Disomotide is an oligopeptide in phase III clinical development for the treatment of melanoma. Vaccination with the disomotide peptide has resulted in very high levels of circulating T cells that were capable of recognizing and killing melanoma cancer cells in vitro. In a single-group, phase 2 study, patients with metastatic melanoma were immunized with the disomotide peptide vaccine in Montanide ISA-51 (incomplete Freund’s adjuvant), followed by high-dose interleukin-2, leading to objective clinical responses in 13 of 31 patients. Randomized study showed the clinical benefit of a vaccine in the treatment of patients with measurable metastatic melanoma. Patients receiving the disomotide with interleukin-2 were more than twice as likely to have a clinical response as those receiving interleukin-2 alone.