Melanotan I (Scenesse): MC1R Photoprotection for EPP

MT-I (afamelanotide, brand Scenesse) is selective for the melanocortin-1 receptor (MC1R) on melanocytes — it drives skin pigmentation for photoprotection without the libido, erection priming, or pronounced nausea seen with MT-II. MT-II is a non-selective α-MSH analog hitting MC1R, MC3R, MC4R, and MC5R. MT-I is FDA-approved (2019) as Scenesse for erythropoietic protoporphyria; MT-II has never been approved by FDA or EMA and is sold gray-market.

No. Scenesse is approved only for adults with erythropoietic protoporphyria to reduce phototoxic skin reactions. Clinuvel, the FDA, and EMA have all explicitly declined cosmetic-tanning use. The drug increases freckle and nevus formation, which is why an annual dermatology exam is part of the on-label protocol — unsanctioned use bypasses that monitoring entirely.

As a 16 mg bioresorbable implant (~1.5 cm rod, 1.5 mm diameter) placed subcutaneously above the iliac crest by a Clinuvel-trained clinician under local anaesthesia. The implant dissolves over ~8 weeks, releasing afamelanotide steadily. Standard schedule is every 60 days, with 4-6 implants per year aligned with the patient's high-light season (typically March-October in temperate latitudes).

EPP patients accumulate protoporphyrin IX in red blood cells from a partial ferrochelatase deficiency. When skin is exposed to visible light (especially 380-600 nm) or UV-A, that protoporphyrin gets excited and generates reactive oxygen species — producing severe burning pain within minutes. Afamelanotide activates MC1R, shifting melanocytes toward eumelanin (dark pigment) production. Eumelanin absorbs the offending wavelengths before they can excite protoporphyrin, increasing pain-free outdoor time.

No. PT-141 is a 7-amino-acid fragment derived from MT-II that acts primarily on MC4R and MC3R in the central nervous system — it is FDA-approved as Vyleesi for hypoactive sexual desire disorder in premenopausal women. MT-I/afamelanotide is a 13-amino-acid full-length α-MSH analog selective for MC1R in the skin. They share the parent α-MSH backbone but target different receptors, treat different conditions, and produce very different clinical effects.

Scenesse is manufactured and distributed exclusively by Clinuvel Pharmaceuticals (ASX: CUV). In the US, access is through certified specialty centers — Clinuvel trains and credentials individual clinicians to insert the implant. EPP diagnosis requires confirmed elevated free erythrocyte protoporphyrin IX plus genetic testing (typically biallelic ferrochelatase mutations). Insurance coverage in the US is conditional on documented EPP and Clinuvel-sponsored patient access support handles benefits navigation.