| abstract |
A variant of a parent polypeptide comprising an Fc region, a variant which exhibits greater binding to FcRn in comparison to said parent polypeptide, and comprises at least two amino acid modifications, the aforementioned comprising at least two amino acid modifications: (i) a amino acid modification that is 434Y, and (ii) at least one amino acid modification that is 315D, or 378V, of the Fc region, in which the numbering of the amino acids in the Fc region is that of the EU index as in Kabat. |