This review says the brain’s melanocortin system is a hot target for drugs that could help with weight issues, muscle loss, and even mood, and it points out that a few peptide drugs (like setmelanotide for obesity and bremelanotide/pt‑141 for low sexual desire) have already been approved, proving the safety of this drug class. For DIY biohackers, it means the science is solid, but there’s no new dosing recipe yet—just a heads‑up that future compounds may become available for metabolic and performance tweaks.

A large body of preclinical and clinical data shows that the central melanocortin system is a promising therapeutic target for treating various metabolic disorders such as obesity and cachexia, as well as anorexia nervosa. Setmelanotide, which functions by engaging the central melanocortin circuitry, was approved by the FDA in 2020 for use in certain forms of syndromic obesity. Furthermore, the FDA approvals in 2019 of two peptide drugs targeting melanocortin receptors for the treatment of generalized hypoactive sexual desire disorder (bremelanotide) and erythropoietic protoporphyria-associated phototoxicity (afamelanotide) demonstrate the safety of this class of peptides. These approvals have also renewed excitement in the development of therapeutics targeting the melanocortin system. Here, we review the anatomy and function of the melanocortin system, discuss progress and challenges in developing melanocortin receptor-based therapeutics, and outline potential metabolic and behavioural disorders that could be addressed using pharmacological agents targeting these receptors.