Methods of modifying antibodies for purification of bispecific antibodies

A multispecific antibody comprising a first polypeptide and a second polypeptide,

• wherein the first polypeptide comprises a first heavy chain variable region and the second polypeptide comprises a second heavy chain variable region;
• wherein at least one position selected from positions 10, 12, 23, 39, 43, and 105 (Kabat numbering) in the first heavy chain variable region is occupied by a charged amino acid residue;
• and
• wherein the isoelectric point of the first polypeptide is different from the isoelectric point of the second polypeptide.

A multispecific antibody comprising a first polypeptide and a second polypeptide,

• wherein the first polypeptide comprises a first heavy chain constant region and the second polypeptide comprises a second heavy chain constant region;
• wherein at least one position selected from positions 137, 196, 203, 214, 217, 233, 268, 274, 276, 297, 355, 392, 419, and 435 (EU numbering) in the first heavy chain constant region is occupied by a charged amino acid residue;
• and
• wherein the isoelectric point of the first polypeptide is different from the isoelectric point of the second polypeptide.

A multispecific antibody comprising:

• a first polypeptide that comprises a first heavy chain variable region comprising the amino acid sequence of any one of SEQ ID NOs:
• 7-13;
• and
• a second polypeptide that comprises a second heavy chain variable region comprising the amino acid sequence of any one of SEQ ID NOs:
• 14-16.