This disclosure provides a bispecific ligand directed toxin (BLT) that includes a diphtheria toxin (DT) molecule that has been mutated to create a DT molecule that induces less of an immune response than native diphtheria toxin. The deimmunized DT molecule is fused with targeting ligands to create a fusion protein that can selectively deliver the deimmunized DT to target cells to kill the target cells.