| 摘要 |
PURPOSE: An immunoglobulin Fc fragment derivative is provided to have extended in vivo half life by high binding affinity to neonatal Fc receptor (FcRn) and to manufacture a sustained formulation of a protein drug. CONSTITUTION: An immunoglobulin Fc fragment derivative has the modification of amino acid residues selected from a group consisting of 308F, 380S, 380A, 428L, 429K, 430S, 433K, and 434S (the numbering is based on EU index) in the constant region of a wild type immunoglobulin Fc fragment. The immunoglobulin Fc fragment derivative has enhanced binding affinity to FcRn. The modification of the amino acid residue is selected from a group consisting of 428L/434S, 433K/434S, 429K/433K, 428L/433K, 308F/380A, 307S/380S, and 380S/434S. A method for enhancing in vivo half life of a physiologically active polypeptide comprises the step of binding the immunoglobulin Fc fragment derivative with the physiologically active polypeptide through covalent bond by a non-peptidyl polymer. |
