We have deimmunized Diphtheria toxin (called "DIDT") through the approach of identifying and neutralizing its T cell epitopes. In the absence of T cell epitopes, the toxin will not be recognized as foreign and therefore will not elicit an immune response. We have accomplished this while retaining the toxin's full potency. Thus, we now have a platform technology that can be broadly applied to developing extremely potent drugs for a broad range of targets. Since fusion toxins are single polypeptides, they can be manufactured without the complication of chemical conjugation and do not require unusual precautions or a dedicated facility. For every indication where ADCs are being developed today, our deimmunized Diphtheria toxin (DIDT) platform offers an attractive alternative approach. Our technology is broadly protected by patents issued worldwide.