Albumin variants

A conjugate comprising:

• a polypeptide comprising an albumin having an amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO:
• 2 and having a substitution in Domain I of said albumin and having a substitution in Domain III of said albumin relative to the amino acid sequence set forth in SEQ ID NO:
• 2, wherein said albumin has an increased binding affinity to FcRn relative to the binding affinity of an albumin comprising the amino acid sequence of SEQ ID NO:
• 2 to FcRn, and wherein said substitution in Domain I is selected from amino acids corresponding to positions 82, 83, 111, 112, or any combination thereof of the amino acid sequence of SEQ ID NO:
• 2 and said substitution in Domain III is selected from amino acids corresponding to positions 425, 505, 510, 512, 524, 527, 531, 534, 569, 573, 575, or any combination thereof of the amino acid sequence of SEQ ID NO:
• 2;
• and
• a conjugation partner.

A method of producing a conjugate comprising:

• providing an albumin having an amino acid sequence that is at least 90% identical to the amino acid sequence of SEQ ID NO:
• 2 and having a substitution in Domain I of said albumin and having a substitution in Domain III of said albumin relative to the amino acid sequence set forth in SEQ ID NO:
• 2, wherein said albumin has an increased binding affinity to FcRn relative to the binding affinity of an albumin comprising the amino acid sequence of SEQ ID NO:
• 2 to FcRn, and wherein said substitution in Domain I is selected from amino acids corresponding to positions 82, 83, 111, 112, or any combination thereof of the amino acid sequence of SEQ ID NO:
• 2 and said substitution in Domain III is selected from amino acids corresponding to positions 425, 505, 510, 512, 524, 527, 531, 534, 569, 573, 575, or any combination thereof of the amino acid sequence of SEQ ID NO:
• 2;
• and
• conjugating the albumin to a conjugation partner selected from a therapeutic, prophylactic, diagnostic, imaging or other moiety.