WO2023241659A1

WO2023241659A1 - Methods of treating lymphoma using anti-tigit antibodies

Info

Publication number: WO2023241659A1
Application number: PCT/CN2023/100462
Authority: WO
Inventors: Xiaotong Li
Original assignee: Beigene, Ltd.
Priority date: 2022-06-16
Filing date: 2023-06-15
Publication date: 2023-12-21

Abstract

Provided are methods of treating diffuse large B-cell lymphoma (DLBCL) or increasing, enhancing, or stimulating an immune response with antibodies that specifically bind to TIGIT (T cell immunoreceptor with Ig and ITIM domains) and antigen-binding fragments thereof in combination with an anti-PD1 antibody and/or an anti-CD20 antibody.

Description

METHODS OF TREATING LYMPHOMA USING ANTI-TIGIT ANTIBODIES

FIELD

The present application relates to antibodies that specifically bind to TIGIT (T cell immunoreceptor with Ig and ITIM domains) in combination with anti-PD1 antibodies and/or anti-CD20 antibodies for the treatment of lymphoma such as diffuse large B cell lymphoma (DLCBL) .

BACKGROUND

TIGIT (T cell immunoglobulin and ITIM domain) is a type I transmembrane protein, a member of the CD28 family of proteins that plays an important role in inhibiting T-and NK cell-mediated functional activities in anti-tumor immunity (Boles KS, et al., 2009 Eur J Immunol, 39: 695-703; Stanietsky N, et al., 2009 PNAS 106: 17858-63; Yu X, et al. 2009 Nat. Immunol, 10: 48-57) .

The genes and cDNAs coding for TIGIT were cloned and characterized in mouse and human. Full length human TIGIT has a sequence of 244 amino acids (SEQ ID NO: 1) in length, in which the first 21 amino acids consist of a signal peptide. The amino acid sequence of the mature human TIGIT contains 223 amino acid (aa) residues (NCBI accession number: NM_173799) . The extracellular domain (ECD) of mature human TIGIT consists of 120 amino acid residues (SEQ ID NO: 2, corresponding to amino acids 22-141 of SEQ ID NO: 1) with a V-type Ig-like domain (corresponding to amino acids 39-127 of SEQ ID NO: 1) , followed by a 21 aa transmembrane sequence, and an 82 aa cytoplasmic domain with an immunoreceptor tyrosine-based inhibitory motif (ITIM) (Yu X, et al. 2009 Nat. Immunol, 10: 48-57; Stengel KF, et al. 2012 PNAS 109: 5399-04) . Within the ECD, human TIGIT shares only 59%and 87%aa sequence identity with mouse and cynomolgus monkey, respectively.

Monoclonal antibodies that target either PD1 or PD-L1, can block this interaction and boost the immune response against cancer cells. These antibodies have been shown to be helpful in treating several types of cancer, including melanoma of the skin, non-small cell lung cancer (NSCLC) , kidney cancer, bladder cancer, head and neck cancers, and Hodgkin lymphoma. Cancer cells in most non-responders to single-agent checkpoint inhibitors escape through innate mechanisms that allow the cancer cells to grow and survive. As a result, disease progresses at a rate consistent with the natural history. However, unlike intrinsic resistance, late relapses are now emerging in patients with prior clinical benefit after longer follow-up of clinical trials, suggesting the emergence of acquired resistance (Jenkins et al., Br. J. Cancer 118, 9-16 2018) .

Anti-CD20 antibodies, for example, rituximab can be responsible for rapidly killing tumor targets via FcγR mediated ADCC or antibody dependent cellular phagocytosis (ADCP) , a short-term process mediated by natural killer cells and myeloid effector cells from innate immune system (Taylor and Lindorfer, Curr Opin Immunol. 2008; 20 (4) : 444-449; Minard-Colin et al., Blood. 2008; 112 (4) : 1205-1213) . Studies also reveal that the therapeutic function and long-term immune memory of anti-CD20 antibodies require active crosstalk with adaptive immunity. Evidence in lymphoma patients suggests that rituximab can induce a strong antitumor vaccinal effect by priming antitumor T cell responses, resulting in durable response (Cartron et al., Blood. 2004; 104 (9) : 2635-2642) . Using a murine lymphoma model to express human CD20, CD4+ and CD8+ T cells are demonstrated to be required for anti CD20 mAb mediated long term memory immune response (Abes et al., Blood. 2010; 116 (6) : 926-934) , and the mechanism of anti-CD20 antibodies was shown to engage the macrophage for immediate ADCC and dendritic cells for long term antitumor cellular immune response (DiLillo et al., Cell. 2015; 161 (5) : 1035-1045) .

Diffuse large B-cell lymphoma (DLBCL) is an aggressive and heterogeneous disease with a variable clinical outcome (Susanibar-Adaniya et al., Am J Hematol. 2021; 96 (5) : 617-629. ) and is the most common subtype of aggressive non-Hodgkin lymphomas (NHL) in the Western Countries, accounting for around 31%of NHL cases in adults. There were 544, 352 new cases of NHL and 259, 793 deaths resulting from this disease worldwide in 2020 (Sung et al., CA Cancer J Clin. 2021; 71 (3) : 209-249) . The incidence rate for DLBCL is approximately 6.9 cases per 100,000 person-years (Teras et al., CA Cancer J Clin. 2016 Nov 12; 66 (6) : 443-459) . Based on the study report of National Central Cancer Registry of China, an estimated of 88, 200 new lymphoma cases and 52, 100 lymphoma deaths occurred in China in 2015, ranked in the 12th and 11th place among all cancer cases, respectively (Chen et al., CA Cancer J Clin. 2016; 66 (2) : 115-132) . Two locally retrospective studies for NHL distributions in China showed that DLBCL made up about 29.1%and 40.9%of NHL, respectively (Liu et al., Asian Pac J Cancer Prev. 2011; 12 (11) : 3055-3061; Gross et al., China. Int J Hematol. 2008; 88 (2) : 165-173) . According to the current Surveillance Epidemiology and End Results (SEER) data, the median age at diagnosis is 66 years (SEER 2020) . Therefore, the combination of anti-TIGIT antibodies in combination with anti-PD1 antibodies can rescue immune cells from tolerance, inducing efficient immune responses in the treatment of cancer or chronic viral infections.

SUMMARY OF THE INVENTION

The present disclosure is directed methods of diffuse large B-cell lymphoma (DLBCL) treatment, administering anti-TIGIT antibodies in combination with anti-PD1 antibodies and/or anti-CD20 antibodies.

A method of diffuse large B-cell lymphoma (DLBCL) treatment, the method comprising administering to a subject an effective amount of an anti-TIGIT antibody or antigen-binding fragment thereof in combination with an effective amount of an anti-PD1 antibody or antigen binding fragment thereof.

The method, wherein the method comprises administering to a subject an effective amount of an antibody or antigen-binding fragment thereof, which specifically binds to human TIGIT and comprises: a heavy chain variable region that comprises a HCDR (Heavy Chain Complementarity Determining Region) 1 of SEQ ID NO: 1, a HCDR2 of SEQ ID NO: 2, and a HCDR3 of SEQ ID NO: 3; and a light chain variable region that comprises a LCDR (Light Chain Complementarity Determining Region) 1 of SEQ ID NO: 4, a LCDR2 of SEQ ID NO: 5, and a LCDR3 of SEQ ID NO: 6.

The method, wherein the anti-TIGIT antibody or antigen-binding fragment thereof comprises: a heavy chain variable region (VH) that comprises SEQ ID NO: 7, and a light chain variable region (VL) that comprises SEQ ID NO: 8.

The method, wherein the anti-PD1 antibody comprises an antibody or an antigen binding fragment thereof which specifically binds human PD1, and comprises: a heavy chain variable region that comprises: a HCDR1 of SEQ ID NO: 12, HCDR2 of SEQ ID NO: 13, and HCDR3 of SEQ ID NO: 14; and a light chain variable region that comprises LCDR1 of SEQ ID NO: 15, LCDR2 of SEQ ID NO: 16, and LCDR3 of SEQ ID NO: 17.

The method, wherein the anti-PD1 antibody or antigen binding fragment thereof which specifically binds human PD1 and comprises a heavy chain variable region (VH) comprising an amino acid sequence of SEQ ID NO: 18 and a light chain variable region (VL) comprising an amino acid sequence of SEQ ID NO: 19.

The method wherein the anti-PD1 antibody comprises an IgG4 constant domain comprising SEQ ID NO: 20.

The method wherein the anti-TIGIT antibody is an antibody fragment selected from the group consisting of Fab, Fab'-SH, Fv, scFv, and (Fab') 2 fragments.

The method wherein the anti-PD1 antibody is an antibody fragment selected from the group consisting of Fab, Fab'-SH, Fv, scFv, and (Fab') 2 fragments.

A method of diffuse large B-cell lymphoma (DLBCL) treatment, the method comprising administering to a subject an effective amount of an anti-TIGIT antibody or antigen-binding fragment thereof in combination with an effective amount of an anti-CD20 antibody or antigen binding fragment thereof.

The method wherein the method comprises administering to a subject an effective amount of an antibody or antigen-binding fragment thereof, which specifically binds to human TIGIT and comprises: a heavy chain variable region that comprises a HCDR (Heavy Chain Complementarity Determining Region) 1 of SEQ ID NO: 1, a HCDR2 of SEQ ID NO: 2, and a HCDR3 of SEQ ID NO: 3; and a light chain variable region that comprises a LCDR (Light Chain Complementarity Determining Region) 1 of SEQ ID NO: 4, a LCDR2 of SEQ ID NO: 5, and a LCDR3 of SEQ ID NO: 6.

The method wherein the anti-TIGIT antibody or antigen-binding fragment thereof comprises: a heavy chain variable region (VH) that comprises SEQ ID NO: 7, and a light chain variable region (VL) that comprises SEQ ID NO: 8.

The method wherein the anti-CD20 antibody is Rituximab (Rituxan) , Britumomab (Zevalin) , Tositumomab (Bexxar) or Obinutuzumab (Gazyva) .

The method wherein the anti-CD20 antibody is Rituximab (Rituxan) .

The method wherein the DLBCL is relapsed or refractory DLBCL.

The method further comprising the administration of chemotherapy.

The method wherein the chemotherapy is cyclophosphamide, doxorubicin, vincristine, and prednisone.

The method wherein the anti-PD1 antibody is dosed at 200mg every three weeks.

The method wherein the anti-TIGIT antibody is dosed at a range of 50mg-900mg.

The method wherein the anti-TIGIT antibody is dosed at 50 mg every three weeks.

The method wherein the anti-TIGIT antibody is dosed at 150 mg every three weeks.

The method wherein the anti-TIGIT antibody is dosed at 450 mg every three weeks.

The method wherein the anti-TIGIT antibody is dosed at 900 mg every three weeks.

The method wherein Rituximab is administered at 375 mg/m².

A method of diffuse large B-cell lymphoma (DLBCL) treatment, the method comprising administering to a subject an effective amount of an anti-TIGIT antibody or antigen-binding fragment thereof in combination with an effective amount of an anti-CD20 antibody or antigen binding fragment thereof and an effective amount of an anti-PD1 antibody.

The method wherein the anti-PD1 antibody comprises an antibody or an antigen binding fragment thereof which specifically binds human PD1, and comprises: a heavy chain variable region that comprises: a HCDR1 of SEQ ID NO: 12, HCDR2 of SEQ ID NO: 13, and HCDR3 of SEQ ID NO: 14; and a light chain variable region that comprises LCDR1 of SEQ ID NO: 15, LCDR2 of SEQ ID NO: 16, and LCDR3 of SEQ ID NO: 17.

The method wherein the anti-PD1 antibody or antigen binding fragment thereof which specifically binds human PD1 and comprises a heavy chain variable region (VH) comprising an amino acid sequence of SEQ ID NO: 18 and a light chain variable region (VL) comprising an amino acid sequence of SEQ ID NO: 19.

The method further comprising the administration of chemotherapy.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a graphical representation of the therapeutics, their dosages and cohorts

DETAILED DESCRIPTION

Definitions

Conservative amino acid substitutions of amino acids are commonly known in the art and exemplarily shown in the table below. Generally, a conservative amino acid substitution means that an amino acid residue is replaced by another amino acid residue having a similar side chain.

Unless specifically defined elsewhere in this document, all other technical and scientific terms used herein have the meaning commonly understood by one of ordinary skill in the art to which this invention belongs.

As used herein, including the appended claims, the singular forms of words such as “a, ” “an, ” and “the” include their corresponding plural references unless the context clearly dictates otherwise.

The term “or” is used to mean, and is used interchangeably with, the term “and/or” unless the context clearly dictates otherwise.

Throughout this specification and the claims which follow, unless the context requires otherwise, the word "comprise" , and variations such as "comprises" and "comprising" , will be understood to imply the inclusion of a stated amino acid sequence, DNA sequence, step or group thereof, but not the exclusion of any other amino acid sequence, DNA sequence, step. When used herein the term "comprising" can be substituted with the term "containing" , “including” or sometimes "having. "

The term “TIGIT” includes various mammalian isoforms, e.g., human TIGIT, orthologs of human TIGIT, and analogs comprising at least one epitope within TIGIT. The amino acid sequence of TIGIT, e.g., human TIGIT, and the nucleotide sequence encoding the same, is known in the art (see Genbank AAI01289) .

“PD1” or “Programmed cell death protein 1” is a receptor that delivers inhibitory signals upon binding to ligands CD274/PD-L1 and CD273/PD-L2. The amino acid sequence of human PD1 is known in the art and can be found at accession number NP_005009 (Genbank) .

The term “CD-20” or “B-lymphocyte surface antigen B1” is a B-lymphocyte-specific membrane protein that aids in the regulation of cellular calcium influx. The amino acid of CD20 is set forth in Genbank accession number NP_068769.

The terms “administration, ” “administering, ” “treating” and “treatment” as used herein, when applied to an animal, human, experimental subject, cell, tissue, organ, or biological fluid, mean contact of an exogenous pharmaceutical, therapeutic, diagnostic agent, or composition to the animal, human, subject, cell, tissue, organ, or biological fluid. Treatment of a cell encompasses contact of a reagent to the cell, as well as contact of a reagent to a fluid, where the fluid is in contact with the cell. The term “administration” or “treatment” also includes in vitro and ex vivo treatments, e.g., of a cell, by a reagent, diagnostic, binding compound, or by another cell. The term “subject” herein refers to any organism, preferably an animal, more preferably a mammal (e.g., rat, mouse, dog, cat, rabbit) and most preferably a human.

The term “antibody” herein is used in the broadest sense and specifically covers antibodies (including full length monoclonal antibodies) and antibody fragments so long as they recognize antigen, e.g., TIGIT. An antibody is usually monospecific, but may also be described as idiospecific, heterospecific, or polyspecific. Antibody molecules bind by means of specific binding sites to specific antigenic determinants or epitopes on antigens.

The term “monoclonal antibody” or “mAb” or “Mab” herein means a population of substantially homogeneous antibodies, i.e., the antibody molecules comprised in the population are identical in amino acid sequence except for possible naturally occurring mutations that may be present in minor amounts. In contrast, conventional (polyclonal) antibody preparations typically include a multitude of different antibodies having different amino acid sequences in their variable domains, particularly their complementarity determining regions (CDRs) , which are often specific for different epitopes. 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. Monoclonal antibodies (mAbs) may be obtained by methods known to those skilled in the art. See, for example Kohler G et al., Nature 1975 256: 495-497; U.S. Pat. No. 4,376,110; Ausubel FM et al., CURRENT PROTOCOLS IN MOLECULAR BIOLOGY 1992; Harlow E et al., ANTIBODIES: A LABORATORY MANUAL, Cold spring Harbor Laboratory 1988; and Colligan JE et al., CURRENT PROTOCOLS IN IMMUNOLOGY 1993. The mAbs disclosed herein may be of any immunoglobulin class including IgG, IgM, IgD, IgE, IgA, and any subclass thereof. A hybridoma producing a mAb may be cultivated in vitro or in vivo. High titers of mAbs can be obtained by in vivo production where cells from the individual hybridomas are injected intraperitoneally into mice, such as pristine-primed Balb/c mice to produce ascites fluid containing high concentrations of the desired mAbs. MAbs of isotype IgM or IgG may be purified from such ascites fluids, or from culture supernatants, using column chromatography methods well known to those of skill in the art.

In general, the basic antibody structural unit comprises a tetramer. Each tetramer includes two identical pairs of polypeptide chains, each pair having one “light chain” (about 25 kDa) and one “heavy chain” (about 50-70 kDa) . The amino-terminal portion of each chain includes a variable region of about 100 to 110 or more amino acids primarily responsible for antigen recognition. The carboxy-terminal portion of the heavy chain may define a constant region primarily responsible for effector function. Typically, human light chains are classified as kappa and lambda light chains. Furthermore, human heavy chains are typically classified as α, δ, ε, γ, or μ, and define the antibody's isotypes as IgA, IgD, IgE, IgG, and IgM, respectively. Within light and heavy chains, the variable and constant regions are joined by a “J” region of about 12 or more amino acids, with the heavy chain also including a “D” region of about 10 more amino acids.

The variable regions of each light/heavy chain (VL/VH) pair form the antibody binding site. Thus, in general, an intact antibody has two binding sites. Except in bifunctional or bispecific antibodies, the two binding sites are, in general, the same.

Typically, the variable domains of both the heavy and light chains comprise three hypervariable regions, also called “complementarity determining regions (CDRs) ” , which are located between relatively conserved framework regions (FR) . The CDRs are usually aligned by the framework regions, enabling binding to a specific epitope. In general, from N-terminal to C-terminal, both light and heavy chain variable domains sequentially comprise FR-1 (or FR1) , CDR-1 (or CDR1) , FR-2 (FR2) , CDR-2 (CDR2) , FR-3 (or FR3) , CDR-3 (CDR3) , and FR-4 (or FR4) . The assignment of amino acids to each domain is, generally, in accordance with the definitions of Sequences of Proteins of Immunological Interest, Kabat, et al., National Institutes of Health, Bethesda, Md.; 5th ed.; NIH Publ. No. 91-3242 (1991) ; Kabat (1978) Adv. Prot. Chem. 32: 1-75; Kabat, et al., (1977) J. Biol. Chem. 252: 6609-6616; Chothia, et al, (1987) J Mol. Biol. 196: 901-917 or Chothia, et al., (1989) Nature 342: 878-883.

The term “hypervariable region” means the amino acid residues of an antibody that are responsible for antigen-binding. The hypervariable region comprises amino acid residues from a “CDR” (i.e., VL-CDR1, VL-CDR2 and VL-CDR3 in the light chain variable domain and VH-CDR1, VH-CDR2 and VH-CDR3 in the heavy chain variable domain) . See, Kabat et al. (1991) Sequences of Proteins of Immunological Interest, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md. (defining the CDR regions of an antibody by sequence) ; see also Chothia and Lesk (1987) J. Mol. Biol. 196: 901-917 (defining the CDR regions of an antibody by structure) . The term “framework” or “FR” residues mean those variable domain residues other than the hypervariable region residues defined herein as CDR residues.

Unless otherwise indicated, “antibody fragment” or “antigen-binding fragment” means antigen binding fragments of antibodies, i.e., antibody fragments that retain the ability to bind specifically to the antigen bound by the full-length antibody, e.g., fragments that retain one or more CDR regions. Examples of antigen binding fragments include, but not limited to, Fab, Fab', F (ab') 2, and Fv fragments; diabodies; linear antibodies; single-chain antibody molecules, e.g., single chain Fv (ScFv) ; nanobodies and multispecific antibodies formed from antibody fragments.

An antibody that binds to a specified target protein with specificity is also described as specifically binding to a specified target protein. This means the antibody exhibits preferential binding to that target as compared to other proteins, but this specificity does not require absolute binding specificity. An antibody is considered “specific” for its intended target if its binding is determinative of the presence of the target protein in a sample, e.g., without producing undesired results such as false positives. Antibodies or binding fragments thereof, useful in the present invention will bind to the target protein with an affinity that is at least two-fold greater, preferably at least 10-times greater, more preferably at least 20-times greater, and most preferably at least 100-times greater than the affinity with non-target proteins. An antibody herein is said to bind specifically to a polypeptide comprising a given amino acid sequence, e.g., the amino acid sequence of a mature human TIGIT molecule, if it binds to polypeptides comprising that sequence but does not bind to proteins lacking that sequence.

The expressions “pH-dependent binding” , “pH-dependent target binding” and “pH-dependent antigen binding” are interchangeable in the present disclosure, indicating that the antibody of the present application binds to its target/antigen, namely human TIGIT, in a pH-dependent manner. Specifically, the antibody of the present application shows a higher binding affinity and/or binding signal to its antigen at a mild acidic pH, e.g., pH 6.0, which is usually found in tumor microenvironment, as compared to the binding affinity and/or binding signal at physiologic pH, e.g., pH 7.4. The methods for determining the binding affinity and/or the intensity of binding signal of the antibody of the present application are well known in the art and include but not limited to surface plasmon resonance (Biacore) or similar technology. More specifically, the antibody of the present application has a K_D ratio at pH 7.4/pH 6.0 of greater than 2, 3, 4, 5, 6, 7, 8, 9, 10, 20, 30, 40, 50, 60, 70, 80, 90, 100, or more, as measured by surface plasmon resonance (Biacore) or similar technology. Alternatively, or additionally, the antibody of the present application has a Rmax (RU) value at pH 6.0 which is at least 2-fold, 3-fold, 4-fold, 5-fold, 6-fold, 7-fold, 8-fold, 9-fold, 10-fold, 20-fold, 30-fold, 40-fold, 50-fold higher than the Rmax at pH 7.4 as measured by surface plasmon resonance (Biacore) or similar technology. The binding affinity of the antibody can be measured at 25℃ or 37℃. Tumor microenvironment has been found to show a relatively more acidic pH than physiological condition or normal tissues. Therefore, the antibody of the present application having above-mentioned pH-dependent binding is advantageous as an anti-TIGIT therapeutic agent for targeting TIGIT-positive lymphocytes in the tumor microenvironment with selectivity and having lower toxicity associated with periphery activation of lymphocytes.

The term “human antibody” herein means an antibody that comprises human immunoglobulin protein sequences only. A human antibody may contain murine carbohydrate chains if produced in a mouse, in a mouse cell, or in a hybridoma derived from a mouse cell. Similarly, “mouse antibody” or “rat antibody” means an antibody that comprises only mouse or rat immunoglobulin protein sequences, respectively.

The term “humanized antibody” means forms of antibodies that contain sequences from non-human (e.g., murine) antibodies as well as human antibodies. Such antibodies contain minimal sequence derived from non-human immunoglobulin. In general, the humanized antibody will comprise substantially all of at least one, and typically two, variable domains, in which all or substantially all of the hypervariable loops correspond to those of a non-human immunoglobulin and all or substantially all of the FR regions are those of a human immunoglobulin sequence. The humanized antibody optionally also will comprise at least a portion of an immunoglobulin constant region (Fc) , typically that of a human immunoglobulin. The prefix “hum, ” “hu, ” “Hu” or “h” is added to antibody clone designations when necessary to distinguish humanized antibodies from parental rodent antibodies. The humanized forms of rodent antibodies will generally comprise the same CDR sequences of the parental rodent antibodies, although certain amino acid substitutions may be included to increase affinity, increase stability of the humanized antibody, or for other reasons.

The antibody of the present application has potential therapeutic uses in treating cancer. The term “cancer” or “tumor” herein means or describes the physiological condition in mammals that is typically characterized by unregulated cell growth. Examples of cancer include but are not limited to, leukemia, lymphoma, diffuse large B-cell lymphoma (DLBCL) and relapsed or refractory DLBCL.

Further, the antibody of the present application has potential therapeutic uses in controlling viral infections and other human diseases that are mechanistically involved in immune tolerance or ″exhaustion. ” In the context of the present application, the term “exhaustion” refers to a process which leads to a depleted ability of immune cells to respond during to a cancer or a chronic viral infection.

The term “therapeutically effective amount” as herein used, refers to the amount of an antibody that, when administered to a subject for treating a disease or a disorder, or at least one of the clinical symptoms of a disease or disorder, is sufficient to affect such treatment for the disease, disorder, or symptom. The “therapeutically effective amount” can vary with the antibody, the disease, disorder, and/or symptoms of the disease or disorder, severity of the disease, disorder, and/or symptoms of the disease or disorder, the age of the subject to be treated, and/or the weight of the subject to be treated. An appropriate amount in any given instance can be apparent to those skilled in the art or can be determined by routine experiments. In the case of combination therapy, the “therapeutically effective amount” refers to the total amount of the active agents comprised in the combination for the effective treatment of a disease, a disorder or a condition.

The “subject” as used herein is a mammal, e.g., a rodent or a primate, preferably a higher primate, e.g., a human (e.g., a patient having, or at risk of having, a disorder described herein) .

Anti-TIGIT antibodies

The present disclosure provides for antibodies, antigen-binding fragments, that specifically bind human TIGIT. Furthermore, the present disclosure provides antibodies that have desirable pharmacokinetic characteristics and other desirable attributes, and thus can be used for the treatment of lymphoma, for example, DLBCL. The present disclosure further provides pharmaceutical compositions comprising the antibodies and methods of making and using such pharmaceutical compositions for the prevention and treatment of DLBCL and associated disorders.

The present disclosure provides for antibodies or antigen-binding fragments thereof that specifically bind to TIGIT. Anti-TIGIT antibodies are also provided herein and comprise, for example, a heavy chain variable region (VH) comprising the complementarity determining regions (CDRs) : HCDR1 as set forth in SEQ ID NO: 1 , HCDR2 as set forth in SEQ ID NO: 2, and HCDR3 as set forth in SEQ ID NO: 3; and a light chain variable region (VL) comprising: LCDR1 as set forth in SEQ ID NO: 4, LCDR2 as set forth in SEQ ID NO: 5, and LCDR3 as set forth in SEQ ID NO: 6. Antibodies or antigen-binding fragments of the present disclosure include, but are not limited to, the antibodies or antigen-binding fragments thereof, as described in Table 1 below, which is designated “BGB-A1217” or “Ociperlimab. ”

Table 1

Anti-PD1 antibodies

PD1 antibodies are also provided herein and comprise, for example, a heavy chain variable region (VH) comprising the complementarity determining regions (CDRs) : HCDR1 as set forth in SEQ ID NO: 12 , HCDR2 as set forth in SEQ ID NO: 13, and HCDR3 as set forth in SEQ ID NO: 14; and a light chain variable region (VL) comprising: LCDR1 as set forth in SEQ ID NO: 15, LCDR2 as set forth in SEQ ID NO: 16, and LCDR3 as set forth in SEQ ID NO: 17. This antibody is designated herein as “BGB-A317” or “Tislelizumab” and the sequences of this antibody are set forth in Table 2.

Table 2

Further Alteration of the Framework of Fc Region

In yet other aspects, the Fc region is altered by replacing at least one amino acid residue with a different amino acid residue to alter the effector functions of the antibody. For example, one or more amino acids can be replaced with a different amino acid residue such that the antibody has an altered affinity for an effector ligand but retains the antigen-binding ability of the parent antibody. The effector ligand to which affinity is altered can be, for example, an Fc receptor or the C1 component of complement. This approach is described in, e.g., U.S. Pat. Nos. 5,624,821 and 5,648,260, both by Winter et al.

In another aspect, one or more amino acid residues can be replaced with one or more different amino acid residues such that the antibody has altered C1q binding and/or reduced or abolished complement dependent cytotoxicity (CDC) . This approach is described in, e.g., U.S. Pat. No. 6,194,551 by Idusogie et al.

In yet another aspect, one or more amino acid residues are altered to thereby alter the ability of the antibody to fix complement. This approach is described in, e.g., the PCT Publication WO 94/29351 by Bodmer et al. In a specific aspect, one or more amino acids of an antibody or antigen-binding fragment thereof of the present disclosure are replaced by one or more allotypic amino acid residues, for the IgG1 subclass and the kappa isotype. Allotypic amino acid residues also include, but are not limited to, the constant region of the heavy chain of the IgG1, IgG2, and IgG3 subclasses as well as the constant region of the light chain of the kappa isotype as described by Jefferis et al., MAbs. 1: 332-338 (2009) .

In another aspect, the Fc region is modified to increase the ability of the antibody to mediate antibody dependent cellular cytotoxicity (ADCC) and/or to increase the affinity of the antibody for an Fcγreceptor by modifying one or more amino acids. This approach is described in, e.g., the PCT Publication WO 00/42072 by Presta. Moreover, the binding sites on human IgG1 for FcγRI, FcγRII, FcγRIII and FcRn have been mapped and variants with improved binding have been described (see Shields et al., J. Biol. Chem. 276: 6591-6604, 2001) .

In still another aspect, the glycosylation of an antibody is modified. For example, an aglycosylated antibody can be made (i.e., the antibody lacks or has reduced glycosylation) . Glycosylation can be altered to, for example, increase the affinity of the antibody for “antigen. ” Such carbohydrate modifications can be accomplished by, for example, altering one or more sites of glycosylation within the antibody sequence. For example, one or more amino acid substitutions can be made that result in elimination of one or more variable region framework glycosylation sites to thereby eliminate glycosylation at that site. Such aglycosylation can increase the affinity of the antibody for antigen. Such an approach is described in, e.g., U.S. Pat. Nos. 5,714,350 and 6,350,861 by Co et al.

Additionally, or alternatively, an antibody can be made that has an altered type of glycosylation, such as a hypofucosylated antibody having reduced amounts of fucosyl residues or an antibody having increased bisecting GlcNac structures. Such altered glycosylation patterns have been demonstrated to increase the ADCC ability of antibodies. Such carbohydrate modifications can be accomplished by, for example, expressing the antibody in a host cell with altered glycosylation machinery. Cells with altered glycosylation machinery have been described in the art and can be used as host cells in which to express recombinant antibodies to thereby produce an antibody with altered glycosylation. For example, EP 1,176,195 by Hang et al. describes a cell line with a functionally disrupted FUT8 gene, which encodes a fucosyl transferase, such that antibodies expressed in such a cell line exhibit hypofucosylation. PCT Publication WO 03/035835 by Presta describes a variant CHO cell line, Lecl3 cells, with reduced ability to attach fucose to Asn (297) -linked carbohydrates, also resulting in hypofucosylation of antibodies expressed in that host cell (see also Shields et al., (2002) J. Biol. Chem. 277: 26733-26740) . PCT Publication WO 99/54342 by Umana et al., describes cell lines engineered to express glycoprotein-modifying glycosyl transferases (e.g., beta (1, 4) -N acetylglucosaminyltransferase III (GnTIII) ) such that antibodies expressed in the engineered cell lines exhibit increased bisecting GlcNac structures which results in increased ADCC activity of the antibodies (see also Umana et al., Nat. Biotech. 17: 176-180, 1999) .

In another aspect, if a reduction of ADCC is desired, human antibody subclass IgG4 was shown in many previous reports to have only modest ADCC and almost no CDC effector function (Moore G L, et al. 2010 MAbs, 2: 181-189) . On the other hand, natural IgG4 was found less stable in stress conditions such as in acidic buffer or under increasing temperature (Angal, S. 1993 Mol Immunol, 30: 105-108; Dall'A cqua, W. et al, 1998 Biochemistry, 37: 9266-9273; Aalberse et al. 2002 Immunol, 105: 9-19) . Reduced ADCC can be achieved by operably linking the antibody to IgG4 engineered with combinations of alterations to have reduced or null FcγR binding or C1q binding activities, thereby reducing or eliminating ADCC and CDC effector functions. Considering physicochemical properties of antibody as a biological drug, one of the less desirable, intrinsic properties of IgG4 is dynamic separation of its two heavy chains in solution to form half antibody, which lead to bi-specific antibodies generated in vivo via a process called “Fab arm exchange” (Van der Neut Kolfschoten M, et al. 2007 Science, 317: 1554-157) . The mutation of serine to proline at position 228 (EU numbering system) appeared inhibitory to the IgG4 heavy chain separation (Angal, S. 1993 Mol Immunol, 30: 105-108; Aalberse et al. 2002 Immunol, 105: 9-19) . Some of the amino acid residues in the hinge and γFc region were reported to have impact on antibody interaction with Fcγ receptors (Chappel S M, et al. 1991 Proc. Natl. Acad. Sci. USA, 88: 9036-9040; Mukherjee, J. et al., 1995 FASEB J, 9: 115-119; Armour, K.L. et al. 1999 Eur J Immunol, 29: 2613-2624; Clynes, R. A. et al, 2000 Nature Medicine, 6: 443-446; Arnold J.N., 2007 Annu Rev immunol, 25: 21-50) . Furthermore, some rarely occurring IgG4 isoforms in human population can also elicit different physicochemical properties (Brusco, A. et al. 1998 Eur J Immunogenet, 25: 349-55; Aalberse et al. 2002 Immunol, 105: 9-19) .

Antibody Production

Ociperlimab and Tislelizumab antibodies and antigen-binding fragments thereof can be produced by any means known in the art, including but not limited to, recombinant expression, chemical synthesis, and enzymatic digestion of antibody tetramers, whereas full-length monoclonal antibodies can be obtained by, e.g., hybridoma or recombinant production. Recombinant expression can be from any appropriate host cells known in the art, for example, mammalian host cells, bacterial host cells, yeast host cells, insect host cells, etc.

The disclosure further provides polynucleotides encoding the antibodies described herein, e.g., polynucleotides encoding heavy or light chain variable regions or segments comprising the complementarity determining regions as described herein. In some aspects, the polynucleotide encoding the heavy chain variable regions has at least 85%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%nucleic acid sequence identity with a polynucleotide that encodes for the polypeptides of Table 1 or Table 2. In some aspects, the polynucleotide encoding the light chain variable regions has at least 85%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%nucleic acid sequence identity with a polynucleotide that encodes for the polypeptides of Table 1 or Table 2.

Also provided in the present disclosure are expression vectors and host cells for producing Ociperlimab and/or Tislelizumab antibodies. The choice of expression vector depends on the intended host cells in which the vector is to be expressed. Typically, the expression vectors contain a promoter and other regulatory sequences (e.g., enhancers) that are operably linked to the polynucleotides encoding an Ociperlimab and/or Tislelizumab antibody chain or antigen-binding fragment. In some aspects, an inducible promoter is employed to prevent expression of inserted sequences except under the control of inducing conditions. Inducible promoters include, e.g., arabinose, lacZ, metallothionein promoter or a heat shock promoter. Cultures of transformed organisms can be expanded under non-inducing conditions without biasing the population for coding sequences whose expression products are better tolerated by the host cells. In addition to promoters, other regulatory elements can also be required or desired for efficient expression of an Ociperlimab and/or Tislelizumab antibody or antigen-binding fragment. These elements typically include an ATG initiation codon and adjacent ribosome binding site or other sequences. In addition, the efficiency of expression can be enhanced by the inclusion of enhancers appropriate to the cell system in use (see, e.g., Scharf et al., Results Probl. Cell Differ. 20: 125, 1994; and Bittner et al., Meth. Enzymol., 153: 516, 1987) . For example, the SV40 enhancer or CMV enhancer can be used to increase expression in mammalian host cells.

The host cells for harboring and expressing the Ociperlimab and/or Tislelizumab antibody chains can be either prokaryotic or eukaryotic. E. coli is one prokaryotic host useful for cloning and expressing the polynucleotides of the present disclosure. Other microbial hosts suitable for use include bacilli, such as Bacillus subtilis, and other enterobacteriaceae, such as Salmonella, Serratia, and various Pseudomonas species. In these prokaryotic hosts, one can also make expression vectors, which typically contain expression control sequences compatible with the host cell (e.g., an origin of replication) . In addition, any number of a variety of well-known promoters will be present, such as the lactose promoter system, a tryptophan (trp) promoter system, a beta-lactamase promoter system, or a promoter system from phage lambda. The promoters typically control expression, optionally with an operator sequence, and have ribosome binding site sequences and the like, for initiating and completing transcription and translation. Other microbes, such as yeast, can also be employed to express Ociperlimab and/or Tislelizumab polypeptides. Insect cells in combination with baculovirus vectors can also be used.

In other aspects, mammalian host cells are used to express and produce the Ociperlimab and/or Tislelizumab polypeptides of the present disclosure. For example, they can be either a hybridoma cell line expressing endogenous immunoglobulin genes or a mammalian cell line harboring an exogenous expression vector. These include any normal mortal or normal or abnormal immortal animal or human cell. For example, a number of suitable host cell lines capable of secreting intact immunoglobulins have been developed, including the CHO cell lines, various COS cell lines, HEK 293 cells, myeloma cell lines, transformed B-cells and hybridomas. The use of mammalian tissue cell culture to express polypeptides is discussed generally in, e.g., Winnacker, From Genes to Clones, VCH Publishers, NY, N.Y., 1987. Expression vectors for mammalian host cells can include expression control sequences, such as an origin of replication, a promoter, and an enhancer (see, e.g., Queen et al., Immunol. Rev. 89: 49-68, 1986) , and necessary processing information sites, such as ribosome binding sites, RNA splice sites, polyadenylation sites, and transcriptional terminator sequences. These expression vectors usually contain promoters derived from mammalian genes or from mammalian viruses. Suitable promoters can be constitutive, cell type-specific, stage-specific, and/or modulatable or regulatable. Useful promoters include, but are not limited to, the metallothionein promoter, the constitutive adenovirus major late promoter, the dexamethasone-inducible MMTV promoter, the SV40 promoter, the MRP polIII promoter, the constitutive MPSV promoter, the tetracycline-inducible CMV promoter (such as the human immediate-early CMV promoter) , the constitutive CMV promoter, and promoter-enhancer combinations known in the art.

Methods of Detection and Diagnosis

The antibodies or antigen-binding fragments of the present disclosure are useful in a variety of applications including, but not limited to, methods for the detection of TIGIT. In one aspect, the antibodies or antigen-binding fragments are useful for detecting the presence of TIGIT in a biological sample. The term “detecting” as used herein includes quantitative or qualitative detection. In certain aspects, a biological sample comprises a cell or tissue. In other aspects, such tissues include normal and/or cancerous tissues that express TIGIT at higher levels relative to other tissues.

In one aspect, the present disclosure provides a method of detecting the presence of TIGIT in a biological sample. In certain aspects, the method comprises contacting the biological sample with an anti-TIGIT antibody under conditions permissive for binding of the antibody to the antigen and detecting whether a complex is formed between the antibody and the antigen. The biological sample can include, without limitation, urine or blood samples.

Also included is a method of diagnosing a disorder associated with expression of TIGIT. In certain aspects, the method comprises contacting a test cell with an anti-TIGIT antibody; determining the level of expression (either quantitatively or qualitatively) of TIGIT in the test cell by detecting binding of the anti-TIGIT antibody to the TIGIT polypeptide; and comparing the level of expression in the test cell with the level of TIGIT expression in a control cell (e.g., a normal cell of the same tissue origin as the test cell or a non-TIGIT expressing cell) , wherein a higher level of TIGIT expression in the test cell as compared to the control cell indicates the presence of a disorder associated with expression of TIGIT.

Methods of Treatment

The antibodies or antigen-binding fragments of the present disclosure are useful in a variety of applications including, but not limited to, methods for the treatment of an TIGIT-associated disorder or disease. In one aspect, the TIGIT-associated disorder or disease is lymphoma and in certain aspects is DLBCL or refractory or relapsed DLBCL.

In one aspect, the present disclosure provides a method of treating cancer. In certain aspects, the method comprises administering to a patient in need an effective amount of an anti-TIGIT antibody or antigen-binding fragment. The cancer can include, without limitation, lymphoma, leukemia, DLBCL and refractory or relapsed DLBCL.

An antibody or antigen-binding fragment of the invention can be administered by any suitable means, including parenteral, intrapulmonary, and intranasal, and, if desired for local treatment, intralesional administration. Parenteral infusions include intramuscular, intravenous, intraarterial, intraperitoneal, or subcutaneous administration. Dosing can be by any suitable route, e.g., by injections, such as intravenous or subcutaneous injections, depending in part on whether the administration is brief or chronic. Various dosing schedules including but not limited to single or multiple administrations over various time-points, bolus administration, and pulse infusion are contemplated herein.

Antibodies or antigen-binding fragments of the invention would be formulated, dosed, and administered in a fashion consistent with good medical practice. Factors for consideration in this context include the particular disorder being treated, the particular mammal being treated, the clinical condition of the individual patient, the cause of the disorder, the site of delivery of the agent, the method of administration, the scheduling of administration, and other factors known to medical practitioners. The antibody need not be but is optionally formulated with one or more agents currently used to prevent or treat the disorder in question. The effective amount of such other agents depends on the amount of antibody present in the formulation, the type of disorder or treatment, and other factors discussed above. These are generally used in the same dosages and with administration routes as described herein, or about from 1 to 99%of the dosages described herein, or in any dosage and by any route that is empirically/clinically determined to be appropriate.

For the prevention or treatment of disease, the appropriate dosage of an antibody or antigen- binding fragment of the invention will depend on the type of disease to be treated, the type of antibody, the severity and course of the disease, whether the antibody is administered for preventive or therapeutic purposes, previous therapy, the patient's clinical history and response to the antibody, and the discretion of the attending physician. The antibody is suitably administered to the patient at one time or over a series of treatments. Depending on the type and severity of the disease, about 1 μg/kg to 100 mg/kg of antibody can be an initial candidate dosage for administration to the patient, whether, for example, by one or more separate administrations, or by continuous infusion. One typical daily dosage might range from about 1 μg/kg to 100 mg/kg or more, depending on the factors mentioned above. For repeated administrations over several days or longer, depending on the condition, the treatment would generally be sustained until a desired suppression of disease symptoms occurs. Such doses can be administered intermittently, e.g., every week or every three weeks (e.g., such that the patient receives from about two to about twenty, or e.g., about six doses of the antibody) . An initial higher loading dose, followed by one or more lower doses can be administered. However, other dosage regimens can be useful. The progress of this therapy is easily monitored by conventional techniques and assays.

Combination Therapy

In one aspect, Ociperlimab antibodies can be used in combination with other therapeutic agents, for example anti-PD1 antibodies. Anti-PD1 antibodies can include, without limitation, Tislelizumab as described above. Pembrolizumab (formerly MK-3475) , as disclosed by Merck, is a humanized lgG4-K immunoglobulin with a molecular weight of about 149 kDa, which targets the PD1 receptor and inhibits binding of the PD1 receptor ligands PD-L1 and PD-L2. Pembrolizumab has been approved for the indications of metastatic melanoma and metastatic non-small cell lung cancer (NSCLC) and is under clinical investigation for the treatment of head and neck squamous cell carcinoma (HNSCC) , and refractory Hodgkin's lymphoma (cHL) . Nivolumab (as disclosed by Bristol-Meyers Squibb is a fully human lgG4-K monoclonal antibody. Nivolumab (clone 5C4) is disclosed in US Patent No. US 8,008, 449 and WO 2006/121 168. Nivolumab is approved for the treatment of melanoma, lung cancer, kidney cancer, and Hodgkin's lymphoma.

In another aspect, Ociperlimab antibodies can be used with anti-CD20 antibodies, which can include, without limitation, Rituximab (Rituxan) , Britumomab (Zevalin) , Tositumomab (Bexxar) and Obinutuzumab (Gazyva) . Anti-CD20 antibodies, for example, Rituximab is directed against the CD20 antigen expressed on the surface of pre-B and mature B-lymphocytes. Upon binding to CD20, these antibodies mediate B-cell lysis, with possible mechanisms of lysis including complement-dependent cytotoxicity (CDC) and ADCC. Most common adverse events associated with Rituximab (≥ 25%) in clinical trials for NHL were infusion reaction, fever, lymphopenia, chills, infection, and asthenia. Tumor lysis syndrome (TLS) can be associated with Rituximab treatment in patients with NHL, with a high number of circulating malignant cells (≥ 25,000/mm³) or high tumor burden conferring a greater risk of TLS. Rituximab is currently approved for treatment of CD20⁺ NHL, including CD20⁺ DLBCL.

Another combination for the treatment of DLBCL includes the administration of Ociperlimab, Tislelizumab and/or Rituximab with the current treatments for DLBCL. The addition of Rituximab to a chemotherapy regimen of cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) has significantly improved the clinical outcome (Coiffier et al., N Engl J Med. 2002; 346 (4) : 235-242) . Recently, the Phase III POLARIX study comparing polatuzumab vedotin in combination with chemotherapy regimen R-CHP versus the standard of care R-CHOP in treatment of first line DLBCL met its primary endpoint by demonstrating significantly improved and clinically meaningful progression free survival. However, 30%to 40%of patients with DLBCL eventually relapse and 10%of them are primary refractory, which remains as a consistent clinical problem (Flowers et al., CA Cancer J Clin. 2010; 60 (6) : 393-408) . Thus, the combination of Ociperlimab, Tislelizumab and/or Rituximab with the administration of chemotherapy can prove useful in the treatment of DLBCL and refractory or relapsed DLBCL.

Pharmaceutical compositions and formulations

Also provided are compositions, including pharmaceutical formulations, comprising an anti-TIGIT antibody or antigen-binding fragment, or polynucleotides comprising sequences encoding an anti-TIGIT antibody or antigen-binding fragment. In certain embodiments, compositions comprise one or more antibodies or antigen-binding fragments that bind to TIGIT, or one or more polynucleotides comprising sequences encoding one or more antibodies or antigen-binding fragments that bind to TIGIT. These compositions can further comprise suitable carriers, such as pharmaceutically acceptable excipients including buffers, which are well known in the art.

Pharmaceutical formulations of an TIGIT antibody or antigen-binding fragment as described herein are prepared by mixing such antibody or antigen-binding fragment having the desired degree of purity with one or more optional pharmaceutically acceptable carriers (Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. (1980) ) , in the form of lyophilized formulations or aqueous solutions. Pharmaceutically acceptable carriers are generally nontoxic to recipients at the dosages and concentrations employed, and include, but are not limited to: buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid and methionine; preservatives (such as octadecyldimethylbenzyl ammonium chloride; hexamethonium chloride; benzalkonium chloride; benzethonium chloride; phenol, butyl or benzyl alcohol; alkyl parabens such as methyl or propyl paraben; catechol; resorcinol; cyclohexanol; 3-pentanol; and m-cresol) ; low molecular weight (less than about 10 residues) polypeptides; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, histidine, arginine, or lysine; monosaccharides, disaccharides, and other carbohydrates including glucose, mannose, or dextrins; chelating agents such as EDTA; sugars such as sucrose, mannitol, trehalose or sorbitol; salt-forming counter-ions such as sodium; metal complexes (e.g. Zn-protein complexes) ; and/or non-ionic surfactants such as polyethylene glycol (PEG) . Exemplary pharmaceutically acceptable carriers herein further include interstitial drug dispersion agents such as soluble neutral-active hyaluronidase glycoproteins (sHASEGP) , for example, human soluble PH-20 hyaluronidase glycoproteins, such as rHuPH20 (Baxter International, Inc. ) . Certain exemplary sHASEGPs and methods of use, including rHuPH20, are described in US Patent Nos. US 7,871,607 and 2006/0104968. In one aspect, a sHASEGP is combined with one or more additional glycosaminoglycanases such as chondroitinases.

Exemplary lyophilized antibody formulations are described in US Patent No. 6,267,958. Aqueous antibody formulations include those described in US Patent No. 6,171,586 and WO2006/044908, the latter formulations including a histidine-acetate buffer.

Sustained-release preparations can be prepared. Suitable examples of sustained-release preparations include semipermeable matrices of solid hydrophobic polymers containing the antibody, which matrices are in the form of shaped articles, e.g., films, or microcapsules.

The formulations to be used for in vivo administration are generally sterile. Sterility can be readily accomplished, e.g., by filtration through sterile filtration membranes.

Pharmaceutical Compositions and Kits

In some aspects, this disclosure provides compositions, e.g., pharmaceutically acceptable compositions, which include an anti-TIGIT antibody described herein, formulated together with at least one pharmaceutically acceptable excipient. As used herein, the term “pharmaceutically acceptable excipient” includes any and all solvents, dispersion media, isotonic and absorption delaying agents, and the like that are physiologically compatible. The excipient can be suitable for intravenous, intramuscular, subcutaneous, parenteral, rectal, spinal or epidermal administration (e.g., by injection or infusion) .

The compositions herein may be in a variety of forms. These include, for example, liquid, semi-solid and solid dosage forms, such as liquid solutions (e.g., injectable and infusion solutions) , dispersions or suspensions, liposomes, and suppositories. A suitable form depends on the intended mode of administration and therapeutic application. Typical suitable compositions are in the form of injectable or infusion solutions. One suitable mode of administration is parenteral (e.g., intravenous, subcutaneous, intraperitoneal, intramuscular) . In some embodiments, the antibody is administered by intravenous infusion or injection. In certain embodiments, the antibody is administered by intramuscular or subcutaneous injection.

EXAMPLE

Example 1: Ociperlimab and Tislelizumab in the treatment of DLBCL

TIGIT and PD1 function as immune checkpoint receptors in the overlapping regulation of immune tolerance. Blockade of the TIGIT receptor alone or in combination with PD1/PD-L1 blockade has been shown both in vitro and in vivo to rescue functionally “exhausted” T-cells (Chauvin et al., J Clin Invest. 2015; 125: 2046-58) . In mouse models, TIGIT blockade in combination with anti-PD1/PD-L1 antibodies demonstrated significantly better antitumor efficacy than either monotherapy (Dixon et al., J Immunol. 2018; 200: 3000-7) . Clinically, treatment with Ociperlimab in combination with Tislelizumab has the potential to be more effective than Tislelizumab alone in DLBCL without prior checkpoint inhibitor therapy.

For example, the combination of tiragolumab plus atezolizumab reported an overall response rate of 31%and a progression free survival of 5.42 months versus placebo plus atezolizumab with an overall response rate of 16%and a progression free survival of 3.58 months in first-line Stage IV NSCLC patients with PD-L1 Tumor Proportion Score ≥ 1% (Rodriguez-Abreu et al., J Clin Oncol. 2020; 38 (suppl 15): 9503) . Similarly, the vibostolimab plus pembrolizumab combination reported an unconfirmed and confirmed ORR of 29%and 24%, respectively, in patients with NSCLC who were untreated or had been treated with at least 1 line of platinum-containing chemotherapy and had not previously received anti-PD1/PD-L1 therapy (Niu et al., Annals of Oncology 2020; 31: S891-2) .

Gene expression analysis has previously verified upregulation of TIGIT and PD-L1 in DLBCL compared with normal controls (Laurent et al., 2015; 4 (8) : e1026530) . Characterization of coinhibitory receptor expression in intratumoral T cells from DLBCL revealed that both TIGIT and PD1 were expressed at higher frequency than all other receptors such asTIM-3 and LAG-3. The co-expression pattern of TIGIT and PD1 not only contributes to impaired T-cell effector function as tested by cytokine production, but also inhibits the antitumor activity of T cell through interaction with ligand-expressing tumor cells in DLBCL (CD155 and CD122 expression) . All these indicate the value of combinatorial blockade of TIGIT and PD1 in DLBCL and exploration for mechanisms of immune escape by characterizing the tumor microenvironment (Josefsson et al., Cancer Immunol Res. 2019; 7 (3) : 355-362) .

However, the limitation of single agent of anti-PD1 is also observed in patients with R/R DLBCL, with the overall response rate of approximately 10%. A trend of increasing overall response rate and complete response rate was observed in patients with high PD-L1 expression on the surface of tumor cells in a combination therapy of nivolumab and ibrutinib. Given the tolerable and manageable safety profile of Tislelizumab in DLBCL and the scientific rationale of synergistic antitumor effects between anti-TIGIT and anti-PD1 therapies, the combination of Ociperlimab and Tislelizumab can bring significant clinical benefit in R/R DLBCL in PD-L1 positive patients and supports further clinical development.

Safety and efficacy data of Tislelizumab in NHL (including DLBCL) are available from one ongoing combination therapy study. A Phase 1b, open label, multiple-dose, dose-escalation, and dose expansion study of Zanubrutinib in combination with Tislelizumab in patients with B-cell lymphoid malignancies (i.e., NHL) is currently on-going.

For patients that are PD-L1 positive, they will be relegated to Cohort 1 -Cohort 1: DLBCL or R/R DLBCL patients with positive PD-L1 on the surface of tumor cells (with any expression level) will receive Ociperlimab in combination with Tislelizumab. Approximately 43 to 50 patients will be recruited for Cohort 1. Patients will receive a treatment cycle of 21 days. The combination of Ociperlimab with Tislelizumab will be administrated intravenously on Day 1 of each 21-day cycle continuously. Ociperlimab 900 mg in combination with Tislelizumab 200 mg will be administered on Day 1 of each 3-week cycle.

Example 2: Ociperlimab and Rituximab in the treatment of DLBCL

To ensure the maximum clinical benefit for DLBCL patients that are PD-L1 negative, Rituximab will be administered in combination with Ociperlimab, in either DLBCL or refractory/relapsed (R/R) DLBCL patients. Ociperlimab will synergize with Rituximab by enhancing T cell/NK-cell activation and Treg depletion/inhibition to promote both immediate tumor killing and long term memory immune response.

The study will determine the preliminary antitumor activity of Ociperlimab in combination with Tislelizumab or Rituximab in patients with DLBCL or R/R DLBCL (Figure 1) . As described above, eligible patients will be allocated to 2 cohorts based on PD-L1 expression level on the surface of tumor cells, which can be tested at local laboratory by immunohistochemistry IHC. Those patients that are PD-L1 negative will be assigned to Cohort 2-Cohort 2: DLBCL or R/R DLBCL patients with negative PD-L1 on the surface of tumor cells will receive Ociperlimab in combination with Rituximab.

Approximately 23 to 30 patients in Cohort 2 will be enrolled in the entire study. Every treatment cycle contains 21 days. The combination of Ociperlimab with Rituximab in Cohort 2 will be administrated intravenously on Day 1 of each 21-day cycle continuously. Ociperlimab will be tested at the dose level of 900mg initially. If Ociperlimab 900mg exceeds the MTD, Ociperlimab 600 mg will be tested. Other dose levels of Ociperlimab (e.g., lower than 600 mg) may be explored to confirm the optimal dose level of Ociperlimab in combination with Rituximab. The dose of Rituximab will be administered at 375 mg/m².

Example 3: Ociperlimab, Tislelizumab and Rituximab in the treatment of DLBCL

For DLBCL or R/R DLBCL patients that are PD-L1 positive, the administration of Ociperlimab, Tislelizumab, Rituximab and chemotherapy will be explored. TIGIT blockade by Ociperlimab has the potential to promote NK cell activation against poliovirus receptor+ (PVR+) tumor cells and to synergize the therapeutic monoclonal antibodies (such as Rituximab) mediated ADCC activity. Combining this with the ability of Tislelizumab to rescue functionally “exhausted” T cells and the chemotherapy when R-CHOP is indicated (cyclophosphamide, hydroxydaunorubicin hydrochloride (doxorubicin hydrochloride) , vincristine (Oncovin) and prednisone) , this combination can have the ability to address aggressive forms of DLBCL or R/R DLBCL.

Claims

A method of diffuse large B-cell lymphoma (DLBCL) treatment, the method comprising administering to a subject an effective amount of an anti-TIGIT antibody or antigen-binding fragment thereof in combination with an effective amount of an anti-PD1 antibody or antigen binding fragment thereof.
The method of claim 1, wherein the method comprises administering to a subject an effective amount of an antibody or antigen-binding fragment thereof, which specifically binds to human TIGIT and comprises: a heavy chain variable region that comprises a HCDR (Heavy Chain Complementarity Determining Region) 1 of SEQ ID NO: 1, a HCDR2 of SEQ ID NO: 2, and a HCDR3 of SEQ ID NO: 3; and a light chain variable region that comprises a LCDR (Light Chain Complementarity Determining Region) 1 of SEQ ID NO: 4, a LCDR2 of SEQ ID NO: 5, and a LCDR3 of SEQ ID NO: 6.
The method of claim 2, wherein the anti-TIGIT antibody or antigen-binding fragment thereof comprises: a heavy chain variable region (VH) that comprises SEQ ID NO: 7, and a light chain variable region (VL) that comprises SEQ ID NO: 8.
The method of claim 1, wherein the anti-PD1 antibody comprises an antibody or an antigen binding fragment thereof which specifically binds human PD1, and comprises:

a heavy chain variable region that comprises: a HCDR1 of SEQ ID NO: 12, HCDR2 of SEQ ID NO: 13, and HCDR3 of SEQ ID NO: 14; and a light chain variable region that comprises LCDR1 of SEQ ID NO: 15, LCDR2 of SEQ ID NO: 16, and LCDR3 of SEQ ID NO: 17.
The method of claim 4, wherein the anti-PD1 antibody or antigen binding fragment thereof which specifically binds human PD1 and comprises a heavy chain variable region (VH) comprising an amino acid sequence of SEQ ID NO: 18 and a light chain variable region (VL) comprising an amino acid sequence of SEQ ID NO: 19.
The method of claim 4 or 5 wherein the anti-PD1 antibody comprises an IgG4 constant domain comprising SEQ ID NO: 20.
The method of claim 1, wherein the anti-TIGIT antibody is an antibody fragment selected from the group consisting of Fab, Fab'-SH, Fv, scFv, and (Fab') 2 fragments.
The method of claim 1, wherein the anti-PD1 antibody is an antibody fragment selected from the group consisting of Fab, Fab'-SH, Fv, scFv, and (Fab') 2 fragments.
A method of diffuse large B-cell lymphoma (DLBCL) treatment, the method comprising administering to a subject an effective amount of an anti-TIGIT antibody or antigen-binding fragment thereof in combination with an effective amount of an anti-CD20 antibody or antigen binding fragment thereof.
The method of claim 9, wherein the method comprises administering to a subject an effective amount of an antibody or antigen-binding fragment thereof, which specifically binds to human TIGIT and comprises: a heavy chain variable region that comprises a HCDR (Heavy Chain Complementarity Determining Region) 1 of SEQ ID NO: 1, a HCDR2 of SEQ ID NO: 2, and a HCDR3 of SEQ ID NO: 3; and a light chain variable region that comprises a LCDR (Light Chain Complementarity Determining Region) 1 of SEQ ID NO: 4, a LCDR2 of SEQ ID NO: 5, and a LCDR3 of SEQ ID NO: 6.
The method of claim 10, wherein the anti-TIGIT antibody or antigen-binding fragment thereof comprises: a heavy chain variable region (VH) that comprises SEQ ID NO: 7, and a light chain variable region (VL) that comprises SEQ ID NO: 8.
The method of claim 9, wherein the anti-CD20 antibody is Rituximab (Rituxan) , Britumomab (Zevalin) , Tositumomab (Bexxar) or Obinutuzumab (Gazyva) .
The method of claim 12, wherein the anti-CD20 antibody is Rituximab (Rituxan) .
The method of claim 1 or claim 9, wherein the DLBCL is relapsed or refractory DLBCL.
The method of claim 1 or claim 9 further comprising the administration of chemotherapy.
The method of claim 15, wherein the chemotherapy is cyclophosphamide, doxorubicin, vincristine, and prednisone.
The method of claim 1, wherein the anti-PD1 antibody is dosed at 200mg every three weeks.
The method of claim 1, wherein the anti-TIGIT antibody is dosed at a range of 50mg-900mg.
The method of claim 1, wherein the anti-TIGIT antibody is dosed at 50 mg every three weeks.
The method of claim 1, wherein the anti-TIGIT antibody is dosed at 150 mg every three weeks.
The method of claim 1, wherein the anti-TIGIT antibody is dosed at 450 mg every three weeks.
The method of claim 1, wherein the anti-TIGIT antibody is dosed at 900 mg every three weeks.
The method of claim 13, wherein Rituxan is administered at 375 mg/m².
A method of diffuse large B-cell lymphoma (DLBCL) treatment, the method comprising administering to a subject an effective amount of an anti-TIGIT antibody or antigen-binding fragment thereof in combination with an effective amount of an anti-CD20 antibody or antigen binding fragment thereof and an effective amount of an anti-PD1 antibody.
The method of claim 24, wherein the method comprises administering to a subject an effective amount of an antibody or antigen-binding fragment thereof, which specifically binds to human TIGIT and comprises: a heavy chain variable region that comprises a HCDR (Heavy Chain Complementarity Determining Region) 1 of SEQ ID NO: 1, a HCDR2 of SEQ ID NO: 2, and a HCDR3 of SEQ ID NO: 3; and a light chain variable region that comprises a LCDR (Light Chain Complementarity Determining Region) 1 of SEQ ID NO: 4, a LCDR2 of SEQ ID NO: 5, and a LCDR3 of SEQ ID NO: 6.
The method of claim 25, wherein the anti-TIGIT antibody or antigen-binding fragment thereof comprises: a heavy chain variable region (VH) that comprises SEQ ID NO: 7, and a light chain variable region (VL) that comprises SEQ ID NO: 8.
The method of claim 24, wherein the anti-PD1 antibody comprises an antibody or an antigen binding fragment thereof which specifically binds human PD1, and comprises:

a heavy chain variable region that comprises: a HCDR1 of SEQ ID NO: 12, HCDR2 of SEQ ID NO: 13, and HCDR3 of SEQ ID NO: 14; and a light chain variable region that comprises LCDR1 of SEQ ID NO: 15, LCDR2 of SEQ ID NO: 16, and LCDR3 of SEQ ID NO: 17.
The method of claim 27, wherein the anti-PD1 antibody or antigen binding fragment thereof which specifically binds human PD1 and comprises a heavy chain variable region (VH) comprising an amino acid sequence of SEQ ID NO: 18 and a light chain variable region (VL) comprising an amino acid sequence of SEQ ID NO: 19.
The method of claim 24 further comprising the administration of chemotherapy.
The method of claim 29, wherein the chemotherapy is cyclophosphamide, doxorubicin, vincristine, and prednisone.