Search

EP-4741424-A2 - FC VARIANTS WITH ALTERED BINDING TO FCRN

EP4741424A2EP 4741424 A2EP4741424 A2EP 4741424A2EP-4741424-A2

Abstract

The present application relates to a variant Fc region comprising at least one modification relative to a wild-type human Fc region.

Inventors

  • CHAMBERLAIN, AARON
  • DAHIYAT, BASSIL
  • DESJARLAIS, JOHN RUDOLPH
  • KARKI, SHER BAHADUR
  • LAZAR, GREGORY ALAN

Assignees

  • Xencor, Inc.

Dates

Publication Date
20260513
Application Date
20081222

Claims (10)

  1. An anti-IgE antibody having a variable heavy domain comprising SEQ ID NO:21 and a variable light domain comprising SEQ ID NO:22, wherein said anti-IgE antibody comprises a variant Fc domain comprising the amino acid substitutions 428L/434S, wherein numbering is according to the EU index.
  2. A polypeptide comprising an Fc variant of a human IgG Fc polypeptide, wherein said Fc variant comprises the amino acid substitutions 308F/428L, wherein numbering is according to the EU index.
  3. A polypeptide comprising an Fc variant of a human IgG Fc polypeptide, wherein said Fc variant comprises the amino acid substitutions 259I/308F/428L, wherein numbering is according to the EU index.
  4. An anti-VEGF antibody having a variable heavy domain comprising SEQ ID NO:13 and a variable light domain comprising SEQ ID NO:14, wherein said anti-VEGF antibody comprises a variant Fc domain comprising the amino acid substitutions 428L/434S, wherein numbering is according to the EU index.
  5. An anti-CD25 antibody having a variable heavy domain comprising SEQ ID NO:17 and a variable light domain comprising SEQ ID NO:18, wherein said anti-CD25 antibody comprises a variant Fc domain comprising the amino acid substitutions 428L/434S, wherein numbering is according to the EU index.
  6. An anti-EGFR antibody having a variable heavy domain comprising SEQ ID NO:19 and a variable light domain comprising SEQ ID NO:20, wherein said anti-EGFR antibody comprises a variant Fc domain comprising the amino acid substitutions 428L/434S, wherein numbering is according to the EU index.
  7. An anti-TNF Fc fusion protein comprising SEQ ID NO:33.
  8. A polypeptide comprising an Fc variant of a human IgG Fc polypeptide, wherein said Fc variant comprises the amino acid substitutions 252Y/428L, wherein numbering is according to the EU index.
  9. A polypeptide comprising an Fc variant of a human IgG Fc polypeptide, wherein said Fc variant comprises the amino acid substitutions 307Q/434S, wherein numbering is according to the EU index.
  10. A polypeptide comprising an Fc variant of a human IgG Fc polypeptide, wherein said Fc variant comprises the amino acid substitutions 307Q/308F/434S, wherein numbering is according to the EU index.

Description

This application claims benefit under 35 U.S.C. §119(e) to USSN 61/016,793, filed December 26, 2007; USSN 61/ 031,353, filed February 25, 2008; USSN 61/046,353, filed April 18, 2008; USSN 61/050,172, filed May 2, 2008; USSN 61/079,779, filed July 10, 2008; and USSN 61/099,178, filed September 22, 2008. FIELD OF THE INVENTION The present application relates to optimized IgG immunoglobulin variants, engineering methods for their generation, and their application, particularly for therapeutic purposes. BACKGROUND OF THE INVENTION Antibodies are immunological proteins that each binds 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 chain variable domain and the light chain constant domain respectively. In IgG, a site on Fc between the Cγ2 and Cy3 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). Studies of rat and human Fc domains have demonstrated the importance of some Fc residues to the binding of FcRn. The rat and human sequences have about 64% sequence identity in the Fc regions (residues 237-443 in the numbering of EU index). See figures 3, 4, and 5 for the rat/human alignments of Fc, FcRn heavy chain, and FcRn light chain (beta-2-microglobulin). A model of the human Fc/FcRn complex has been built from the existing structure of the rat Fc/FcRn complex (Martin et al., 2001, Mol Cell 7:867-877, entirely incorporated by reference). The rat and human sequences share some residues that are critical for FcRn binding, such as H310 and H435 (Medesan et al., 1997 J. Immunol. 158(5):221-7; Shields et al., 2001, J. Biol. Chem. 276(9):6591-6604, both entirely incorporated by reference). In many positions, however, the human and rat proteins have different amino acids, giving t