Optimizing denileukin diftitox (Ontak®) therapy

Denileukin diftitox (Ontak®) is a genetically engineered recombinant fusion protein composed of the full length interleukin 2 and the catalytic domain of diphtheria toxin. As such, Ontak or formerly DAB389IL2 is the first targeted therapy of the fusion toxin class to be approved. This therapy has broad applicability for targeting any ligand receptor that internalizes after binding. Ontak was first introduced in 1992, and tested for safety and activity in autoimmune disease (rheumatoid arthritis, psoriasis), type I diabetes, HIV, and hematologic malignancies (Strom TB 1993).