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US20140056879A1 - Fc variants that extend antibody half-life - Google Patents

Fc variants that extend antibody half-life Download PDF

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US20140056879A1
US20140056879A1 US13/973,934 US201313973934A US2014056879A1 US 20140056879 A1 US20140056879 A1 US 20140056879A1 US 201313973934 A US201313973934 A US 201313973934A US 2014056879 A1 US2014056879 A1 US 2014056879A1
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antibody
antibodies
variant
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Gregory A. Lazar
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Xencor Inc
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Xencor Inc
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Priority claimed from US11/274,065 external-priority patent/US9200079B2/en
Priority claimed from US11/436,266 external-priority patent/US20070135620A1/en
Priority claimed from US11/932,151 external-priority patent/US8802820B2/en
Priority claimed from US12/341,769 external-priority patent/US8367805B2/en
Application filed by Xencor Inc filed Critical Xencor Inc
Assigned to XENCOR, INC. reassignment XENCOR, INC. ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: LAZAR, GREGORY A.
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    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/22—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against growth factors ; against growth regulators
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents
    • A—HUMAN NECESSITIES
    • A61—MEDICAL OR VETERINARY SCIENCE; HYGIENE
    • A61P—SPECIFIC THERAPEUTIC ACTIVITY OF CHEMICAL COMPOUNDS OR MEDICINAL PREPARATIONS
    • A61P35/00—Antineoplastic agents
    • A61P35/02—Antineoplastic agents specific for leukemia
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/24—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against cytokines, lymphokines or interferons
    • C07K16/241—Tumor Necrosis Factors
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/2863—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants against receptors for growth factors, growth regulators
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/18—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans
    • C07K16/28—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants
    • C07K16/2866—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against material from animals or humans against receptors, cell surface antigens or cell surface determinants against receptors for cytokines, lymphokines, interferons
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K16/00—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies
    • C07K16/42—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against immunoglobulins
    • C07K16/4283—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against immunoglobulins against an allotypic or isotypic determinant on Ig
    • C07K16/4291—Immunoglobulins [IGs], e.g. monoclonal or polyclonal antibodies against immunoglobulins against an allotypic or isotypic determinant on Ig against IgE
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/20—Immunoglobulins specific features characterized by taxonomic origin
    • C07K2317/24—Immunoglobulins specific features characterized by taxonomic origin containing regions, domains or residues from different species, e.g. chimeric, humanized or veneered
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/50—Immunoglobulins specific features characterized by immunoglobulin fragments
    • C07K2317/52—Constant or Fc region; Isotype
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2317/00—Immunoglobulins specific features
    • C07K2317/90—Immunoglobulins specific features characterized by (pharmaco)kinetic aspects or by stability of the immunoglobulin
    • C07K2317/94—Stability, e.g. half-life, pH, temperature or enzyme-resistance
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07K—PEPTIDES
    • C07K2319/00—Fusion polypeptide
    • C07K2319/30—Non-immunoglobulin-derived peptide or protein having an immunoglobulin constant or Fc region, or a fragment thereof, attached thereto

Definitions

  • the present application relates to optimized IgG immunoglobulin variants that extend antibody half-life in vivo, and their application, particularly for therapeutic purposes.
  • Antibodies are immunological proteins that bind a specific antigen. In most mammals, including humans and mice, antibodies are constructed from paired heavy and light polypeptide chains. Each chain is made up of individual immunoglobulin (Ig) domains, and thus the generic term immunoglobulin is used for such proteins. Each chain is made up of two distinct regions, referred to as the variable and constant regions. The light and heavy chain variable regions show significant sequence diversity between antibodies, and are responsible for binding the target antigen. The constant regions show less sequence diversity, and are responsible for binding a number of natural proteins to elicit important biochemical events.
  • IgA which includes subclasses IgA1 and IgA2
  • IgD which includes subclasses IgA1 and IgA2
  • IgE which includes subclasses IgG1, IgG2, IgG3, and IgG4
  • IgM immunoglobulin M
  • the distinguishing feature between these antibody classes is their constant regions, although subtler differences may exist in the V region, IgG antibodies are tetrameric proteins composed of two heavy chains and two light chains.
  • the IgG heavy chain is composed of four immunoglobulin domains linked from N- to C-terminus in the order VH—CH1-CH2-CH3, referring to the heavy chain variable domain, heavy chain constant domain 1, heavy chain constant domain 2, and heavy chain constant domain 3 respectively (also referred to as VH—C ⁇ 1-C ⁇ 2-C ⁇ 3, referring to the heavy chain variable domain, constant gamma 1 domain, constant gamma 2 domain, and constant gamma 3 domain respectively).
  • the IgG light chain is composed of two immunoglobulin domains linked from N- to C-terminus in the order VL-CL, referring to the light drain variable domain and the light chain constant domain respectively.
  • FcRn a site on Fc between the C ⁇ 2 and C ⁇ 3 domains mediates interaction with the neonatal receptor FcRn. Binding to FcRn recycles endocytosed antibody from the endosome back to the bloodstream (Raghavan et al., 1996, Annu Rev Cell Dev Biol 12:181-220; Ghetie et al., 2000, Annu Rev Immunol 18:739-766, both entirely incorporated by reference). This process, coupled with preclusion of kidney filtration due to the large size of the full-length molecule, results in favorable antibody serum half-lives ranging from one to three weeks. Binding of Fc to FcRn also plays a key role in antibody transport.
  • the binding site on Fc for FcRn is also the site at which the bacterial proteins A and G bind.
  • the tight binding by these proteins is typically exploited as a means to purify antibodies by employing protein A or protein G affinity chromatography during protein purification.
  • the fidelity of this region on Fc is important for both the clinical properties of antibodies and their purification.
  • the FcRn receptor is also responsible for the transfer of IgG to the neonatal gut and to the lumen of the intestinal epithelia in adults (Ghetie and Ward, Annu. Rev. Immunol, 2000, 18:739-766; Yoshida et al., Immunity, 2004, 20(6):769-783, both entirely incorporated by reference).
  • Antibodies have serum half-lives in vivo ranging from one to three weeks. This favorable property is due to the preclusion of kidney filtration due to the large size of the full-length molecule, and interaction of the antibody Fc region with the neonatal Fc receptor FcRn. Binding to FcRn recycles endocytosed antibody from the endosome back to the bloodstream (Raghavan et al., 1996, Annu Rev Cell Dev Biol 12:181-220; Ghetie et al., 2000, Annu Rev Immunol 18:739-766, both entirely incorporated by reference).
  • the antibody may determine its clearance rate (e.g. stability and half-life) in vivo.
  • clearance rate e.g. stability and half-life
  • factors that contribute to clearance and half-life are serum aggregation, enzymatic degradation in the serum, inherent immunogenicity of the antibody leading to clearing by the immune system, antigen-mediated uptake, FcR (non-FcRn) mediated uptake and non-serum distribution (e.g. in different tissue compartments).
  • one problem to be solved is to increase serum half life of antibodies by altering the constant domains, thus allowing the same constant regions to be used with different antigen binding sequences, e.g. the variable regions including the CDRs, and minimizing the possibility of immunogenic alterations.
  • providing antibodies with constant region variants with extended half-life provides a modular approach to improving the pharmacokinetic properties of antibodies, as described herein.
  • the possibility of immunogenicity resulting from the FcRn variants is significantly reduced by importing variants from different IgG isotypes such that serum half-life is increased without introducing significant immunogenicity.
  • the present invention provides an antibody comprising a variant Fc region as compared to a parent Fc region, wherein the variant Fc region comprises a first mutation which is a serine at position 434 and a second mutation selected from the group: an isoleucine at position 311, a valine at position 311, an isoleucine at position 436, and a valine at position 436.
  • the antibody has increased serum half-life as compared to an antibody comprising the parent Fc region, wherein numbering is according to the EU index.
  • the antibody has increased binding affinity to a human FcRn receptor as compared to an antibody comprising the parent Fc region, wherein numbering is according to the EU index.
  • the present invention provides nucleic acids encoding any of the variant Fc regions described herein.
  • the present invention provides host cells comprising a nucleic acid encoding any of the variant Fc regions described herein.
  • the present invention provides methods of administering an antibody to a subject, where the antibody comprises a variant Fc region as compared to a parent Fc region, wherein the variant Fc region comprises a first mutation which is a serine at position 434 and a second mutation selected from the group: an isoleucine at position 311, a valine at position 311, an isoleucine at position 436, and a valine at position 436, where the antibody has increased serum half-life as compared to an antibody comprising the parent Fc region, and wherein numbering is according to the EU index.
  • FIG. 1 Sequence alignments of human IgG constant heavy chains. Gray indicates differences from IgG1, and boxed residues indicate common allotypic variations in the human population.
  • FIG. 2 (SEQ ID NO: 1-6) Amino acid sequences of constant regions used in the invention.
  • FIG. 3 (SEQ ID NO: 7-8) Amino acid sequences of exemplary variant constant regions.
  • FIG. 4 (SEQ ID NO: 9-1010) Amino acid sequences of VH and VL variable regions used in the invention.
  • FIG. 5 Relative VEGF binding by WT and select variant IgG1 anti-VEGF antibodies.
  • the plot shows the Biacore response units (RU) at the end of the association phase for binding of antibody analyte to immobilized VEGF antigen.
  • Anti-Her2 IgG1 antibody was used as a negative control.
  • FIG. 6 Biacore sensorgrams of WT and variant IgG1 antibodies to immobilized human FcRn at low (6.0) and high (7.4) pH.
  • FIG. 7 FcRn binding affinities of WT and select variant IgG1 antibodies to human FcRn at pH 6.0 as determined by Biacore.
  • the graph shows a plot of the pseudo-affinity constant (Ka*), on a log scale.
  • FIG. 8 a - 8 b In vivo pharmacokinetics of WT and variant antibodies in mFcRn ⁇ / ⁇ hFcRn+ mice. The graphs plot the serum concentration of antibody versus time after a single intravenous dose.
  • FIG. 8 a shows data from one of the 4 studies carried out with IgG1 antibodies (Study 3), and FIG. 8 b shows data from a study carried out with IgG2 antibodies (Study 5).
  • FIG. 9 Fitted PK parameters from all in vivo PK studies carried out in mFcRn ⁇ / ⁇ hFcRn + mice with variant and WT antibodies, n represents the number of mice per group, with Mean and standard deviation (SD) data provided for PK parameters.
  • Half-Life represents the beta phase that characterizes elimination of antibody from serum.
  • Cmax is the maximal observed serum concentration
  • AUG is the area under the concetration time curve
  • clearance is the clearance of antibody from serum.
  • Fold half-life is calculated as the half-life of variant antibody over that of the WT IgG1 or IgG2 parent within each study.
  • FIG. 10 a - 10 b Relative binding of variant IgG1 anti-VEGF antibodies to cynomolgus monkey and human FcRn as determined by Biacore.
  • FIG. 10 a shows the data in tabular form.
  • FIG. 10 b shows a plot of the data.
  • FIG. 11 In vivo pharmacokinetics of WT and variant antibodies in cynomolgus monkeys. The graphs plot the serum concentration of antibody versus time after a single intravenous dose.
  • FIG. 12 Fitted PK parameters from the in vivo PK study in cynomolgus monkeys with variant and WT antibodies. Parameters are as described in FIG. 9 .
  • FIG. 13 Designed Fc variants. Variants are screened using the described methods in order to obtain modifications that extend the in vivo half-life of antibodies.
  • FIG. 14 Screen of engineered Fc variants for binding to human FcRn.
  • the table shows the off-rate (k off ) for binding of each variant to human FcRn at pH 6.0 by Biacore.
  • FIG. 15 Graph of k off for screened Fc variants (data plotted are from FIG. 14 ).
  • FIG. 16 Affinities of select variants for human FcRn at pH 6.0 based on a FcRn concentration series Biacore experiment. The data show the on and off kinetic rate constants (k on and k off respectively), and the association and dissociation equilibrium constants (K A and K D respectively), as well as the fold improvement in K D and k off relative to WT IgG1 and IgG1/2N434S.
  • FIG. 17 Plot off affinities of select variants for human FcRn at pH 6.0 as determined by Biacore. Values are plotted from FIG. 16 .
  • FIG. 18 Plot off affinities of select variants for human FcRn at pH 6.0 as determined by Biacore. Values are plotted from FIG. 16 .
  • FIG. 19 Designed single variants
  • FIG. 20 Designed combination variants
  • FIG. 21 Affinities of select variants for human FcRn at pH 6.0 based on a FcRn concentration series Biacore experiment. The data show the dissociation equilibrium constant KD, as well as the fold improvement in KD relative to the IgG1/2 parent.
  • FIG. 22 Plot off affinities of select variants for human FcRn at pH 6.0 as determined by Biacore. Values are plotted from FIG. 21 .
  • FIG. 23 In vivo pharmacokinetics of IgG1/2 variant antibodies in mFcRn ⁇ / ⁇ hFcRn+ mice. The graphs plot the serum concentration of antibody versus time after a single intravenous dose.
  • FIG. 25 Scatter plot of half-life results from PK study in hFcRn + mice. Data are plotted from FIG. 24 . Each dot represents the t1 ⁇ 2 of an individual mouse within each variant group, and the line indicates the average.
  • the present invention discloses the generation of novel variants of Fc domains, including those found in antibodies, Fc fusions, and immuno-adhesions, which have an increased binding to the FcRn receptor. As noted herein, binding to FcRn results in longer serum retention in vivo.
  • Fc variants are also referred to herein as “Fc variants” or “FcRn variants”.
  • Fc substitutions are chosen such that the resultant proteins (“Fc proteins”) show improved serum half-life in vivo as compared to the wild type protein.
  • Fc proteins resultant proteins
  • the increase in binding affinity must be at around pH 6 while maintaining lower affinity at around pH 7.4.
  • Fc regions are believed to have longer half-lives in vivo, because binding to FcRn at pH 6 in an endosome sequesters the Fc (Ghetie and Ward, 1997 Immunol Today. 18(12): 592-598, entirely incorporated by reference).
  • the endosomal compartment then recycles the Fc to the cell surface.
  • An additional aspect of the invention is the increase in FcRn binding over wild type specifically at lower pH, about pH 6.0, to facilitate Fc/FcRn binding in the endosome.
  • Fc variants with altered FcRn binding and altered binding to another class of Fc receptors the Fc ⁇ R's (sometimes written FcgammaR's) as differential binding to Fc ⁇ Rs, particularly increased binding to Fc ⁇ RIIIb and decreased binding to Fc ⁇ RIIb, has been shown to result in increased efficacy.
  • IgG1 is a common isotype for therapeutic antibodies for a variety of reasons, including high effector function.
  • IgG2 residues at particular positions can be introduced into the IgG1 backbone to result in a protein that exhibits longer serum half-life.
  • non-isotypic amino acid changes are made, to improve binding to FcRn and/or to increase in vivo serum halt-life, and/or to allow accommodations in structure for stability, etc. as is more further described below.
  • the present invention demonstrates that while the absolute half life of two different antibodies may differ due to these antigen specificity effects, the FcRn variants described herein, can transfer to different ligands to give the same trends of increasing half-life. That is, in general, the relative “order” of the FcRn binding/half life increases will track to antibodies with the same variants of antibodies with different Fvs as is discussed herein.
  • the present invention relates to the generation of Fc variants of antibodies, generally therapeutic antibodies.
  • antibody is used generally. Antibodies that find use in the present invention can take on a number of formats as described herein, including traditional antibodies as well as antibody derivatives, fragments and mimetics, described below.
  • antibody includes any polypeptide that includes at least one constant domain, including, but not limited to, CH1, CH2, CH3 and CL.
  • Traditional antibody structural units typically comprise a tetramer. Each tetramer is typically composed of two identical pairs of polypeptide chains, each pair having one “light” (typically having a molecular weight of about 25 kDa) and one “heavy” chain (typically having a molecular weight of about 50-70 kDa). Human light chains are classified as kappa and lambda light chains.
  • the present invention is directed to the IgG class, which has several subclasses, including, but not limited to IgG1, IgG2, IgG3, and IgG4.
  • “isotype” as used herein is meant any of the subclasses of immunoglobulins defined by the chemical and antigenic characteristics of their constant regions.
  • therapeutic antibodies can also comprise hybrids of isotypes and/or subclasses. For example, as shown herein, the present invention covers Fc variant engineering of IgG1/G2 hybrids.
  • each chain includes a variable region of about 100 to 110 or more amino acids primarily responsible for antigen recognition, generally referred to in the art and herein as the “Fv domain” or “Fv region”.
  • Fv domain or “Fv region”.
  • CDR complementarity-determining region
  • Variable refers to the fact that certain segments of the variable region differ extensively in sequence among antibodies. Variability within the variable region is not evenly distributed. Instead, the V regions consist of relatively invariant stretches called framework regions (FRs) of 15-30 amino acids separated by shorter regions of extreme variability called “hypervariable regions” that are each 9-15 amino acids long or longer.
  • Each VH and VL is composed of three hypervariable regions (“complementary determining regions,” “CDRs”) and four FRs, arranged from amino-terminus to carboxy-terminus in the following order: FR1-CDR1-FR2-CDR2-FR3-CDR3-FR4.
  • the hypervariable region generally encompasses amino acid residues from about amino acid residues 24-34 (LCDR1; “L” denotes light chain), 50-56 (LCDR2) and 89-97 (LCDR3) in the light chain variable region and around about 31-35B (HCDR1; “H” denotes heavy chain), 50-65 (HCDR2), and 95-102 (HCDR3) in the heavy chain variable region; Kabat et al., SEQUENCES OF PROTEINS OF IMMUNOLOGICAL INTEREST, 5 th Ed. Public Health Service, National Institutes of Health, Bethesda, Md. (1991) and/or those residues forming a hypervariable loop (e.g.
  • the Kabat numbering system is generally used when referring to a residue in the variable domain (approximately, residues 1-107 of the light chain variable region and residues 1-113 of the heavy chain variable region) (e.g, Kabat et al., supra (199.1)).
  • epitope binding site contributes to the formation of the antigen-binding, or more specifically, epitope binding site of antibodies.
  • Epitope refers to a determinant that interacts with a specific antigen binding site in the variable region of an antibody molecule known as a paratope. Epitopes are groupings of molecules such as amino acids or sugar side chains and usually have specific structural characteristics, as well as specific charge characteristics. A single antigen may have more than one epitope.
  • the epitope may comprise amino acid residues directly involved in the binding (also called immunodominant component of the epitope) and other amino acid residues, which are not directly involved in the binding, such as amino acid residues which are effectively blocked by the specifically antigen binding peptide; in other words, the amino acid residue is within the footprint of the specifically antigen binding peptide.
  • Epitopes may be either conformational or linear.
  • a conformational epitope is produced by spatially juxtaposed amino acids from different segments of the linear polypeptide chain.
  • a linear epitope is one produced by adjacent amino acid residues in a polypeptide chain. Conformational and nonconformational epitopes may be distinguished in that the binding to the former but not the latter is lost in the presence of denaturing solvents.
  • An epitope typically includes at least 3, and more usually, at least 5 or 8-10 amino acids in a unique spatial conformation. Antibodies that recognize the same epitope can be verified in a simple immunoassay showing the ability of one antibody to block the binding of another antibody to a target antigen, for example “binning.”
  • any antigen may be targeted by the IgG variants, including but not limited to proteins, subunits, domains, motifs, and/or epitopes belonging to the following list of target antigens, which includes both soluble factors such as cytokines and membrane-bound factors, including transmembrane receptors: 17-IA, 4-1BB, 4Dc, 6-keto-PGF1a, 8-iso-PGF2a, 8-oxo-dG, A1 Adenosine Receptor, A33, ACE, ACE-2, Activin, Activin A, Activin AB, Activin B, Activin C, Activin RIA, Activin RIA ALK-2, Activin RIB ALK-4, Activin RIIA, Activin RIIB, ADAM, ADAM10, ADAM12,
  • CD5 CCL5, CCL6, CCL7, CCL8. CCL9/10, CCR, CCR1, CCR10, CCR10, CCR2, CCR3, CCR4, CCR5, CCR6, CCR7, CCR8, CCR9, CD1, CD2, CD3, CD3E, CD4, CD5, CD6, CD7, CD8, CD10, CD11a, CD11b, CD11c, CD13 CD14, CD15, CD16, CD18, CD19, CD20, CD21, CD22, CD23, CD25, CD27L, CD28, CD29, CD30, CD30L, CD32, CD33 (p67 proteins), CD34, CD38, CD40, CD40L, CD44, CD45, CD46, CD49a, CD52, CD54, CD55, CD56, CD61, CD64, CD66e, CD74, CD80 (B7-1), CD89, CD95, CD123, CD137, CD138, CD140a, CD146, CD147, CD148, CD152, CD164, CEACAM5, CF
  • the engineering of Fc domains described herein is done to therapeutic antibodies.
  • a number of antibodies that are approved for use, in clinical trials, or in development may benefit from the Fc variants of the present invention. These antibodies are herein referred to as “clinical products and candidates”.
  • the engineered constant region(s) of the present invention may find use in a range of clinical products and candidates.
  • a number of antibodies that target CD20 may benefit from the Fc engineering of the present invention.
  • the Fc variants of the present invention may find use in an antibody that is substantially similar to rituximab (Rituxan®, IDEC/Genentech/Roche) (see for example U.S. Pat. No.
  • a number of antibodies that target members of the family of epidermal growth factor receptors may benefit from Fc engineered constant region(s) of the invention.
  • the Fc engineered constant region(s) of the invention may find use in an antibody that is substantially similar to trastuzumab (Herceptin®, Genentech) (see for example U.S. Pat. No. 5,677,171), a humanized anti-Her2/neu antibody approved to treat breast cancer; pertuzumab (rhuMab-2C4, OmnitargTM), currently being developed by Genentech; an anti-Her2 antibody described in U.S. Pat. No.
  • cetuximab Erbitux®, Imclone
  • cetuximab Erbitux®, Imclone
  • PCT WO 96/40210 PCT WO 96/40210
  • ABX-EGF U.S. Pat. No. 6,235,883
  • HuMax-EGFr U.S. Ser. No. 10/172,317
  • Genmab 425, EMD55900, EMD62000, and EMD72000 (Merck KGaA) (U.S. Pat. No. 5,558,864; Murthy et al.
  • the Fc engineered constant region(s) of the present invention may find use in alemruzumab (Campath®, Millenium), a humanized monoclonal antibody currently approved for treatment of B-cell chronic lymphocytic leukemia.
  • the Fc engineered constant region(s) of the present invention may find use in a variety of antibodies that are substantially similar to other clinical products and candidates, including but not limited to muromonab-CD3 (Orthoclone OKT3®), an anti-CD3 antibody developed by Ortho Biotech/Johnson & Johnson, ibritumomab tiuxetan (Zevalin®), an anti-CD20 antibody developed by IDEC/Schering AG, gemtuzumab ozogamicin (Mylotarg®), an anti-CD33 (p67 protein) antibody developed by Celltech/Wyeth, alefacept (Amevive®), an anti-LFA-3 Fc fusion developed by Biogen), abciximab (ReoPro®), developed by Centocor/Lilly, basiliximab (Simulect®), developed by Novartis, palivizumab (Synagis®), developed by MedImmune, infliximab (Remicade®), an anti-
  • each chain defines a constant region primarily responsible for effector function.
  • Kabat et al. collected numerous primary sequences of the variable regions of heavy chains and light chains. Based on the degree of conservation of the sequences, they classified individual primary sequences into the CDR and the framework and made a list thereof (see SEQUENCES OF IMMUNOLOGICAL INTEREST, 5th edition, NIH publication, No. 91-3242, E. A. Kabat et al., entirely incorporated by reference).
  • immunoglobulin domains in the heavy chain.
  • immunoglobulin (Ig) domain herein is meant a region of an immunoglobulin having a distinct tertiary structure.
  • the heavy chain domains including, the constant heavy (CH) domains and the hinge domains.
  • the IgG isotypes each have three CH regions. Accordingly, “CH” domains in the context of IgG are as follows: “CH1” refers to positions 118-220 according to the EU index as in Kabat.
  • CH2 refers to positions 237-340 according to the EU index as in Kabat
  • CH3 refers to positions 341-447 according to the EU index as in Kabat.
  • the variants of the present invention can include substitutions in one or more of the CH regions, as well as the hinge region, discussed below.
  • sequences depicted herein start at the CH1 region, position 118; the variable regions are not included except as noted.
  • the first amino acid of SEQ ID NO: 2 while designated as position “1” in the sequence listing, corresponds to position 118 of the CH1 region, according to EU numbering.
  • Ig domain of the heavy chain is the hinge region.
  • hinge region or “hinge region” or “antibody hinge region” or “immunoglobulin hinge region” herein is meant the flexible polypeptide comprising the amino acids between the first and second constant domains of an antibody.
  • the IgG CH1 domain ends at EU position 220, and the IgG CH2 domain begins at residue EU position 237.
  • the antibody hinge is herein defined to include positions 221 (D221 in IgG1) to 236 (G236 in IgG1), wherein the numbering is according to the EU index as in Kabat.
  • the lower hinge is included, with the “lower hinge” generally referring to positions 226 or 230.
  • Fc variant variants can be made in the hinge region as well.
  • the light chain generally comprises two domains, the variable light domain (containing the light chain CDRs and together with the variable heavy domains forming the Fv region), and a constant light chain region (often referred to as CL or C ⁇ ).
  • Fc region Another region of interest for additional substitutions, outlined below, is the Fc region.
  • Fc region By “Fc” or “Fc region” or “Fc domain” as used herein is meant the polypeptide comprising the constant region of an antibody excluding the first constant region immunoglobulin domain and in some cases, part of the hinge.
  • Fc refers to the last two constant region immunoglobulin domains of IgA, IgD, and IgG, the last three constant region immunoglobulin domains of IgE and IgM, and the flexible hinge N-terminal to these domains.
  • Fc may include the J chain.
  • the Fc domain comprises immunoglobulin domains C ⁇ 2 and C ⁇ 3 (C ⁇ 2 and C ⁇ 3) and the lower hinge region between C ⁇ 1 (C ⁇ 1) and C ⁇ 2 (C ⁇ 2).
  • the human IgG heavy chain Fc region is usually defined to include residues C226 or P230 to its carboxyl-terminus, wherein the numbering is according to the EU index as in Kabat.
  • amino acid modifications are made to the Fc region, for example to alter binding to one or more Fc ⁇ R receptors or to the FcRn receptor.
  • the antibodies are full length.
  • full length antibody herein is meant the structure that constitutes the natural biological form of an antibody, including variable and constant regions, including one or more modifications as outlined herein.
  • the antibodies can be a variety of structures, including, but not limited to, antibody fragments, monoclonal antibodies, bispecific antibodies, minibodies, domain antibodies, synthetic antibodies (sometimes referred to herein as “antibody mimetics”), chimeric antibodies, humanized antibodies, antibody fusions (sometimes referred to as “antibody conjugates”), and fragments of each, respectively.
  • antibody mimetics sometimes referred to herein as “antibody mimetics”
  • chimeric antibodies humanized antibodies
  • antibody fusions sometimes referred to as “antibody conjugates”
  • the antibody is an antibody fragment, as long as it contains at least one constant domain which can be engineered.
  • Specific antibody fragments include, but are not limited to, (i) the Fab fragment consisting of VL, VH, CL and CH1 domains, (ii) the Fd fragment consisting of the VH and CH1 domains, (iii) F(ab′)2 fragments, a bivalent fragment comprising two linked Fab fragments (vii) single chain Fv molecules (scFv), wherein a.
  • VH domain and a VL domain are linked by a peptide linker which allows the two domains to associate to form an antigen binding site
  • a peptide linker which allows the two domains to associate to form an antigen binding site
  • antibody fragments that can be used include fragments that contain one or more of the CH1, CH2, CH3, hinge and CL domains of the invention that have been engineered.
  • Fc fusions are fusions of the Fc region (CH2 and CH3, optionally with the hinge region) fused to another protein.
  • a number of Fc fusions are known the art and can be improved by the addition of the variants of the invention.
  • antibody fusions can be made comprising CH1; CH1, CH2 and CH3; CH2; CH3; CH2 and CH3; CH1 and CH3, any or all of which can be made optionally with the hinge region, utilizing any combination of Fc variants described herein.
  • the antibody can be a mixture from different species, e.g. a chimeric antibody and/or a humanized antibody.
  • chimeric antibodies and “humanized antibodies” refer to antibodies that combine regions from more than one species.
  • chimeric antibodies traditionally comprise variable region(s) from a mouse (or rat, in some cases) and the constant region(s) from a human.
  • Humanized antibodies generally refer to non-human antibodies that have had the variable-domain framework regions swapped for sequences found in human antibodies.
  • the entire antibody, except the CDRs is encoded by a polynucleotide of human origin or is identical to such an antibody except within its CDRs.
  • the CDRs are grafted into the beta-sheet framework of a human antibody variable region to create an antibody, the specificity of which is determined by the engrafted CDRs.
  • the creation of such antibodies is described in, e.g., WO 92/11018, Jones, 1986, Nature 321:522-525, Verhoeyen et al., 1988, Science 239:1534-1536, all entirely incorporated by reference. “Backmutation” of selected acceptor framework residues to the corresponding donor residues is often required to regain affinity that is lost in the initial grafted construct (U.S. Pat. No. 5,530,101; U.S. Pat. No.
  • the humanized antibody optimally also will comprise at least a portion of an immunoglobulin constant region, typically that of a human immunoglobulin, and thus will typically comprise a human Fc region.
  • Humanized antibodies can also be generated using mice with a genetically engineered immune system, Roque et al., 2004, Biotechnol.
  • the parent antibody has been affinity matured, as is known in the art.
  • Structure-based methods may be employed for humanization and affinity maturation, for example as described in U.S. Ser. No. 11/004,590.
  • Selection based methods may be employed to humanize and/or affinity mature antibody variable regions, including but not limited to methods described in Wu et al., 1999, J. Mol. Biol. 294:151-162; Baca et al., 1997, J. Biol. Chem. 272(16): 10678-10684; Rosok et al., 1996, J. Biol. Chem. 271(37): 22611-22618; Rader et al., 1998, Proc. Natl. Acad. Sci.
  • the antibodies of the invention can be multispecific antibodies, and notably bispecific antibodies, also sometimes referred to as “diabodies”. These are antibodies that bind to two (or more) different antigens, or different epitopes on the same antigen. Diabodies can be manufactured in a variety of ways known in the art (Holliger and Winter, 1993, Current Opinion Biotechnol. 4:446-449, entirely incorporated by reference), e.g., prepared chemically or from hybrid hybridomas. In some cases, multispecific (for example bispecific) antibodies are not preferred.
  • the antibody is a minibody.
  • Minibodies are minimized antibody-like proteins comprising a scFv joined to a CH3 domain.
  • the CH3 domain can be engineered to improve binding to FcRn and/or increase in vivo serum half-life.
  • the scFv can be joined to the Fc region, and may include some or the entire hinge region.
  • 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.
  • 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.
  • 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 10 ⁇ 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.
  • 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.
  • 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.
  • Fc or “Fc region” or “Fc domain” as used herein is meant the polypeptide comprising the constant region of an antibody excluding the first constant region immunoglobulin domain and in some cases, part of the hinge.
  • Fc refers to the last two constant region immunoglobulin domains of IgA, IgD, and IgG, the last three constant region immunoglobulin domains of IgE and IgM, and the flexible hinge N-terminal to these domains.
  • Fc may include the J chain.
  • the Fc domain comprises immunoglobulin domains C ⁇ 2 and C ⁇ 3 (C ⁇ 2 and C ⁇ 3) and the lower hinge region between C ⁇ 1 (C ⁇ 1) and C ⁇ 2 (C ⁇ 2).
  • the human IgG heavy chain Fc region is usually defined to include residues C226 or P230 to its carboxyl-terminus, wherein the numbering is according to the EU index as in Kabat.
  • amino acid modifications are made to the Fc region, for example to alter binding to one or more Fc ⁇ R receptors or to the FcRn receptor.
  • Fc variants are made by introducing amino acid mutations into the parent molecule. “Mutations” in this context are usually amino acid substitutions, although as shown herein, deletions and insertions of amino acids can also be done and thus are defined as mutations.
  • FcRn or “neonatal Fc Receptor” as used herein is meant a protein that binds the IgG antibody Fc region and is encoded at least in part by an FcRn gene.
  • the FcRn may be from any organism, including but not limited to humans, mice, rats, rabbits, and monkeys.
  • the functional FcRn protein comprises two polypeptides, often referred to as the heavy chain and light chain.
  • the light chain is beta-2-microglobulin and the heavy chain is encoded by the FcRn gene.
  • FcRn or an FcRn protein refers to the complex of FcRn heavy chain with beta-2-microglobulin.
  • the FcRn variants bind to the human FcRn receptor, or it may be desirable to design variants that bind to rodent or primate receptors in addition, to facilitate clinical trials.
  • an Fc variant antibody can be engineered to include any of the following substitutions, alone or in any combination; 436I, 436V, 311I, 311V, 428L, 434S, 428L/434S, 259I, 308F, 259I/308F, 259I/308F/428L, 307Q/434S, 434A, 434H, 250Q/428L, M252Y/S254T/T256E, 307Q/434A, 307Q//380A/434A, and 308P/434A, 311I/434S, 311V/434S, 434S/436I, 434S/436V.
  • an Fc variant antibody can be engineered to include any of the following substitutions, alone or in any combination: 248Y, 249G, 253H, 253N, 253L, 253T, 253V, 253Q, 253M, 253Y, 253F, 253W, 255H, 255I, 255Q, 255E, 255F, 255L, 255S, 255G, 255W, 255P, 284D, 284E, 285D, 285E, 286Q, 286F, 286D, 286E, 286G, 286L, 286P, 286Y, 286W, 2861, 286V, 286R, 286K, 286H, 288N, 288H, 288Q, 288Y, 288F, 288W, 288L, 288I, 307M, 307E, 307R, 307D, 307G, 3071, 307N, 307P, 307Q,
  • the Fc variant of the invention includes at least two modifications, wherein one of said modifications is the substitution N434S, and the other of said modifications is a substitution selected from one or more of the following: 248Y, 249G, 253H, 253N, 253L, 253T, 253V, 253Q, 253M, 253Y, 253F, 253W, 255H, 255I, 255Q, 255E, 255F, 255L, 255S, 255G, 255W, 255P, 284D, 284E, 285D, 285E, 286Q, 286F, 286D, 286E, 286G, 286L, 286P, 286Y, 286W, 286I, 286V, 286R, 286K, 286H, 288N, 288H, 288Q, 288Y, 288F, 288W, 288L, 288I, 307M, 307E, 307R, 307R,
  • an Fc variant antibody can be engineered to include any of the following substitutions, alone or in any combination: 378T, 378E, 378I, 378L, 378M, 426G, 426A, 426Q, 426P, 426K, and 426R, where the numbering is according to the EU Index as in Kabat, and it is understood that the substitution is non-native to the starting molecule.
  • these FcRn substitutions work in IgG1, IgG2 and IgG1/G2 hybrid backbones, and are specifically included for IgG3 and IgG4 backbones and derivatives of any IgG isoform as well.
  • an Fc variant antibody can be engineered to include any of the substitutions in any of the following positions alone or in any combination: 307, 311, 378, 426, 428, 434, and 4.36.
  • the substitutions are as follows, again alone or in any combination: 307Q, 308P, 311I, 311V, 378E, 378F, 3781, 378L, 378M, 378R, 378T, 378V, 378Y, 426A, 426G, 426K, 426L, 426P, 426Q, 426R, 426V, 428L, 434S, 436I, and 436V.
  • the Fc variant antibody is engineered to include any of the of the following substitutions, alone or in any combination of the following or with any other of the substitutions discussed herein: T307Q/N434S/Q311I, T307Q/N434S/Q311V, T307Q/N434S/A378V, T307Q/N434S/S426V, T307Q/N434S/Y436I, T307Q/N434S/Y436V, T307Q/N434S/Y436V, Q311I/N434S/A378V, Q311I/N434S/A378T, Q311I/N434S/A378I, Q311I/N434S/A378L, Q311I/N434S/S426V, Q311I/N434S/Y436L Q311I/N434S/Y436V, Q311V/S
  • an Fc variant antibody can be engineered to include at least two of the following substitutions, alone or in any combination: 248Y, 249G, 253H, 253N, 253L, 253T, 253V, 253Q, 253M, 253Y, 253F, 253W, 255H, 255I, 255Q, 255E, 255F, 255L, 255S, 255G, 255W, 255P, 284D, 284E, 285D, 285E, 286Q, 286F, 286D, 286E, 286G, 286L, 286P, 286Y, 286W, 286I, 286V, 286R, 286K, 286H, 288N, 288H, 288Q, 288Y, 288F, 288W, 288L, 288I, 307M, 307E, 307R, 307D, 307G, 307I, 307N, 307P,
  • variable region(s) of the antibodies In other embodiments, no Fc variants are made in the variable region(s) of the antibodies. This is to be distinguished from affinity maturation substitutions in the variable region(s) that are made to increase binding affinity of the antibody to its antigen. That is, an Fc variant in the variable region(s) is generally significantly “silent” with respect to binding affinity.
  • the Fc variant antibodies of the invention can contain additional amino acid substitutions in addition to the substitutions discussed above.
  • amino acid substitutions are imported from one isotype into the Fc variant antibody.
  • a mutation at position 384 can be made, for example substituting a non-native serine.
  • Additional mutations that can be made include adding either N-terminal or C-terminal (depending on the structure of the antibody or fusion protein) “tails” or sequences of one or more Fc amino acids; for example, glutamic acids and aspartic acids can be added to the CH3 O-terminus; generally, from 1 to 5 amino acids are added.
  • the Fc variant antibodies of the invention display increased binding to FcRn and/or increased in vivo serum half-life.
  • some variants herein are generated to increase stability.
  • a number of properties of antibodies affect the clearance rate (e.g. stability for half-life) in vivo.
  • other factors that contribute to clearance and half-life are serum aggregation, enzymatic degradation in the serum, inherent immunogenicity of the antibody leading to clearing by the immune system, antigen-mediated uptake, FcR (non-FcRn) mediated uptake and non-serum distribution (e.g. in different tissue compartments).
  • substitutions made to increase binding affinity to FcRn and/or increase serum half life other substitutions can be made in the Fc region, in general for altering binding to Fc ⁇ R receptors.
  • Fc gamma receptor any member of the family of proteins that bind the IgG antibody Fc region and is encoded by an Fc ⁇ R gene. In humans this family includes but is not limited to Fc ⁇ RI (CD64), including isoforms Fc ⁇ RIa, Fc ⁇ RIb, and Fc ⁇ RIc; Fc ⁇ RII (CD32), including isoforms Fc ⁇ RIIa (including allotypes H131 and R131), Fc ⁇ RIIb (including Fc ⁇ RIIb-1 and Fc ⁇ RIIb-2), and Fc ⁇ RIIc; and Fc ⁇ RIII (CD16), including isoforms Fc ⁇ RIIIa (including allotypes V158 and F158) and Fc ⁇ RIIIb (including allotypes Fc ⁇ RIIIb-NA1 and Fc ⁇ RIIIb-NA2) (Jefferis et al., 2002 , Immunol Lett 82:57-
  • An Fc ⁇ R may be from any organism, including but not limited to humans, mice, rats, rabbits, and monkeys.
  • Mouse Fc ⁇ Rs include but are not limited to Fc ⁇ RI (CD64), Fc ⁇ RII (CD32), Fc ⁇ RIII-1 (CD16), and Fc ⁇ RIII-2 (CD16-2), as well as any undiscovered mouse Fc ⁇ Rs or Fc ⁇ R isoforms or allotypes.
  • Fc substitutions that can be made to alter binding to one or more of the Fc ⁇ R receptors.
  • Substitutions that result in increased binding as well as decreased binding can be useful.
  • ADCC antibody dependent cell-mediated cytotoxicity; the cell-mediated reaction wherein nonspecific cytotoxic cells that express Fc ⁇ Rs recognize bound antibody on a target cell and subsequently cause lysis of the target cell.
  • Fc ⁇ RIIb an inhibitory receptor
  • Amino acid substitutions that find use in the present invention include those listed in U.S. Ser. No. 11/124,620 (particularly FIG. 41), U.S. Ser. Nos.
  • one or more amino acid modifications are made in one or more of the CDRs of the antibody.
  • 1 or 2 or 3-amino acids are substituted in any single CDR, and generally no more than from 4, 5, 6, 7, 8 9 or 10 changes are made within a set of CDRs.
  • any combination of no substitutions, 1, 2 or 3 substitutions in any CDR can be independently and optionally combined with any other substitution.
  • amino acid modifications in the CDRs are referred to as “affinity maturation”.
  • An “affinity matured” antibody is one having one or more alteration(s) in one or more CDRs which results in an improvement in the affinity of the antibody for antigen, compared to a parent antibody which does not possess those alteration(s).
  • Affinity maturation can be done to increase the binding affinity of the antibody for the antigen by at least about 10% to 50-100-150% or more, or from 1 to 5 fold as compared to the “parent” antibody.
  • Preferred affinity matured antibodies will have nanomolar or even picomolar affinities for the target antigen.
  • Affinity matured antibodies are produced by known procedures. See, for example, Marks et al., 1992, Biotechnology 10:779-783 that describes affinity maturation by variable heavy chain (VH) and variable light chain (VL) domain shuffling. Random mutagenesis of CDR and/or framework residues is described in: Barbas, et al. 1994, Proc. Nat, Acad.
  • amino acid modifications can be made in one or more of the CDRs of the antibodies of the invention that are “silent”, e.g. that do not significantly alter the affinity of the antibody for the antigen. These can be made for a number of reasons, including optimizing expression (as can be done for the nucleic acids encoding the antibodies of the invention).
  • variant CDRs and antibodies of the invention can include amino acid modifications in one or more of the CDRs of Ab79 and Ab19.
  • amino acid modifications can also independently and optionally be made in any region outside the CDRs, including framework and constant regions.
  • the Fc variant antibodies of the invention are conjugated with drugs to form antibody-drug conjugates (ADCs).
  • ADCs are used in oncology applications, where the use of antibody-drug conjugates for the local delivery of cytotoxic or cytostatic agents allows for the targeted delivery of the drug moiety to tumors, which can allow higher efficacy, lower toxicity, etc.
  • An overview of this technology is provided in Ducry et al., Bioconjugate Chem., 21:5-13 (2010), Carter et al., Cancer J. 14(3):154 (2008) and Senter, Current Opin. Chem. Biol. 13:235-244 (2009), all of which are hereby incorporated by reference in their entirety
  • the invention provides Fc variant antibodies conjugated to drugs.
  • conjugation is done by covalent attachment to the antibody, as further described below, and generally relies on a linker, often a peptide linkage (which, as described below, may be designed to be sensitive to cleavage by proteases at the target site or not).
  • linkage of the linker-drug unit (LU-D) can be done by attachment to cysteines within the antibody.
  • the number of drug moieties per antibody can change, depending on the conditions of the reaction, and can vary from 1:1 to 10:1 drug:antibody. As will be appreciated by those in the art, the actual number is an average.
  • the invention provides Fc variant antibodies conjugated to drugs.
  • the drug of the ADC can be any number of agents, including but not limited to cytotoxic agents such as chemotherapeutic agents, growth inhibitory agents, toxins (for example, an enzymatically active toxin of bacterial, fungal, plant, or animal origin, or fragments thereof), or a radioactive isotope (that is, a radioconjugate) are provided.
  • the invention further provides methods of using the ADCs.
  • Drugs for use in the present invention include cytotoxic drugs, particularly those which are used for cancer therapy.
  • Such drugs include, in general, DNA damaging agents, anti-metabolites, natural products and their analogs.
  • cytotoxic agents include the enzyme inhibitors such as dihydrofolate reductase inhibitors, and thymidylate synthase inhibitors, DNA intercalators, DNA cleavers, topoisomerase inhibitors, the anthracycline family of drugs, the vinca drugs, the mitomycins, the bleomycins, the cytotoxic nucleosides, the pteridine family of drugs, diynenes, the podophyllotoxins, dolastatins, maytansinoids, differentiation inducers, and taxols.
  • enzyme inhibitors such as dihydrofolate reductase inhibitors, and thymidylate synthase inhibitors, DNA intercalators, DNA cleavers, topoisomerase inhibitors, the anthracycline family of
  • Toxins may be used as antibody-toxin conjugates and include bacterial toxins such as diphtheria toxin, plant toxins such as ricin, small molecule toxins such as geldanamycin (Mandler et al (2000) J. Nat, Cancer Inst. 92(19): 1573-1581; Mandler et al (2000) Bioorganic & Med. Chem. Letters 10:1025-1028; Mandler et al (2002) Bioconjugate Chem. 13:786-791), maytansinoids (EP 1391213; Liu et al., (1996) Proc. Natl. Acad. Sci. USA 93:8618-862.3), and calicheamicin (Lode et al (1998) Cancer Res. 58:2928; Hinman et al (1993) Cancer Res. 53:3336-3342). Toxins may exert their cytotoxic and cytostatic effects by mechanisms including tubulin binding, DNA binding, or topoisomerase inhibition.
  • a maytansinoids such as a maytansinoids, dolastatins, auristatins, a trichothecene, calicheamicin, and CC1065, and the derivatives of these toxins that have toxin activity, are contemplated.
  • Maytansine compounds suitable for use as maytansinoid drug moieties are well known in the art, and can be isolated from natural sources according to known methods, produced using genetic engineering techniques (see Yu et al (2002) PNAS 99:7968-7973), or maytansinol and maytansinol analogues prepared synthetically according to known methods.
  • drugs may be modified by the incorporation of a functionally active group such as a thiol or amine group for conjugation to the antibody.
  • Exemplary maytansinoid drug moieties include those having a modified aromatic ring, such as: C-19-dechloro (U.S. Pat. No. 4,256,746) (prepared by lithium aluminum hydride reduction of ansamytocin P2); C-20-hydroxy (or C-20-demethyl)+/ ⁇ C-19-dechloro (U.S. Pat. Nos. 4,361,650 and 4,307,016) (prepared by demethylation using Streptomyces or Actinomyces or dechlorination using LAH); and C-20-demethoxy, C-20-acyloxy (—OCOR), +/ ⁇ dechloro (U.S. Pat. No. 4,294,757) (prepared by acylation using acyl chlorides) and those having modifications at other positions
  • Exemplary maytansinoid drag moieties also include those having modifications such as: C-9-SH (U.S. Pat. No. 4,424,219) (prepared by the reaction of maytansinol with H2S or P2S5); C-14-alkoxymethyl(demethoxy/CH2OR) (U.S. Pat. No. 4,331,598); C-14-hydroxymethyl or acyloxymethyl (CH2OH or CH2OAc) (U.S. Pat. No. 4,450,254) prepared from Nocardia ); C-15-hydroxy/acyloxy (U.S. Pat. No. 4,364,866) (prepared by the conversion of maytansinol by Streptomyces ); C-15-methoxy (U.S. Pat. Nos.
  • DM1 Dislosed in U.S. Pat. No. 5,208,020, incorporated by reference
  • DM4 Dislosed in U.S. Pat. No. 7,276,497, incorporated by reference
  • ADC's containing maytansinoids, methods of making same, and their therapeutic use are disclosed, for example, in U.S. Pat. Nos. 5,208,020; 5,416,064; 6,441,163 and European Patent EP 0 425 235 B1, the disclosures of which are hereby expressly incorporated by reference, Liu et al., Proc. Natl. Acad, Sci. USA 93:8618-8623 (1996) described ADCs comprising a maytansinoid designated DM1 linked to the monoclonal antibody C242 directed against human colorectal cancer. The conjugate was found to be highly cytotoxic towards cultured colon cancer cells, and showed antitumor activity in an in vivo tumor growth assay.
  • ADCs in which a maytansinoid was conjugated via a disulfide linker to the murine antibody A7 binding to an antigen on human colon cancer cell lines, or to another murine monoclonal antibody TA. 1 that binds the HER-2/neu oncogene.
  • the cytotoxicity of the TA.1-maytansonoid conjugate was tested in vitro on the human breast cancer cell line SK-BR-3, which expresses 3 ⁇ 105 HER-2 surface antigens per cell.
  • the drug conjugate achieved a degree of cytotoxicity similar to the free maytansinoid drug, which could be increased by increasing the number of maytansinoid molecules per antibody molecule.
  • the A7-maytansinoid conjugate showed low systemic cytotoxicity in mice.
  • the ADC comprises an Fc variant antibody conjugated to dolastatins or dolostatin peptidic analogs and derivatives, the auristatins (U.S. Pat. Nos. 5,635,483; 5,780,588).
  • Dolastatins and auristatins have been shown to interfere with microtubule dynamics, GTP hydrolysis, and nuclear and cellular division (Woyke et al (2001) Antimicrob. Agents and Chemother. 45(12):3580-3584) and have anticancer (U.S. Pat. No. 5,663,149) and antifungal activity (Pettit et al (1998) Antimicrob. Agents Chemother, 42:2961-2965).
  • the dolastatin or auristatin drug moiety may be attached to the antibody through the N (amino) terminus or the C (carboxyl) terminus of the peptidic drug moiety (WO 02/088172).
  • Exemplary auristatin embodiments include the N-terminus linked monomethylauristatin drug moieties DE and DF, disclosed in “Senter et al, Proceedings of the American Association for Cancer Research, Volume 45, Abstract Number 623, presented Mar. 28, 2004 and described in United States Patent Publication No. 2005/0238648, the disclosure of which is expressly incorporated by reference in its entirety.
  • An exemplary auristatin embodiment is MMAE (shown in FIG. 10 wherein the wavy line indicates the covalent attachment to a linker (L) of an antibody drug conjugate; see U.S. Pat. No. 6,884,869 expressly incorporated by reference in its entirety).
  • MMAF Another exemplary auristatin embodiment is MMAF, shown in FIG. 10 wherein the wavy line indicates the covalent attachment to a linker (L) of an antibody drag conjugate (US 2005/0238649, 5,767,237 and 6,124,431, expressly incorporated by reference in their entirety):
  • peptide-based drug moieties can be prepared by forming a peptide bond between two or more amino acids and/or peptide fragments.
  • Such peptide bonds can be prepared, for example, according to the liquid phase synthesis method (see E. Schroder and K. Lubke, “The Peptides”, volume 1, pp 76-136, 1965, Academic Press) that is well known in the field of peptide chemistry.
  • the auristatin/dolastatin drug moieties may be prepared according to the methods of: U.S. Pat. No. 5,635,483; U.S. Pat. No. 5,780,588; Pettit et al (1989) J. Am. Chem. Soc.
  • the ADC comprises an antibody of the invention conjugated to one or more calicheamicin molecules.
  • Mylotarg is the first commercial ADC drug and utilizes calicheamicin ⁇ 1 as the payload (see U.S. Pat. No. 4,970,198, incorporated by reference in its entirety). Additional calicheamicin derivatives are described in U.S. Pat. Nos. 5,264,586, 5,384,412, 5,550,246, 5,739,116, 5,773,001, 5,767,285 and 5,877,296, all expressly incorporated by reference.
  • the calicheamicin family of antibiotics are capable of producing double-stranded DNA breaks at sub-picomolar concentrations.
  • Another anti-tumor drug that the antibody can be conjugated is QFA which is an antifolate.
  • QFA an antifolate.
  • calicheamicin and QFA have intracellular sites of action and do not readily cross the plasma membrane. Therefore, cellular uptake of these agents through antibody mediated internalization greatly enhances their cytotoxic effects.
  • CC-1065 (see U.S. Pat. No. 4,169,888, incorporated by reference) and duocarmycins are members of a family of antitumor antibiotics utilized in ADCs. These antibiotics appear to work through sequence-selectively alkylating DNA at the N3 of adenine in the minor groove, which initiates a cascade of events that result in apoptosis.
  • duocarmycin A U.S. Pat. No. 4,923,990, incorporated by reference
  • duocarmycin SA U.S. Pat. No. 5,101,038, incorporated by reference
  • analogues as described in U.S. Pat. Nos.
  • Enzymatically active toxins and fragments thereof which can be used include diphtheria A chain, nonbinding active fragments of diphtheria toxin, exotoxin A chain (from Pseudomonas aeruginosa ), ricin A chain, abrin A chain, modeccin A chain, alpha-sarcin, Aleurites fordii proteins, dianthin proteins, Phytolaca americana proteins (PAPI, PAPII, and PAP-S), momordica charantia inhibitor, curcin, cretin, sapaonaria officinalis inhibitor, gelonin, mitogellin, restrictocin, phenomycin, enomycin and the tricothecenes. See, for example, WO 93/21232 published Oct. 28, 1993.
  • the present invention further contemplates an ADC formed between an antibody and a compound with nucleolytic activity (e.g., a ribonuclease or a DNA endonuclease such as a deoxyribonuclease; DNase).
  • a compound with nucleolytic activity e.g., a ribonuclease or a DNA endonuclease such as a deoxyribonuclease; DNase.
  • the antibody may comprise a highly radioactive atom.
  • radioactive isotopes are available for the production of radio-conjugated antibodies. Examples include At211, I131, I125, Y90, Re186, Re188, Sm153, Bi212, P32, Pb212 and radioactive isotopes of Lit.
  • the radio- or other labels may be incorporated in the conjugate in known ways.
  • the peptide may be biosynthesized or may be synthesized by chemical amino acid synthesis using suitable amino acid precursors involving, for example, fluorine-19 in place of hydrogen.
  • Labels such as Tc99m or I123, Re186, Re188 and In111 can be attached via a cysteine residue in the peptide, Yttrium-90 can be attached via a lysine residue.
  • the IODOGEN method (Fraker et al (1978) Biochem. Biophys. Res. Commun. 80: 49-57 can be used to incorporate Iodine-123. “Monoclonal Antibodies in Immunoscintigraphy” (Chatal, CRC Press 1989) describes other methods in detail.
  • the drug loading is represented by p, the average number of drag molecules per Antibody.
  • Drag loading may range from 1 to 20 drugs (D) per Antibody.
  • the average number of drags per antibody in preparation of conjugation reactions may be characterized by conventional means such as mass spectroscopy, ELISA assay, and HPLC.
  • the quantitative distribution of Antibody-Drug-Conjugates in terms of p may also be determined.
  • p is a certain value from Antibody-Drug-Conjugates with other drug loadings
  • separation, purification, and characterization of homogeneous Antibody-Drug-conjugates where p is a certain value from Antibody-Drug-Conjugates with other drug loadings may be achieved by means such as reverse phase HPLC or electrophoresis.
  • p is 2, 3, 4, 5, 6, 7, or 8 or a fraction thereof.
  • the generation of Antibody-drag conjugate compounds can be accomplished by any technique known to the skilled artisan.
  • the Antibody-drug conjugate compounds can include an Fc variant antibody as the Antibody unit, a drug, and optionally a linker that joins the drag and the binding agent.
  • a number of different reactions are available for covalent attachment of drags and/or linkers to binding agents. This is can be accomplished by reaction of the amino acid residues of the binding agent, for example, antibody molecule, including the amine groups of lysine, the free carboxylic acid groups of glutamic and aspartic acid, the sulfhydryl groups of cysteine and the various moieties of the aromatic amino acids.
  • a commonly used non-specific methods of covalent attachment is the carbodiimide reaction to link a carboxy (or amino) group of a compound to amino (or carboxy) groups of the antibody.
  • bifunctional agents such as dialdehydes or imidoesters have been used to link the amino group of a compound to amino groups of an antibody molecule.
  • Schiff base reaction also available for attachment of drugs to binding agents.
  • This method involves the periodate oxidation of a drug that contains glycol or hydroxy groups, thus forming an aldehyde which is then reacted with the binding agent. Attachment occurs via formation of a.
  • Schiff base with amino groups of the binding agent Isothiocyanates can also be used as coupling agents for covalently attaching drugs to binding agents. Other techniques are known to the skilled artisan and within the scope of the present invention.
  • an intermediate which is the precursor of the linker, is reacted with the drug under appropriate conditions.
  • reactive groups are used on the drug and/or the intermediate.
  • the product of the reaction between the drug and the intermediate, or the derivatized drag, is subsequently reacted with an Fc variant antibody of the invention under appropriate conditions.
  • the antibody-drag conjugate compounds comprise a Linker unit between the drug unit and the antibody unit.
  • the linker is cleavable under intracellular or extracellular conditions, such that cleavage of the linker releases the drug unit from the antibody in the appropriate environment.
  • solid tumors that secrete certain proteases may serve as the target of the cleavable linker; in other embodiments, it is the intracellular proteases that are utilized.
  • the linker unit is not cleavable and the drug is released, for example, by antibody degradation in lysosomes.
  • the linker is cleavable by a cleaving agent that is present in the intracellular environment (for example, within a lysosome or endosome or caveolea).
  • the linker can be, for example, a peptidyl linker that is cleaved by an intracellular peptidase or protease enzyme, including, but not limited to, a lysosomal or endosomal protease.
  • the peptidyl linker is at least two amino acids long or at least three amino acids long or more.
  • Cleaving agents can include, without limitation, cathepsins B and D and plasmin, all of which are known to hydrolyze dipeptide drug derivatives resulting in the release of active drug inside target cells (see, e.g., Dubowchik and Walker, 1999, Pharm. Therapeutics 83:67-123). Peptidyl linkers that are cleavable by enzymes that are present in CD38-expressing cells.
  • a peptidyl linker that is cleavable by the thiol-dependent protease cathepsin-B, which is highly expressed in cancerous tissue can be used (e.g., a Phe-Leu or a Gly-Phe-Leu-Gly linker (SEQ ID NO: 11).
  • Other examples of such linkers are described, e.g., in U.S. Pat. No. 6,214,345, incorporated herein by reference in its entirety and for all purposes.
  • the peptidyl linker cleavable by an intracellular protease is a Val-Cit linker or a Phe-Lys linker (see, e.g., U.S. Pat. No. 6,214,345, which describes the synthesis of doxorubicin with the val-cit linker).
  • the cleavable linker is pH-sensitive, that is, sensitive to hydrolysis at certain pH values.
  • the pH-sensitive linker hydrolyzable under acidic conditions.
  • an acid-labile linker that is hydrolyzable in the lysosome for example, a hydrazone, semicarbazone, thiosemicarbazone, cis-aconitic amide, orthoester, acetal, ketal, or the like
  • an acid-labile linker that is hydrolyzable in the lysosome for example, a hydrazone, semicarbazone, thiosemicarbazone, cis-aconitic amide, orthoester, acetal, ketal, or the like
  • the hydrolyzable linker is a thioether linker (such as, e.g., a thioether attached to the therapeutic agent via an acylhydrazone bond (see, e.g., U.S. Pat. No. 5,622,929).
  • the linker is cleavable under reducing conditions (for example, a disulfide linker).
  • a disulfide linker for example, a disulfide linker.
  • disulfide linkers are known in the art, including, for example, those that can be formed using SATA (N-succinimidyl-5-acetylthioacetate), SPDP (N-succinimidyl-3-(2-pyridyldithio)propionate), SPDB (N-succinimidyl-3-(2-pyridyldithio)butyrate) and SMPT (N-succinimidyl-oxycarbonyl-alpha-methyl-alpha-(2-pyridyl-dithio)toluene)-, SPDB and SMPT.
  • SATA N-succinimidyl-5-acetylthioacetate
  • SPDP N-succinimidyl-3-(2-pyri
  • the linker is a malonate linker (Johnson et al., 1995, Anticancer Res. 15:1387-93), a maleimidobenzoyl linker (Lau et al., 1995, Bioorg-Med-Chem. 3(10): 1299-1304), or a 3′-N-amide analog (Lau et al., 1995, Bioorg-Med-Chem. 3(10):1305-12).
  • the linker unit is not cleavable and the drug is released by antibody degradation.
  • the linker is self-immolative.
  • self-immolative Spacer refers to a bifunctional chemical moiety that is capable of covalently linking together two spaced chemical moieties into a stable tripartite molecule. It will spontaneously separate from the second chemical moiety if its bond to the first moiety is cleaved.
  • WO 2007059404A2, WO06110476A2, WO05112919A2, WO2010/062171, WO09/017,394, WO07/089,149, WO 07/018,431, WO04/043493 and WO02/083180 which are directed to drug-cleavable substrate conjugates where the drug and cleavable substrate are optionally linked through a self-immolative linker and which are all expressly incorporated by reference.
  • linker is not substantially sensitive to the extracellular environment.
  • “not substantially sensitive to the extracellular environment,” in the context of a linker means that no more than about 20%, 15%, 10%, 5%, 3%, or no more than about 1% of the linkers, in a sample of antibody-drag conjugate compound, are cleaved when the antibody-drug conjugate compound presents in an extracellular environment (for example, in plasma).
  • Whether a linker is not substantially sensitive to the extracellular environment can be determined, for example, by incubating with plasma the antibody-drug conjugate compound for a predetermined time period (for example, 2, 4, 8, 16, or 24 hours) and then quantitating the amount of free drug present in the plasma.
  • a predetermined time period for example, 2, 4, 8, 16, or 24 hours
  • the linker promotes cellular internalization. In certain embodiments, the linker promotes cellular internalization when conjugated to the therapeutic agent (that is, in the milieu of the linker-therapeutic agent moiety of the antibody-drug conjugate compound as described herein). In yet other embodiments, the linker promotes cellular internalization when conjugated to both the auristatin compound and the Fc variant antibodies of the invention.
  • Drag loading is represented by p and is the average number of Drag moieties per antibody in a molecule.
  • Drug loading (“p”) may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more moieties (D) per antibody, although frequently the average number is a fraction or a decimal. Generally, drug loading of from 1 to 4 is frequently useful, and from 1 to 2 is also useful.
  • ADCs of the invention include collections of antibodies conjugated with a range of drag moieties, from 1 to 20. The average number of drug moieties per antibody in preparations of ADC from conjugation reactions may be characterized by conventional means such as mass spectroscopy and, ELISA assay.
  • ADC quantitative distribution of ADC in terms of p may also be determined.
  • separation, purification, and characterization of homogeneous ADC where p is a certain value from ADC with other drug loadings may be achieved by means such as electrophoresis.
  • p may be limited by the number of attachment sites on the antibody.
  • the attachment is a cysteine thiol
  • an antibody may have only one or several cysteine thiol groups, or may have only one or several sufficiently reactive thiol groups through which a linker may be attached.
  • higher drug loading e.g. p>5
  • the drug loading for an ADC of the invention ranges from 1 to about 8; from about 2 to about 6; from about 3 to about 5; from about 3 to about 4; from about 3.1 to about 3.9; from about 3.2 to about 3.8; from about 3.2 to about 3.7; from about 3.2 to about 3.6; from about 3.3 to about 3.8; or from about 3.3 to about 3.7.
  • the optimal ratio of drug moieties per antibody may be less than 8, and may be about 2 to about 5. See US 2005-0238649 A1 (herein incorporated by reference in its entirety).
  • an antibody may contain, for example, lysine residues that do not react with the drug-linker intermediate or linker reagent, as discussed below. Generally, antibodies do not contain many free and reactive cysteine thiol groups which may be linked to a drug moiety; indeed most cysteine thiol residues in antibodies exist as disulfide bridges.
  • an antibody may be reduced with a reducing agent such as dithiothreitol (DTT) or tricarbonylethylphosphine (TCEP), under partial or total reducing conditions, to generate reactive cysteine thiol groups.
  • DTT dithiothreitol
  • TCEP tricarbonylethylphosphine
  • an antibody is subjected to denaturing conditions to reveal reactive nucleophilic groups such as lysine or cysteine.
  • the loading (drug/antibody ratio) of an ADC may be controlled in different ways, e.g., by: (i) limiting the molar excess of drug-linker intermediate or linker reagent relative to antibody, (ii) limiting the conjugation reaction time or temperature, (iii) partial or limiting reductive conditions for cysteine thiol modification, (iv) engineering by recombinant techniques the amino acid sequence of the antibody such that the number and position of cysteine residues is modified for control of the number and/or position of linker-drug attachments (such as thioMab or fhioFab prepared as disclosed herein and in WO2006/034488 (herein incorporated by reference in its entirety)).
  • linker-drug attachments such as thioMab or fhioFab prepared as disclosed herein and in WO2006/034488 (herein incorporated by reference in its entirety)).
  • the resulting product is a mixture of ADC compounds with a distribution of one or more drag moieties attached to an antibody.
  • the average number of drugs per antibody may be calculated from the mixture by a dual ELISA antibody assay, which is specific for antibody and specific for the drug.
  • Individual ADC molecules may be identified in the mixture by mass spectroscopy and separated by HPLC, e.g. hydrophobic interaction chromatography.
  • a homogeneous ADC with a single loading value may be isolated from the conjugation mixture by electrophoresis or chromatography.
  • cytotoxic or cytostatic activity of an Antibody Drag conjugate can be measured by: exposing mammalian cells expressing a target protein of the Antibody Drag conjugate in a cell culture medium; culturing the cells for a period from about 6 hours to about 5 days; and measuring cell viability.
  • Cell-based in vitro assays can be used to measure viability (proliferation), cytotoxicity, and induction of apoptosis (caspase activation) of the Antibody Drag conjugate.
  • a thymidine incorporation assay may be used. For example, cancer cells expressing a target antigen at a density of 5,000 cells/well of a 96-well plated can be cultured for a 72-hour period and exposed to 0.5 ⁇ Ci of 3 H-thymidine during the final 8 hours of the 72-hour period. The incorporation of 3 H-thymidine into cells of the culture is measured in the presence and absence of the Antibody Drug conjugate.
  • necrosis or apoptosis can be measured.
  • necrosis is typically accompanied by increased permeability of the plasma membrane; swelling of the cell, and rupture of the plasma membrane.
  • Apoptosis is typically characterized by membrane blebbing, condensation of cytoplasm, and the activation of endogenous endonucleases. Determination of any of these effects on cancer cells indicates that an Antibody Drug conjugate is useful in the treatment of cancers.
  • Cell viability can be measured by determining in a cell the uptake of a dye such as neutral red, trypan blue, or ALAMARTM blue (see, e.g., Page et al., 1993, Intl. J. Oncology 3:473-476).
  • a dye such as neutral red, trypan blue, or ALAMARTM blue
  • the cells are incubated in media containing the dye, the cells are washed, and the remaining dye, reflecting cellular uptake of the dye, is measured spectrophotometrically.
  • the protein-binding dye sulforhodamine B (SRB) can also be used to measure cytoxicity (Skehan et al., 1990, J. Natl Cancer Inst. 82:1107-12).
  • a tetrazolium salt such as MTT
  • MTT a tetrazolium salt
  • Apoptosis can be quantitated by measuring, for example, DNA fragmentation.
  • Commercial photometric methods for the quantitative in vitro determination of DNA fragmentation are available. Examples of such assays, including TUNEL (which detects incorporation of labeled nucleotides in fragmented DNA) and ELISA-based assays, are described in Biochemica, 1999, no. 2, pp. 34-37 (Roche Molecular Biochemicals).
  • Apoptosis can also be determined by measuring morphological changes in a cell. For example, as with necrosis, loss of plasma membrane integrity can be determined by measuring uptake of certain dyes (e.g., a fluorescent dye such as, for example, acridine orange or ethidium bromide).
  • a fluorescent dye such as, for example, acridine orange or ethidium bromide.
  • a method for measuring apoptotic cell number has been described by Duke and Cohen, Current Protocols in Immunology (Coligan et al. eds., 1992, pp. 3.17.1-3.17.16).
  • Cells also can be labeled with a DNA dye (e.g., acridine orange, ethidium bromide, or propidium iodide) and the cells observed for chromatin condensation and margination along the inner nuclear membrane.
  • Other morphological changes that can be measured to determine apoptosis include, e.g., cytoplasmic condensation
  • the presence of apoptotic cells can be measured in both the attached and “floating” compartments of the cultures.
  • both compartments can be collected by removing the supernatant, trypsinizing the attached cells, combining the preparations following a centrifugation wash step (e.g., 10 minutes at 2000 rpm), and detecting apoptosis (e.g., by measuring DNA fragmentation).
  • a centrifugation wash step e.g. 10 minutes at 2000 rpm
  • detecting apoptosis e.g., by measuring DNA fragmentation.
  • the effect of a therapeutic composition of the Fc variant antibody of the invention can be evaluated in a suitable animal model.
  • xenogenic cancer models can be used, wherein cancer explants or passaged xenograft tissues are introduced into immune compromised animals, such as nude or SCID mice (Klein et al., 1997, Nature Medicine 3: 402-408). Efficacy can be measured using assays that measure inhibition of tumor formation, tumor regression or metastasis, and the like.
  • Suitable carriers include any material that when combined with the therapeutic composition retains the anti-tumor function of the therapeutic composition and is generally non-reactive with the patient's immune system. Examples include, but are not limited to, any of a number of standard pharmaceutical carriers such as sterile phosphate buffered saline solutions, bacteriostatic water, and the like (see, generally, Remington's Pharmaceutical Sciences 16th Edition, A. Osal., Ed., 1980).
  • the antibodies disclosed herein can be modified to include one or more engineered glycoforms.
  • engineered glycoform as used herein is meant a carbohydrate composition that is covalently attached to the antibody, wherein said carbohydrate composition differs chemically from that of a parent antibody.
  • Engineered glycoforms may be useful for a variety of purposes, including but not limited to enhancing or reducing effector function.
  • a preferred form of engineered glycoform is afucosylation, which has been shown to be correlated to an increase in ADCC function, presumably through tighter binding to the Fc ⁇ RIIIa receptor.
  • afucosylation means that the majority of the antibody produced in the host cells is substantially devoid of fucose, e.g. 90-95-98% of the generated antibodies do not have appreciable fucose as a component of the carbohydrate moiety of the antibody (generally attached at N297 in the Fc region).
  • afucosylated antibodies generally exhibit at least a 50% or higher affinity to the Fc ⁇ RIIIa receptor.
  • Engineered glycoforms may be generated by a variety of methods known in the art (Uma ⁇ a et al., 1999, Nat Biotechnol 17:176-180; Davies et al., 2001, Biotechnol Bioeng 74:288-294; Shields et al., 2002, J Biol Chem 277:26733-26740; Shinkawa et al., 2003, J Biol Chem 278:3466-3473; U.S. Pat. No. 6,602,684; U.S. Ser. No. 10/277,370; U.S. Ser. No.
  • the “sugar engineered antibody” or “SEA technology” of Seattle Genetics functions by adding modified saccharides that inhibit fucosylation during production; see for example 20090317869, hereby incorporated by reference in its entirety.
  • Engineered glycoform typically refers to the different carbohydrate or oligosaccharide; thus an antibody can include an engineered glycoform.
  • engineered glycoform may refer to the IgG variant that comprises the different carbohydrate or oligosaccharide.
  • glycosylation patterns can depend on both the sequence of the protein (e.g., the presence or absence of particular glycosylation amino acid residues, discussed below), or the host cell or organism in which the protein is produced. Particular expression systems are discussed below.
  • N-linked refers to the attachment of the carbohydrate moiety to the side chain of an asparagine residue.
  • the tri-peptide sequences asparagine-X-serine and asparagine-X-threonine, where X is any amino acid except proline, are the recognition sequences for enzymatic attachment of the carbohydrate moiety to the asparagine side chain.
  • O-linked glycosylation refers to the attachment of one of the sugars N-acetylgalactosamine, galactose, or xylose, to a hydroxyamino acid, most commonly serine or threonine, although 5-hydroxyproline or 5-hydroxylysine may also be used.
  • Addition of glycosylation sites to the antibody is conveniently accomplished by altering the amino acid sequence such that it contains one or more of the above-described tri-peptide sequences (for N-linked glycosylation sites).
  • the alteration may also be made by the addition of, or substitution by, one or more serine or threonine residues to the starting sequence (for O-linked glycosylation sites).
  • the antibody amino acid sequence is preferably altered through changes at the DNA level, particularly by mutating the DNA encoding the target polypeptide at preselected bases such that codons are generated that will translate into the desired amino acids.
  • Another means of increasing the number of carbohydrate moieties on the antibody is by chemical or enzymatic coupling of glycosides to the protein. These procedures are advantageous in that they do not require production of the protein in a host cell that has glycosylation capabilities for N- and O-linked glycosylation.
  • the sugar(s) may be attached to (a) arginine and histidine, (b) free carboxyl groups, (c) free sulfhydryl groups such as those of cysteine, (d) free hydroxyl groups such as those of serine, threonine, or hydroxy-proline, (e) aromatic residues such as those of phenylalanine, tyrosine, or tryptophan, or (f) the amide group of glutamine.
  • Removal of carbohydrate moieties present on the starting antibody may be accomplished chemically or enzymatically.
  • Chemical deglycosylation requires exposure of the protein to the compound tritfluoromethanesulfonic acid, or an equivalent compound. This treatment results in the cleavage of most or all sugars except the linking sugar (N-acetylglucosamine or N-acetylgalactosamine), while leaving the polypeptide intact.
  • Chemical deglycosylation is described by Hakimuddin et al., 1987, Arch. Biochem. Biophys. 259:52 and by Edge et al., 1981, Anal, Biochem. 118:131, both entirely incorporated by reference.
  • Enzymatic cleavage of carbohydrate moieties on polypeptides can be achieved by the use of a variety of endo- and exo-glycosidases as described by Thotakura et al., 1987, Meth. Enzymol. 138:350, entirely incorporated by reference. Glycosylation at potential glycosylation sites may be prevented by the use of the compound tunicamycin as described by Duskin et al., 1982, J, Biol, Chem, 257:3105, entirely incorporated by reference, Tunicamycin blocks the formation of protein-N-glycoside linkages.
  • Another type of covalent modification of the antibody comprises linking the antibody to various nonproteinaceous polymers, including, but not limited to, various polyols such as polyethylene glycol, polypropylene glycol or polyoxyalkylenes, in the manner set forth in, for example, 2005-2006 PEG Catalog from Nektar Therapeutics (available at the Nektar website) U.S. Pat. No. 4,640,835; 4,496,689; 4,301,144; 4,670,417; 4,791,192 or 4,179,337, all entirely incorporated by reference.
  • amino acid substitutions may be made in various positions within the antibody to facilitate the addition of polymers such as PEG. See for example, U.S. Publication No. 2005/0114037A1, entirely incorporated by reference.
  • nucleic acids encoding the Fc variant antibodies of the invention include the nucleic acids encoding the Fc variant antibodies of the invention.
  • these are made using nucleic acids encoding each, that are combined into standard host cells (e.g. CHO cells, etc.) to produce the tetrameric structure of the antibody. If only one Fc variant engineered constant domain is being made, only a single nucleic acid will be used.
  • Fc variant antibodies of the invention in therapy will depend on the antigen binding component; e.g. in the case of full length standard therapeutic antibodies, on the antigen to which the antibody's Fv binds. That is, as will be appreciated by those in the art, the treatment of specific diseases can be done with the additional benefit of increased half life of the molecule. This can result in a variety of benefits, including, but not limited to, less frequent dosing (which can lead to better patient compliance), lower dosing, and lower production costs.
  • Formulations of the antibodies used in accordance with the present invention are prepared for storage by mixing an antibody having the desired degree of purity with optional pharmaceutically acceptable carriers, excipients or stabilizers (Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. [1980]), in the form of lyophilized formulations or aqueous solutions.
  • Acceptable carriers, excipients, or stabilizers are nontoxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid and methionine; preservatives (such as octadecyldimethylbenzyl ammonium chloride; hexamethonium chloride; benzalkonium chloride, benzethonium chloride; phenol, butyl or benzyl alcohol; alkyl parabens such as methyl or propyl paraben; catechol; resorcinol; cyclohexanol; 3-pentanol; and m-cresol); low molecular weight (less than about 10 residues) polypeptides; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, histidine,
  • the formulation herein may also contain more than one active compound as necessary for the particular indication being treated, preferably those with complementary activities that do not adversely affect each other.
  • the composition may comprise a cytotoxic agent, cytokine, growth inhibitory agent and/or small molecule antagonist.
  • cytotoxic agent cytokine
  • growth inhibitory agent cytokine
  • small molecule antagonist Such molecules are suitably present in combination in amounts that are effective for the purpose intended.
  • the active ingredients may also be entrapped in microcapsules prepared, for example, by coacervation techniques or by interfacial polymerization, for example, hydroxymethylcellulose or gelatin-microcapsules and poly-(methylmethacylate) microcapsules, respectively, in colloidal drug delivery systems (for example, liposomes, albumin microspheres, microemulsions, nano-particles and nanocapsules) or in macroemulsions.
  • colloidal drug delivery systems for example, liposomes, albumin microspheres, microemulsions, nano-particles and nanocapsules
  • the formulations to be used for in vivo administration should be sterile, or nearly so. This is readily accomplished by filtration through sterile filtration membranes.
  • Sustained-release preparations may be prepared. Suitable examples of sustained-release preparations include semipermeable matrices of solid hydrophobic polymers containing the antibody, which matrices are in the form of shaped articles, e.g. films, or microcapsules. Examples of sustained-release matrices include polyesters, hydrogels (for example, poly(2-hydroxyethyl-methacrylate), or poly(vinylalcohol)), polylactides (U.S. Pat. No. 3,773,919), copolymers of L-glutamic acid and .gamma.
  • sustained-release preparations include polyesters, hydrogels (for example, poly(2-hydroxyethyl-methacrylate), or poly(vinylalcohol)), polylactides (U.S. Pat. No. 3,773,919), copolymers of L-glutamic acid and .gamma.
  • ethyl-L-glutamate non-degradable ethylene-vinyl acetate
  • degradable lactic acid-glycolic acid copolymers such as the LUPRON DEPOTTM (injectable microspheres composed of lactic acid-glycolic acid copolymer and leuprolide acetate)
  • poly-D-( ⁇ )-3-hydroxybutyric acid While polymers such as ethylene-vinyl acetate and lactic acid-glycolic acid enable release of molecules for over 100 days, certain hydrogels release proteins for shorter time periods.
  • encapsulated antibodies When encapsulated antibodies remain in the body for a long time, they may denature or aggregate as a result of exposure to moisture at 37° C., resulting in a loss of biological activity and possible changes in immunogenicity. Rational strategies can be devised for stabilization depending on the mechanism involved. For example, if the aggregation mechanism is discovered to be intermolecular S—S bond formation through thio-disulfide interchange, stabilization may be achieved by modifying sulfhydryl residues, lyophilizing from acidic solutions, controlling moisture content, using appropriate additives, and developing specific polymer matrix compositions.
  • the antibodies and chemotherapeutic agents of the invention are administered to a subject, in accord with known methods, such as intravenous administration as a bolus or by continuous infusion over a period of time, by intramuscular, intraperitoneal, intracerobrospinal, subcutaneous, intra-articular, intrasynovial, intrathecal, oral, topical, or inhalation routes.
  • Intravenous or subcutaneous administration of the antibody is preferred,
  • therapy is used to provide a positive therapeutic response with respect to a disease or condition.
  • 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.
  • 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 patient survival rate; and (7) some relief from one or more symptoms associated with the disease or condition.
  • 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 including bone marrow aspiration (BMA) and counting of tumor cells in the circulation.
  • MRI magnetic resonance imaging
  • CT computed tomographic
  • BMA bone marrow aspiration
  • the subject undergoing therapy may experience the beneficial effect of an improvement in the symptoms associated with the disease.
  • B cell tumors the subject may experience a decrease in the so-called B symptoms, i.e., night sweats, fever, weight loss, and/or urticaria.
  • therapy with an Fc variant therapeutic agent may block and/or prolong the time before development of a related malignant condition, for example, development of multiple myeloma in subjects suffering from monoclonal gammopathy of undetermined significance (MGUS).
  • MGUS monoclonal gammopathy of undetermined significance
  • An improvement in the disease may be characterized as a complete response.
  • complete response is intended an absence of clinically detectable disease with normalization of any previously abnormal radiographic studies, bone marrow, and cerebrospinal fluid (CSF) or abnormal monoclonal protein in the case of myeloma.
  • CSF cerebrospinal fluid
  • Such a response may persist for at least 4 to 8 weeks, or sometimes 6 to 8 weeks, following treatment according to the methods of the invention.
  • an improvement in the disease may be categorized as being a partial response.
  • partial response is intended at least about a 50% decrease in all measurable tumor burden (i.e., the number of malignant cells present in the subject, or the measured bulk of tumor masses or the quantity of abnormal monoclonal protein) in the absence of new lesions, which may persist for 4 to 8 weeks, or 6 to 8 weeks.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • the efficient dosages and the dosage regimens for the Fc variant antibodies used in the present invention depend on the disease or condition to be treated and may be determined by the persons skilled in the art.
  • An exemplary, non-limiting range for a therapeutically effective amount of an Fc variant antibody used in the present invention is about 0, 1-100 mg/kg, such as about 0.1-50 mg/kg, for example about 0.1-20 mg/kg, such as about 0.1-10 mg/kg, for instance about 0.5, about such as 0.3, about 1, or about 3 mg/kg.
  • he antibody is administered in a dose of 1 mg/kg or more, such as a dose of from 1 to 20 mg/kg, e.g. a dose of from 5 to 20 mg/kg, e.g. a dose of 8 mg/kg.
  • a medical professional having ordinary skill in the art may readily determine and prescribe the effective amount of the pharmaceutical composition required.
  • a physician or a veterinarian could start doses of the medicament employed in the pharmaceutical 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.
  • the Fc variant antibody is administered by infusion in a weekly dosage of from 10 to 500 mg/kg such as of from 200 to 400 mg/kg Such administration may be repeated, e.g., 1 to 8 times, such as 3 to 5 times.
  • the administration may be performed by continuous infusion over a period of from 2 to 24 hours, such as of from 2 to 12 hours.
  • the Fc variant antibody is administered by slow continuous infusion over a long period, such as more than 24 hours, if required to reduce side effects including toxicity.
  • the Fc variant antibody is administered in a weekly dosage of from 250 mg to 2000 mg, such as for example 300 mg, 500 mg, 700 mg, 1000 mg, 1500 mg or 2000 mg, for up to 8 times, such as from 4 to 6 times.
  • the administration may be performed by continuous infusion over a period of from 2 to 24 hours, such as of from 2 to 12 hours. Such regimen may be repeated one or more times as necessary, for example, after 6 months or 12 months.
  • the dosage may be determined or adjusted by measuring the amount of compound of the present invention in the blood upon administration by for instance taking out a biological sample and using anti-idiotypic antibodies which target the antigen binding region of the Fc variant antibody.
  • the Fc variant antibody is administered once weekly for 2 to 12 weeks, such as for 3 to 10 weeks, such as for 4 to 8 weeks.
  • the Fc variant antibody is administered by maintenance therapy, such as, e.g., once a week for a period of 6 months or more.
  • the Fc variant antibody is administered by a regimen including one infusion of an Fc variant antibody followed by an infusion of an Fc variant antibody conjugated to a radioisotope.
  • the regimen may be repeated, e.g., 7 to 9 days later.
  • treatment according to the present invention may be provided as a daily dosage of an antibody in an amount of about 0.1-100 mg/kg, such as 0.5, 0.9, 1.0, 1.1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 40, 45, 50, 60, 70, 80, 90 or 100 mg/kg, per day, on at least one of day 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40, or alternatively, at least one of week 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 after initiation of treatment, or any combination thereof, using single or divided doses of every 24, 12, 8, 6, 4, or 2 hours, or any combination thereof.
  • an antibody in an amount of about 0.1-100 mg/kg, such as 0.5, 0.9, 1.0, 1.1, 1.5, 2, 3, 4, 5, 6,
  • the Fc variant antibody molecule thereof is used in combination with one or more additional therapeutic agents, e.g. a chemotherapeutic agent.
  • DNA damaging chemotherapeutic agents include topoisomerase I inhibitors (e.g., irinotecan, topotecan, camptothecin and analogs or metabolites thereof, and doxorubicin); topoisomerase II inhibitors (e.g., etoposide, teniposide, and daunorubicin); alkylating agents (e.g., melphalan, chlorambucil, busulfan, thiotepa, ifosfamide, carmustine, lomustine, semustine, streptozocin, decarbazine, methotrexate, mitomycin C, and cyclophosphamide); DNA intercalators (e.g., cisplatin, oxaliplatin, and carboplatin); DNA intercalators and free
  • Chemotherapeutic agents that disrupt cell replication include: paclitaxel, docetaxel, and related analogs; vincristine, vinblastin, and related analogs; thalidomide, lenalidomide, and related analogs (e.g., CC-5013 and CC-4047); protein tyrosine kinase inhibitors (e.g., imatinib mesylate and gefitinib); proteasome inhibitors (e.g., bortezomib); NF- ⁇ B inhibitors, including inhibitors of I ⁇ B kinase; antibodies which bind to proteins overexpressed in cancers and thereby downregulate cell replication (e.g., trastuzumab, rituximab, cetuximab, and bevacizumab); and other inhibitors of proteins or enzymes known to be upregulated, over-expressed or activated in cancers, the inhibition of which downregulates cell replication.
  • the antibodies of the invention can be used prior to, concurrent with, or after treatment with Velcade® (bortezomib).
  • Amino acid modifications were engineered in the Fc region of IgG antibodies to improve their affinity for the neonatoal Fc receptor FcRn.
  • Variants were screened in the context of a number of different human IgG constant chains ( FIG. 2 ), including IgG1, IgG2, and a hybrid IgG sequences that contains the CH1 and upper hinge of IgG1 and the Fc region of IgG2. It will be appreciated by those skilled in the art that because of the different interactions of the IgG1 and IgG2 Fc region with Fc ⁇ Rs and complement, these different parent Fc regions will have different Fc ⁇ R ⁇ and complement-mediated effector function properties. Exemplary sequences of Fc variants in the context of these parent IgG constant chains are shown in FIG. 3 .
  • VH and VL are those of a humanized version of the antibody A4.6.1, also referred to as bevacizumab (Avastin®), which is approved for the treatment of a variety of cancers.
  • Avastin® bevacizumab
  • the amino acid sequences of the VH and VL regions of this antibody are shown in FIG. 4 .
  • Genes encoding the heavy and light chains of the anti-VEGF antibodies were constructed in the mammalian expression vector pTT5.
  • Human IgG1 and IgG2 constant chain genes were obtained from IMAGE clones and subcloned into the pTT5 vector.
  • the IgG1/2 gene was constructed using PCR mutagenesis.
  • VH and VL genes encoding the anti-VEGF antibodies were synthesized commercially (Blue Heron Biotechnologies, Bothell Wash.), and subcloned into the vectors encoding the appropriate CL, IgG1, IgG2, and IgG1/2 constant chains, Amino acid modifications were constructed using site-directed mutagenesis using the QuikChange® site-directed mutagenesis methods (Stratagene, La Jolla Calif.). All DNA was sequenced to confirm the fidelity of the sequences.
  • Plasmids containing heavy chain gene (VH—C ⁇ 1-C ⁇ 2-C ⁇ 3) were co-transfected with plasmid containing light chain gene (VL-C ⁇ ) into 293E cells using lipofectamine (Invitrogen, Carlsbad Calif.) and grown in FreeStyle 293 media (Invitrogen, Carlsbad Calif.). After 5 days of growth, the antibodies were purified from the culture supernatant by protein A affinity using the MabSelect resin (GE Healthcare), Antibody concentrations were determined by bicinchoninic acid (BCA) assay (Pierce).
  • BCA bicinchoninic acid
  • VEGF binding was monitored using surface plasmon resonance (SPR, Biacore), performed using a Biacore 3000 instrument.
  • Recombinant VEGF (VEGF-165, PeproTech, Rocky Hill, N.J.) was adhered to a CM5 chip surface by coupling with N-hydroxysuccinimide/N-ethyl-N′-(-3-dimethylamino-propyl) carbodiimide (NHS/EDC) using standard methods.
  • WT and variant antibodies were injected as analytes, and response, measured in resonance units (RU), was acquired.
  • the dissociation phase was too slow to measure true equilibrium constants, and so relative binding was determined by measuring RU's at the end of the association phase, which should be proportional to the protein concentration (which is held constant in the experiment) and the association rate constant.
  • the data show that the variant anti-VEGF antibodies maintain binding to antigen, in contrast to the negative control anti-Her2 antibody which does not bind VEGF.
  • Binding of variant antibodies to human FcRn was measured at pH 6.0, the pH at which it is naturally bound in endosomes.
  • Vectors encoding beta 2 microglobulin and His-tagged alpha chain genes of FcRn were constructed, co-transfected into 293T cells, and purified using nickel chromatography.
  • Antibody affinity for human FcRn (hFcRn) at pH 6.0 was measured on a Biacore 3000 instrument by coupling human FcRn to a CM5 chip surface using standard NHS/EDC chemistry.
  • WT and variant antibodies were used in the mobile phase at 25-100 nM concentration and response was measured in resonance units.
  • Association and dissocation phases at pH 6.0 were acquired, followed by an injection of pH 7.4 buffer to measure release of antibody from receptor at the higher pH. A cycle with antibody and buffer only provided baseline response, which was subtracted from each sample sensorgram.
  • FIG. 6 shows Biacore sensorgrams for binding of native IgG1 and select Fc variant antibodies to human FcRn at the two relevant pH's.
  • the data show that wild-type and variant antibodies bind readily to FcRn chip at pH 6.0 and dissociate slowly at that pH, as they would in the endosome, yet release rapidly at pH7.4, as they would upon recycling of endosome to the membrane and exposure to the higher pH of serum.
  • the FcRn association/dissociation curves did not fit to a simple Langmuir model, possibly due to the antibody and receptor multi-valency or chip heterogeneity.
  • Pseudo-Ka values (referred to as Ka*) were determined by fitting to a conformational change model with the change in refractive index (RI) fixed at 0 RU. These values for select variant antibodies are plotted in FIG. 7 .
  • mice that are homozygous knock-outs for murine FcRn and heterozygous knock-ins of human FcRn (mFcRn ⁇ / ⁇ , hFcRn + ) (Petkova et al., 2006, Int. Immunol 18(12): 1759-69, entirely incorporated by reference), herein referred to as hFcRn or hFcRn + mice.
  • hFcRn or hFcRn + mice A single, intravenous tail vein injection of anti-VEGF antibody (2 mg/kg) was given to groups of 4-7 female mice randomized by body weight (20-30 g range). Blood ( ⁇ 50 ul) was drawn from the orbital plexus at each time point, processed to serum, and stored at ⁇ 80° C. until analysis. Study durations were 28 or 49 days.
  • Antibody concentrations were determined using two ELISA assays.
  • Study 1 and Study 2 goat anti-human Fc antibody (Jackson Immune research) was adhered to the plate, wells were washed with PBST (phosphate buffered saline with 0.05% Tween) and blocked with 3% BSA in PBST. Serum or calibration standards were the added, followed by PBST washing, addition of europium labeled anti-human IgG (Perkin Elmer), and further PBST washing. The time resolved fluorescence signal was collected.
  • PBST phosphate buffered saline with 0.05% Tween
  • VEGF-165 vascular endothelial growth factor
  • P257N and P257L serum concentration was detected using a similar ELISA, but recombinant VEGF (VEGF-165, PeproTech, Rocky Hill, N.J.) was used as capture reagent and detection was carried out with biotinylated anti-human kappa antibody and europium-labeled streptavidin.
  • PK parameters were determined for individual mice with a non-compartmental model using WinNonLin (Pharsight Inc, Mountain View Calif.). Nominal times and dose were used with uniform weighing of points. The time points used (lambda Z ranges) were from 4 days to the end of the study, although all time points were used for the faster clearing mutants, P257N and P257L.
  • FIG. 8 a - 8 b shows serum concentration data for WT and variant IgG1 (Study 3) and IgG2 (Study 5) antibodies respectively.
  • Fitted PK parameters from all in vivo PK studies carried out in mFcRn ⁇ / ⁇ hFcRn + mice are provided in FIG. 9 , PK data include half-life, which represents the beta phase that characterizes elimination of antibody from serum, Cmax, which represents the maximal observed serum concentration, AUG, which represents the area under the concetration time curve, and clearance, which represents the clearance of antibody from serum.
  • Cmax which represents the maximal observed serum concentration
  • AUG which represents the area under the concetration time curve
  • clearance which represents the clearance of antibody from serum.
  • PK properties of biologics in non-human primates are well-established to be predictive of their properties in humans.
  • a PK study was carried out in cynomolgus monkeys ( macaca fascicularis ) in order to evaluate the capacity of the variant anti-VEGF antibodies to improve serum half-life in non-human primates.
  • the PK of the variants were studied in vivo in non-human primates.
  • Male cynomolgus monkeys macaca fascicularis , also called crab-eating Macaque) weighing 2.3-5.1 kg were randomized by weight and divided into 5 groups with 3 monkeys per group. The monkeys were given a single, 1 hour peripheral vein infusion of 4 mg/kg antibody. Blood samples (1 ml) were drawn from a separate vein from 5 minutes to 90 days after completion of the infusion, processed to serum and stored at ⁇ 70 C. Animals were not harmed during these studies.
  • Antibody concentrations were determined using the VEGF capture method as described above.
  • PK parameters were determined by fitting the concentrations versus time to a non-compartmental model as was done in the mouse PK studies. However, time points from day 10 to day 90 were used for PK parameter determinations. The PK results are plotted in FIG. 11 , and the fitted parameters are provided in FIG. 12 . The results show that the variants enhanced the in vivo half-life of antibody up to 3.2-fold. In the best case (the 428L/434S variant) half-life was extended from 9.7 days to 31.1 days.
  • PK results obtained in cynomolgus monkeys are consistent with those obtained in mFcRn ⁇ / ⁇ hFcRn + mice, validating the hFcRn mouse model as a system for assessing the in vivo PK properties of the variants, and supporting the conclusions from those studies.
  • Variants were engineered to further screen for modifications that extend in vivo halt-life. Designed substitutions are shown in FIG. 13 , Variants were constructed in the context of an antibody with the bevacizumab variant region and IgG1/2 N434S constant region; however, variants may be constructed in any IgG isotype. Variants were constructed, expressed, and purified as described above.
  • Variants were screened for binding to human FcRn at pH 6.0 by Biacore.
  • Anti-VEGF antibodies were captured to a VEGF coupled chip, a single concentration of FcRn analyte was flowed over the chip (association phase), and then buffer was washed over to dissociate FcRn analyte (dissociation phase).
  • the dissociation off-rate (k off ) was determined by fitting the dissociation phase data to a 1:1 Langmuir dissociation model. The results are shown numerically in FIG. 14 , and plotted in FIG. 15 . As can be seen, a number of the designed variants improve FcRn binding (reduce the k off ) relative to the IgG1/2 N434S background.
  • Beneficial substitutions include but are not limited to T307Q, Q311I, Q311V, A378V, S426V, S426T, Y436I, and Y436V.
  • the successful engineering at positions 378 and 426 is surprising giving that they are more distal to the FcRn binding interface on Fc.
  • Variants were constructed, expressed, and purified as described above. Variants were screened for binding to human FcRn at pH 6.0 by Biacore. Anti-VEGF antibodies were captured to a VEGF coupled chip, a single concentration of FcRn analyte was flowed over the chip (association phase), and then buffer was washed over to dissociate FcRn analyte (dissociation phase). The dissociation off-rate (k off ) was determined by fitting the dissociation phase data to a 1:1 Langmuir dissociation model. The results are shown numerically in FIG. 21 , and plotted in FIG. 22 . As can be seen, a number of the designed variants improve FcRn binding (reduce the k off ).
  • FIG. 23 shows mean serum concentration data for Fc variant and IgG1/2 parent anti-VEGF antibodies. Fitted half-lives of individual mice and means are provided in FIG. 24 .
  • FIG. 25 shows a scatter plot of the fitted half-lives from the individual mice in the study. The results indicate that the engineered Fc variants extend half-life relative to the parent IgG1/2 antibody, as well as the IgG1/2 N434S variant.

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Abstract

The invention relates generally to compositions and methods for altering the serum half-life in vivo of an antibody.

Description

  • This application claims the benefit under 35 U.S.C. 119 to U.S. Provisional Application Ser. No. 61/392,115, filed Oct. 12, 2010, and is also a continuation-in-part of U.S. Ser. No. 12/341,769, filed Dec. 22, 2008, which are both incorporated herein by reference in their entirety.
    • FIELD OF THE INVENTION
  • The present application relates to optimized IgG immunoglobulin variants that extend antibody half-life in vivo, and their application, particularly for therapeutic purposes.
    • BACKGROUND OF THE INVENTION
  • Antibodies are immunological proteins that bind a specific antigen. In most mammals, including humans and mice, antibodies are constructed from paired heavy and light polypeptide chains. Each chain is made up of individual immunoglobulin (Ig) domains, and thus the generic term immunoglobulin is used for such proteins. Each chain is made up of two distinct regions, referred to as the variable and constant regions. The light and heavy chain variable regions show significant sequence diversity between antibodies, and are responsible for binding the target antigen. The constant regions show less sequence diversity, and are responsible for binding a number of natural proteins to elicit important biochemical events. In humans there are five different classes of antibodies including IgA (which includes subclasses IgA1 and IgA2), IgD, IgE, IgG (which includes subclasses IgG1, IgG2, IgG3, and IgG4), and IgM. The distinguishing feature between these antibody classes is their constant regions, although subtler differences may exist in the V region, IgG antibodies are tetrameric proteins composed of two heavy chains and two light chains. The IgG heavy chain is composed of four immunoglobulin domains linked from N- to C-terminus in the order VH—CH1-CH2-CH3, referring to the heavy chain variable domain, heavy chain constant domain 1, heavy chain constant domain 2, and heavy chain constant domain 3 respectively (also referred to as VH—Cγ1-Cγ2-Cγ3, referring to the heavy chain variable domain, constant gamma 1 domain, constant gamma 2 domain, and constant gamma 3 domain respectively). The IgG light chain is composed of two immunoglobulin domains linked from N- to C-terminus in the order VL-CL, referring to the light drain variable domain and the light chain constant domain respectively.
  • In IgG, a site on Fc between the Cγ2 and Cγ3 domains mediates interaction with the neonatal receptor FcRn. Binding to FcRn recycles endocytosed antibody from the endosome back to the bloodstream (Raghavan et al., 1996, Annu Rev Cell Dev Biol 12:181-220; Ghetie et al., 2000, Annu Rev Immunol 18:739-766, both entirely incorporated by reference). This process, coupled with preclusion of kidney filtration due to the large size of the full-length molecule, results in favorable antibody serum half-lives ranging from one to three weeks. Binding of Fc to FcRn also plays a key role in antibody transport. The binding site on Fc for FcRn is also the site at which the bacterial proteins A and G bind. The tight binding by these proteins is typically exploited as a means to purify antibodies by employing protein A or protein G affinity chromatography during protein purification. Thus the fidelity of this region on Fc is important for both the clinical properties of antibodies and their purification. Available structures of the rat Fc/FcRn complex (Burmeister et al., 1994, Nature, 372:379-383; Martin et al., 2001, Mol Cell 7:867-877, both entirely incorporated by reference), and of the complexes of Fc with proteins A and G (Deisenhofer, 1981, Biochemistry 20:2361-2370; Sauer-Eriksson et al., 1995, Structure 3:265-278; Tashiro et al., 1995, Curr Opin Struct Biol 5:471-481, all entirely incorporated by reference), provide insight into the interaction of Fc with these proteins. The FcRn receptor is also responsible for the transfer of IgG to the neonatal gut and to the lumen of the intestinal epithelia in adults (Ghetie and Ward, Annu. Rev. Immunol, 2000, 18:739-766; Yoshida et al., Immunity, 2004, 20(6):769-783, both entirely incorporated by reference).
  • Antibodies have serum half-lives in vivo ranging from one to three weeks. This favorable property is due to the preclusion of kidney filtration due to the large size of the full-length molecule, and interaction of the antibody Fc region with the neonatal Fc receptor FcRn. Binding to FcRn recycles endocytosed antibody from the endosome back to the bloodstream (Raghavan et al., 1996, Annu Rev Cell Dev Biol 12:181-220; Ghetie et al., 2000, Annu Rev Immunol 18:739-766, both entirely incorporated by reference).
  • Other properties of the antibody may determine its clearance rate (e.g. stability and half-life) in vivo. In addition to antibody binding to the FcRn receptor, other factors that contribute to clearance and half-life are serum aggregation, enzymatic degradation in the serum, inherent immunogenicity of the antibody leading to clearing by the immune system, antigen-mediated uptake, FcR (non-FcRn) mediated uptake and non-serum distribution (e.g. in different tissue compartments).
  • There is a need for antibody modifications that improve the pharmacokinetic properties of antibodies. The present application meets these and other needs and provides novel engineered variants in the constant regions to improve serum half-life.
    • BRIEF SUMMARY OF THE INVENTION Problem to be Solved
  • Accordingly, one problem to be solved is to increase serum half life of antibodies by altering the constant domains, thus allowing the same constant regions to be used with different antigen binding sequences, e.g. the variable regions including the CDRs, and minimizing the possibility of immunogenic alterations. Thus providing antibodies with constant region variants with extended half-life provides a modular approach to improving the pharmacokinetic properties of antibodies, as described herein. In addition, due to the methodologies outlined herein, the possibility of immunogenicity resulting from the FcRn variants is significantly reduced by importing variants from different IgG isotypes such that serum half-life is increased without introducing significant immunogenicity.
    • SUMMARY
  • In one aspect, the present invention provides an antibody comprising a variant Fc region as compared to a parent Fc region, wherein the variant Fc region comprises a first mutation which is a serine at position 434 and a second mutation selected from the group: an isoleucine at position 311, a valine at position 311, an isoleucine at position 436, and a valine at position 436. In a further aspect, the antibody has increased serum half-life as compared to an antibody comprising the parent Fc region, wherein numbering is according to the EU index. In a still further aspect, the antibody has increased binding affinity to a human FcRn receptor as compared to an antibody comprising the parent Fc region, wherein numbering is according to the EU index.
  • In one embodiment, the present invention provides nucleic acids encoding any of the variant Fc regions described herein.
  • In a further embodiment, the present invention provides host cells comprising a nucleic acid encoding any of the variant Fc regions described herein.
  • In one aspect, the present invention provides methods of administering an antibody to a subject, where the antibody comprises a variant Fc region as compared to a parent Fc region, wherein the variant Fc region comprises a first mutation which is a serine at position 434 and a second mutation selected from the group: an isoleucine at position 311, a valine at position 311, an isoleucine at position 436, and a valine at position 436, where the antibody has increased serum half-life as compared to an antibody comprising the parent Fc region, and wherein numbering is according to the EU index.
    • BRIEF DESCRIPTION OF THE DRAWINGS
  • FIG. 1. Sequence alignments of human IgG constant heavy chains. Gray indicates differences from IgG1, and boxed residues indicate common allotypic variations in the human population.
  • FIG. 2. (SEQ ID NO: 1-6) Amino acid sequences of constant regions used in the invention.
  • FIG. 3. (SEQ ID NO: 7-8) Amino acid sequences of exemplary variant constant regions.
  • FIG. 4. (SEQ ID NO: 9-10) Amino acid sequences of VH and VL variable regions used in the invention.
  • FIG. 5. Relative VEGF binding by WT and select variant IgG1 anti-VEGF antibodies. The plot shows the Biacore response units (RU) at the end of the association phase for binding of antibody analyte to immobilized VEGF antigen. Anti-Her2 IgG1 antibody was used as a negative control.
  • FIG. 6. Biacore sensorgrams of WT and variant IgG1 antibodies to immobilized human FcRn at low (6.0) and high (7.4) pH.
  • FIG. 7. FcRn binding affinities of WT and select variant IgG1 antibodies to human FcRn at pH 6.0 as determined by Biacore. The graph shows a plot of the pseudo-affinity constant (Ka*), on a log scale.
  • FIG. 8 a-8 b. In vivo pharmacokinetics of WT and variant antibodies in mFcRn−/− hFcRn+ mice. The graphs plot the serum concentration of antibody versus time after a single intravenous dose. FIG. 8 a shows data from one of the 4 studies carried out with IgG1 antibodies (Study 3), and FIG. 8 b shows data from a study carried out with IgG2 antibodies (Study 5).
  • FIG. 9. Fitted PK parameters from all in vivo PK studies carried out in mFcRn−/− hFcRn+ mice with variant and WT antibodies, n represents the number of mice per group, with Mean and standard deviation (SD) data provided for PK parameters. Half-Life represents the beta phase that characterizes elimination of antibody from serum. Cmax is the maximal observed serum concentration, AUG is the area under the concetration time curve, and clearance is the clearance of antibody from serum. Fold half-life is calculated as the half-life of variant antibody over that of the WT IgG1 or IgG2 parent within each study.
  • FIG. 10 a-10 b. Relative binding of variant IgG1 anti-VEGF antibodies to cynomolgus monkey and human FcRn as determined by Biacore. FIG. 10 a shows the data in tabular form. FIG. 10 b shows a plot of the data.
  • FIG. 11. In vivo pharmacokinetics of WT and variant antibodies in cynomolgus monkeys. The graphs plot the serum concentration of antibody versus time after a single intravenous dose.
  • FIG. 12. Fitted PK parameters from the in vivo PK study in cynomolgus monkeys with variant and WT antibodies. Parameters are as described in FIG. 9.
  • FIG. 13. Designed Fc variants. Variants are screened using the described methods in order to obtain modifications that extend the in vivo half-life of antibodies.
  • FIG. 14. Screen of engineered Fc variants for binding to human FcRn. The table shows the off-rate (koff) for binding of each variant to human FcRn at pH 6.0 by Biacore.
  • FIG. 15. Graph of koff for screened Fc variants (data plotted are from FIG. 14).
  • FIG. 16. Affinities of select variants for human FcRn at pH 6.0 based on a FcRn concentration series Biacore experiment. The data show the on and off kinetic rate constants (kon and koff respectively), and the association and dissociation equilibrium constants (KA and KD respectively), as well as the fold improvement in KD and koff relative to WT IgG1 and IgG1/2N434S.
  • FIG. 17. Plot off affinities of select variants for human FcRn at pH 6.0 as determined by Biacore. Values are plotted from FIG. 16.
  • FIG. 18. Plot off affinities of select variants for human FcRn at pH 6.0 as determined by Biacore. Values are plotted from FIG. 16.
  • FIG. 19. Designed single variants
  • FIG. 20. Designed combination variants
  • FIG. 21. Affinities of select variants for human FcRn at pH 6.0 based on a FcRn concentration series Biacore experiment. The data show the dissociation equilibrium constant KD, as well as the fold improvement in KD relative to the IgG1/2 parent.
  • FIG. 22. Plot off affinities of select variants for human FcRn at pH 6.0 as determined by Biacore. Values are plotted from FIG. 21.
  • FIG. 23. In vivo pharmacokinetics of IgG1/2 variant antibodies in mFcRn−/− hFcRn+ mice. The graphs plot the serum concentration of antibody versus time after a single intravenous dose.
  • FIG. 24. Fitted half-lives (t½) from the PK study in hFcRn+ mice, n=number of mice, columns n1-n5 show the half-lives of the individual mice in each group, and the average half-life and standard deviation are shown in the last two columns.
  • FIG. 25. Scatter plot of half-life results from PK study in hFcRn+ mice. Data are plotted from FIG. 24. Each dot represents the t½ of an individual mouse within each variant group, and the line indicates the average.
    •  DETAILED DESCRIPTION OF THE INVENTION I. Overview
  • The present invention discloses the generation of novel variants of Fc domains, including those found in antibodies, Fc fusions, and immuno-adhesions, which have an increased binding to the FcRn receptor. As noted herein, binding to FcRn results in longer serum retention in vivo. These variants of Fc domains are also referred to herein as “Fc variants” or “FcRn variants”.
  • The substitutions in the Fc domains (“Fc substitutions”) are chosen such that the resultant proteins (“Fc proteins”) show improved serum half-life in vivo as compared to the wild type protein. In order to increase the retention of the Fc proteins in vivo, the increase in binding affinity must be at around pH 6 while maintaining lower affinity at around pH 7.4. Although still under examination, Fc regions are believed to have longer half-lives in vivo, because binding to FcRn at pH 6 in an endosome sequesters the Fc (Ghetie and Ward, 1997 Immunol Today. 18(12): 592-598, entirely incorporated by reference). The endosomal compartment then recycles the Fc to the cell surface. Once the compartment opens to the extracellular space, the higher pH, ˜7.4, induces the release of Fc back into the blood. In mice, Dall' Acqua et al. showed that Fc mutants with increased FcRn binding at pH 6 and pH 7.4 actually had reduced serum concentrations and the same half life as wild-type Fc (Dall' Acqua et al. 2002, J. Immunol. 169:5171-5180, entirely incorporated by reference). The increased affinity of Fc for FcRn at pH 7.4 is thought to forbid the release of the Fc back into the blood. Therefore, the Fc mutations that will increase Fc's half-life in vivo will ideally increase FcRn binding at the lower pH while still allowing release of Fc at higher pH. The amino acid histidine changes its charge state in the pH range of 6.0 to 7.4. Therefore, it is not surprising to find His residues at important positions in the Fc/FcRn complex.
  • An additional aspect of the invention is the increase in FcRn binding over wild type specifically at lower pH, about pH 6.0, to facilitate Fc/FcRn binding in the endosome. Also disclosed are Fc variants with altered FcRn binding and altered binding to another class of Fc receptors, the FcγR's (sometimes written FcgammaR's) as differential binding to FcγRs, particularly increased binding to FcγRIIIb and decreased binding to FcγRIIb, has been shown to result in increased efficacy.
  • In addition, many embodiments of the invention rely on the “importation” of substitutions at particular positions from one IgG isotype into another, thus reducing or eliminating the possibility of unwanted immunogenicity being introduced into the variants. That is, IgG1 is a common isotype for therapeutic antibodies for a variety of reasons, including high effector function. IgG2 residues at particular positions can be introduced into the IgG1 backbone to result in a protein that exhibits longer serum half-life.
  • In other embodiments, non-isotypic amino acid changes are made, to improve binding to FcRn and/or to increase in vivo serum halt-life, and/or to allow accommodations in structure for stability, etc. as is more further described below.
  • As will be appreciated by those in the art and described below, a number of factors contribute to the in vivo clearance, and thus the half-life, of antibodies in serum. One factor involves the antigen to which the antibody binds; that is, antibodies with identical constant regions but different variable regions (e.g. Fv domains), may have different half-lives due to differential ligand binding effects. However, the present invention demonstrates that while the absolute half life of two different antibodies may differ due to these antigen specificity effects, the FcRn variants described herein, can transfer to different ligands to give the same trends of increasing half-life. That is, in general, the relative “order” of the FcRn binding/half life increases will track to antibodies with the same variants of antibodies with different Fvs as is discussed herein.
    • II. Description of the Invention A. Antibodies
  • The present invention relates to the generation of Fc variants of antibodies, generally therapeutic antibodies. As is discussed below, the term “antibody” is used generally. Antibodies that find use in the present invention can take on a number of formats as described herein, including traditional antibodies as well as antibody derivatives, fragments and mimetics, described below. In general, the term “antibody” includes any polypeptide that includes at least one constant domain, including, but not limited to, CH1, CH2, CH3 and CL.
  • Traditional antibody structural units typically comprise a tetramer. Each tetramer is typically composed of two identical pairs of polypeptide chains, each pair having one “light” (typically having a molecular weight of about 25 kDa) and one “heavy” chain (typically having a molecular weight of about 50-70 kDa). Human light chains are classified as kappa and lambda light chains. The present invention is directed to the IgG class, which has several subclasses, including, but not limited to IgG1, IgG2, IgG3, and IgG4. Thus, “isotype” as used herein is meant any of the subclasses of immunoglobulins defined by the chemical and antigenic characteristics of their constant regions. It should be understood that therapeutic antibodies can also comprise hybrids of isotypes and/or subclasses. For example, as shown herein, the present invention covers Fc variant engineering of IgG1/G2 hybrids.
  • The amino-terminal portion of each chain includes a variable region of about 100 to 110 or more amino acids primarily responsible for antigen recognition, generally referred to in the art and herein as the “Fv domain” or “Fv region”. In the variable region, three loops are gathered for each of the V domains of the heavy chain and light chain to form an antigen-binding site. Each of the loops is referred to as a complementarity-determining region (hereinafter referred to as a “CDR”), in which the variation in the amino acid sequence is most significant. “Variable” refers to the fact that certain segments of the variable region differ extensively in sequence among antibodies. Variability within the variable region is not evenly distributed. Instead, the V regions consist of relatively invariant stretches called framework regions (FRs) of 15-30 amino acids separated by shorter regions of extreme variability called “hypervariable regions” that are each 9-15 amino acids long or longer.
  • Each VH and VL is composed of three hypervariable regions (“complementary determining regions,” “CDRs”) and four FRs, arranged from amino-terminus to carboxy-terminus in the following order: FR1-CDR1-FR2-CDR2-FR3-CDR3-FR4.
  • The hypervariable region generally encompasses amino acid residues from about amino acid residues 24-34 (LCDR1; “L” denotes light chain), 50-56 (LCDR2) and 89-97 (LCDR3) in the light chain variable region and around about 31-35B (HCDR1; “H” denotes heavy chain), 50-65 (HCDR2), and 95-102 (HCDR3) in the heavy chain variable region; Kabat et al., SEQUENCES OF PROTEINS OF IMMUNOLOGICAL INTEREST, 5th Ed. Public Health Service, National Institutes of Health, Bethesda, Md. (1991) and/or those residues forming a hypervariable loop (e.g. residues 26-32 (LCDR1), 50-52 (LCDR2) and 91-96 (LCDR3) in the light chain variable region and 26-32 (HCDR1), 53-55 (HCDR2) and 96-101 (HCDR3) in the heavy chain variable region; Chothia and Lesk (1987) J. Mol. Biol. 196:901-917. Specific CDRs of the invention are described below.
  • Throughout the present specification, the Kabat numbering system is generally used when referring to a residue in the variable domain (approximately, residues 1-107 of the light chain variable region and residues 1-113 of the heavy chain variable region) (e.g, Kabat et al., supra (199.1)).
  • The CDRs contribute to the formation of the antigen-binding, or more specifically, epitope binding site of antibodies. “Epitope” refers to a determinant that interacts with a specific antigen binding site in the variable region of an antibody molecule known as a paratope. Epitopes are groupings of molecules such as amino acids or sugar side chains and usually have specific structural characteristics, as well as specific charge characteristics. A single antigen may have more than one epitope.
  • The epitope may comprise amino acid residues directly involved in the binding (also called immunodominant component of the epitope) and other amino acid residues, which are not directly involved in the binding, such as amino acid residues which are effectively blocked by the specifically antigen binding peptide; in other words, the amino acid residue is within the footprint of the specifically antigen binding peptide.
  • Epitopes may be either conformational or linear. A conformational epitope is produced by spatially juxtaposed amino acids from different segments of the linear polypeptide chain. A linear epitope is one produced by adjacent amino acid residues in a polypeptide chain. Conformational and nonconformational epitopes may be distinguished in that the binding to the former but not the latter is lost in the presence of denaturing solvents.
  • An epitope typically includes at least 3, and more usually, at least 5 or 8-10 amino acids in a unique spatial conformation. Antibodies that recognize the same epitope can be verified in a simple immunoassay showing the ability of one antibody to block the binding of another antibody to a target antigen, for example “binning.”
  • As will be appreciated by those in the art, a wide variant of antigen binding domains, e.g. Fv regions, may find use in the present invention. Virtually any antigen may be targeted by the IgG variants, including but not limited to proteins, subunits, domains, motifs, and/or epitopes belonging to the following list of target antigens, which includes both soluble factors such as cytokines and membrane-bound factors, including transmembrane receptors: 17-IA, 4-1BB, 4Dc, 6-keto-PGF1a, 8-iso-PGF2a, 8-oxo-dG, A1 Adenosine Receptor, A33, ACE, ACE-2, Activin, Activin A, Activin AB, Activin B, Activin C, Activin RIA, Activin RIA ALK-2, Activin RIB ALK-4, Activin RIIA, Activin RIIB, ADAM, ADAM10, ADAM12, ADAM15, ADAM17/TACE, ADAMS, ADAM9, ADAMTS, ADAMTS4, ADAMTS5, Addressins, aFGF, ALCAM, ALK, ALK-1, ALK-7, alpha-1-antitrypsin, alpha-V/beta-1 antagonist, ANG, Ang, APAF-1, APE, APJ, APP, APRIL, AR, ARC, ART, Artemin, anti-Id, ASPARTIC, Atrial natriuretic factor, av/b3 integrin, Ax1, b2M, B7-1, B7-2, B7-H, B-lymphocyte Stimulator (BlyS), BACE, BACE-1, Bad, BAFF, BAFF-R, Bag-1, BAK, Bax, BCA-1, BCAM, Bcl, BCMA, BDNF, b-ECGF, bFGF, BID, Bik, BIM, BLC, BL-CAM, BLK, BMP, BMP-2 BMP-2a, BMP-3 Osteogenin, BMP-4 BMP-2b, BMP-5, BMP-6 Vgr-1, BMP-7 (OP-1), BMP-8 (BMP-8a, OP-2), BMPR, BMPR-IA (ALK-3), BMPR-IB (ALK-6), BRK-2, RPK-1, BMPR-II (BRK-3), BMPs, b-NGF, BOK, Bombesin, Bone-derived neurotrophic factor, BPDE, BPDE-DNA, BTC, complement factor 3 (C3), C3a, C4, C5, C5a, C10, CA125, CAD-8, Calcitonin, cAMP, carcinoembryonic antigen (CEA), carcinoma-associated antigen, Cathepsin A, Cathepsin B, Cathepsin C/DPPI, Cathepsin D, Cathepsin E, Cathepsin H, Cathepsin L, Cathepsin O, Cathepsin S, Cathepsin V, Cathepsin X/Z/P, CBL, CCI, CCK2, CCL, CCL1, CCL11, CCL12, CCL13, CCL14, CCL15, CCL16, CCL17, CCL18, CCL19, CCL2, CCL20, CCL21, CCL22, CCL23, CCL24, CCL25, CCL26, CCL27, CCL28, CCL3, CCL4. CCL5, CCL6, CCL7, CCL8. CCL9/10, CCR, CCR1, CCR10, CCR10, CCR2, CCR3, CCR4, CCR5, CCR6, CCR7, CCR8, CCR9, CD1, CD2, CD3, CD3E, CD4, CD5, CD6, CD7, CD8, CD10, CD11a, CD11b, CD11c, CD13 CD14, CD15, CD16, CD18, CD19, CD20, CD21, CD22, CD23, CD25, CD27L, CD28, CD29, CD30, CD30L, CD32, CD33 (p67 proteins), CD34, CD38, CD40, CD40L, CD44, CD45, CD46, CD49a, CD52, CD54, CD55, CD56, CD61, CD64, CD66e, CD74, CD80 (B7-1), CD89, CD95, CD123, CD137, CD138, CD140a, CD146, CD147, CD148, CD152, CD164, CEACAM5, CFTR, cGMP, CINC, Clostridium botulinum toxin, Clostridium perfringens toxin, CKb8-1, CLC, CMV, CMV UL, CNTF, CNTN-1, COX, C-Ret, CRG-2, CT-1, CTACK, CTGF, CTLA-4, CX3CL1, CX3CR1, CXCL, CXCL1, CXCL2, CXCL3, CXCL4, CXCL5, CXCL6, CXCL7, CXCL8, CXCL9, CXCL10, CXCL11, CXCL12, CXCL13, CXCL14, CXCL15, CXCL16, CXCR, CXCR1, CXCR2, CXCR3, CXCR4, CXCR5, CXCR6, cytokeratin tumor-associated antigen, DAN, DCC, DcR3, DC-SIGN, Decay accelerating factor, des(1-3)-IGF-I (brain IGF-1), Dhh, digoxin, DNAM-1, Dnase, Dpp, DPPIV/CD26, Dtk, ECAD, EDA, EDA-A1, EDA-A2, EDAR, EGF, EGFR (ErbB-1), EMA, EMMPRIN, ENA, endothelin receptor, Enkephalinase, eNOS, Eot, eotaxin1, EpCAM, Ephrin B2/EphB4, EPO, ERCC, E-selectin, ET-1, Factor IIa, Factor VII, Factor VIIIc, Factor IX, fibroblast activation protein (FAP), Fas, FcR1, FEN-1, Ferritin, FGF, FGF-19, FGF-2, FGF3, FGF-8, FGFR, FGFR-3, Fibrin, FL, FLIP, Flt-3, Flt-4, Follicle stimulating hormone, Fractalkine, FZD1, FZD2, FZD3, FZD4, FZD5, FZD6, FZD7, FZD8, FZD9, FZD10, G250, Gas 6, GCP-2, GCSF, GD2, GD3, GDF, GDF-1, GDF-3 (Vgr-2), GDF-5 (BMP-14, CDMP-1), GDF-6 (BMP-13, CDMP-2), GDF-7 (BMP-12, CDMP-3), GDF-8 (Myostatin), GDF-9, GDF-15 (MIC-1), GDNF, GDNF, GFAP, GFRa-1, GFR-alpha1, GFR-alpha2, GFR-alpha3, GITR, Glucagon, Glut 4, glycoprotein IIb/IIIa (GP IIb/IIIa), GM-CSF, gp130, gp72, GRO, Growth hormone releasing factor, Hapten (NP-cap or NIP-cap), HB-EGF, HCC, HCMV gB envelope glycoprotein, HCMV) gH envelope glycoprotein, HCMV UL, Hemopoietic growth factor (HGF), Hep B gp120, heparanase, Her2, Her2/neu (ErbB-2), Her3 (ErbB-3), Her4 (ErbB-4), herpes simplex virus (HSV) gB glycoprotein, HSV gD glycoprotein, HGFA, High molecular weight melanoma-associated antigen (HMW-MAA), HIV gp120, HIV IIIB gp120 V3 loop, HLA, HLA-DR, HM1.24, HMFG PEM, HRG, Hrk, human cardiac myosin, human cytomegalovirus (HCMV), human growth hormone (HGH), HVEM, 1-309, IAP, ICAM, ICAM-1, ICAM-3, ICE, ICOS, IFNg, Ig, IgA receptor, IgE, IGF, IGF binding proteins, IGF-1R, IGFBP, IGF-I, IGF-II, IL, IL-1, IL-1R, IL-2, IL-2R, IL-4, IL-4R, IL-5, IL-5R, IL-6, IL-6R, IL-8, IL-9, IL-10, IL-12, IL-13, IL-15, IL-18, IL-18R, IL-23, interferon (INF)-alpha, INF-beta, INF-gamma, Inhibin, iNOS, Insulin A-chain, Insulin B-chain, Insulin-like growth factor 1, integrin alpha2, integrin alpha3, integrin alpha4, integrin alpha4/beta1, integrin alpha4/beta7, integrin alpha5 (alphaV), integrin alpha5/beta1, integrin alpha5/beta3, integrin alpha6, integrin beta1, integrin beta2, interferon gamma, IP-10, I-TAC, JE, Kallikrein 2, Kallikrein 5, Kallikrein 6, Kallikrein 11, Kallikrein 12, Kallikrein 14, Kallikrein 15, Kallikrein L1, Kallikrein L2, Kallikrein L3, Kallikrein L4, KC, KDR, Keratinocyte Growth Factor (KGF), laminin 5, LAMP, LAP, LAP (TGF-1), Latent TGF-1, Latent TGF-1 bp1, LBP, LDGF, LECT2, Lefty, Lewis-Y antigen, Lewis-Y related antigen, LFA-1, LFA-3, Lfo, LIF, LIGHT, lipoproteins, LIX, LKN, Lptn, L-Selectin, LT-a, LT-b, LTB4, LTBP-1, Lung surfactant, Luteinizing hormone, Lymphotoxin Beta Receptor, Mac-1, MAdCAM, MAG, MAP2, MARC, MCAM, MCAM, MCK-2, MCP, M-CSF, MDC, Mer, METALLOPROTEASES, MGDF receptor, MGMT, MHC (HLA-DR), MIF, MIG, MIP, MIP-1-alpha, MK, MMAC1, MMP, MMP-1, MMP-10, MMP-11, MMP-12, MMP-13, MMP-14, MMP-15, MMP-2, MMP-24, MMP-3, MMP-7, MMP-8, MMP-9, MPIF, Mpo, MSK, MSP, mucin (Muc1), MUC18, Muellerian-inhibitin substance, Mug, MuSK, NAIP, NAP, NCAD, N-Cadherin, NCA 90, NCAM, NCAM, Neprilysin, Neurotrophin-3, -4, or -6, Neurturin, Neuronal growth factor (NGF), NGFR, NGF-beta, nNOS, NO, NOS, Npn, NRG-3, NT, NTN, OB, OGG1, OPG, OPN, OSM, OX40L, OX40R, p150, p95, PADPr, Parathyroid hormone, PARC, PARP, PBR, PBSF, PCAD, P-Cadherin, PCNA, PDGF, PDGF, PDK-1, PECAM, PEM, PF4, PGE, PGF, PGI2, PGJ2, PIN, PLA2, placental alkaline phosphatase (FLAP), PlGF, PLP, PP14, Proinsulin, Prorelaxin, Protein C, PS, PSA, PSCA, prostate specific membrane antigen (PSMA), PTEN, PTHrp, Ptk, PTN, R51, RANK, RANKL, RANTES, RANTES, Relaxin A-chain, Relaxin B-chain, renin, respiratory syncytial virus (RSV) F, RSV Fgp, Ret, Rheumatoid factors, RLIP76, RPA2, RSK, S100, SCF/KL, SDF-1, SERINE, Serum albumin, sFRP-3, Shh, SIGIRR, SK-1, SLAM, SLPI, SMAC, SMDF, SMOH, SOD, SPARC, Stat, STEAP, STEAP-II, TACE, TACI, TAG-72 (tumor-associated glycoprotein-72), TARC, TCA-3, T-cell receptors (e.g., T-cell receptor alpha/beta), TdT, TECK, TEM1, TEM5, TEM7, TEM8, TERT, testicular PLAP-like alkaline phosphatase, TfR, TGF, TGF-alpha, TGF-beta, TGF-beta Pan Specific, TGF-beta R1 (ALK-5), TGF-beta RII, TGF-beta RIIb, TGF-beta RIII, TGF-beta1, TGF-beta2, TGF-beta3, TGF-beta4, TGF-beta5, Thrombin, Thymus Ck-1, Thyroid stimulating hormone, Tie, TIMP, TIQ, Tissue Factor, TMEFF2, Tmpo, TMPRSS2, TNF, TNF-alpha, TNF-alpha beta, TNF-beta2, TNFα, TNF-RI, TNF-RII, TNFRSF10A (TRAIL R1 Apo-2, DR4), TNFRSF10B (TRAIL R2 DR5, KILLER, TRICK-2A, TRICK-B), TNFRSF10C (TRAIL R3 DcR1, LIT, TRID), TNFRSF10D (TRAIL R4 DcR2, TRUNDD), TNFRSF11A (RANK ODF R, TRANCE R), TNFRSF11B (OPG OCIF, TR1), TNFRSF12 (TWEAK R FN14), TNFRSF13B (TACI), TNFRSF13C (BAFF R), TNFRSF14 (HVEM ATAR, HveA, LIGHT R, TR2), TNFRSF16 (NGFR p75NTR), TNFRSF17 (BCMA), TNFRSF18 (GITR AITR), TNFRSF19 (TROY TAJ, TRADE), TNFRSF19L (RELT), TNFRSF1A (TNF RI CD120a, p55-60), TNFRSF1B (TNF RII CD120b, p75-80), TNFRSF26 (TNFRH3), TNFRSF3 (LTbR TNF RUT, TNFC R), TNFRSF4 (OX40 ACT35, TXGP1 R), TNFRSF5 (CD40 p50), TNFRSF6 (Fas Apo-1, APT1, CD95), TNFRSF6B (DcR3 M68, TR6), TNFRSF7 (CD27), TNFRSF8 (CD30), TNFRSF9 (4-1BB CD137, ILA), TNFRSF21 (DR6), TNFRSF22 (DcTRAIL R2 TNFRH2), TNFRST23 (DcTRAIL R1 TNFRH1), TNFRSF25 (DR3 Apo-3, LARD, TR-3, TRAMP, WSL-1), TNFSF10 (TRAIL Apo-2 Ligand, TL2), TNFSF11 (TRANCE/RANK Ligand ODF, OPG Ligand), TNFSF12 (TWEAK Apo-3 Ligand, DR3 Ligand), TNFSF13 (APRIL TALL2), TNFSF13B (BAFF BLYS, TALL 1, THANK, TNFSF20), TNFSF14 (LIGHT HVEM Ligand, LTg), TNFSF15 (TL1A/VEGI), TNFSF18 (GITR Ligand AITR Ligand, TL6), TNFSF1A (TNF-a Conectin, DIF, TNFSF2), TNFSF1B (TNF-b LTa, TNFSF1), TNFSF3 (LTb TNFC, p33), TNFSF4 (OX40 Ligand gp34, TXGP1), TNFSF5 (CD40 Ligand CD154, gp39, HIGM1, IMD3, TRAP), TNFSF6 (Fas Ligand Apo-1 Ligand, APT1 Ligand), TNFSF7 (CD27 Ligand CD70), TNFSF8 (CD30 Ligand CD153), TNFSF9 (4-1BB Ligand CD137 Ligand), TP-1, t-PA, Tpo, TRAIL, TRAIL R, TRAIL-R1, TRAIL-R2, TRANCE, transferring receptor, TRF, Trk, TROP-2, TSG, TSLP, tumor-associated antigen CA 125, tumor-associated antigen expressing Lewis Y related carbohydrate, TWEAK, TXB2, Ung, uPAR, uPAR-1, Urokinase, VCAM, VCAM-1, VECAD, VE-Cadherin, VE-cadherin-2, VEFGR-1 (flt-1), VEGF, VEGFR, VEGFR-3 (flt-4), VEGI VIM, Viral antigens, VLA, VLA-1, VLA-4, VNR integrin, von Willebrands factor, WIF-1, WNT1, WNT2, WNT2B/13, WNT3, WNT3A, WNT4, WNT5A, WNT5B, WNT6, WNT7A, WNT7B, WNT8A, WNT8B, WNT9A, WNT9A, WNT9B, WNT10A, WNT10B, WNT11, WNT16, XCL1, XCL2, XCR1, XCR1, XEDAR, XIAP, XPD, and receptors for hormones and growth factors.
  • In some embodiments, the engineering of Fc domains described herein is done to therapeutic antibodies. A number of antibodies that are approved for use, in clinical trials, or in development may benefit from the Fc variants of the present invention. These antibodies are herein referred to as “clinical products and candidates”. Thus in a preferred embodiment, the engineered constant region(s) of the present invention may find use in a range of clinical products and candidates. For example, a number of antibodies that target CD20 may benefit from the Fc engineering of the present invention. For example the Fc variants of the present invention may find use in an antibody that is substantially similar to rituximab (Rituxan®, IDEC/Genentech/Roche) (see for example U.S. Pat. No. 5,736,137), a chimeric anti-CD20 antibody approved to treat Non-Hodgkin's lymphoma; HuMax-CD20, an anti-CD20 currently being developed by Genmab, an anti-CD20 antibody described in U.S. Pat. No. 5,500,362, AME-133 (Applied Molecular Evolution), hA20 (Immunomedics, Inc.), HumaLYM (Intracel), and PRO70769 (PCT/US2003/040426, entitled “Immunoglobulin Variants and Uses Thereof”). A number of antibodies that target members of the family of epidermal growth factor receptors, including EGFR (ErbB-1), Her2/neu (ErbB-2), Her3 (ErbB-3), Her4 (ErbB-4), may benefit from Fc engineered constant region(s) of the invention. For example the Fc engineered constant region(s) of the invention may find use in an antibody that is substantially similar to trastuzumab (Herceptin®, Genentech) (see for example U.S. Pat. No. 5,677,171), a humanized anti-Her2/neu antibody approved to treat breast cancer; pertuzumab (rhuMab-2C4, Omnitarg™), currently being developed by Genentech; an anti-Her2 antibody described in U.S. Pat. No. 4,753,894; cetuximab (Erbitux®, Imclone) (U.S. Pat. No. 4,943,533; PCT WO 96/40210), a chimeric anti-EGFR antibody in clinical trials for a variety of cancers; ABX-EGF (U.S. Pat. No. 6,235,883), currently being developed by Abgenix-Immimex-Amgen; HuMax-EGFr (U.S. Ser. No. 10/172,317), currently being developed by Genmab; 425, EMD55900, EMD62000, and EMD72000 (Merck KGaA) (U.S. Pat. No. 5,558,864; Murthy et al. 1987, Arch Biochem Biophys. 252(2):549-60; Rodeck et al., 1987, J Cell Biochem. 35(4):315-20; Kettleborough et al., 1991, Protein Eng. 4(7):773-83); ICR62 (Institute of Cancer Research) (PCT WO 95/20045; Modjtahedi et al., 1993, J. Cell Biophys. 1993, 22(1-3): 129-46; Modjtahedi et al., 1993, Br J Cancer. 1993, 67(2):247-53; Modjtahedi et al, 1996, Br J Cancer, 73(2):228-35; Modjtahedi et al, 2003, Int J Cancer, 105(2):273-80); TheraCIM hR3 (YM Biosciences, Canada and Centro de Immunologia Molecular, Cuba (U.S. Pat. No. 5,891,996; U.S. Pat. No. 6,506,883; Mateo et al, 1997, Immunotechnology, 3(1):71-81); mAb-806 (Ludwig Institute for Cancer Research, Memorial Sloan-Kettering) (Jungbluth et al. 2003, Proc Natl Acad Sci USA. 100(2):639-44); KSB-102 (KS Biomedix); MR1-1 (IVAX, National Cancer Institute) (PCT WO 0162931A2); and SC100 (Scancell) (PCT WO 01/88138). In another preferred embodiment, the Fc engineered constant region(s) of the present invention may find use in alemruzumab (Campath®, Millenium), a humanized monoclonal antibody currently approved for treatment of B-cell chronic lymphocytic leukemia. The Fc engineered constant region(s) of the present invention may find use in a variety of antibodies that are substantially similar to other clinical products and candidates, including but not limited to muromonab-CD3 (Orthoclone OKT3®), an anti-CD3 antibody developed by Ortho Biotech/Johnson & Johnson, ibritumomab tiuxetan (Zevalin®), an anti-CD20 antibody developed by IDEC/Schering AG, gemtuzumab ozogamicin (Mylotarg®), an anti-CD33 (p67 protein) antibody developed by Celltech/Wyeth, alefacept (Amevive®), an anti-LFA-3 Fc fusion developed by Biogen), abciximab (ReoPro®), developed by Centocor/Lilly, basiliximab (Simulect®), developed by Novartis, palivizumab (Synagis®), developed by MedImmune, infliximab (Remicade®), an anti-TNFalpha antibody developed by Centocor, adalimumab (Humira®), an anti-TNFalpha antibody developed by Abbott, Humicade™, an anti-TNFalpha antibody developed by Celltech, etanercept (Enbrel®), an anti-TNFalpha Fc fusion developed by Immunex/Amgen, ABX-CBL, an anti-CD147 antibody being developed by Abgenix, ABX-IL8, an anti-IL8 antibody being developed by Abgenix, ABX-MA1, an anti-MUC18 antibody being developed by Abgenix, Pemtumomab (R1549, 90Y-muHMFG1), an anti-MUC1 In development by Antisoma, Therex (R1550), an anti-MUC1 antibody being developed by Antisoma, AngioMab (A81405), being developed by Antisoma, HuBC-1, being developed by Antisoma, Thioplatin (AS1407) being developed by Antisoma, Antegren® (natalizumab), an anti-alpha-4-beta-1 (VLA-4) and alpha-4-beta-7 antibody being developed by Biogen, VLA-1 mAb, an anti-VLA-1 integrin antibody being developed by Biogen, LTBR mAb, an anti-lymphotoxin beta receptor (LTBR) antibody being developed by Biogen, CAT-152, an anti-TGF-β2 antibody being developed by Cambridge Antibody Technology, J695, an anti-IL-12 antibody being developed by Cambridge Antibody Technology and Abbott, CAT-192, an anti-TGFβ1 antibody being developed by Cambridge Antibody Technology and Genzyme, CAT-213, an anti-Eotaxin1 antibody being developed by Cambridge Antibody Technology, LymphoStat-B™ an anti-Blys antibody being developed by Cambridge Antibody Technology and Human Genome Sciences Inc., TRAIL-R1mAb, an anti-TRAIL-R1 antibody being developed by Cambridge Antibody Technology and Human Genome Sciences, Inc., Avastin™ (bevacizumab, rhuMAb-VEGF), an anti-VEGF antibody being developed by Genentech, an anti-HER receptor family antibody being developed by Genentech, Anti-Tissue Factor (ATF), an anti-Tissue Factor antibody being developed by Genentech, Xolair™ (Omalizumab), an anti-IgE antibody being developed by Genentech, Raptiva™ (Efalizumab), an anti-CD11a antibody being developed by Genentech and Xoma, MLN-02 Antibody (formerly LDP-02), being developed by Genentech and Millenium Pharmaceuticals, HuMax CD4, an anti-CD4 antibody being developed by Genmab, HuMax-IL15, an anti-11.15 antibody being developed by Genmab and Amgen, HuMax-Inflam, being developed by Genmab and Medarex, HuMax-Cancer, an anti-Heparanase I antibody being developed by Genmab and Medarex and Oxford GeoSciences, HuMax-Lymphoma, being developed by Genmab and Amgen, HuMax-TAC, being developed by Genmab, IDEC-131, and anti-CD40L antibody being developed by IDEC Pharmaceuticals, IDEC-151 (Clenoliximab), an anti-CD4 antibody being developed by IDEC Pharmaceuticals, IDEC-114, an anti-CD80 antibody being developed by IDEC Pharmaceuticals, IDEC-152, an anti-CD23 being developed by IDEC Pharmaceuticals, anti-macrophage migration factor (MIF) antibodies being developed by IDEC Pharmaceuticals, BEC2, an anti-idiotypic antibody being developed by Imclone, IMC-1C11, an anti-KDR antibody being developed by Imclone, DC101, an anti-flk-1 antibody being developed by Imclone, anti-VE cadherin antibodies being developed by Imclone, CEA-Cide™ (labetuzumab), an anti-carcinoembryonic antigen (CEA) antibody being developed by Immunomedics, LymphoCide™ (Epratuzumab), an anti-CD22 antibody being developed by Immunomedics, AFP-Cide, being developed by Immunomedics, MyelomaCide, being developed by Immunomedics, LkoCide, being developed by Immunomedics, ProstaCide, being developed by Immunomedics, MDX-010, an anti-CTLA4 antibody being developed by Medarex, MDX-060, an anti-CD30 antibody being developed by Medarex, MDX-070 being developed by Medarex, MDX-018 being developed by Medarex, Osidem™ (IDM-1), and anti-Her2 antibody being developed by Medarex and Immuno-Designed Molecules, HuMax™-CD4, an anti-CD4 antibody being developed by Medarex and Genmab, HuMax-IL15, an anti-IL15 antibody being developed by Medarex and Genmab, CNTO 148, an anti-TNFα antibody being developed by Medarex and Centocor/J&J, CNTO 1275, an anti-cytokine antibody being developed by Centocor/J&J, MOR101 and MOR102, anti-intercellular adhesion molecule-1 (ICAM-1) (CD54) antibodies being developed by MorphoSys, MOR201, an anti-fibroblast growth factor receptor 3 (FGFR-3) antibody being developed by MorphoSys, Nuvion® (visilizumab), an anti-CD3 antibody being developed by Protein Design Labs, HuZAF™, an anti-gamma interferon antibody being developed by Protein Design Labs, Anti-α5β1 Integrin, being developed by Protein Design Labs, anti-IL-12, being developed by Protein Design Labs, ING-1, an anti-Ep-CAM antibody being developed by Xoma, and MLN01, an anti-Beta2 integrin antibody being developed by Xoma, an pI-ADC antibody being developed by Seattle Genetics, all of the above-cited references in this paragraph are expressly incorporated herein by reference.
  • The carboxy-terminal portion of each chain defines a constant region primarily responsible for effector function. Kabat et al. collected numerous primary sequences of the variable regions of heavy chains and light chains. Based on the degree of conservation of the sequences, they classified individual primary sequences into the CDR and the framework and made a list thereof (see SEQUENCES OF IMMUNOLOGICAL INTEREST, 5th edition, NIH publication, No. 91-3242, E. A. Kabat et al., entirely incorporated by reference).
  • In the IgG subclass of immunoglobulins, there are several immunoglobulin domains in the heavy chain. By “immunoglobulin (Ig) domain” herein is meant a region of an immunoglobulin having a distinct tertiary structure. Of interest in the present invention are the heavy chain domains, including, the constant heavy (CH) domains and the hinge domains. In the context of IgG antibodies, the IgG isotypes each have three CH regions. Accordingly, “CH” domains in the context of IgG are as follows: “CH1” refers to positions 118-220 according to the EU index as in Kabat. “CH2” refers to positions 237-340 according to the EU index as in Kabat, and “CH3” refers to positions 341-447 according to the EU index as in Kabat. As shown herein and described below, the variants of the present invention can include substitutions in one or more of the CH regions, as well as the hinge region, discussed below.
  • It should be noted that the sequences depicted herein start at the CH1 region, position 118; the variable regions are not included except as noted. For example, the first amino acid of SEQ ID NO: 2, while designated as position “1” in the sequence listing, corresponds to position 118 of the CH1 region, according to EU numbering.
  • Another type of Ig domain of the heavy chain is the hinge region. By “hinge” or “hinge region” or “antibody hinge region” or “immunoglobulin hinge region” herein is meant the flexible polypeptide comprising the amino acids between the first and second constant domains of an antibody. Structurally, the IgG CH1 domain ends at EU position 220, and the IgG CH2 domain begins at residue EU position 237. Thus for IgG the antibody hinge is herein defined to include positions 221 (D221 in IgG1) to 236 (G236 in IgG1), wherein the numbering is according to the EU index as in Kabat. In some embodiments, for example in the context of an Fc region, the lower hinge is included, with the “lower hinge” generally referring to positions 226 or 230. As noted herein, Fc variant variants can be made in the hinge region as well.
  • The light chain generally comprises two domains, the variable light domain (containing the light chain CDRs and together with the variable heavy domains forming the Fv region), and a constant light chain region (often referred to as CL or Cκ).
  • Another region of interest for additional substitutions, outlined below, is the Fc region. By “Fc” or “Fc region” or “Fc domain” as used herein is meant the polypeptide comprising the constant region of an antibody excluding the first constant region immunoglobulin domain and in some cases, part of the hinge. Thus Fc refers to the last two constant region immunoglobulin domains of IgA, IgD, and IgG, the last three constant region immunoglobulin domains of IgE and IgM, and the flexible hinge N-terminal to these domains. For IgA and IgM, Fc may include the J chain. For IgG, the Fc domain comprises immunoglobulin domains Cγ2 and Cγ3 (Cγ2 and Cγ3) and the lower hinge region between Cγ1 (Cγ1) and Cγ2 (Cγ2). Although the boundaries of the Fc region may vary, the human IgG heavy chain Fc region is usually defined to include residues C226 or P230 to its carboxyl-terminus, wherein the numbering is according to the EU index as in Kabat. In some embodiments, as is more fully described below, amino acid modifications are made to the Fc region, for example to alter binding to one or more FcγR receptors or to the FcRn receptor.
  • In some embodiments, the antibodies are full length. By “full length antibody” herein is meant the structure that constitutes the natural biological form of an antibody, including variable and constant regions, including one or more modifications as outlined herein.
  • Alternatively, the antibodies can be a variety of structures, including, but not limited to, antibody fragments, monoclonal antibodies, bispecific antibodies, minibodies, domain antibodies, synthetic antibodies (sometimes referred to herein as “antibody mimetics”), chimeric antibodies, humanized antibodies, antibody fusions (sometimes referred to as “antibody conjugates”), and fragments of each, respectively.
  • In one embodiment, the antibody is an antibody fragment, as long as it contains at least one constant domain which can be engineered. Specific antibody fragments include, but are not limited to, (i) the Fab fragment consisting of VL, VH, CL and CH1 domains, (ii) the Fd fragment consisting of the VH and CH1 domains, (iii) F(ab′)2 fragments, a bivalent fragment comprising two linked Fab fragments (vii) single chain Fv molecules (scFv), wherein a. VH domain and a VL domain are linked by a peptide linker which allows the two domains to associate to form an antigen binding site (Bird et al., 1988, Science 242:423-426, Huston et al., 1988, Proc. Natl. Acad. Sci. U.S.A. 85:5879-5883, entirely incorporated by reference), (iv) “diabodies” or “triabodies”, multivalent or multispecific fragments constructed by gene fusion (Tomlinson et. al., 2000, Methods Enzymol. 326:461-479; WO94/13804; Holliger et al., 1993, Proc. Natl. Acad. Sci. U.S.A. 90:6444-6448, all entirely incorporated by reference).
  • Other antibody fragments that can be used include fragments that contain one or more of the CH1, CH2, CH3, hinge and CL domains of the invention that have been engineered. For example, Fc fusions are fusions of the Fc region (CH2 and CH3, optionally with the hinge region) fused to another protein. A number of Fc fusions are known the art and can be improved by the addition of the variants of the invention. In the present case, antibody fusions can be made comprising CH1; CH1, CH2 and CH3; CH2; CH3; CH2 and CH3; CH1 and CH3, any or all of which can be made optionally with the hinge region, utilizing any combination of Fc variants described herein.
    • B. Chimeric and Humanized Antibodies
  • In some embodiments, the antibody can be a mixture from different species, e.g. a chimeric antibody and/or a humanized antibody. In general, both “chimeric antibodies” and “humanized antibodies” refer to antibodies that combine regions from more than one species. For example, “chimeric antibodies” traditionally comprise variable region(s) from a mouse (or rat, in some cases) and the constant region(s) from a human. “Humanized antibodies” generally refer to non-human antibodies that have had the variable-domain framework regions swapped for sequences found in human antibodies. Generally, in a humanized antibody, the entire antibody, except the CDRs, is encoded by a polynucleotide of human origin or is identical to such an antibody except within its CDRs. The CDRs, some or all of which are encoded by nucleic acids originating in a non-human organism, are grafted into the beta-sheet framework of a human antibody variable region to create an antibody, the specificity of which is determined by the engrafted CDRs. The creation of such antibodies is described in, e.g., WO 92/11018, Jones, 1986, Nature 321:522-525, Verhoeyen et al., 1988, Science 239:1534-1536, all entirely incorporated by reference. “Backmutation” of selected acceptor framework residues to the corresponding donor residues is often required to regain affinity that is lost in the initial grafted construct (U.S. Pat. No. 5,530,101; U.S. Pat. No. 5,585,089; U.S. Pat. No. 5,693,761; U.S. Pat. No. 5,693,762; U.S. Pat. No. 6,180,370; U.S. Pat. No. 5,859,205; U.S. Pat. No. 5,821,337; U.S. Pat. No. 6,054,297; U.S. Pat. No. 6,407,213, all entirely incorporated by reference). The humanized antibody optimally also will comprise at least a portion of an immunoglobulin constant region, typically that of a human immunoglobulin, and thus will typically comprise a human Fc region. Humanized antibodies can also be generated using mice with a genetically engineered immune system, Roque et al., 2004, Biotechnol. Prog. 20:639-654, entirely incorporated by reference. A variety of techniques and methods for humanizing and reshaping non-human antibodies are well known in the art (See Tsurushita & Vasquez, 2004, Humanization of Monoclonal Antibodies, Molecular Biology of B Cells, 533-545, Elsevier Science (USA), and references cited therein, all entirely incorporated by reference), Humanization methods include but are not limited to methods described in Jones et al., 1986, Nature 321:522-525; Riechmann et al., 1988; Nature 332:323-329; Verhoeyen et al., 1988, Science, 239:1534-1536; Queen et al., 1989, Proc Natl Acad Sci, USA 86:10029-33; He et al., 1998, J. Immunol. 160: 1029-1035; Carter et al., 1992, Proc Natl Acad Sci USA 89:4285-9, Presta et al., 1997, Cancer Res. 57(20):4593-9; Gorman et al., 1991, Proc. Natl. Acad. Sci. USA 88:4181-4185; O'Connor et al., 1998, Protein Eng 11:321-8, all entirely incorporated by reference, Humanization or other methods of reducing the immunogenicity of nonhuman antibody variable regions may include resurfacing methods, as described for example in Roguska et al., 1994, Proc. Natl. Acad. Sci. USA 91:969-973, entirely incorporated by reference. In one embodiment, the parent antibody has been affinity matured, as is known in the art. Structure-based methods may be employed for humanization and affinity maturation, for example as described in U.S. Ser. No. 11/004,590. Selection based methods may be employed to humanize and/or affinity mature antibody variable regions, including but not limited to methods described in Wu et al., 1999, J. Mol. Biol. 294:151-162; Baca et al., 1997, J. Biol. Chem. 272(16): 10678-10684; Rosok et al., 1996, J. Biol. Chem. 271(37): 22611-22618; Rader et al., 1998, Proc. Natl. Acad. Sci. USA 95: 8910-8915; Krauss et al., 2003, Protein Engineering 16(10):753-759, all entirely incorporated by reference. Other humanization methods may involve the grafting of only parts of the CDRs, including but not limited to methods described in U.S. Ser. No. 09/810,510; Tan et al., 2002, J. Immunol. 169:1119-1125; De Pascalis et al., 2002, J. Immunol. 169:3076-3084, all entirely incorporated by reference.
  • In one embodiment, the antibodies of the invention can be multispecific antibodies, and notably bispecific antibodies, also sometimes referred to as “diabodies”. These are antibodies that bind to two (or more) different antigens, or different epitopes on the same antigen. Diabodies can be manufactured in a variety of ways known in the art (Holliger and Winter, 1993, Current Opinion Biotechnol. 4:446-449, entirely incorporated by reference), e.g., prepared chemically or from hybrid hybridomas. In some cases, multispecific (for example bispecific) antibodies are not preferred.
  • In one embodiment, the antibody is a minibody. Minibodies are minimized antibody-like proteins comprising a scFv joined to a CH3 domain. Hu et al., 1996, Cancer Res. 56:3055-3061, entirely incorporated by reference. In the present instance, the CH3 domain can be engineered to improve binding to FcRn and/or increase in vivo serum half-life. In some cases, the scFv can be joined to the Fc region, and may include some or the entire hinge region.
  • 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.
  • “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.
  • 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 10−10M, 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.
  • 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.
    • C. Fc Variants
  • The present invention relates to the generation of Fc variants of antibodies. As discussed above, by “Fc” or “Fc region” or “Fc domain” as used herein is meant the polypeptide comprising the constant region of an antibody excluding the first constant region immunoglobulin domain and in some cases, part of the hinge. Thus Fc refers to the last two constant region immunoglobulin domains of IgA, IgD, and IgG, the last three constant region immunoglobulin domains of IgE and IgM, and the flexible hinge N-terminal to these domains. For IgA and IgM, Fc may include the J chain. For IgG, the Fc domain comprises immunoglobulin domains Cγ2 and Cγ3 (Cγ2 and Cγ3) and the lower hinge region between Cγ1 (Cγ1) and Cγ2 (Cγ2). Although the boundaries of the Fc region may vary, the human IgG heavy chain Fc region is usually defined to include residues C226 or P230 to its carboxyl-terminus, wherein the numbering is according to the EU index as in Kabat. In some embodiments, as is more fully described below, amino acid modifications are made to the Fc region, for example to alter binding to one or more FcγR receptors or to the FcRn receptor.
  • The present invention relates to the generation of Fc variants of antibodies to form “Fc variant antibodies”. Fc variants are made by introducing amino acid mutations into the parent molecule. “Mutations” in this context are usually amino acid substitutions, although as shown herein, deletions and insertions of amino acids can also be done and thus are defined as mutations.
  • The Fc variant antibodies of the invention show increased binding to FcRn and/or increased in vivo serum half-life. By “FcRn” or “neonatal Fc Receptor” as used herein is meant a protein that binds the IgG antibody Fc region and is encoded at least in part by an FcRn gene. The FcRn may be from any organism, including but not limited to humans, mice, rats, rabbits, and monkeys. As is known in the art, the functional FcRn protein comprises two polypeptides, often referred to as the heavy chain and light chain. The light chain is beta-2-microglobulin and the heavy chain is encoded by the FcRn gene. Unless other wise noted herein, FcRn or an FcRn protein refers to the complex of FcRn heavy chain with beta-2-microglobulin. In some cases, the FcRn variants bind to the human FcRn receptor, or it may be desirable to design variants that bind to rodent or primate receptors in addition, to facilitate clinical trials.
  • A variety of such substitutions are known and described in U.S. Ser. Nos. 12/341,769; 10/672,280; 10/822,231; 11/124,620; 11/174,287; 11/396,495; 11/538,406; 11/538,411; and 12/020,443, each of which is incorporated herein by reference in its entirety for all purposes and in particular for all outlined substitutions.
  • In some embodiments, an Fc variant antibody can be engineered to include any of the following substitutions, alone or in any combination; 436I, 436V, 311I, 311V, 428L, 434S, 428L/434S, 259I, 308F, 259I/308F, 259I/308F/428L, 307Q/434S, 434A, 434H, 250Q/428L, M252Y/S254T/T256E, 307Q/434A, 307Q//380A/434A, and 308P/434A, 311I/434S, 311V/434S, 434S/436I, 434S/436V. Numbering is EU as in Kabat, and it is understood that the substitution is non-native to the starting molecule. As has been shown previously, these FcRn substitutions work in IgG1, IgG2 and IgG1/G2 hybrid backbones, and are specifically included for IgG3 and IgG4 backbones and derivatives of any IgG isoform as well.
  • In further embodiments, an Fc variant antibody can be engineered to include any of the following substitutions, alone or in any combination: 248Y, 249G, 253H, 253N, 253L, 253T, 253V, 253Q, 253M, 253Y, 253F, 253W, 255H, 255I, 255Q, 255E, 255F, 255L, 255S, 255G, 255W, 255P, 284D, 284E, 285D, 285E, 286Q, 286F, 286D, 286E, 286G, 286L, 286P, 286Y, 286W, 2861, 286V, 286R, 286K, 286H, 288N, 288H, 288Q, 288Y, 288F, 288W, 288L, 288I, 307M, 307E, 307R, 307D, 307G, 3071, 307N, 307P, 307Q, 307S, 307V, 307Y, 307K, 307H, 307L, 307F, 307W, 309W, 309R, 309K, 309D, 309E, 309F, 309H, 309I, 309P, 309Q, 309L, 309Y, 309M, 312E, 312R, 312K, 312Y, 338R, 338H, 378S, 378V, 378G, 426W, 426H, 426L, 426V, 426Y, 426M, 426I, 426F, 426T, 428I, 428V, 433G, 436F, 438W, 4381T, 438N, 438S, 438G, 438Y, 438F, 4381, 438D, 436I, 436V, and 436W, where the numbering is according to the EU Index as in Kabat, and it is understood that the substitution is non-native to the starting molecule. As has been shown previously, these FcRn substitutions work in IgG1, IgG2 and IgG1/G2 hybrid backbones, and are specifically included for IgG3 and IgG4 backbones and derivatives of any IgG isoform as well.
  • In some embodiments, the Fc variant of the invention includes at least two modifications, wherein one of said modifications is the substitution N434S, and the other of said modifications is a substitution selected from one or more of the following: 248Y, 249G, 253H, 253N, 253L, 253T, 253V, 253Q, 253M, 253Y, 253F, 253W, 255H, 255I, 255Q, 255E, 255F, 255L, 255S, 255G, 255W, 255P, 284D, 284E, 285D, 285E, 286Q, 286F, 286D, 286E, 286G, 286L, 286P, 286Y, 286W, 286I, 286V, 286R, 286K, 286H, 288N, 288H, 288Q, 288Y, 288F, 288W, 288L, 288I, 307M, 307E, 307R, 307D, 307G, 307I, 307N, 307P, 307Q, 307S, 307V, 307Y, 307K, 307H, 307L, 307F, 307W, 309W, 309R, 309K, 309D, 309E, 309F, 309H, 309I, 309P, 309Q, 309L, 309Y, 309M, 312E, 312R, 312K, 312Y, 338R, 338H, 378S, 378V, 378G, 426W, 426H, 426L, 426V, 426Y, 426M, 426I, 426F, 426T, 428I, 428V, 433G, 436F, 438W, 438H, 438N, 438S, 438G, 438Y, 438F, 438I, 438D, 436I, 436V, and 436W, where the numbering is according to the EU Index as in Kabat, and it is understood that the substitution is non-native to the starting molecule. As has been shown previously, these FcRn substitutions work in IgG1, IgG2 and IgG1/G2 hybrid backbones, and are specifically included for IgG3 and IgG4 backbones and derivatives of any IgG isoform as well.
  • In some embodiments, an Fc variant antibody can be engineered to include any of the following substitutions, alone or in any combination: 378T, 378E, 378I, 378L, 378M, 426G, 426A, 426Q, 426P, 426K, and 426R, where the numbering is according to the EU Index as in Kabat, and it is understood that the substitution is non-native to the starting molecule. As has been shown previously, these FcRn substitutions work in IgG1, IgG2 and IgG1/G2 hybrid backbones, and are specifically included for IgG3 and IgG4 backbones and derivatives of any IgG isoform as well.
  • In some embodiments, an Fc variant antibody can be engineered to include any of the substitutions in any of the following positions alone or in any combination: 307, 311, 378, 426, 428, 434, and 4.36. In further embodiments, the substitutions are as follows, again alone or in any combination: 307Q, 308P, 311I, 311V, 378E, 378F, 3781, 378L, 378M, 378R, 378T, 378V, 378Y, 426A, 426G, 426K, 426L, 426P, 426Q, 426R, 426V, 428L, 434S, 436I, and 436V. In still further embodiments, the Fc variant antibody is engineered to include any of the of the following substitutions, alone or in any combination of the following or with any other of the substitutions discussed herein: T307Q/N434S/Q311I, T307Q/N434S/Q311V, T307Q/N434S/A378V, T307Q/N434S/S426V, T307Q/N434S/Y436I, T307Q/N434S/Y436V, Q311I/N434S/A378V, Q311I/N434S/A378T, Q311I/N434S/A378I, Q311I/N434S/A378L, Q311I/N434S/S426V, Q311I/N434S/Y436L Q311I/N434S/Y436V, Q311V/S426V, Q311I/Y436I, Q311I/Y436V, Q311I/S426V/Y436I, Q311V/S426V/Y436V, Q311V/N434S/A378V, Q311V/N434S/S426V, Q311V/N434S/Y436I, Q311V/N434S/Y436V, S426V/N434S/A378V, S426V/N434S/A378T, S426V/N434S/A378I, S426V/N434S/A378L, S426V/N434S/Y436I, S426V/N434S/Y436V, N434S/Y436I/A378V, N434S/Y436I/A378T, N434S/Y436I/A378I, N434S/Y436I/A378L, N434S/Y436V/A378V, N434S/Y436V/A378T, N434S/Y436V/A378I, N434S/Y436V/A378L, N434S/Y436V/S426G, N434S/Y436V/S426A, N434S/Y436V/S426Q, N434S/Y436V/S426P, N434S/Y436V7S426L, M428L/N434S/T307Q, M428L/N434S/Q311I, M428L/N434S/Q311V, M428L/N434S/A378V, M428L/N434S/S426V, M428L/N434S/Y436I, M428L/N434S/Y436V, V308P/N434S, A37817N434S, A378I/N434S, A378L/N434S, A378E/N434S, A378M/N434S, A378F/N434S, A378Y/N434S, A378R/N434S, S426G/N434S, S426A/N434S, S426P/N434S, S426Q/N434S, S426K/N434S, S426R/N434S, T307Q/Q311I, and T307Q/Q311V, where the numbering is according to the EU Index as in Kabat, and it is understood that the substitution is non-native to the starting molecule. As has been shown previously, these FcRn substitutions work in IgG1, IgG2 and IgG1/G2 hybrid backbones, and are specifically included for IgG3 and IgG4 backbones and derivatives of any IgG isoform as well.
  • In some embodiments, an Fc variant antibody can be engineered to include at least two of the following substitutions, alone or in any combination: 248Y, 249G, 253H, 253N, 253L, 253T, 253V, 253Q, 253M, 253Y, 253F, 253W, 255H, 255I, 255Q, 255E, 255F, 255L, 255S, 255G, 255W, 255P, 284D, 284E, 285D, 285E, 286Q, 286F, 286D, 286E, 286G, 286L, 286P, 286Y, 286W, 286I, 286V, 286R, 286K, 286H, 288N, 288H, 288Q, 288Y, 288F, 288W, 288L, 288I, 307M, 307E, 307R, 307D, 307G, 307I, 307N, 307P, 307Q, 307S, 307V, 307Y, 307K, 307H, 307L, 307F, 307W, 309W, 309R, 309K, 309D, 309E, 309F, 309H, 309I, 309P, 309Q, 309L, 309Y, 309M, 312E, 312R, 312K, 312Y, 338R, 338H, 378S, 378V, 378G, 426W, 426H, 426L, 426V, 426Y, 426M, 426I, 426F, 426T, 428I, 428V, 433G, 436F, 438W, 438H, 438N, 438S, 438G, 438Y, 438F, 438I, 438D, 436I, 436V, and 436W, where the numbering is according to the EU Index as in Kabat, and it is understood that the substitution is non-native to the starting molecule. As has been shown previously, these FcRn substitutions work in IgG1, IgG2 and IgG1/G2 hybrid backbones, and are specifically included for IgG3 and IgG4 backbones and derivatives of any IgG isoform as well.
  • In other embodiments, no Fc variants are made in the variable region(s) of the antibodies. This is to be distinguished from affinity maturation substitutions in the variable region(s) that are made to increase binding affinity of the antibody to its antigen. That is, an Fc variant in the variable region(s) is generally significantly “silent” with respect to binding affinity.
    • III. Other Amino Acid Substitutions
  • As will be appreciated by those in the art, the Fc variant antibodies of the invention can contain additional amino acid substitutions in addition to the substitutions discussed above.
  • In some embodiments, amino acid substitutions are imported from one isotype into the Fc variant antibody.
  • In the hinge region (positions 233-236), changes can be made to increase effector function. That is, IgG2 has lowered effector function, and as a result, amino acid substitutions at these positions from PVA(deletion) can be changed to ELLG, and an additional G327A variant generated as well.
  • In the CH3 region, a mutation at position 384 can be made, for example substituting a non-native serine.
  • Additional mutations that can be made include adding either N-terminal or C-terminal (depending on the structure of the antibody or fusion protein) “tails” or sequences of one or more Fc amino acids; for example, glutamic acids and aspartic acids can be added to the CH3 O-terminus; generally, from 1 to 5 amino acids are added.
    • Properties of the Fc Variant Antibodies of the Invention
  • The Fc variant antibodies of the invention display increased binding to FcRn and/or increased in vivo serum half-life.
  • In addition, some variants herein are generated to increase stability. As noted herein, a number of properties of antibodies affect the clearance rate (e.g. stability for half-life) in vivo. In addition to antibody binding to the FcRn receptor, other factors that contribute to clearance and half-life are serum aggregation, enzymatic degradation in the serum, inherent immunogenicity of the antibody leading to clearing by the immune system, antigen-mediated uptake, FcR (non-FcRn) mediated uptake and non-serum distribution (e.g. in different tissue compartments).
    • IV. Optional and Additional Fc Engineering Fc Engineering
  • In addition to substitutions made to increase binding affinity to FcRn and/or increase serum half life, other substitutions can be made in the Fc region, in general for altering binding to FcγR receptors.
  • By “Fc gamma receptor”, “FcγR” or “FcgammaR” as used herein is meant any member of the family of proteins that bind the IgG antibody Fc region and is encoded by an FcγR gene. In humans this family includes but is not limited to FcγRI (CD64), including isoforms FcγRIa, FcγRIb, and FcγRIc; FcγRII (CD32), including isoforms FcγRIIa (including allotypes H131 and R131), FcγRIIb (including FcγRIIb-1 and FcγRIIb-2), and FcγRIIc; and FcγRIII (CD16), including isoforms FcγRIIIa (including allotypes V158 and F158) and FcγRIIIb (including allotypes FcγRIIIb-NA1 and FcγRIIIb-NA2) (Jefferis et al., 2002, Immunol Lett 82:57-65, entirely incorporated by reference), as well as any undiscovered human FcγRs or FcγR isoforms or allotypes. An FcγR may be from any organism, including but not limited to humans, mice, rats, rabbits, and monkeys. Mouse FcγRs include but are not limited to FcγRI (CD64), FcγRII (CD32), FcγRIII-1 (CD16), and FcγRIII-2 (CD16-2), as well as any undiscovered mouse FcγRs or FcγR isoforms or allotypes.
  • There are a number of useful Fc substitutions that can be made to alter binding to one or more of the FcγR receptors. Substitutions that result in increased binding as well as decreased binding can be useful. For example, it is known that increased binding to FcγRIIIa generally results in increased ADCC (antibody dependent cell-mediated cytotoxicity; the cell-mediated reaction wherein nonspecific cytotoxic cells that express FcγRs recognize bound antibody on a target cell and subsequently cause lysis of the target cell. Similarly, decreased binding to FcγRIIb (an inhibitory receptor) can be beneficial as well in some circumstances. Amino acid substitutions that find use in the present invention include those listed in U.S. Ser. No. 11/124,620 (particularly FIG. 41), U.S. Ser. Nos. 11/174,287, 11/396,495, 11/538,406, all of which are expressly incorporated herein by reference in their entirety and specifically for the variants disclosed therein. Particular variants that find use include, but are not limited to, 236A, 239D, 239E, 332E, 332D, 239D/332E, 267D, 267E, 328F, 267E/328F, 236A/332E, 239D/332E/330Y, 239D, 332E/330L and 299T.
    • V. Other Antibody Modifications
  • In addition to substitutions made to increase binding affinity to FcRn and/or increase in vivo serum half life, additional antibody modifications can be made, as described in further detail below.
    • Affinity Maturation
  • In some embodiments, one or more amino acid modifications are made in one or more of the CDRs of the antibody. In general, only 1 or 2 or 3-amino acids are substituted in any single CDR, and generally no more than from 4, 5, 6, 7, 8 9 or 10 changes are made within a set of CDRs. However, it should be appreciated that any combination of no substitutions, 1, 2 or 3 substitutions in any CDR can be independently and optionally combined with any other substitution.
  • In some cases, amino acid modifications in the CDRs are referred to as “affinity maturation”. An “affinity matured” antibody is one having one or more alteration(s) in one or more CDRs which results in an improvement in the affinity of the antibody for antigen, compared to a parent antibody which does not possess those alteration(s). In some cases, although rare, it may be desirable to decrease the affinity of an antibody to its antigen, but this is generally not preferred.
  • Affinity maturation can be done to increase the binding affinity of the antibody for the antigen by at least about 10% to 50-100-150% or more, or from 1 to 5 fold as compared to the “parent” antibody. Preferred affinity matured antibodies will have nanomolar or even picomolar affinities for the target antigen. Affinity matured antibodies are produced by known procedures. See, for example, Marks et al., 1992, Biotechnology 10:779-783 that describes affinity maturation by variable heavy chain (VH) and variable light chain (VL) domain shuffling. Random mutagenesis of CDR and/or framework residues is described in: Barbas, et al. 1994, Proc. Nat, Acad. Sci, USA 91:3809-3813; Shier et al., 1995, Gene 169:147-155; Yelton et al., 1995, J. Immunol. 155:1994-2004; Jackson et al., 1995, J. Immunol. 154(7):3310-9; and Hawkins et al., 1992, J. Mol. Biol. 226:889-896, for example.
  • Alternatively, amino acid modifications can be made in one or more of the CDRs of the antibodies of the invention that are “silent”, e.g. that do not significantly alter the affinity of the antibody for the antigen. These can be made for a number of reasons, including optimizing expression (as can be done for the nucleic acids encoding the antibodies of the invention).
  • Thus, included within the definition of the CDRs and antibodies of the invention are variant CDRs and antibodies; that is, the antibodies of the invention can include amino acid modifications in one or more of the CDRs of Ab79 and Ab19. In addition, as outlined below, amino acid modifications can also independently and optionally be made in any region outside the CDRs, including framework and constant regions.
    • ADC Modifications
  • In some embodiments, the Fc variant antibodies of the invention are conjugated with drugs to form antibody-drug conjugates (ADCs). In general, ADCs are used in oncology applications, where the use of antibody-drug conjugates for the local delivery of cytotoxic or cytostatic agents allows for the targeted delivery of the drug moiety to tumors, which can allow higher efficacy, lower toxicity, etc. An overview of this technology is provided in Ducry et al., Bioconjugate Chem., 21:5-13 (2010), Carter et al., Cancer J. 14(3):154 (2008) and Senter, Current Opin. Chem. Biol. 13:235-244 (2009), all of which are hereby incorporated by reference in their entirety
  • Thus the invention provides Fc variant antibodies conjugated to drugs. Generally, conjugation is done by covalent attachment to the antibody, as further described below, and generally relies on a linker, often a peptide linkage (which, as described below, may be designed to be sensitive to cleavage by proteases at the target site or not). In addition, as described above, linkage of the linker-drug unit (LU-D) can be done by attachment to cysteines within the antibody. As will be appreciated by those in the art, the number of drug moieties per antibody can change, depending on the conditions of the reaction, and can vary from 1:1 to 10:1 drug:antibody. As will be appreciated by those in the art, the actual number is an average.
  • Thus the invention provides Fc variant antibodies conjugated to drugs. As described below, the drug of the ADC can be any number of agents, including but not limited to cytotoxic agents such as chemotherapeutic agents, growth inhibitory agents, toxins (for example, an enzymatically active toxin of bacterial, fungal, plant, or animal origin, or fragments thereof), or a radioactive isotope (that is, a radioconjugate) are provided. In other embodiments, the invention further provides methods of using the ADCs.
  • Drugs for use in the present invention include cytotoxic drugs, particularly those which are used for cancer therapy. Such drugs include, in general, DNA damaging agents, anti-metabolites, natural products and their analogs. Exemplary classes of cytotoxic agents include the enzyme inhibitors such as dihydrofolate reductase inhibitors, and thymidylate synthase inhibitors, DNA intercalators, DNA cleavers, topoisomerase inhibitors, the anthracycline family of drugs, the vinca drugs, the mitomycins, the bleomycins, the cytotoxic nucleosides, the pteridine family of drugs, diynenes, the podophyllotoxins, dolastatins, maytansinoids, differentiation inducers, and taxols.
  • Members of these classes include, for example, methotrexate, methopterin, dichloromethotrexate, 5-fluorouracil, 6-mercaptopurine, cytosine arabinoside, melphalan, leurosine, leurosideine, actinomycin, daunorubicin, doxorubicin, mitomycin C, mitomycin A, caminomycin, aminopterin, tallysomycin, podophyllotoxin and podophyllotoxin derivatives such as etoposide or etoposide phosphate, vinblastine, vincristine, vindesine, taxanes including taxol, taxotere retinoic acid, butyric acid, N8-acetyl spermidine, camptothecin, calicheamicin, esperamicin, ene-diynes, duocarmycin A, duocarmycin SA, calicheamicin, camptothecin, maytansinoids (including DM1), monomethylauristatin E (MMAE), monomethylauristatin F (MMAF), and maytansinoids (DM4) and their analogues.
  • Toxins may be used as antibody-toxin conjugates and include bacterial toxins such as diphtheria toxin, plant toxins such as ricin, small molecule toxins such as geldanamycin (Mandler et al (2000) J. Nat, Cancer Inst. 92(19): 1573-1581; Mandler et al (2000) Bioorganic & Med. Chem. Letters 10:1025-1028; Mandler et al (2002) Bioconjugate Chem. 13:786-791), maytansinoids (EP 1391213; Liu et al., (1996) Proc. Natl. Acad. Sci. USA 93:8618-862.3), and calicheamicin (Lode et al (1998) Cancer Res. 58:2928; Hinman et al (1993) Cancer Res. 53:3336-3342). Toxins may exert their cytotoxic and cytostatic effects by mechanisms including tubulin binding, DNA binding, or topoisomerase inhibition.
  • Conjugates of an Fc variant antibody and one or more small molecule toxins,
  • such as a maytansinoids, dolastatins, auristatins, a trichothecene, calicheamicin, and CC1065, and the derivatives of these toxins that have toxin activity, are contemplated.
  • Maytansinoids
  • Maytansine compounds suitable for use as maytansinoid drug moieties are well known in the art, and can be isolated from natural sources according to known methods, produced using genetic engineering techniques (see Yu et al (2002) PNAS 99:7968-7973), or maytansinol and maytansinol analogues prepared synthetically according to known methods. As described below, drugs may be modified by the incorporation of a functionally active group such as a thiol or amine group for conjugation to the antibody.
  • Exemplary maytansinoid drug moieties include those having a modified aromatic ring, such as: C-19-dechloro (U.S. Pat. No. 4,256,746) (prepared by lithium aluminum hydride reduction of ansamytocin P2); C-20-hydroxy (or C-20-demethyl)+/−C-19-dechloro (U.S. Pat. Nos. 4,361,650 and 4,307,016) (prepared by demethylation using Streptomyces or Actinomyces or dechlorination using LAH); and C-20-demethoxy, C-20-acyloxy (—OCOR), +/−dechloro (U.S. Pat. No. 4,294,757) (prepared by acylation using acyl chlorides) and those having modifications at other positions
  • Exemplary maytansinoid drag moieties also include those having modifications such as: C-9-SH (U.S. Pat. No. 4,424,219) (prepared by the reaction of maytansinol with H2S or P2S5); C-14-alkoxymethyl(demethoxy/CH2OR) (U.S. Pat. No. 4,331,598); C-14-hydroxymethyl or acyloxymethyl (CH2OH or CH2OAc) (U.S. Pat. No. 4,450,254) prepared from Nocardia); C-15-hydroxy/acyloxy (U.S. Pat. No. 4,364,866) (prepared by the conversion of maytansinol by Streptomyces); C-15-methoxy (U.S. Pat. Nos. 4,313,946 and 4,315,929) (isolated from Trewia nudlflora); C-18-N-demethyl (U.S. Pat. Nos. 4,362,663 and 4,322,348) (prepared by the demethylation of maytansinol by Streptomyces); and 4,5-deoxy (U.S. Pat. No. 4,371,533) (prepared by the titanium trichloride/LAH reduction of maytansinol).
  • Of particular use are DM1 (disclosed in U.S. Pat. No. 5,208,020, incorporated by reference) and DM4 (disclosed in U.S. Pat. No. 7,276,497, incorporated by reference). See also a number of additional maytansinoid derivatives and methods in 5,416,064, WO/01/24763, 7,303,749, 7,601,354, U.S. Ser. No. 12/631,508, WO02/098883, 6,441,163, 7,368,565, WO02/16368 and WO04/1033272, all of which are expressly incorporated by reference in their entirety.
  • ADC's containing maytansinoids, methods of making same, and their therapeutic use are disclosed, for example, in U.S. Pat. Nos. 5,208,020; 5,416,064; 6,441,163 and European Patent EP 0 425 235 B1, the disclosures of which are hereby expressly incorporated by reference, Liu et al., Proc. Natl. Acad, Sci. USA 93:8618-8623 (1996) described ADCs comprising a maytansinoid designated DM1 linked to the monoclonal antibody C242 directed against human colorectal cancer. The conjugate was found to be highly cytotoxic towards cultured colon cancer cells, and showed antitumor activity in an in vivo tumor growth assay.
  • Chari et al., Cancer Research 52:127-131 (1992) describe ADCs in which a maytansinoid was conjugated via a disulfide linker to the murine antibody A7 binding to an antigen on human colon cancer cell lines, or to another murine monoclonal antibody TA. 1 that binds the HER-2/neu oncogene. The cytotoxicity of the TA.1-maytansonoid conjugate was tested in vitro on the human breast cancer cell line SK-BR-3, which expresses 3×105 HER-2 surface antigens per cell. The drug conjugate achieved a degree of cytotoxicity similar to the free maytansinoid drug, which could be increased by increasing the number of maytansinoid molecules per antibody molecule. The A7-maytansinoid conjugate showed low systemic cytotoxicity in mice.
  • Auristatins and Dolastatins
  • In some embodiments, the ADC comprises an Fc variant antibody conjugated to dolastatins or dolostatin peptidic analogs and derivatives, the auristatins (U.S. Pat. Nos. 5,635,483; 5,780,588). Dolastatins and auristatins have been shown to interfere with microtubule dynamics, GTP hydrolysis, and nuclear and cellular division (Woyke et al (2001) Antimicrob. Agents and Chemother. 45(12):3580-3584) and have anticancer (U.S. Pat. No. 5,663,149) and antifungal activity (Pettit et al (1998) Antimicrob. Agents Chemother, 42:2961-2965). The dolastatin or auristatin drug moiety may be attached to the antibody through the N (amino) terminus or the C (carboxyl) terminus of the peptidic drug moiety (WO 02/088172).
  • Exemplary auristatin embodiments include the N-terminus linked monomethylauristatin drug moieties DE and DF, disclosed in “Senter et al, Proceedings of the American Association for Cancer Research, Volume 45, Abstract Number 623, presented Mar. 28, 2004 and described in United States Patent Publication No. 2005/0238648, the disclosure of which is expressly incorporated by reference in its entirety.
  • An exemplary auristatin embodiment is MMAE (shown in FIG. 10 wherein the wavy line indicates the covalent attachment to a linker (L) of an antibody drug conjugate; see U.S. Pat. No. 6,884,869 expressly incorporated by reference in its entirety).
  • Another exemplary auristatin embodiment is MMAF, shown in FIG. 10 wherein the wavy line indicates the covalent attachment to a linker (L) of an antibody drag conjugate (US 2005/0238649, 5,767,237 and 6,124,431, expressly incorporated by reference in their entirety):
  • Additional exemplary embodiments comprising MMAE or MMAF and various linker components (described further herein) have the following structures and abbreviations (wherein Ab means antibody and p is 1 to about 8):
  • Typically, peptide-based drug moieties can be prepared by forming a peptide bond between two or more amino acids and/or peptide fragments. Such peptide bonds can be prepared, for example, according to the liquid phase synthesis method (see E. Schroder and K. Lubke, “The Peptides”, volume 1, pp 76-136, 1965, Academic Press) that is well known in the field of peptide chemistry. The auristatin/dolastatin drug moieties may be prepared according to the methods of: U.S. Pat. No. 5,635,483; U.S. Pat. No. 5,780,588; Pettit et al (1989) J. Am. Chem. Soc. 111:5463-5465; Pettit et al (1998) Anti-Cancer Drug Design 13:243-277; Pettit, G. R., et al Synthesis, 1996, 719-725; Pettit et al (1996) J. Chem. Soc. Perkin Trans. 1 5:859-863; and Doronina (2003) Nat Biotechnol 21(7):778-784.
  • Calicheamicin
  • In other embodiments, the ADC comprises an antibody of the invention conjugated to one or more calicheamicin molecules. For example, Mylotarg is the first commercial ADC drug and utilizes calicheamicin γ1 as the payload (see U.S. Pat. No. 4,970,198, incorporated by reference in its entirety). Additional calicheamicin derivatives are described in U.S. Pat. Nos. 5,264,586, 5,384,412, 5,550,246, 5,739,116, 5,773,001, 5,767,285 and 5,877,296, all expressly incorporated by reference. The calicheamicin family of antibiotics are capable of producing double-stranded DNA breaks at sub-picomolar concentrations. For the preparation of conjugates of the calicheamicin family, see U.S. Pat. Nos. 5,712,374, 5,714,586, 5,739,116, 5,767,285, 5,770,701, 5,770,710, 5,773,001, 5,877,296 (all to American Cyanamid Company). Structural analogues of calicheamicin which may be used include, but are not limited to, γ1I, α2I, α2I, N-acetyl-γ1I, PSAG and θI1 (Hinman et al., Cancer Research 53:3336-3342 (1993), Lode et al., Cancer Research 58:2925-2928 (1998) and the aforementioned U.S. patents to American Cyanamid). Another anti-tumor drug that the antibody can be conjugated is QFA which is an antifolate. Both calicheamicin and QFA have intracellular sites of action and do not readily cross the plasma membrane. Therefore, cellular uptake of these agents through antibody mediated internalization greatly enhances their cytotoxic effects.
  • Duocarmycins
  • CC-1065 (see U.S. Pat. No. 4,169,888, incorporated by reference) and duocarmycins are members of a family of antitumor antibiotics utilized in ADCs. These antibiotics appear to work through sequence-selectively alkylating DNA at the N3 of adenine in the minor groove, which initiates a cascade of events that result in apoptosis.
  • Important members of the duocarmycins include duocarmycin A (U.S. Pat. No. 4,923,990, incorporated by reference) and duocarmycin SA (U.S. Pat. No. 5,101,038, incorporated by reference), and a large number of analogues as described in U.S. Pat. Nos. 7,517,903, 7,691,962, 5,101,038; 5,641,780; 5,187,186; 5,070,092; 5,070,092; 5,641,780; 5,101,038; 5,084,468, 5,475,092, 5,585,499, 5,846,545, WO2007/089149, WO2009/017394A1, 5,703,080, 6,989,452, 7,087,600, 7,129,261, 7,498,302, and 7,507,420, all of which are expressly incorporated by reference.
    • VI. Other Cytotoxic Agents
  • Other antitumor agents that can be conjugated to the antibodies of the invention include BCNU, streptozoicin, vincristine and 5-fluorouracil, the family of agents known collectively LL-E33288 complex described in U.S. Pat. Nos. 5,053,394, 5,770,710, as well as esperamicins (U.S. Pat. No. 5,877,296).
  • Enzymatically active toxins and fragments thereof which can be used include diphtheria A chain, nonbinding active fragments of diphtheria toxin, exotoxin A chain (from Pseudomonas aeruginosa), ricin A chain, abrin A chain, modeccin A chain, alpha-sarcin, Aleurites fordii proteins, dianthin proteins, Phytolaca americana proteins (PAPI, PAPII, and PAP-S), momordica charantia inhibitor, curcin, cretin, sapaonaria officinalis inhibitor, gelonin, mitogellin, restrictocin, phenomycin, enomycin and the tricothecenes. See, for example, WO 93/21232 published Oct. 28, 1993.
  • The present invention further contemplates an ADC formed between an antibody and a compound with nucleolytic activity (e.g., a ribonuclease or a DNA endonuclease such as a deoxyribonuclease; DNase).
  • For selective destruction of the tumor, the antibody may comprise a highly radioactive atom. A variety of radioactive isotopes are available for the production of radio-conjugated antibodies. Examples include At211, I131, I125, Y90, Re186, Re188, Sm153, Bi212, P32, Pb212 and radioactive isotopes of Lit.
  • The radio- or other labels may be incorporated in the conjugate in known ways. For example, the peptide may be biosynthesized or may be synthesized by chemical amino acid synthesis using suitable amino acid precursors involving, for example, fluorine-19 in place of hydrogen. Labels such as Tc99m or I123, Re186, Re188 and In111 can be attached via a cysteine residue in the peptide, Yttrium-90 can be attached via a lysine residue. The IODOGEN method (Fraker et al (1978) Biochem. Biophys. Res. Commun. 80: 49-57 can be used to incorporate Iodine-123. “Monoclonal Antibodies in Immunoscintigraphy” (Chatal, CRC Press 1989) describes other methods in detail.
  • For compositions comprising a plurality of antibodies, the drug loading is represented by p, the average number of drag molecules per Antibody. Drag loading may range from 1 to 20 drugs (D) per Antibody. The average number of drags per antibody in preparation of conjugation reactions may be characterized by conventional means such as mass spectroscopy, ELISA assay, and HPLC. The quantitative distribution of Antibody-Drug-Conjugates in terms of p may also be determined.
  • In some instances, separation, purification, and characterization of homogeneous Antibody-Drug-conjugates where p is a certain value from Antibody-Drug-Conjugates with other drug loadings may be achieved by means such as reverse phase HPLC or electrophoresis. In exemplary embodiments, p is 2, 3, 4, 5, 6, 7, or 8 or a fraction thereof.
  • The generation of Antibody-drag conjugate compounds can be accomplished by any technique known to the skilled artisan. Briefly, the Antibody-drug conjugate compounds can include an Fc variant antibody as the Antibody unit, a drug, and optionally a linker that joins the drag and the binding agent.
  • A number of different reactions are available for covalent attachment of drags and/or linkers to binding agents. This is can be accomplished by reaction of the amino acid residues of the binding agent, for example, antibody molecule, including the amine groups of lysine, the free carboxylic acid groups of glutamic and aspartic acid, the sulfhydryl groups of cysteine and the various moieties of the aromatic amino acids. A commonly used non-specific methods of covalent attachment is the carbodiimide reaction to link a carboxy (or amino) group of a compound to amino (or carboxy) groups of the antibody. Additionally, bifunctional agents such as dialdehydes or imidoesters have been used to link the amino group of a compound to amino groups of an antibody molecule.
  • Also available for attachment of drugs to binding agents is the Schiff base reaction. This method involves the periodate oxidation of a drug that contains glycol or hydroxy groups, thus forming an aldehyde which is then reacted with the binding agent. Attachment occurs via formation of a. Schiff base with amino groups of the binding agent, Isothiocyanates can also be used as coupling agents for covalently attaching drugs to binding agents. Other techniques are known to the skilled artisan and within the scope of the present invention.
  • In some embodiments, an intermediate, which is the precursor of the linker, is reacted with the drug under appropriate conditions. In other embodiments, reactive groups are used on the drug and/or the intermediate. The product of the reaction between the drug and the intermediate, or the derivatized drag, is subsequently reacted with an Fc variant antibody of the invention under appropriate conditions.
  • It will be understood that chemical modifications may also be made to the desired compound in order to make reactions of that compound more convenient for purposes of preparing conjugates of the invention. For example a functional group e.g. amine, hydroxyl, or sulfhydryl, may be appended to the drug at a position which has minimal or an acceptable effect on the activity or other properties of the drug
    • VII. Linker Units
  • Typically, the antibody-drag conjugate compounds comprise a Linker unit between the drug unit and the antibody unit. In some embodiments, the linker is cleavable under intracellular or extracellular conditions, such that cleavage of the linker releases the drug unit from the antibody in the appropriate environment. For example, solid tumors that secrete certain proteases may serve as the target of the cleavable linker; in other embodiments, it is the intracellular proteases that are utilized. In yet other embodiments, the linker unit is not cleavable and the drug is released, for example, by antibody degradation in lysosomes.
  • In some embodiments, the linker is cleavable by a cleaving agent that is present in the intracellular environment (for example, within a lysosome or endosome or caveolea). The linker can be, for example, a peptidyl linker that is cleaved by an intracellular peptidase or protease enzyme, including, but not limited to, a lysosomal or endosomal protease. In some embodiments, the peptidyl linker is at least two amino acids long or at least three amino acids long or more.
  • Cleaving agents can include, without limitation, cathepsins B and D and plasmin, all of which are known to hydrolyze dipeptide drug derivatives resulting in the release of active drug inside target cells (see, e.g., Dubowchik and Walker, 1999, Pharm. Therapeutics 83:67-123). Peptidyl linkers that are cleavable by enzymes that are present in CD38-expressing cells. For example, a peptidyl linker that is cleavable by the thiol-dependent protease cathepsin-B, which is highly expressed in cancerous tissue, can be used (e.g., a Phe-Leu or a Gly-Phe-Leu-Gly linker (SEQ ID NO: 11). Other examples of such linkers are described, e.g., in U.S. Pat. No. 6,214,345, incorporated herein by reference in its entirety and for all purposes.
  • In some embodiments, the peptidyl linker cleavable by an intracellular protease is a Val-Cit linker or a Phe-Lys linker (see, e.g., U.S. Pat. No. 6,214,345, which describes the synthesis of doxorubicin with the val-cit linker).
  • In other embodiments, the cleavable linker is pH-sensitive, that is, sensitive to hydrolysis at certain pH values. Typically, the pH-sensitive linker hydrolyzable under acidic conditions. For example, an acid-labile linker that is hydrolyzable in the lysosome (for example, a hydrazone, semicarbazone, thiosemicarbazone, cis-aconitic amide, orthoester, acetal, ketal, or the like) may be used. (See, e.g., U.S. Pat. Nos. 5,122,368; 5,824,805; 5,622,929; Dubowchik and Walker, 1999, Pharm. Therapeutics 83:67-123; Neville et al., 1989, Biol. Chem. 264:14653-14661.) Such linkers are relatively stable under neutral pH conditions, such as those in the blood, but are unstable at below pH 5.5 or 5.0, the approximate pH of the lysosome. In certain embodiments, the hydrolyzable linker is a thioether linker (such as, e.g., a thioether attached to the therapeutic agent via an acylhydrazone bond (see, e.g., U.S. Pat. No. 5,622,929).
  • In yet other embodiments, the linker is cleavable under reducing conditions (for example, a disulfide linker). A variety of disulfide linkers are known in the art, including, for example, those that can be formed using SATA (N-succinimidyl-5-acetylthioacetate), SPDP (N-succinimidyl-3-(2-pyridyldithio)propionate), SPDB (N-succinimidyl-3-(2-pyridyldithio)butyrate) and SMPT (N-succinimidyl-oxycarbonyl-alpha-methyl-alpha-(2-pyridyl-dithio)toluene)-, SPDB and SMPT. (See, e.g., Thorpe et al., 1987, Cancer Res. 47:5924-5931; Wawrzynczak et al., In Immunoconjugates: Antibody Conjugates in Radioimagery and Therapy of Cancer (C. W. Vogel ed., Oxford U. Press, 1987. See also U.S. Pat. No. 4,880,935.)
  • In other embodiments, the linker is a malonate linker (Johnson et al., 1995, Anticancer Res. 15:1387-93), a maleimidobenzoyl linker (Lau et al., 1995, Bioorg-Med-Chem. 3(10): 1299-1304), or a 3′-N-amide analog (Lau et al., 1995, Bioorg-Med-Chem. 3(10):1305-12).
  • In yet other embodiments, the linker unit is not cleavable and the drug is released by antibody degradation. (See U.S. Publication No. 2005/0238649 incorporated by reference herein in its entirety and for all purposes).
  • In many embodiments, the linker is self-immolative. As used herein, the term “self-immolative Spacer” refers to a bifunctional chemical moiety that is capable of covalently linking together two spaced chemical moieties into a stable tripartite molecule. It will spontaneously separate from the second chemical moiety if its bond to the first moiety is cleaved. See for example, WO 2007059404A2, WO06110476A2, WO05112919A2, WO2010/062171, WO09/017,394, WO07/089,149, WO 07/018,431, WO04/043493 and WO02/083180, which are directed to drug-cleavable substrate conjugates where the drug and cleavable substrate are optionally linked through a self-immolative linker and which are all expressly incorporated by reference.
  • Often the linker is not substantially sensitive to the extracellular environment. As used herein, “not substantially sensitive to the extracellular environment,” in the context of a linker, means that no more than about 20%, 15%, 10%, 5%, 3%, or no more than about 1% of the linkers, in a sample of antibody-drag conjugate compound, are cleaved when the antibody-drug conjugate compound presents in an extracellular environment (for example, in plasma).
  • Whether a linker is not substantially sensitive to the extracellular environment can be determined, for example, by incubating with plasma the antibody-drug conjugate compound for a predetermined time period (for example, 2, 4, 8, 16, or 24 hours) and then quantitating the amount of free drug present in the plasma.
  • In other, non-mutually exclusive embodiments, the linker promotes cellular internalization. In certain embodiments, the linker promotes cellular internalization when conjugated to the therapeutic agent (that is, in the milieu of the linker-therapeutic agent moiety of the antibody-drug conjugate compound as described herein). In yet other embodiments, the linker promotes cellular internalization when conjugated to both the auristatin compound and the Fc variant antibodies of the invention.
  • A variety of exemplary linkers that can be used with the present compositions and methods are described in WO 2004-010957, U.S. Publication No. 2006/0074008, U.S. Publication No. 20050238649, and U.S. Publication No, 2006/0024317 (each of which is incorporated by reference herein in its entirety and for all purposes).
    • VIII. Drug Loading
  • Drag loading is represented by p and is the average number of Drag moieties per antibody in a molecule. Drug loading (“p”) may be 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20 or more moieties (D) per antibody, although frequently the average number is a fraction or a decimal. Generally, drug loading of from 1 to 4 is frequently useful, and from 1 to 2 is also useful. ADCs of the invention include collections of antibodies conjugated with a range of drag moieties, from 1 to 20. The average number of drug moieties per antibody in preparations of ADC from conjugation reactions may be characterized by conventional means such as mass spectroscopy and, ELISA assay.
  • The quantitative distribution of ADC in terms of p may also be determined. In some instances, separation, purification, and characterization of homogeneous ADC where p is a certain value from ADC with other drug loadings may be achieved by means such as electrophoresis.
  • For some antibody-drug conjugates, p may be limited by the number of attachment sites on the antibody. For example, where the attachment is a cysteine thiol, as in the exemplary embodiments above, an antibody may have only one or several cysteine thiol groups, or may have only one or several sufficiently reactive thiol groups through which a linker may be attached. In certain embodiments, higher drug loading, e.g. p>5, may cause aggregation, insolubility, toxicity, or loss of cellular permeability of certain antibody-drug conjugates. In certain embodiments, the drug loading for an ADC of the invention ranges from 1 to about 8; from about 2 to about 6; from about 3 to about 5; from about 3 to about 4; from about 3.1 to about 3.9; from about 3.2 to about 3.8; from about 3.2 to about 3.7; from about 3.2 to about 3.6; from about 3.3 to about 3.8; or from about 3.3 to about 3.7. Indeed, it has been shown that for certain ADCs, the optimal ratio of drug moieties per antibody may be less than 8, and may be about 2 to about 5. See US 2005-0238649 A1 (herein incorporated by reference in its entirety).
  • In certain embodiments, fewer than the theoretical maximum of drug moieties are conjugated to an antibody during a conjugation reaction. An antibody may contain, for example, lysine residues that do not react with the drug-linker intermediate or linker reagent, as discussed below. Generally, antibodies do not contain many free and reactive cysteine thiol groups which may be linked to a drug moiety; indeed most cysteine thiol residues in antibodies exist as disulfide bridges. In certain embodiments, an antibody may be reduced with a reducing agent such as dithiothreitol (DTT) or tricarbonylethylphosphine (TCEP), under partial or total reducing conditions, to generate reactive cysteine thiol groups. In certain embodiments, an antibody is subjected to denaturing conditions to reveal reactive nucleophilic groups such as lysine or cysteine.
  • The loading (drug/antibody ratio) of an ADC may be controlled in different ways, e.g., by: (i) limiting the molar excess of drug-linker intermediate or linker reagent relative to antibody, (ii) limiting the conjugation reaction time or temperature, (iii) partial or limiting reductive conditions for cysteine thiol modification, (iv) engineering by recombinant techniques the amino acid sequence of the antibody such that the number and position of cysteine residues is modified for control of the number and/or position of linker-drug attachments (such as thioMab or fhioFab prepared as disclosed herein and in WO2006/034488 (herein incorporated by reference in its entirety)).
  • It is to be understood that where more than one nucleophilic group reacts with a drug-linker intermediate or linker reagent followed by drug moiety reagent, then the resulting product is a mixture of ADC compounds with a distribution of one or more drag moieties attached to an antibody. The average number of drugs per antibody may be calculated from the mixture by a dual ELISA antibody assay, which is specific for antibody and specific for the drug. Individual ADC molecules may be identified in the mixture by mass spectroscopy and separated by HPLC, e.g. hydrophobic interaction chromatography.
  • In some embodiments, a homogeneous ADC with a single loading value may be isolated from the conjugation mixture by electrophoresis or chromatography.
    • Methods of Determining Cytotoxic Effect of ADCs
  • Methods of determining whether a Drug or Antibody-Drug conjugate exerts a cytostatic and/or cytotoxic effect on a cell are known. Generally, the cytotoxic or cytostatic activity of an Antibody Drag conjugate can be measured by: exposing mammalian cells expressing a target protein of the Antibody Drag conjugate in a cell culture medium; culturing the cells for a period from about 6 hours to about 5 days; and measuring cell viability. Cell-based in vitro assays can be used to measure viability (proliferation), cytotoxicity, and induction of apoptosis (caspase activation) of the Antibody Drag conjugate.
  • For determining whether an Antibody Drag conjugate exerts a cytostatic effect, a thymidine incorporation assay may be used. For example, cancer cells expressing a target antigen at a density of 5,000 cells/well of a 96-well plated can be cultured for a 72-hour period and exposed to 0.5 μCi of 3H-thymidine during the final 8 hours of the 72-hour period. The incorporation of 3H-thymidine into cells of the culture is measured in the presence and absence of the Antibody Drug conjugate.
  • For determining cytotoxicity, necrosis or apoptosis (programmed cell death) can be measured. Necrosis is typically accompanied by increased permeability of the plasma membrane; swelling of the cell, and rupture of the plasma membrane. Apoptosis is typically characterized by membrane blebbing, condensation of cytoplasm, and the activation of endogenous endonucleases. Determination of any of these effects on cancer cells indicates that an Antibody Drug conjugate is useful in the treatment of cancers.
  • Cell viability can be measured by determining in a cell the uptake of a dye such as neutral red, trypan blue, or ALAMAR™ blue (see, e.g., Page et al., 1993, Intl. J. Oncology 3:473-476). In such an assay, the cells are incubated in media containing the dye, the cells are washed, and the remaining dye, reflecting cellular uptake of the dye, is measured spectrophotometrically. The protein-binding dye sulforhodamine B (SRB) can also be used to measure cytoxicity (Skehan et al., 1990, J. Natl Cancer Inst. 82:1107-12).
  • Alternatively, a tetrazolium salt, such as MTT, is used in a quantitative colorimetric assay for mammalian cell survival and proliferation by detecting living, but not dead, cells (see, e.g., Mosmann, 1983, J. Immunol. Methods 65:55-63).
  • Apoptosis can be quantitated by measuring, for example, DNA fragmentation. Commercial photometric methods for the quantitative in vitro determination of DNA fragmentation are available. Examples of such assays, including TUNEL (which detects incorporation of labeled nucleotides in fragmented DNA) and ELISA-based assays, are described in Biochemica, 1999, no. 2, pp. 34-37 (Roche Molecular Biochemicals).
  • Apoptosis can also be determined by measuring morphological changes in a cell. For example, as with necrosis, loss of plasma membrane integrity can be determined by measuring uptake of certain dyes (e.g., a fluorescent dye such as, for example, acridine orange or ethidium bromide). A method for measuring apoptotic cell number has been described by Duke and Cohen, Current Protocols in Immunology (Coligan et al. eds., 1992, pp. 3.17.1-3.17.16). Cells also can be labeled with a DNA dye (e.g., acridine orange, ethidium bromide, or propidium iodide) and the cells observed for chromatin condensation and margination along the inner nuclear membrane. Other morphological changes that can be measured to determine apoptosis include, e.g., cytoplasmic condensation, increased membrane blebbing, and cellular shrinkage.
  • The presence of apoptotic cells can be measured in both the attached and “floating” compartments of the cultures. For example, both compartments can be collected by removing the supernatant, trypsinizing the attached cells, combining the preparations following a centrifugation wash step (e.g., 10 minutes at 2000 rpm), and detecting apoptosis (e.g., by measuring DNA fragmentation). (See, e.g., Piazza et al., 1995, Cancer Research 55:3110-16).
  • In vivo, the effect of a therapeutic composition of the Fc variant antibody of the invention can be evaluated in a suitable animal model. For example, xenogenic cancer models can be used, wherein cancer explants or passaged xenograft tissues are introduced into immune compromised animals, such as nude or SCID mice (Klein et al., 1997, Nature Medicine 3: 402-408). Efficacy can be measured using assays that measure inhibition of tumor formation, tumor regression or metastasis, and the like.
  • The therapeutic compositions used in the practice of the foregoing methods can be formulated into pharmaceutical compositions comprising a carrier suitable for the desired delivery method. Suitable carriers include any material that when combined with the therapeutic composition retains the anti-tumor function of the therapeutic composition and is generally non-reactive with the patient's immune system. Examples include, but are not limited to, any of a number of standard pharmaceutical carriers such as sterile phosphate buffered saline solutions, bacteriostatic water, and the like (see, generally, Remington's Pharmaceutical Sciences 16th Edition, A. Osal., Ed., 1980).
  • Glycosylation
  • Another type of covalent modification is alterations in glycosylation. In another embodiment, the antibodies disclosed herein can be modified to include one or more engineered glycoforms. By “engineered glycoform” as used herein is meant a carbohydrate composition that is covalently attached to the antibody, wherein said carbohydrate composition differs chemically from that of a parent antibody. Engineered glycoforms may be useful for a variety of purposes, including but not limited to enhancing or reducing effector function. A preferred form of engineered glycoform is afucosylation, which has been shown to be correlated to an increase in ADCC function, presumably through tighter binding to the FcγRIIIa receptor. In this context, “afucosylation” means that the majority of the antibody produced in the host cells is substantially devoid of fucose, e.g. 90-95-98% of the generated antibodies do not have appreciable fucose as a component of the carbohydrate moiety of the antibody (generally attached at N297 in the Fc region). Defined functionally, afucosylated antibodies generally exhibit at least a 50% or higher affinity to the FcγRIIIa receptor.
  • Engineered glycoforms may be generated by a variety of methods known in the art (Umaña et al., 1999, Nat Biotechnol 17:176-180; Davies et al., 2001, Biotechnol Bioeng 74:288-294; Shields et al., 2002, J Biol Chem 277:26733-26740; Shinkawa et al., 2003, J Biol Chem 278:3466-3473; U.S. Pat. No. 6,602,684; U.S. Ser. No. 10/277,370; U.S. Ser. No. 10/113,929; PCT WO 00/61739A1; PCT WO 01/29246A1; PCT WO 02/31140A1; PCT WO 02/30954A1, all entirely incorporated by reference; (Potelligent® technology [Biowa, Inc., Princeton, N.J.]; GlycoMAb® glycosylation engineering technology [Glycart Biotechnology AG, Zürich, Switzerland]). Many of these techniques are based on controlling the level of fucosylated and/or bisecting oligosaccharides that are covalently attached to the Fc region, for example by expressing an IgG in various organisms or cell lines, engineered or otherwise (for example Lee-13 CHO cells or rat hybridoma YB2/0 cells, by regulating enzymes involved in the glycosylation pathway (for example FUT8 [α1,6-fucosyltranserase] and/or β1-4-N-acetylglucosaminyltransferase III [GnTIII]), or by modifying carbohydrate(s) after the IgG has been expressed. For example, the “sugar engineered antibody” or “SEA technology” of Seattle Genetics functions by adding modified saccharides that inhibit fucosylation during production; see for example 20090317869, hereby incorporated by reference in its entirety. Engineered glycoform typically refers to the different carbohydrate or oligosaccharide; thus an antibody can include an engineered glycoform.
  • Alternatively, engineered glycoform may refer to the IgG variant that comprises the different carbohydrate or oligosaccharide. As is known in the art, glycosylation patterns can depend on both the sequence of the protein (e.g., the presence or absence of particular glycosylation amino acid residues, discussed below), or the host cell or organism in which the protein is produced. Particular expression systems are discussed below.
  • Glycosylation of polypeptides is typically either N-linked or O-linked. N-linked refers to the attachment of the carbohydrate moiety to the side chain of an asparagine residue. The tri-peptide sequences asparagine-X-serine and asparagine-X-threonine, where X is any amino acid except proline, are the recognition sequences for enzymatic attachment of the carbohydrate moiety to the asparagine side chain. Thus, the presence of either of these tri-peptide sequences in a polypeptide creates a potential glycosylation site. O-linked glycosylation refers to the attachment of one of the sugars N-acetylgalactosamine, galactose, or xylose, to a hydroxyamino acid, most commonly serine or threonine, although 5-hydroxyproline or 5-hydroxylysine may also be used.
  • Addition of glycosylation sites to the antibody is conveniently accomplished by altering the amino acid sequence such that it contains one or more of the above-described tri-peptide sequences (for N-linked glycosylation sites). The alteration may also be made by the addition of, or substitution by, one or more serine or threonine residues to the starting sequence (for O-linked glycosylation sites). For ease, the antibody amino acid sequence is preferably altered through changes at the DNA level, particularly by mutating the DNA encoding the target polypeptide at preselected bases such that codons are generated that will translate into the desired amino acids.
  • Another means of increasing the number of carbohydrate moieties on the antibody is by chemical or enzymatic coupling of glycosides to the protein. These procedures are advantageous in that they do not require production of the protein in a host cell that has glycosylation capabilities for N- and O-linked glycosylation. Depending on the coupling mode used, the sugar(s) may be attached to (a) arginine and histidine, (b) free carboxyl groups, (c) free sulfhydryl groups such as those of cysteine, (d) free hydroxyl groups such as those of serine, threonine, or hydroxy-proline, (e) aromatic residues such as those of phenylalanine, tyrosine, or tryptophan, or (f) the amide group of glutamine. These methods are described in WO 87/05330 and in Aplin and Wriston, 1981, CRC Crit. Rev. Biochem., pp. 259-306, both entirely incorporated by reference.
  • Removal of carbohydrate moieties present on the starting antibody (e.g. post-translationally) may be accomplished chemically or enzymatically. Chemical deglycosylation requires exposure of the protein to the compound tritfluoromethanesulfonic acid, or an equivalent compound. This treatment results in the cleavage of most or all sugars except the linking sugar (N-acetylglucosamine or N-acetylgalactosamine), while leaving the polypeptide intact. Chemical deglycosylation is described by Hakimuddin et al., 1987, Arch. Biochem. Biophys. 259:52 and by Edge et al., 1981, Anal, Biochem. 118:131, both entirely incorporated by reference. Enzymatic cleavage of carbohydrate moieties on polypeptides can be achieved by the use of a variety of endo- and exo-glycosidases as described by Thotakura et al., 1987, Meth. Enzymol. 138:350, entirely incorporated by reference. Glycosylation at potential glycosylation sites may be prevented by the use of the compound tunicamycin as described by Duskin et al., 1982, J, Biol, Chem, 257:3105, entirely incorporated by reference, Tunicamycin blocks the formation of protein-N-glycoside linkages.
  • Another type of covalent modification of the antibody comprises linking the antibody to various nonproteinaceous polymers, including, but not limited to, various polyols such as polyethylene glycol, polypropylene glycol or polyoxyalkylenes, in the manner set forth in, for example, 2005-2006 PEG Catalog from Nektar Therapeutics (available at the Nektar website) U.S. Pat. No. 4,640,835; 4,496,689; 4,301,144; 4,670,417; 4,791,192 or 4,179,337, all entirely incorporated by reference. In addition, as is known in the art, amino acid substitutions may be made in various positions within the antibody to facilitate the addition of polymers such as PEG. See for example, U.S. Publication No. 2005/0114037A1, entirely incorporated by reference.
    • IX. Nucleic Acids and Host Cells
  • Included within the invention are the nucleic acids encoding the Fc variant antibodies of the invention. In the case where both a heavy and light chain constant domains are included in the Fc variant antibody, generally these are made using nucleic acids encoding each, that are combined into standard host cells (e.g. CHO cells, etc.) to produce the tetrameric structure of the antibody. If only one Fc variant engineered constant domain is being made, only a single nucleic acid will be used.
    • X. Antibody Compositions for In Vivo Administration
  • The use of the Fc variant antibodies of the invention in therapy will depend on the antigen binding component; e.g. in the case of full length standard therapeutic antibodies, on the antigen to which the antibody's Fv binds. That is, as will be appreciated by those in the art, the treatment of specific diseases can be done with the additional benefit of increased half life of the molecule. This can result in a variety of benefits, including, but not limited to, less frequent dosing (which can lead to better patient compliance), lower dosing, and lower production costs.
  • Formulations of the antibodies used in accordance with the present invention are prepared for storage by mixing an antibody having the desired degree of purity with optional pharmaceutically acceptable carriers, excipients or stabilizers (Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. [1980]), in the form of lyophilized formulations or aqueous solutions. Acceptable carriers, excipients, or stabilizers are nontoxic to recipients at the dosages and concentrations employed, and include buffers such as phosphate, citrate, and other organic acids; antioxidants including ascorbic acid and methionine; preservatives (such as octadecyldimethylbenzyl ammonium chloride; hexamethonium chloride; benzalkonium chloride, benzethonium chloride; phenol, butyl or benzyl alcohol; alkyl parabens such as methyl or propyl paraben; catechol; resorcinol; cyclohexanol; 3-pentanol; and m-cresol); low molecular weight (less than about 10 residues) polypeptides; proteins, such as serum albumin, gelatin, or immunoglobulins; hydrophilic polymers such as polyvinylpyrrolidone; amino acids such as glycine, glutamine, asparagine, histidine, arginine, or lysine; monosaccharides, disaccharides, and other carbohydrates including glucose, mannose, or dextrins; chelating agents such as EDTA; sugars such as sucrose, mannitol, trehalose or sorbitol; salt-forming counter-ions such as sodium; metal complexes (e.g. Zn-protein complexes); and/or non-ionic surfactants such as TWEEN™, PLURONICS™ or polyethylene glycol (PEG).
  • The formulation herein may also contain more than one active compound as necessary for the particular indication being treated, preferably those with complementary activities that do not adversely affect each other. For example, it may be desirable to provide antibodies with other specificities. Alternatively, or in addition, the composition may comprise a cytotoxic agent, cytokine, growth inhibitory agent and/or small molecule antagonist. Such molecules are suitably present in combination in amounts that are effective for the purpose intended.
  • The active ingredients may also be entrapped in microcapsules prepared, for example, by coacervation techniques or by interfacial polymerization, for example, hydroxymethylcellulose or gelatin-microcapsules and poly-(methylmethacylate) microcapsules, respectively, in colloidal drug delivery systems (for example, liposomes, albumin microspheres, microemulsions, nano-particles and nanocapsules) or in macroemulsions. Such techniques are disclosed in Remington's Pharmaceutical Sciences 16th edition, Osol, A. Ed. (1980).
  • The formulations to be used for in vivo administration should be sterile, or nearly so. This is readily accomplished by filtration through sterile filtration membranes.
  • Sustained-release preparations may be prepared. Suitable examples of sustained-release preparations include semipermeable matrices of solid hydrophobic polymers containing the antibody, which matrices are in the form of shaped articles, e.g. films, or microcapsules. Examples of sustained-release matrices include polyesters, hydrogels (for example, poly(2-hydroxyethyl-methacrylate), or poly(vinylalcohol)), polylactides (U.S. Pat. No. 3,773,919), copolymers of L-glutamic acid and .gamma. ethyl-L-glutamate, non-degradable ethylene-vinyl acetate, degradable lactic acid-glycolic acid copolymers such as the LUPRON DEPOT™ (injectable microspheres composed of lactic acid-glycolic acid copolymer and leuprolide acetate), and poly-D-(−)-3-hydroxybutyric acid. While polymers such as ethylene-vinyl acetate and lactic acid-glycolic acid enable release of molecules for over 100 days, certain hydrogels release proteins for shorter time periods.
  • When encapsulated antibodies remain in the body for a long time, they may denature or aggregate as a result of exposure to moisture at 37° C., resulting in a loss of biological activity and possible changes in immunogenicity. Rational strategies can be devised for stabilization depending on the mechanism involved. For example, if the aggregation mechanism is discovered to be intermolecular S—S bond formation through thio-disulfide interchange, stabilization may be achieved by modifying sulfhydryl residues, lyophilizing from acidic solutions, controlling moisture content, using appropriate additives, and developing specific polymer matrix compositions.
    • XI. Administrative Modalities
  • The antibodies and chemotherapeutic agents of the invention are administered to a subject, in accord with known methods, such as intravenous administration as a bolus or by continuous infusion over a period of time, by intramuscular, intraperitoneal, intracerobrospinal, subcutaneous, intra-articular, intrasynovial, intrathecal, oral, topical, or inhalation routes. Intravenous or subcutaneous administration of the antibody is preferred,
    • XII. Treatment Modalities
  • 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 patient survival rate; and (7) some relief from one or more symptoms associated with the disease or condition.
  • 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 including bone marrow aspiration (BMA) and counting of tumor cells in the circulation.
  • 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.
  • Thus for B cell tumors, the subject may experience a decrease in the so-called B symptoms, i.e., night sweats, fever, weight loss, and/or urticaria. For pre-malignant conditions, therapy with an Fc variant therapeutic agent may block and/or prolong the time before development of a related malignant condition, for example, development of multiple myeloma in subjects suffering from monoclonal gammopathy of undetermined significance (MGUS).
  • An improvement in the disease may be characterized as a complete response. By “complete response” is intended an absence of clinically detectable disease with normalization of any previously abnormal radiographic studies, bone marrow, and cerebrospinal fluid (CSF) or abnormal monoclonal protein in the case of myeloma.
  • Such a response may persist for at least 4 to 8 weeks, or sometimes 6 to 8 weeks, following treatment according to the methods of the invention. Alternatively, an improvement in the disease may be categorized as being a partial response. By “partial response” is intended at least about a 50% decrease in all measurable tumor burden (i.e., the number of malignant cells present in the subject, or the measured bulk of tumor masses or the quantity of abnormal monoclonal protein) in the absence of new lesions, which may persist for 4 to 8 weeks, or 6 to 8 weeks.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • 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.
  • The efficient dosages and the dosage regimens for the Fc variant antibodies used in the present invention depend on the disease or condition to be treated and may be determined by the persons skilled in the art.
  • An exemplary, non-limiting range for a therapeutically effective amount of an Fc variant antibody used in the present invention is about 0, 1-100 mg/kg, such as about 0.1-50 mg/kg, for example about 0.1-20 mg/kg, such as about 0.1-10 mg/kg, for instance about 0.5, about such as 0.3, about 1, or about 3 mg/kg. In another embodiment, he antibody is administered in a dose of 1 mg/kg or more, such as a dose of from 1 to 20 mg/kg, e.g. a dose of from 5 to 20 mg/kg, e.g. a dose of 8 mg/kg.
  • A medical professional having ordinary skill in the art may readily determine and prescribe the effective amount of the pharmaceutical composition required. For example, a physician or a veterinarian could start doses of the medicament employed in the pharmaceutical 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.
  • In one embodiment, the Fc variant antibody is administered by infusion in a weekly dosage of from 10 to 500 mg/kg such as of from 200 to 400 mg/kg Such administration may be repeated, e.g., 1 to 8 times, such as 3 to 5 times. The administration may be performed by continuous infusion over a period of from 2 to 24 hours, such as of from 2 to 12 hours.
  • In one embodiment, the Fc variant antibody is administered by slow continuous infusion over a long period, such as more than 24 hours, if required to reduce side effects including toxicity.
  • In one embodiment the Fc variant antibody is administered in a weekly dosage of from 250 mg to 2000 mg, such as for example 300 mg, 500 mg, 700 mg, 1000 mg, 1500 mg or 2000 mg, for up to 8 times, such as from 4 to 6 times. The administration may be performed by continuous infusion over a period of from 2 to 24 hours, such as of from 2 to 12 hours. Such regimen may be repeated one or more times as necessary, for example, after 6 months or 12 months. The dosage may be determined or adjusted by measuring the amount of compound of the present invention in the blood upon administration by for instance taking out a biological sample and using anti-idiotypic antibodies which target the antigen binding region of the Fc variant antibody.
  • In a further embodiment, the Fc variant antibody is administered once weekly for 2 to 12 weeks, such as for 3 to 10 weeks, such as for 4 to 8 weeks.
  • In one embodiment, the Fc variant antibody is administered by maintenance therapy, such as, e.g., once a week for a period of 6 months or more.
  • In one embodiment, the Fc variant antibody is administered by a regimen including one infusion of an Fc variant antibody followed by an infusion of an Fc variant antibody conjugated to a radioisotope. The regimen may be repeated, e.g., 7 to 9 days later.
  • As non-limiting examples, treatment according to the present invention may be provided as a daily dosage of an antibody in an amount of about 0.1-100 mg/kg, such as 0.5, 0.9, 1.0, 1.1, 1.5, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 40, 45, 50, 60, 70, 80, 90 or 100 mg/kg, per day, on at least one of day 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, or 40, or alternatively, at least one of week 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 after initiation of treatment, or any combination thereof, using single or divided doses of every 24, 12, 8, 6, 4, or 2 hours, or any combination thereof.
  • In some embodiments the Fc variant antibody molecule thereof is used in combination with one or more additional therapeutic agents, e.g. a chemotherapeutic agent. Non-limiting examples of DNA damaging chemotherapeutic agents include topoisomerase I inhibitors (e.g., irinotecan, topotecan, camptothecin and analogs or metabolites thereof, and doxorubicin); topoisomerase II inhibitors (e.g., etoposide, teniposide, and daunorubicin); alkylating agents (e.g., melphalan, chlorambucil, busulfan, thiotepa, ifosfamide, carmustine, lomustine, semustine, streptozocin, decarbazine, methotrexate, mitomycin C, and cyclophosphamide); DNA intercalators (e.g., cisplatin, oxaliplatin, and carboplatin); DNA intercalators and free radical generators such as bleomycin; and nucleoside mimetics (e.g., 5-fluorouracil, capecitibine, gemcitabine, fludarabine, cytarabine, mercaptopurine, thioguanine, pentostatin, and hydroxyurea).
  • Chemotherapeutic agents that disrupt cell replication include: paclitaxel, docetaxel, and related analogs; vincristine, vinblastin, and related analogs; thalidomide, lenalidomide, and related analogs (e.g., CC-5013 and CC-4047); protein tyrosine kinase inhibitors (e.g., imatinib mesylate and gefitinib); proteasome inhibitors (e.g., bortezomib); NF-κB inhibitors, including inhibitors of IκB kinase; antibodies which bind to proteins overexpressed in cancers and thereby downregulate cell replication (e.g., trastuzumab, rituximab, cetuximab, and bevacizumab); and other inhibitors of proteins or enzymes known to be upregulated, over-expressed or activated in cancers, the inhibition of which downregulates cell replication.
  • In some embodiments, the antibodies of the invention can be used prior to, concurrent with, or after treatment with Velcade® (bortezomib).
    • EXAMPLES
  • 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.
    • Example 1 DNA Construction, Expression, and Purification of Fc Variants
  • Amino acid modifications were engineered in the Fc region of IgG antibodies to improve their affinity for the neonatoal Fc receptor FcRn. Variants were screened in the context of a number of different human IgG constant chains (FIG. 2), including IgG1, IgG2, and a hybrid IgG sequences that contains the CH1 and upper hinge of IgG1 and the Fc region of IgG2. It will be appreciated by those skilled in the art that because of the different interactions of the IgG1 and IgG2 Fc region with FcγRs and complement, these different parent Fc regions will have different FcγR− and complement-mediated effector function properties. Exemplary sequences of Fc variants in the context of these parent IgG constant chains are shown in FIG. 3.
  • Fc variants were engineered in the context of an antibody targeting vascular endothelial factor (VEGF). The heavy and light chain variable regions (VH and VL) are those of a humanized version of the antibody A4.6.1, also referred to as bevacizumab (Avastin®), which is approved for the treatment of a variety of cancers. The amino acid sequences of the VH and VL regions of this antibody are shown in FIG. 4.
  • Genes encoding the heavy and light chains of the anti-VEGF antibodies were constructed in the mammalian expression vector pTT5. Human IgG1 and IgG2 constant chain genes were obtained from IMAGE clones and subcloned into the pTT5 vector. The IgG1/2 gene was constructed using PCR mutagenesis. VH and VL genes encoding the anti-VEGF antibodies were synthesized commercially (Blue Heron Biotechnologies, Bothell Wash.), and subcloned into the vectors encoding the appropriate CL, IgG1, IgG2, and IgG1/2 constant chains, Amino acid modifications were constructed using site-directed mutagenesis using the QuikChange® site-directed mutagenesis methods (Stratagene, La Jolla Calif.). All DNA was sequenced to confirm the fidelity of the sequences.
  • Plasmids containing heavy chain gene (VH—Cγ1-Cγ2-Cγ3) were co-transfected with plasmid containing light chain gene (VL-Cκ) into 293E cells using lipofectamine (Invitrogen, Carlsbad Calif.) and grown in FreeStyle 293 media (Invitrogen, Carlsbad Calif.). After 5 days of growth, the antibodies were purified from the culture supernatant by protein A affinity using the MabSelect resin (GE Healthcare), Antibody concentrations were determined by bicinchoninic acid (BCA) assay (Pierce).
    • Example 2 Fc Variant Antibodies Maintain Binding to Antigen
  • The fidelity of the expressed variant antibodies was confirmed by demonstrating that they maintained specificity for antigen, VEGF binding was monitored using surface plasmon resonance (SPR, Biacore), performed using a Biacore 3000 instrument. Recombinant VEGF (VEGF-165, PeproTech, Rocky Hill, N.J.) was adhered to a CM5 chip surface by coupling with N-hydroxysuccinimide/N-ethyl-N′-(-3-dimethylamino-propyl) carbodiimide (NHS/EDC) using standard methods. WT and variant antibodies were injected as analytes, and response, measured in resonance units (RU), was acquired. The dissociation phase was too slow to measure true equilibrium constants, and so relative binding was determined by measuring RU's at the end of the association phase, which should be proportional to the protein concentration (which is held constant in the experiment) and the association rate constant. The data (FIG. 5) show that the variant anti-VEGF antibodies maintain binding to antigen, in contrast to the negative control anti-Her2 antibody which does not bind VEGF.
    • Example 3 Measurement of Binding to Human FcRn
  • Binding of variant antibodies to human FcRn was measured at pH 6.0, the pH at which it is naturally bound in endosomes. Vectors encoding beta 2 microglobulin and His-tagged alpha chain genes of FcRn were constructed, co-transfected into 293T cells, and purified using nickel chromatography. Antibody affinity for human FcRn (hFcRn) at pH 6.0 was measured on a Biacore 3000 instrument by coupling human FcRn to a CM5 chip surface using standard NHS/EDC chemistry. WT and variant antibodies were used in the mobile phase at 25-100 nM concentration and response was measured in resonance units. Association and dissocation phases at pH 6.0 were acquired, followed by an injection of pH 7.4 buffer to measure release of antibody from receptor at the higher pH. A cycle with antibody and buffer only provided baseline response, which was subtracted from each sample sensorgram.
  • FIG. 6 shows Biacore sensorgrams for binding of native IgG1 and select Fc variant antibodies to human FcRn at the two relevant pH's. The data show that wild-type and variant antibodies bind readily to FcRn chip at pH 6.0 and dissociate slowly at that pH, as they would in the endosome, yet release rapidly at pH7.4, as they would upon recycling of endosome to the membrane and exposure to the higher pH of serum.
  • The FcRn association/dissociation curves did not fit to a simple Langmuir model, possibly due to the antibody and receptor multi-valency or chip heterogeneity. Pseudo-Ka values (referred to as Ka*) were determined by fitting to a conformational change model with the change in refractive index (RI) fixed at 0 RU. These values for select variant antibodies are plotted in FIG. 7. The relative affinity of each variant as compared to its parent IgG was calculated according to the equation Fold=(WT Ka*/Variant Ka*).
    • Example 4 Pharmacokinetic Experiments in Human FcRn Knock-in Mice
  • To test the ability of select variants to improve half-life in vivo, pharmacokinetic experiments were performed in B6 mice that are homozygous knock-outs for murine FcRn and heterozygous knock-ins of human FcRn (mFcRn−/−, hFcRn+) (Petkova et al., 2006, Int. Immunol 18(12): 1759-69, entirely incorporated by reference), herein referred to as hFcRn or hFcRn+ mice. A single, intravenous tail vein injection of anti-VEGF antibody (2 mg/kg) was given to groups of 4-7 female mice randomized by body weight (20-30 g range). Blood (˜50 ul) was drawn from the orbital plexus at each time point, processed to serum, and stored at −80° C. until analysis. Study durations were 28 or 49 days.
  • Antibody concentrations were determined using two ELISA assays. In the first two studies (referred to as Study 1 and Study 2), goat anti-human Fc antibody (Jackson Immune research) was adhered to the plate, wells were washed with PBST (phosphate buffered saline with 0.05% Tween) and blocked with 3% BSA in PBST. Serum or calibration standards were the added, followed by PBST washing, addition of europium labeled anti-human IgG (Perkin Elmer), and further PBST washing. The time resolved fluorescence signal was collected. For Studies 3-5, serum concentration was detected using a similar ELISA, but recombinant VEGF (VEGF-165, PeproTech, Rocky Hill, N.J.) was used as capture reagent and detection was carried out with biotinylated anti-human kappa antibody and europium-labeled streptavidin. PK parameters were determined for individual mice with a non-compartmental model using WinNonLin (Pharsight Inc, Mountain View Calif.). Nominal times and dose were used with uniform weighing of points. The time points used (lambda Z ranges) were from 4 days to the end of the study, although all time points were used for the faster clearing mutants, P257N and P257L.
  • Five antibody PK studies in mFcRn−/− hFcRn+ mice were carried out. FIG. 8 a-8 b shows serum concentration data for WT and variant IgG1 (Study 3) and IgG2 (Study 5) antibodies respectively. Fitted PK parameters from all in vivo PK studies carried out in mFcRn−/− hFcRn+ mice are provided in FIG. 9, PK data include half-life, which represents the beta phase that characterizes elimination of antibody from serum, Cmax, which represents the maximal observed serum concentration, AUG, which represents the area under the concetration time curve, and clearance, which represents the clearance of antibody from serum. Also provided for each variant is the calculated fold improvement or reduction in half-life relative to the IgG1 or IgG2 parent antibody [Fold half-life=half-life(variant)/half-life (WT)].
    • Example 5 Pharmacokinetic Experiment in Nonhuman Primates
  • The PK properties of biologics in non-human primates are well-established to be predictive of their properties in humans. A PK study was carried out in cynomolgus monkeys (macaca fascicularis) in order to evaluate the capacity of the variant anti-VEGF antibodies to improve serum half-life in non-human primates.
  • In preparation for a PK study in cynomolgus monkeys, binding of the variant antibodies to cynomolgus (cyno) FcRn (cFcRn) at pH 6.0 was measured. cFcRn was constructed, expressed, and purified as described above for human FcRn. Binding of variant anti-VEGF antibodies to cFcRn was measured using Biacore as described above. The data is provided in FIG. 10 a-10 b. The results show that the variants improve affinity for cyno FcRn similarly as they do for human FcRn. Dissociation at the higher pH (7.4) was also very rapid (data not shown), similar to as was observed for binding to human FcRn. These results are not surprising given the high sequence homology of the human and cyno receptors (FcRn alpha chain 96%, beta-2-microglobulin 91%).
  • The PK of the variants were studied in vivo in non-human primates. Male cynomolgus monkeys (macaca fascicularis, also called crab-eating Macaque) weighing 2.3-5.1 kg were randomized by weight and divided into 5 groups with 3 monkeys per group. The monkeys were given a single, 1 hour peripheral vein infusion of 4 mg/kg antibody. Blood samples (1 ml) were drawn from a separate vein from 5 minutes to 90 days after completion of the infusion, processed to serum and stored at −70 C. Animals were not harmed during these studies.
  • Antibody concentrations were determined using the VEGF capture method as described above. PK parameters were determined by fitting the concentrations versus time to a non-compartmental model as was done in the mouse PK studies. However, time points from day 10 to day 90 were used for PK parameter determinations. The PK results are plotted in FIG. 11, and the fitted parameters are provided in FIG. 12. The results show that the variants enhanced the in vivo half-life of antibody up to 3.2-fold. In the best case (the 428L/434S variant) half-life was extended from 9.7 days to 31.1 days. The PK results obtained in cynomolgus monkeys are consistent with those obtained in mFcRn−/− hFcRn+ mice, validating the hFcRn mouse model as a system for assessing the in vivo PK properties of the variants, and supporting the conclusions from those studies.
    • Example 6 Engineering Additional Fc Variants that Extend In Vivo Half-Life
  • New variants were engineered to further screen for modifications that extend in vivo halt-life. Designed substitutions are shown in FIG. 13, Variants were constructed in the context of an antibody with the bevacizumab variant region and IgG1/2 N434S constant region; however, variants may be constructed in any IgG isotype. Variants were constructed, expressed, and purified as described above.
  • Variants were screened for binding to human FcRn at pH 6.0 by Biacore. Anti-VEGF antibodies were captured to a VEGF coupled chip, a single concentration of FcRn analyte was flowed over the chip (association phase), and then buffer was washed over to dissociate FcRn analyte (dissociation phase). The dissociation off-rate (koff) was determined by fitting the dissociation phase data to a 1:1 Langmuir dissociation model. The results are shown numerically in FIG. 14, and plotted in FIG. 15. As can be seen, a number of the designed variants improve FcRn binding (reduce the koff) relative to the IgG1/2 N434S background.
  • The FcRn binding of select variants was tested using the same Biacore format but with an analyte (FcRn) concentration series in order to obtain accurate equilibrium dissociation constants (KDs). Sensorgrams at multiple analyte concentrations were fit globally to a 1:1 Langmuir binding model. Resulting kinetic and equilibrium binding constants are presented in FIG. 16, along with the Fold KD and Fold koff relative to IgG1 WT and IgG1/2 N434S respectively. Data are plotted in FIGS. 17 and 18. A number of variants, comprising several different substitutions improve binding to human FcRn. Beneficial substitutions include but are not limited to T307Q, Q311I, Q311V, A378V, S426V, S426T, Y436I, and Y436V. The successful engineering at positions 378 and 426 is surprising giving that they are more distal to the FcRn binding interface on Fc.
  • Additional substitutions were designed to explore whether other substitutions at these positions may provide improved binding to FcRn. These variants are listed in FIG. 19. Based on the collective data, a new library of variant combinations was designed to further screen for Fc variants that have the potential to extend antibody half-life in vivo. These variants are listed in FIG. 20.
  • Variants were constructed, expressed, and purified as described above. Variants were screened for binding to human FcRn at pH 6.0 by Biacore. Anti-VEGF antibodies were captured to a VEGF coupled chip, a single concentration of FcRn analyte was flowed over the chip (association phase), and then buffer was washed over to dissociate FcRn analyte (dissociation phase). The dissociation off-rate (koff) was determined by fitting the dissociation phase data to a 1:1 Langmuir dissociation model. The results are shown numerically in FIG. 21, and plotted in FIG. 22. As can be seen, a number of the designed variants improve FcRn binding (reduce the koff).
  • In vivo pharmacokinetic properties of the variants were tested in hFcRn+ mice as described above. A single, intravenous tail vein injection of anti-VEGF antibody (2 mg/kg) was given. Antibody concentrations were determined using the VEGF-capture ELISA assay described above. FIG. 23 shows mean serum concentration data for Fc variant and IgG1/2 parent anti-VEGF antibodies. Fitted half-lives of individual mice and means are provided in FIG. 24. FIG. 25 shows a scatter plot of the fitted half-lives from the individual mice in the study. The results indicate that the engineered Fc variants extend half-life relative to the parent IgG1/2 antibody, as well as the IgG1/2 N434S variant.
  • 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. All references cited herein are incorporated in their entirety.

Claims (5)

1. An antibody comprising a variant Fc region as compared to a parent Fc region, wherein said variant Fc region comprises a first mutation which is a serine at position 434 and a second mutation selected from a group consisting of: an isoleucine at position 311, a valine at position 311, an isoleucine at position 436, and a valine at position 436, wherein said antibody has increased serum half-life as compared to an antibody comprising said parent Fc region, and wherein numbering is according to the ELI index.
2. An antibody comprising a variant Fc region as compared to a parent Fc region, wherein said variant Fc region comprises a first mutation which is a serine at position 434 and a second mutation selected from a group consisting of: an isoleucine at position 311, a valine at position 311, an isoleucine at position 436, and a valine at position 436, wherein said antibody has increased binding affinity to a human FcRn receptor as compared to an antibody comprising said parent Fc region, and wherein numbering is according to the EU index.
3. A nucleic acid encoding the variant Fc region of claim 1 or 2.
4. A host cell comprising the nucleic acid of claim 21.
5. A method comprising administering an antibody to a subject, said method comprising administering an antibody comprising a variant Fc region as compared to a parent Fc region, wherein said variant Fc region comprises a first mutation which is a serine at position 434 and a second mutation selected from a group consisting of: an isoleucine at position 311, a valine at position 311, an isoleucine at position 436, and a valine at position 436, wherein said antibody has increased serum half-life as compared to an antibody comprising said parent Fc region, and wherein numbering is according to the EU index.
US13/973,934 2004-11-12 2013-08-22 Fc variants that extend antibody half-life Abandoned US20140056879A1 (en)

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US62776304P 2004-11-12 2004-11-12
US64288605P 2005-01-11 2005-01-11
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US66931105P 2005-04-06 2005-04-06
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US69020005P 2005-06-13 2005-06-13
US69660905P 2005-07-05 2005-07-05
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US72645305P 2005-10-12 2005-10-12
US11/274,065 US9200079B2 (en) 2004-11-12 2005-11-14 Fc variants with altered binding to FcRn
US11/436,266 US20070135620A1 (en) 2004-11-12 2006-05-17 Fc variants with altered binding to FcRn
US95153607P 2007-07-24 2007-07-24
US11/932,151 US8802820B2 (en) 2004-11-12 2007-10-31 Fc variants with altered binding to FcRn
US1679307P 2007-12-26 2007-12-26
US3135308P 2008-02-25 2008-02-25
US4635308P 2008-04-18 2008-04-18
US5017208P 2008-05-02 2008-05-02
US7977908P 2008-07-10 2008-07-10
US9917808P 2008-09-22 2008-09-22
US12/341,769 US8367805B2 (en) 2004-11-12 2008-12-22 Fc variants with altered binding to FcRn
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Cited By (39)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9657106B2 (en) 2003-03-03 2017-05-23 Xencor, Inc. Optimized Fc variants
US9803023B2 (en) 2004-11-12 2017-10-31 Xencor, Inc. Fc variants with altered binding to FcRn
WO2018045110A1 (en) * 2016-08-30 2018-03-08 Xencor, Inc. Bispecific immunomodulatory antibodies that bind costimulatory and checkpoint receptors
WO2019036419A1 (en) 2017-08-15 2019-02-21 Kalnik Matthew W Novel nicotine-binding antibodies
WO2018048941A3 (en) * 2016-09-08 2019-04-25 The Board Of Trustees Of The Leland Stanford Junior University Methods to increase the duration of action of therapeutic monoclonal antibody products
CN110267990A (en) * 2016-08-30 2019-09-20 Xencor股份有限公司 Bispecific immunomodulatory antibodies that bind co-stimulatory and checkpoint receptors
WO2019236665A1 (en) 2018-06-06 2019-12-12 Antidote Therapeutics, Inc. Methods for improving circulation and treating cardiovascular disease
WO2020092202A2 (en) 2018-10-29 2020-05-07 Biogen Ma Inc. Humanized and stabilized fc5 variants for enhancement of blood brain barrier transport
US10738133B2 (en) 2013-01-14 2020-08-11 Xencor, Inc. Heterodimeric proteins
US10787518B2 (en) 2016-06-14 2020-09-29 Xencor, Inc. Bispecific checkpoint inhibitor antibodies
US10793632B2 (en) 2016-08-30 2020-10-06 Xencor, Inc. Bispecific immunomodulatory antibodies that bind costimulatory and checkpoint receptors
US10858417B2 (en) 2013-03-15 2020-12-08 Xencor, Inc. Heterodimeric proteins
US10889653B2 (en) 2014-11-26 2021-01-12 Xencor, Inc. Heterodimeric antibodies that bind CD3 and tumor antigens
US10968276B2 (en) 2013-03-12 2021-04-06 Xencor, Inc. Optimized anti-CD3 variable regions
US10982006B2 (en) 2018-04-04 2021-04-20 Xencor, Inc. Heterodimeric antibodies that bind fibroblast activation protein
US10981992B2 (en) 2017-11-08 2021-04-20 Xencor, Inc. Bispecific immunomodulatory antibodies that bind costimulatory and checkpoint receptors
US11053316B2 (en) 2013-01-14 2021-07-06 Xencor, Inc. Optimized antibody variable regions
US11111315B2 (en) 2014-11-26 2021-09-07 Xencor, Inc. Heterodimeric antibodies that bind CD3 and tumor antigens
US11225521B2 (en) 2016-06-28 2022-01-18 Xencor, Inc. Heterodimeric antibodies that bind somatostatin receptor 2
US11299554B2 (en) 2013-03-15 2022-04-12 Xencor, Inc. Heterodimeric proteins
US11312770B2 (en) 2017-11-08 2022-04-26 Xencor, Inc. Bispecific and monospecific antibodies using novel anti-PD-1 sequences
US11319355B2 (en) 2017-12-19 2022-05-03 Xencor, Inc. Engineered IL-2 Fc fusion proteins
US11352442B2 (en) 2014-11-26 2022-06-07 Xencor, Inc. Heterodimeric antibodies that bind CD3 and CD38
US11358999B2 (en) 2018-10-03 2022-06-14 Xencor, Inc. IL-12 heterodimeric Fc-fusion proteins
US11401348B2 (en) 2009-09-02 2022-08-02 Xencor, Inc. Heterodimeric Fc variants
US11472890B2 (en) 2019-03-01 2022-10-18 Xencor, Inc. Heterodimeric antibodies that bind ENPP3 and CD3
US11505595B2 (en) 2018-04-18 2022-11-22 Xencor, Inc. TIM-3 targeted heterodimeric fusion proteins containing IL-15/IL-15RA Fc-fusion proteins and TIM-3 antigen binding domains
US11524991B2 (en) 2018-04-18 2022-12-13 Xencor, Inc. PD-1 targeted heterodimeric fusion proteins containing IL-15/IL-15Ra Fc-fusion proteins and PD-1 antigen binding domains and uses thereof
US11591401B2 (en) 2020-08-19 2023-02-28 Xencor, Inc. Anti-CD28 compositions
WO2023031615A1 (en) 2021-09-02 2023-03-09 Djs Antibodies Ltd Polypeptides
US11623957B2 (en) 2015-12-07 2023-04-11 Xencor, Inc. Heterodimeric antibodies that bind CD3 and PSMA
US11739144B2 (en) 2021-03-09 2023-08-29 Xencor, Inc. Heterodimeric antibodies that bind CD3 and CLDN6
US11840579B2 (en) 2014-03-28 2023-12-12 Xencor, Inc. Bispecific antibodies that bind to CD38 and CD3
US11859012B2 (en) 2021-03-10 2024-01-02 Xencor, Inc. Heterodimeric antibodies that bind CD3 and GPC3
US11919956B2 (en) 2020-05-14 2024-03-05 Xencor, Inc. Heterodimeric antibodies that bind prostate specific membrane antigen (PSMA) and CD3
WO2024048683A1 (en) 2022-08-30 2024-03-07 ミラバイオロジクス株式会社 Artificial protein and pharmaceutical composition
US11932685B2 (en) 2007-10-31 2024-03-19 Xencor, Inc. Fc variants with altered binding to FcRn
US12466897B2 (en) 2011-10-10 2025-11-11 Xencor, Inc. Heterodimeric human IgG1 polypeptides with isoelectric point modifications
US12492253B1 (en) 2008-02-25 2025-12-09 Xencor, Inc. Anti-human C5 antibodies

Families Citing this family (46)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20040132101A1 (en) 2002-09-27 2004-07-08 Xencor Optimized Fc variants and methods for their generation
US8367805B2 (en) * 2004-11-12 2013-02-05 Xencor, Inc. Fc variants with altered binding to FcRn
US8802820B2 (en) * 2004-11-12 2014-08-12 Xencor, Inc. Fc variants with altered binding to FcRn
US20220281964A1 (en) * 2008-02-25 2022-09-08 Xencor, Inc. Fc VARIANTS WITH ALTERED BINDING TO FcRn
FR2976811A1 (en) 2011-06-22 2012-12-28 Lfb Biotechnologies USE OF A HIGH ADCC ANTI-CD20 ANTIBODY FOR THE TREATMENT OF WALDENSTROM'S DISEASE
US9603897B2 (en) 2012-03-12 2017-03-28 Massachusetts Institute Of Technology Methods for treating tissue damage associated with ischemia with apolipoprotein D
US9738722B2 (en) 2013-01-15 2017-08-22 Xencor, Inc. Rapid clearance of antigen complexes using novel antibodies
EP3421495A3 (en) 2013-03-15 2019-05-15 Xencor, Inc. Modulation of t cells with bispecific antibodies and fc fusions
WO2016014984A1 (en) 2014-07-24 2016-01-28 Xencor, Inc. Rapid clearance of antigen complexes using novel antibodies
EP3945096A1 (en) 2014-12-19 2022-02-02 Regenesance B.V. Antibodies that bind human c6 and uses thereof
US10227411B2 (en) 2015-03-05 2019-03-12 Xencor, Inc. Modulation of T cells with bispecific antibodies and FC fusions
EP3302532A4 (en) 2015-06-05 2019-01-09 New York University COMPOSITIONS AND METHODS RELATED TO ANTISTAPHYLOCOCCAL BIOLOGICAL AGENTS
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BR112019001989A2 (en) 2016-08-02 2019-08-20 Visterra, Inc. engineered polypeptides and uses thereof
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CN111032688A (en) * 2017-08-11 2020-04-17 研究发展基金会 Engineered antibody FC variants for extended serum half-life
US20200040103A1 (en) 2018-03-14 2020-02-06 Genentech, Inc. Anti-klk5 antibodies and methods of use
WO2019235426A1 (en) * 2018-06-04 2019-12-12 中外製薬株式会社 Antigen-binding molecule showing changed half-life in cytoplasm
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CR20200653A (en) 2018-07-03 2021-02-11 Gilead Sciences Inc ANTIBODIES TARGETING HIV GP120 AND METHODS OF USE
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EP4072588A4 (en) 2019-12-13 2024-02-14 Cugene Inc. Novel interleukin-15 (il-15) fusion proteins and uses thereof
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CA3175921A1 (en) 2020-04-17 2021-10-21 Zoetis Services Llc Canine antibody variants
US11634477B2 (en) * 2020-04-28 2023-04-25 The Rockefeller University Neutralizing anti-SARS-CoV-2 antibodies and methods of use thereof
US20230250155A1 (en) 2020-06-29 2023-08-10 Zoetis Services Llc Feline antibody variants for improving stability
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WO2022010912A1 (en) 2020-07-06 2022-01-13 Flagship Pioneering Innovations Vi, Llc Antigen binding molecules targeting sars-cov-2
WO2022010652A1 (en) * 2020-07-10 2022-01-13 Invetx Inc. Compositions for increasing half-life of a therapeutic agent in felines and methods of use
IL300256A (en) 2020-08-25 2023-03-01 Gilead Sciences Inc Multi-specific antigen binding molecules targeting hiv and methods of use
KR20230058434A (en) 2020-08-26 2023-05-03 플래그쉽 파이어니어링 이노베이션스 브이아이, 엘엘씨 Antigen binding molecules targeting SARS-CoV-2
AR123636A1 (en) 2020-09-28 2022-12-28 Zoetis Services Llc VARIANTS OF CANINE ANTIBODIES
TWI814094B (en) 2020-09-29 2023-09-01 美商碩騰服務公司 Feline antibody variants
WO2022109313A1 (en) 2020-11-20 2022-05-27 Zoetis Services Llc Bovine antibody variants
US20240400708A1 (en) 2020-12-18 2024-12-05 Zoetis Services Llc Mutations in feline antibody constant regions
PE20231919A1 (en) 2021-01-28 2023-11-28 Zoetis Services Llc MUTATIONS IN CANINE ANTIBODIES CONSTANT REGIONS
WO2023244276A2 (en) * 2021-10-13 2023-12-21 The Wistar Institute Of Anatomy And Biology DNA ENCODED ANTIBODIES WITH Fc MODIFICATIONS
JP2024539139A (en) 2021-10-20 2024-10-28 シンセカイン インコーポレイテッド Heterodimeric FC cytokines and uses thereof
US20250084169A1 (en) 2022-01-12 2025-03-13 Biomolecular Holdings Llc Nk/monocyte engagers
WO2023215910A1 (en) 2022-05-06 2023-11-09 Generate Biomedicines, Inc. Antigen binding molecules targeting sars-cov-2
US12319742B1 (en) 2024-01-24 2025-06-03 Shattuck Labs, Inc. Antibodies that bind TNFRSF25
WO2025160334A1 (en) 2024-01-26 2025-07-31 Flagship Pioneering Innovations Vii, Llc Immunoreceptor inhibitory proteins and related methods
US20250353881A1 (en) 2024-05-16 2025-11-20 Flagship Pioneering Innovations Vii, Llc Immunoreceptor inhibitory proteins and related methods
US20260015407A1 (en) 2024-07-15 2026-01-15 Flagship Pioneering Innovations Vii, Llc Immunomodulatory fusion proteins and related methods

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8324351B2 (en) * 2004-11-12 2012-12-04 Xencor, Inc. Fc variants with altered binding to FcRn

Family Cites Families (204)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3773919A (en) 1969-10-23 1973-11-20 Du Pont Polylactide-drug mixtures
CU22545A1 (en) 1994-11-18 1999-03-31 Centro Inmunologia Molecular OBTAINING A CHEMICAL AND HUMANIZED ANTIBODY AGAINST THE RECEPTOR OF THE EPIDERMAL GROWTH FACTOR FOR DIAGNOSTIC AND THERAPEUTIC USE
US4485045A (en) 1981-07-06 1984-11-27 Research Corporation Synthetic phosphatidyl cholines useful in forming liposomes
GB8308235D0 (en) 1983-03-25 1983-05-05 Celltech Ltd Polypeptides
US4816567A (en) 1983-04-08 1989-03-28 Genentech, Inc. Recombinant immunoglobin preparations
US4544545A (en) 1983-06-20 1985-10-01 Trustees University Of Massachusetts Liposomes containing modified cholesterol for organ targeting
US4753894A (en) 1984-02-08 1988-06-28 Cetus Corporation Monoclonal anti-human breast cancer antibodies
US4943533A (en) 1984-03-01 1990-07-24 The Regents Of The University Of California Hybrid cell lines that produce monoclonal antibodies to epidermal growth factor receptor
US6548640B1 (en) 1986-03-27 2003-04-15 Btg International Limited Altered antibodies
US5225539A (en) 1986-03-27 1993-07-06 Medical Research Council Recombinant altered antibodies and methods of making altered antibodies
NZ220504A (en) 1986-05-29 1991-09-25 Univ Melbourne Fc receptor site an immunoglobulin and dna sequences encodng it
IL85035A0 (en) 1987-01-08 1988-06-30 Int Genetic Eng Polynucleotide molecule,a chimeric antibody with specificity for human b cell surface antigen,a process for the preparation and methods utilizing the same
WO1988007089A1 (en) 1987-03-18 1988-09-22 Medical Research Council Altered antibodies
US4975278A (en) 1988-02-26 1990-12-04 Bristol-Myers Company Antibody-enzyme conjugates in combination with prodrugs for the delivery of cytotoxic agents to tumor cells
PT88641B (en) 1987-10-02 1993-04-30 Genentech Inc METHOD FOR PREPARING A VARIETY OF ADHESION
WO1989006692A1 (en) 1988-01-12 1989-07-27 Genentech, Inc. Method of treating tumor cells by inhibiting growth factor receptor function
US5576184A (en) 1988-09-06 1996-11-19 Xoma Corporation Production of chimeric mouse-human antibodies with specificity to human tumor antigens
US5681566A (en) 1988-10-24 1997-10-28 3I Research Exploitation Limited Antibody conjugates with two or more covalently linked FC regions
US5530101A (en) 1988-12-28 1996-06-25 Protein Design Labs, Inc. Humanized immunoglobulins
US20040049014A1 (en) 1988-12-28 2004-03-11 Protein Design Labs, Inc. Humanized immunoglobulins
JP3051411B2 (en) 1989-03-14 2000-06-12 持田製薬株式会社 Novel DNA and expression plasmid containing it
US5266491A (en) 1989-03-14 1993-11-30 Mochida Pharmaceutical Co., Ltd. DNA fragment and expression plasmid containing the DNA fragment
US5208020A (en) 1989-10-25 1993-05-04 Immunogen Inc. Cytotoxic agents comprising maytansinoids and their therapeutic use
EP0462246A4 (en) 1989-11-07 1992-11-25 Bristol-Myers Squibb Company Oligomeric immunoglobulins
US5859205A (en) 1989-12-21 1999-01-12 Celltech Limited Humanised antibodies
WO1991019515A1 (en) 1990-06-21 1991-12-26 The Board Of Trustees Of The Leland Stanford Junior University Oligomeric immunoglobulin constant domain mutant with enhanced complement-mediated cytolytic activity
US5198342A (en) 1990-07-05 1993-03-30 Immunex Corporation DNA encoding IgA Fc receptors
AU8506991A (en) 1990-08-31 1992-03-30 Bristol-Myers Squibb Company Homoconjugated immunoglobulins
GB9022545D0 (en) 1990-10-17 1990-11-28 Wellcome Found Culture medium
DE69233153T2 (en) 1991-03-06 2004-05-27 Merck Patent Gmbh HUMANIZED MONOCLONAL ANTIBODIES
GB9105245D0 (en) 1991-03-12 1991-04-24 Lynxvale Ltd Binding molecules
US6797492B2 (en) 1991-05-17 2004-09-28 Merck & Co., Inc. Method for reducing the immunogenicity of antibody variable domains
WO1994004679A1 (en) 1991-06-14 1994-03-03 Genentech, Inc. Method for making humanized antibodies
JP4124480B2 (en) 1991-06-14 2008-07-23 ジェネンテック・インコーポレーテッド Immunoglobulin variants
EP0590067A1 (en) 1991-06-14 1994-04-06 Xoma Corporation Microbially-produced antibody fragments and their conjugates
US5264586A (en) 1991-07-17 1993-11-23 The Scripps Research Institute Analogs of calicheamicin gamma1I, method of making and using the same
IE922437A1 (en) 1991-07-25 1993-01-27 Idec Pharma Corp Recombinant antibodies for human therapy
US6329509B1 (en) 1991-08-14 2001-12-11 Genentech, Inc. Anti-IgE antibodies
WO1993006217A1 (en) 1991-09-19 1993-04-01 Genentech, Inc. EXPRESSION IN E. COLI OF ANTIBODY FRAGMENTS HAVING AT LEAST A CYSTEINE PRESENT AS A FREE THIOL, USE FOR THE PRODUCTION OF BIFUNCTIONAL F(ab')2 ANTIBODIES
US5623053A (en) 1992-01-10 1997-04-22 California Institute Of Technology Soluble mammal-derived Fc receptor which binds at a pH ranging from about 5.5 to 6.5 and releases at a pH ranging from about 7.5 to 8.5
US5714350A (en) 1992-03-09 1998-02-03 Protein Design Labs, Inc. Increasing antibody affinity by altering glycosylation in the immunoglobulin variable region
AU4116793A (en) 1992-04-24 1993-11-29 Board Of Regents, The University Of Texas System Recombinant production of immunoglobulin-like domains in prokaryotic cells
US5736137A (en) 1992-11-13 1998-04-07 Idec Pharmaceuticals Corporation Therapeutic application of chimeric and radiolabeled antibodies to human B lymphocyte restricted differentiation antigen for treatment of B cell lymphoma
US20030108548A1 (en) 1993-06-01 2003-06-12 Bluestone Jeffrey A. Methods and materials for modulation of the immunosuppressive activity and toxicity of monoclonal antibodies
US5885573A (en) 1993-06-01 1999-03-23 Arch Development Corporation Methods and materials for modulation of the immunosuppressive activity and toxicity of monoclonal antibodies
CA2163345A1 (en) 1993-06-16 1994-12-22 Susan Adrienne Morgan Antibodies
GB9316989D0 (en) 1993-08-16 1993-09-29 Lynxvale Ltd Binding molecules
CA2186455A1 (en) 1994-03-29 1995-10-05 Raymond John Owens Antibodies against e-selectin
US5773001A (en) 1994-06-03 1998-06-30 American Cyanamid Company Conjugates of methyltrithio antitumor agents and intermediates for their synthesis
US5541087A (en) 1994-09-14 1996-07-30 Fuji Immunopharmaceuticals Corporation Expression and export technology of proteins as immunofusins
US5804396A (en) 1994-10-12 1998-09-08 Sugen, Inc. Assay for agents active in proliferative disorders
US6030613A (en) 1995-01-17 2000-02-29 The Brigham And Women's Hospital, Inc. Receptor specific transepithelial transport of therapeutics
JP4026848B2 (en) 1995-01-17 2007-12-26 ブリガーム・アンド・ウーメンズ・ホスピタル・インコーポレーテッド Receptor-specific transepithelial transport of immunogens
US6086875A (en) 1995-01-17 2000-07-11 The Brigham And Women's Hospital, Inc. Receptor specific transepithelial transport of immunogens
US6485726B1 (en) 1995-01-17 2002-11-26 The Brigham And Women's Hospital, Inc. Receptor specific transepithelial transport of therapeutics
US5731168A (en) 1995-03-01 1998-03-24 Genentech, Inc. Method for making heteromultimeric polypeptides
US6121022A (en) 1995-04-14 2000-09-19 Genentech, Inc. Altered polypeptides with increased half-life
US6444789B1 (en) 1995-05-03 2002-09-03 Applied Research Systems Ars Holding N.V. CD16-II variants
US6365161B1 (en) 1995-06-07 2002-04-02 Medarex, Inc. Therapeutic compounds comprised of anti-FC receptor binding agents
US5714586A (en) 1995-06-07 1998-02-03 American Cyanamid Company Methods for the preparation of monomeric calicheamicin derivative/carrier conjugates
US5712374A (en) 1995-06-07 1998-01-27 American Cyanamid Company Method for the preparation of substantiallly monomeric calicheamicin derivative/carrier conjugates
US6750334B1 (en) 1996-02-02 2004-06-15 Repligen Corporation CTLA4-immunoglobulin fusion proteins having modified effector functions and uses therefor
CA2249195A1 (en) 1996-03-18 1997-09-25 Board Of Regents, The University Of Texas System Immunoglobin-like domains with increased half lives
JP3904238B2 (en) 1996-03-20 2007-04-11 イムノメディクス， インコーポレイテッド Glycosylated humanized B cell specific antibody
US5834597A (en) 1996-05-20 1998-11-10 Protein Design Labs, Inc. Mutated nonactivating IgG2 domains and anti CD3 antibodies incorporating the same
DE69726003T2 (en) 1996-07-16 2004-08-26 Andreas Plückthun IMMUNGLOBULIN SUPERFAMILY DOMAINS AND FRAGMENTS WITH INCREASED SOLUBILITY
DE69738522T2 (en) 1996-08-02 2009-04-02 Bristol-Myers Squibb Co. A METHOD FOR INHIBITING IMMUNOGLOBINENE IN IMMUNOGLOBINS IN THERAPY AND IN VIVO DIAGNOSTIC IMMUNOGLOBININE-INDUCED TOXICITY
WO1998023289A1 (en) 1996-11-27 1998-06-04 The General Hospital Corporation MODULATION OF IgG BINDING TO FcRn
CA2278154A1 (en) 1997-01-21 1998-07-23 Human Genome Sciences, Inc. Fc receptors and polypeptides
US6277375B1 (en) 1997-03-03 2001-08-21 Board Of Regents, The University Of Texas System Immunoglobulin-like domains with increased half-lives
DE69810603T2 (en) 1997-04-11 2003-11-13 California Inst Of Techn DEVICE AND METHOD FOR AUTOMATIC PROTEIN DESIGN
EP1255209A3 (en) 1997-04-11 2009-02-11 California Institute Of Technology Apparatus and method for automated protein design
US20020062010A1 (en) 1997-05-02 2002-05-23 Genentech, Inc. Method for making multispecific antibodies having heteromultimeric and common components
US6235883B1 (en) 1997-05-05 2001-05-22 Abgenix, Inc. Human monoclonal antibodies to epidermal growth factor receptor
US20040191256A1 (en) 1997-06-24 2004-09-30 Genentech, Inc. Methods and compositions for galactosylated glycoproteins
US20030105294A1 (en) 1998-02-25 2003-06-05 Stephen Gillies Enhancing the circulating half life of antibody-based fusion proteins
US6194551B1 (en) 1998-04-02 2001-02-27 Genentech, Inc. Polypeptide variants
US6242195B1 (en) 1998-04-02 2001-06-05 Genentech, Inc. Methods for determining binding of an analyte to a receptor
US6528624B1 (en) 1998-04-02 2003-03-04 Genentech, Inc. Polypeptide variants
ATE375365T1 (en) 1998-04-02 2007-10-15 Genentech Inc ANTIBODIES VARIANTS AND FRAGMENTS THEREOF
PT1071700E (en) 1998-04-20 2010-04-23 Glycart Biotechnology Ag Glycosylation engineering of antibodies for improving antibody-dependent cellular cytotoxicity
WO1999054484A1 (en) 1998-04-20 1999-10-28 The Regents Of The University Of California Modified immunoglobulin molecules and methods for use thereof
AU3871099A (en) 1998-05-06 1999-11-23 Temple University - Of The Commonwealth System Of Higher Education Reversal of proinflammatory response by ligating the macrophage fcgammari receptor
GB9809951D0 (en) 1998-05-08 1998-07-08 Univ Cambridge Tech Binding molecules
AU770555B2 (en) 1998-08-17 2004-02-26 Abgenix, Inc. Generation of modified molecules with increased serum half-lives
US6306926B1 (en) 1998-10-07 2001-10-23 3M Innovative Properties Company Radiopaque cationically polymerizable compositions comprising a radiopacifying filler, and method for polymerizing same
US7315786B2 (en) 1998-10-16 2008-01-01 Xencor Protein design automation for protein libraries
US20020048772A1 (en) 2000-02-10 2002-04-25 Dahiyat Bassil I. Protein design automation for protein libraries
US20030049654A1 (en) 1998-10-16 2003-03-13 Xencor Protein design automation for protein libraries
US6403312B1 (en) 1998-10-16 2002-06-11 Xencor Protein design automatic for protein libraries
WO2000023564A2 (en) 1998-10-16 2000-04-27 Xencor, Inc. Protein design automation for protein libraries
US6660843B1 (en) 1998-10-23 2003-12-09 Amgen Inc. Modified peptides as therapeutic agents
US6737056B1 (en) 1999-01-15 2004-05-18 Genentech, Inc. Polypeptide variants with altered effector function
EP1141024B1 (en) 1999-01-15 2018-08-08 Genentech, Inc. POLYPEPTIDE COMPRISING A VARIANT HUMAN IgG1 Fc REGION
US6221556B1 (en) 1999-03-05 2001-04-24 General Electric Company Article for optical data storage device
ES2601882T5 (en) 1999-04-09 2021-06-07 Kyowa Kirin Co Ltd Procedure to monitor the activity of an immunofunctional molecule
US6663862B1 (en) 1999-06-04 2003-12-16 Duke University Reagents for detection and purification of antibody fragments
US6638515B2 (en) 1999-09-07 2003-10-28 Walter Schubert Method of blocking cytotoxic activity in patients with amyotrophic lateral sclerosis using protein V
CA2388245C (en) 1999-10-19 2012-01-10 Tatsuya Ogawa The use of serum-free adapted rat cells for producing heterologous polypeptides
EP2363403B1 (en) 1999-11-29 2016-04-20 The Trustees of Columbia University in the City of New York Isolation of five novel genes coding for new fc receptors-type melanoma involved in the pathogenesis of lymphoma/melanoma
CN1163506C (en) 1999-12-10 2004-08-25 上海华晨生物技术研究所 New human cell factor and its code sequence and use
WO2001057088A1 (en) 2000-02-03 2001-08-09 Hammarstroem Lennart RUMINANT MHC CLASS I-LIKE Fc RECEPTORS
EP1255826B1 (en) 2000-02-10 2005-09-14 Xencor Protein design automation for protein libraries
AU3495301A (en) 2000-02-11 2001-08-20 Biogen Inc Heterologous polypeptide of the tnf family
US7101974B2 (en) 2000-03-02 2006-09-05 Xencor TNF-αvariants
US7244823B2 (en) 2000-03-02 2007-07-17 Xencor TNF-alpha variants proteins for the treatment of TNF-alpha related disorders
US7056695B2 (en) 2000-03-02 2006-06-06 Xencor TNF-α variants
US7687461B2 (en) 2000-03-02 2010-03-30 Xencor, Inc. Treatment of TNF-α related disorders with TNF-α variant proteins
DK2857516T3 (en) 2000-04-11 2017-08-07 Genentech Inc Multivalent antibodies and uses thereof
JP2003531149A (en) 2000-04-13 2003-10-21 ザ・ロツクフエラー・ユニバーシテイ Enhancement of antibody-derived immune response
US6358733B1 (en) 2000-05-19 2002-03-19 Apolife, Inc. Expression of heterologous multi-domain proteins in yeast
WO2002005146A2 (en) 2000-07-10 2002-01-17 Xencor, Inc. Method for disigning protein libraries with altered immunogenicity
US20030068649A1 (en) 2000-09-14 2003-04-10 Doberstein Stephen K. Methods and compositions for the construction and use of fusion libraries
US7064191B2 (en) 2000-10-06 2006-06-20 Kyowa Hakko Kogyo Co., Ltd. Process for purifying antibody
JPWO2002030954A1 (en) 2000-10-06 2004-02-19 協和醗酵工業株式会社 Methods for purifying antibodies
HU231090B1 (en) 2000-10-06 2020-07-28 Kyowa Kirin Co., Ltd. Cells producing antibody compositions
US6946292B2 (en) 2000-10-06 2005-09-20 Kyowa Hakko Kogyo Co., Ltd. Cells producing antibody compositions with increased antibody dependent cytotoxic activity
US7465790B2 (en) 2000-10-09 2008-12-16 Isis Innovation, Inc. Therapeutic antibodies
WO2002043658A2 (en) 2000-11-06 2002-06-06 The Jackson Laboratory Fcrn-based therapeutics for the treatment of auto-immune disorders
US7235643B2 (en) 2000-11-07 2007-06-26 Morphotek, Inc. Antibodies and methods for generating genetically altered antibodies with high affinity
GB0029407D0 (en) 2000-12-01 2001-01-17 Affitech As Product
US20040253242A1 (en) 2000-12-05 2004-12-16 Bowdish Katherine S. Rationally designed antibodies
EP1355919B1 (en) 2000-12-12 2010-11-24 MedImmune, LLC Molecules with extended half-lives, compositions and uses thereof
WO2002066653A2 (en) 2000-12-14 2002-08-29 Xencor Procaryotic libraries and uses
ATE405650T1 (en) 2000-12-14 2008-09-15 Genentech Inc PRODUCTION OF WHOLE ANTIBODIES IN PROKARYONTIC CELLS
US6979556B2 (en) 2000-12-14 2005-12-27 Genentech, Inc. Separate-cistron contructs for secretion of aglycosylated antibodies from prokaryotes
US20030133939A1 (en) 2001-01-17 2003-07-17 Genecraft, Inc. Binding domain-immunoglobulin fusion proteins
US7754208B2 (en) 2001-01-17 2010-07-13 Trubion Pharmaceuticals, Inc. Binding domain-immunoglobulin fusion proteins
WO2002061093A1 (en) 2001-01-30 2002-08-08 Degussa Ag Nucleotide sequences which code for the otsa gene of c. glutamicum
US20020168640A1 (en) 2001-02-22 2002-11-14 Min Li Biochips comprising nucleic acid/protein conjugates
JP2005500018A (en) 2001-04-02 2005-01-06 アイデック ファーマスーティカルズ コーポレイション Recombinant antibody coexpressed with GnTIII
US7117096B2 (en) 2001-04-17 2006-10-03 Abmaxis, Inc. Structure-based selection and affinity maturation of antibody library
CN100497389C (en) 2001-06-13 2009-06-10 根马布股份公司 Human monoclonal antibodies to epidermal growth factor receptor (EGFR)
GB0118662D0 (en) 2001-07-31 2001-09-19 Univ Southampton Binding agents
EP1423510A4 (en) 2001-08-03 2005-06-01 Glycart Biotechnology Ag ANTIBODY GLYCOSYLATION VARIANTS WITH INCREASED CELL CYTOTOXICITY DEPENDENT OF ANTIBODIES
WO2003016470A2 (en) 2001-08-10 2003-02-27 University Of Virginia Patent Foundation Enhancing the efficacy of immunotherapies by supplementing with complement
WO2003014325A2 (en) 2001-08-10 2003-02-20 Xencor Protein design automation for protein libraries
HUP0600342A3 (en) 2001-10-25 2011-03-28 Genentech Inc Glycoprotein compositions
US6911321B2 (en) 2001-12-19 2005-06-28 Genentech, Inc. Non-human primate Fc receptors and methods of use
US20040093621A1 (en) 2001-12-25 2004-05-13 Kyowa Hakko Kogyo Co., Ltd Antibody composition which specifically binds to CD20
US20030224397A1 (en) 2002-02-11 2003-12-04 Genentech, Inc. Antibody variants with faster antigen association rates
US20040002587A1 (en) 2002-02-20 2004-01-01 Watkins Jeffry D. Fc region variants
AU2003217912A1 (en) 2002-03-01 2003-09-16 Xencor Antibody optimization
US20070122406A1 (en) 2005-07-08 2007-05-31 Xencor, Inc. Optimized proteins that target Ep-CAM
US8093357B2 (en) 2002-03-01 2012-01-10 Xencor, Inc. Optimized Fc variants and methods for their generation
US7317091B2 (en) 2002-03-01 2008-01-08 Xencor, Inc. Optimized Fc variants
US20040132101A1 (en) 2002-09-27 2004-07-08 Xencor Optimized Fc variants and methods for their generation
EP1487992A4 (en) 2002-03-15 2007-10-31 Brigham & Womens Hospital CENTRAL AIRWAY DELIVERY FOR SYSTEMIC DRUG DELIVERY
EP1490085A2 (en) 2002-03-25 2004-12-29 Uab Research Foundation Fc receptor homolog, reagents, and uses thereof
WO2003085119A1 (en) 2002-04-09 2003-10-16 Kyowa Hakko Kogyo Co., Ltd. METHOD OF ENHANCING ACTIVITY OF ANTIBODY COMPOSITION OF BINDING TO FcϜ RECEPTOR IIIa
CA2491129A1 (en) 2002-07-03 2004-01-15 Brigham And Women's Hospital, Inc. Central airway administration for systemic delivery of therapeutics
WO2004004662A2 (en) 2002-07-09 2004-01-15 Genentech, Inc. Compositions and methods for the diagnosis and treatment of tumor
ES2381617T5 (en) 2002-08-14 2016-02-24 Macrogenics, Inc. Specific antibodies against FcgammaRIIB and its procedures for use
AU2003270369A1 (en) 2002-09-05 2004-03-29 The Government Of The United States Of America As Represented By The Secretary Of The Department Of Health And Human Services Minimally immunogenic variants of humanized col-1 antibody against carcinoembryonic antigen
EP1539811A4 (en) 2002-09-16 2006-05-24 Elusys Therapeutics Inc Production of bispecific molecules using polyethylene glycol linkers
US20060235208A1 (en) 2002-09-27 2006-10-19 Xencor, Inc. Fc variants with optimized properties
US7217797B2 (en) 2002-10-15 2007-05-15 Pdl Biopharma, Inc. Alteration of FcRn binding affinities or serum half-lives of antibodies by mutagenesis
US7365168B2 (en) 2002-10-15 2008-04-29 Pdl Biopharma, Inc. Alteration of FcRn binding affinities or serum half-lives of antibodies by mutagenesis
US7361740B2 (en) 2002-10-15 2008-04-22 Pdl Biopharma, Inc. Alteration of FcRn binding affinities or serum half-lives of antibodies by mutagenesis
ATE480562T1 (en) 2002-10-15 2010-09-15 Facet Biotech Corp CHANGE IN FCRN BINDING AFFINITIES OR SERUM HALF-LIFE TIMES OF ANTIBODIES USING MUtagenesis
DK2289936T3 (en) 2002-12-16 2017-07-31 Genentech Inc IMMUNGLOBULIN VARIATIONS AND APPLICATIONS THEREOF
US7960512B2 (en) 2003-01-09 2011-06-14 Macrogenics, Inc. Identification and engineering of antibodies with variant Fc regions and methods of using same
AU2004204494B2 (en) 2003-01-09 2011-09-29 Macrogenics, Inc. Identification and engineering of antibodies with variant Fc regions and methods of using same
US8388955B2 (en) 2003-03-03 2013-03-05 Xencor, Inc. Fc variants
WO2004087752A2 (en) 2003-04-04 2004-10-14 Ingenium Pharmaceuticals Ag Spinster-like protein genes, expression products, non-human animal model: uses in human metabolic disorders
TWI353991B (en) 2003-05-06 2011-12-11 Syntonix Pharmaceuticals Inc Immunoglobulin chimeric monomer-dimer hybrids
AR044388A1 (en) 2003-05-20 2005-09-07 Applied Molecular Evolution CD20 UNION MOLECULES
CA2527878A1 (en) 2003-05-30 2005-01-27 Alexion Pharmaceuticals, Inc. Antibodies and fusion proteins that include engineered constant regions
US20070253966A1 (en) 2003-06-12 2007-11-01 Eli Lilly And Company Fusion Proteins
US20040254108A1 (en) 2003-06-13 2004-12-16 Jing Ma Preparation and application of anti-tumor bifunctional fusion proteins
CA2530388A1 (en) 2003-06-27 2005-01-06 Biogen Idec Ma Inc. Modified binding molecules comprising connecting peptides
US20050033029A1 (en) 2003-06-30 2005-02-10 Jin Lu Engineered anti-target immunoglobulin derived proteins, compositions, methods and uses
CN104645327A (en) 2003-07-24 2015-05-27 依奈特制药公司 Methods and compositions for increasing the efficiency of therapeutic antibodies using NK cell potentiating compounds
CA2533593A1 (en) 2003-07-26 2005-02-10 Biogen Idec Ma Inc. Altered antibodies having improved antigen-binding affinity
US20080050357A1 (en) 2003-08-01 2008-02-28 Claes Gustafsson Systems and Methods for Antibody Engineering
AU2004266159A1 (en) 2003-08-22 2005-03-03 Biogen Idec Ma Inc. Improved antibodies having altered effector function and methods for making the same
US20050152894A1 (en) 2003-09-05 2005-07-14 Genentech, Inc. Antibodies with altered effector functions
US7348401B2 (en) 2003-09-10 2008-03-25 Innate Biotech, Inc. Peptides that inhibit complement activation
EP1673395A1 (en) 2003-10-15 2006-06-28 PDL BioPharma, Inc. Alteration of fc-fusion protein serum half-lives by mutagenesis of positions 250, 314 and/or 428 of the heavy chain constant region of ig
GB0324368D0 (en) 2003-10-17 2003-11-19 Univ Cambridge Tech Polypeptides including modified constant regions
WO2005063815A2 (en) 2003-11-12 2005-07-14 Biogen Idec Ma Inc. Fcϝ receptor-binding polypeptide variants and methods related thereto
CA2545603A1 (en) 2003-11-12 2005-05-26 Biogen Idec Ma Inc. Neonatal fc receptor (fcrn)-binding polypeptide variants, dimeric fc binding proteins and methods related thereto
AU2004297616B2 (en) 2003-12-04 2008-12-18 Xencor, Inc. Methods of generating variant proteins with increased host string content and compositions thereof
BRPI0506771A (en) 2004-01-12 2007-05-22 Applied Molecular Evolution antibody and pharmaceutical composition
EP1737890A2 (en) 2004-03-24 2007-01-03 Xencor, Inc. Immunoglobulin variants outside the fc region
WO2005123780A2 (en) 2004-04-09 2005-12-29 Protein Design Labs, Inc. Alteration of fcrn binding affinities or serum half-lives of antibodies by mutagenesis
MXPA06012601A (en) 2004-05-10 2007-05-10 Macrogenics Inc HUMANIZED FcgammaRIIB SPECIFIC ANTIBODIES AND METHODS OF USE THEREOF.
KR100545720B1 (en) 2004-05-31 2006-01-24 메덱스젠 주식회사 Glycated immunoglobulins and immunoconjugates comprising them
US8008447B2 (en) 2004-07-23 2011-08-30 Genentech, Inc. Crystallization of antibody or fragment thereof
JP5055603B2 (en) 2004-08-04 2012-10-24 メントリック・バイオテック・リミテッド・ライアビリティ・カンパニー Mutated Fc region
JP2008510466A (en) 2004-08-19 2008-04-10 ジェネンテック・インコーポレーテッド Polypeptide variants with altered effector function
CA2587766A1 (en) 2004-11-10 2007-03-01 Macrogenics, Inc. Engineering fc antibody regions to confer effector function
AU2005304624B2 (en) 2004-11-12 2010-10-07 Xencor, Inc. Fc variants with altered binding to FcRn
US8163881B2 (en) 2005-05-31 2012-04-24 The Board Of Regents Of The University Of Texas System Immunoglobulin molecules with improved characteristics
DK2573114T3 (en) 2005-08-10 2016-07-04 Macrogenics Inc The identification and production of antibodies with variant Fc regions, and methods of using same
WO2007041635A2 (en) 2005-10-03 2007-04-12 Xencor, Inc. Fc variants with optimized fc receptor binding properties
AU2006304387A1 (en) 2005-10-14 2007-04-26 Medimmune, Llc Cell display of antibody libraries
US20070087005A1 (en) 2005-10-14 2007-04-19 Lazar Gregory A Anti-glypican-3 antibody
AU2007212147A1 (en) 2006-02-03 2007-08-16 Medimmune, Llc Protein formulations
US20100166741A1 (en) 2006-07-13 2010-07-01 Genentech , Inc. Altered br-3 binding polypeptides
US20080112961A1 (en) 2006-10-09 2008-05-15 Macrogenics, Inc. Identification and Engineering of Antibodies with Variant Fc Regions and Methods of Using Same
WO2008070780A1 (en) 2006-12-07 2008-06-12 Novartis Ag Antagonist antibodies against ephb3
WO2008140603A2 (en) 2006-12-08 2008-11-20 Macrogenics, Inc. METHODS FOR THE TREATMENT OF DISEASE USING IMMUNOGLOBULINS HAVING FC REGIONS WITH ALTERED AFFINITIES FOR FCγR ACTIVATING AND FCγR INHIBITING
WO2008079849A2 (en) 2006-12-22 2008-07-03 Genentech, Inc. Antibodies to insulin-like growth factor receptor

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8324351B2 (en) * 2004-11-12 2012-12-04 Xencor, Inc. Fc variants with altered binding to FcRn

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
Chan et al. Nature Review Immunology 2010, 10:301-316. *

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9657106B2 (en) 2003-03-03 2017-05-23 Xencor, Inc. Optimized Fc variants
US9803023B2 (en) 2004-11-12 2017-10-31 Xencor, Inc. Fc variants with altered binding to FcRn
US12215165B2 (en) 2004-11-12 2025-02-04 Xencor, Inc. Fc variants with altered binding to FcRn
US11932685B2 (en) 2007-10-31 2024-03-19 Xencor, Inc. Fc variants with altered binding to FcRn
US12492253B1 (en) 2008-02-25 2025-12-09 Xencor, Inc. Anti-human C5 antibodies
US11401348B2 (en) 2009-09-02 2022-08-02 Xencor, Inc. Heterodimeric Fc variants
US12466897B2 (en) 2011-10-10 2025-11-11 Xencor, Inc. Heterodimeric human IgG1 polypeptides with isoelectric point modifications
US11718667B2 (en) 2013-01-14 2023-08-08 Xencor, Inc. Optimized antibody variable regions
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US11053316B2 (en) 2013-01-14 2021-07-06 Xencor, Inc. Optimized antibody variable regions
US10968276B2 (en) 2013-03-12 2021-04-06 Xencor, Inc. Optimized anti-CD3 variable regions
US11299554B2 (en) 2013-03-15 2022-04-12 Xencor, Inc. Heterodimeric proteins
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US12415849B2 (en) 2013-03-15 2025-09-16 Xencor, Inc. Heterodimeric proteins
US11840579B2 (en) 2014-03-28 2023-12-12 Xencor, Inc. Bispecific antibodies that bind to CD38 and CD3
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US11236170B2 (en) 2016-06-14 2022-02-01 Xencor, Inc. Bispecific checkpoint inhibitor antibodies
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US12054545B2 (en) 2016-06-28 2024-08-06 Xencor, Inc. Heterodimeric antibodies that bind somatostatin receptor 2
WO2018045110A1 (en) * 2016-08-30 2018-03-08 Xencor, Inc. Bispecific immunomodulatory antibodies that bind costimulatory and checkpoint receptors
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US10793632B2 (en) 2016-08-30 2020-10-06 Xencor, Inc. Bispecific immunomodulatory antibodies that bind costimulatory and checkpoint receptors
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EP4624496A2 (en) 2017-08-15 2025-10-01 BliNK Biomedical SAS Novel nicotine-binding antibodies
WO2019036419A1 (en) 2017-08-15 2019-02-21 Kalnik Matthew W Novel nicotine-binding antibodies
US11440970B2 (en) 2017-08-15 2022-09-13 Antidote Therapeutics, Inc. Nicotine-binding antibodies
US11312770B2 (en) 2017-11-08 2022-04-26 Xencor, Inc. Bispecific and monospecific antibodies using novel anti-PD-1 sequences
US12152076B2 (en) 2017-11-08 2024-11-26 Xencor, Inc. Bispecific and monospecific antibodies using novel anti-PD-1 sequences
US10981992B2 (en) 2017-11-08 2021-04-20 Xencor, Inc. Bispecific immunomodulatory antibodies that bind costimulatory and checkpoint receptors
US11319355B2 (en) 2017-12-19 2022-05-03 Xencor, Inc. Engineered IL-2 Fc fusion proteins
US12180302B2 (en) 2018-04-04 2024-12-31 Xencor, Inc. Heterodimeric antibodies that bind fibroblast activation protein
US10982006B2 (en) 2018-04-04 2021-04-20 Xencor, Inc. Heterodimeric antibodies that bind fibroblast activation protein
US11505595B2 (en) 2018-04-18 2022-11-22 Xencor, Inc. TIM-3 targeted heterodimeric fusion proteins containing IL-15/IL-15RA Fc-fusion proteins and TIM-3 antigen binding domains
US11524991B2 (en) 2018-04-18 2022-12-13 Xencor, Inc. PD-1 targeted heterodimeric fusion proteins containing IL-15/IL-15Ra Fc-fusion proteins and PD-1 antigen binding domains and uses thereof
WO2019236665A1 (en) 2018-06-06 2019-12-12 Antidote Therapeutics, Inc. Methods for improving circulation and treating cardiovascular disease
US11358999B2 (en) 2018-10-03 2022-06-14 Xencor, Inc. IL-12 heterodimeric Fc-fusion proteins
WO2020092202A2 (en) 2018-10-29 2020-05-07 Biogen Ma Inc. Humanized and stabilized fc5 variants for enhancement of blood brain barrier transport
US11472890B2 (en) 2019-03-01 2022-10-18 Xencor, Inc. Heterodimeric antibodies that bind ENPP3 and CD3
US11919956B2 (en) 2020-05-14 2024-03-05 Xencor, Inc. Heterodimeric antibodies that bind prostate specific membrane antigen (PSMA) and CD3
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US11591401B2 (en) 2020-08-19 2023-02-28 Xencor, Inc. Anti-CD28 compositions
US11919958B2 (en) 2020-08-19 2024-03-05 Xencor, Inc. Anti-CD28 compositions
US12398207B2 (en) 2021-03-09 2025-08-26 Xencor, Inc. Heterodimeric antibodies that bind CD3 and CLDN6
US11739144B2 (en) 2021-03-09 2023-08-29 Xencor, Inc. Heterodimeric antibodies that bind CD3 and CLDN6
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