Comparison
Afamelanotide vs. Sincalide
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
25126-32-3
Molecular weight
1646.87 g/mol
1143.29 g/mol
Half-life
12 h
no data
Sequence
Ac-Ser-Tyr-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2Asp-Tyr(SO3H)-Met-Gly-Trp-Met-Asp-Phe-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.
Sincalide
Sincalide activates CCK receptors, triggering gallbladder contraction and pancreatic enzyme secretion. This effect is used diagnostically to measure the gallbladder ejection fraction (e.g. in HIDA scintigraphy).
Evidence base
Highest evidence
Human RCT
Human trial
Studies
4
0
of which in humans
4
0
Effects recorded
4
1
Open conflicts
1
0
Documented adverse events
4
1
Legal status
Full entries
Frequently asked questions
- What is the difference between Afamelanotide and Sincalide?
- Afamelanotide is classified as "Research other", while Sincalide 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. Sincalide: Sincalide is the synthetic C-terminal octapeptide of the hormone cholecystokinin (CCK-8). As Kinevac it is FDA-approved to stimulate gallbladder contraction for diagnostic imaging. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Afamelanotide or Sincalide?
- The highest available evidence level is "Human RCT" for Afamelanotide and "Human trial" for Sincalide. 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 Sincalide in Germany and the United States?
- Germany: Afamelanotide — Prescription, Sincalide — Unclear. United States: Afamelanotide — Prescription, Sincalide — Prescription. These are factual summaries with source and review date on the individual pages.