Description

Thymosin alpha-1 is an immunomodulatory polypeptide belonging to the group of thymic hormones. It is produced endogenously by the thymus gland and increases T cell-mediated immune responses by several mechanisms, including stimulation of T-cell differentiation and/or maturation, activation of natural killer cells and dendritic cells, and stimulation of proinflammatory cytokine release. Pilot studies in patients with advanced melanoma have suggested that thymosin alpha-1 may improve the efficacy of dacarbazine-based regimens. Thymosin alpha-1 has had a very favorable adverse reactions, profile in more than 2000 individuals treated to date.

The combination of thymosin alpha-1 + dacarbazine + interferon alpha has been studied in a multicenter randomized study in 488 patients with metastatic melanomas. There were several durable responses in patients who were given thymosin alpha-1; the median duration of response was 1.9–23 months, which was sufficient to reject the null-hypothesis that the expected response rate in the treatment groups would be the same. There was also a trend towards improved progression-free survival in patients given thymosin alpha-1. Based on these results, it was concluded that thymosin alpha-1 could potentiate the efficacy of dacarbazine. The addition of thymosin alpha-1 to dacarbazine and interferon-alfa did not lead to any additional adverse reactions.