The application of afamelanotide, an α-melanocyte stimulating hormone agonistic 
analogue to protoporphyria, a disease with absolute sunlight-intolerance is 
discussed. The clinics, genetics and existing therapies of protoporphyria are 
described. The physiological receptor-mediated intracellular signaling of 
α-melanocyte stimulating hormone and effects of receptor variants are outlined. 
The pharmacological action of afamelanotide and the rationale behind its 
application in protoporphyria are given. The results of several Phase II and III 
and safety issues are discussed. The trial results were significant, although 
the effects were not very large in absolute terms, and the risk-safety profile 
is favorable today. Based on the high compliance rate and the excellent 
consistency in clinical effectiveness during six years of compassionate use 
program in Switzerland, we expect afamelanotide and analogues to become a 
prospective therapeutic tool. Moreover, we hope that dosage forms suitable for 
children will be developed in future, as children and adolescents suffer most in 
protoporphyria.