer has elevated expression level of CD47 with positive expression of another antigen against which the Fc-intact antibody binds.
The method of any of claims 1-3, wherein the anti-CD47 antibody comprises a variable light chain region and a variable heavy chain region, wherein the variable light chain region comprises CDR1 having the sequence of SEQ ID NO: 1, CDR2 having the sequence of SEQ ID NO: 2, and CDR3 having the sequence of SEQ ID NO: 3, the variable heavy chain region comprises CDR1 having the sequence of SEQ ID NO: 4, CDR2 having the sequence of SEQ ID NO: 5, and CDR3 having the sequence of SEQ ID NO: 6.
The method of any of claims 1-4, wherein the anti-CD47 antibody comprises the sequences of SEQ ID NOs: 7 and 8.
The method of any of claims 1-5, wherein another antigen is selected from HER2, EGFR, and CD20.
The method of any of claims 1-6, wherein the Fc-intact antibody is selected from trastuzumab, cetuximab, and rituximab.
The method of any of claims 1-7, wherein the chemotherapy agent is selected from platinum compound and taxanes.
The method of any of claims 1-7, wherein the chemotherapy agent is selected from cisplatin, carboplatin and oxaliplatin.
The method of any of claims 1-7, wherein the chemotherapy agent is cisplatin.
The method of any of claims 1-7, wherein the chemotherapy agent is selected from paclitaxel and docetaxel.
The method of any of claims 1-11, wherein the cancer is selected from breast cancer, ovarian cancer, gastric cancer, head and neck squamous cell carcinomas, and lymphoma.
The method of any of claims 1-11, wherein the cancer is gastric cancer, breast cancer, and ovarian cancer having elevated expression levels of both CD47 and HER2, wherein the Fc-intact antibody is trastuzumab, and wherein the chemotherapy agent is docetaxel or paclitaxel.
The method of any of claims 1-11, wherein the cancer is head and neck squamous cell carcinomas having elevated expression level of CD47, with positive EGFR expression, wherein the Fc-intact antibody is cetuximab, and wherein the chemotherapy agent is cisplatin.
The method of any of claims 1-11, wherein the cancer is lymphoma having elevated expression level of CD47, with positive CD20 expression, wherein the Fc-intact antibody is rituximab, and wherein the chemotherapy agent is cisplatin, docetaxel, or paclitaxel.
The method of any of claims 1-15, wherein the method comprises administering the anti-CD47 antibody at a dose of 0.1-30 mg/kg once or twice weekly to the subject.
The method of any of claims 1-15, wherein the method comprises administering anti-CD47 antibody at a dose of 0.1, 0.3, 1, 3, 5, 10, 15, 20, 25, or 30 mg/kg once or twice weekly to the subject.
The method of any of claims 1-17, wherein the anti-CD47 antibody can be selected from a Fab, a Fv, a scFv, a Fab’, or a (Fab’) 2.
The method of any of claims 1-17, wherein the anti-CD47 antibody is an IgG4 based antibody.
The method of any of claims 1-17, wherein the anti-CD47 antibody is a recombinant, humanized IgG4 mAb comprising a L235E mutation in the Fc region.