Patent ID: 11965030
Assignee: SANOFI
Field: Biotechnology (Chemistry)
Classification: CPC A  C | IPC C

Claim 6:
7. An antigen-binding protein comprising:
an antigen-binding domain; and
a constant heavy chain CH1 region paired with a constant light chain CL region,
wherein the antigen-binding domain selectively binds to a target antigen, and wherein:
the CH1 region comprises K221E and K228D mutations at Kabat positions 221 and 228 of the CH1 and the CL region comprises D122K and E123K mutations at Kabat positions 122 and 123,
wherein the antigen-binding protein further comprises at least one VH/VL pair comprising opposite charged mutations to facilitate pairing, said opposite charged mutations comprising (1) a mutated residue in the VH region at Kabat position 39 selected from E, D, K, R, or H, and (2) a mutated residue in the VL region at Kabat position 38 selected from E, D, K, R, or H, and wherein the mutated residue in the VH region has an opposite charge from the mutated residue in the VL region.