irreversible DNA damage and exerts it cytotoxicity through alkylation of DNA. Melflufen is currently undergoing Phase 2 efficacy studies in patients with relapsed and relapsed-refractory multiple myeloma. The peptidase targeting causes melflufen and its metabolites to accumulate in the diseased cells. This results in targeted delivery of the active moieties to the cancer cells, and thereby better treatment of the disease.