Eumelanin and the photoprotection of skin color: linking experimental studies and clinical outcomes

Summary

This early clinical study evaluated the melanogenic effects of Melanotan II (MT-II), a cyclic analog of alpha-melanocyte-stimulating hormone, administered subcutaneously to human volunteers. MT-II produced significant darkening of the skin through increased eumelanin synthesis without requiring UV exposure, demonstrating the first clinical proof-of-concept for pharmacologically induced tanning.

Key Findings

• Subcutaneous Melanotan II (0.025 mg/kg) administered over 5 days produced measurable skin darkening as quantified by reflectance spectrophotometry
• Melanin content analysis confirmed the pigmentation was predominantly eumelanin (photoprotective brown-black pigment) rather than pheomelanin
• Nausea and facial flushing were the most common side effects, occurring transiently after injection and resolving within hours