WO2017106609A2 - Pdgfr beta antibody - Google Patents

Abstract

Provided herein are antibody agents that bind to PDGFRβ. Provided herein are also isolated nucleic acids encoding antibody agents that bind to PDGFRβ, nucleic acid vectors and prokaryotic or eukaryotic host cells including such isolated nucleic acids, as well as compositions including and methods of using such antibody agents.

Description

PDGFR BETA ANTIBODY

CROSS REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of priority to U.S. Application No. 62/268,424, filed December 16, 2015, which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

[0002] The invention relates to antibodies that bind to PDGFR . The antibodies are used for treating neoplastic disease, hyperproliferative, differentiation and developmental disorders, and can be used alone or in combination with other agents.

BACKGROUND OF THE INVENTION

[0003] Platelet derived growth factor (PDGF) has a variety of known biological functions, including in cell proliferation and differentiation, and plays a significant role in blood vessel formation. The biological target of PDGF is platelet derived growth factor receptor (PDGFR), a dimeric transmembrane tyrosine kinase. Dimeric PDGFR consists of two a or two β subunits, or one of each. PDGFR has important functions in cell proliferation, cellular differentiation, cell growth, development and many diseases including cancer.

[0004] A number of different therapeutic antibodies have been developed and marketed that target the interaction between certain growth factors and their natural receptors. No therapeutic antibody has been approved so far that specifically targets PDGF signaling by binding to PDGFR . Thus, there is a need for novel therapeutic antibodies that target PDGFR . BRIEF DESCRIPTION OF THE DRAWING

[0005] FIG. 1 illustrates the overall strategy that was used to isolate the antibodies of the invention.

[0006] FIG. 2 shows the amino acid sequences of the heavy and light chain variable regions of human antibodies PFH2 and PFF9. Kabat CDRs are boxed, and Chothia CDRs are highlighted.

[0007] FIG. 3 illustrates the binding of antibodies PFH2 and PFF9 to soluble (A) human, (B) murine and (C) rat PDGFRP, as well as to (D) PDGFR expressed by Human Embryonic Kidney 293 cells. By contrast, the control anti- PDGFR antibody does not bind to PDGFR from mouse rat.

[0008] FIG. 4 illustrates (A) the binding of antibodies PFH2 and PFF9 to the ligand binding domain (domains 1-3) of human PDGFRP , and (B) the blocking of PDGFbb to PDGFRp by antibodies PFH2 and PFF9.

[0009] FIG. 5 illustrates the inhibition of phosphorylation of PDGFRP and downstream signaling molecule MAPK by antibody PFH2.

[0010] FIG. 6 provides a summary of the characteristics of human antibodies PFH2 and PFF9.

[0011] FIG. 7 shows the structure and amino acid sequences of the bi-specific anti- VEGFR2/anti- PDGFRP antibody BlAlIgG-scFvH2.

DETAILED DESCRIPTION OF THE INVENTION

Definitions

[0012] In order for the present invention to be more readily understood, certain terms are first defined below. Additional definitions for the following terms and other terms are set forth throughout the specification. [0013] Administering: As used herein, the term "administering" means delivering antibody agents, other proteins, or small molecules set forth herein to a subject by any method that may achieve the result sought. They may be administered, for example, subcutaneously, intravenously or intramuscularly.

[0014] Amino acid: As used herein, the term "amino acid," in its broadest sense, refers to any compound and/or substance that can be incorporated into a polypeptide chain. In some embodiments, an amino acid has the general structure H₂N-- C(H)(R)— COOH. In some embodiments, an amino acid is a naturally occurring amino acid. In some embodiments, an amino acid is a synthetic amino acid; in some embodiments, an amino acid is a D-amino acid; in some embodiments, an amino acid is an L-amino acid. "Standard amino acid" refers to any of the twenty standard L-amino acids commonly found in naturally occurring peptides. "Nonstandard amino acid" refers to any amino acid, other than the standard amino acids, regardless of whether it is prepared synthetically or obtained from a natural source. As used herein, "synthetic amino acid" encompasses chemically modified amino acids, including but not limited to salts, amino acid derivatives (such as amides), and/or substitutions. Amino acids, including carboxy- and/or amino-terminal amino acids in peptides, can be modified by methylation, amidation, acetylation, protecting groups, and/or substitution with other chemical groups that can change the peptide's circulating half- life without adversely affecting their activity. Amino acids may comprise one or posttranslational modifications, such as association with one or more chemical entities (e.g., methyl groups, acetate groups, acetyl groups, phosphate groups, formyl moieties, isoprenoid groups, sulfate groups, polyethylene glycol moieties, lipid moieties, carbohydrate moieties, biotin moieties, etc.). The term "amino acid" is used interchangeably with "amino acid residue," and may refer to a free amino acid and/or to an amino acid residue of a peptide. It will be apparent from the context in which the term is used whether it refers to a free amino acid or a residue of a peptide.

[0015] Animal: As used herein, the term "animal" refers to any member of the animal kingdom. In some embodiments, "animal" refers to humans, of either sex and at any stage of development. In some embodiments, "animal" refers to non-human animals, at any stage of development. In certain embodiments, the non-human animal is a mammal (e.g., a rodent, a mouse, a rat, a rabbit, a monkey, a dog, a cat, a sheep, cattle, a primate, and/or a pig). In some embodiments, animals include, but are not limited to, mammals, birds, reptiles, amphibians, fish, insects, and/or worms. In certain embodiments, the animal is susceptible to infection by HCV. In some embodiments, an animal may be a transgenic animal, genetically engineered animal, and/or a clone.

[0016] Antibody: As used herein, the term "antibody" refers to a polypeptide that includes canonical immunoglobulin sequence elements sufficient to confer specific binding to a particular target antigen. As is known in the art, intact antibodies as produced in nature are approximately 150 kD tetrameric agents comprised of two identical heavy chain polypeptides (about 50 kD each) and two identical light chain polypeptides (about 25 kD each) that associate with each other into what is commonly referred to as a "Y-shaped" structure. Each heavy chain is comprised of at least four domains (each about 110 amino acids long) - an amino-terminal variable (VH) domain (located at the tips of the Y structure), followed by three constant domains: CHI, CH2, and the carboxy -terminal CH3 (located at the base of the Y's stem). A short region, known as the "switch", connects the heavy chain variable and constant regions. The "hinge" connects CH2 and CH3 domains to the rest of the antibody. Two disulfide bonds in this hinge region connect the two heavy chain polypeptides to one another in an intact antibody. Each light chain is comprised of two domains - an amino-terminal variable (VL) domain, followed by a carboxy -terminal constant (CL) domain, separated from one another by another "switch". Intact antibody tetramers are comprised of two heavy chain- light chain dimers in which the heavy and light chains are linked to one another by a single disulfide bond; two other disulfide bonds connect the heavy chain hinge regions to one another, so that the dimers are connected to one another and the tetramer is formed. Naturally -produced antibodies are also

glycosylated, typically on the CH2 domain. Each domain in a natural antibody has a structure characterized by an "immunoglobulin fold" formed from two beta sheets (e.g., 3-, 4-, or 5-stranded sheets) packed against each other in a compressed antiparallel beta barrel. Each variable domain contains three hypervariable loops known as

"complement determining regions" (CDR1 , CDR2, and CDR3) and four somewhat invariant "framework" regions (FR1, FR2, FR3, and FR4). When natural antibodies fold, the FR regions form the beta sheets that provide the structural framework for the domains, and the CDR loop regions from both the heavy and light chains are brought together in three-dimensional space so that they create a single hypervariable antigen binding site located at the tip of the Y structure. Amino acid sequence comparisons among antibody polypeptide chains have defined two light chain (κ and λ) classes, several heavy chain (e.g., μ, γ, α, ε, δ) classes, and certain heavy chain subclasses (al, a2, γΐ, γ2, γ3, and γ4). Antibody classes (IgA [including IgAl, IgA2], IgD, IgE, IgG [including IgGl, IgG2, IgG3, IgG4], IgM) are defined based on the class of the utilized heavy chain sequences. For purposes of the present invention, in certain embodiments, any polypeptide or complex of polypeptides that includes sufficient immunoglobulin domain sequences as found in natural antibodies can be referred to and/or used as an "antibody", whether such polypeptide is naturally produced (e.g., generated by an organism reacting to an antigen), or produced by recombinant engineering, chemical synthesis, or other artificial system or methodology. In some embodiments, an antibody is monoclonal; in some embodiments, an antibody is polyclonal. In some embodiments, an antibody has constant region sequences that are characteristic of mouse, rabbit, primate, or human antibodies. In some embodiments, an antibody sequence elements are humanized, primatized, chimeric, etc, as is known in the art. Moreover, the term "antibody" as used herein, will be understood to encompass (unless otherwise stated or clear from context) and can refer in appropriate embodiments to any of the art-known or developed constructs or formats for capturing antibody structural and functional features in alternative presentation. For example, in some embodiments, the term can refer to bi- or other multi- specific (e.g., zybodies, etc) antibodies, Small Modular Immuno Pharmaceuticals (SMIPs™ ), single chain antibodies, cameloid antibodies, and/or antibody fragments. In some embodiments, an antibody may lack a covalent modification (e.g., attachment of a glycan) that it would have if produced naturally. In some embodiments, an antibody may contain a covalent modification (e.g., attachment of a glycan, a payload [e.g., a detectable moiety, a therapeutic moiety, a catalytic moiety, etc], or other pendant group [e.g., poly-ethylene glycol, etc]).

[0017] Antibody agent: As used herein, the term "antibody agent" refers to an agent that specifically binds to a particular antigen. In some embodiments, the term encompasses any polypeptide with immunoglobulin structural elements sufficient to confer specific binding. Suitable antibody agents include, but are not limited to, human antibodies, primatized antibodies, chimeric antibodies, bi-specific antibodies, humanized antibodies, conjugated antibodies (i.e., antibodies conjugated or fused to other proteins, radiolabels, cytotoxins), Small Modular ImmunoPharmaceuticals (SMIPs™), single chain antibodies, cameloid antibodies, and antibody fragments. As used herein, the term "antibody agent" also includes intact monoclonal antibodies, polyclonal antibodies, single domain antibodies (e.g., shark single domain antibodies (e.g., IgNAR or fragments thereof)), multispecific antibodies (e.g. bi-specific antibodies) formed from at least two intact antibodies, and antibody fragments so long as they exhibit the desired biological activity. In some embodiments, the term encompasses stapled peptides. In some embodiments, the term encompasses one or more antibody- like binding peptidomimetics. In some embodiments, the term encompasses one or more antibody- like binding scaffold proteins. In come

embodiments, the term encompasses monobodies or adnectins. In many embodiments, an antibody agent is or comprises a polypeptide whose amino acid sequence includes one or more structural elements recognized by those skilled in the art as a

complementarity determining region (CDR); in some embodiments an antibody agent is or comprises a polypeptide whose amino acid sequence includes at least one CDR (e.g., at least one heavy chain CDR and/or at least one light chain CDR) that is substantially identical to one found in a reference antibody. In some embodiments an included CDR is substantially identical to a reference CDR in that it is either identical in sequence or contains between 1-5 amino acid substitutions as compared with the reference CDR. In some embodiments an included CDR is substantially identical to a reference CDR in that it shows at least 85%, 86%, 87%, 88%, 89%, 90%, 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity with the reference CDR. In some embodiments an included CDR is substantially identical to a reference CDR in that it shows at least 96%, 96%, 97%, 98%, 99%, or 100% sequence identity with the reference CDR. In some embodiments an included CDR is substantially identical to a reference CDR in that at least one amino acid within the included CDR is deleted, added, or substituted as compared with the reference CDR but the included CDR has an amino acid sequence that is otherwise identical with that of the reference CDR. In some embodiments an included CDR is substantially identical to a reference CDR in that 1-5 amino acids within the included CDR are deleted, added, or substituted as compared with the reference CDR but the included CDR has an amino acid sequence that is otherwise identical to the reference CDR . In some embodiments an included CDR is substantially identical to a reference CDR in that at least one amino acid within the included CDR is substituted as compared with the reference CDR but the included CDR has an amino acid sequence that is otherwise identical with that of the reference CDR. In some embodiments an included CDR is substantially identical to a reference CDR in that 1-5 amino acids within the included CDR are deleted, added, or substituted as compared with the reference CDR but the included CDR has an amino acid sequence that is otherwise identical to the reference CDR. In some embodiments, an antibody agent is or comprises a polypeptide whose amino acid sequence includes structural elements recognized by those skilled in the art as an immunoglobulin variable domain. In some embodiments, an antibody agent is a polypeptide protein having a binding domain which is homologous or largely homologous to an immunoglobulin-binding domain. The term antibody agent includes chimeric antigen receptors.

[0018] Antibody fragment: As used herein, an "antibody fragment" includes a portion of an intact antibody, such as, for example, the antigen-binding or variable region of an antibody. Examples of antibody fragments include Fab, Fab', F(ab')2, and Fv fragments; triabodies; tetrabodies; linear antibodies; single-chain antibody molecules; and multi specific antibodies formed from antibody fragments. For example, antibody fragments include isolated fragments, "Fv" fragments, consisting of the variable regions of the heavy and light chains, recombinant single chain polypeptide molecules in which light and heavy chain variable regions are connected by a peptide linker ("ScFv proteins"), and minimal recognition units consisting of the amino acid residues that mimic the hypervariable region. In many embodiments, an antibody fragment contains sufficient sequence of the parent antibody of which it is a fragment that it binds to the same antigen as does the parent antibody; in some embodiments, a fragment binds to the antigen with a comparable affinity to that of the parent antibody and/or competes with the parent antibody for binding to the antigen. Examples of antigen binding fragments of an antibody include, but are not limited to, Fab fragment, Fab' fragment, F(ab')2 fragment, scFv fragment, Fv fragment, dsFv diabody, dAb fragment, Fd' fragment, Fd fragment, and an isolated complementarity determining region (CDR) region. An antigen binding fragment of an antibody may be produced by any means. For example, an antigen binding fragment of an antibody may be enzymatically or chemically produced by fragmentation of an intact antibody and/or it may be recombinantly produced from a gene encoding the partial antibody sequence. Alternatively or additionally, antigen binding fragment of an antibody may be wholly or partially synthetically produced. An antigen binding fragment of an antibody may optionally comprise a single chain antibody fragment. Alternatively or additionally, an antigen binding fragment of an antibody may comprise multiple chains which are linked together, for example, by disulfide linkages. An antigen binding fragment of an antibody may optionally comprise a multimolecular complex. A functional antibody fragment typically comprises at least about 50 amino acids and more typically comprises at least about 200 amino acids.

[0019] Approximately: As used herein, the term "approximately" or "about," as applied to one or more values of interest, refers to a value that is similar to a stated reference value. In certain embodiments, the term "approximately" or "about" refers to a range of values that fall within 25%, 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1 %, or less in either direction (greater than or less than) of the stated reference value unless otherwise stated or otherwise evident from the context (except where such number would exceed 100% of a possible value).

[0020] Combination therapy: The term "combination therapy", as used herein, refers to those situations in which two or more different pharmaceutical agents are administered in overlapping regimens so that the subject is simultaneously exposed to both (or the plurality of) agents.

[0021] Dosage form: As used herein, the terms "dosage form" and "unit dosage form" refer to a physically discrete unit of a therapeutic protein (e.g., antibody) for the patient to be treated. Each unit contains a predetermined quantity of active material calculated to produce the desired therapeutic effect. It will be understood, however, that the total dosage of the composition will be decided by the attending physician within the scope of sound medical judgment. [0022] Dosing regimen: A "dosing regimen" (or "therapeutic regimen"), as that term is used herein, is a set of unit doses (typically more than one) that are administered individually to a subject, typically separated by periods of time. In some embodiments, a given therapeutic agent has a recommended dosing regimen, which may involve one or more doses. In some embodiments, a dosing regimen comprises a plurality of doses each of which are separated from one another by a time period of the same length; in some embodiments, a dosing regimen comprises a plurality of doses and at least two different time periods separating individual doses. In some embodiments, all doses within a dosing regimen are of the same unit dose amount. In some embodiments, different doses within a dosing regimen are of different amounts. In some

embodiments, a dosing regimen comprises a first dose in a first dose amount, followed by one or more additional doses in a second dose amount different from the first dose amount. In some embodiments, a dosing regimen comprises a first dose in a first dose amount, followed by one or more additional doses in a second dose amount same as the first dose amount.

[0023] Gene: As used herein, the term "gene" has its meaning as understood in the art. As used in the present application, the term "gene" generally refers to a portion of a nucleic acid that encodes a protein. However, the term "gene" may include gene regulatory sequences (e.g., promoters, enhancers, etc.) and/or intron sequences.

[0024] Homology: As used herein, the term "homology" refers to the overall relatedness between polymeric molecules, e.g., between nucleic acid molecules (e.g., DNA molecules and/or RNA molecules) and/or between polypeptide molecules. In some embodiments, polymeric molecules are considered to be "homologous" to one another if their sequences are at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% identical. In some embodiments, polymeric molecules are considered to be "homologous" to one another if their sequences are at least 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, or 99% similar (e.g., containing residues with related chemical properties at corresponding positions). For example, as is well known by those of ordinary skill in the art, certain amino acids are typically classified as similar to one another as "hydrophobic" or "hydrophilic" amino acids, and/or as having "polar" or "non-polar" side chains. Substitution of one amino acid for another of the same type may often be considered a "homologous" substitution. As will be understood by those skilled in the art, a variety of algorithms are available that permit comparison of sequences in order to determine their degree of homology, including by permitting gaps of designated length in one sequence relative to another when considering which residues "correspond" to one another in different sequences. Calculation of the percent homology between two nucleic acid sequences, for example, can be performed by aligning the two sequences for optimal comparison purposes (e.g., gaps can be introduced in one or both of a first and a second nucleic acid sequences for optimal alignment and non-corresponding sequences can be disregarded for comparison purposes). In certain embodiments, the length of a sequence aligned for comparison purposes is at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or substantially 100% of the length of the reference sequence. The nucleotides at corresponding nucleotide positions are then compared. When a position in the first sequence is occupied by the same nucleotide as the corresponding position in the second sequence, then the molecules are identical at that position; when a position in the first sequence is occupied by a similar nucleotide as the corresponding position in the second sequence, then the molecules are similar at that position. The percent homology between the two sequences is a function of the number of identical and similar positions shared by the sequences, taking into account the number of gaps, and the length of each gap, which needs to be introduced for optimal alignment of the two sequences. Representative algorithms and computer programs useful in determining the percent homology between two nucleotide sequences include, for example, the algorithm of Meyers and Miller (CABIOS, 1989, 4: 11-17), which has been incorporated into the ALIGN program (version 2.0) using a PAM120 weight residue table, a gap length penalty of 12 and a gap penalty of 4. The percent homology between two nucleotide sequences can, alternatively, be determined for example using the GAP program in the GCG software package using an NWSgapdna.CMP matrix.

[0025] Identity: As used herein, the term "identity" refers to the overall relatedness between polymeric molecules, e.g., between nucleic acid molecules (e.g., DNA molecules and/or RNA molecules) and/or between polypeptide molecules. Calculation of the percent identity of two nucleic acid sequences, for example, can be performed by aligning the two sequences for optimal comparison purposes (e.g., gaps can be introduced in one or both of a first and a second nucleic acid sequences for optimal alignment and non-identical sequences can be disregarded for comparison purposes). In certain embodiments, the length of a sequence aligned for comparison purposes is at least 30%, at least 40%, at least 50%, at least 60%, at least 70%, at least 80%, at least 90%, at least 95%, or substantially 100% of the length of the reference sequence. The nucleotides at corresponding nucleotide positions are then compared. When a position in the first sequence is occupied by the same nucleotide as the corresponding position in the second sequence, then the molecules are identical at that position. The percent identity between the two sequences is a function of the number of identical positions shared by the sequences, taking into account the number of gaps, and the length of each gap, which needs to be introduced for optimal alignment of the two sequences. The comparison of sequences and determination of percent identity between two sequences can be accomplished using a mathematical algorithm. For example, the percent identity between two nucleotide sequences can be determined using the algorithm of Meyers and Miller (CABIOS, 1989, 4: 11-17), which has been incorporated into the ALIGN program (version 2.0) using a PAM 120 weight residue table, a gap length penalty of 12 and a gap penalty of 4. The percent identity between two nucleotide sequences can, alternatively, be determined using the GAP program in the GCG software package using an NWSgapdna.CMP matrix.

[0026] Isolated: As used herein, the term "isolated" refers to a substance and/or entity that has been (1) separated from at least some of the components with which it was associated when initially produced (whether in nature and/or in an experimental setting), and/or (2) produced, prepared, and/or manufactured by the hand of man.

Isolated substances and/or entities may be separated from about 10%, about 20%, about 30%, about 40%, about 50%, about 60%, about 70%, about 80%, about 90%, about 91%, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more than about 99% of the other components with which they were initially associated. In some embodiments, isolated agents are about 80%, about 85%, about 90%, about 91 %, about 92%, about 93%, about 94%, about 95%, about 96%, about 97%, about 98%, about 99%, or more than about 99% pure. As used herein, a substance is "pure" if it is substantially free of other components. As used herein, calculation of percent purity of isolated substances and/or entities should not include excipients (e.g., buffer, solvent, water, etc.)

[0027] Mammal: The term "mammal" as used herein is intended to include, but is not limited to, humans, laboratory animals, domestic pets and farm animals.

[0028] Patient: As used herein, the term "patient" or "subject" refers to a human or any non-human animal (e.g., mouse, rat, rabbit, dog, cat, cattle, swine, sheep, horse or primate) to whom therapy is administered. In many embodiments, a patient is a human being. In some embodiments, a patient is a human presenting to a medical provider for diagnosis or treatment of a disease, disorder or condition. In some embodiments, a patient displays one or more symptoms or characteristics of a disease, disorder or condition. In some embodiments, a patient does not display any symptom or characteristic of a disease, disorder, or condition. In some embodiments, the disorder or condition includes cancer, or the presence of one or more tumors or neoplasms.

[0029] Pharmaceutically acceptable: The term "pharmaceutically acceptable" as used herein, refers to substances that, within the scope of sound medical judgment, are suitable for use in contact with the tissues of human beings and animals without excessive toxicity, irritation, allergic response, or other problem or complication, commensurate with a reasonable benefit/risk ratio.

[0030] Pharmaceutically acceptable carrier: As used herein, the term

"pharmaceutically acceptable carrier" means a pharmaceutically-acceptable material, composition or vehicle, such as a liquid or solid filler, diluent, excipient, or solvent encapsulating material, involved in carrying or transporting the subject compound from one organ, or portion of the body, to another organ, or portion of the body. Each carrier must be "acceptable" in the sense of being compatible with the other ingredients of the formulation and not injurious to the patient. Some examples of materials which can serve as pharmaceutically-acceptable carriers include: sugars, such as lactose, glucose and sucrose; starches, such as corn starch and potato starch; cellulose, and its derivatives, such as sodium carboxymethyl cellulose, ethyl cellulose and cellulose acetate; powdered tragacanth; malt; gelatin; talc; excipients, such as cocoa butter and suppository waxes; oils, such as peanut oil, cottonseed oil, safflower oil, sesame oil, olive oil, corn oil and soybean oil; glycols, such as propylene glycol; polyols, such as glycerin, sorbitol, mannitol and polyethylene glycol; esters, such as ethyl oleate and ethyl laurate; agar; buffering agents, such as magnesium hydroxide and aluminum hydroxide; alginic acid; pyrogen- free water; isotonic saline; Ringer's solution; ethyl alcohol; pH buffered solutions; polyesters, polycarbonates and/or polyanhydrides; and other non-toxic compatible substances employed in pharmaceutical formulations.

[0031] Pharmaceutical composition: As used herein, the term "pharmaceutical composition" refers to an active agent, formulated together with one or more pharmaceutically acceptable carriers. In some embodiments, active agent is present in unit dose amount appropriate for administration in a therapeutic regimen that shows a statistically significant probability of achieving a predetermined therapeutic effect when administered to a relevant population. In some embodiments, pharmaceutical compositions may be specially formulated for administration in solid or liquid form, including those adapted for the following: oral administration, for example, drenches (aqueous or non-aqueous solutions or suspensions), tablets, e.g., those targeted for buccal, sublingual, and systemic absorption, boluses, powders, granules, pastes for application to the tongue; parenteral administration, for example, by subcutaneous, intramuscular, intravenous or epidural injection as, for example, a sterile solution or suspension, or sustained-release formulation; topical application, for example, as a cream, ointment, or a controlled-release patch or spray applied to the skin, lungs, or oral cavity; intravaginally or intrarectally, for example, as a pessary, cream, or foam; sublingually; ocularly; transdermally; or nasally, pulmonary, and to other mucosal surfaces.

[0032] Polypeptide: As used herein, a "polypeptide", generally speaking, is a string of at least two amino acids attached to one another by a peptide bond. In some embodiments, a polypeptide may include at least 3-5 amino acids, each of which is attached to others by way of at least one peptide bond. Those of ordinary skill in the art will appreciate that polypeptides sometimes include "non-natural" amino acids or other entities that nonetheless are capable of integrating into a polypeptide chain, optionally. [0033] Protein: As used herein, the term "protein" refers to a polypeptide (i.e., a string of at least two amino acids linked to one another by peptide bonds). Proteins may include moieties other than amino acids (e.g., may be glycoproteins,

proteoglycans, etc.) and/or may be otherwise processed or modified. Those of ordinary skill in the art will appreciate that a "protein" can be a complete polypeptide chain as produced by a cell (with or without a signal sequence), or can be a characteristic portion thereof. Those of ordinary skill will appreciate that a protein can sometimes include more than one polypeptide chain, for example linked by one or more disulfide bonds or associated by other means. Polypeptides may contain L-amino acids, D- amino acids, or both and may contain any of a variety of amino acid modifications or analogs known in the art. Useful modifications include, e.g., terminal acetylation, amidation, methylation, etc. In some embodiments, proteins may comprise natural amino acids, non-natural amino acids, synthetic amino acids, and combinations thereof.

[0034] Small Molecule: In general, a "small molecule" is understood in the art to be an organic molecule that is less than about 2000 g/mol, less than about 1500 g/mol, less than about 1000 g/mol, less than about 800 g/mol, or less than about 500 g/mol. In some embodiments, small molecules are not proteins, peptides, or amino acids.

[0035] Subject: As used herein, the term "subject" or "patient" refers to any organism to which a composition of this invention may be administered, e.g., for experimental, diagnostic, prophylactic, and/or therapeutic purposes. Typical subjects include animals (e.g., mammals such as mice, rats, rabbits, non-human primates, and humans; insects; worms; etc.).

[0036] Substantial sequence homology: The phrase "substantial homology" is used herein to refer to a comparison between amino acid or nucleic acid sequences. As will be appreciated by those of ordinary skill in the art, two sequences are generally considered to be "substantially homologous" if they contain homologous residues in corresponding positions. Homologous residues may be identical residues.

Alternatively, homologous residues may be non-identical residues with appropriately similar structural and/or functional characteristics. For example, as is well known by those of ordinary skill in the art, certain amino acids are typically classified as "hydrophobic" or "hydrophilic" amino acids, and/or as having "polar" or "non-polar" side chains. Substitution of one amino acid for another of the same type may often be considered a "homologous" substitution. As is well known in this art, amino acid or nucleic acid sequences may be compared using any of a variety of algorithms, including those available in commercial computer programs such as BLASTN for nucleotide sequences and BLASTP, gapped BLAST, and PSI-BLAST for amino acid sequences. Exemplary such programs are described in Altschul, et al, Basic local alignment search tool, J. Mol. Biol, 215(3): 403-410, 1990; Altschul, et al, Methods in Enzymology; Altschul, et al, "Gapped BLAST and PSI-BLAST: a new generation of protein database search programs", Nucleic Acids Res. 25 :3389-3402, 1997;

Baxevanis, et al, Bioinformatics : A Practical Guide to the Analysis of Genes and Proteins, Wiley, 1998; and Misener, et al, (eds.), Bioinformatics Methods and Protocols (Methods in Molecular Biology, Vol. 132), Humana Press, 1999; all of the foregoing of which are incorporated herein by reference. In addition to identifying homologous sequences, the programs mentioned above typically provide an indication of the degree of homology. In some embodiments, two sequences are considered to be substantially homologous if at least 50%, at least 55%, at least 60%, at least 65%, at least 70%, at least 75%, at least 80%, at least 85%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99% or more of their corresponding residues are homologous over a relevant stretch of residues. In some embodiments, the relevant stretch is a complete sequence. In some embodiments, the relevant stretch is at least 10, at least 15, at least 20, at least 25, at least 30, at least 35, at least 40, at least 45, at least 50, at least 55, at least 60, at least 65, at least 70, at least 75, at least 80, at least 85, at least 90, at least 95, at least 100, at least 125, at least 150, at least 175, at least 200, at least 225, at least 250, at least 275, at least 300, at least 325, at least 350, at least 375, at least 400, at least 425, at least 450, at least 475, at least 500 or more residues.

[0037] Substantial identity: The phrase "substantial identity" is used herein to refer to a comparison between amino acid or nucleic acid sequences. As will be appreciated by those of ordinary skill in the art, two sequences are generally considered to be "substantially identical" if they contain identical residues in corresponding positions. As is well known in this art, amino acid or nucleic acid sequences may be compared using any of a variety of algorithms, including those available in commercial computer programs such as BLASTN for nucleotide sequences and BLASTP, gapped BLAST, and PSI-BLAST for amino acid sequences. Exemplary such programs are described in Altschul, et al., Basic local alignment search tool, J. Mol. Biol., 215(3): 403-410, 1990; Altschul, et al., Methods in Enzymology; Altschul et al., Nucleic Acids Res. 25:3389- 3402, 1997; Baxevanis et al., Bioinformatics : A Practical Guide to the Analysis of Genes and Proteins, Wiley, 1998; and Misener, et al., (eds.), Bioinformatics Methods and Protocols (Methods in Molecular Biology, Vol. 132), Humana Press, 1999. In addition to identifying identical sequences, the programs mentioned above typically provide an indication of the degree of identity. In some embodiments, two sequences are considered to be substantially identical if at least 50%, 55%, 60%, 65%, 70%, 75%, 80%, 85%, 90%, 91%, 92%, 93%, 94%, 95%, 96%o, 97%), 98%), 99%> or more of their corresponding residues are identical over a relevant stretch of residues. In some embodiments, the relevant stretch is a complete sequence. In some embodiments, the relevant stretch is at least 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95, 100, 125, 150, 175, 200, 225, 250, 275, 300, 325, 350, 375, 400, 425, 450, 475, 500 or more residues.

[0038] Therapeutically effective amount: As used herein, the term "therapeutically effective amount" means an amount of antibody agent or other therapeutic agent set forth herein that, when administered to a mammal, is effective in producing the desired therapeutic effect.

[0039] Therapeutic agent: As used herein, the phrase "therapeutic agent" refers to any agent that, when administered to a subject, has a therapeutic effect and/or elicits a desired biological and/or pharmacological effect.

[0040] Treating: As used herein, the term "treat," "treatment," or "treating" refers to any method used to partially or completely alleviate, ameliorate, relieve, inhibit, prevent, delay onset of, reduce severity of and/or reduce incidence of one or more symptoms or features of a disease, disorder, and/or condition (e.g., cancer).

[0041] Vector: As used herein, "vector" refers to a nucleic acid molecule capable of transporting another nucleic acid to which it is associated. In some embodiment, vectors are capable of extra-chromosomal replication and/or expression of nucleic acids to which they are linked in a host cell such as a eukaryotic and/or prokaryotic cell. Vectors capable of directing the expression of operatively linked genes are referred to herein as "expression vectors."

Antibody Agents

[0042] There is a need for novel therapeutic antibodies that target PDGFR .

[0043] The present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 1, the CDR2 sequence set forth in SEQ ID NO.: 2, and the CDR3 sequence set forth in SEQ ID NO.: 7 or SEQ ID NO.: 15.

[0044] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 3, the CDR2 sequence set forth in SEQ ID NO.: 5, and the CDR3 sequence set forth in SEQ ID NO.: 7.

[0045] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 4, the CDR2 sequence set forth in SEQ ID NO.: 6, and the CDR3 sequence set forth in SEQ ID NO.: 7.

[0046] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 11, the CDR2 sequence set forth in SEQ ID NO.: 13, and the CDR3 sequence set forth in SEQ ID NO.: 15.

[0047] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 12, the CDR2 sequence set forth in SEQ ID NO.: 14, and the CDR3 sequence set forth in SEQ ID NO.: 15.

[0048] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin light chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 8, the CDR2 sequence set forth in SEQ ID NO.: 9, and the CDR3 sequence set forth in SEQ ID NO.: 10.

[0049] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin light chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 16, the CDR2 sequence set forth in SEQ ID NO.: 17, and the CDR3 sequence set forth in SEQ ID NO.: 18.

[0050] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 3, the CDR2 sequence set forth in SEQ ID NO.: 5, and the CDR3 sequence set forth in SEQ ID NO.: 7, and including an immunoglobulin light chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 8, the CDR2 sequence set forth in SEQ ID NO.: 9, and the CDR3 sequence set forth in SEQ ID NO.: 10.

[0051] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 4, the CDR2 sequence set forth in SEQ ID NO.: 6, and the CDR3 sequence set forth in SEQ ID NO.: 7, and including an immunoglobulin light chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.: 8, the CDR2 sequence set forth in SEQ ID NO.: 9, and the CDR3 sequence set forth in SEQ ID NO.: 10.

[0052] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 11, the CDR2 sequence set forth in SEQ ID NO.: 13, and the CDR3 sequence set forth in SEQ ID NO.: 15, and including an immunoglobulin light chain variable domain, which includes the CDRl sequence set forth in SEQ ID NO.: 16, the CDR2 sequence set forth in SEQ ID NO. 17, and the CDR3 sequence set forth in SEQ ID NO.: 18.

[0053] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes the CDR1 sequence set forth in SEQ ID NO.: 12, the CDR2 sequence set forth in SEQ ID NO.: 14, and the CDR3 sequence set forth in SEQ ID NO.: 15, and including an immunoglobulin light chain variable domain, which includes the CDR1 sequence set forth in SEQ ID NO.: 16, the CDR2 sequence set forth in SEQ ID NO.: 17, and the CDR3 sequence set forth in SEQ ID NO.: 18.

[0054] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 19, and including an immunoglobulin light chain variable domain, which includes a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 20.

[0055] In some embodiments, the present invention provides an antibody agent, wherein the immunoglobulin heavy chain variable domain includes the sequence set forth in SEQ ID NO.: 19, and the immunoglobulin light chain variable domain includes the sequence set forth in SEQ ID NO.: 20.

[0056] In some embodiments, the present invention provides an antibody agent that binds to PDGFR , including an immunoglobulin heavy chain variable domain, which includes a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 21 , and including an immunoglobulin light chain variable domain, which includes a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 22.

[0057] In some embodiments, the present invention provides an antibody agent, wherein the immunoglobulin heavy chain variable domain includes the sequence set forth in SEQ ID NO.: 21 , and the immunoglobulin light chain variable domain includes the sequence set forth in SEQ ID NO.: 22. [0058] In some embodiments, the present invention provides a bi-specific antibody agent that binds to PDGFR and another antigen, including a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 23.

[0059] In some embodiments, the present invention provides a bi-specific antibody, including the sequence set forth in SEQ ID NO.: 23.

[0060] In some embodiments, the present invention provides a bi-specific antibody agent that binds to PDGFR and VEGFR2, including a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 28.

[0061] In some embodiments, the present invention provides a bi-specific antibody, including the sequence set forth in SEQ ID NO.: 28.

[0062] In some embodiments, the present invention provides a bi-specific antibody agent, including the sequence set forth in SEQ ID NO.: 27 and SEQ ID NO.: 28.

[0063] In some embodiments, the present invention provides an antibody agent, wherein the antibody agent binds to human PDGFR and murine PDGFRp.

[0064] In some embodiments, the present invention provides an antibody agent, wherein the antibody agent includes a humanized or human antibody, or fragment thereof.

[0065] In some embodiments, the present invention provides an antibody agent, wherein the antibody agent includes an antibody that is IgA [including IgAl or IgA2], IgD, IgE, IgG [including IgGl, IgG2, IgG3 or IgG4] or IgM

[0066] In some embodiments, the present invention provides an isolated nucleic acid encoding any of the aforesaid antibody agents.

[0067] In some embodiments, the present invention provides a nucleic acid vector including an isolated nucleic acid encoding any of the aforesaid antibody agents. [0068] In some embodiments, the present invention provides a prokaryotic or eukaryotic host cell including an isolated nucleic acid encoding any of the aforesaid antibody agents.

SEQ ID NOS/Sequences of Embodiments of the Present Invention

SEQ ID NO. Description Sequence

SEQ ID NO.: HCVD CDR1 GFTFSX l YX2MX3

1 Motif

(Xi is N or W; X₂ is H or F; X₃ is F or V)

SEQ ID NO.: HCVD CDR2 X1IX2PSGGX3TX4YADSVKG

2 Motif (Xi is V or R; X₂ is S or Y; X₃ is S or Y; X₄ is G or W)

SEQ ID NO.: PFH2 HCVD NYHMF

3 CDR1 (Kabat)

SEQ ID NO.: PFH2 HCVD GFTFSNY

4 CDR1 (Chothia)

SEQ ID NO.: PFH2 HCVD VISPSGGSTGYADSVKG

5 CDR2

(Kabat)

SEQ ID NO.: PFH2 HCVD SPSGGS

6 CDR2

(Chothia)

SEQ ID NO.: PFH2 HCVD FDGDYLWDDYRHDAFDI

7 CDR3

SEQ ID NO.: PFH2 LCVD RASQSVGSYLN

8 CDR1

SEQ ID NO.: PFH2 LCVD AAYSLQT

9 CDR2

SEQ ID NO.: PFH2 LCVD QQLNFYPFT

10 CDR3

SEQ ID NO.: PFF9 HCVD CDR1 WYFMV

11

(Kabat)

SEQ ID NO.: PFF9 HCVD CDR1 GFTFSWY

12

(Chotia)

SEQ ID NO.: PFF9 HCVD CDR2 RIYPSGGYTWYADSVKG

13 (Kabat) SEQ ID NO. Description Sequence

SEQ ID NO.: PFF9 HCVD CDR2 YPSGGY

14

(Chothia)

SEQ ID NO.: PFF9 HCVD CDR3 VS FRPKT Y Y YGS GSLTWGGMD V

15

SEQ ID NO.: PFF9 LCVD CDR1 SGDKLGDKNAY

16

SEQ ID NO.: PFF9 LCVD CDR2 QNNKRPS

17

SEQ ID NO.: PFF9 LCVD CDR3 QAWDSGVV

18

SEQ ID NO.: PFH2 HCVD E VQLLES GGGL VQPGGS LRLS C A AS GFTFSN 19 YHMFW VRQ APGKGLEW VS VIS PS GGSTG Y

ADSVKGRFTISRDNSKNTLYLQMNSLRAED TAMYYCARFDGDYLWDDYRHDAFDIWGQ GTMVTVSS

SEQ ID NO.: PFH2 LCVD DIQMTQSPLSLS AS VGDR VTITCRAS QS VGS 20 YLNWYQQKPGKAPKLLIFA A YS LQT

GVPSRFSGSGSETEFSLTISGLQPEDFATYYC QQLNFYPFTFGPGTTVDIKR

SEQ ID NO.: PFF9 HCVD E VQLLES GGGL VQPGGS LRLS C A AS GFTFS 21 WYFMVW VRQ APGKGLEW VS RIYPS GG YT

WYADSVKGRFTISRDNSKNTLYLQMNSLR AEDTA VYYCARVSFRPKTYYYGS GSLTWG GMD VWGQGTT VT VS S

SEQ ID NO.: PFF9 LCVD QSALTQPPSVSVSPGQTASIACSGDKLGDKN 22 AYWYQQKAGQSPVLIIYQNNKRPSGIPERFS

GSNSENTATLSISGTQATDEGDYYCQAWDS GVVFGGGTKLTVIGQP

SEQ ID NO.: scFv H2: anti- E VQLLES GGGL VQPGGS LRLS C A AS GFTFS

23 PDGFR N YHMFW VRQ APGKGLEW VS VIS PS GGSTG

YADSVKGRFTISRDNSKNTLYLQMNSLRAE

DTAMYYCARFDGDYLWDDYRHDAFDIWG

QGTMVTVSSGGGGSGGGGSGGGGSGGGGS

GGGGSGGGGSDIQMTQSPLSLSAS

VGDR VTITCRAS QS VGS YLNWYQQKPGKA

PKLLIFAAYSLQTGVPSRFSGSGSETEFSLTIS

GLQPEDFATYYCQQLNFYPFTFGPGTTVDIK

SEQ ID NO.: Linker 1 SGGGGSGGGGSGGGGS

24

SEQ ID NO.: Linker 2 GGGGSGGGGSGGGGSGGGGSGGGGSGGG 25 GS SEQ ID NO. Description Sequence

SEQ ID NO.: B1A1 HC E VQLLES GGGL VQPGGS LRLS C A AS GFTFS 26 WY VMGW VRQ APGKGLEW VS S I YPS GG AT

NYADSVKGRFTISRDNSKNTLYLQMNSLRA EDTAVYYCARGNYFDYWGQGTLVTVSSAS TKGPS VFPLAPS SKSTS GGTAALGCLVKD YF PEP VT VS WNS G ALTS GVHTFPA VLQS S GL Y SLS S VVT VPSS SLGTQTYICN VNHKPSNTKV DKRVEPKSCDKTHTCPPCPAPELLGGPSVFL FPPKPKDTLMIS RTPE VTC V V VD VS HEDPE V KFNWYVDGVEVHNAKTKPREEQYNSTYRV VS VLT VLHQD WLNGKE YKCKVS NKALP AP IEKTISKAKGQPREPQVYTLPPSREEMTKNQ VSLTCLVKGFYPSDIAVEWESNGQPENNYK TTPPVLDSDGSFFLYSKLTVDKSRWQQGNV FS CS VMHE ALHNHYTQKS LSLS PG

SEQ ID NO.: B1A1 LC QSVLTQPPSVSVSPGQTASITCSGEKLGDEY 27 ASWYQQKPGQSPVLVIYQDNKRPSGIPERFS

GSNSGNTATLTISGTQAMDEADYYCQAWD S S TLLFGGGTKLT VLGQPKA APS VTLFPPS S EELQANKATLVCLISDFYPGAVTVAWKADS SP VKAG VETTKPS KQS NNKY A AS S YLS LTP EQWKSHRS YS CQ VTHEGS T VEKT V APTECS

SEQ ID NO.: BlAlHC-scFvH2 E VQLLES GGGL VQPGGS LRLS C A AS GFTFS

28 WY VMGW VRQ APGKGLEW VS S I YPS GG AT

(bi-specifc) NYADSVKGRFTISRDNSKNTLYLQMNSLRA

EDTAVYYCARGNYFDYWGQGTLVTVSSAS TKGPS VFPLAPS SKSTS GGTAALGCLVKD YF PEP VT VS WNS G ALTS GVHTFPA VLQS S GL Y SLS SWT VPSS SLGTQTYICN VNHKPSNTKV DKRVEPKSCDKTHTCPPCPAPELLGGPSVFL FPPKPKDTLMIS RTPE VTC VVVDVS HEDPE V KFNWYVDGVEVHNAKTKPREEQYNSTYRV VS VLT VLHQD WLNGKE YKCKVS NKALP AP IEKTISKAKGQPREPQVYTLPPSREEMTKNQ VSLTCLVKGFYPSDIAVEWESNGQPENNYK TTPPVLDSDGSFFLYSKLTVDKSRWQQGNV FS CS VMHE ALHNHYTQKS LSLS PGS GGGGS GGGGSGGGGSEVQLLESGGGLVQPGGSLRL SCAASGFTFSNYHMFWVRQAPGKGLEWVS VISPSGGSTGYADSVKGRFTISRDNSKNTLY LQMNSLRAEDTAMYYCARFDGDYLWDDY RHD AFDrWGQGTM VT VS SGGGGSGGGGSG GGGSGGGGSGGGGSGGGGSDIQMTQSPLSL S AS VGDR VTITCRAS QS VGS YLNW YQQKPG KAPKLLIFAAYSLQTGVPSRFSGSGSETEFSL TIS GLQPEDFAT Y YCQQLNF YPFTFGPGTT V SEQ ID NO. Description Sequence

DIK

Preparation of Antibody Agents

[0069] The manufacture of antibodies having desired CRDs and framework regions is generally known in the art and described in, for example, Strohl & Strohl,

Therapeutic Antibody Engineering, Woodhead Publishing Limited 2012.

[0070] Methods for preparing antibody fragments are also well known in the art. For example, monovalent Fab fragments, which lack the heavy chain hinge region can be prepared from whole immunoglobulin by proteolytic digestion with papain.

Bivalent F(ab')2 fragments, which retain the heavy chain hinge region can be prepared by proteolytic digestion with pepsin.

[0071] Methods for preparing bi-specific antibody agents (e.g., bi-specific antibody) are also well known in the art. Exemplary vectors for transient expression in HEK293 cells in this regard are pBhl (Dyax) and pcDNA™ 3.4 TOPO^® vector (Thermo Fisher Scientific). Exemplary vectors for stable expression in mammalian cells are pCHO.l in CHO-S (Thermo Fisher Scientific) and GS vector in CHO-K (Lonza). See also the following references (all of which are incorporated herein by reference in their entirety): Lu D. and Zhu Z. (2014); Construction and production of an IgG-like tetravalent bispecific antibody, IgG-single-chain Fv fusion. Human

Monoclonal antibodies, methods and protocols; Humanna press; ISSN 1064-3745; Marvin J.S., Zhu Z. (2006) Bispecific antibodies for dual-modality cancer therapy: killing twosignaling cascades with one stone. Curr. Opin. Drug Discov. Devel. 9, 184- 193; Lu, D., Zhang, H., Koo, H., et al. (2005) A fully human recombinant IgG-like bispecific antibody to both the epidermal growth factor receptor and the insulin- like growth factor receptor for enhanced antitumor activity. J. Biol. Chem. 280, 19665- 19672; Demarest S.J (2011) Emerging antibody combinations in oncology. mAbs 3, 338-351; Spiess C, Zhai Q., Carter P. (2015) Alternative molecular formats and therapeutic applications for bispecific antibodies. Molecular Immunology 67, 95-106; and Croasdale R., et al. (2012) Development of tetravalent IgGl dual targeting IGF-IR- EGFR antibodies with potent tumor inhibition. Archives of Biochem. and Biophys. 526, 206-218.

[0072] Also provided herein are nucleic acids encoding antibodies and functional fragments thereof, vectors, host cells and expression systems. The nucleic acids encoding such antibodies and functional fragments thereof may be, e.g., DNA, cDNA, RNA, synthetically produced DNA or RNA, or a recombinantly produced chimeric nucleic acid molecule comprising any of those polynucleotides either alone or in combination. For example, provided is an expression vectors containing a

polynucleotide sequence encoding an antibody described herein operably linked to expression control sequences suitable for expression in a eukaryotic and/or prokaryotic host cell. A variety of expression vectors have been developed for the efficient synthesis of antibodies and fragments in prokaryotic cells such as bacteria and eukaryotic systems, including but not limited to yeast and mammalian cell culture systems have been developed. The vectors can comprise segments of chromosomal, non-chromosomal and synthetic DNA sequences.

[0073] Any suitable expression vector can be used. For example, prokaryotic cloning vectors include plasmids from E. coli, such as colEl , pCRl, pBR322, pMB9, pUC, pKSM, and RP4. Prokaryotic vectors also include derivatives of phage DNA such as Ml 3 and other filamentous single- stranded DNA phages. An example of a vector useful in yeast is the 2μ plasmid. Suitable vectors for expression in mammalian cells include well-known derivatives of SV40, adenovirus, retro virus-derived DNA sequences and shuttle vectors derived from combination of functional mammalian vectors, such as those described above, and functional plasmids, e.g., pLenti6.. 5- DEST®. pT-Rex™-DEST31®, pGene/V5-HispGene/V5 -His® (Life Technologies, Nofwalk, CT) .

[0074] Additional eukaryotic expression vectors are known in the art (e.g., P.J. Southern and P. Berg, J. Mol. Appl. Genet., 1 , 327-341 (1982); Subramani et al., Mol. Cell. Biol., 1 : 854-864 (1981); Kaufmann and Sharp, "Amplification And Expression of Sequences Cotransfected with a Modular Dihydrofolate Reductase Complementary DNA Gene," J. Mol. Biol. 159, 601-621 (1982); Kaufmann and Sharp, Mol. Cell. Biol. 159, 601-664 (1982); Scahill et al., "Expression And Characterization Of The Product Of A Human Immune Interferon DNA Gene In Chinese Hamster Ovary Cells," Proc. Nat'l Acad. Sci. USA 80, 4654-4659 (1983); Urlaub and Chasin, Proc. Nat'l Acad. Sci. USA 77, 4216-4220, (1980).

[0075] The expression vectors may contain at least one expression control sequence that is operatively linked to the DNA sequence or fragment to be expressed. The control sequence is inserted in the vector in order to control and to regulate the expression of the cloned DNA sequence. Examples of useful expression control sequences are the lac system, the trp system, the tac system, the trc system, major operator and promoter regions of phage lambda, the control region of fd coat protein, the glycolytic promoters of yeast, e.g., the promoter for 3-phosphoglycerate kinase, the promoters of yeast acid phosphatase, e.g., Pho5, the promoters of the yeast alpha- mating factors, and promoters derived from cytomegalovirus, polyoma, adenovirus, retrovirus, and simian virus, e.g., the early and late promoters or SV40, and other sequences known to control the expression of genes of prokaryotic or eukaryotic cells and their viruses or combinations thereof. Other expression control sequences that may be used include DNA regulatory sequences from the Chinese hamster elongation factor- la (CHEF1) gene (Running Deer & Allison, 2004, Biotechnol. Prog. 20:880- 889; U.S. Patent No. 5,888,809).

[0076] Also provided are recombinant host cells containing the expression vectors previously described. Antibodies or antigen-binding portions thereof set forth herein can be expressed in cell lines other than in hybridomas. Nucleic acids, which comprise a sequence encoding a polypeptide as described herein, can be used for transformation of a suitable mammalian host cell.

[0077] Cell lines of particular preference are selected based on high level of expression, constitutive expression of protein of interest and minimal contamination from host proteins. Mammalian cell lines available as hosts for expression are well known in the art and include many immortalized cell lines, such as but not limited to, NS0 cells, Chinese Hamster Ovary (CHO) cells, Baby Hamster Kidney (BHK) cells and many others. In some embodiments, the cell is a myeloma cell, e.g., SP2/0, which can be transfected and grown in culture of in the peritoneal cavity of a mouse where high concentrations of IgG can be recovered from ascites fluid. Suitable additional eukaryotic cells include yeast and other fungi. Useful prokaryotic hosts include, for example, E. coli, such as E. coli SG-936, E. coli HB 101, E. coli W3110, E. coli X1776, E. coli X2282, E. coli DHI, and E. coli MRCl, Pseudomonas, Bacillus, such as Bacillus subtilis, and Streptomyces.

[0078] These present recombinant host cells can be used to produce an antibody, or antigen-binding portion thereof, by culturing the cells under conditions permitting expression of the antibody or fragment thereof and purifying the antibody or fragment thereof from the host cell or medium surrounding the host cell.

[0079] The transformed hosts can be grown in fermentors and cultured according to techniques known in the art. Once the desired level of expression of the antibodies is reached, the antibodies can be purified according to standard procedures of the art, including ammonium sulfate precipitation, purification on affinity columns, column chromatography, gel electrophoresis and the like. For use in the therapeutic methods described herein, it is preferred that the antibodies be purified to at least 90%, 95%, 98%, or 99% purity.

[0080] Targeting of the expressed antibody or fragment for secretion in the recombinant host cells can be facilitated by inserting a signal or secretory leader peptide-encoding sequence (see, Shokri et al., Appl Microbiol Biotechnol. 60(6):654- 64 (2003), Nielsen et al., Prot. Eng. 10:1-6 (1997) and von Heinje et al., Nucl. Acids Res. 14:4683-4690 (1986)) at the 5' end of the antibody-encoding gene of interest. These secretory leader peptide elements can be derived from either prokaryotic or eukaryotic sequences. Accordingly suitably, secretory leader peptides are used, being amino acids joined to the N-terminal end of a polypeptide to direct movement of the polypeptide out of the host cell cytosol and secretion into the medium.

[0081] The antibodies or antigen-binding portions thereof can be fused to additional amino acid residues. Such amino acid residues can be a peptide tag, perhaps to facilitate isolation. Other amino acid residues for homing of the antibodies to specific organs or tissues are also contemplated. [0082] In some embodiments, the antibody or antigen-binding portion thereof is conjugated to one or more effector molecules, which provide some desirable property (e.g., increased serum half-life) to the antibody or antigen-binding portion thereof. In a particular embodiment, the antibody or antigen-binding portion thereof is conjugated to polyethyleneglycol (PEG). The PEG may be attached to any amino acid side chain or terminal amino acid functional group, e.g., a free amino, imino, thiol, hydroxyl, or carboxyl group. Methods of attaching PEG to antibodies are known in the art and may be employed. See, e.g., European Patent Application EP 0948544; European Patent Application EP1090037; "Poly(ethyleneglycol) Chemistry, Biotechnical and

Biomedical Applications," 1992, J. Milton Harris (ed), Plenum Press, New York; "Poly( ethyleneglycol) Chemistry and Biological Applications," 1997, J. Milton Harris & S. Zalipsky (eds), American Chemical Society, Washington DC; "Bioconjugation Protein Coupling Techniques for the Biomedical Sciences," 1998, M. Aslam & A. Dent, Grove Publishers, New York; or Chapman, A. 2002, Advanced Drug Delivery Reviews 2002, 54:531-545.

[0083] In another embodiment, an antibody or antigen-binding portion thereof as set forth herein is made by expressing a nucleic acid encoding the antibody in a transgenic animal, such that the antibody is expressed and can be recovered. For example, the antibody can be expressed in a tissue specific manner that facilitates recovery and purification. In one such embodiment, an antibody of the expressed in the mammary gland for secretion during lactation. Transgenic animals, include but are not limited to mice, goat, and rabbit.

Compositions

[0084] In some embodiments, the present invention provides a pharmaceutical composition including any of the aforesaid antibody agents, and a pharmaceutically acceptable carrier.

[0085] Pharmaceutical compositions provided here may be provided in a sterile injectable form (e.g., a form that is suitable for subcutaneous injection or intravenous infusion) and/or other liquid dosage form that is suitable for injection. In some embodiments, pharmaceutical compositions are provided as powders (e.g., lyophilized and/or sterilized), optionally under vacuum, which are reconstituted with an aqueous diluent (e.g., water, buffer, salt solution, etc.) prior to injection. In some embodiments, pharmaceutical compositions are diluted and/or reconstituted in water, sodium chloride solution, sodium acetate solution, benzyl alcohol solution, phosphate buffered saline, etc.

[0086] The pharmaceutical compositions presented herein as the present invention include not only injectable, but also all commonly known non-injectable compositions.

[0087] In some embodiments, provided pharmaceutical compositions comprise one or more pharmaceutically acceptable excipients (e.g., preservative, inert diluent, dispersing agent, surface active agent and/or emulsifier, buffering agent, etc.). In some embodiments, appropriate excipients for use in provided pharmaceutical compositions may, for example, include one or more pharmaceutically acceptable solvents, dispersion media, granulating media, diluents, or other liquid vehicles, dispersion or suspension aids, surface active agents and/or emulsifiers, isotonic agents, thickening or emulsifying agents, preservatives, solid binders, lubricants, disintegrating agents, binding agents, preservatives, buffering agents and the like, as suited to the particular dosage form desired. Alternatively or additionally, pharmaceutically acceptable excipients such as cocoa butter and/or suppository waxes, coloring agents, coating agents, sweetening, flavoring, and/or perfuming agents can be utilized.

[0088] In some embodiments, pharmaceutical compositions comprise one or more preservatives. In some embodiments, pharmaceutical compositions comprise no preservative. In some embodiments, pharmaceutical compositions are provided in a form that can be refrigerated and/or frozen. In some embodiments, pharmaceutical compositions are provided in a form that cannot be refrigerated and/or frozen. In some embodiments, reconstituted solutions and/or liquid dosage forms may be stored for a certain period of time after reconstitution (e.g., 2 hours, 12 hours, 24 hours, 2 days, 5 days, 7 days, 10 days, 2 weeks, a month, two months, or longer). In some

embodiments, storage of compositions for longer than the specified time results in degradation of active agents. [0089] In some embodiments, injectable preparations, for example, sterile aqueous or oleaginous suspensions, may be formulated according to known methods using suitable dispersing agents, wetting agents, and/or suspending agents. Sterile liquid preparations may be, for example, solutions, suspensions, and/or emulsions in nontoxic parenterally acceptable diluents and/or solvents, for example, as a solution in 1,3- butanediol. Among the acceptable vehicles and solvents that may be employed, for example, are water, Ringer's solution, U.S. P., and isotonic sodium chloride solution. Sterile, fixed oils are conventionally employed as a solvent or suspending medium. For this purpose any bland fixed oil can be employed including synthetic mono- or diglycerides. Fatty acids such as oleic acid can be used in the preparation of liquid formulations.

[0090] Liquid formulations can be sterilized, for example, by filtration through a bacterial-retaining filter, and/or by incorporating sterilizing agents in the form of sterile solid compositions which can be dissolved or dispersed in sterile water or other sterile injectable medium prior to use.

[0091] Pharmaceutical compositions described herein may be prepared by any method known or hereafter developed in the art of pharmacology. In some embodiments, such preparatory methods include the step of bringing active ingredient into association with one or more excipients and/or one or more other accessory ingredients, and then, if necessary and/or desirable, shaping and/or packaging the product into a desired single- or multi-dose unit.

[0092] A pharmaceutical composition in accordance with the invention may be prepared, packaged, and/or sold in bulk, as a single unit dose, and/or as a plurality of single unit doses. As used herein, a "unit dose" is discrete amount of the

pharmaceutical composition comprising a predetermined amount of the active ingredient. The amount of the active ingredient is generally equal to a dose which would be administered to a subject and/or a convenient fraction of such a dose such as, for example, one-half or one-third of such a dose.

[0093] Relative amounts of active ingredient, pharmaceutically acceptable excipient, and/or any additional ingredients in a pharmaceutical composition in accordance with the invention may vary, depending upon the identity, size, and/or condition of the subject treated and/or depending upon the route by which the composition is to be administered. By way of example, the composition may comprise between 0.1% and 100% (w/w) active ingredient.

[0094] Pharmaceutical compositions of the present invention may additionally comprise one or more solvents, dispersion media, diluents, or other liquid vehicles, dispersion or suspension aids, surface active agents, isotonic agents, thickening or emulsifying agents, preservatives, solid binders, lubricants and the like, as suited to the particular dosage form desired. Remington's The Science and Practice of Pharmacy, 21st Edition, A. R. Gennaro, (Lippincott, Williams & Wilkins, Baltimore, MD, 2006) discloses various excipients used in formulating pharmaceutical compositions and known techniques for the preparation thereof. Except insofar as any conventional excipient medium is incompatible with a substance or its derivatives, such as by producing any undesirable biological effect or otherwise interacting in a deleterious manner with any other component(s) of the pharmaceutical composition, its use is contemplated to be within the scope of this invention.

Use for Treatment

[0095] In some embodiments, the present invention provides a method of neutralizing activation of human PDGFR , or murine PDGFR , including contacting a cell with an effective amount of any of the aforesaid antibody agents.

[0096] In some embodiments, the present invention provides a method inhibiting phosphorylation of human PDGFR , or murine PDGFR , including contacting a cell with an effective amount of any of the aforesaid antibody agents.

[0097] In some embodiments, the present invention provides a method of reducing tumor growth, including administering to a subject an effective amount of any of the aforesaid antibody agents.

[0098] In some embodiments, the present invention provides a method of treating a neoplastic disease in a subject, including administering to a subject an effective amount of any of the aforesaid antibody agents, wherein the neoplastic diseases is selected from the group consisting of colon cancer, liver cancer, stomach cancer, skin cancer, brain cancer, breast cancer, ovarian cancer, uterine cancer, cervical cancer, bone cancer, leukemia, lymphoma, and lung cancer.

[0099] In some embodiments, the present invention provides a method which further includes administering to the subject an effective amount of a PDGFR antagonist other than any of the PDGFR agents including an amino acid sequence set forth in any one of SEQ ID NO.: 1-22.

[00100] In some embodiments, the present invention provides a method wherein the patient is a human.

[00101] Antibody agents in accordance with the invention and pharmaceutical compositions thereof in accordance with the present invention may be administered according to any appropriate route and regimen. In some embodiments, the exact amount administered may vary from subject to subject, depending on one or more factors as is well known in the medical arts. Such factors may include, for example, one or more of species, age, general condition of the subject, severity of the infection, particular composition, its mode of administration, its mode of activity, the disorder being treated and the severity of the disorder; the activity of the specific DV antibody agent employed; the specific pharmaceutical composition administered; the half-life of the composition after administration; the age, body weight, general health, sex, and diet of the subject; the time of administration, route of administration, and rate of excretion of the specific compound employed; the duration of the treatment; drugs used in combination or coincidental with the specific compound employed and the like.

Pharmaceutical compositions may be formulated in dosage unit form for ease of administration and uniformity of dosage. It will be understood, however, that the total daily usage of the compositions of the present invention will be decided by the attending physician within the scope of sound medical judgment.

[00102] Pharmaceutical compositions of the present invention may be administered by any route, as will be appreciated by those skilled in the art. In some embodiments, pharmaceutical compositions of the present invention are administered by oral (PO), intravenous (IV), intramuscular (IM), intra- arterial, intramedullary, intrathecal, subcutaneous (SQ), intraventricular, transdermal, interdermal, intradermal, rectal (PR), vaginal, intraperitoneal (IP), intragastric (IG), topical (e.g., by powders, ointments, creams, gels, lotions, and/or drops), mucosal, intranasal, buccal, enteral, vitreal, sublingual; by intratracheal instillation, bronchial instillation, and/or inhalation; as an oral spray, nasal spray, and/or aerosol, and/or through a portal vein catheter.

[00103] In specific embodiments, DV antibody agents in accordance with the present invention and/or pharmaceutical compositions thereof may be administered intravenously, for example, by intravenous infusion. In specific embodiments, antibody agents in accordance with the present invention and/or pharmaceutical compositions thereof may be administered by intramuscular injection. In specific embodiments, antibody agents in accordance with the present invention and/or pharmaceutical compositions thereof may be administered by subcutaneous injection. In specific embodiments, antibody agents in accordance with the present invention and/or pharmaceutical compositions thereof may be administered via portal vein catheter. However, the invention encompasses the delivery of antibody agents in accordance with the present invention and/or pharmaceutical compositions thereof by any appropriate route taking into consideration likely advances in the sciences of drug delivery.

[00104] In certain embodiments, antibody agents in accordance with the present invention and/or pharmaceutical compositions thereof in accordance with the invention may be administered at dosage levels sufficient to deliver from about 0.001 mg/kg to about 100 mg/kg, from about 0.01 mg/kg to about 50 mg/kg, from about 0.1 mg/kg to about 40 mg/kg, from about 0.5 mg/kg to about 30 mg/kg, from about 0.01 mg/kg to about 10 mg/kg, from about 0.1 mg/kg to about 10 mg/kg, or from about 1 mg/kg to about 25 mg/kg of subject body weight per day to obtain the desired therapeutic effect. The desired dosage may be delivered more than three times per day, three times per day, two times per day, once per day, every other day, every third day, every week, every two weeks, every three weeks, every four weeks, every two months, every six months, or every twelve months. In certain embodiments, the desired dosage may be delivered using multiple administrations (e.g., two, three, four, five, six, seven, eight, nine, ten, eleven, twelve, thirteen, fourteen, or more administrations). [00105] Throughout this application, various publications are referenced. These publications are hereby incorporated into this application by reference in their entireties to more fully describe the state of the art to which this invention pertains.

[00106] The following examples further illustrate the invention, but should not be construed to limit the scope of the invention in any way.

EXAMPLES

EXAMPLE 1

[00107] Anti-PDGFRp antibodies PFH2 and PFF9 (see FIG. 2) were identified by screening phage display libraries (κ lib: 1.5 x 10¹⁰; λ lib: 2.0 x 10¹⁰), using human PDGFRp (see FIG. 1).

EXAMPLE 2

[00108] The binding of antibodies PFH2 and PFF9 to soluble and cell-expressed PDGFR was characterized by standard methods commonly known in the art. See, e.g., Antibodies: A Laboratory Manual, Second edition; Edited by Edward A.

Greenfield; Cold Spring Harbor Laboratory Press 2014 (which is incorporated herein by reference in its entirety). These studies revealed that antibodies PFH2 and PFF9 specifically bind to human, murine and rat PDGFR , whereas the control antibody binds only to human PDGFRP (see FIG. 3).

EXAMPLE 3

[00109] Additional studies were conducted which revealed that antibodies PFH2 and PFF9 specifically bind to the ligand binding domain (domains 1-3) of human PDGFRP, and that antibodies PFH2 and PFF9 can specifically block binding of PDGFbb to PDGFRp. These studies were conducted using standard methods commonly known in the art (see FIG. 4). See, e.g., Antibodies: A Laboratory Manual, Second edition; Edited by Edward A. Greenfield; Cold Spring Harbor Laboratory Press 2014 (which is incorporated herein by reference in its entirety).

EXAMPLE 4

[00110] Additional studies were conducted which revealed that antibodies PFH2 and PFF9 inhibit phosphorylation of PDGFR and downstream signaling molecule map- kinase (MAPK) in response to stimulation by PDGFbb. These studies were conducted using PDGFR -expressing 293 cells and standard immune-precipitation (IP) methods commonly known in the art (see FIG. 5). See, e.g., Antibodies: A Laboratory Manual, Second edition; Edited by Edward A. Greenfield; Cold Spring Harbor Laboratory Press 2014 (which is incorporated herein by reference in its entirety).

EXAMPLE 5

[00111] The variable light and heavy chain domains of antibody PFH2 were used to construct a scFv separated by a linker (Linker 2 in FIG. 7), using recombinant DNA technologies and expression tools commonly known in the art. The PFH2 scFv (H2 in FIG. 7) was then combined with the heavy chain of anti-VEGFR2 antibody BlAl via a linker (Linker 1 in FIG. 7), using principally similar technology.

Claims

CLAIMS What is claimed is:

1. An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

1, the CDR2 sequence set forth in SEQ ID NO.: 2, and the CDR3 sequence set forth in SEQ ID NO.: 7 or SEQ ID NO.: 15.

2, An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

3, the CDR2 sequence set forth in SEQ ID NO.: 5, and the CDR3 sequence set forth in SEQ ID NO.: 7.

3. An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

4, the CDR2 sequence set forth in SEQ ID NO.: 6, and the CDR3 sequence set forth in SEQ ID NO.: 7.

4. An antibody agent that binds to PDGFRP, comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

11, the CDR2 sequence set forth in SEQ ID NO.: 13, and the CDR3 sequence set forth in SEQ ID NO.: 15.

5. An antibody agent that binds to PDGFRP, comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

12, the CDR2 sequence set forth in SEQ ID NO.: 14, and the CDR3 sequence set forth in SEQ ID NO.: 15.

6. An antibody agent that binds to PDGFRP, comprising an immunoglobulin light chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.: 8, the CDR2 sequence set forth in SEQ ID NO.: 9, and the CDR3 sequence set forth in SEQ ID NO.: 10.

7. An antibody agent that binds to PDGFRP, comprising an immunoglobulin light chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.: 16, the CDR2 sequence set forth in SEQ ID NO.: 17, and the CDR3 sequence set forth in SEQ ID NO.: 18.

8. An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

3, the CDR2 sequence set forth in SEQ ID NO.: 5, and the CDR3 sequence set forth in SEQ ID NO.: 7, and comprising an immunoglobulin light chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.: 8, the CDR2 sequence set forth in SEQ ID NO.: 9, and the CDR3 sequence set forth in SEQ ID NO.: 10.

9. An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

4, the CDR2 sequence set forth in SEQ ID NO.: 6, and the CDR3 sequence set forth in SEQ ID NO.: 7, and comprising an immunoglobulin light chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.: 8, the CDR2 sequence set forth in SEQ ID NO.: 9, and the CDR3 sequence set forth in SEQ ID NO.: 10.

10. An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

11. the CDR2 sequence set forth in SEQ ID NO.: 13, and the CDR3 sequence set forth in SEQ ID NO.: 15, and comprising an immunoglobulin light chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.: 16, the CDR2 sequence set forth in SEQ ID NO.: 17, and the CDR3 sequence set forth in SEQ ID NO.: 18.

11. An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.:

12, the CDR2 sequence set forth in SEQ ID NO.: 14, and the CDR3 sequence set forth in SEQ ID NO.: 15, and comprising an immunoglobulin light chain variable domain, which comprises the CDRl sequence set forth in SEQ ID NO.: 16, the CDR2 sequence set forth in SEQ ID NO.: 17, and the CDR3 sequence set forth in SEQ ID NO.: 18.

12. An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 19, and an immunoglobulin light chain variable domain, which comprises a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 20.

13. The antibody agent of claim 12, wherein the immunoglobulin heavy chain variable domain comprises the sequence set forth in SEQ ID NO.: 19, and the immunoglobulin light chain variable domain comprises the sequence set forth in SEQ ID NO.: 20.

14. An antibody agent that binds to PDGFR , comprising an immunoglobulin heavy chain variable domain, which comprises a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 21, and an immunoglobulin light chain variable domain, which comprises a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 22.

15. The antibody agent of claim 13, wherein the immunoglobulin heavy chain variable domain comprises the sequence set forth in SEQ ID NO.: 21, and the immunoglobulin light chain variable domain comprises the sequence set forth in SEQ ID NO.: 22.

16. A bi-specific antibody agent that binds to PDGFR and another antigen, comprising a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 23.

17. The bi-specific antibody agent of claim 16, comprising the sequence set forth in SEQ ID NO.: 23.

18. A bi-specific antibody agent that binds to PDGFR and VEGFR2, comprising a sequence at least 85, 90 or 95% identical to the sequence set forth in SEQ ID NO.: 28.

19. The bi-specific antibody agent of claim 18, comprising the sequence set forth in SEQ ID NO.: 28.

20. The bi-specific antibody agent of claim 18, comprising the sequence set forth in SEQ ID NO.: 27 and SEQ ID NO.: 28.

21. The antibody agent of any one of claims 1-20, wherein the antibody agent binds to human PDGFRP and murine PDGFRP .

22. The antibody agent of any one of claims 1-21, wherein the antibody agent comprises a humanized or human antibody, or fragment thereof.

23. An isolated nucleic acid encoding the antibody agent of any one of claims 1-22.

24. A nucleic acid vector comprising an isolated nucleic acid according to claim 23.

25. A prokaryotic or eukaryotic host cell comprising an isolated nucleic acid according to claim 23.

26. A pharmaceutical composition comprising an antibody agent of any one of claims 1-22, and a pharmaceutically acceptable carrier.

27. A method of neutralizing activation of human PDGFR , or murine PDGFR , comprising contacting a cell with an effective amount of an antibody agent of any one of claims 1-22.

28. A method inhibiting phosphorylation of human PDGFR , or murine PDGFR , comprising contacting a cell with an effective amount of an antibody agent of any one of claims 1-22.

29. A method of reducing tumor growth, comprising administering to a subject an effective amount of an antibody agent of any one of claims 1-22.

30. A method of treating a neoplastic disease in a subject, comprising administering to a subject an effective amount of an antibody agent of any one of claims 1-22, wherein the neoplastic diseases is selected from the group consisting of colon cancer, liver cancer, stomach cancer, skin cancer, brain cancer, breast cancer, ovarian cancer, uterine cancer, cervical cancer, bone cancer, leukemia, lymphoma, and lung cancer.

31. The method of any one of claims 29-30, which further comprises administering to the subject an effective amount of a PDGFR antagonist other than PDGFR agents including an amino acid sequence set forth in any one of SEQ ID NO.: 1-22.

32. The method of any one of claims 29-31, wherein the patient is a human.