Comparison
Afamelanotide vs. Degarelix
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
214766-78-6
Molecular weight
1646.87 g/mol
1632.3 g/mol
Half-life
12 h
1320 h
Sequence
Ac-Ser-Tyr-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2Ac-D-2Nal-D-4Cpa-D-3Pal-Ser-4Aph(Hor)-D-4Aph(Cbm)-Leu-Ilys-Pro-D-Ala-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.
Degarelix
Degarelix is a competitive GnRH receptor antagonist. It binds reversibly and immediately to the pituitary GnRH receptors and blocks their activation. This rapidly suppresses the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), which in turn lowers testosterone production in the testes. Unlike GnRH agonists (e.g., leuprorelin), which first cause a transient stimulation with a testosterone surge (flare), this direct antagonism lacks the initial stimulation phase, so testosterone declines without a preceding rise. This mechanism underlies the literature-described use in hormone-dependent prostate cancer.
Evidence base
Highest evidence
Human RCT
Human RCT
Studies
4
4
of which in humans
4
4
Effects recorded
4
4
Open conflicts
1
1
Documented adverse events
4
2
Legal status
Full entries
Frequently asked questions
- What is the difference between Afamelanotide and Degarelix?
- Afamelanotide is classified as "Research other", while Degarelix 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. Degarelix: Degarelix (trade name Firmagon) is a synthetic decapeptide and a gonadotropin-releasing hormone (GnRH) receptor antagonist. Unlike GnRH agonists, it blocks the receptor directly and does not trigger an initial testosterone surge (flare). It is an approved prescription medicine for the treatment of advanced, hormone-dependent prostate cancer. This page neutrally summarizes the evidence base and legal status and is not a usage or dosing recommendation. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Afamelanotide or Degarelix?
- The highest available evidence level is "Human RCT" for Afamelanotide and "Human RCT" for Degarelix. 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 Degarelix in Germany and the United States?
- Germany: Afamelanotide — Prescription, Degarelix — Prescription. United States: Afamelanotide — Prescription, Degarelix — Prescription. These are factual summaries with source and review date on the individual pages.