What are the main side effects of Afamelanotide?

Afamelanotide side effects and warning signals include Nausea (most common), Implant site reaction, Skin darkening, Headache, and Fatigue.

What evidence level is Afamelanotide?

Afamelanotide is rated Level A; the listed research status is FDA Approved.

Skin & Beauty / Level A / FDA Approved / Last reviewed 2026-04-04

Afamelanotide Evidence Guide

Afamelanotide (Scenesse) is FDA-approved for the prevention of phototoxicity in adults with erythropoietic protoporphyria (EPP) - a rare, severely debilitating condition. The Phase 3 evidence in EPP is solid and the approval is well-founded. Outside EPP, evidence for vitiligo is emerging in Phase 2. This is a legitimate, approved therapeutic for its specific indication.

Our Take

Best for: Erythropoietic protoporphyria (EPP) phototoxicity prevention, vitiligo (investigational), melanocortin research
Evidence grade: Level A
Confidence: High
Starting point: 16mg implant subcutaneous every 2 months (EPP indication)

Benefits and Evidence

EPP Phototoxicity Reduction: Level A, includes human evidence - Langendonk et al. (2015, N Engl J Med, PASS study, n=94) showed afamelanotide 16 mg SC implant increased median pain-free sun exposure from 10 min to 70 min in EPP patients (p<0.001). FDA approved Scenesse in 2019 based on this and the CUV039 Phase III trial confirming reduced phototoxicity severity.
Skin Pigmentation: Level A, includes human evidence - Consistent increases in melanin density and visible skin darkening documented across multiple controlled trials. Effect persists for weeks after implant insertion.
Photoprotection: Level B, includes human evidence - Studies in healthy volunteers and photosensitive patients show increased minimal erythema dose (MED) and reduced sunburn response following treatment.

Side Effects and Warnings

Nausea (most common)
Implant site reaction
Skin darkening
Headache
Fatigue
Darkening of pre-existing nevi
Regular skin and mole examinations recommended during treatment
Not studied in patients with active melanoma or high melanoma risk

Research Dosage References

<strong>Subcutaneous implant</strong> - 16 mg - Every 2 months (up to 3 implants per year for EPP) - FDA-approved dosing for EPP. Implant is inserted above the iliac crest. Slow release over approximately 10 days.

Mechanism of Action

Afamelanotide selectively activates the melanocortin 1 receptor (MC1R): 1. Eumelanin synthesis: MC1R activation in melanocytes upregulates tyrosinase and related enzymes, shifting pigment production toward photoprotective eumelanin rather than phototoxic pheomelanin. 2. DNA repair enhancement: MC1R signaling promotes nucleotide excision repair of UV-induced DNA damage independent of pigmentation. 3. Anti-inflammatory activity: Reduces UV-induced inflammation and suppresses pro-inflammatory cytokines in the skin. 4. Photoprotection in EPP: Increased eumelanin provides a photoprotective barrier that reduces phototoxic reactions triggered by protoporphyrin IX accumulation.

Legal Status

FDA-approved (Scenesse) for erythropoietic protoporphyria (EPP) in adults. Also approved by EMA. Available only through restricted distribution programs (REMS). Prescription only.

Primary Sources

Afamelanotide for erythropoietic protoporphyria. New England Journal of Medicine, 2015.
Phase III trial of afamelanotide for prevention of phototoxicity in erythropoietic protoporphyria. British Journal of Dermatology, 2015.
Long-term safety of afamelanotide in patients with erythropoietic protoporphyria. British Journal of Dermatology, 2022.