Chugai Seiyaku Kabushiki Kaisha

Futa Mimoto

Tomoyuki Igawa

Taichi Kuramochi

Hitoshi Katada

Shojiro Kadono

Atsuhiko Maeda

Hirotake Shiraiwa

Meiri Kawazoe

Tatsuhiko Tachibana

Yuki Iwayanagi

Kenta Haraya

Naoka Hironiwa

Atsushi Matsuo

Eriko Murata

The present inventors produced a heterodimerized polypeptide having an Fc region formed from two polypeptides with different amino acid sequences (a first polypeptide and a second polypeptide), and succeeded in producing a heterodimerized polypeptide containing an Fc region with improved Fc region function compared to that of a homodimer in which the Fc region is composed of only the first polypeptide or only the second polypeptide by conventional technology.

Heterodimerized polypeptide

Polypeptides with improved stability as compared to that of a parent polypeptide were successfully obtained by modifying at least one amino acid in a loop region of the antibody Fc region. Furthermore, by combining multiple amino acid modifications in the loop region, polypeptides with maintained or enhanced FcγR-binding activity as well as improved thermal stability, polypeptides with decreased FcγR-binding activity as well as improved thermal stability, and polypeptides with not only improved thermal stability and adjusted FcγR-binding activity but also decreased aggregate content, as compared to those of a parent polypeptide, were successfully obtained.

Modified Fc region of antibody

The present invention demonstrated that the modification of the Fc region of an antigen-binding molecule into an Fc region that does not form in a neutral pH range a heterotetramer complex containing two molecules of FcRn and an active Fc&#x3b3; receptor improved the pharmacokinetics of the antigen-binding molecule and reduced the immune response to the antigen-binding molecule. The present invention also revealed methods for producing antigen-binding molecules having the properties described above, and successfully demonstrated that pharmaceutical compositions containing as an active ingredient such an antigen-binding molecule or an antigen-binding molecule produced by a production method of the present invention have excellent features over conventional antigen-binding molecules in that when administered, they exhibit improved pharmacokinetics and reduced in vivo immune response.

Method for altering plasma retention and immunogenicity of antigen-binding molecule

A polypeptide containing an antibody Fc region variant which has an amino acid sequence in which an amino acid alteration at position 238 according to EU numbering is combined with other specific amino acid alteration(s), was found to have decreased binding activities to all activating Fc&#x3b3;Rs, in particular Fc&#x3b3;RIIa (R type), while maintaining its Fc&#x3b3;RIIb-binding activity, when compared to a polypeptide containing a native IgG Fc region.

Fc region variant

The present inventors have successfully found a large number of Fc variants with remarkably increased binding activity against and/or binding selectivity for mouse Fc&#x3b3;RII by introducing amino acid alteration(s) to the Fc region.

Mouse Fc&#x3b3;ammaRII-specific Fc antibody

The present inventors have successfully prepared an antibody Fc region dimer that has binding activity against each of an antigen and Fc&#x3b3;R, but does not bind to the antigen and the Fc&#x3b3;R at the same time, and a polypeptide comprising the Fc region dimer. The present invention enables the preparation of a multispecific binding polypeptide capable of avoiding an adverse reaction that may be caused by its binding to an antigen and Fc&#x3b3;R at the same time. Thus, the present invention provides a polypeptide suitable as a drug.

Antigen-binding molecule containing modified Fc region

It is intended to provide a method for efficiently and stably producing a heteromultimer by incubating, under a reducing condition, homo variants of plural types of polypeptides in which the alteration of amino acids that form the interface between Fc regions and/or the alteration to destabilize the stability of a heavy chain CH3 region has been introduced in the heavy chain CH3 regions so at to achieve the promotion of the dissociation of the Fc regions and/or the control of the association thereof through the use of charge repulsion.

Method for producing polypeptide heteromultimer

An objective of the present invention is to provide an Fc region variant with enhanced Fc&#x3b3;RIIb-binding activity, and/or enhanced binding selectivity to Fc&#x3b3;RIIb compared to Fc&#x3b3;RIIa (type R), as compared to those of a polypeptide containing an Fe region to which an amino acid alteration(s) has not been introduced; a polypeptide which includes the Fc region variant; a pharmaceutical composition containing the polypeptide; preventing therapeutic or preventive agent for immunological inflammatory diseases that includes the pharmaceutical composition; a production method thereof; and a method of enhancing Fc&#x3b3;RIIb-binding activity and also enhancing binding selectivity to Fc&#x3b3;RIIb compared to Fc&#x3b3;RIIa (type R). It was found that a polypeptide containing an antibody Fc region variant that contains an amino acid sequence in which an amino-acid alteration at position 238 (EU numbering) is combined with other specific amino-acid alterations enhances Fc&#x3b3;RIIb-binding activity, and/or enhances binding selectivity to Fc&#x3b3;RIIb compared to Fc&#x3b3;RIIa (type R).

FcgammaRIIB-specific Fc region variant

The present inventors produced a heterodimerized polypeptide having an Fc region formed from two polypeptides with different amino acid sequences (a first polypeptide and a second polypeptide), and succeeded in producing a heterodimerized polypeptide containing an Fc region with improved function compared to that of a homodimer in which the Fc region is composed of only the first polypeptide or the second polypeptide by conventional technology.

The present inventors carried out dedicated research to generate antibody constant regions with reduced Fc&#x3b3; receptor-binding activity by altering amino acid sequences in the antibody constant region. As a result, the present inventors successfully identified novel constant region sequences with reduced Fc&#x3b3; receptor-binding activity compared to conventional antibody constant regions.

Antibody constant region variants with reduced Fcgammar binding

The present invention provides: a modified FcRn-binding domain having an enhanced affinity for the Fc Receptor neonatal (FcRn) at neutral pH; an antigen-binding molecule comprising said FcRn-binding domain, which has low immunogenicity, high stability and form only a few aggregates; a modified antigen-binding molecule having an increased FcRn-binding activity at neutral or acidic pH without an increased binding activity at neutral pH for a pre-existing anti-drug antibody; use of the antigen-binding molecules for improving antigen-binding molecule-mediated antigen uptake into cells; use of the antigen-binding molecules for reducing the plasma concentration of a specific antigen; use of the modified FcRn-binding domain for increasing the total number of antigens to which a single antigen-binding molecule can bind before its degradation; use of the modified FcRn-binding domain for improving pharmacokinetics of an antigen-binding molecule; methods for decreasing the binding activity for a pre-existing anti-drug antibody; and methods for producing said antigen-binding molecules.

Growing community of inventors

Shizuoka, Japan

Futa Mimoto