WO2021102372A1 - Monoclonal antibodies that target human ox40 - Google Patents

Abstract

The present disclosure provides isolated monoclonal antibodies or antigen-binding portions thereof that specifically bind to OX40 preferably human OX40 with high affinity, and can enhance tumor-targeting immune response by activating tumor-specific effector and memory T-cells. The disclosure also provides antibodies that are chimeric, humanized, bispecific, derivatized, single chain antibodies or portions of fusion proteins. Nucleic acid molecules encoding the antibodies of the disclosed invention and hybridoma are also provided. Pharmaceutical compositions comprising the antibodies of the disclosed invention are also provided. This disclosure also provides methods for regulating humoral and cellular immune responses, as well as methods for treating cancer using an anti-OX40 agonist antibody of the disclosed invention.

Description

MONOCLONAL ANTIBODIES THAT TARGET HUMAN 0X40

CROSS REFERENCE TO RELATED APPLICATION

[1] This application claims priority to U.S. Provisional Application No. 62/938,293, filed November 20, 2019, the disclosure of which is incorporate by reference herein in its entirety.

INCORPORATION OF SEQUENCE LISTING

[2] This application includes a Sequence Listing which is being submitted in ASCII format via EFS-Web, named "AVI104PCT_ST25.txt,” which is 17 KB in size and created on November 20, 2020. The contents of the Sequence Listing are incorporated herein by reference in their entirety.

BACKGROUND

[3] 0X40, also known as CD134, TNFRSF4 or ACT-35, is a member of the tumor necrosis factor receptor superfamily. 0X40 is primarily found on activated CD4+ and CD8+ T cells, regulatory T (Treg) cells effector T cells and natural killer (NK) cells (Croft et ah, 2009). The binding partner for 0X40 (CD134, TNFESF4), e.g., OX40L, CD252 or TNFSF4 is predominantly present on APC (antigen presenting cells) and the 0X40 signaling can provide costimulatory signals to CD4 and CD8 T cells, leading to enhanced cell activation, proliferation, effector function and apoptosis inhibition of T cells. 0X40 signaling also enhances memory T cell development and function.

[4] 0X40 is a type I transmembrane glycoprotein. The extracellular segment of 0X40 consists of three cysteine-rich domains and one C-terminal incomplete CRD (Deanne M et al. 2006). 0X40 is a secondary co-stimulatory molecule. Unlike CD28, 0X40 is not expressed on the surfaces of resting T-cells but is highly expressed 24-72 hours after T-cell activation. The ligand OX40L ( CD252 or TNFSF4) of 0X40 is a type II transmembrane glycoprotein and is expressed on activated antigen presenting cells APC such as Macrophages, dendritic cells, B cells, etc. (Godfrey, W R et al., 1994). The OX40/OX40L signaling plays a very important role in the activation, proliferation and apoptosis inhibition of T cells. OX40/OX40L binding also regulates cytokine production from T cells, antigen-presenting cells, NK cells, and NKT cells, and modulates cytokine receptor signaling. In line with these important modulatory functions, OX40/OX40L signaling has been found to play a central role in the development of multiple inflammatory and autoimmune diseases, making them promising candidates for intervention in the clinic. Conversely, stimulating 0X40 has shown it to be a candidate for therapeutic immunization strategies for cancer and infectious disease. Several anti-OX40 monoclonal antibodies are currently tested in early phase cancer clinical trials. Studies show that activated 0X40 antibodies can effectively promote the proliferation and activation of T cells and produce better anti-tumor effects (Brendan D. Curti et al. (2013) Cancer Res 73: 7189-7198). These preclinical evidences support their clinical development.

[5] Combination therapies for chemotherapeutic agents are increasing common for oncology indications. Often, such combination treatments are based upon pre-clinical data that demonstrate synergistic efficacy relative to either agent alone. As a result, most combination therapies are based upon concurrent, or close to concurrent, administration of one or more agents. For example, the combination therapy of monoclonal antibodies (mAbs), 0X40 with PD-1 and/or CTLA-4 with the regulation of different non-redundant Tcell signaling pathways, has been used in the clinical studies for treating advanced or recurrent solid tumors: non-small cell lung cancer, squamous cell carcinoma of the head and neck, renal cell carcinoma, melanoma, bladder, soft tissue sarcoma, triple-negative breast cancer, and colorectal carcinoma displaying micro satellite instability. In addition, Immuno-therapy study of medication anti-OX40 by Itself or in combination with two monoclonal antibodies, ipilimumab (YERVOY®; anti-CTLA-4) and/or Nivolumab (anti-PD-1), is currently in clinical investigation for patients with solid cancers that are advanced or have spread (Sponsored by Bristol-Myers Squibb). In addition, the combinational therapy of 0X40 and atezolizumab (anti-PD-Ll) is in Phase lb trial to evaluate anti-tumor activity and evidence of prolonged stable diseases (Aaron R. et al., 2016).

[6] The current clinical approved immunotherapies targeting immune checkpoints, such as PD-1 and CTLA-4 have shown promising clinical results. However, the response rate of patients to these approved agents is still not satisfactory. As a result, there is a need in the art to identify a highly efficient anti-OX40 antibody to be used alone or as combinational therapeutic agents with other drugs treatment regimens for any given combination.

SUMMARY OF THE INVENTION [7] The present disclosure provides isolated monoclonal antibodies, or antigen-binding portions thereof, that specifically bind to human 0X40 (hOX40) and activates 0X40 signaling thereby contributing to T cell-mediated immunity.

[8] According to an aspect, the invention provides an isolated monoclonal antibody, or antigen binding portion thereof comprising: (a) a heavy chain variable region CDR1 comprising SEQ ID NO:3; (b) a heavy chain variable region CDR2 comprising SEQ ID NO:4; (c) a heavy chain variable region CDR3 comprising SEQ ID NO:5; (d) a light chain variable region CDR1 comprising SEQ ID NO:6; (e) a light chain variable region CDR2 comprising Leu-Ala-Ser (SEQ ID NO:7) and (f) a light chain variable region CDR3 comprising SEQ ID NO:8; wherein said antibody or portion specifically binds to human 0X40 and activates 0X40 signaling thereby contributing to T cell-mediated immunity.

[9] According to another aspect, the invention provides an isolated monoclonal antibody, or antigen binding portion thereof comprising: (a) a heavy chain variable region CDR1 comprising SEQ ID NO: 19; (b) a heavy chain variable region CDR2 comprising SEQ ID NO: 20; (c) a heavy chain variable region CDR3 comprising SEQ ID NO:21; (d) a light chain variable region CDR1 comprising SEQ ID NO:22; (e) a light chain variable region CDR2 comprising Tyr-Thr-Ser (SEQ ID NO:23) and (f) a light chain variable region CDR3 comprising SEQ ID NO:24; wherein said antibody or portion specifically binds to human 0X40 and activates 0X40 signaling thereby contributing to T cell-mediated immunity.

[10] According to yet another aspect, the invention provides an isolated monoclonal antibody, or antigen binding portion thereof comprising: (a) a heavy chain variable region CDR1 comprising SEQ ID NO:35; (b) a heavy chain variable region CDR2 comprising SEQ ID NO:36; (c) a heavy chain variable region CDR3 comprising SEQ ID NO:37; (d) a light chain variable region CDR1 comprising SEQ ID NO:38; (e) a light chain variable region CDR2 comprising Leu-Ala-Ser (SEQ ID NO:39) and (f) a light chain variable region CDR3 comprising SEQ ID NO:40; wherein said antibody or portion specifically binds to human 0X40 and activates 0X40 signaling thereby contributing to T cell-mediated immunity.

[11] In some embodiments, the monoclonal antibody, or said antigen-binding portion thereof stimulates an anti-tumor immune response. In some embodiments, the monoclonal antibody can be a chimeric antibody or a humanized antibody. In some embodiments, the anti-OX40 antibodies activate 0X40 signaling. [12] According to another aspect, the invention pertains to an isolated anti-OX40 monoclonal antibody, or antigen-binding portion thereof, comprising: (a) a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 3, 4 and 5; and (b) a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 2, 6, 7 and 8.

[13] According to another aspect, the invention pertains to an isolated anti-OX40 monoclonal antibody, or antigen-binding portion thereof, comprising: (a) a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 17, 19, 20 and 21; and (b) a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 18, 22, 23 and 24.

[14] According to another aspect, the invention pertains to an isolated anti-OX40 monoclonal antibody, or antigen-binding portion thereof, comprising: (a) a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 33, 35, 36 and 37; and (b) a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 34, 38, 39 and 40.

[15] In a preferred embodiment, an isolated monoclonal antibody or an antigen-binding portion thereof that specifically binds to human 0X40, wherein said antibody comprises: a heavy chain variable domain selected from SEQ ID NO: 1, 17 or 33 and a light chain variable domain selected from SEQ ID NO: 2, 18 or 34. In some embodiments, the monoclonal antibody, or an antigen-binding portion thereof stimulates an anti-tumor immune response.

[16] According to yet another aspect, the antibodies of the invention can be, for example, full-length antibodies, for example of an IgGl, IgG2, IgG3, or IgG4 isotype. Alternatively, the disclosed antibodies can be antibody fragments, such as Fab, Fab' and F(ab')2 fragments, diabody, triabody, tetrabody, single-chain variable region fragment (scFv), disulfide- stabilized variable region fragment (dsFv), and half antibodies.

[17] The antibodies of the disclosed invention can be further engineered into formats suitable for human therapeutics by modifications that minimize immunogenicity. Suitable antibodies include, but are not limited to chimeric antibodies and humanized antibodies. The affinity, stability and specificity of the disclosed antibodies can also be further optimized by techniques known to one of skill in the art such as light-chain shuffling. Other formats can involve oligomerization (multivalent), drug conjugation, bispecific antibody and fusion of the disclosed antibodies with other functional proteins. The drug conjugation can be an immunoconjugate comprising a CpG oligodeoxynucleotide.

[18] In yet another aspect, the invention provides a bispecific antibody comprising an antibody or portion binding to PD-1 or CTLA-4 , or an antibody or portion binding to hOX40, or an antibody or portion binding to other immune checkpoint targets, cancer-related targets, and immune-related disease targets. In another aspect, a bispecific antibody comprising an antibody or portion binding to 0X40. In another aspect, a multivalent anti- 0X40 antibody comprising three or more hPD-1 or hCTLA-4 binding portions or other immune checkpoint targets, cancer-related targets, and immune-related disease targets.

[19] In yet another aspect, a pharmaceutical composition comprising an isolated monoclonal antibody, or antigen-binding portion thereof and a pharmaceutically acceptable carrier are also provided.

[20] In yet another aspect, the invention provides method of enhancing an immune response using the anti-hOX40 antibodies of the disclosed invention. For example, in one embodiment, the disclosed invention provides a method for treating a subject in need thereof, wherein said response is indicated by activating tumor- specific effector and memory T-cells and enhancing tumor-targeting immune response, comprising the step of administering to the subject an effective amount of the antibody or antigen-binding portion of the disclosed invention.

[21] In yet another aspect, the invention provides a method for treating cancer in a human comprising the step of administering to the human the antibody or antigen-binding portion of the disclosed invention in an amount effective to treat said cancer and infectious diseases.

[22] In yet another aspect, the invention pertains to a monoclonal antibody or an antigen binding portion thereof that specifically binds to human 0X40, wherein said antibody comprises: a heavy chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NOs: 9, 11, 12 and 13; and a light chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NOs: 10, 14,

15 and 16. In yet another aspect, the invention also provides nucleic acid molecules encoding the heavy and/or light chain, or antigen-binding portions thereof, of an anti-OX40 antibody. [23] In yet another aspect, the invention relates to a monoclonal antibody or an antigen binding portion thereof that specifically binds to human 0X40, wherein said antibody comprises: a heavy chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NOs: 25, 27, 28 and 29; and a light chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NOs: 26, 30, 31 and 32.

[24] In yet another aspect, the invention relates to a monoclonal antibody or an antigen binding portion thereof that specifically binds to human 0X40, wherein said antibody comprises: a heavy chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NOs: 41, 43, 44 and 45; and a light chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NOs: 42, 46, 47 and 48.

[25] Other features and advantages of the instant disclosure will be apparent from the following detailed description and examples, which should not be construed as limiting. The contents of all references, GenBank entries, patents and published patent applications cited throughout this application are expressly incorporated herein by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

[26] Figure 1 shows results of binding assay for certain anti-human 0X40 monoclonal antibodies of the present invention.

[27] Figure 2 shows results of an in vitro agonistic reporter assay for certain anti-human 0X40 monoclonal antibodies of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

[28] The following embodiments and aspects thereof are described and illustrated in conjunction with systems, compositions and methods which are meant to be exemplary and illustrative, not limiting in scope.

[29] The present disclosure relates to an isolated monoclonal antibody that results in the activation of the 0X40 signaling and contribute towards the T-cell mediated immunity. In certain embodiments, the antibodies of the disclosed invention are derived from identified heavy (SEQ ID NO: 1) and light chain (SEQ ID NO: 2) germline sequences and/or comprise identified structural features such as CDR regions comprising identified amino acid sequences. This disclosure provides isolated antibodies, methods of making such antibodies and antigen-binding portions thereof of the disclosed invention. This disclosure also relates to methods of using the antibodies, such as using the agonistic 0X40 antibodies of the disclosed invention to enhance the tumor targeting immune responses, alone or in combination with other immuno stimulatory antibodies. The current invented antibody also relates to the modified formats by oligomerization, drug conjugation, bi-specific antibodies and the fusion with other functional proteins suitable for human therapeutics that minimize immunogenicity and maximize affinity, stability and specificity. Accordingly, also provided are methods of using the agonistic 0X4 antibodies of the disclosed invention for example, including but not limited to, treating cancer in a human.

[30] The term "epitope" as used herein can include any protein determinant capable of specific binding to an immunoglobulin or T-cell receptor. Epitopic determinants usually consist of chemically active surface groupings of molecules such as amino acids or sugar side chains and usually have specific three-dimensional structural characteristics, as well as specific charge characteristics.

[31] The term "immune response" as used herein can refer to the action of or activation of, for example, lymphocytes, antigen presenting cells, phagocytic cells, granulocytes, and soluble macromolecules produced by the above cells or the liver (including antibodies, cytokines, and complement) that results in selective damage to, destruction of, blocking of, or elimination from an organism of invading pathogens, cells or tissues infected with pathogens, interaction within molecules, cancerous cells, or, in cases of autoimmunity or pathological inflammation, normal organismal cells or tissues. The immune response, as used herein, refers to the activation of T-lymphocytes via agonistic interaction with 0X40 for enhancing the T-cell mediated immune response against the cancer and other infectious diseases.

[32] An "antigen-specific T cell response" as used herein can refer to responses by a T cell that result from stimulation of the T cell with the antigen for which the T cell is specific. Non-limiting examples of responses by a T cell upon antigen- specific stimulation include, but are not limited to, proliferation and cytokine production (e.g., IL-2 production). [33] The term "antibody" as used herein can include whole antibodies, F(ab')2 fragment, diabody, triabody, tetrabody, bispecific antibody, monomeric antibodies and any antigen binding fragment (i.e., "antigen-binding portion") or single-chain variable region fragment (scFv), or disulfide- stabilized variable region fragment (dsFv) thereof. Whole antibodies are glycoproteins comprising at least two heavy (H) chains and two light (L) chains inter connected by disulfide bonds. Each heavy chain is comprised of a heavy chain variable region (abbreviated herein as VH) and a heavy chain constant region. The heavy chain constant region is comprised of three domains, CHI, CH2 and CH3. Each light chain is comprised of a light chain variable region (abbreviated herein as VL) and a light chain constant region (CL). The light chain constant region is comprised of one domain, CL. The VH and VL regions can be further subdivided into regions of hypervariability, termed complementarity determining regions (CDR), interspersed with regions that are more conserved, termed framework regions (FR). Each VH and VL is composed of three CDRs and four FRs, arranged from amino-terminus to carboxy-terminus in the following order: FR1, CDR1, FR2, CDR2, FR3, CDR3, FR4. The variable regions of the heavy and light chains contain a binding domain that interacts with an antigen. The constant regions of the antibodies can mediate the binding of the immunoglobulin to host tissues or factors, including various cells of the immune system (e.g., effector cells) and the first component (Clq) of the classical complement system.

[34] The term "antigen-binding portion" of an antibody (or simply "antibody portion"), as used herein, can refer to one or more fragments of an antibody that retain the ability to specifically bind to an antigen (e.g., a 0X40 protein). It has been shown that the antigen binding function of an antibody can be performed by fragments of a full-length antibody. Examples of binding fragments encompassed within the term "antigen binding portion" of an antibody include (i) a Fab fragment, a monovalent fragment consisting of the VL, VH, CL and CHI domains; (ii) a F(ab')2 fragment, a bivalent fragment comprising two Fab fragments linked by a disulfide bridge at the hinge region; (iii) a Fab' fragment, which is essentially a Fab with part of the hinge region(see, FUNDAMENTAL IMMUNOLOGY (Paul ed., 3.sup.rd ed. 1993); (iv) a Fd fragment consisting of the VH and CHI domains; (v) a Fv fragment consisting of the VL and VH domains of a single arm of an antibody, (vi) a dAb fragment (Ward et ah, (1989) Nature 341 :544-546), which consists of a VH domain; (vii) an isolated complementarity determining region (CDR); and (viii) a nanobody, a heavy chain variable region containing a single variable domain and two constant domains. Furthermore, although the two domains of the Fv fragment, VL and VH are encoded by separate genes, they can be joined, using recombinant methods, by a synthetic linker that enables them to be made as a single protein chain in which the VL and VH regions pair to form monovalent molecules (known as single chain Fv (scFv); see e.g., Bird et al. (1988) Science 242:423-426; and Huston et al. (1988) Proc. Natl. Acad. Sci. USA 85:5879-5883). Such single chain antibodies are also intended to be encompassed within the term "antigen -binding portion" of an antibody. These antibody fragments are obtained using conventional techniques known to those of skill in the art, and the fragments are screened for utility in the same manner as intact antibodies.

[35] An "isolated antibody", as used herein, can refer to an antibody that is substantially free of other antibodies having different antigenic specificities (e.g., an isolated antibody that specifically binds a 0X40 protein can be substantially free of antibodies that specifically bind antigens other than 0X40 proteins). An isolated antibody that specifically binds a human 0X40 protein can, however, have cross-reactivity to other antigens, such as 0X40 proteins from other species. Moreover, an isolated antibody can be substantially free of other cellular material and/or chemicals.

[36] Anti-OX40 agonistic antibody-producing cells, e.g., hybridomas, can be selected, cloned and further screened for desirable characteristics, including robust growth, high antibody production and desirable antibody characteristics, as further discussed below. In a preferred embodiment, the anti-OX40 antibodies were created by electro fusion of human 0X40- immunized mouse spleenocytes (Balb/c strain) with SP2/0-Agl4 cells (ATCC). Splenocytes were collected from balb/c mice hyperimmunized with purchased recombinant human OX-40 protein. Cell fusion was performed with the standard protocol from BTX. Fused cells were seeded into 96- well plates and beads- screening was conducted to identify antigen-bound magnetic beads that contain antibodies which interact with human 0X40 protein. Positive wells were further expanded and follow a limited dilution to isolate monoclonal hybridomas. Purified antibodies were used to test their ability to trigger 0X40 signaling by a reporter cell system (Promega). The terms "monoclonal antibody" or "monoclonal antibody composition" as used herein can refer to a preparation of antibody molecules of single molecular composition. A monoclonal antibody composition displays a single binding specificity and affinity for a particular epitope. The monoclonal antibodies herein are developed in the forms of humanized biologies, bispecific antibodies and antibody-fusion proteins.

[37] The term "recombinant human antibody", as used herein, can refer to all human antibodies that are prepared, expressed, created or isolated by recombinant means, such as (a) antibodies isolated from an animal (e.g., a mouse) that is transgenic or transchromosomal for human immunoglobulin genes or a hybridoma prepared therefrom (described below), (b) antibodies isolated from a host cell transformed to express the human antibody, e.g., from a transfectoma, (c) antibodies isolated from a recombinant, combinatorial human antibody library, and (d) antibodies prepared, expressed, created or isolated by any other means that involve splicing of human immunoglobulin gene sequences to other DNA sequences. Such recombinant human antibodies have variable regions in which the framework and CDR regions are derived from human germline immunoglobulin sequences. In certain embodiments, however, such recombinant human antibodies can be subjected to in vitro mutagenesis (or, when an animal transgenic for human Ig sequences is used, in vivo somatic mutagenesis) and thus the amino acid sequences of the VH and VL regions of the recombinant antibodies are sequences that, while derived from and related to human germline VH and VL sequences, may not naturally exist within the human antibody germline repertoire in vivo.

[38] The term "isotype" can refer to the antibody class (e.g., IgM or IgGl) that is encoded by the heavy chain constant region genes.

[39] The phrases "an antibody recognizing an antigen" and "an antibody specific for an antigen" are used interchangeably herein with the term "an antibody which binds specifically to an antigen."

[40] A "humanized antibody" has a sequence that differs from the sequence of an antibody derived from a non-human species by one or more amino acid substitutions, deletions, and/or additions, such that the humanized antibody is less likely to induce an immune response, and/or induces a less severe immune response, as compared to the non-human species antibody, when it is administered to a human subject. In one embodiment, certain amino acids in the framework and constant domains of the heavy and/or light chains of the non human species antibody are mutated to produce the humanized antibody. Additional framework region modifications can be made within the human framework sequences. In another embodiment, the term "humanized antibody" can refer to antibodies in which CDR sequences derived from the germline of another mammalian species, such as a mouse, have been grafted onto human framework sequences. In another embodiment, the constant domain(s) from a human antibody are fused to the variable domain(s) of a non-human species. In another embodiment, one or more amino acid residues in one or more CDR sequences of a non-human antibody are changed to reduce the likely immunogenicity of the non-human antibody when it is administered to a human subject, wherein the changed amino acid residues either are not critical for immuno specific binding of the antibody to its antigen, or the changes to the amino acid sequence that are made are conservative changes, such that the binding of the humanized antibody to the antigen is not significantly worse than the binding of the non-human antibody to the antigen. Examples of how to make humanized antibodies may be found in U.S. Pat. Nos. 6,054,297, 5,886, 152 and 5,877,293.

[41] The term "chimeric antibody" can refer to antibodies in which the variable region sequences can be derived from one species and the constant region sequences can be derived from another species, such as an antibody in which the variable region sequences can be derived from a mouse antibody and the constant region sequences can be derived from a human antibody.

[42] As used herein, an antibody that "specifically binds human 0X40" can refer to an antibody that binds to a human 0X40 protein (and possibly an 0X40 protein from one or more non-human species) and can enhance tumor-targeting immune response by activating tumor- specific effector and memory T-cells. Agonistic 0X40 antibody can potentially serve as single therapy or in combination with other immune checkpoint therapies. Preferably, the antibody binds to a human 0X40 protein with "high affinity," namely with a Kd of 1x10 M or less, more preferably 5x10 -8 M or less, more preferably 3x10 -8 M or less, more preferably lxlO ⁸ M or less, more preferably 5xl0⁹ M or less or even more preferably lxlO ⁹ M or less.

[43] The term "high affinity" for an IgG antibody can refer to an antibody having an EC50 of

1x10 -6 M or less, more preferably 1x10 -7 M or less, even more preferably 1x10 -8 M or less, even more preferably lxlO ⁹ M or less, even more preferably lxlO ¹⁰ M or less for a target antigen. However, "high affinity" binding can vary for other antibody isotypes. [44] As used herein, the term "inhibit" refers to any decrease in, for example a particular action, function, or interaction. For example, a biological function, such as the function of a protein and/or binding of one protein to another, is inhibited if it is decreased as compared to a reference state, such as a control like a wild-type state or a state in the absence of an applied agent. For example, the binding of a 0X40 protein to one or more of its ligands, such as, and/or resulting 0X40 signaling and immune effects is increased, if the binding, signaling, and other immune effects are increased due to contact with an agent, such as an anti-OX40 antibody, in comparison to when the 0X40 protein is not contacted with the agent. Such inhibition or deficiency can be induced, such as by application of agent at a particular time and/or place, or can be constitutive, such as by continual administration. Such inhibition or deficiency can also be partial or complete (e.g., essentially no measurable activity in comparison to a reference state, such as a control like a wild-type state). Essentially complete inhibition or deficiency is referred to as blocked.

[45] The term "subject" can refer to any human or non-human animal. The term "non-human animal" includes all vertebrates, e.g., mammals and non-mammals, such as non-human primates, sheep, dogs, cats, cows, horses, chickens, rabbits, mice, rats, amphibians, and reptiles, although mammals are preferred, such as non-human primates, sheep, dogs, cats, cows and horses.

[46] The binding of an antibody of the disclosed invention to 0X40 can be assessed using one or more techniques well established in the art. For example, in a preferred embodiment, the purified anti-OX40 antibody can be tested by various biochemical assays such as ELISA assays, for example by assessment of the binding with recombinant 0X40 protein. Still other suitable binding assays include but are not limited to a flow cytometry assay in which the antibody is reacted with a cell line that expresses human 0X40, such as SP2/0-Agl4 cells that have been transfected to express 0X40 protein (e.g., human 0X40) on their cell surface. Additionally, the binding of the antibody, including the binding kinetics (e.g., K_D value) can be tested in Biacore binding assays and the like.

[47] B cells or hybridoma expressing the antibodies against the antigen can be isolated and the nucleic acid sequences encoding the heavy chain variable domain (VH) and light chain variable domain (VL) can be obtained by next generation sequencing. The encoded amino acid sequences of VH and VL can be obtained from the nucleic acid sequences. These techniques are well known by the person of ordinary skill in the art. The VH amino acid sequence of Clone# 1C9-1C9 is shown in SEQ ID NO:l. The VL amino acid sequence of Clone# 1C9-1C9 is shown in SEQ ID NO:2. The VH amino acid sequence of Clone# 3F4- 1C2 is shown in SEQ ID NO: 17. The VL amino acid sequence of Clone# 3F4-1C2 is shown in SEQ ID NO: 18. The VH amino acid sequence of Clone# 2D12-5F11 is shown in SEQ ID NO:33. The VL amino acid sequence of Clone# 2D12-5F11 is shown in SEQ ID NO:34.

[48] Accordingly, in one aspect, this disclosure provides an isolated monoclonal antibody, or antigen-binding portion thereof comprising: (a) a heavy chain variable region comprising an amino acid sequence comprising SEQ ID NO:l; and (b) a light chain variable region comprising an amino acid sequence comprising SEQ ID NO:2; wherein the antibody specifically binds to human 0X40.

[49] In another aspect, this disclosure provides an isolated monoclonal antibody, or antigen binding portion thereof comprising: (a) a heavy chain variable region comprising an amino acid sequence comprising SEQ ID NO: 17; and (b) a light chain variable region comprising an amino acid sequence comprising SEQ ID NO: 18 ; wherein the antibody specifically binds to human 0X40.

[50] In another aspect, this disclosure provides an isolated monoclonal antibody, or antigen binding portion thereof comprising: (a) a heavy chain variable region comprising an amino acid sequence comprising SEQ ID NO:33; and (b) a light chain variable region comprising an amino acid sequence comprising SEQ ID NO:34 ; wherein the antibody specifically binds to human 0X40.

[51] In some embodiments, the anti-OX40 monoclonal antibody, or an antigen-binding portion thereof stimulates an anti-tumor immune response. In some embodiments, the anti- 0X40 monoclonal antibody can be a bispecific, antibody-fusion protein, immunoconjugate, immunotoxins and/or chimeric antibody.

[52] In another aspect, this disclosure provides antibodies that comprise the heavy chain and light chain CDR1, CDR2 and CDR3 of Clone# 1C9-1C9. The amino acid sequence of the VH CDR1 of Clone# 1C9-1C9 is shown in SEQ ID NO:3. The amino acid sequence of the VH CDR2 of Clone# 1C9-1C9 is shown in SEQ ID NO:4. The amino acid sequence of the VH CDR3 of Clone# 1C9-1C9 is shown in SEQ ID NO:5. The amino acid sequences of the VL CDR1 of Clone# 1C9-1C9 is shown in SEQ ID NO:6. The amino acid sequences of the VL CDR2 of Clone# 1C9-1C9 is Leu-Ala-Ser, shown in SEQ ID NO:7. The amino acid sequences of the VL CDR3 of Clone# 1C9-1C9 is shown in SEQ ID NO:8.

[53] In another aspect, this disclosure provides antibodies that comprise the heavy chain and light chain CDR1, CDR2 and CDR3 of Clone# 3F4-1C2. The amino acid sequence of the VH CDR1 of Clone# 3F4-1C2 is shown in SEQ ID NO: 19. The amino acid sequence of the VH

CDR2 of Clone# 3F4-1C2 is shown in SEQ ID NO:20. The amino acid sequence of the VH

CDR3 of Clone# 3F4-1C2 is shown in SEQ ID NO:21. The amino acid sequences of the VL

CDR1 of Clone# 3F4-1C2 is shown in SEQ ID NO:22. The amino acid sequences of the VL

CDR2 of Clone# 3F4-1C2 is Tyr-Thr-Ser, shown in SEQ ID NO:23. The amino acid sequences of the VL CDR3 of Clone# 3F4-1C2 is shown in SEQ ID NO:24.

[54] In another aspect, this disclosure provides antibodies that comprise the heavy chain and light chain CDR1, CDR2 and CDR3 of Clone# 2D12-5F11. The amino acid sequence of the VH CDR1 of Clone# 2D12-5F11 is shown in SEQ ID NO:35. The amino acid sequence of the VH CDR2 of Clone# 2D12-5F11 is shown in SEQ ID NO:36. The amino acid sequence of the VH CDR3 of Clone# 2D12-5F11 is shown in SEQ ID NO:37. The amino acid sequences of the VL CDR1 of Clone# 2D12-5F11 is shown in SEQ ID NO:38. The amino acid sequences of the VL CDR2 of Clone# 2D12-5F11 is Leu-Ala-Ser, shown in SEQ ID NO:39. The amino acid sequences of the VL CDR3 of Clone# 2D12-5F11 is shown in SEQ ID NO:40.

[55] The CDR regions can be delineated using IMGT reference directory (Lefranc, M.-P. and Lefranc, G. The Immunoglobulin FactsBook Academic Press, London, UK (2001))

[56] In another aspect, this disclosure provides amino acid sequences encoding the heavy chain and light chain variable domains of the monoclonal antibody Clone# 1C9-1C9 (Table 1).

[57] In another aspect, this disclosure provides amino acid sequences encoding the heavy chain and light chain variable domains of the monoclonal antibody Clone# 3F4-1C2 (Table 1).

[58] In another aspect, this disclosure provides amino acid sequences encoding the heavy chain and light chain variable domains of the monoclonal antibody Clone# 2D12-5F11 (Table 1). [59] In another aspect, this disclosure provides polynucleotide sequences encoding the heavy chain and light chain variable domains of the monoclonal antibody Clone# 1C9-1C9 (Table 2).

[60] In another aspect, this disclosure provides polynucleotide sequences encoding the heavy chain and light chain variable domains of the monoclonal antibody Clone# 3F4-1C2 (Table 2).

[61] In another aspect, this disclosure provides polynucleotide sequences encoding the heavy chain and light chain variable domains of the monoclonal antibody Clone# 2D12-5F11 (Table 2).

[62] Antibodies can be affinity maturated by light-chain shuffling combined with or without random mutagenesis of its heavy chain variable domain and panning against 0X40. The VL CDR1, CDR2 and CDR3 of the antibodies mentioned in this disclosed invention can be optimized with light-chain shuffling to create other 0X40 binding molecules of the disclosed invention.

[63] An antibody of the disclosed invention further can be prepared using an antibody having one or more of the VH and/or VL sequences disclosed herein as starting material to engineer a modified antibody, which modified antibody can have altered properties from the starting antibody. An antibody can be engineered by modifying one or more residues within one or both variable regions (i.e., VH and/or VL), for example within one or more CDR regions and/or within one or more framework regions. Additionally, or alternatively, an antibody can be engineered by modifying residues within the constant region(s), for example to alter the effector function(s) of the antibody.

[64] In certain embodiments, CDR grafting can be used to engineer variable regions of antibodies. Antibodies interact with target antigens predominantly through amino acid residues that are located in the six heavy and light chain complementarity determining regions (CDRs). For this reason, the amino acid sequences within CDRs can be more diverse between individual antibodies than sequences outside of CDRs.

[65] Because CDR sequences can be responsible for most antibody- antigen interactions, it can be possible to express recombinant antibodies that mimic the properties of specific naturally occurring antibodies by constructing expression vectors that include CDR sequences from the specific naturally occurring antibody grafted onto framework sequences from a different antibody with different properties (see, e.g., Riechmann et al. (1998) Nature 332:323-327; Jones et al. (1986) Nature 321: 522-525; Queen et al. (1989) Proc. Natl. Acad.

[66] Accordingly, another embodiment of the disclosed invention pertains to an isolated monoclonal antibody, or antigen-binding portion thereof, comprising a heavy chain variable region comprising CDR1, CDR2, and CDR3 sequences comprising an amino acid sequence of SEQ ID NO:3, SEQ ID NO:4, and SEQ ID NO:5, respectively, and a light chain variable region a comprising CDR1, CDR2, and CDR3 sequences comprising an amino acid sequence of SEQ ID NO:6, Leu-Ala-Ser SEQ ID NO:7, and SEQ ID NO:8, respectively.

[67] Accordingly, another embodiment of the disclosed invention pertains to an isolated monoclonal antibody, or antigen-binding portion thereof, comprising a heavy chain variable region comprising CDR1, CDR2, and CDR3 sequences comprising an amino acid sequence of SEQ ID NO: 19, SEQ ID NO:20, and SEQ ID NO:21, respectively, and a light chain variable region a comprising CDR1, CDR2, and CDR3 sequences comprising an amino acid sequence of SEQ ID NO:22, Tyr-Thr-Ser SEQ ID NO:23, and SEQ ID NO:24, respectively.

[68] Accordingly, another embodiment of the disclosed invention pertains to an isolated monoclonal antibody, or antigen-binding portion thereof, comprising a heavy chain variable region comprising CDR1, CDR2, and CDR3 sequences comprising an amino acid sequence of SEQ ID NO:35, SEQ ID NO:36, and SEQ ID NO:37, respectively, and a light chain variable region a comprising CDR1, CDR2, and CDR3 sequences comprising an amino acid sequence of SEQ ID NO:38, Leu-Ala-Ser SEQ ID NO:39, and SEQ ID NO:40, respectively.

[69] Such framework sequences can be obtained from public DNA databases or published references that include germline antibody gene sequences. For example, germline DNA sequences for human heavy and light chain variable region genes can be found in the "VBase" human germline sequence database (available on the Internet at www.mrc- cpe.cam.ac.uk/vbase), as well as e.g., Sambrook et al. in Rabat et al. (1991), cited supra; Tomlinson et al. (1992) "The Repertoire of Human Germline YH Sequences Reveals about Fifty Groups of YH Segments with Different Hypervariable Loops" J. Mol. Biol. 227:776- 798; and Cox et al. (1994) "A Directory of Human Germ-line YH Segments Reveals a Strong Bias in their Usage" Eur. J. Immunol. 24:827 -836; the contents of each of which are expressly incorporated herein by reference. [70] Antibody protein sequences are compared against a compiled protein sequence database using one of the sequence similarity searching methods called the Gapped BLAST (Altschul et al. (1997), supra), which is well known to those skilled in the art. The compositions and methods of the presently disclosed invention are not limited to variants of the exemplary sequences disclosed herein but include those having at least 90%, at least 95% and at least 99% sequence identity to an exemplary sequence disclosed herein.

[71] Given that each of these antibodies Fab, can bind to human 0X40, the VH and VL sequences can be "mixed and matched" to create other anti-OX40 binding molecules of the invention. Preferably, when VH and VL chains are mixed and matched, a VH sequence from a particular VH/VL pairing is replaced with a structurally similar VH sequence. Likewise, preferably a VL sequence from a particular VH/VL pairing is replaced with a structurally similar VL sequence.

[72] Accordingly, in one aspect, this disclosure provides an isolated monoclonal antibody, or antigen-binding portion thereof comprising: (a) a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NO:l; and (b) a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NO:2; wherein the antibody specifically binds human 0X40 and activate the 0X40 signaling that contribute to T-cell immunity.

[73] Accordingly, in one aspect, this disclosure provides an isolated monoclonal antibody, or antigen-binding portion thereof comprising: (a) a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 17; and (b) a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 18; wherein the antibody specifically binds human 0X40 and activate the 0X40 signaling that contribute to T-cell immunity.

[74] Accordingly, in one aspect, this disclosure provides an isolated monoclonal antibody, or antigen-binding portion thereof comprising: (a) a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NO:33; and (b) a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NO: 34; wherein the antibody specifically binds human 0X40 and activate the 0X40 signaling that contribute to T-cell immunity. [75] A nucleic acid molecule encoding the heavy or entire light chain of an anti-OX40 antibody or portions thereof can be isolated from any source that produces such an antibody. In various embodiments, the nucleic acid molecules are isolated from a B cell isolated from an animal immunized with 0X40 or from an immortalized cell derived from such a B cell that expresses an anti-OX40 antibody. Methods of isolating mRNA encoding an antibody are well-known in the art. See, e.g., Sambrook et al. The mRNA may be used to produce cDNA for use in the polymerase chain reaction (PCR) or cDNA cloning of antibody genes. In a preferred embodiment, the nucleic acid molecule is isolated from a hybridoma that has as one of its fusion partners a human immunoglobulin producing cell from a non-human transgenic animal. In another embodiment, the nucleic acid can be isolated from a non-human, non- transgenic animal. The nucleic acid molecules isolated from a non-human, non-transgenic animal may be used, e.g., for humanized antibodies.

[76] In another aspect, the present disclosure provides a pharmaceutical composition comprising one or more antibodies of the present invention formulated together with a pharmaceutically acceptable carrier. The composition may optionally contain one or more additional pharmaceutically active ingredients, such as another antibody or a drug. The pharmaceutical compositions of the disclosed invention also can be administered in combination therapy with, for example, another immunostimulatory agent, an anti-cancer agent, an antiviral agent, or a vaccine, such that the anti-OX40 antibody enhances the immune response stimulated by the vaccine.

[77] The pharmaceutical composition can comprise any number of excipients. Excipients that can be used include carriers, surface active agents, thickening or emulsifying agents, solid binders, dispersion or suspension aids, solubilizers, colorants, flavoring agents, coatings, disintegrating agents, lubricants, sweeteners, preservatives, isotonic agents, and combinations thereof. The selection and use of suitable excipients are taught in Gennaro, ed., Remington: The Science and Practice of Pharmacy, 20th Ed. (Lippincott Williams & Wilkins 2003), the disclosure of which is incorporated herein by reference.

[78] Therapeutic compositions typically must be sterile and stable under the conditions of manufacture and storage. The composition can be formulated as a solution, microemulsion, dispersion, liposome, or other ordered structure suitable to high drug concentration. Sterile injectable solutions can be prepared by incorporating the anti-OX40 antibody in the required amount in an appropriate solvent with one or a combination of ingredients enumerated above, as required, followed by filtered sterilization. Generally, dispersions are prepared by incorporating the active compound into a sterile vehicle that contains a basic dispersion medium and the required other ingredients from those enumerated above. In the case of sterile powders for the preparation of sterile injectable solutions, the preferred methods of preparation are vacuum drying and freeze-drying that yields a powder of the active ingredient plus any additional desired ingredient from a previously sterile-filtered solution thereof. The proper fluidity of a solution can be maintained, for example, by the use of a coating such as lecithin, by the maintenance of the required particle size in the case of dispersion and by the use of surfactants. Prolonged absorption of injectable compositions can be brought about by including in the composition an agent that delays absorption, for example, monostearate salts and gelatin.

[79] The antibodies of the present invention can be administered by a variety of methods known in the art, although for many therapeutic applications, the preferred route/mode of administration is subcutaneous, intramuscular, or intravenous infusion. As will be appreciated by the skilled artisan, the route and/or mode of administration will vary depending upon the desired results.

[80] In certain embodiments, the antibody compositions active compound may be prepared with a carrier that will protect the antibody against rapid release, such as a controlled release formulation, including implants, transdermal patches, and microencapsulated delivery systems. Biodegradable, biocompatible polymers can be used, such as ethylene vinyl acetate, polyanhydrides, polyglycolic acid, collagen, polyorthoesters, and polylactic acid. Many methods for the preparation of such formulations are patented or generally known to those skilled in the art. See, e.g., Sustained and Controlled Release Drug Delivery Systems (J. R. Robinson, ed., Marcel Dekker, Inc., New York, 1978).

[81] In certain embodiments, an anti-OX40 antibody of the disclosed invention can be orally administered, for example, with an inert diluent or an assimilable edible carrier. The compound (and other ingredients, if desired) can also be enclosed in a hard or soft-shell gelatin capsule, compressed into tablets, or incorporated directly into the subject's diet. For oral therapeutic administration, the anti-OX40 antibodies can be incorporated with excipients and used in the form of ingestible tablets, buccal tablets, troches, lozenge, capsules, elixirs, suspensions, syrups, wafers, and the like. To administer a compound of the disclosed invention by other than parenteral administration, it may be necessary to coat the compound with, or co-administer the compound with, a material to prevent its inactivation.

[82] Additional active compounds also can be incorporated into the disclosed compositions. In certain embodiments, an anti-OX40 antibody of the disclosed invention is co-formulated with and/or co-administered with one or more additional therapeutic agents. These agents include, without limitation, antibodies that bind other targets (e.g., antibodies that bind one or more growth factors or cytokines or their cell surface receptors, such as anti-PD-1 and anti- CTLA-4 antibody), antineoplastic agents, antitumor agents, chemotherapeutic agents, peptide analogues that activate CD40, soluble CD40L, one or more chemical agents that activates CD40, CpG oligodeoxynucleotides and/or other agents known in the art that can enhance an immune response against tumor cells, e.g., IFN-1, IL-2, IL-8, IL-12, IL-15, IL-18, IL-23, IFN-g, and GM-CSF. Such combination therapies may require lower dosages of the anti- 0X40 antagonist antibody as well as the co-administered agents, thus avoiding possible toxicities or complications associated with the various immunotherapies. The current clinical approved immunotherapies targeting immune checkpoints, such as PD-1 and CTLA-4 have shown promising clinical results. However, the response rate of patients to these approved agents is still not satisfactory. The new class of immune checkpoint targets on T-cell, including 0X40, can enhance tumor-targeting immune response by activating tumor- specific effector and memory T-cells. Agonistic 0X40 antibody can potentially serve as single therapy or in combination with other immune checkpoint therapies.

[83] Anti-OX40 antibodies of the disclosed invention and compositions comprising them also may be administered in combination with other therapeutic regimens, in particular in combination with radiation treatment.

[84] The pharmaceutical compositions of the disclosed invention can include pharmaceutically acceptable salts. A "pharmaceutically acceptable salt" can refer to a salt that retains the desired biological activity of the parent compound and does not impart any undesired toxicological effects. Examples of such salts include acid addition salts and base addition salts. Acid addition salts include those derived from nontoxic inorganic acids, such as hydrochloric, nitric, phosphoric, sulfuric, hydrobromic, hydroiodic, phosphorous and the like, as well as from nontoxic organic acids such as aliphatic mono- and dicarboxylic acids, phenyl-substituted alkanoic acids, hydroxy alkanoic acids, aromatic acids, aliphatic and aromatic sulfonic acids and the like. Base addition salts include those derived from alkaline earth metals, such as sodium, potassium, magnesium, calcium and the like, as well as from nontoxic organic amines, such as N,N'-dibenzylethylenediamine, N-methylglucamine, chloroprocaine, choline, diethanolamine, ethylenediamine, procaine and the like.

[85] Dosage regimens are adjusted to provide the optimum desired response (e.g., a therapeutic response). For example, a single dose can be administered, several divided doses can be administered over time or the dose can be proportionally reduced or increased as indicated by the exigencies of the therapeutic situation. It is especially advantageous to formulate parenteral compositions in dosage unit form for ease of administration and uniformity of dosage. Dosage unit form as used herein refers to physically discrete units suited as unitary dosages for the subjects to be treated; each unit contains a predetermined quantity of active compound calculated to produce the desired therapeutic effect in association with the required pharmaceutical carrier. Alternatively, the antibody can be administered as a sustained release formulation, in which case less frequent administration can be required.

[86] In certain embodiments, antibodies can be further developed into formats suitable for human therapeutics by modifications that minimize immunogenicity and maximize affinity, stability and specificity. Other formats which might involve oligomerization, drug conjugation and the fusion with other functional proteins.

[87] Bispecific antibodies or antigen-binding fragments can be produced by a variety of methods including fusion of hybridomas or linking of Fab' fragments. See, e.g., Songsivilai & Lachmarm, Clin. Exp. Immunol. 79: 315-321 (1990), Kostelny et ah, J. Immunol. 148:1547-1553 (1992). In addition, bispecific antibodies can be formed as "diabodies" or "Janusins." In some embodiments, the bispecific antibody binds to two different epitopes of 0X40. In some embodiments, the bispecific antibody has a first heavy chain and a first light chain from monoclonal antibody 1C9-1C9 (Table 1), and an additional antibody heavy chain and light chain. In some embodiments, the bispecific antibody has a first heavy chain and a first light chain from monoclonal antibody 3F4-1C2, and an additional antibody heavy chain and light chain. In some embodiments, the bispecific antibody has a first heavy chain and a first light chain from monoclonal antibody 2D12-5F11, and an additional antibody heavy chain and light chain.

Table 1. Anti-OX40 antibody amino acid sequences table.

Table 2. Nucleic acid sequences encoding anti-OX40 antibody variable domains.

[88] Example 1. Anti-OX40 antibody production.

[89] The antibodies were created by electro fusion of human OX40-immunized mouse spleenocytes (Balb/c strain) with SP2/0-Agl4 cells (ATCC). Splenocytes were collected from balb/c mice hyperimmunized with purchased recombinant human OX-40 protein. Cell fusion was performed with the standard protocol from BTX. Fused cells were seeded into 96- well plates and beads-screening was conducted to identify antigen-bound magnetic beads that contain antibodies which interact with human 0X40 protein. Positive wells were further expanded and follow a limited dilution to isolate monoclonal hybridomas. Purified antibodies were used to test their ability to trigger 0X40 signaling by a reporter cell system (Promega).

[90] Example 2. Anti- 0X40 antibody binding assay

[91] lxlO⁶ Jurkat-hOX40 overexpression cells were stained with 0.1, 0.3, 1 pg/ml AVI anti- hOX40 monoclonal antibody (clone 1C9-1C9, 2D12-5F11, or 3F4-1C2) for 30 minutes.

After washing, FITC-conjugated anti-mlgGl (Jackson immunoresearch) was used as secondary antibody to detect mouse anti-hOX40 antibody on the cell surface. Flow cytometry was performed using Cytek NF-3000 and data was analyzed with FlowJo. The results shown in Figure 1 demonstrate that these monoclonal antibodies bind human 0X40 on the cell surface.

[92] Example 3. Anti-OX40 antibody agonistic reporter assay

[93] The measurement of T cell activation was conducted by in vitro agonistic reporter assay. hFcgR2A and mFcgRl were transiently overexpressed on 293T cells. lxlO⁵ hFcgR2A and mFcgRl-overepxressed 293T cells and 3xl0⁵ Jurkat-OX-40-Fuc cells (Promega) were co cultured with various concentrations of anti-hOX40 antibodies (clone 1C9-1C9, 2D12-5F11, or 3F4-1C2) for 24 hours. After incubation, the cells were lysed with 60ul of IX passive lysis buffer (Promega). lOul of cell lyse was removed and mixed with 50ul of luciferase substrate. The luminescence was measured at by SpectraMax M5 Microplate Readers (Molecular Devices). The results shown in Figure 2 demonstrate that these monoclonal antibodies induced T-cell activation.

[94] Anti-OX40 antibody triggers the activation of 0X40 signaling that contribute to T cell- mediated immunity. Further the current invention can be used in treatment of cancers and infectious diseases.

[95] Although the above invention has been described in some detail by way of illustration and example for purposes of clarity of understanding, it is apparent to those skilled in the art that certain changes and modifications will be practiced. Therefore, the description and examples should not be construed as limiting the scope of the disclosed invention. [96] The disclosures of all publications, patents, patent applications and published patent applications referred to herein by an identifying citation are hereby incorporated herein by reference in their entirety. All publications herein are incorporated by reference to the same extent as if each individual publication or patent application was specifically and individually indicated to be incorporated by reference. The following description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[97] The sequence listing of the polynucleotide/peptide sequences described herein is included in the Appendix hereto, which is incorporated herein by reference in its entirety.

References

[98] Aaron R. Hansen et al., “Abstract CT097: A first-in-human phase I dose escalation study of the 0X40 agonist MOXR0916 in patients with refractory solid tumors”, 2016

[99] Bird, et al., “ Single-chain antigen-binding proteins”. Science. 1988 Oct, 242(4877):423-6.

[100] Brendan D. Curti et al., “0X40 Is a Potent Immune- Stimulating Target in Late-Stage Cancer Patients” (2013) Cancer Res 73: 7189-7198).

[101] Bristol-Myers Squibb sponsored “An Investigational Immuno-therapy Study of Experimental Medication BMS-986178 by Itself or in Combination With Nivolumab and/or Ipilimumab in Patients With Solid Cancers That Are Advanced or Have Spread” ClinicalTrials.gov Identifier: NCT02737475.

[102] Cox et al. (1994) "A Directory of Human Germ- line YH Segments Reveals a Strong Bias in their Usage" Eur. J. Immunol. 24:827 -836.

[103] Croft et al., “The Significance of 0X40 and OX40L to T cell Biology and Immune Disease”. Immunol Rev. 2009 May; 229(1): 173-191.

[104] Gennaro, ed., “Remington: The Science and Practice of Pharmacy”. 20th Edition. Lippincott Williams & Wilkins. 2003.

[105] Godfrey, W R et al., “Identification of a human OX-40 ligand, a costimulator of CD4+ T cells with homology to tumor necrosis factor.” (1994) J Exp Med 180: 757-762. [106] Huston, et al., Protein engineering of antibody binding sites: recovery of specific activity in an anti-digoxin single-chain Fv analogue produced in Escherichia coli”. Proc Natl Acad Sci U S A. 1988 Aug; 85(16): 5879-5883.

[107] J. R. Robinson ed., “Sustained and Controlled Release Drug Delivery Systems”. Marcel Dekker, Inc., New York, 1978.

[108] Jones et al., “Replacing the complementarity-determining regions in a human antibody with those from a mouse”. Nature. 1986; 4,321(6069):522-5.

[109] Rabat et al., “Sequences of Proteins of Immunological Interest”, Fifth Edition, U.S. Department of Health and Human Services, 1991; NIH Publication No. 91-3242

[110] Kostelny et al., “Formation of a bispecific antibody by the use of leucine zippers”. J Immunol. 1992 Mar 1 ; 148(5): 1547-53.

[111] Paul et al., “Fundamental immunology”. Philadelphia : Wolters Kluwer Health/Lippincott Williams & Wilkins, 2013.

[112] Queens et al., “A humanized antibody that binds to the interleukin 2 receptor”. Proc Natl Acad Sci U S A. 1989 Dec; 86(24): 10029-10033.

[113] Riechmann et al., “Reshaping human antibodies for therapy”, 1998, 332(6162):323-7

[114] Sambrook J et al., “Molecular Cloning: A Laboratory Manual”, Third Edition, 2000.

[115] Songsivilai & Lachmarm, “Bispecific antibody: a tool for diagnosis and treatment of disease”. Clin Exp Immunol. 1990 Mar; 79(3): 315-321.

[116] Tomlinson et al. (1992) "The Repertoire of Human Germline VH Sequences Reveals about Fifty Groups of VH Segments with Different Hypervariable Loops" J. Mol. Biol. 227:776-798

[117] Ward et al., “Binding activities of a repertoire of single immunoglobulin variable domains secreted from Escherichia coli”, Nature 341, 544-546 (1989)

SEQUENCE LISTING

Clone# 1C9-1C9

Amino Acids

Heavy chain:

VQLQESGPGLVKPSQSLSLTCTVTGYSITTDYAWNWIRQFPGNKLECMGYINYSGSTSF NPS LKS RIS ITRDTS KN QFFLQLN S VTTEDT AT Y Y C ARWD Y GRGGS YAMD Y W GQGTS V TVSS (SEQ ID NO:l)

Light chain:

IVLTQSPASLAVSLGQRATISCRASESVDSYGNSFMHWYQQKPGQPPKLLIYLASNLESG VP ARF S GS GS RTDFTLTIDP VE ADD A AT Y Y C QQNNEDPWTF GGGTKLEIK (SEQ ID NO:2)

Heavy Chain CDRs CDR1

GYSITTDYA (SEQ ID NOG)

CDR2

INYSGST (SEQ ID NO:4)

CDR3

ARWD Y GRGGS YAMD Y (SEQ ID NOG)

Light Chain CDRs CDR1

ESVDSYGNSF (SEQ ID NOG)

CDR2

LAS (SEQ ID NOG)

CDR3

QQNNEDPWT (SEQ ID NOG) Nucleotide:

Heavy chain:

GTA CAA CTG CAA GAA AGT GGG CCA GGC TTG GTG AAG CCT TCA CAG TCA TTG TCA CTG ACG TGT ACC GTG ACT GGC TAC TCT ATT ACT ACC GAC TAT GCG TGG AAT TGG ATC AGA CAA TTC CCC GGA AAC AAG CTC GAA TGC ATG GGT TAC ATA AAT TAT TCC GGT TCA ACT TCT TTT AAT CCT AGT CTG AAG TCC AGG ATT AGC ATC ACG AGG GAT ACC TCA AAA AAT CAA TTT TTC CTG CAA CTG AAT AGC GTG ACC ACC GAG GAC ACG GCG ACG TAC TAT TGC GCC AGG TGG GAT TAC GGA AGG GGA GGC AGC TAC GCA ATG GAT TAC TGG GGG CAG GGG ACG TCC GTC ACG GTA AGC AGC (SEQ ID NO:9)

Light chain:

ATT GTT CTG ACC CAG TCA CCG GCC AGT CTT GCT GTT TCA CTC GGC CAG AGG GCT ACT ATC TCC TGT AGG GCC AGT GAA TCC GTG GAC TCA TAC GGG AAC TCT TTT ATG CAC TGG TAC CAG CAG AAG CCC GGA CAA CCC CCA AAA CTT CTC ATC TAT CTC GCT TCT AAT CTC GAG AGC GGA GTC CCG GCG AGG TTT TCA GGG AGC GGG TCA CGC ACC GAC TTC ACG CTG ACT ATA GAC CCG GTA GAG GCC GAT GAC GCA GCT ACT TAC TAC TGT CAG CAG AAT AAT GAA GAC CCG TGG ACG TTC GGG GGC GGC ACT AAG TTG GAG ATT AAG (SEQ ID NO: 10)

Heavy Chain CDRs

CDR1

GGC TAC TCT ATT ACT ACC GAC TAT GCG (SEQ ID NO: 11)

CDR2

ATA AAT TAT TCC GGT TCA ACT (SEQ ID NO: 12)

CDR3

GCC AGG TGG GAT TAC GGA AGG GGA GGC AGC TAC GCA ATG GAT TAC

(SEQ ID NO: 13) Light Chain CDRs

CDR1

GAA TCC GTG GAC TCA TAC GGG AAC TCT TTT (SEQ ID NO: 14) CDR2

CTC GCT TCT (SEQ ID NO: 15)

CDR3

CAG CAG AAT AAT GAA GAC CCG TGG ACG (SEQ ID NO: 16)

Clone# 3F4-1C2 Amino Acids Heavy chain:

VQLQQSGPDLVKPGASVKMSCKASGYTFTSYVMHWVKQKPGQGLEWIGYINPYNDN TRYNEKFKGKATLT S DKS S S T A YMELS S LTS EDS A V Y Y C AN Y Y GSNF AMD YW GQGT S VTVSS (SEQ ID NO: 17)

Light chain:

DIQMTQTTS S LS AS LGDRVTISCRAS QDISNYLTW Y QQKPDGT VKLLIY YTSRLHS GVPS RFS GS GS GTD Y S LTIN S LDQEDIATYFCQQGSTLPWTFGGGTKVEIK (SEQ ID NO: 18)

Heavy Chain CDRs

CDR1

GYTFTSYV (SEQ ID NO: 19)

CDR2

INPYNDNT (SEQ ID NO:20)

CDR3

ANYY GSNFAMD Y (SEQ ID NO:21) Light Chain CDRs

CDR1

QDISNY (SEQ ID NO:22)

CDR2

YTS (SEQ ID NO:23)

CDR3

QQGSTLPWT (SEQ ID NO:24)

Nucleotide:

Heavy chain:

GTA CAA CTC CAA CAG AGC GGT CCC GAC CTC GTT AAA CCC GGT GCA TCA GTC AAG ATG TCT TGC AAA GCG AGC GGT TAC ACC TTC ACG TCC TAT GTG ATG CAT TGG GTA AAA CAA AAG CCA GGG CAA GGA CTT GAA TGG ATT GGC TAC ATA AAC CCG TAT AAC GAT AAC ACG AGG TAC AAC GAA AAA TTC AAA GGT AAA GCC ACA TTG ACT TCC GAT AAA TCT AGT TCT ACC GCG TAT ATG GAA CTG TCC AGC CTG ACT TCT GAG GAC AGT GCC GTG TAT TAC TGT GCC AAT TAT TAC GGC TCT AAC TTC GCT ATG GAC TAC TGG GGG CAG GGC ACG AGT GTA ACA GTA TCC TCC (SEQ ID NO:25)

Light chain:

GAC ATA CAG ATG ACC CAA ACT ACC TCA TCT CTG TCA GCT TCA CTG GGA GAC CGA GTG ACG ATC TCC TGC CGC GCT AGT CAA GAT ATC TCC AAC TAT CTG ACT TGG TAT CAG CAA AAG CCA GAC GGG ACA GTA AAG CTG CTC ATT TAT TAT ACC TCA AGA CTC CAC AGT GGA GTT CCA AGC AGG TTC AGC GGA AGC GGA TCT GGG ACA GAC TAC TCA CTC ACA ATC AAC AGT TTG GAC CAG GAG GAC ATA GCC ACC TAT TTT TGT CAG CAA GGA TCT ACC CTG CCT TGG ACT TTT GGG GGC GGA ACG AAG GTT GAA ATT AAG (SEQ ID NO:26)

Heavy Chain CDRs CDR1

GGT TAC ACC TTC ACG TCC TAT GTG (SEQ ID NO:27)

CDR2

ATA AAC CCG TAT AAC GAT AAC ACG (SEQ ID NO:28)

CDR3

GCC AAT TAT TAC GGC TCT AAC TTC GCT ATG GAC TAC (SEQ ID NO:29)

Light Chain CDRs

CDR1

CAA GAT ATC TCC AAC TAT (SEQ ID NO:30)

CDR2

TAT ACC TCA (SEQ ID NOG 1)

CDR3

CAG CAA GGA TCT ACC CTG CCT TGG ACT (SEQ ID NO:32)

Clone# 2D12-5F11

Amino Acids

Heavy chain:

VQLQESGPGLVKPSQSLSLTCTVTGYSITSDYAWNWIRQFPGNKLEWMGYISYSGSTSY NPS LKS RIS ITRDTS KN QFFLQLN S VTTEDT AT Y Y C ARWAFGRGGS YAMD YW GQG AS V TVSS (SEQ ID NO:33)

Light chain: IVLTQS P AS LAV S LGQRATIS CR AS ENVDS Y GNSFMHW Y QQKPGQPPKLLIYL AS NLES GVPARFSGSGSRTDFTLTIDPVEADDAATYYCQQNNEDPWTFGGGTKLEIK (SEQ ID NO:34)

Heavy Chain CDRs CDR1

GYSITSDYA (SEQ ID NO:35)

CDR2

ISYSGST (SEQ ID NO:36)

CDR3

ARWAFGRGGSYAMDY (SEQ ID NO:37)

Light Chain CDRs CDR1

ENVDS YGNSF (SEQ ID NO:38)

CDR2

LAS (SEQ ID NO:39)

CDR3

QQNNEDPWT (SEQ ID NO:40)

Nucleotide:

Heavy chain:

GTG CAA CTC CAA GAA AGT GGG CCT GGA CTC GTC AAA CCT AGT CAA AGC CTG AGT CTT ACA TGT ACC GTG ACA GGC TAC TCT ATA ACG AGC GAC TAT GCG TGG AAC TGG ATT CGG CAG TTT CCG GGG AAC AAA CTT GAG TGG ATG GGG TAC ATC TCC TAC TCT GGT AGC ACG AGC TAC AAC CCT AGT TTG AAG TCC CGC ATA AGT ATT ACA CGC GAT ACG AGC AAA AAC CAA TTC TTC CTT CAG TTG AAC TCT GTG ACT ACT GAG GAT ACC GCA ACA TAC TAT TGC GCG AGG TGG GCT TTC GGA AGA GGA GGC TCA TAC GCA ATG GAT TAT TGG GGA CAA GGA GCA AGT GTA ACC GTC TCT AGT (SEQ ID NO:41)

Light chain:

ATA GTC TTG ACT CAA TCT CCC GCG TCT CTC GCG GTT TCT CTC GGG CAA AGG GCG ACT ATC TCA TGC AGG GCG TCC GAA AAC GTC GAC TCC TAT GGT AAT TCA TTT ATG CAC TGG TAT CAA CAG AAG CCT GGG CAA CCA CCT AAA CTG CTG ATA TAT TTG GCA AGT AAT CTG GAA TCT GGC GTG CCA GCA AGA TTT AGC GGG TCA GGG AGC CGG ACG GAC TTT ACC CTC ACT ATT GAC CCA GTC GAA GCC GAC GAT GCC GCT ACC TAT TAC TGC CAA CAA AAT AAT GAG GAT CCC TGG ACT TTT GGG GGC GGC ACT AAA CTT GAG ATA AAA (SEQ ID NO:42)

Heavy Chain CDRs

CDR1

GGC TAC TCT ATA ACG AGC GAC TAT GCG (SEQ ID NO:43)

CDR2

ATC TCC TAC TCT GGT AGC ACG (SEQ ID NO:44)

CDR3

GCG AGG TGG GCT TTC GGA AGA GGA GGC TCA TAC GCA ATG GAT TAT

(SEQ ID NO:45)

Light Chain CDRs

CDR1

GAA AAC GTC GAC TCC TAT GGT AAT TCA TTT (SEQ ID NO:46)

CDR2

TTG GCA AGT (SEQ ID NO:47)

CDR3

CAA CAA AAT AAT GAG GAT CCC TGG ACT (SEQ ID NO:48)

Claims

Claims

WE CLAIM:

1. An isolated monoclonal antibody, or antigen -binding portion thereof, comprising

(a) a heavy chain variable region CDR1 comprising SEQ ID NO:3;

(b) a heavy chain variable region CDR2 comprising SEQ ID NO:4;

(c) a heavy chain variable region CDR3 comprising SEQ ID NO:5;

(d) a light chain variable region CDR1 comprising SEQ ID NO:6;

(e) a light chain variable region CDR2 comprising Leu-Ala-Ser (SEQ ID NO:7); and

(f) a light chain variable region CDR3 comprising SEQ ID NO:8, wherein said antibody or portion specifically binds to human 0X40 and activates 0X40 signaling thereby contributing to T cell-mediated immunity.

2. An isolated monoclonal antibody, or antigen-binding portion thereof, comprising

(a) a heavy chain variable region CDR1 comprising SEQ ID NO: 19;

(b) a heavy chain variable region CDR2 comprising SEQ ID NO:20;

(c) a heavy chain variable region CDR3 comprising SEQ ID NO:21;

(d) a light chain variable region CDR1 comprising SEQ ID NO:22;

(e) a light chain variable region CDR2 comprising Tyr-Thr-Ser (SEQ ID NO:23); and

(f) a light chain variable region CDR3 comprising SEQ ID NO:24, wherein said antibody or portion specifically binds to human 0X40 and activates 0X40 signaling thereby contributing to T cell-mediated immunity.

3. An isolated monoclonal antibody, or antigen-binding portion thereof, comprising:

(a) a heavy chain variable region CDR1 comprising SEQ ID NO:35;

(b) a heavy chain variable region CDR2 comprising SEQ ID NO:36; (c) a heavy chain variable region CDR3 comprising SEQ ID NO:37;

(d) a light chain variable region CDR1 comprising SEQ ID NO:38;

(e) a light chain variable region CDR2 comprising Leu-Ala-Ser (SEQ ID NO:39) ; and

(f) a light chain variable region CDR3 comprising SEQ ID NO:40, wherein said antibody or portion specifically binds to human 0X40 and activates 0X40 signaling thereby contributing to T cell-mediated immunity.

4. The antibody or antigen-binding portion according to any one of claims 1 -3 that comprises a Fab fragment, an F(ab')2 fragment, an Fv fragment, a single chain antibody, or a bispecific antibody.

5. A pharmaceutical composition comprising the antibody or antigen-binding portion- according to any one of claims 1-3 and a pharmaceutically acceptable carrier.

6. A method of treating cancer in a human, comprising the step of administering to the human the antibody or antigen-binding portion according to any one of claims 1-3 in an amount effective to treat said cancer.

7. A method of enhancing an immune response in a subject in need thereof, comprising the step of administering to the subject an effective amount of the antibody or antigen-binding portion according to any one of claims 1-3, wherein said response is indicated by activation of 0X40 signaling that contributes to T cell-mediated immunity.

8. The monoclonal antibody, or an antigen-binding portion thereof of any one of claims 1-3, wherein the antibody stimulates an anti-tumor immune response.

9. An isolated monoclonal antibody, or antigen-binding portion thereof, comprising:

(a) a heavy chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 1, 17 and 33; and

(b) a light chain variable region comprising an amino acid sequence selected from the group consisting of SEQ ID NOs: 2, 18 and 34; wherein said antibody or portion specifically binds to human 0X40 and activates 0X40 signaling thereby contributing to T cell-mediated immunity

10. A monoclonal antibody or an antigen-binding portion thereof according to claim 9, wherein the heavy chain variable domain comprising SEQ ID NO:l and the light chain variable domain comprising SEQ ID NO:2,

11. A monoclonal antibody or an antigen-binding portion thereof according to claim 9, wherein the heavy chain variable domain comprising SEQ ID NO: 17 and the light chain variable domain comprising SEQ ID NO: 18.

12. A monoclonal antibody or an antigen-binding portion thereof according to claim 9, wherein the heavy chain variable domain comprising SEQ ID NO:33 and the light chain variable domain comprising SEQ ID NO:34.

13. The antibody or antigen-binding portion according to any one of claims 9-12 that comprises a Fab fragment, an F(ab')2 fragment, an Fv fragment, a single chain antibody, or a bispecific antibody.

14. A pharmaceutical composition comprising the antibody or antigen-binding portion- according to any one of claims 9-13 and a pharmaceutically acceptable carrier.

15. A method of treating cancer in a human, comprising the step of administering to the human the antibody or antigen-binding portion according to any one of claims 9-13 in an amount effective to treat said cancer.

16. A method of enhancing an immune response in a subject in need thereof, comprising the step of administering to the subject an effective amount of the antibody or antigen-binding portion according to any one of claims 9-13, wherein said response is indicated by activation of antigen presenting cells in the subject in need thereof.

17. The antibody of any one of claims 9-13, wherein the antibody stimulates an anti-tumor immune response.

18. The antibody according to any one of claims 9-13, that comprises an immunoglobulin G (IgG), an IgM, an IgE, an IgA or an IgD molecule.

19. The monoclonal antibody according to claim 18, wherein said antibody comprises a chimeric antibody or humanized antibody.

20. The monoclonal antibody according to claim 18, wherein said antibody comprises an IgGl, IgG2, IgG3, or IgG4.

21. A monoclonal antibody or an antigen-binding portion thereof according to claim 9, wherein said antibody comprises: a heavy chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NO:9 and a light chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NO: 10.

27. A monoclonal antibody or an antigen-binding portion thereof according to claim 9, wherein said antibody comprises: a heavy chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NO:25 and a light chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NO:26.

28. A monoclonal antibody or an antigen-binding portion thereof according to claim 9, wherein said antibody comprises: a heavy chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NO:41 and a light chain variable domain amino acid sequence encoded by a nucleic acid sequence comprising SEQ ID NO:42.

29. An immunoconjugate comprising the antibody or portion according to any one of claims 1-3.

30. A bispecific antibody comprising the antibody or portion according to any one of claims 1-3.

31. The monoclonal antibody or antigen-binding portion in any one of claims 1-3 comprising at least two-F(ab) regions capable of specific binding to human 0X40 and activates 0X40 signaling thereby contributing to T cell-mediated immunity

32. A bispecific or muti-specific antibody comprising an antibody or portion binding to CTLA-4 and the antibody or portion according to any one of claims 1-3.

33. A bispecific or muti-specific antibody comprising an antibody or portion binding to CD40 and the antibody or portion according to any one of claims 1-3.

34. An immunoconjugate comprising a CpG oligodeoxynucleotide and the antibody or portion according to any one of claims 1-3.