Comparison
Afamelanotide vs. Desmopressin
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
16679-58-6
Molecular weight
1646.87 g/mol
1069.2 g/mol
Half-life
12 h
3 h
Sequence
Ac-Ser-Tyr-Ser-Nle-Glu-His-D-Phe-Arg-Trp-Gly-Lys-Pro-Val-NH2Mpa-Tyr-Phe-Gln-Asn-Cys-Pro-D-Arg-Gly-NH2 (Disulfid 1-6)Mechanism 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.
Desmopressin
Desmopressin is a structurally modified analogue of the nine-residue peptide hormone vasopressin. Deamination at the N-terminus (1-deamino) and replacement of L-arginine by D-arginine at position 8 prolong the duration of action and render the compound largely selective for the vasopressin V2 receptor, while the V1-mediated vasoconstrictive effect is strongly reduced. Acting on V2 receptors in the renal collecting ducts, it promotes insertion of aquaporin-2 water channels into the apical membrane, increasing water reabsorption and reducing urine volume (antidiuretic effect). In addition, via V2 receptors on the vascular endothelium, desmopressin stimulates the release of von Willebrand factor and factor VIII from endothelial stores (Weibel-Palade bodies), improving primary haemostasis.
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 Desmopressin?
- Afamelanotide is classified as "Research other", while Desmopressin 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. Desmopressin: Desmopressin (DDAVP) is a synthetic analogue of the endogenous hormone vasopressin (antidiuretic hormone, ADH). Deamination of the first amino acid and substitution of L-arginine with D-arginine give it selective activity at the V2 receptor with strongly reduced pressor (V1) activity. It has been approved for decades for indications including central diabetes insipidus, primary nocturnal enuresis, and bleeding tendency in von Willebrand disease type 1 and mild haemophilia A. The principal safety concern is hyponatremia or water intoxication. This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, Afamelanotide or Desmopressin?
- The highest available evidence level is "Human RCT" for Afamelanotide and "Human RCT" for Desmopressin. 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 Desmopressin in Germany and the United States?
- Germany: Afamelanotide — Prescription, Desmopressin — Prescription. United States: Afamelanotide — Prescription, Desmopressin — Prescription. These are factual summaries with source and review date on the individual pages.