Patent ID: 9718893
Date: 2017-08-01
CPC Classifications: A61P,C07K

Claim:
1. A recombinant bispecific antibody molecule consisting of a Fab fragment comprising a first binding site for a first antigen, a single chain Fv fragment comprising a second binding site for a second antigen and an immunoglobulin IgG1 CH2 domain, wherein the Fab fragment and the single chain Fv fragment are linked via the CH2 domain, wherein at least three amino acid residues of the CH2 domain that are able to mediate binding to Fe receptors are deleted or mutated by substitution with a different amino acid, thereby attenuating the binding of the CH2 domain to Fc receptors, wherein the at least three amino acid residues of the CH2 domain consist of sequence position 233 and at least two amino acids selected from the group consisting of sequence position 228, 230, 231, 232, 234, 235, 236, 237, 238, 265, 297, 327, and 330 (numbering of sequence positions according to the EU-index), and wherein further the amino acid residues of sequence positions 226 and 229 are deleted or mutated by substitution with a different amino acid, wherein either the first binding site or the second binding site binds a tumor associated antigen, and wherein the other of the first binding site or the second binding site binds a T cell or NK (natural killer) cell specific receptor molecule.