FDA-Approved Forms
- Scenesse (subcutaneous implant, 16 mg): increasing pain-free light exposure in adults with erythropoietic protoporphyria (EPP), approved 2019
What it is
Melanotan I (MT-1) is a synthetic tridecapeptide analog of alpha-melanocyte-stimulating hormone (alpha-MSH), also known by its chemical shorthand [Nle4-D-Phe7]-alpha-MSH or NDP-MSH. Unlike the cyclic Melanotan II, MT-1 keeps the linear backbone of natural alpha-MSH with two modifications that make it far more resistant to breakdown in the body.[3]
MT-1 is the same molecule as afamelanotide, the active ingredient in Scenesse, an FDA-approved subcutaneous implant for erythropoietic protoporphyria. Research-grade MT-1 sold by peptide vendors is chemically identical to the drug substance, though it is not sold, dosed, or regulated as the approved product.
What researchers study it for
- Skin pigmentation MT-1 activates MC1R receptors on melanocytes to stimulate eumelanin production. An early human study found that two weeks of subcutaneous dosing increased eumelanin content in forehead skin samples, which is where the compound picked up the name Melanotan-I.[1]
- Photoprotection and UV damage reduction A randomized controlled trial in 65 fair-skinned volunteers found that MT-1 dosing increased melanin density and reduced UV-induced sunburn cells and DNA damage markers, with the largest gains in people who started with the lowest melanin levels.[2]
- Photosensitivity conditions Because induced pigmentation can blunt UV sensitivity, researchers have studied MT-1 and its identical molecule afamelanotide in conditions where sunlight exposure causes symptoms, including solar urticaria and erythropoietic protoporphyria, the indication behind its eventual FDA approval as Scenesse.[4]
- Anti-inflammatory and skin conditions beyond pigmentation Melanocortin receptors also sit on immune and skin cells outside the pigment pathway, and researchers have studied MT-1's anti-inflammatory activity in conditions such as acne vulgaris and Hailey-Hailey disease, separate from its tanning effect.[6]
- Safety and immunogenicity in long-term use Because afamelanotide is dosed repeatedly over years in EPP patients, researchers have specifically studied whether long-term exposure triggers antibody formation against the peptide itself or against the body's own natural alpha-MSH.[5]
Research context
MT-1 has one of the more complete clinical research records among gray-market peptides, largely because it is the same molecule behind an approved drug. Early toxicology work in animals in the late 1980s established a basic safety profile before human dosing began.[3] Human studies through the 1990s and 2000s, including a randomized controlled trial, confirmed that subcutaneous dosing reliably increases skin melanin and reduces measurable UV damage, with the strongest effect in people who tan poorly on their own.[1][2]
That research arc led to afamelanotide's development and its 2019 FDA approval as Scenesse for erythropoietic protoporphyria, a rare condition in which sunlight exposure causes severe pain. Long-term safety data from that patient population, including antibody monitoring, comes from people using the approved implant under medical supervision rather than from the self-administered research-grade product, so the depth of the drug-approval evidence doesn't fully carry over to how vendors' vials are typically used.[5]
Typical research parameters
| Parameter | Typical range |
|---|---|
| Common vial sizes | 10 mg, also 5 mg |
| Supplied as | Lyophilized powder, reconstituted with bacteriostatic water before use |
| Storage | Refrigerated after reconstitution; lyophilized powder stable at room temperature |
| Stability | Lyophilized: 24+ months / Reconstituted: 4–6 weeks refrigerated |
| Administration studied | Subcutaneous injection in human research; the approved drug form is a subcutaneous implant |
| Purity to look for | ≥98% by HPLC; third-party certificate of analysis recommended |
References
- [1] Dorr RT, Dvorakova K, Brooks C, Lines R, Levine N, Schram K, Miketova P, Hruby V, Alberts DS. Increased eumelanin expression and tanning is induced by a superpotent melanotropin [Nle4-D-Phe7]-alpha-MSH in humans. Photochemistry and Photobiology. 2000;72(4):526-32. PubMed ↗
- [2] Barnetson RS, Ooi TK, Zhuang L, Halliday GM, Reid CM, Walker PC, Humphrey SM, Kleinig MJ. [Nle4-D-Phe7]-alpha-melanocyte-stimulating hormone significantly increased pigmentation and decreased UV damage in fair-skinned Caucasian volunteers. The Journal of Investigative Dermatology. 2006;126(8):1869-78. PubMed ↗
- [3] Dorr RT, Dawson BV, al-Obeidi F, Hadley ME, Levine N, Hruby VJ. Toxicologic studies of a superpotent alpha-melanotropin, [Nle4, D-Phe7]alpha-MSH. Investigational New Drugs. 1988;6(4):251-8. PubMed ↗
- [4] Haylett AK, Nie Z, Brownrigg M, Taylor R, Rhodes LE. Systemic photoprotection in solar urticaria with alpha-melanocyte-stimulating hormone analogue [Nle4-D-Phe7]-alpha-MSH. British Journal of Dermatology. 2011;164(2):407-14. PubMed ↗
- [5] Lengweiler S, Kreim S, Barman-Aksözen J, Maurer M, Minder EI. Evaluation of the immunogenicity of the synthetic alpha-melanocyte-stimulating hormone (alpha-MSH) analogue afamelanotide ([Nle4-D-Phe7]-alpha-MSH, Scenesse) in erythropoietic protoporphyria patients by ELISA detecting both anti-afamelanotide and anti-alpha-MSH antibodies. Skin Pharmacology and Physiology. 2015;28(2):103-13. PubMed ↗
- [6] Böhm M, Ehrchen J, Luger TA. Beneficial effects of the melanocortin analogue Nle4-D-Phe7-alpha-MSH in acne vulgaris. Journal of the European Academy of Dermatology and Venereology. 2014;28(1):108-11. PubMed ↗