WO2023081915A1

WO2023081915A1 - Il-8 as a predictive biomarker and methods of use thereof for the treatment of cancer

Info

Publication number: WO2023081915A1
Application number: PCT/US2022/079466
Authority: WO
Inventors: Raphael Clynes; Catherin Aversa FLEENER; Ying Ding
Original assignee: Xencor, Inc.
Priority date: 2021-11-08
Filing date: 2022-11-08
Publication date: 2023-05-11

Abstract

The present disclosure is directed to methods for treating a solid cancerous tumor by measuring a biomarker level in a sample from a human subject having the solid cancerous tumor to identify the subject as having a responder phenotype, and administering a bispecific anti-PDl x anti-CTLA4 antibody to the subject having the responder phenotype.

Description

IL-8 AS A PREDICTIVE BIOMARKER AND METHODS OF USE THEREOF FOR

THE TREATMENT OF CANCER

PRIORITY CLAIM

[0001] This application claims priority to and benefit of United States Provisional Application No. 63/276,946, filed on November 8, 2021, the contents of which are hereby incorporated by reference in their entirety.

SEQUENCE LISTING

[0002] The instant application contains a Sequence Listing which has been submitted electronically in XML format and is hereby incorporated by reference in its entirety. Said XML copy, created on November 7, 2022, is named 067461-5295-WO.xml and is 4,836 bytes in size.

FIELD

[0003] The present disclosure generally relates to methods for treating a solid cancerous tumor by administering a bispecific anti-PDl x anti-CTLA4 antibody.

BACKGROUND

[0004] The discovery of CTLA4 and PD1 resulted in the first therapeutic checkpoint inhibitors, monoclonal antibodies designed to interact with these receptors, blocking their capacity to downregulate cytotoxic T-cell destruction of malignant cells. Indeed, beginning with the FDA approval of an anti-CTLA4 antibody, ipilimumab, for the treatment of advanced melanoma in 2011, the ensuing years have seen a long list of FDA approvals from the use of checkpoint immuno-oncology antibodies in a number of cancer indications.

[0005] One approach to optimizing a checkpoint therapy is a combination therapy of two checkpoint inhibitors. Indeed, while administering two separate checkpoint inhibitor antibodies in a single treatment regimen is one way to achieve the net effect of targeting and suppressing both checkpoint pathways, there are other, perhaps better, ways to accomplish dual checkpoint targeting. For example, a bispecific monoclonal antibody such as XmAb717, which binds both PD1 and CTLA4 receptors, should be able to block both pathways. However, not all patients may respond to dual checkpoint targeting.

[0006] Accordingly, there is a need for improved methods of delivering XmAb717 to human subjects who possess solid cancerous tumors and can benefit from XmAb717 therapy.

SUMMARY

[0007] The present disclosure generally relates to methods for treating a solid cancerous tumor by measuring a biomarker level in a sample from a human subject having the solid cancerous tumor to identify the subject as having a responder phenotype and administering a bispecific anti-PDl x anti-CTLA4 antibody to the subject having the responder phenotype.

[0008] In one aspect, the invention provides a method for treating a solid cancerous tumor in a human subject, comprising: (a) measuring a biomarker level in a sample from the human subject having the solid cancerous tumor to identify the subject as having a responder phenotype; and (b) administering a bispecific antibody to the subject having the responder phenotype; wherein the bispecific antibody comprises a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3.

[0009] In one aspect, the invention provides a method for treating a solid cancerous tumor in a human subject, comprising: administering a bispecific antibody to the subject; wherein the bispecific antibody comprises a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3; and wherein a sample from the subject has a biomarker level that identifies the subject as a responder phenotype to the bispecific antibody. [0010] In one aspect, the invention provides a method selecting a subject for treatment with a bispecific antibody that comprises a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3, the method comprising: measuring a biomarker level in a sample from the human subject having the solid cancerous tumor to identify the subject as having a responder phenotype.

[0011] In one aspect, the invention provides a bispecific antibody product comprising: a) a bispecific antibody that comprises a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3; and b) a label providing that the bispecific antibody is indicated for use in a human subject having a responder phenotype, wherein the responder phenotype is identified by a biomarker level in a sample from the subject.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] FIG. 1 depicts the structure of the antibody described herein. The XmAb717 has a "bottle opener" format (also referred to as the “triple F” format). Bottle opener format antibodies include a) a first monomer that includes a first Fc domain and an scFv region, wherein the scFv includes a first variable heavy chain and a first variable light chain (also referred herein as a “scFv-Fc heavy chain”); b) a second monomer that includes a VH-CH1- hinge-CH2-CH3, wherein VH is a second variable heavy chain and CH2 and CH3 is a second Fc domain (also referred herein as a “Fab-Fc heavy chain”); and c) a light chain that includes a second variable light chain. As shown in FIG. 1, the scFv is the PD-1 binding domain and the second variable heavy chain and second variable light chain for the CTLA4 binding domain.

[0013] FIG. 2 depicts the amino acid sequences of the XmAb717 antibody. The antibody is named using the Fab variable region first and the scFv variable region second, separated by a dash, followed by the chain designation (Fab-Fc heavy chain, scFv-Fc heavy chain or light chain). CDRs are underlined and slashes indicate the border(s) of the variable regions.

[0014] FIG. 3 depicts best percentage change from baseline in sum of diameters of target lesions in efficacy evaluable patients with measurable disease and follow-up RECIST assessments (n = 70). “Other” includes cervical cancer, cholangiocarcinoma, chondrosarcoma, gastric cancer, Leydig tumor, high-grade neuroendocrine tumor, parotid adenocarcinoma, squamous cell carcinoma of anus, and TNBC.

[0015] FIG. 4A-4C depicts baseline interleukin concentration in serum of CR/PR vs SD/PD patientsFIG. 4B depicts baseline IL- 10 in serum of CR/PR vs SD/PD patients. FIG. 4C depicts baseline IL-6 in serum of CR/PR vs SD/PD patients. Baseline serum levels of IL- 8, IL- 10 and IL-6 trended lower in patients that achieved a CR/PR on study. Serum analytes were measured using the human MAP immunoassay platform (Myriad RBM).

[0016] FIG. 5A-5C depicts the progression-free survival (PFS), time on treatment (ToT), and overall survival (OS) curves for patients stratified by biomarker IL-8) serum concentration (median cut-off at 23 pg/mL) and treated with Xmab20717. FIG. 5A depicts PFS stratified by biomarker interleukin-8 (IL-8)- serum with median cut-off at 23 pg/mL in patients treated with Xmab20717. FIG. 5B depicts ToT stratified by biomarker interleukin-8 (IL-8)- serum with median cut-off at 23 pg/mL in patients treated with Xmab20717. FIG. 5C depicts OS stratified by biomarker interleukin-8 (IL-8)- serum with median cut-off at 23 pg/mL in patients treated with Xmab20717.

[0017] FIG. 6 depicts baseline gene expression from the 10360 panel evaluated in CR/PR (n=7) vs. SD/PD patients (n=18). [0018] FIG. 7A depicts baseline CXCL8 (IL-8) in tumor samples from CR/PR vs SD/PD patients. FIG. 7B depicts baseline CXCL3 (MIP2B) in tumor samples from CR/PR vs SD/PD patients. Low CXCL8 and CXCL3 was associated with clinical benefit.

[0019] FIG. 8A depicts absolute change in the frequency (%) of ki67+ T cells from baseline. FIG. 8B depicts absolute change in the frequency (%) of ICOS+ T cells from baseline.

[0020] FIGs. 9A and 9B depict mRNA profiling of FFPE tumor biopsies performed using the nCounter® PanCancer IO 360™ Panel. FIG. 9A depicts 10360 individual genes. FIG. 9B depicts 10360 gene scores.

[0021] FIG. 10A-10C depict the overall survival (OS) for melanoma, NSCLC, or CRPC patients stratified by a high or low level of biomarker IL-8 in their serum. FIG. 10A depicts the association of the level of CXCL8 (IL-8) in serum with overall survival (OS) of melanoma patients. FIG. 10B depicts the association of the level of CXCL8 (IL-8) in serum with overall survival (OS) in non-small cell lung carcinoma (NSCLC) patients. FIG. 10C depicts the association of the level of CXCL8 (IL-8) in serum with overall survival (OS) in CRPC patients.

[0022] FIG. 11 depicts the response rate of cancer patients (castrate resistant adenocarcinoma of the postrate, melanoma, non-small cell lung carcinoma (NSCLC), ovarian or fallopian tube carcinoma and renal cell carcinoma (clear cell predominant type) patients) to treatment with Xmab20717 that are IL-8 biomarker positive (<23 pg/ml IL-8) or biomarker negative (>23pg/ml IL-8). Shown for each cancer is the response rate for all patients, the response rate for patients that are IL-8 biomarker positive (<23 pg/ml IL-8), and the response rate for patients that are biomarker negative (>23 pg/ml IL-8). [0023] FIG. 12: depicts the overall response rate (ORR) baseline CXCL8 (IL-8) in serum of CR/PR vs SD/PD patients.

[0024] FIG. 13A-C: depict the CXCL8 (IL-8) patient level associations between overall response rate (ORR), progression free-survival (PFS), the time on treatment (ToT) survival curve and overall survival (OS). FIG. 13A depicts the progression-free survival (PFS) stratified by biomarker CXCL8 (IL-8) serum with cutoff: 0.117. FIG. 13B depicts the time on treatment (ToT) survival curve stratified by CXCL8 (IL-8) serum with cut-off at 0.147. FIG. 13C depicts the overall survival (OS) stratified by biomarker CXCL8 (IL-8) serum with cut-off at 0.147

DETAILED DESCRIPTION

Definitions

[0025] Such definitions are meant to encompass grammatical equivalents.

[0026] By “CTLA4,” “CTLA-4,” “cytotoxic T-lymphocyte-associated protein 4,” “CD 152,” or “cluster of differentiation 152” (e.g., Genebank Accession Number

NP_001032720 (human isoform without transmembrane) and NP_005205 (human isoform with transmembrane)) as used herein is meant a coinhibitory receptor that is present on the surface of CD4+ and CD8+ T cells that is upregulated in inflammatory environments in which activated T cells are present. CTLA4 is a member of the immunoglobulin superfamily. CTLA4 contains an extracellular V domain, a transmembrane domain, and a cytoplasmic tail. Alternate splice variants, encoding different isoforms, have been characterized. The membrane-bound isoform functions as a homodimer interconnected by a disulfide bond, while the soluble isoform functions as a monomer. CTLA4 is capable of providing a physiological counterbalance to immune cell activation and thereby to control the intensity of the immune response. It exerts this effect by outcompeting CD28, a costimulatory molecule necessary for T-cell activation, for binding to CD80 and CD86 on antigen-presenting cells and tumor cells. The net effect of CTLA4 up-regulation is down-modulation of T-cell activation (Postow et al., J Clin Oncol. 2015;33(17): 1974-1982). CTLA4 can also inhibit T cell responses directly via SHP-2 and PP2A dephosphorylation of TCR-proximal signaling proteins such as CD3 and LAT. CTLA4 is also known to bind PI3K.

[0027] By “PD1,” “PD-1,” “Programmed cell death protein 1,” “CD279,” and “cluster of differentiation 279” (e.g., Genebank Accession Number NP_0015009 (human)) as used herein is meant a type I membrane protein that is a member of the extended CD28/CTLA-4 family of T cell regulators. PD1 includes an extracellular IgV domain followed by a transmembrane region and an intracellular tail. PD1 is expressed on the surface of activated T cells, B cells and macrophage and is upregulated in the context of chronic and persistent antigen stimulation. In human subjects with cancer, PD1 is upregulated on the surface of activated tumor-infiltrating CD8+ T cells, as well as activated B cells and myeloid cells. Its primary ligands, PDL1 and PDL2, may be expressed on a wide range of cell types including antigen-presenting cells and tumor cells, and the overall effect of engagement of the ligands is to limit, terminate, or attenuate the cytotoxic and cytokine-producing capacity of cytotoxic T cells. This, in turn, results in an ineffective antitumor immune response and the persistence of tumors (Postow et al., J Clin Oncol. 2015;33(17): 1974-1982).

[0028] By “antigen binding domain” or “ABD” herein is meant a set of six Complementary Determining Regions (CDRs) that, when present as part of a polypeptide sequence, specifically binds a target antigen as discussed herein. Thus, a “checkpoint antigen binding domain” binds a target checkpoint antigen as outlined herein. As is known in the art, these CDRs are generally present as a first set of variable heavy CDRs (vhCDRs or VHCDRs) and a second set of variable light CDRs (vlCDRs or VLCDRs), each comprising three CDRs: vhCDRl, vhCDR2, vhCDR3 for the heavy chain and vlCDRl, vlCDR2 and vlCDR3 for the light. The CDRs are present in the variable heavy and variable light domains, respectively, and together form an Fv region. Thus, in some cases, the six CDRs of the antigen binding domain are contributed by a variable heavy and a variable light domain. In a “Fab” format, the set of 6 CDRs are contributed by two different polypeptide sequences, the variable heavy domain (vh or VH; containing the vhCDRl, vhCDR2 and vhCDR3) and the variable light domain (vl or VL; containing the vlCDRl, vlCDR2 and vlCDR3), with the C-terminus of the vh domain being attached to the N-terminus of the CHI domain of the heavy chain and the C-terminus of the vl domain being attached to the N-terminus of the constant light domain (and thus forming the light chain). In a scFv format, the vh and vl domains are covalently attached, generally through the use of a linker (a “scFv linker”) as outlined herein, into a single polypeptide sequence, which can be either (starting from the N- terminus) vh-linker-vl or vl-linker-vh, with the former being generally preferred (including optional domain linkers on each side, depending on the format used (e.g., from FIG. 1). In general, the C-terminus of the scFv domain is attached to the N-terminus of the hinge in the second monomer.

[0029] By "Fab" or "Fab region" as used herein is meant the polypeptide that comprises the VH, CHI, VL, and CL immunoglobulin domains, generally on two different polypeptide chains (e.g., VH-CH1 on one chain and VL-CL on the other). Fab may refer to this region in isolation, or this region in the context of a bispecific antibody of the invention. In the context of a Fab, the Fab comprises an Fv region in addition to the CHI and CL domains.

[0030] By "Fv" or "Fv fragment" or "Fv region" as used herein is meant a polypeptide that comprises the VL and VH domains of an ABD. Fv regions can be formatted as both Fabs (as discussed above, generally two different polypeptides that also include the constant regions as outlined above) and scFvs, where the vl and vh domains are combined (generally with a linker as discussed herein) to form an scFv.

[0031] By “single chain Fv” or “scFv” herein is meant a variable heavy domain covalently attached to a variable light domain, generally using a scFv linker as discussed herein, to form a scFv or scFv domain. A scFv domain can be in either orientation from N- to C-terminus (vh-linker-vl or vl -linker- vh). In the sequences depicted in the sequence listing and in the figures, the order of the vh and vl domain is indicated in the name, e.g. H.X L.Y means N- to C-terminal is vh-linker-vl, and L.Y H.X is vl-linker-vh.

[0032] By “Fc” or “Fc region” or “Fc domain” as used herein is meant the polypeptide comprising the CH2-CH3 domains of an IgG molecule, and in some cases, inclusive of the hinge. In EU numbering for human IgGl, the CH2-CH3 domain comprises amino acids 231 to 447, and the hinge is 216 to 230. Thus, the definition of “Fc domain” includes both amino acids 231-447 (CH2-CH3) or 216-447 (hinge-CH2-CH3), or fragments thereof. An “Fc fragment” in this context may contain fewer amino acids from either or both of the N- and C- termini but still retains the ability to form a dimer with another Fc domain or Fc fragment as can be detected using standard methods, generally based on size (e.g., non-denaturing chromatography, size exclusion chromatography, etc.). Human IgG Fc domains are of particular use in the present invention, and can be the Fc domain from human IgGl, IgG2 or IgG4.

[0033] By “heavy chain constant region” herein is meant the CHl-hinge-CH2-CH3 portion of an antibody (or fragments thereof), excluding the variable heavy domain; in EU numbering of human IgGl this is amino acids 118-447. By “heavy chain constant region fragment” herein is meant a heavy chain constant region that contains fewer amino acids from either or both of the N- and C-termini but still retains the ability to form a dimer with another heavy chain constant region.

[0034] By "target antigen" as used herein is meant the molecule that is bound specifically by the antigen binding domain comprising the variable regions of a given antibody. As discussed below, in the present case the target antigens are checkpoint inhibitor proteins.

[0035] By "target cell" as used herein is meant a cell that expresses a target antigen.

[0036] By “host cell” in the context of producing a bispecific antibody according to the invention herein is meant a cell that contains the exogeneous nucleic acids encoding the components of the bispecific antibody and is capable of expressing the bispecific antibody under suitable conditions. Suitable host cells are discussed below.

[0037] By "variable region" or "variable domain" as used herein is meant the region of an immunoglobulin that comprises one or more Ig domains substantially encoded by any of the VK, V , and/or VH genes that make up the kappa, lambda, and heavy chain immunoglobulin genetic loci respectively, and contains the CDRs that confer antigen specificity. Thus, a “variable heavy domain” pairs with a “variable light domain” to form an antigen binding domain (“ABD”). In addition, each variable domain comprises three hypervariable regions (“complementary determining regions,” “CDRs”) (vhCDRl, vhCDR2 and vhCDR3 for the variable heavy domain and vlCDRl, vlCDR2 and vlCDR3 for the variable light domain) and four framework (FR) regions, arranged from amino-terminus to carboxy -terminus in the following order: FR1-CDR1-FR2-CDR2-FR3-CDR3-FR4.

[0038] The invention provides a number of antibody domains that have sequence identity to human antibody domains. Sequence identity between two similar sequences (e.g., antibody variable domains) can be measured by algorithms such as that of Smith, T.F. & Waterman, M.S. (1981) "Comparison Of Biosequences," Adv. Appl. Math. 2:482 [local homology algorithm]; Needleman, S.B. & Wunsch, CD. (1970) "A General Method Applicable To The Search For Similarities In The Amino Acid Sequence Of Two Proteins,"

J. Mol. Biol.48:443 [homology alignment algorithm], Pearson, W.R. & Lipman, D.J. (1988) "Improved Tools For Biological Sequence Comparison," Proc. Natl. Acad. Sci. (U.S.A.) 85:2444 [search for similarity method]; or Altschul, S.F. et al, (1990) "Basic Local Alignment Search Tool," J. Mol. Biol. 215:403-10, the “BLAST” algorithm, see https://blast.ncbi.nlm.nih.gov/Blast.cgi. When using any of the aforementioned algorithms, the default parameters (for Window length, gap penalty, etc) are used. In one embodiment, sequence identity is done using the BLAST algorithm, using default parameters.

[0039] The antibodies of the present invention are generally isolated or recombinant. “Isolated,” when used to describe the various polypeptides disclosed herein, means a polypeptide that has been identified and separated and/or recovered from a cell or cell culture from which it was expressed. Ordinarily, an isolated polypeptide will be prepared by at least one purification step. An “isolated antibody,” refers to an antibody which is substantially free of other antibodies having different antigenic specificities. “Recombinant” means the antibodies are generated using recombinant nucleic acid techniques in exogeneous host cells, and they can be isolated as well.

[0040] “Specific binding” or “specifically binds to” or is “specific for” a particular antigen or an epitope means binding that is measurably different from a non-specific interaction.

Specific binding can be measured, for example, by determining binding of a molecule compared to binding of a control molecule, which generally is a molecule of similar structure that does not have binding activity. For example, specific binding can be determined by competition with a control molecule that is similar to the target. [0041] Specific binding for a particular antigen or an epitope can be exhibited, for example, by an antibody having a KD for an antigen or epitope of at least about 10'⁴ M, at least about 10'⁵ M, at least about 10'⁶ M, at least about 10'⁷ M, at least about 10'⁸ M, at least about 10'⁹ M, alternatively at least about IO'¹⁰ M, at least about 10'¹¹ M, at least about 10'¹² M, or greater, where KD refers to a dissociation rate of a particular antibody-antigen interaction. Typically, an antibody that specifically binds an antigen will have a KD that is 20-, 50-, 100-, 500-, 1000-, 5,000-, 10,000- or more times greater for a control molecule relative to the antigen or epitope.

[0042] Also, specific binding for a particular antigen or an epitope can be exhibited, for example, by an antibody having a KA or Ka for an antigen or epitope of at least 20-, 50-, 100-, 500-, 1000-, 5,000-, 10,000- or more times greater for the epitope relative to a control, where KA or Ka refers to an association rate of a particular antibody-antigen interaction. Binding affinity is generally measured using a Biacore, SPR or BLI assay.

[0043] As used herein, the IC50 refers to an amount, concentration or dosage of a particular test compound that achieves a 50% inhibition of a maximal response, such as inhibition of the biological activity of PD1 and/or CTLA4, in an assay that measures such response.

[0044] As used herein, EC50 refers to a dosage, concentration or amount of a particular test compound that elicits a dose-dependent response at 50% of maximal expression of a particular response that is induced, provoked or potentiated by the particular test compound.

[0045] As used herein, the terms "treat," "treatment" and "treating" refer to the reduction or amelioration or elimination of the progression, severity and/or effect associated with a solid cancerous tumor described herein, or the increase in the immune system response of the human subject, or the amelioration of one or more symptoms (preferably, one or more discernible symptoms) of a solid cancerous tumor described herein resulting from the administration of one or more therapies. In specific embodiments, the terms "treat," "treatment" and "treating" refer to the amelioration of at least one measurable physical parameter of a solid cancerous tumor described herein, such as tumor size, rate of tumor growth, number of tumor cells, tumor invasiveness, presence of metastasis, or extent of metastasis. In other embodiments the terms "treat," "treatment" and "treating" refer to the inhibition of the progression of a solid cancerous tumor described herein, either physically by, e.g, stabilization of a discernible symptom, physiologically by, e.g, stabilization of a physical parameter, or both. In other embodiments the terms "treat," "treatment" and "treating" refer to an increase in the immune system response of the human subject, such as increased T cell infiltration, increased T cell activation, upregulation of IFN pathways, upregulation of antigen presentation pathway, increased presence of ICOS+ CD4+ T cells following ipilimumab treatment, or increased Ki67+ induction in PD1 positive T cells following treatment with pembroluzumab or nivolumab).

Overview

[0046] The invention provides methods of treating solid cancerous tumors through the administration of XmAb717 to a human subject having a biomarker as described herein.

Antibodies

[0047] The present invention is directed to the administration of XmAb717 for the treatment of particular solid cancerous tumors, as outlined herein and in U.S. Pat. App. No. 15/623,314, US Publication No. 2018/0118836, U.S. Prov. Pat. App. Nos. 62/350,145, 62/355,511, and 62/420,500, all of which are expressly incorporated herein by reference, particularly for the bispecific formats of the figures, as well as all sequences, Figures and accompanying Legends therein. [0048] In some embodiments, the bispecific anti-CTLA-4 x anti-PD-1 antibodies have a

“bottle opener” format (also referred to as the “triple F” format) as is generally depicted in FIG. 1. In this embodiment, the PD-1 antigen binding domain is the scFv in the bottle opener format and the CTLA-4 antigen binding domain is the Fab in the bottle opener format (terms as used in US Publication No. 20180118836 Al, all of which are expressly incorporated by reference in their entirety and specifically for all the definitions, sequences of CTLA-4 antigen binding domains and sequences of PD-1 antigen binding domains).

[0049] One bispecific antibody of particular use in the present invention, XmAb717, is shown in FIG. 2. In certain embodiments, XmAb717 includes a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3. XmAb717 can be made as known in the art. In certain embodiments, XmAb717 is made by expressing a nucleic acid composition that includes a) a first nucleic acid that encodes a first amino acid monomer comprising “Fab-Fc Heavy Chain”; b) a second nucleic acid that encodes a second amino acid monomer comprising “scFv-Fc Heavy Chain”; and c) a third nucleic acid that encodes a “light chain,” as depicted in FIG. 2. In some embodiments, the nucleic acids that encode for each of these three amino acid sequences can be incorporated into one or more expression vectors for expression.

[0050] As is known in the art, the nucleic acids encoding the components of the invention can be incorporated into expression vectors as is known in the art, and depending on the host cells used to produce XmAb717. Generally, the nucleic acids are operably linked to any number of regulatory elements (promoters, origin of replication, selectable markers, ribosomal binding sites, inducers, etc.). The expression vectors can be extra-chromosomal or integrating vectors. [0051] The nucleic acids and/or expression vectors of the invention are then transformed into any number of different types of host cells as is well known in the art, including mammalian, bacterial, yeast, insect and/or fungal cells, with mammalian cells (e.g., CHO cells), finding use in many embodiments.

[0052] In some embodiments, nucleic acids encoding each monomer and the optional nucleic acid encoding a light chain, as applicable depending on the format, are each contained within a single expression vector, generally under different or the same promoter controls. In embodiments of particular use in the present invention, each of these two or three nucleic acids are contained on a different expression vector.

[0053] XmAb717 can be made by culturing host cells comprising the expression vector(s) as is well known in the art. Once produced, traditional antibody purification steps are done, including an ion exchange chromatography step. As discussed in U.S. Pat. App. No.

15/623,314 and US Publication No. 2018/0118836, hereby incorporated by reference in their entirety and particularly for the discussions concerning purification, having the pls of the two monomers differ by at least 0.5 can allow separation by ion exchange chromatography or isoelectric focusing, or other methods sensitive to isoelectric point. That is, the inclusion of amino acid substitutions that alter the isoelectric point (pl) of each monomer so that such that each monomer has a different pl and the heterodimer also has a distinct pl, thus facilitating isoelectric purification of the "triple F" heterodimer (e.g., anionic exchange columns, cationic exchange columns). These substitutions also aid in the determination and monitoring of any contaminating dual scFv-Fc and mAb homodimers post-purification (e.g., IEF gels, cIEF, and analytical IEX columns).

[0054] Once made, XmAb717 can be administered to human subjects having a biomarker as described herein according to the methods and dosing regimens described herein. Pharmaceutical Compositions and Pharmaceutical A dministration

[0055] XmAb717 can be incorporated into pharmaceutical compositions suitable for administration to a human subject having a biomarker as described herein. Typically, the pharmaceutical composition comprises XmAb717 and a pharmaceutically acceptable carrier. As used herein, "pharmaceutically acceptable carrier" includes any and all solvents, dispersion media, coatings, isotonic and absorption delaying agents, and the like that are physiologically compatible and are suitable for administration to a subject for the methods described herein. Examples of pharmaceutically acceptable carriers include one or more of water, saline, phosphate buffered saline, dextrose, glycerol, ethanol and the like, as well as combinations thereof. In many cases, it will be preferable to include isotonic agents, for example, sugars, polyalcohols such as mannitol, sorbitol, or sodium chloride in the composition. Pharmaceutically acceptable carriers may further comprise minor amounts of auxiliary substances such as surfactants (such as nonionic surfactants) wetting or emulsifying agents (such as a polysorbate), preservatives or buffers (such as an organic acid, which as a citrate or an acetate), which enhance the shelf life or effectiveness of XmAb717. Examples of pharmaceutically acceptable carriers include polysorbates (polysorbate-80).

[0056] In an exemplary embodiment, the pharmaceutical composition comprises XmAb717, and a preservative or buffer. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717, and histidine. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717, and an acetate. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717, and sodium acetate. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and a citrate. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium citrate. [0057] In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and an isotonic agent. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and a polyalcohol. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and mannitol. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sorbitol. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium chloride. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and potassium chloride.

[0058] In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and a wetting or emulsifying agent. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and a polysorbate. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and polysorbate-80.

[0059] In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and an intravenous solution stabilizer. In an exemplary embodiment, the intravenous solution stabilizer comprises a polysorbate and a citrate. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium citrate and polysorbate-80.

[0060] In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and a buffer and an isotonic agent. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and a buffer and sorbitol. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and an acetate and an isotonic agent. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and histidine and an isotonic agent. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and an acetate and sorbitol. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium acetate and sorbitol. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and histidine and sorbitol.

[0061] In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and a buffer and an isotonic agent and an intravenous solution stabilizer. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and a buffer and sorbitol and an intravenous solution stabilizer. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and an acetate and an isotonic agent and an intravenous solution stabilizer. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and histidine and an isotonic agent and an intravenous solution stabilizer. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and an acetate and sorbitol and an intravenous solution stabilizer. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium acetate and sorbitol and an intravenous solution stabilizer. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and histidine and sorbitol and an intravenous solution stabilizer.

[0062] In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium chloride. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium chloride and polysorbate-80. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium citrate and sodium chloride. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium citrate, sodium chloride, and polysorbate-80. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium citrate, sodium chloride, sodium acetate, sorbitol and polysorbate-80. In an exemplary embodiment, the pharmaceutical composition comprises XmAb717 and sodium citrate, sodium chloride, histidine, sorbitol and polysorbate-80.

[0063] The pharmaceutical compositions of this invention 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 infusible solutions), dispersions or suspensions. The form depends on the intended mode of administration and therapeutic application. Exemplary compositions are in the form of injectable or infusible solutions, such as compositions similar to those used for passive immunization of humans with other antibodies. In an exemplary embodiment, the mode of administration is intravenous. In an exemplary embodiment, the antibody is administered by intravenous infusion or injection.

[0064] Pharmaceutical compositions typically must be sterile and stable under the conditions of manufacture and storage. Sterile injectable solutions can be prepared by incorporating the antibody in the required amount in an appropriate solvent with one or a combination of ingredients enumerated herein, as required, followed by filtered sterilization. Generally, dispersions are prepared by incorporating the antibody into a sterile vehicle that contains a basic dispersion medium and the required other ingredients from those enumerated herein.

[0065] XmAb717 can be administered by a variety of methods known in the art. In an exemplary embodiment, the route/mode of administration is intravenous injection. As will be appreciated by the skilled artisan, the route and/or mode of administration will vary depending upon the desired results.

Methods of Treatins Solid Cancerous Tumors

[0066] The compositions of the invention can be used to treat certain solid cancerous tumors. In an exemplary embodiment, a composition of the invention is administered according to a method of the invention to treat a solid cancerous tumor. In an exemplary embodiment, the solid cancerous tumor is receptive to treatment by an antibody which binds to PD1. In an exemplary embodiment, the solid cancerous tumor is receptive to treatment by an antibody which binds to CTLA4. In an exemplary embodiment, the solid cancerous tumor is receptive to treatment by an antibody which binds to PD1 and CTLA4.

[0067] In an exemplary embodiment, the solid cancerous tumor is melanoma. In an exemplary embodiment, the solid cancerous tumor is melanoma, excluding uveal melanoma. In an exemplary embodiment, the solid cancerous tumor is cervical cancer. In an exemplary embodiment, the solid cancerous tumor is cervical carcinoma. In an exemplary embodiment, the solid cancerous tumor is breast cancer. In an exemplary embodiment, the solid cancerous tumor is breast carcinoma. In an exemplary embodiment, the solid cancerous tumor is breast carcinoma that is estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 (HER2) negative (triple negative breast cancer [TNBC]). In an exemplary embodiment, the solid cancerous tumor is hepatocellular cancer. In an exemplary embodiment, the solid cancerous tumor is hepatocellular carcinoma. In an exemplary embodiment, the solid cancerous tumor is urothelial cancer. In an exemplary embodiment, the solid cancerous tumor is urothelial carcinoma. In an exemplary embodiment, the solid cancerous tumor is bladder cancer. In an exemplary embodiment, the solid cancerous tumor is bladder carcinoma. In an exemplary embodiment, the solid cancerous tumor is head and neck cancer. In an exemplary embodiment, the solid cancerous tumor is squamous cell carcinoma of the head and neck. In an exemplary embodiment, the solid cancerous tumor is renal cell cancer. In an exemplary embodiment, the solid cancerous tumor is renal cell carcinoma. In an exemplary embodiment, the solid cancerous tumor is clear cell predominant type renal cell carcinoma. [0068] In an exemplary embodiment, the solid cancerous tumor is colorectal cancer. In an exemplary embodiment, the solid cancerous tumor is MSI-high colorectal cancer. In an exemplary embodiment, the solid cancerous tumor is colorectal carcinoma. In an exemplary embodiment, the solid cancerous tumor is high microsatellite instability colorectal carcinoma. In an exemplary embodiment, the solid cancerous tumor is mismatch repair deficient colorectal carcinoma. In an exemplary embodiment, the solid cancerous tumor is endometrial cancer. In an exemplary embodiment, the solid cancerous tumor is MSI-high endometrial cancer. In an exemplary embodiment, the solid cancerous tumor is endometrial carcinoma. In an exemplary embodiment, the solid cancerous tumor is high microsatellite instability endometrial carcinoma. In an exemplary embodiment, the solid cancerous tumor is mismatch repair deficient endometrial carcinoma. In an exemplary embodiment, the solid cancerous tumor is small cell lung cancer. In an exemplary embodiment, the solid cancerous tumor is small cell lung carcinoma. In an exemplary embodiment, the solid cancerous tumor is nonsmall cell lung cancer. In an exemplary embodiment, the solid cancerous tumor is non-small cell lung carcinoma. In an exemplary embodiment, the solid cancerous tumor is gastric cancer. In an exemplary embodiment, the solid cancerous tumor is gastric adenocarcinoma. In an exemplary embodiment, the solid cancerous tumor is gastroesophageal junction cancer. In an exemplary embodiment, the solid cancerous tumor is gastroesophageal junction adenocarcinoma.

[0069] In an exemplary embodiment, the solid cancerous tumor is a microsatellite instability -high cancer. In an exemplary embodiment, the solid cancerous tumor is a mismatch repair deficient cancer.

[0070] In an exemplary embodiment, the solid cancerous tumor is mesothelioma. In an exemplary embodiment, the solid cancerous tumor is neuroendocrine cancer. In an exemplary embodiment, the solid cancerous tumor is high-grade neuroendocrine cancer. In an exemplary embodiment, the solid cancerous tumor is neuroendocrine carcinoma. In an exemplary embodiment, the solid cancerous tumor is anal cancer. In an exemplary embodiment, the solid cancerous tumor is anal carcinoma. In an exemplary embodiment, the solid cancerous tumor is squamous cell carcinoma of the anus.

[0071] In an exemplary embodiment, the solid cancerous tumor is prostate cancer. In an exemplary embodiment, the solid cancerous tumor is castration-resistant prostate carcinoma. In an exemplary embodiment, the solid cancerous tumor is metastatic castration-resistant prostate carcinoma. In an exemplary embodiment, the solid cancerous tumor is nasopharyngeal cancer. In an exemplary embodiment, the solid cancerous tumor is nasopharyngeal carcinoma. In an exemplary embodiment, the solid cancerous tumor is Cholangiocarcinoma. In an exemplary embodiment, the solid cancerous tumor is basal cell cancer. In an exemplary embodiment, the solid cancerous tumor is basal cell skin cancer. In an exemplary embodiment, the solid cancerous tumor is basal cell carcinoma. In an exemplary embodiment, the solid cancerous tumor is ovarian cancer. In an exemplary embodiment, the solid cancerous tumor is ovarian carcinoma. In an exemplary embodiment, the solid cancerous tumor is fallopian tube cancer. In an exemplary embodiment, the solid cancerous tumor is fallopian tube carcinoma.

[0072] In an exemplary embodiment, the solid cancerous tumor is thymus cancer. In an exemplary embodiment, the solid cancerous tumor is thymoma. In an exemplary embodiment, the solid cancerous tumor is thymic carcinoma. In an exemplary embodiment, the solid cancerous tumor is penile cancer. In an exemplary embodiment, the solid cancerous tumor is Squamous Cell Carcinoma of the Penis. In an exemplary embodiment, the solid cancerous tumor is vulvar cancer. In an exemplary embodiment, the solid cancerous tumor is vulvar carcinoma. In an exemplary embodiment, the solid cancerous tumor is solid tumors with published evidence of anti -tumor activity with anti-PDl/PDLl and/or anti-CTLA4- directed therapy. In an exemplary embodiment, the solid cancerous tumor is malignant adnexal tumor. In an exemplary embodiment, the solid cancerous tumor is malignant adnexal neoplasm. In an exemplary embodiment, the solid cancerous tumor is salivary gland cancer. In an exemplary embodiment, the solid cancerous tumor is non-squamous cell salivary gland carcinoma. In an exemplary embodiment, the solid cancerous tumor is bile duct cancer. In an exemplary embodiment, the solid cancerous tumor is bile duct carcinoma.

[0073] In an exemplary embodiment, the solid cancerous tumor is chondrosarcoma. In an exemplary embodiment, the solid cancerous tumor is Leydig tumor. In an exemplary embodiment, the solid cancerous tumor is parotid adenocarcinoma.

[0074] In an exemplary embodiment, the solid cancerous tumor is responsive to immune checkpoint inhibitor therapy.

[0075] In an exemplary embodiment, the solid cancerous tumor described herein is a primary tumor. In an exemplary embodiment, the solid cancerous tumor described herein is a metastatic tumor.

Biological and Biochemical Functionality of the Heterodimeric Checkpoint Antibodies

[0076] Generally XmAb717 is administered to human subjects with certain solid cancerous tumors, and efficacy is assessed in a number of ways as described herein. Thus, while standard assays of efficacy can be run, such as cancer load, size of tumor, evaluation of presence or extent of metastasis, etc., immuno-oncology treatments can be assessed on the basis of immune status evaluations as well. This can be done in a number of ways, including both in vitro and in vivo assays. For example, evaluation of changes in immune status (e.g., presence of ICOS+ CD4+ T cells following ipilimumab treatment) along with "old fashioned" measurements such as tumor burden, size, invasiveness, LN involvement, metastasis, etc. can be done. Thus, any or all of the following can be evaluated: the inhibitory effects of the checkpoints on CD4+ T cell activation or proliferation, CD8+ T (CTL) cell activation or proliferation, CD8+ T cell-mediated cytotoxic activity and/or CTL mediated cell depletion, NK cell activity and NK mediated cell depletion, the potentiating effects of the checkpoints on Treg cell differentiation and proliferation and Treg- or myeloid derived suppressor cell (MDSC)- mediated immunosuppression or immune tolerance, and/or the effects of the checkpoints on proinflammatory cytokine production by immune cells, e.g., IL-2, ZFN-y or TNF-a production by T or other immune cells.

[0077] In some embodiments, assessment of treatment is done by evaluating immune cell proliferation, using for example, CFSE dilution method, Ki67 intracellular staining of immune effector cells, and 3H-Thymidine incorporation method.

[0078] In some embodiments, assessment of treatment is done by evaluating the increase in gene expression or increased protein levels of activation-associated markers, including one or more of: CD25, CD69, CD137, ICOS, PD1, GITR, 0X40, and cell degranulation measured by surface expression of CD 107 A.

[0079] In general, gene expression assays are done as is known in the art.

[0080] In general, protein expression measurements are also similarly done as is known in the art.

[0081] In some embodiments, assessment of treatment is done by assessing cytotoxic activity measured by target cell viability detection via estimating numerous cell parameters such as enzyme activity (including protease activity), cell membrane permeability, cell adherence, ATP production, co-enzyme production, and nucleotide uptake activity. Specific examples of these assays include, but are not limited to, Trypan Blue or PI staining, 51Cr or 35S release method, LDH activity, MTT and/or WST assays, Calcein-AM assay, Luminescent based assay, and others.

[0082] In some embodiments, assessment of treatment is done by assessing T cell activity measured by cytokine production, measured either intracellularly or in culture supernatant using cytokines including, but not limited to, IFNy, TNFa, GM-CSF, IL2, IL6, IL4, IL5, IL10, and IL13 using well known techniques.

[0083] Accordingly, assessment of treatment can be done using assays that evaluate one or more of the following: (i) increases in immune response, (ii) increases in activation of aP and/or y6 T cells, (iii) increases in cytotoxic T cell activity, (iv) increases in NK and/or NKT cell activity, (v) alleviation of aP and/or y6 T-cell suppression, (vi) increases in pro- inflammatory cytokine secretion, (vii) increases in IL-2 secretion; (viii) increases in interferon-y production, (ix) increases in Thl response, (x) decreases in Th2 response, (xi) decreases or eliminates cell number and/or activity of at least one of regulatory T cells (Tregs).

Assays to measure efficacy

[0084] In some embodiments, T cell activation is assessed using a Mixed Lymphocyte Reaction (MLR) assay as is known in the art. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0085] In one embodiment, the signaling pathway assay measures increases or decreases in immune response as measured for example by phosphorylation or de-phosphorylation of different factors, or by measuring other post translational modifications. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein. [0086] In one embodiment, the signaling pathway assay measures increases or decreases in activation of aP and/or y6 T cells as measured for example by cytokine secretion or by proliferation or by changes in expression of activation markers like for example CD137, CD 107a, PD1, etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0087] In one embodiment, the signaling pathway assay measures increases or decreases in cytotoxic T cell activity as measured for example by direct killing of target cells like for example cancer cells or by cytokine secretion or by proliferation or by changes in expression of activation markers like for example CD137, CD107a, PD1, etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0088] In one embodiment, the signaling pathway assay measures increases or decreases in NK and/or NKT cell activity as measured for example by direct killing of target cells like for example cancer cells or by cytokine secretion or by changes in expression of activation markers like for example CD 107a, etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0089] In one embodiment, the signaling pathway assay measures increases or decreases in aP and/or y6 T-cell suppression, as measured for example by cytokine secretion or by proliferation or by changes in expression of activation markers like for example CD 137, CD 107a, PD1, etc. An increase in activity indicates immunostimulatory activity.

Appropriate increases in activity are outlined herein.

[0090] In one embodiment, the signaling pathway assay measures increases or decreases in pro-inflammatory cytokine secretion as measured for example by ELISA or by Luminex or by Multiplex bead based methods or by intracellular staining and FACS analysis or by Alispot etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0091] In one embodiment, the signaling pathway assay measures increases or decreases in IL-2 secretion as measured for example by ELISA or by Luminex or by Multiplex bead based methods or by intracellular staining and FACS analysis or by Alispot etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0092] In one embodiment, the signaling pathway assay measures increases or decreases in interferon-y production as measured for example by ELISA or by Luminex or by Multiplex bead based methods or by intracellular staining and FACS analysis or by Alispot etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0093] In one embodiment, the signaling pathway assay measures increases or decreases in Thl response as measured for example by cytokine secretion or by changes in expression of activation markers. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0094] In one embodiment, the signaling pathway assay measures increases or decreases in Th2 response as measured for example by cytokine secretion or by changes in expression of activation markers. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0095] In one embodiment, the signaling pathway assay measures increases or decreases cell number and/or activity of at least one of regulatory T cells (Tregs), as measured for example by flow cytometry or by IHC. A decrease in response indicates immunostimulatory activity. Appropriate decreases are the same as for increases, outlined herein.

[0096] In one embodiment, the signaling pathway assay measures increases or decreases in M2 macrophages cell numbers, as measured for example by flow cytometry or by IHC. A decrease in response indicates immunostimulatory activity. Appropriate decreases are the same as for increases, outlined herein.

[0097] In one embodiment, the signaling pathway assay measures increases or decreases in M2 macrophage pro-tumorigenic activity, as measured for example by cytokine secretion or by changes in expression of activation markers. A decrease in response indicates immunostimulatory activity. Appropriate decreases are the same as for increases, outlined herein.

[0098] In one embodiment, the signaling pathway assay measures increases or decreases in N2 neutrophils increase, as measured for example by flow cytometry or by IHC. A decrease in response indicates immunostimulatory activity. Appropriate decreases are the same as for increases, outlined herein.

[0099] In one embodiment, the signaling pathway assay measures increases or decreases in N2 neutrophils pro-tumorigenic activity, as measured for example by cytokine secretion or by changes in expression of activation markers. A decrease in response indicates immunostimulatory activity. Appropriate decreases are the same as for increases, outlined herein.

[0100] In one embodiment, the signaling pathway assay measures increases or decreases in inhibition of T cell activation, as measured for example by cytokine secretion or by proliferation or by changes in expression of activation markers like for example CD 137, CD 107a, PD1, etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0101] In one embodiment, the signaling pathway assay measures increases or decreases in inhibition of CTL activation as measured for example by direct killing of target cells like for example cancer cells or by cytokine secretion or by proliferation or by changes in expression of activation markers like for example CD137, CD107a, PD1, etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0102] In one embodiment, the signaling pathway assay measures increases or decreases in aP and/or y6 T cell exhaustion as measured for example by changes in expression of activation markers. A decrease in response indicates immunostimulatory activity. Appropriate decreases are the same as for increases, outlined herein.

[0103] In one embodiment, the signaling pathway assay measures increases or decreases in aP and/or y6 T cell response as measured for example by cytokine secretion or by proliferation or by changes in expression of activation markers like for example CD 137, CD 107a, PD1, etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0104] In one embodiment, the signaling pathway assay measures increases or decreases in stimulation of antigen-specific memory responses as measured for example by cytokine secretion or by proliferation or by changes in expression of activation markers like for example CD45RA, CCR7 etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein. [0105] In one embodiment, the signaling pathway assay measures increases or decreases in apoptosis or lysis of cancer cells as measured for example by cytotoxicity assays such as for example MTT, Cr release, Calcine AM, or by flow cytometry based assays like for example CFSE dilution or propidium iodide staining etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0106] In one embodiment, the signaling pathway assay measures increases or decreases in stimulation of cytotoxic or cytostatic effect on cancer cells, as measured for example by cytotoxicity assays such as for example MTT, Cr release, Calcine AM, or by flow cytometry based assays like for example CFSE dilution or propidium iodide staining etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0107] In one embodiment, the signaling pathway assay measures increases or decreases in direct killing of cancer cells as measured for example by cytotoxicity assays such as for example MTT, Cr release, Calcine AM, or by flow cytometry based assays like for example CFSE dilution or propidium iodide staining etc. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0108] In one embodiment, the signaling pathway assay measures increases or decreases in Th 17 activity as measured for example by cytokine secretion or by proliferation or by changes in expression of activation markers. An increase in activity indicates immunostimulatory activity. Appropriate increases in activity are outlined herein.

[0109] In one embodiment, the signaling pathway assay measures increases or decreases in induction of complement dependent cytotoxicity and/or antibody dependent cell-mediated cytotoxicity, as measured for example by cytotoxicity assays such as for example MTT, Cr release, Calcine AM, or by flow cytometry based assays like for example CFSE dilution or propidium iodide staining etc. An increase in activity indicates immunostimulatory activity.

Appropriate increases in activity are outlined herein.

[0110] In one embodiment, T cell activation is measured for example by direct killing of target cells like for example cancer cells or by cytokine secretion or by proliferation or by changes in expression of activation markers like for example CD137, CD107a, PD1, etc. For T-cells, increases in proliferation, cell surface markers of activation (e.g. CD25, CD69, CD137, PD1), cytotoxicity (ability to kill target cells), and cytokine production (e.g. IL-2, IL- 4, IL-6, IFNy, TNF-a, IL-10, IL-17A) would be indicative of immune modulation that would be consistent with enhanced killing of cancer cells.

[OHl] In one embodiment, NK cell activation is measured for example by direct killing of target cells like for example cancer cells or by cytokine secretion or by changes in expression of activation markers like for example CD107a, etc. For NK cells, increases in proliferation, cytotoxicity (ability to kill target cells and increases CD 107a, granzyme, and perforin expression), cytokine production (e.g. IFNY and TNF), and cell surface receptor expression (e.g. CD25) would be indicative of immune modulation that would be consistent with enhanced killing of cancer cells.

[0112] In one embodiment, y6 T cell activation is measured for example by cytokine secretion or by proliferation or by changes in expression of activation markers.

[0113] In one embodiment, Thl cell activation is measured for example by cytokine secretion or by changes in expression of activation markers.

[0114] Appropriate increases in activity or response (or decreases, as appropriate as outlined above), are increases of 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 95% or 98 to 99% percent over the signal in either a reference sample or in control samples, for example test samples that do not contain an antibody of the invention. Similarly, increases of at least one-, two-, three-, four- or five-fold as compared to reference or control samples show efficacy.

Treatments

[0115] Once made, the compositions of the invention find use in a number of solid cancerous tumor applications, generally by inhibiting the suppression of T cell activation (e.g., T cells are no longer suppressed).

[0116] Accordingly, XmAb717 finds use in the treatment of these cancers.

Dosage Regimen

[0117] In some embodiments, the XmAb717 is administered to the human subject according to a dosage regimen described herein. Dosage regimens are adjusted to provide the optimum desired response (e.g., a therapeutic or clinical response). The efficient dosages and the dosage regimens for XmAb717 depend on the disease or condition to be treated and may be determined by the persons skilled in the art.

[0118] In an exemplary embodiment, the intravenous dose of XmAb717 is administered once between about 12 and about 17 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once between about 13 and about 15 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once every 13-15 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once between about 12 and about 16 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once every 12-16 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once every 14-16 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once about every 14 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once every 14 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once about every two weeks. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once every two weeks. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once between about 13 and about 17 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once every 13-17 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once about every 15 days. In an exemplary embodiment, the intravenous dose of XmAb717 is administered once every 15 days.

[0119] In an exemplary embodiment, the administering of the intravenous dose to the human subject lasts between about 45 minutes and about 75 minutes. In an exemplary embodiment, the administering of the intravenous dose to the human subject lasts between 45 minutes and 75 minutes. In an exemplary embodiment, the administering of the intravenous dose to the human subject lasts about one hour. In an exemplary embodiment, the administering of the intravenous dose to the human subject lasts one hour.

[0120] In an exemplary embodiment, the XmAb717 is administered for a time period sufficient to treat the solid cancerous tumor. In an exemplary embodiment, the XmAb717 is administered for a time period sufficient to maintain the treatment of the solid cancerous tumor. In an exemplary embodiment, the time period is between about 1 and about 9 weeks. In an exemplary embodiment, the time period is between about 2 and about 7 weeks. In an exemplary embodiment, the time period is between about 3 and about 9 weeks. In an exemplary embodiment, the time period is between about 1 and about 8 weeks. In an exemplary embodiment, the time period is between about 3 and about 5 weeks. In an exemplary embodiment, the time period is about 4 weeks. In an exemplary embodiment, the time period is 4 weeks. In an exemplary embodiment, the time period is between about 7 and about 9 weeks. In an exemplary embodiment, the time period is about 8 weeks. In an exemplary embodiment, the time period is 8 weeks. In an exemplary embodiment, the time period is from about 1 week to about 10 years. In an exemplary embodiment, the time period is from about 1 week to about 9.5 years. In an exemplary embodiment, the time period is from about 1 week to about 9 years. In an exemplary embodiment, the time period is from about 1 week to about 8.5 years. In an exemplary embodiment, the time period is from about 1 week to about 8 years. In an exemplary embodiment, the time period is from about 1 week to about 7.5 years. In an exemplary embodiment, the time period is from about 1 week to about 7 years. In an exemplary embodiment, the time period is from about 1 week to about 6.5 years. In an exemplary embodiment, the time period is from about 1 week to about 6 years. In an exemplary embodiment, the time period is from about 1 week to about 5.5 years. In an exemplary embodiment, the time period is from about 1 week to about 5 years. In an exemplary embodiment, the time period is from about 1 week to about 4.5 years. In an exemplary embodiment, the time period is from about 1 week to about 4 years. In an exemplary embodiment, the time period is from about 1 week to about 3.5 years. In an exemplary embodiment, the time period is from about 1 week to about 3 years. In an exemplary embodiment, the time period is from about 1 week to about 2.5 years. In an exemplary embodiment, the time period is from about 1 week to about 2 years. In an exemplary embodiment, the time period is from about 1 week to about 1.5 years. In an exemplary embodiment, the time period is from about 1 week to about 1 year. In an exemplary embodiment, the time period is from about 1 week to about 3 months, or about 4 months, or about 5 months, or about 6 months, or about 7 months, or about 8 months, or about 9 months, or about 10 months or about 11 months. In an exemplary embodiment, the time period is until a positive therapeutic response is achieved. In an exemplary embodiment, the time period is as long as a positive therapeutic response is maintained. In an exemplary embodiment, the time period is until a complete response is achieved. In an exemplary embodiment, the time period is as long as until a bone marrow transplant can be performed on the human subject.

[0121] In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting between about 1 and about 9 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting between about 2 and about 7 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting between about 3 and about 9 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting between about 1 and about 8 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting between about 3 and about 5 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting about 4 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting 4 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting between about 7 and about 9 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting about 8 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting 8 weeks. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period lasting until a positive therapeutic response is achieved. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period sufficient to treat the solid cancerous tumor. In an exemplary embodiment, the XmAb717 is administered once every 13-15 days for a time period sufficient to maintain the treatment of the solid cancerous tumor. [0122] The dosage may be determined or adjusted by measuring the amount of XmAb717 of the present invention in the blood upon administration using techniques known in the art, for instance taking out a biological sample and using anti -idiotypic antibodies which target the antigen binding region of the XmAb717.

[0123] In an exemplary embodiment, the intravenous dose is between about 0.05 mg/kg and about 12 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.15 mg/kg and about 10.0 mg/kg.

[0124] In an exemplary embodiment, the intravenous dose is between about 0.05 mg/kg and about 0.25 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.07 mg/kg and about 0.23 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.09 mg/kg and about 0.21 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.11 mg/kg and about 0.19 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.13 mg/kg and about 0.17 mg/kg. In an exemplary embodiment, the intravenous dose is about 0.15 mg/kg. In an exemplary embodiment, the intravenous dose is 0.15 mg/kg.

[0125] In an exemplary embodiment, the intravenous dose is between about 0.2 mg/kg and about 0.4 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.22 mg/kg and about 0.38 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.24 mg/kg and about 0.36 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.26 mg/kg and about 0.34 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.28 mg/kg and about 0.32 mg/kg. In an exemplary embodiment, the intravenous dose is about 0.3 mg/kg. In an exemplary embodiment, the intravenous dose is 0.3 mg/kg. [0126] In an exemplary embodiment, the intravenous dose is between about 0.5 mg/kg and about 1.5 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.6 mg/kg and about 1.4 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.7 mg/kg and about 1.3 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.8 mg/kg and about 1.2 mg/kg. In an exemplary embodiment, the intravenous dose is between about 0.9 mg/kg and about 1.1 mg/kg. In an exemplary embodiment, the intravenous dose is about 1.0 mg/kg. In an exemplary embodiment, the intravenous dose is 1.0 mg/kg.

[0127] In an exemplary embodiment, the intravenous dose is between about 1.0 mg/kg and about 5.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 1.5 mg/kg and about 4.5 mg/kg. In an exemplary embodiment, the intravenous dose is between about 2.0 mg/kg and about 4.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 1.0 mg/kg and about 3.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 3.0 mg/kg and about 5.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 2.2 mg/kg and about 3.8 mg/kg. In an exemplary embodiment, the intravenous dose is between about 2.4 mg/kg and about 3.6 mg/kg. In an exemplary embodiment, the intravenous dose is between about 2.6 mg/kg and about 3.4 mg/kg. In an exemplary embodiment, the intravenous dose is between about 2.8 mg/kg and about 3.2 mg/kg. In an exemplary embodiment, the intravenous dose is between about 2.9 mg/kg and about 3.1 mg/kg. In an exemplary embodiment, the intravenous dose is about 3.0 mg/kg. In an exemplary embodiment, the intravenous dose is 3.0 mg/kg.

[0128] In an exemplary embodiment, the intravenous dose is between about 3.0 mg/kg and about 8.5 mg/kg. In an exemplary embodiment, the intravenous dose is between about 3.5 mg/kg and about 8.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 4.0 mg/kg and about 7.5 mg/kg. In an exemplary embodiment, the intravenous dose is between about 4.5 mg/kg and about 7.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 3.0 mg/kg and about 6.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 5.0 mg/kg and about 8.5 mg/kg. In an exemplary embodiment, the intravenous dose is between about 4.0 mg/kg and about 8.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 4.2 mg/kg and about 7.8 mg/kg. In an exemplary embodiment, the intravenous dose is between about 4.4 mg/kg and about 7.6 mg/kg. In an exemplary embodiment, the intravenous dose is between about 4.6 mg/kg and about 7.4 mg/kg. In an exemplary embodiment, the intravenous dose is between about 4.8 mg/kg and about 7.2 mg/kg. In an exemplary embodiment, the intravenous dose is between about 5.0 mg/kg and about 7.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 5.2 mg/kg and about 6.8 mg/kg. In an exemplary embodiment, the intravenous dose is between about 5.4 mg/kg and about 6.6 mg/kg. In an exemplary embodiment, the intravenous dose is between about 5.6 mg/kg and about 6.4 mg/kg. In an exemplary embodiment, the intravenous dose is between about 5.8 mg/kg and about 6.2 mg/kg. In an exemplary embodiment, the intravenous dose is about 6.0 mg/kg. In an exemplary embodiment, the intravenous dose is 6.0 mg/kg.

[0129] In an exemplary embodiment, the intravenous dose is between about 8.0 mg/kg and about 12.0 mg/kg. In an exemplary embodiment, the intravenous dose is between about 8.3 mg/kg and about 11.7 mg/kg. In an exemplary embodiment, the intravenous dose is between about 8.6 mg/kg and about 11.4 mg/kg. In an exemplary embodiment, the intravenous dose is between about 8.9 mg/kg and about 11.1 mg/kg. In an exemplary embodiment, the intravenous dose is between about 9.2 mg/kg and about 10.8 mg/kg. In an exemplary embodiment, the intravenous dose is between about 9.5 mg/kg and about 10.5 mg/kg. In an exemplary embodiment, the intravenous dose is between about 9.8 mg/kg and about 10.2 mg/kg. In an exemplary embodiment, the intravenous dose is about 10.0 mg/kg. In an exemplary embodiment, the intravenous dose is 10.0 mg/kg.

[0130] In some embodiments, the XmAb717 is administered intravenously. In some embodiments, the XmAb717 is administered once-every-two-weeks until disease progression, unacceptable toxicity, or individual choice.

[0131] In some embodiments, the XmAb717 is a front line therapy, second line therapy, third line therapy, fourth line therapy, fifth line therapy, or sixth line therapy.

[0132] In some embodiments, the XmAb717 treats a refractory solid cancerous tumor. In some embodiments, the XmAb717 treats a relapsed solid cancerous tumor. In some embodiments, the XmAb717 is a maintenance therapy. In some embodiments, the subject previously received anti-PD-1 therapy, anti-PDLl therapy, and/or anti-CTLA4 therapy. In some embodiments, the subject is refractory to an anti-PD-1 therapy, an anti-PDLl therapy, an anti-CTLA4 therapy, or a combination thereof. In some embodiments, the subject is relapsed to an anti-PD-1 therapy, an anti-PDLl therapy, an anti-CTLA4 therapy, or a combination thereof. In some embodiments, the subject is refractory to an anti-PD-1 therapy. In some embodiments, the subject is relapsed to an anti-PD-1 therapy. In some embodiments, the anti-PD-1 therapy is pembrolizumab, nivolumab, or a combination thereof. In some embodiments, the subject is refractory to an anti-PDLl therapy. In some embodiments, the subject is relapsed to an anti-PDLl therapy. In some embodiments, the anti-PDLl therapy is atelizumab, avelumab, or a combination thereof. In some embodiments, the subject is refractory to an anti-CTLA4 therapy. In some embodiments, the subject is relapsed to an anti-CTLA4 therapy. In some embodiments, the anti-CTLA4 therapy is ipilimumab. In some embodiments, the subject is refractory to olaparib. In some embodiments, the subject is relapsed to olaparib.

[0133] A medical professional having ordinary skill in the art may readily determine and prescribe the effective amount of the antibody composition required. For example, a physician could start doses of the medicament employed in the antibody composition at levels lower than that required in order to achieve the desired therapeutic effect and gradually increase the dosage until the desired effect is achieved.

Biomarkers

[0134] In some embodiments, XmAb717 is administered to a human subject having a biomarker as described herein that identifies the subject as a responder to XmAb717. A sample may be collected from the subject and the biomarker level in the sample may be measured using well known techniques.

[0135] In an exemplary embodiment, a biomarker level in a sample from a human subject having a solid cancerous tumor is measured to identify the subject as having a responder phenotype. In an exemplary embodiment, the sample is selected from a serum sample, a plasma sample, or a tumor sample. In an exemplary embodiment, the biomarker is a polypeptide. In an exemplary embodiment, the biomarker is a polynucleotide. In an exemplary embodiment, the biomarker is an RNA. In an exemplary embodiment, the biomarker is tumor RNA. In an exemplary embodiment, the biomarker is a messenger RNA (mRNA). In an exemplary embodiment, the responder phenotype has a decreased level of the biomarker compared to a non-responder phenotype. In an exemplary embodiment, the responder phenotype has an increased level of the biomarker compared to a non-responder phenotype. [0136] In an exemplary embodiment, the biomarker is selected from ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL- 8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL-10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ARG2, IL33, NEIL1, ICAM-1, IL-18, or a combination thereof. In an exemplary embodiment, the biomarker is selected from ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD 163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL- 10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ICAM-1, IL- 18, or a combination thereof. In an exemplary embodiment, the biomarker is selected from ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD 163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL- 10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ICAM-1, IL- 18, or a combination thereof, and the responder phenotype has a decreased level of the biomarker compared to a non-responder phenotype. In an exemplary embodiment, the biomarker is selected from ARG2, IL33, NEIL1, or a combination thereof. In an exemplary embodiment, the biomarker is selected from ARG2, IL33, NEIL1, or a combination thereof, and the responder phenotype has an increased level of the biomarker compared to a non-responder phenotype. [0137] In an exemplary embodiment, the biomarker is CXCL3 (MIP2P), CXCL8 (IL-8), or a combination thereof. In an exemplary embodiment, the biomarker is CXCL3 (MIP2P). In an exemplary embodiment, the biomarker is CXCL8 (IL-8). In an exemplary embodiment, the biomarker is a combination of CXCL3 (MIP2P) and CXCL8 (IL-8). In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 23 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 22 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 21 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 20 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 19 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 18 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 17 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 16 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 15 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 14 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 13 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 12 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 11 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a serum IL-8 level of 10 pg/ml or less. [0138] In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a plasma IL-8 level of 15 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a plasma IL-8 level of 14 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a plasma IL-8 level of 13 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a plasma IL-8 level of 12 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a plasma IL-8 level of 11 pg/ml or less. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a plasma IL-8 level of 10 pg/ml or less.

[0139] In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 40 normalized counts using Nanostring nCounter. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 35 normalized counts using Nanostring nCounter. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 30 normalized counts using Nanostring nCounter. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 35 normalized counts using Nanostring nCounter. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 20 normalized counts using Nanostring nCounter. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 15 normalized counts using Nanostring nCounter. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 10 normalized counts using Nanostring nCounter. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 8 TPM (transcripts per million) when using RNA sequencing. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 7 TPM (transcripts per million) when using RNA sequencing. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 6 TPM (transcripts per million) when using RNA sequencing. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 5 TPM (transcripts per million) when using RNA sequencing. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 4 TPM (transcripts per million) when using RNA sequencing. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 3 TPM (transcripts per million) when using RNA sequencing. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 2 TPM (transcripts per million) when using RNA sequencing. In an exemplary embodiment, the biomarker is CXCL8 (IL-8), and the responder phenotype has a tumor CXCL8 level of less than or equal to 1 TPM (transcripts per million) when using RNA sequencing.

[0140] In an exemplary embodiment, the biomarker is selected from an mRNA encoding ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD 163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL- 10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ARG2, IL33, NEIL1, ICAM-

1, IL- 18, or a combination thereof. In an exemplary embodiment, the biomarker is selected from an mRNA encoding ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20,

CCND2, CD163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL-10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ICAM-1, IL- 18, or a combination thereof. In an exemplary embodiment, the biomarker is selected from an mRNA encoding ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL-10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ICAM-1, IL- 18, or a combination thereof, and the responder phenotype has a decreased level of the biomarker compared to a non-responder phenotype. In an exemplary embodiment, the biomarker is selected from an mRNA encoding ARG2, IL33, NEIL1, or a combination thereof. In an exemplary embodiment, the biomarker is selected from an mRNA encoding ARG2, IL33, NEIL1, or a combination thereof, and the responder phenotype has an increased level of the biomarker compared to a non-responder phenotype.

[0141] In an exemplary embodiment, the biomarker is an mRNA encoding CXCL3 (MIP2P), CXCL8 (IL-8), or a combination thereof. In an exemplary embodiment, the biomarker is an mRNA encoding CXCL3 (MIP2P). In an exemplary embodiment, the biomarker is an mRNA encoding CXCL8 (IL-8). In an exemplary embodiment, the biomarker is a combination of an mRNA encoding CXCL3 (MIP2P) and an mRNA encoding CXCL8 (IL-8). Treatment modalities

[0142] In the methods of the invention, therapy is used to provide a positive therapeutic response with respect to a disease or condition. By “positive therapeutic response” is intended an improvement in the disease or condition, and/or an improvement in the symptoms associated with the disease or condition. For example, a positive therapeutic response would refer to one or more of the following improvements in the disease: (1) a reduction in the number of neoplastic cells; (2) an increase in neoplastic cell death; (3) inhibition of neoplastic cell survival; (5) inhibition (i.e., slowing to some extent, preferably halting) of tumor growth; (6) an increased human subject survival rate; and (7) some relief from one or more symptoms associated with the disease or condition.

[0143] Positive therapeutic responses in any given disease or condition can be determined by standardized response criteria specific to that disease or condition. Tumor response can be assessed for changes in tumor morphology (i.e., overall tumor burden, tumor size, and the like) using screening techniques such as magnetic resonance imaging (MRI) scan, x- radiographic imaging, computed tomographic (CT) scan, bone scan imaging, endoscopy, and tumor biopsy sampling and counting of tumor cells in the circulation.

[0144] In addition to these positive therapeutic responses, the subject undergoing therapy may experience the beneficial effect of an improvement in the symptoms associated with the disease.

[0145] Treatment according to the present invention includes a “therapeutically effective amount” of the medicaments used. A “therapeutically effective amount” refers to an amount effective, at dosages and for periods of time necessary, to achieve a desired therapeutic result.

[0146] A therapeutically effective amount may vary according to factors such as the disease state, age, sex, and weight of the individual, and the ability of the medicaments to elicit a desired response in the individual. A therapeutically effective amount is also one in which any toxic or detrimental effects of the antibody or antibody portion are outweighed by the therapeutically beneficial effects.

[0147] A “therapeutically effective amount” for tumor therapy may also be measured by its ability to stabilize the progression of disease. The ability of a compound to inhibit cancer may be evaluated in an animal model system predictive of efficacy in human tumors.

[0148] Alternatively, this property of a composition may be evaluated by examining the ability of the compound to inhibit cell growth or to induce apoptosis by in vitro assays known to the skilled practitioner. A therapeutically effective amount of a therapeutic compound may decrease tumor size, or otherwise ameliorate symptoms in a subject. One of ordinary skill in the art would be able to determine such amounts based on such factors as the subject’s size, the severity of the subject’s symptoms, and the particular composition or route of administration selected.

[0149] Dosage regimens are adjusted to provide the optimum desired response (e.g., a therapeutic response). For example, a single bolus may be administered, several divided doses may be administered over time or the dose may be proportionally reduced or increased as indicated by the exigencies of the therapeutic situation. Parenteral compositions may be formulated 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.

[0150] The specification for the dosage unit forms of the present invention are dictated by and directly dependent on (a) the unique characteristics of the active compound and the particular therapeutic effect to be achieved, and (b) the limitations inherent in the art of compounding such an active compound for the treatment of sensitivity in individuals.

[0151] The efficient dosages and the dosage regimens for XmAb717 depend on the disease or condition to be treated and may be determined by the persons skilled in the art.

[0152] In an exemplary embodiment, treatment with XmAb717 of subjects having a biomarker as disclosed herein achieves a clinical benefit selected from overall response rate, progression-free survival, overall survival, or a combination thereof. In an exemplary embodiment, treatment with XmAb717 achieves an overall response rate of at least about 30%, such as at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at about least 65%, at least about 70%, at least about 75%, or at least about 80%. In an exemplary embodiment, treatment with XmAb717 achieves progression-free survival three months after the initial administration of XmAb717 of at least about 30%, such as at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at about least 65%, at least about 70%, at least about 75%, or at least about 80%. In an exemplary embodiment, treatment with XmAb717 achieves progression-free survival six months after the initial administration of XmAb717 of at least about 30%, such as at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at about least 65%, at least about 70%, at least about 75%, or at least about 80%. In an exemplary embodiment, treatment with XmAb717 achieves progression-free survival twelve months after the initial administration of XmAb717 of at least about 30%, such as at least about 35%, at least about 40%, at least about 45%, at least about 50%, at least about 55%, at least about 60%, at about least 65%, at least about 70%, at least about 75%, or at least about 80%. In an exemplary embodiment, treatment with XmAb717 achieves an overall survival of at least about 8 months after the initial administration of XmAb717, such as at least about 9 months, as at least about 10 months, as at least about 11 months, at least about 12 months, at least about 13 months, at least about 14 months, at least about 15 months, at least about 16 months, at least about 17 months, at least about 18 months, at least about 19 months, at least about 20 months, at least about 21 months, at least about 22 months, at least about 23 months, at least about 2 years, at least about 3 years, at least about 4 years, or at least about 5 years.

[0153] In an exemplary embodiment, treatment with XmAb717 induces intratumoral T- cell inflammatory responses. In an exemplary embodiment, treatment with XmAb717 induces differential expression of an mRNA encoding C1QA, Cl QB, CD 163, CD38, CD3D, CD3E, CD5, CD8A, CD8B, CXCR6, CXCL9, CXCL10, CXCL11, FASLG, GBP1, GBP2, GBP4, GIMAP4, GZMA, GZMB, GZMH, GZMK, GZMM, ICOS, IFNG, IL18, IRF1, LAG3, MICB, NKG7, NOD2, PDCD1, PSMB9, STAT1, TAPI, TBX21, TIGIT, TLR8, ACVR1C, ARNT2, DTX4, C5AR1, CDKN2B, CXCL8 (IL-8), FAM124B, FGF18, GPC4, ILIA, TNFSF4, TTC30A, or a combination thereof. In an exemplary embodiment, treatment with XmAb717 induces increased expression of an mRNA encoding C1QA, Cl QB, CD 163, CD38, CD3D, CD3E, CD5, CD8A, CD8B, CXCR6, CXCL9, CXCL10, CXCL11, FASLG, GBP1, GBP2, GBP4, GIMAP4, GZMA, GZMB, GZMH, GZMK, GZMM, ICOS, IFNG, IL18, IRF1, LAG3, MICB, NKG7, NOD2, PDCD1, PSMB9, STAT1, TAPI, TBX21, TIGIT, TLR8, or a combination thereof. In an exemplary embodiment, treatment with XmAb717 decreases expression of an mRNA encoding ACVR1C, ARNT2, DTX4, C5AR1, CDKN2B, CXCL8 (IL-8), FAM124B, FGF18, GPC4, ILIA, TNFSF4, TTC30A, or a combination thereof. In an exemplary embodiment, the differential, increased, and/or decreased expression of an mRNA is measured in a serum sample. In an exemplary embodiment, the differential, increased, and/or decreased expression of an mRNA is measured in a plasma sample. In an exemplary embodiment, the differential, increased, and/or decreased expression of an mRNA is measured in a tumor sample. In an exemplary embodiment, treatment with XmAb717 induces expression of an mRNA encoding a gene product associated with increased PD-1, increased TH1 cells, increased CD8 T cells, increased cytotoxicity, increased lymphoid cells, increased T cells, increased NK CD56dim cells, increased TIGIT, decreased myeloid inflammation, or a combination thereof. In an exemplary embodiment, treatment with XmAb717 induces expression of an mRNA encoding a gene product associated with increased T cells (e.g., CD3D and/or CD8A), increased T-cell activation markers (e.g., GZMB, PDCD1, and/or ICOS), increased IFNy response/ Ag presentation (e.g., STAT1, TAPI, CXCL9, and/or IFNG), and decreases expression of an mRNA encoding a gene product associated with decreased myeloid inflammation (e.g., CXCL8 (IL-8) and/or C5AR1).

[0154] In an exemplary embodiment, treatment with XmAb717 induces differential expression of C1QA, C1QB, CD163, CD38, CD3D, CD3E, CD5, CD8A, CD8B, CXCR6, CXCL9, CXCL10, CXCL11, FASLG, GBP1, GBP2, GBP4, GIMAP4, GZMA, GZMB, GZMH, GZMK, GZMM, ICOS, IFNG, IL18, IRF1, LAG3, MICB, NKG7, N0D2, PDCD1, PSMB9, STAT1, TAPI, TBX21, TIGIT, TLR8, ACVR1C, ARNT2, DTX4, C5AR1, CDKN2B, CXCL8 (IL-8), FAM124B, FGF18, GPC4, ILIA, TNFSF4, TTC30A, or a combination thereof. In an exemplary embodiment, treatment with XmAb717 induces increased expression of C1QA, C1QB, CD163, CD38, CD3D, CD3E, CD5, CD8A, CD8B, CXCR6, CXCL9, CXCL10, CXCL11, FASLG, GBP1, GBP2, GBP4, GIMAP4, GZMA, GZMB, GZMH, GZMK, GZMM, ICOS, IFNG, IL18, IRF1, LAG3, MICB, NKG7, NOD2, PDCD1, PSMB9, STAT1, TAPI, TBX21, TIGIT, TLR8, or a combination thereof. In an exemplary embodiment, treatment with XmAb717 decreases expression of ACVR1C, ARNT2, DTX4, C5AR1, CDKN2B, CXCL8 (IL-8), FAM124B, FGF18, GPC4, ILIA, TNFSF4, TTC30A, or a combination thereof. In an exemplary embodiment, the differential, increased, and/or decreased expression is measured in a serum sample. In an exemplary embodiment, the differential, increased, and/or decreased expression is measured in a plasma sample. In an exemplary embodiment, the differential, increased, and/or decreased expression is measured in a tumor sample. In an exemplary embodiment, treatment with XmAb717 induces expression of a gene product associated with increased PD-1, increased TH1 cells, increased CD8 T cells, increased cytotoxicity, increased lymphoid cells, increased T cells, increased NK CD56dim cells, increased TIGIT, decreased myeloid inflammation, or a combination thereof. In an exemplary embodiment, treatment with XmAb717 induces expression of a gene product associated with increased T cells (e.g., CD3D and/or CD8A), increased T-cell activation markers (e.g., GZMB, PDCD1, and/or ICOS), increased fFNy response/ Ag presentation (e.g., STAT1, TAPI, CXCL9, and/or IFNG), and decreases expression of a gene product associated with decreased myeloid inflammation (e.g., CXCL8 (IL-8) and/or C5AR1).

[0155] In an exemplary embodiment, treatment with XmAb717 induces increased cellular immunity (e.g., increased CD8+ T cells), induction of MHC I antigen presenting machinery (B2M), increased IFN pathway response (e.g., upregulation of PD-L1), or a combination thereof.

[0156] In an exemplary embodiment, if the subject does not have the responder phenotype as disclosed herein (i.e., the subject has a non-responder phenotype), the subject is administered an alternative treatment that is not the bispecific antibody comprising a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3 as disclosed herein. In an exemplary embodiment, the alternative treatment is an anti -PD-1 therapy, an anti-PDLl therapy, an anti-CTLA4 therapy, or a combination thereof. In an exemplary embodiment, the alternative treatment is pembrolizumab, nivolumab, atelizumab, avelumab, ipilimumab, or a combination thereof.

[0157] All cited references are herein expressly incorporated by reference in their entirety.

[0158] Whereas particular embodiments of the invention have been described above for purposes of illustration, it will be appreciated by those skilled in the art that numerous variations of the details may be made without departing from the invention as described in the appended claims.

EXAMPLES

[0159] Examples are provided below to illustrate the present invention. These examples are not meant to constrain the present invention to any particular application or theory of operation. For all constant region positions discussed in the present invention, numbering is according to the EU index as in Kabat (Kabat et al., 1991, Sequences of Proteins of Immunological Interest, 5th Ed., United States Public Health Service, National Institutes of Health, Bethesda, entirely incorporated by reference). Those skilled in the art of antibodies will appreciate that this convention consists of nonsequential numbering in specific regions of an immunoglobulin sequence, enabling a normalized reference to conserved positions in immunoglobulin families. Accordingly, the positions of any given immunoglobulin as defined by the EU index will not necessarily correspond to its sequential sequence.

[0160] General and specific scientific techniques are outlined in US Publications 2015/0307629, and 2014/0288275, as well as PCT Publication WO2014/145806, as well as

US Applications 62/085,027, 14/952,714, and 15/141,350, all of which are expressly incorporated by reference in their entirety and particularly for the techniques outlined therein. EXAMPLE 1

XmAb717 Treatment Overview

[0161] XmAb717 (vudalimab) (SEQ ID NOs: 1-3; depicted in FIG. 2) is a humanized bispecific monoclonal antibody that simultaneously targets PD-1 and CTLA-4 and binds preferentially to PD-l/CTLA-4 dual-positive cells. DUET-2 (XmAb20717-01) is an ongoing, Phase 1, first-in-human, multicenter, dose-escalation and -expansion study in patients with selected advanced solid tumors including melanoma, non-small cell lung cancer (NSCLC), renal cell carcinoma (RCC), castration-resistant prostate cancer (CRPC), and others (e.g., ovarian and cervical cancers). 10 mg/kg XmAb717 every 2 weeks (Q2W) was selected for tumor-specific expansion cohorts based on consistent T-cell proliferation in peripheral blood indicative of dual PD-l/CTLA-4 checkpoint blockade and response to treatment per RECIST 1.1. The primary objectives was to determine the safety and tolerability profile and the maximum tolerated dose (MTD) or recommended dose of XmAb717 for further evaluation. The secondary objectives were to characterize the PK and immunogenicity of XmAb717; and to assess antitumor activity, based on objective response and best overall response rates (RECIST 1.1), duration of response, and progression-free survival. FIG. 3 shows a waterfall plot of all patients. Key exploratory objectives include characterizing the pharmacodynamics of XmAb717, based on post-dosing changes in immune activity in peripheral blood and tumor; and evaluating the correlation between response to treatment and tumor mutational burden and gene expression signatures. These assessments included a serum proinflammatory cytokine panel and an assessment of baseline tumor biopsy using Nanostring mRNA 10360.

Serum Cytokine Assessment

[0162] Serum from patients dosed at > 10 mg/kg XmAb717 was assessed at baseline for cytokine levels using the human MAP immunoassay platform (Myriad RBM, Austin, TX, USA). High or low expression of certain cytokines were correlated with clinical benefit. It was found that IL-8 is a strong predictor of response. As depicted in FIG. 4A-4C, baseline serum levels of IL-8, IL- 10, and IL-6 trended lower in patients who achieved CR/PR (complete responders/partial responders) on study. Based on the analysis, 23 pg/ml was identified as a median cut-off for IL-8 (i.e., IL8 < 23 pg/ml is biomarker positive and IL8 > 23 pg/ml is biomarker negative). The data indicate that lower baseline serum levels of immunosuppressive factors are associated with XmAb717 clinical response. Elevated IL-8, IL-6 and IL-10 have previously been associated with myeloid-derived suppressor cells and for IL-8, diminished responses to checkpoint blockade.

Tumor Cytokine Assessment

[0163] Baseline gene expression in tumor samples from CR/PR vs SD/PD (stable disease/progressive disease) patients was evaluated from the 10360 panel (data depicted in FIG. 6; IL-8 (CXCL8) and CXCL3 are further depicted in FIG. 7A-7B). The data show that low IL8 and CXCL3 was associated with clinical benefit. Increases in intratumoral IL-8 and CXCL3 are recruitment factors for inhibitory myeloid-derived cells (TAM, MDSCs, neutrophils) and are associated with diminished checkpoint response.

XmAb71 7 Induces Peripheral T Cell Activation and Proliferation

[0164] Peripheral flow cytometry demonstrated dual CTLA4/PD1 blockade pharmacodynamic activity, peaking at C2D1 (cycle 2, day 1). Proliferation (%Ki-67) was robustly observed in both CD4+ and CD8+ T cells (data depicted in FIG. 8A, where values represent the absolute change in the frequency (%) of ki67+ T cells from baseline). ICOS upregulation was also observed on both CD4+ and CD8+ T cells (data depicted in FIG. 8B, where values represent the absolute change in the frequency (%) of ICOS+ T cells from baseline). [0165] XmAb717 Induces Intratumoral T Cell Inflammatory Responses mRNA profiling of FFPE tumor biopsies was performed using the nCounter® PanCancer IO 360™ Panel. 10360 individual genes and 10360 gene scores were analyzed in 23 paired biopsies (data depicted in FIG. 9A and FIG. 9B, respectively). XmAb717 PD effects included induction of genes associated with increased T cells (CD3D, CD8A), T cell activation markers (GZMB, PDCD1, ICOS), increased IFNg response/ Ag presentation (STAT1, TAPI, CXCL9, IFNG) and decreased myeloid inflammation (10360 gene score and CXCL8, C5aR).

IL-8 as a predictor of clinical response to XmAb717

[0166] Progression-free survival (PFS), time on treatment (ToT), and overall survival (OS) was associated with IL-8 concentration in serum of patients treated with XmAb717 (FIG. 5A-5C). For example, patients having less than 23 pg/ml IL-8 in their serum demonstrated improved PFS, ToT, and OS as compared to patients having more than 23 pg/ml IL-8 in their serum.

[0167] Indeed, there was an observed association with CXCL8 (IL-8) biomarker levels and overall survival (OS) in blood in melanoma, non-small cell lung carcinoma (NSCLC) and CRPC patients (FIG. 10A-10C). For example, IL-8 biomarker positive patients having castrate resistant adenocarcinoma, non-small cell lung carcinoma (NSCLC) patient cohort, ovarian or fallopian tube carcinoma and renal cell carcinoma (clear cell predominant type) demonstrated an increased response rate to treatment with XmAb717. In contrast, IL-8 negative melanoma patients exhibited a higher response rate (FIG. 11). Surprisingly, baseline serum levels of IL-8 trended lower in patients who achieved CR/PR (complete responders/partial responders) (FIG. 12). There was also an observed strong survival probability association of low baseline IL-8 and PFS, Time on Treatment, and OS (FIG.

13A-13C). [0168] Specific embodiments disclosed herein can be further limited in the claims using

“consisting of’ or “consisting essentially of’ language. When used in the claims, whether as filed or added per amendment, the transition term “consisting of’ excludes any element, step, or ingredient not specified in the claims. The transition term “consisting essentially of’ limits the scope of a claim to the specified materials or steps and those that do not materially affect the basic and novel characteristic(s). Embodiments of the disclosure so claimed are inherently or expressly described and enabled herein.

[0169] In cases where numerical values are indicated in the context of the present disclosure, the skilled person will understand that the technical effect of the feature in question is ensured within an interval of accuracy, which typically encompasses a deviation of the numerical value given of ± 10%, and preferably of ± 5%. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0170] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight and median size, reaction conditions, and so forth used in the specification and claims are to be understood as being modified in all instances by the term “about.” Accordingly, unless indicated to the contrary, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present disclosure.

[0171] The terms “a,” “an,” “the” and similar referents used in the context of describing the disclosure (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. Recitation of ranges of values herein is merely intended to serve as a shorthand method of referring individually to each separate value falling within the range. Unless otherwise indicated herein, each individual value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples or exemplary language (e.g., “such as”) provided herein is intended merely to better illuminate the disclosure and does not pose a limitation on the scope of the disclosure otherwise claimed. No language in the specification should be construed as indicating any non-claimed element essential to the practice of the disclosure.

[0172] Groupings of alternative elements or embodiments of the disclosure disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. It is anticipated that one or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is deemed to contain the group as modified, thus fulfilling the written description of all Markush groups used in the appended claims.

[0173] Certain embodiments of this disclosure are described herein, including the best mode known to the inventor for carrying out the disclosure. Of course, variations on these described embodiments will become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventor expects skilled artisans to employ such variations as appropriate, and the inventor intends for the disclosure to be practiced other than as specifically described herein. Accordingly, this disclosure includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the disclosure unless otherwise indicated herein or otherwise clearly contradicted by context.

[0174] It is to be understood that the embodiments of the disclosure disclosed herein are illustrative of the principles of the present disclosure. Other modifications that can be employed are within the scope of the disclosure. Thus, by way of example, but not of limitation, alternative configurations of the present disclosure can be utilized in accordance with the teachings herein. Accordingly, the present disclosure is not limited to that precisely as shown and described.

[0175] While the present disclosure has been described and illustrated herein by references to various specific materials, procedures and examples, it is understood that the disclosure is not restricted to the particular combinations of materials and procedures selected for that purpose. Numerous variations of such details can be implied as will be appreciated by those skilled in the art. It is intended that the specification and examples be considered as exemplary only, with the true scope and spirit of the disclosure being indicated by the following claims. All references, patents, and patent applications referred to in this application are herein incorporated by reference in their entirety.

Claims

What is claimed is:

1. A method for treating a solid cancerous tumor in a human subject, comprising:

(a) measuring a biomarker level in a sample from the human subject having the solid cancerous tumor to identify the subject as having a responder phenotype; and

(b) administering a bispecific antibody to the subject having the responder phenotype; wherein the bispecific antibody comprises a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3.

2. A method for treating a solid cancerous tumor in a human subject, comprising: administering a bispecific antibody to the subject; wherein the bispecific antibody comprises a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3; and wherein a sample from the subject has a biomarker level that identifies the subject as a responder phenotype to the bispecific antibody.

3. A method for selecting a subject for treatment with a bispecific antibody that comprises a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3, the method comprising: measuring a biomarker level in a sample from the human subject having the solid cancerous tumor to identify the subject as having a responder phenotype.

4. The method of any one of claims 1 to 3, wherein the sample is selected from a serum sample, a plasma sample, or a tumor sample.

5. The method of any one of the preceding claims, wherein the biomarker is selected from ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL-10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ARG2, IL33, NEIL1, ICAM-1, IL- 18, or a combination thereof.

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6. The method of any one of claims 1 to 4, wherein the responder phenotype has a decreased level of the biomarker compared to a non-responder phenotype.

7. The method of claim 6, wherein the biomarker is selected from ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL-10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ICAM-1, IL- 18, or a combination thereof.

8. The method of any one of claims 1 to 4, wherein the responder phenotype has an increased level of the biomarker compared to a non-responder phenotype.

9. The method of claim 8, wherein the biomarker is selected from ARG2, IL33, NEIL1, or a combination thereof.

10. The method of any one of claims 1 to 7, wherein the biomarker is IL-8.

11. The method of any one of claims 1 to 7, wherein the biomarker is IL-8 and the responder phenotype has a serum IL-8 level of 23 pg/ml or less.

12. The method of any one of claims 1 to 7, wherein the biomarker is IL-8 and the responder phenotype has a plasma IL-8 level of 15 pg/ml or less.

13. The method of any one of claims 1 to 7, wherein the biomarker is IL-8 and the responder phenotype has a tumor CXCL8 level of less than or equal to 40 normalized counts using Nanostring nCounter, or less than or equal to 8 TPM (transcripts per million) when using RNA sequencing.

14. The method of any one of claims 1 or 4 to 7, wherein if the subject does not have the responder phenotype, the subject is administered an alternative treatment that is not the bispecific antibody comprising a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID NO: 3.

15. The method of any one of the preceding claims, wherein the solid cancerous tumor is selected from melanoma, cervical cancer, breast cancer, hepatocellular cancer,

60 urothelial cancer, bladder cancer, head and neck cancer, renal cell cancer, colorectal cancer, endometrial cancer, small cell lung cancer, non-small cell lung cancer, gastric cancer, gastroesophageal junction cancer, mesothelioma, neuroendocrine cancer, anal cancer, prostate cancer, nasopharyngeal cancer, cholangiocarcinoma, malignant adnexal tumor chondrosarcoma, Leydig tumor, parotid adenocarcinoma, ovarian cancer, or fallopian tube cancer.

16. The method of any one of the preceding claims, wherein the solid cancerous tumor is selected from prostate cancer, ovarian cancer, endometrial cancer, or cervical cancer.

17. The method of any one of the preceding claims, wherein the bispecific antibody is administered intravenously.

18. The method of any one of the preceding claims, wherein the bispecific antibody is administered once every 13-15 days in a dose of between about 0.05 mg/kg and about 12 mg/kg.

19. The method of any one of the preceding claims, wherein the bispecific antibody is administered once every two weeks in a dose of about 10 mg/kg.

20. The method of any one of the preceding claims, wherein the bispecific antibody is administered for about 3 weeks to about 9 weeks.

21. The method of any one of the preceding claims, wherein the subject previously received anti-PD-1 therapy, anti-PDLl therapy, and/or anti-CTLA4 therapy.

22. The method of any one of the preceding claims, wherein the subject is relapsed and/or refractory to an anti-PD-1 therapy, an anti-PDLl therapy, and/or an anti- CTLA4 therapy.

23. The method of any one of the preceding claims, wherein the treatment achieves a clinical benefit selected from overall response rate, progression-free survival, overall survival, or a combination thereof.

24. A bispecific antibody product comprising: a) a bispecific antibody that comprises a first monomer comprising SEQ ID NO: 1, a second monomer comprising SEQ ID NO: 2, and a light chain comprising SEQ ID

61 NO: 3; and b) a label providing that the bispecific antibody is indicated for use in a human subject having a responder phenotype, wherein the responder phenotype is identified by a biomarker level in a sample from the subject.

25. The product of claim 24, wherein the sample is selected from a serum sample, a plasma sample, or a tumor sample.

26. The product of claim 24 or 25, wherein the biomarker is selected from ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD 163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL- 10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ARG2, IL33, NEIL1, ICAM- 1, IL- 18, or a combination thereof.

27. The product of claim 24 or 25, wherein the responder phenotype has a decreased level of the biomarker compared to a non-responder phenotype.

28. The product of claim 27, wherein the biomarker is selected from ACVR1C, ANLN, BCL2, BRIP1, CASP1, CCL4, CCL20, CCND2, CD163, CDH2, CDKN1C, CDKN2A, CLEC5A, CLEC7A, CNTFR, COL17A1, CXCL1, CXCL2, CXCL3 (MIP2p), CXCL8 (IL-8), CXCL9, CXCL12, CXCR2, FANCA, FCAR, FZD9, IL-6, IL-10, IL-15, ITGB8, KIT, LILRA3, MAPK10, NECTIN1, PLA2G2A, PROMI, S100A12, SFRP1, SHC2, TLR5, TNFRSF10B, TNKS, WNT2, WNT7B, XCL1/2, ICAM-1, IL- 18, or a combination thereof.

29. The product of claim 24 or 25, wherein the responder phenotype has an increased level of the biomarker compared to a non-responder phenotype.

30. The product of claim 29, wherein the biomarker is selected from ARG2, IL33, NEIL1, or a combination thereof.

31. The product of any one of claims 24 to 28, wherein the biomarker is IL-8.

32. The product of any one of claims 24 to 28, wherein the biomarker is IL-8 and the responder phenotype has a serum IL-8 level of 23 pg/ml or less.

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33. The product of any one of claims 24 to 28, wherein the biomarker is IL-8 and the responder phenotype has a plasma IL-8 level of 15 pg/ml or less.

34. The product of any one of claims 24 to 28, wherein the biomarker is IL-8 and the responder phenotype has a tumor CXCL8 level of less than or equal to 40 normalized counts using Nanostring nCounter, or less than or equal to 8 TPM (transcripts per million) when using RNA sequencing.

35. The product of any one of claims 24 to 34, wherein the solid cancerous tumor is selected from melanoma, cervical cancer, breast cancer, hepatocellular cancer, urothelial cancer, bladder cancer, head and neck cancer, renal cell cancer, colorectal cancer, endometrial cancer, small cell lung cancer, non-small cell lung cancer, gastric cancer, gastroesophageal junction cancer, mesothelioma, neuroendocrine cancer, anal cancer, prostate cancer, nasopharyngeal cancer, cholangiocarcinoma, malignant adnexal tumor chondrosarcoma, Leydig tumor, parotid adenocarcinoma, ovarian cancer, or fallopian tube cancer.

36. The product of any one of claims 24 to 35, wherein the solid cancerous tumor is selected from prostate cancer, ovarian cancer, endometrial cancer, or cervical cancer.

37. The product of any one of claims 24 to 36, wherein the bispecific antibody is administered intravenously.

38. The product of any one of claims 24 to 37, wherein the bispecific antibody is administered once every 13-15 days in a dose of between about 0.05 mg/kg and about 12 mg/kg.

39. The product of any one of claims 24 to 38, wherein the bispecific antibody is administered once every two weeks in a dose of about 10 mg/kg.

40. The product of any one of claims 24 to 39, wherein the bispecific antibody is administered for about 3 weeks to about 9 weeks.

41. The product of any one of claims 24 to 40, wherein the subject previously received anti-PD-1 therapy, anti-PDLl therapy, and/or anti-CTLA4 therapy.

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42. The product of any one of claims 24 to 41, wherein the subject is relapsed and/or refractory to an anti-PD-1 therapy, an anti-PDLl therapy, and/or an anti-CTLA4 therapy.

43. The product of any one of claims 24 to 42, wherein the treatment achieves a clinical benefit selected from overall response rate, progression-free survival, overall survival, or a combination thereof.