Patent ID: 7981400

Claim:
A method for treating tumor or cancer cells expressing Gb 3 receptors, said method comprising administering to a mammal in need of such treatment a hybrid compound having the following formula: STxB-Z(n)-Cys-Y-T wherein STxB is the Shiga Toxin B subunit, Z(n) wherein n is 0 or 1 and when n is 1, Z is an amino acid residue devoid of a sulfhydryl group, or is a polypeptide, Cys is the amino acid residue for Cysteine T is a molecule selected from the group consisting of: i) cytotoxic agents, ii) prodrugs and iii) enzymes for the conversion of a prodrug to a drug, Y is an enzyme cleavable linker between T and Cys, said linker being cleavable for the release of T after the internalization of the hybrid compound into said cells.