WO2023227115A1

WO2023227115A1 - A method of treating solid tumor

Info

Publication number: WO2023227115A1
Application number: PCT/CN2023/096583
Authority: WO
Inventors: Pengfei Song; Yuan MENG; Cong XU
Original assignee: I-Mab Biopharma Co., Ltd.; Shanghai Junshi Biosciences Co., Ltd.
Priority date: 2022-05-26
Filing date: 2023-05-26
Publication date: 2023-11-30

Abstract

Use of a CD73 antibody or an antigen binding fragment thereof in preparing a medicament for treating solid tumor in a subject in need thereof, wherein the medicament further comprising a PD-1 antagonist.

Description

A METHOD OF TREATING SOLID TUMOR

FIELD

The present application relates to a method of treating solid tumor. In particular, provided is a method of treating solid tumor, such as advanced solid tumor, by using an anti-CD73 antibody or an antigen binding fragment thereof.

BACKGROUND

CD73, cluster of differentiation 73, is also known as 5’ -nucleotidase (5'-NT) or ecto-5’ -nucleotidase, is an enzyme serves to convert AMP to adenosine. CD73 catalyzes the formation of extracellular adenosine which contributes to the immunosuppressive tumor environment. CD73 is over-expressed in stromal cells and multiple types of tumor cells, as well as in Tregs, M2 and myeloid derived suppressor cells (MDSCs) .

Preclinical evidence shows that CD73 inhibition prevented adenosine-mediated lymphocyte suppression, increased the activity of CD8+ effector cells, and reduced both MDSCs and Tregs. There are a few anti-CD73 antibodies being developed as potential anticancer agents, but none have been approved for clinical use.

SUMMARY

The present application addresses clinical needs of treatment by using CD73 antibody.

In one aspect, provided herein is a method of treating solid tumor, comprising administering to a subject in need thereof a CD73 antibody or an antigen binding fragment thereof at a dosage of about 2 to about 60 mg/kg body weight and a PD-1 antagonist.

In some embodiments of the method of the present application, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 15 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 5 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 20 to about 30 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2, about 5, about 10, about 15 or about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 20 or 30 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administered to the subject once weekly (QW) , once every two weeks (Q2W) , once every three weeks (Q3W) , once every four weeks (Q4W) or once monthly. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject once every three weeks (Q3W) . In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dosage of 20 or 30 mg/kg once every three weeks (Q3W) . In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject intravenously.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is selected from a group consisting of a full-length antibody, Fab, Fab’ , F (ab’ ) 2, scFv, and sdAb. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is a full-length antibody. In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises a HCDR1, a HCDR2, and a HCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a heavy variable region (VH) as set forth in SEQ ID NO. 1, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme. In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises: (1) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 3 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 3, (2) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 4 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 4, and (3) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 5 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 5. In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises a heavy variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 1 or an amino acid sequence having at least 90%identity with SEQ ID NO. 1.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises a LCDR1, a LCDR2, and a LCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a light variable region (VL) as set forth in SEQ ID NO. 2, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme. In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises: (1) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 6 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 6, (2) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 7 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 7, and (3) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 8 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 8. In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises a light variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 2 or an amino acid sequence having at least 90%identity with SEQ ID NO. 2.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises: (1) HCDR1, a HCDR2, and a HCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a heavy variable region (VH) as set forth in SEQ ID NO. 1, and (2) LCDR1, a LCDR2, and a LCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a light variable region (VL) as set forth in SEQ ID NO. 2, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme. In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises: (1) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 3 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 3, (2) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 4 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 4, (3) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 5 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 5, (4) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 6 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 6, (5) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 7 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 7, and (6) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 8 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 8.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof comprises: (1) a heavy variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 1 or an amino acid sequence having at least 90%identity with SEQ ID NO. 1, and (2) a light variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 2 or an amino acid sequence having at least 90%identity with SEQ ID NO. 2.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is selected from the group consisting of uliledlimab (I-Mab Biopharma) , oleclumab (AstraZeneca) , CPI-006 (Corvus Pharma) , BMS-986179 (Bristol-Myers Squibb) , AB-680 (Arcus Biosciences) , NZV-930 (SRF373, Surface Oncolohgy/Novartis) , JAB-BX102 (Jacobio) , AK119 (Akesobio) , Sym024 (Symphogen) , IBI 325 (Innovent) , BR 101 (Hisun BioRay) , and LY3475070 (Eli-Lilly) .

In some embodiments, the solid tumor is selected from the group consisting of ovarian cancer, sarcoma, cervical cancer, bladder cancer, breast cancer, colorectal cancer, endometrial cancer, esophageal cancer, head and neck cancer, kidney cancer, liver cancer, lung cancer, lymphoma, acute lymphoid leukemia, multiple myeloma, glioma, mesothelial, melanoma, skin cancer (basal cell cancer) , pancreatic cancer, prostate cancer, uterine cancer, and thyroid cancer.

In some embodiments, the lung cancer comprises non-small cell lung cancer (NSCLC) and small lung cancer (SCLC) . In some embodiments, the solid tumor is advanced solid tumor. In some embodiments, the solid tumor is metastatic solid tumor. In some embodiments, the solid tumor is relapsed solid tumor. In some embodiments, the solid tumor is refractory solid tumor. In some embodiments, the solid tumor is in stage III or stage IV.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof and the PD-1 antagonist are administrated concurrently. In some embodiments, the CD73 antibody or the antigen binding fragment thereof and the PD-1 antagonist are administrated separately.

In some embodiments, the PD-1 antagonist is a PD-1 antibody. In some embodiments, the PD-1 antibody comprises: (1) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 10 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 10, (2) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 11 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 11, (3) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 12 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 12, (4) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 13 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 13, (5) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 14 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 14, and (6) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 15 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 15. In some embodiments, the PD-1 antibody comprises: (1) a heavy variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 16 or an amino acid sequence having at least 90%identity with SEQ ID NO. 16, and (2) a light variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 17 or an amino acid sequence having at least 90%identity with SEQ ID NO. 17.

In some embodiments, the PD-1 antibody is selected from the group consisting of pembrolizumab, nivolumab, toripalimab, pidilizumab, cemiplimab, sintilimab, cetrelimab, spartalizumab, camrelizumab, tislelizumab, balstilimab, dostarlimab, ABBV-181, penpulimab, genolimzumab, retifanlimab, sasanlimab, AMP-224, AB122, F-520, MEDI-3387, MEDI-5771, MEDI-0680, SG-001, BCD-100, BAT-1306, BI-754091, CBT-501, GLS-010, LZM-009, Sym-021, CS-1003, HLX-10, AK-103, AM-0001, ENUM-244C8, ENUM-388D4, JTX-4014, RXI-762, STI-A1110, HLX-20, SSI-361, APL-501, TJ0141H, and SNA-01. In some embodiments, the PD-1 antibody is Toripalimab. In some embodiments, the PD-1 antibody is administrated to the subject at a dosage of 240 mg flat dose once every three weeks (Q3W) .

In some embodiments, the subject has a tumor tissue in which at least 40%of the tumor cells are CD73 positive. In some embodiments, the subject has a tumor tissue in which at least 30%, 35%, 40%, 45%or 50%of the tumor cells are CD73 positive. In some embodiments, the at least 1%of the tumor cells are PD-L1 positive.

In another aspect, provided herein is use of a CD73 antibody or an antigen binding fragment thereof in preparing a medicament for treating solid tumor in a subject in need thereof, wherein the medicament is administered to the subject at a dosage of about 2 to about 60 mg/kg body weight in combination with a PD-1 antagonist.

In another aspect, provided herein is an article of manufacture, comprising: (1) a CD73 antibody or an antigen binding fragment thereof, and (2) a package insert which suggests administration of the CD73 antibody or the antigen binding fragment thereof to a subject in need thereof at a dosage of about 2 to about 30 mg/kg body weight in combination with a PD-1 antagonist. In some embodiments, the article of manufacture further comprises the PD-1 antagonist

It is to be understood that one, some, or all of the properties of the various embodiments described herein may be combined to form other embodiments of the present invention. These and other aspects of the invention will become apparent to one of skill in the art. These and other embodiments of the invention are further described by the detailed description that follows.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a simulated pharmacokinetic profile for Uliledlimab at proposed regimen of 30 mg/kg Q3W with an additional dose on C1D8 based on a population pharmacokinetic model established upon the observed pharmacokinetic results.

FIG. 2A-2F shows the expression level of total and free CD73 as measured by immunohistochemical (IHC) staining and the residual CD73 enzymatic activity as measured by enzyme-histochemistry (EHC) staining in tumor biopsies obtained from two NSCLC patients treated with 30 mg/kg Uliledlimab. Tumor biopsy samples were collected at C_trough timepoint cycle 4, day 1 (C4D1) .

FIG. 3 shows a receiver operating characteristic (ROC) analysis to identify CD73 level cutoff value.

FIG. 4 shows that the combination treatment achieved a better clinical response in patients with higher CD73 expression (≥40%) , especially in those patients with PD-L1 TPS 1-49%and ≥ 50%

DETAILED DESCRIPTION

Definitions

Before describing the embodiments in detail, it is to be understood that the present disclosure is not limited to particular compositions or biological systems, which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting.

As used in this specification and the appended claims, the singular forms “a” , “an” and “the” include plural referents unless the content clearly dictates otherwise. Thus, for example, reference to “a molecule” optionally includes a combination of two or more such molecules, and the like.

The term “about” as used herein refers to the usual error range for the respective value readily known to the skilled person in this technical field. Reference to “about” a value or parameter herein includes (and describes) embodiments that are directed to that value or parameter per se.

It is understood that aspects and embodiments of the present disclosure include “comprising, ” “consisting, ” and “consisting essentially of” aspects and embodiments.

As used herein, the term “antibody” is used in the broadest sense and specifically covers intact antibodies (e.g., full length antibodies) , antibody fragments (including without limitation Fab, F (ab’ ) 2, scFv, scFv-Fc, single domain antibodies, single heavy chain antibodies, and single light chain antibodies) , monoclonal antibodies, and polyclonal antibodies, so long as they exhibit the desired biological activity (e.g., epitope binding) .

As used herein, the term “isolated” antibody may refer to an antibody that is substantially free of other cellular material. In one embodiment, an isolated antibody is substantially free of other proteins from the same species. In another embodiment, an isolated antibody is expressed by a cell from a different species and is substantially free of other proteins from the different species. In some embodiments, an “isolated” antibody is one which has been identified and separated and/or recovered from a component of its natural environment. Contaminant components of its natural environment are materials which would interfere with diagnostic or therapeutic uses for the antibody, and may include enzymes, hormones, and other proteinaceous or nonproteinaceous solutes. An antibody may be rendered substantially free of naturally associated components (or components associated with the cellular expression system used to produce the antibody) by isolation, using protein purification techniques well known in the art. In some embodiments, the antibody will be purified (1) to greater than 75%by weight of antibody as determined by the Lowry method, and most preferably more than 80%, 90%, 95%or 99%by weight, or (2) to homogeneity by SDS-PAGE under reducing or nonreducing conditions using Coomassie blue or, preferably, silver stain. Isolated antibody includes the antibody in situ within recombinant cells since at least one component of the antibody's natural environment will not be present. Ordinarily, however, isolated antibody will be prepared by at least one purification step.

As used herein, the term “native antibodies and immunoglobulins” are usually heterotetrameric glycoproteins of about 150, 000 daltons, composed of two identical light (L) chains and two identical heavy (H) chains. Each light chain is linked to a heavy chain by one covalent disulfide bond (also termed a “VH/VL pair” ) , while the number of disulfide linkages varies between the heavy chains of different immunoglobulin isotypes. Each heavy and light chain also has regularly spaced intrachain disulfide bridges. Each heavy chain has at one end a variable domain (VH) followed by a number of constant domains. Each light chain has a variable domain at one end (VL) and a constant domain at its other end; the constant domain of the light chain is aligned with the first constant domain of the heavy chain, and the light chain variable domain is aligned with the variable domain of the heavy chain. Particular amino acid residues are believed to form an interface between the light-and heavy-chain variable domains. See, e.g., Chothia et al., J. Mol. Biol., 186: 651 (1985) ; Novotny and Haber, Proc. Natl. Acad. Sci. U.S.A., 82: 4592 (1985) .

As used herein, the term “variable” refers to the fact that certain portions of the variable domains differ extensively in sequence among antibodies and are used in the binding and specificity of each particular antibody for its particular antigen. However, the variability is not evenly distributed throughout the variable domains of antibodies. It is concentrated in three segments called complementarity-determining regions (CDRs) or hypervariable regions both in the light-chain and the heavy-chain variable domains. The more highly conserved portions of variable domains are called the framework (FR) . The variable domains of native heavy and light chains each comprise four FR regions, largely adopting a β-sheet configuration, connected by three CDRs, which form loops connecting, and in some cases forming part of, the β-sheet structure. The CDRs in each chain are held together in close proximity by the FR regions and, with the CDRs from the other chain, contribute to the formation of the antigen-binding site of antibodies. See, e.g., Kabat et al., Sequences of Proteins of Immunological Interest, Fifth Edition, National Institute of Health, Bethesda, Md. (1991) . The constant domains are not involved directly in binding an antibody to an antigen, but exhibit various effector functions, such as participation of the antibody in antibody-dependent cellular toxicity. Variable region sequences of interest include the humanized variable region sequences for CD47 antibodies described in detail elsewhere herein.

The term “hypervariable region (HVR) ” or “complementarity determining region (CDR) ” may refer to the subregions of the VH and VL domains characterized by enhanced sequence variability and/or formation of defined loops. These include three CDRs in the VH domain (H1, H2, and H3) and three CDRs in the VL domain (L1, L2, and L3) . H3 is believed to be critical in imparting fine binding specificity, with L3 and H3 showing the highest level of diversity. See Johnson and Wu, in Methods in Molecular Biology 248: 1-25 (Lo, ed., Human Press, Totowa, N. J., 2003) .

A number of CDR/HVR delineations are known. The Kabat Complementarity Determining Regions (CDRs) are based on sequence variability and are the most commonly used (Kabat et al., Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md. (1991) ) . Chothia refers instead to the location of the structural loops (Chothia and Lesk J. Mol. Biol. 196: 901-917 (1987) ) . The AbM HVRs represent a compromise between the Kabat HVRs and Chothia structural loops, and are used by Oxford Molecular's AbM antibody modeling software. The “contact” HVRs are based on an analysis of the available complex crystal structures. The residues from each of these HVRs/CDRs are noted below. “Framework” or “FR” residues are those variable domain residues other than the HVR/CDR residues

“Extended” HVRs are also known: 24-36 or 24-34 (L1) , 46-56 or 50-56 (L2) and 89-97 or 89-96 (L3) in the VL and 26-35 (H1) , 50-65 or 49-65 (H2) and 93-102, 94-102, or 95-102 (H3) in the VH (Kabat numbering) .

“Numbering according to Kabat” may refer to the numbering system used for heavy chain variable domains or light chain variable domains of the compilation of antibodies in Kabat et al., supra. The actual linear amino acid sequence may contain fewer or additional amino acids corresponding to a shortening of, or insertion into, a FR or HVR of the variable domain. The Kabat numbering of residues may be determined for a given antibody by alignment at regions of homology of the sequence of the antibody with a “standard” Kabat numbered sequence. Typically, the Kabat numbering is used when referring to a residue in the variable domains (approximately residues 1-107 of the light chain and residues 1-113 of the heavy chain) , whereas the EU numbering system or index (e.g., the EU index as in Kabat, numbering according to EU IgG1) is generally used when referring to a residue in the heavy chain constant region.

As used herein, the term “antibody fragment” , and all grammatical variants thereof, are defined as a portion of an intact antibody comprising the antigen binding site or variable region of the intact antibody which, in certain instances, is free of the constant heavy chain domains (i.e. CH2, CH3, and/or CH4, depending on antibody isotype) of the Fc region of the intact antibody. Examples of antibody fragments include Fab, Fab’ , Fab’ -SH, F (ab’ ) ₂, and Fv fragments; diabodies; any antibody fragment that is a polypeptide having a primary structure consisting of one uninterrupted sequence of contiguous amino acid residues (referred to herein as a “single-chain antibody fragment” or “single chain polypeptide” ) , including without limitation (1) single-chain Fv (scFv) molecules, (2) single chain polypeptides containing only one light chain variable domain, or a fragment thereof that contains the three CDRs of the light chain variable domain, without an associated heavy chain moiety, and (3) single chain polypeptides containing only one heavy chain variable region, or a fragment thereof containing the three CDRs of the heavy chain variable region, without an associated light chain moiety; and multi-specific or multivalent structures formed from antibody fragments. In an antibody fragment comprising one or more heavy chains, the heavy chain (s) can contain any constant domain sequence (e.g. CH1 in the IgG isotype) found in a non-Fc region of an intact antibody, and/or can contain any hinge region sequence found in an intact antibody, and/or can contain a leucine zipper sequence fused to or situated in the hinge region sequence or the constant domain sequence of the heavy chain (s) .

The Fab fragment also contains the constant domain of the light chain and the first constant domain (CH₁) of the heavy chain. Fab’ fragments differ from Fab fragments by the addition of a few residues at the carboxy terminus of the heavy chain CH₁ domain including one or more cysteines from the antibody hinge region. Fab’ -SH is the designation herein for Fab’ in which the cysteine residue (s) of the constant domains bear a free thiol group. F (ab’ ) ₂ antibody fragments originally were produced as pairs of Fab’ fragments which have hinge cysteines between them. Other chemical couplings of antibody fragments are also known.

As used herein, the term “monoclonal antibody” (mAb) refers to an antibody obtained from a population of substantially homogeneous antibodies, i.e., the individual antibodies comprising the population are identical except for possible naturally occurring mutations that may be present in minor amounts. Monoclonal antibodies are highly specific, being directed against a single antigenic site. Each mAb is directed against a single determinant on the antigen. In addition to their specificity, the monoclonal antibodies are advantageous in that they can be synthesized by hybridoma culture, uncontaminated by other immunoglobulins. The modifier “monoclonal” indicates the character of the antibody as being obtained from a substantially homogeneous population of antibodies, and is not to be construed as requiring production of the antibody by any particular method. For example, the monoclonal antibodies to be used in accordance with the present invention may be made in an immortalized B cell or hybridoma thereof, or may be made by recombinant DNA methods.

The monoclonal antibodies herein include hybrid and recombinant antibodies produced by splicing a variable (including hypervariable) domain of an CD47 antibody with a constant domain (e.g. “humanized” antibodies) , or a light chain with a heavy chain, or a chain from one species with a chain from another species, or fusions with heterologous proteins, regardless of species of origin or immunoglobulin class or subclass designation, as well as antibody fragments (e.g., Fab, F (ab’ ) ₂, and Fv) , so long as they exhibit the desired biological activity.

The monoclonal antibodies herein specifically include chimeric antibodies (immunoglobulins) in which a portion of the heavy and/or light chain is identical with or homologous to corresponding sequences in antibodies derived from a particular species or belonging to a particular antibody class or subclass, while the remainder of the chain (s) is identical with or homologous to corresponding sequences in antibodies derived from another species or belonging to another antibody class or subclass, as well as fragments of such antibodies, so long as they exhibit the desired biological activity.

As used herein, the term “treatment” refers to clinical intervention designed to alter the natural course of the individual or cell being treated during the course of clinical pathology. Desirable effects of treatment include decreasing the rate of disease progression, ameliorating or palliating the disease state, and remission or improved prognosis. For example, an individual is successfully “treated” if one or more symptoms associated with cancer are mitigated or eliminated, including, but are not limited to, reducing the proliferation of (or destroying) cancerous cells, decreasing symptoms resulting from the disease, increasing the quality of life of those suffering from the disease, decreasing the dose of other medications required to treat the disease, and/or prolonging survival of individuals. In some embodiments, “treating” a disease such as cancer refers to delaying progression of the disease, i.e., deferring, hindering, slowing, retarding, stabilizing, and/or postponing development of the disease (such as cancer) . This delay can be of varying lengths of time, depending on the history of the disease and/or individual being treated. As is evident to one skilled in the art, a sufficient or significant delay can, in effect, encompass prevention, in that the individual does not develop the disease. For example, a late stage cancer, such as development of metastasis, may be delayed.

As used herein, the term “subject” for purposes of treatment refers to any animal classified as a mammal, including humans, domestic and farm animals, and zoo, sports, or pet animals, such as dogs.

The term “advanced solid tumor” as used herein refers to a solid tumor that cannot be cured or grows beyond the initial site of origin, either locally advanced or metastatic. In some embodiments, the advanced solid tumor includes but is not limited to solid tumors in stage III or stage IV.

The term “metastatic” or “metastasis” as used herein refers to a tumor spread from an initial or primary site to a different or secondary site within the subject’s body. It is generally distinguished from cancer invasion, which is the direct extension and penetration by cancer cells into neighboring tissues.

The term “refractory” as used herein refers to a disorder, disease, or condition that has not responded to prior treatment that can include one or more lines of therapy.

CD73 antibody

Any CD73 antibody known in the art can be used in the present application. In some embodiments, the CD73 antibody is selected from a group consisting of a full-length antibody, Fab, Fab’ , F (ab’ ) 2, scFv, and sdAb. In some embodiments, the CD73 antibody is a full-length antibody.

In some embodiments, the CD73 antibody comprises a HCDR1, a HCDR2, and a HCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a heavy variable region (VH) as set forth in SEQ ID NO. 1, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme. In some embodiments, the CD73 antibody comprises: (1) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 3 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 3, (2) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 4 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 4, and (3) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 5 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 5.

In some embodiments, the CD73 antibody comprises a heavy variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 1 or an amino acid sequence having at least 80%, 85%, 87%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity with SEQ ID NO. 1.

In some embodiments, the CD73 antibody comprises a LCDR1, a LCDR2, and a LCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a light variable region (VL) as set forth in SEQ ID NO. 2, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme. In some embodiments, the CD73 antibody comprises: (1) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 6 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 6, (2) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 7 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 7, and (3) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 8 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 8.

In some embodiments, the CD73 antibody comprises a light variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 2 or an amino acid sequence having at least 80%, 85%, 87%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity with SEQ ID NO. 2.

In some embodiments, the CD73 antibody comprises: (1) HCDR1, a HCDR2, and a HCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a heavy variable region (VH) as set forth in SEQ ID NO. 1, and (2) LCDR1, a LCDR2, and a LCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a light variable region (VL) as set forth in SEQ ID NO. 2, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme.

In some embodiments, the CD73 antibody comprises: (1) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 3 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 3, (2) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 4 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 4, (3) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 5 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 5, (4) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 6 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 6, (5) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 7 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 7, and (6) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 8 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 8.

In some embodiments, the CD73 antibody comprises: (1) a heavy variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 1 or an amino acid sequence having at least 80%, 85%, 87%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity with SEQ ID NO. 1, and (2) a light variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 2 or an amino acid sequence having at least 80%, 85%, 87%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity with SEQ ID NO. 2.

In some embodiments, the CD73 antibody is selected from the group consisting of uliledlimab (I-Mab Biopharma) , oleclumab (AstraZeneca) , CPI-006 (Corvus Pharma) , BMS-986179 (Bristol-Myers Squibb) , AB-680 (Arcus Biosciences) , NZV-930 (SRF373, Surface Oncolohgy/Novartis) , JAB-BX102 (Jacobio) , AK119 (Akesobio) , Sym024 (Symphogen) , IBI 325 (Innovent) , BR 101 (Hisun BioRay) , and LY3475070 (Eli-Lilly) . In some embodiments, the CD73 antibody is uliledlimab (I-Mab Biopharma) or oleclumab (AstraZeneca) .

PD-1 antagonist

Any suitable PD-1 antagonist known in the art can be used in the present application. In some embodiments, the PD-1 antagonist includes a small molecule inhibitor of PD-1 signaling. In some embodiments, the PD-1 antagonist includes an antibody or an antigen binding fragment thereof, such as an PD-1 antibody or an antigen binding fragment thereof. In some embodiments, the PD-1 antagonist is an PD-1 antibody or an antigen binding fragment thereof.

In some embodiments, the PD-1 antibody comprises a HCDR1, a HCDR2, and a HCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a heavy variable region (VH) as set forth in SEQ ID NO. 17, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme. In some embodiments, the CD73 antibody comprises: (1) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 13 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 13, (2) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 14 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 14, and (3) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 15 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 15.

In some embodiments, the PD-1 antibody comprises a heavy variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 17 or an amino acid sequence having at least 80%, 85%, 87%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity with SEQ ID NO. 17.

In some embodiments, the PD-1 antibody comprises a LCDR1, a LCDR2, and a LCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a light variable region (VL) as set forth in SEQ ID NO. 16, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme. In some embodiments, the CD73 antibody comprises: (1) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 10 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 10, (2) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 11 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 11, and (3) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 12 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 12.

In some embodiments, the PD-1 antibody comprises a light variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 2 or an amino acid sequence having at least 80%, 85%, 87%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity with SEQ ID NO. 16.

In some embodiments, the PD-1 antibody comprises: (1) HCDR1, a HCDR2, and a HCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a heavy variable region (VH) as set forth in SEQ ID NO. 17, and (2) LCDR1, a LCDR2, and a LCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a light variable region (VL) as set forth in SEQ ID NO. 16, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme.

In some embodiments, the PD-1 antibody comprises: (1) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 13 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 13, (2) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 14 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 14, (3) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 15 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 15, (4) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 10 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 10, (5) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 11 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 11, and (6) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 12 or an amino acid sequence with one or more substitutions as compared to SEQ ID No. 12.

In some embodiments, the PD-1 antibody comprises: (1) a heavy variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 17 or an amino acid sequence having at least 80%, 85%, 87%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity with SEQ ID NO. 17, and (2) a light variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 16 or an amino acid sequence having at least 80%, 85%, 87%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, or 99%identity with SEQ ID NO. 16.

Exemplary anti-PD-1 antibody can be used in the method of the present application includes but is not limited to polyclonal antibody, monoclonal antibody, Fab, scFv, diabody, triabody, minibody, VHH and sdAb. Exemplary anti-PD-1 antibody includes but is not limited to pidilizumab, cemiplimab, sintilimab, cetrelimab, spartalizumab, camrelizumab, tislelizumab, balstilimab, toripalimab, dostarlimab, ABBV-181, penpulimab, pembrolizumab, genolimzumab, retifanlimab, sasanlimab, AMP-224, AB122, F-520, MEDI-3387, MEDI-5771, MEDI-0680, SG-001, nivolumab, BCD-100, BAT-1306, BI-754091, CBT-501, GLS-010, LZM-009, Sym-021, CS-1003, HLX-10, AK-103, AM-0001, ENUM-244C8, ENUM-388D4, JTX-4014, RXI-762, STI-A1110, HLX-20, SSI-361, APL-501, TJ0141H, and SNA-01. In some embodiments, the anti-PD-1 antibody is toripalimab.

Method

In one aspect, provided is a method of treating solid tumor, comprising administering to a subject in need thereof a CD73 antibody or an antigen binding fragment thereof at a dosage of about 2 to about 50 mg/kg body weight. In some embodiments, the method comprises administering to a subject in need thereof the CD73 antibody at a dosage of about 10 to about 40 mg/kg body weight. In some embodiments, the method comprises administering to a subject in need thereof the CD73 antibody at a dosage of about 20 to about 40 mg/kg body weight. In some embodiments, the method comprises administering to a subject in need thereof the CD73 antibody at a dosage of about 25 to about 35 mg/kg body weight. In some embodiments, the method comprises administering to a subject in need thereof the CD73 antibody as described herein at a dosage of about 30 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 3 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 4 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 6 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 7 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 8 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 9 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 11 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 12 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 13 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 14 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 15 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 16 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 17 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 18 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated at a dosage of about 19 to about 20 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 11 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 9 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 8 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 7 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 6 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2 to about 5 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 11 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 9 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 8 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 7 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 6 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 3 to about 5 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 11 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 9 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 8 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 7 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 6 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 4 to about 5 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 11 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 9 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 8 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 7 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 5 to about 6 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 11 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 9 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 8 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 7 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 6 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 11 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 9 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 7 to about 8 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 11 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 10 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 8 to about 9 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 11 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 9 to about 10 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 12 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 11 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 13 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 11 to about 12 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 12 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 12 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 12 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 12 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 12 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 12 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 12 to about 14 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 12 to about 13 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 13 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 13 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 13 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 13 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 13 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 13 to about 15 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 13 to about 14 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 14 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 14 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 14 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 14 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 14 to about 16 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 14 to about 15 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 15 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 15 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 15 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 15 to about 17 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 15 to about 16 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 16 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 16 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 16 to about 18 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 16 to about 17 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 17 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 17 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 17 to about 18 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 18 to about 20 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 18 to about 19 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 19 to about 20 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 30 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 15to about 30 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 20 to about 30 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 25 to about 30 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 2, about 2.5, about 3, about 3.5, about 4, about 4.5, about 5, about 5.5, about 6, about 6.5, about 7, about 7.5, about 8, about 8.5, about 9, about 9.5, about 10, about 10.5, about 11, about 11.5, about 12, about 12.5, about 13, about 13.5, about 14, about 14.5, about 15, about 15.5, about 16, about 16.5, about 17, about 17.5, about 18, about 18.5, about 19, about 19.5, about 20 mg/kg, about 20.5, about 21, about 21.5, about 22, about 22.5, about 23, about 23.5, about 24, about 24.5, about 25, about 25.5, about 26, about 26.5, about 27, about 28.5, about 29, about 29.5, and about 30 mg/kg body weight. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 20 mg/kg body weight.

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administered to the subject once weekly (QW) , once every two weeks (Q2W) , once every three weeks (Q3W) , once every four weeks (Q4W) or once monthly. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject once every three weeks (Q3W) .

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dosage of 25-35, or 20 or 30 mg/kg once every three weeks (Q3W) .

In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject intravenously. In some embodiments, the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dosage of 20 or 30 mg/kg once every three weeks (Q3W) intravenously. In some embodiments, the CD73 antibody is uliledlimab, and the uliledlimab is administrated to the subject at a dosage of 20 or 30 mg/kg once every three weeks (Q3W) intravenously. In some embodiments, the CD73 antibody is oleclumab, and the oleclumab is administrated to the subject at a dosage of 20 or 30 mg/kg once every three weeks (Q3W) intravenously.

In some embodiments, the solid tumor is selected from the group consisting of acute lymphoid leukemia, multiple myeloma, glioma, mesothelial, ovarian cancer, sarcoma, cervical cancer, bladder cancer, breast cancer, colorectal cancer, endometrial cancer, esophageal cancer, head and neck cancer, kidney cancer, liver cancer, lung cancer, lymphoma, melanoma, skin cancer (basal cell cancer) , pancreatic cancer, prostate cancer, uterine cancer, and thyroid cancer. In some embodiments, the lung cancer comprises non-small cell lung cancer (NSCLC) and small lung cancer (SCLC) .

In some embodiments, the solid tumor is advanced solid tumor. In some embodiments, the solid tumor is metastatic solid tumor. In some embodiments, the solid tumor is refractory solid tumor. In some embodiments, the solid tumor is in stage III or stage IV.

In some embodiments, the method further comprises administrating a PD-1 antagonist to the subject. Any suitable PD-1 antagonist known to the art can be used in the present application.

In some embodiments, the PD-1 antagonist is a PD-1 antibody. In some embodiments, the PD-1 antagonist is a PD-1 antibody as described herein. In some embodiments, the PD-1 antibody is selected from the group consisting of pembrolizumab, nivolumab, toripalimab, pidilizumab, cemiplimab, sintilimab, cetrelimab, spartalizumab, camrelizumab, tislelizumab, balstilimab, dostarlimab, ABBV-181, penpulimab, genolimzumab, retifanlimab, sasanlimab, AMP-224, AB122, F-520, MEDI-3387, MEDI-5771, MEDI-0680, SG-001, BCD-100, BAT-1306, BI-754091, CBT-501, GLS-010, LZM-009, Sym-021, CS-1003, HLX-10, AK-103, AM-0001, ENUM-244C8, ENUM-388D4, JTX-4014, RXI-762, STI-A1110, HLX-20, SSI-361, APL-501, TJ0141H, and SNA-01. In some embodiments, the PD-1 antibody is Toripalimab.

In some embodiments, the PD-1 antibody is Toripalimab and is administrated to the subject at a dosage of 240 mg flat dose once every three weeks (Q3W) .

In some embodiments, the method comprises administrating to the subject uliledlimab at a dosage of 20 or 30 mg/kg once every three weeks (Q3W) and Toripalimab at a dosage of 240 mg flat dose once every three weeks (Q3W) , intravenously. In some embodiments, the method comprises administrating to the subject oleclumab at a dosage of 20 or 30 mg/kg once every three weeks (Q3W) and Toripalimab at a dosage of 240 mg flat dose once every three weeks (Q3W) , intravenously.

In some embodiments, the antibody or the antigen binding fragment thereof and the PD-1 antagonist are administrated concurrently. In some embodiments, the antibody or the antigen binding fragment thereof and the PD-1 antagonist are administrated separately.

In some embodiments, the method comprises intravenously administrating to the subject uliledlimab at a dosage of 20 or 30 mg/kg once every three weeks (Q3W) and Toripalimab at a dosage of 240 mg flat dose once every three weeks (Q3W) , concurrently. In some embodiments, the method comprises intravenously administrating to the subject oleclumab at a dosage of 20 or 30 mg/kg once every three weeks (Q3W) and Toripalimab at a dosage of 240 mg flat dose once every three weeks (Q3W) , concurrently.

In another aspect, provided herein is use of a CD73 antibody or an antigen binding fragment thereof in preparing a medicament for treating solid tumor in a subject in need thereof, wherein the medicament is administered to the subject at a dosage of about 2 to about 30 mg/kg body weight in combination with a PD-1 antagonist.

In some embodiments, a treatment method of the instant disclosure entails measuring the CD73 expression in a sample from the patient and administering the CD73 antibody or antigen binding fragment thereof if at least 40%of the tumor cells in the sample is positive in CD73 expression. In some embodiments, the method further entails measuring the PD-L1 expression in the sample.

In some embodiments, the subject is administered the CD73 antibody or antigen binding fragment thereof if at least 40%of the tumor cells are CD73 positive. In some embodiments, the subject is administered the CD73 antibody or antigen binding fragment thereof if at least 30%, 35%, 40%, 45%or 50%of the tumor cells are CD73 positive. In some embodiments, the subject is administered the CD73 antibody or antigen binding fragment thereof if at least 1%of the tumor cells are PD-L1 positive. In some embodiments, the subject is further administered a PD-l antagonist.

In some embodiments, the CD73 expression is protein expression of CD73. In some embodiments, the PD-L1 expression is protein expression of PD-L1. Any suitable method known in the art for determining or measuring the protein level can be used. In some embodiments, the method determines protein expressed on cell membrane. In some embodiments, the method determines level expressed in cytosol. In some embodiments, the method determines CD73 protein level expressed on cell membrane and in cytosol.

In some embodiments, the protein expression level is determined by immunohistochemistry (IHC) , which measures the amount of CD73 or PD-L1 protein in a cancer tissue sample, e.g., a NSCLC tissue sample. In some embodiments, the sample is a formalin fixed and/or paraffin embedded (FFPE) sample. In some embodiments, the sample is an archival sample. In some embodiments, the sample is a fresh sample. In some embodiments, the sample is a frozen sample. In some embodiments, the sample is obtained prior to the combination treatment as described herein.

In some embodiments of the method of the present application, in the IHC test, according to the staining intensity, the level of CD73 protein in each cell (including cell membrane and cytosol) can be assigned with an intensity of 0, 1, 2 or 3, based on the criteria as shown in Table 1.

Table 1. CD73 staining Criteria

In some embodiments, the IHC test determines the percentage of cells with staining intensities of 1, 2 and 3 relative to the total cells. In some embodiments, the cells include but are not limited to tumor cells, immune cells such as tumor infiltrating immune cells (TILs) , stromal cells, vessel cells and any combinations thereof.

In some embodiments, the IHC test determines the tumors with staining relative to the total tumor cells. In some embodiments, the IHC test determines the percentage of tumor cells with staining intensities of 1, 2 and 3 relative to the total tumor cells (TC) .

Article of Manufacture

In another aspect, provided herein is an article of manufacture, comprising: (1) a CD73 antibody or an antigen binding fragment thereof, and (2) a package insert which suggests administration of the CD73 antibody or the antigen binding fragment thereof to a subject in need thereof at a dosage of about 2 to about 20 mg/kg body weight in combination with a PD-1 antagonist. In some embodiments, the article of manufacture further comprises the PD-1 antagonist.

All publications and patent applications cited in this specification are herein incorporated by reference as if each individual publication or patent application were specifically and individually indicated to be incorporated by reference.

EXAMPLES

The following examples are put forth so as to provide those of ordinary skill in the art with a complete disclosure and description of how to make and use the present invention, and are not intended to limit the scope of what the inventors regard as their invention nor are they intended to represent that the experiments below are all or the only experiments performed. Efforts have been made to ensure accuracy with respect to numbers used (e.g. amounts, temperature, etc. ) but some experimental errors and deviations should be accounted for. Unless indicated otherwise, parts are parts by weight, molecular weight is weight average molecular weight, temperature is in degrees Centigrade, and pressure is at or near atmospheric.

Example 1. A Phase I/II Study of Uliledlimab for Advanced Solid Tumor

A dose-escalation and dose expansion phase I/II study was designed to evaluate the safety, pharmacokinetics (PK) , pharmacodynamics (PD) , and preliminary efficacy of Uliledlimab (ULI) alone, or in combination with Toripalimab (TOR) in patients with advanced solid tumor. ULI was administered iv. at 2, 5, or 10 mg/kg weekly (QW) or at 15, 20, or 30 mg/kg every 3 weeks (Q3W) alone, or in combination with TOR (240 mg, iv, Q3W) in dose escalation. Preliminary efficacy of ULI (20 mg/kg Q3W) + TOR (240 mg Q3W) was examined in non-small cell lung cancer (NSCLC) in dose expansion cohorts. Serum concentration of ULI and soluble CD73, CD73 receptor occupancy (RO) in circulating CD19+ B cells were detected. Tumor response was assessed by RECIST1.1/iRECIST.

A total of 92 patients were enrolled: 12 in dose escalation of ULI alone, 9 in ULI+TOR dose escalation group, and 71 in ULI+TOR dose expansion cohorts. ULI was well-tolerated with no DLT observed in dose escalation. Most of treatment-related adverse event (TRAE) were grade 1-2 with grade 3-4 TRAE occurring in 25%in ULI alone (2 patients with lymphocyte count decreased and 1 with transient QT prolongation) , and 13.8%in ULI+TOR group (most reported events were 2 patients each with hypotension and diarrhea) . Most common TRAE were grade 1-2 chills (47.8%) , vomiting (46.7%) , pyrexia (40.2%) , diarrhea (32.6%) , nausea (19.6%) , pruritus (14.1%) , rash (13%) that occurred after the first dose of ULI and resolved in subsequent infusions, which can be significantly reduced by steroid-based premedication. The PK of ULI was linear at doses ≥ 5 mg/kg and modelling indicated a mean derived effective t1/2 of 13.2 days. Soluble CD73 was undetectable and complete RO was maintained after the first dose at ≥ 15 mg/kg Q3W at Ctrough throughout the dosing interval. Among 48 efficacy-evaluable NSCLC patients in dose expansion cohorts, 6 partial responses (PR) (ORR 12.5%, 95%CI: 4.7%-25.2%) and 21 stable diseases (DCR 56.4%, 95%CI, 41.2%-70.5%) were observed. PRs were observed in 3 out of 8 systematic patients, and 3 out of 39 patients with relapse/refractory disease to previous systematic treatment including 2 patients received no prior PD- (L) 1 inhibitor treatment and 1 patient failed.

ULI was safe and tolerated up to 30 mg/kg Q3W. Linear PK was observed at doses ≥5 mg/kg with t1/2 of 13.2 days. Full saturation of circulating and cell-bound CD73 was maintained at doses ≥ 15 mg/kg Q3W. ULI combined with TOR exhibited evidence of anti-tumor activity in NSCLC patients.

Example 2. Pharmacokinetic Profile of Uliledlimab

This example conducted a pharmacokinetic (PK) analysis in a trial enrolling NSCLC patients. ULI doses included 2 mg/kg (QW) , 5 mg/kg (QW) , 10 mg/kg (QW) , 15 mg/kg (Q3W) , 20 mg/kg (Q3W) , and 30 mg/kg (Q3W) .

At doses of 5 mg/kg weekly or above, ULI exhibited a linear PK profile, indicating target saturation. The associated receptor occupancy (RO) data and ≥ 80%of maximum CD73 inhibition in tumor cell lines with reasonably assumed 10%tumor penetration rate were used to estimate a target concentration of 80 μg/mL for ULI to reach at C_trough concentrations to expect sufficient target inhibition.

Simulation of ULI in humans based on a population PK model established upon clinical PK data (FIG. 1) shows that sufficient tumor target engagement can be expected when C_trough concentration reaches 80 ug/mL. Accordingly, 30 mg/kg Q3W (with an additional dose at cycle 1 day 8 (C1D8) is considered a suitable dosing regimen for ULI.

To confirm the CD73 receptor occupancy and inhibition of CD73 enzymatic activity by ULI in tumors at the selected dose of 30 mg/kg Q3W, tumor biopsies from two NSCLC patients treated with 30 mg/kg ULI were collected at C_trough timepoint C3D1 or C4D1. The expression of total CD73 in tumor, including the ones bounded by ULI, was determined by immunohistochemical (IHC) staining using an anti-CD73 antibody not competing with ULI (FIG. 2A and 2D) ; while the expression of free CD73 that was not bound by ULI was determined by IHC staining using an anti-CD73 competing with ULI (FIG. 2B and 2E) . In addition, residual CD73 enzymatic activity in tumor was measured by enzyme-histochemistry (EHC) staining (FIG. 2C and 2F) . At the dose of 30 mg/kg Q3W, ULI saturated CD73 occupancy, leading to the complete inhibition of CD73 enzyme activity in the tumor even at C_trough.

Example 3. CD73 Expression Level Correlates to Response

This example evaluated the CD73 expression levels in the tumors and their correlation to patient response to treatment with ULI in combination with Toripalimab (TOR) .

Patients were classified generally to a CD73-high group and a CD73-low group based on IHC staining of the tumor samples at baseline. Clinical responses were measured as objective response rate (ORR) and disease control rate (DCR) per iRECIST criteria.

To identify a suitable CD73 cutoff level in predicting the clinical response, a receiver operating characteristic (ROC) curve analysis was conducted among all treated patients (n=45) . The ROC curve is presented in FIG. 3, based on which a 40%cutoff value was selected. Here, the 40%value means 40%of tumor or immune cells were stained with CD73 antibody (staining intensity can be any of 1 (nominal) , 2 (moderate) , or 3 (intense) ) .

As shown in Table 1, CD73-high patients had significantly better response to the treatment than CD73-low patients.

Table 1. CD73 Expression and Response

When the CD73 level was combined with PD-L1 expression level, their ability to classify patients to high and low response groups was further improved. For instance, as shown in FIG. 4, the improved clinical response in CD73-high patients compared to CD73-low patients is more prominent in both PD-L1 1-49%group and PD-L1 ≥ 50%groups, compared to PD-L1 <1%group.

The present invention has been described in terms of particular embodiments found or proposed by the present inventor to comprise preferred modes for the practice of the invention. It will be appreciated by those of skill in the art that, in light of the present disclosure, numerous modifications and changes can be made in the particular embodiments exemplified without departing from the intended scope of the invention. For example, due to codon redundancy, changes can be made in the underlying DNA sequence without affecting the protein sequence. Moreover, due to biological functional equivalency considerations, changes can be made in protein structure without affecting the biological action in kind or amount. All such modifications are intended to be included within the scope of the appended claims.

SEQUENCE LISTING

Claims

A method of treating solid tumor, comprising administering to a subject in need thereof a CD73 antibody or an antigen binding fragment thereof at a dosage of about 2 to about 60 mg/kg body weight and a PD-1 antagonist.
The method of claim 1, wherein the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 10 to about 40 mg/kg body weight.
The method of claim 1, wherein the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 25 to about 35 mg/kg body weight.
The method of claim 1, wherein the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dose of about 30 mg/kg body weight.
The method of any one of claims 1-4, wherein the CD73 antibody or the antigen binding fragment thereof is administered to the subject once weekly (QW) , once every two weeks (Q2W) , once every three weeks (Q3W) , once every four weeks (Q4W) or once monthly.
The method of any one of claims 1-5, wherein the CD73 antibody or the antigen binding fragment thereof is administrated to the subject once every three weeks (Q3W) .
The method of any one of claims 1-6, wherein the CD73 antibody or the antigen binding fragment thereof is administrated to the subject at a dosage of 25 or 35 mg/kg once every three weeks (Q3W) .
The method of any one of claims 1-7, wherein the CD73 antibody or the antigen binding fragment thereof is administrated to the subject intravenously.
The method of any one of claims 1-8, wherein the CD73 antibody or the antigen binding fragment thereof is selected from a group consisting of a full-length antibody, Fab, Fab’, F (ab’) 2, scFv, and sdAb.
The method of claim 9, wherein the CD73 antibody or the antigen binding fragment thereof is a full-length antibody.
The method of any one of claims 1-10, wherein the CD73 antibody or the antigen binding fragment thereof comprises a HCDR1, a HCDR2, and a HCDR3, respectively comprising the amino acid sequences of a CDR1, a CDR2, and a CDR3 within a heavy variable region (VH) as set forth in SEQ ID NO. 1, wherein the CDR1, CDR2, and CDR3 are according to Kabat numbering scheme.
The method of any one of claims 1-11, wherein the CD73 antibody or the antigen binding fragment thereof comprises:

(1) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 3,

(2) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 4,

(3) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 5,

(4) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 6,

(5) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 7, and

(6) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 8.
The method of any one of claims 1-12, wherein the CD73 antibody or the antigen binding fragment thereof comprises a heavy variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 1 and a light variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 2.
The method of any one of claims 1-13, wherein the CD73 antibody or the antigen binding fragment thereof is selected from the group consisting of uliledlimab (I-Mab Biopharma) , oleclumab (AstraZeneca) , CPI-006 (Corvus Pharma) , BMS-986179 (Bristol-Myers Squibb) , AB-680 (Arcus Biosciences) , NZV-930 (SRF373, Surface Oncolohgy/Novartis) , JAB-BX102 (Jacobio) , AK119 (Akesobio) , Sym024 (Symphogen) , IBI 325 (Innovent) , BR 101 (Hisun BioRay) , and LY3475070 (Eli-Lilly) .
The method of any one of claims 1-14, wherein the solid tumor is selected from the group consisting of ovarian cancer, sarcoma, cervical cancer, bladder cancer, breast cancer, colorectal cancer, endometrial cancer, esophageal cancer, head and neck cancer, kidney cancer, liver cancer, lung cancer, lymphoma, acute lymphoid leukemia, multiple myeloma, glioma, mesothelial, melanoma, skin cancer (basal cell cancer) , pancreatic cancer, prostate cancer, uterine cancer, and thyroid cancer.
The method of any one of claims 1-15, wherein the lung cancer comprises non-small cell lung cancer (NSCLC) and small lung cancer (SCLC) .
The method of any one of claims 1-16, wherein the solid tumor is advanced solid tumor.
The method of any one of claims 1-17, wherein the solid tumor is metastatic solid tumor.
The method of any one of claims 1-18, wherein the solid tumor is relapsed solid tumor.
The method of any one of claims 1-19, wherein the solid tumor is refractory solid tumor.
The method of any one of claims 1-20, wherein the solid tumor is in stage III or stage IV.
The method of any one of claims 1-21, wherein the CD73 antibody or the antigen binding fragment thereof and the PD-1 antagonist are administrated concurrently.
The method of any one of claims 1-21, wherein the CD73 antibody or the antigen binding fragment thereof and the PD-1 antagonist are administrated separately.
The method of claim 1-23, wherein the PD-1 antagonist is a PD-1 antibody.
The method of claim 24, wherein the PD-1 antibody comprises:

(1) a LCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 10,

(2) a LCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 11,

(3) a LCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 12,

(4) a HCDR1 comprising an amino acid sequence as set forth in SEQ ID No. 13,

(5) a HCDR2 comprising an amino acid sequence as set forth in SEQ ID No. 14, and

(6) a HCDR3 comprising an amino acid sequence as set forth in SEQ ID No. 15.
The method of 24 or 25, wherein the PD-1 antibody comprises:

(1) a heavy variable region (VL) comprising an amino acid sequence as set forth in SEQ ID NO. 16 or an amino acid sequence having at least 90%identity with SEQ ID NO. 16, and

(2) a light variable region (VH) comprising an amino acid sequence as set forth in SEQ ID NO. 17 or an amino acid sequence having at least 90%identity with SEQ ID NO. 17.
The method of claim 24, wherein the PD-1 antibody is selected from the group consisting of pembrolizumab, nivolumab, toripalimab, pidilizumab, cemiplimab, sintilimab, cetrelimab, spartalizumab, camrelizumab, tislelizumab, balstilimab, dostarlimab, ABBV-181, penpulimab, genolimzumab, retifanlimab, sasanlimab, AMP-224, AB122, F-520, MEDI-3387, MEDI-5771, MEDI-0680, SG-001, BCD-100, BAT-1306, BI-754091, CBT-501, GLS-010, LZM-009, Sym-021, CS-1003, HLX-10, AK-103, AM-0001, ENUM-244C8, ENUM-388D4, JTX-4014, RXI-762, STI-A1110, HLX-20, SSI-361, APL-501, TJ0141H, and SNA-01.
The method of claim 27, wherein the PD-1 antibody is Toripalimab.
The method of claim 28, wherein the PD-1 antibody is administrated to the subject at a dosage of 240 mg flat dose once every three weeks (Q3W) .
The method of any one of claims 1-29, wherein the subject has a tumor tissue in which at least 40%of the tumor cells are CD73 positive.
The method of any one of claims 1-29, wherein the subject has a tumor tissue in which at least 30%, 35%, 40%, 45%or 50%of the tumor cells are CD73 positive.
The method of claim 30 or 31, wherein the at least 1%of the tumor cells are PD-L1 positive.
Use of a CD73 antibody or an antigen binding fragment thereof in preparing a medicament for treating solid tumor in a subject in need thereof, wherein the medicament is administered to the subject at a dosage of about 2 to about 60 mg/kg body weight in combination with a PD-1 antagonist.
An article of manufacture, comprising:

(1) a CD73 antibody or an antigen binding fragment thereof, and

(2) a package insert which suggests administration of the CD73 antibody or the antigen binding fragment thereof to a subject in need thereof at a dosage of about 2 to about 60 mg/kg body weight in combination with a PD-1 antagonist.
The article of manufacture of claim 34 further comprising the PD-1 antagonist.