MOLECULE HAVING EXTENDED HALF-LIFE, AND COMPOSITION AND USE THEREOF

摘要

PROBLEM TO BE SOLVED: To provide molecules including IgG, non-IgG immunoglobulin, protein and non-protein substance, having extended in vivo half-life due to the presence of an IgG constant domain or its FcRn binding portion, having one or more amino acid modification which increases affinity of the IgG constant domain or its FcRn binding fragment to FcRn.SOLUTION: There is provided a modified IgG having increased half-life compared to the half-life of a corresponding IgG comprising wild-type human IgG CH3 domain, substitution in the amino acid residue 433 being substitution by lysine, substitution in the amino acid residue 434 being substitution by phenylalanine, and substitution in the amino acid residue 436 being substitution by histidine.