Melanotan II (Melanotan 2) Clinical Research Status

Introduction:

Melanotan II (Melanotan 2, MT-II) is a synthetic analog of α-MSH that has been studied since the 1980s for skin pigmentation, sexual function, and metabolic regulation.¹ While popularized as a “tanning peptide,” Melanotan II has never received FDA or EMA approval, and remains a research-use-only compound. This article reviews the current state of research and trials.

History of Clinical Research

1980s origins: Developed at the University of Arizona as a potential sunless tanning agent.¹
Early studies: Focused on pigmentation disorders (vitiligo, erythropoietic protoporphyria).²
Expanded research: Explored in erectile dysfunction and female sexual arousal disorder, due to MC4R receptor activity.³
Metabolic focus: Animal and small human studies investigated appetite suppression and weight regulation.⁴

Current Clinical Status

Pigmentation: No large-scale or FDA-cleared trials; research remains limited to early-phase studies.²
Sexual function: Phase II clinical trials showed increased erectile response and sexual desire, but side effects limited development.³
Metabolic disorders: Preclinical and primate studies suggest appetite and weight regulation effects, but no approved therapies.⁴
Regulatory position: Melanotan II is not approved for any indication, and official agencies have issued warnings against cosmetic/tanning use.⁵

Research Limitations

Short duration: Most human trials lasted only weeks.
Small sample sizes: Typically fewer than 100 participants.
Unregulated markets: Current availability is through research supply channels, not clinical development.
Safety concerns: Mole darkening and potential melanoma risk require more study.³⁵

Summary

Melanotan II has been studied for:

Pigmentation disorders (vitiligo, photosensitivity)
Sexual function (erectile dysfunction, female arousal disorder)
Metabolic research (appetite suppression, obesity models)

Despite decades of interest, it remains unapproved, with clinical progress stalled due to side effects and safety concerns. Future research may clarify its risk–benefit profile, but for now, Melanotan II is restricted to research use only.

FAQs About Melanotan II Research

Has Melanotan II been tested in humans?

Yes, in small Phase I and II studies for pigmentation and sexual function.

Why isn’t Melanotan II approved?

Concerns about side effects, mole darkening, and insufficient long-term safety data.

Is Melanotan II still being researched?

Limited academic research continues, but there are no major ongoing FDA or EMA trials.

What was the most promising area of research?

Sexual function showed the strongest clinical results, but side effects limited approval.

References

Hadley ME, et al. “Discovery and development of melanocortin peptides for tanning and skin protection.” Ann N Y Acad Sci. 1999;885:342–356. https://pubmed.ncbi.nlm.nih.gov/10816663/
Böhm M, et al. “Melanocortin receptor ligands: new horizons for skin biology and clinical dermatology.” J Invest Dermatol. 2006;126(9):1966–1975. https://pubmed.ncbi.nlm.nih.gov/16912692/
Wessells H, et al. “Effect of melanocortin receptor agonist Melanotan-II in men with erectile dysfunction: a randomized controlled trial.” Arch Neurol. 2000;57(4):449–455. https://pubmed.ncbi.nlm.nih.gov/10768691/
Kievit P, et al. “Chronic treatment with a melanocortin-4 receptor agonist causes weight loss and improves insulin sensitivity in diet-induced obese monkeys.” J Clin Endocrinol Metab. 2013;98(2):E291–E300. https://pubmed.ncbi.nlm.nih.gov/23275596/
US FDA. “Melanotan II not approved for tanning or cosmetic use.” FDA Safety Bulletin. https://www.fda.gov/consumers/consumer-updates/tanning-pills-and-injections