Melanotan-1 Research for Erythropoietic Protoporphyria (EPP)

Erythropoietic protoporphyria (EPP) is an autosomal recessive disorder caused by deficiency of ferrochelatase (FECH), the enzyme that catalyzes insertion of iron into protoporphyrin IX (PPIX). PPIX accumulates in red blood cells and is transported to skin, where sunlight exposure excites PPIX molecules and triggers immediate, excruciating burning pain without blistering. Patients are severely restricted in sunlight exposure, significantly impairing quality of life. Afamelanotide was evaluated in two pivotal randomized placebo-controlled trials. The US trial (CUV039, N=93) demonstrated 69.4 median pain-free hours over 180 days versus 40.8 hours for placebo (P=0.04). The European trial (N=74) showed 6.0 versus 0.8 median pain-free hours over 270 days (P=0.005), with phototoxic reactions reduced from 146 to 77 events (P=0.04). Both trials used a 16 mg subcutaneous implant administered every 60 days. Based on these trials, the EMA approved afamelanotide in December 2014 and the FDA approved it in October 2019 (NDA 210797), under the brand name Scenesse. This marked the first FDA-approved treatment for EPP. A 2025 German real-world cohort (N not specified) confirmed 91% treatment continuation with significant quality of life improvement (P<0.0001).