Comparison
Afamelanotide vs. Melanotan II
Two peptides side-by-side — identity, evidence base, legal status and known adverse events.
Identity
Category
Research other
Research other
CAS no.
75921-69-6
121062-08-6
Molecular weight
1646.87 g/mol
1024.18 g/mol
Half-life
12 h
1 h
Sequence
Ac-Ser-Tyr-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-NH2Mechanism of action
Afamelanotide
Afamelanotide is a synthetic analogue of α-melanocyte-stimulating hormone. It differs from native α-MSH by two substitutions — norleucine at position 4 and D-phenylalanine at position 7 — which make it metabolically more stable and more potent. As an agonist at the melanocortin-1 receptor (MC1R) on melanocytes, it activates adenylate cyclase, raises cAMP and increases tyrosinase activity via the transcription factor MITF. This shifts pigment synthesis toward eumelanin, which absorbs UV and visible light and has antioxidant properties — the presumed mechanism of photoprotection in EPP.
Melanotan II
Melanotan II binds non-selectively to all five melanocortin-receptor subtypes (MC1R-MC5R). Via MC1R in melanocytes, eumelanin synthesis is stimulated (pigmenting effect). Via MC4R and MC3R in the CNS, appetite, sexual function and blood pressure are modulated. The cyclic structure and D-amino acids increase stability compared to natural α-MSH.
Evidence base
Highest evidence
Human RCT
Human trial
Studies
4
9
of which in humans
4
5
Effects recorded
4
4
Open conflicts
1
1
Documented adverse events
4
6
Legal status
Full entries
Frequently asked questions
- What is the difference between Afamelanotide and Melanotan II?
- Afamelanotide is classified as "Research other", while Melanotan II is classified as "Research other". Afamelanotide: Afamelanotide (brand name Scenesse) is a synthetic 13-amino-acid analogue of α-melanocyte-stimulating hormone (α-MSH) and a melanocortin-1 receptor agonist. Unlike most peptides covered here, it is a regularly approved medicine: EMA approval in 2014/2015, FDA approval in 2019, in each case as a subcutaneous implant for the prevention of phototoxicity in adults with erythropoietic protoporphyria (EPP). It promotes eumelanin formation in the skin. Melanotan II: Cyclic hepta-peptide and non-selective melanocortin-receptor agonist. Originally researched at the University of Arizona as a sun-protection concept — never approved as a medicine. Widespread on the black market; regulatory warnings for cardiovascular and oncological risks. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Afamelanotide or Melanotan II?
- The highest available evidence level is "Human RCT" for Afamelanotide and "Human trial" for Melanotan II. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.
- What is the legal status of Afamelanotide and Melanotan II in Germany and the United States?
- Germany: Afamelanotide — Prescription, Melanotan II — Unapproved. United States: Afamelanotide — Prescription, Melanotan II — Unapproved. These are factual summaries with source and review date on the individual pages.