| abstract |
The present invention relates to immunoglobulin Fc variants having an increased binding affinity for FcRn, which is characterized by including one or more amino acid modifications selected from the group consisting of 307S, 308F, 380S, 380A, 428L, 429K, 430S, 433K and 434S (this numbering is according to the EU index) in the constant region of a native immunoglobulin Fc fragment. Owing to the high binding affinity for FcRn, the immunoglobulin Fc variants according to the present invention show more prolonged in vivo half-life, and thus can be used for the preparation of a long-acting formulation of protein drugs. |