Thymosin α1 in melanoma: from the clinical trial setting to the daily practice and beyond

Thymosin alpha 1 (T alpha 1) is an immunomodulatory peptide released by the thymus gland in mammals. It was first described in 1977 as a potential agent for the treatment of immune deficiencies and cancer. Among solid tumors, a number of clinical trials have investigated the activity of T alpha 1 in melanoma. In particular, a large randomized phase II trial that evaluated the safety and efficacy of combining T alpha 1 with dacarbazine and interferon alpha in metastatic melanoma patients provided the rationale for further clinical applications. The main findings emerging from clinical trials and that support the therapeutic use of T alpha 1 in human melanoma are summarized and discussed.