Patent ID: 9650445
Date: 2017-05-16
CPC Classifications: A61K,A61P,C07K

Claim:
1. A composition for redirecting T cells to unwanted cells comprising: (i) a targeting moiety capable targeting to unwanted cells wherein the targeting moiety is an anti-HER2 antibody or antigen binding fragment thereof and wherein the targeting moiety is not masked, and (ii) at least one further moiety that has a masked immune cell binding region so as to prevent binding of the further moiety to an immune cell, wherein the immune cell binding region is an anti-CD3 antibody or antigen binding fragment thereof, and wherein the masked immune cell binding region is capable of being selectively unmasked by cleavage of at least one protease cleavage site when the molecule is in the vicinity of the unwanted cells so as to allow binding of the further moiety to an immune cell and, wherein the further moiety is a scFv antibody in which the linker that joins the heavy chain variable domain (VH) and light chain variable domain (VL) is of insufficient length, optionally a peptide linker of 14 or less amino acids, to allow pairing of the VH and VL domains such that the scFv antibody cannot bind to the immune cell, and wherein, when in the vicinity of the unwanted cells, pairing of the VH and VL domains occurs by selectively cleaving one or more cleavage sites in said linker such that the VH and VL domains from the scFv antibody can bind to the immune cell.