– Dersimelagon, also known as MT-7117 and WHO 10832, is a novel, orally-administered, small molecule, selective melanocortin-1 receptor (MC1R) agonist that increases skin melanin without sun exposure and is being developed to increase light tolerance in EPP/XLP patients. Dersimelagon significantly boosted sunlight tolerance in patients with erythropoietic protoporphyria in a multicenter, phase 2, randomized trial.