PT-141 (Bremelanotide) is a synthetic peptide analog of alpha-melanocyte stimulating hormone (α-MSH). It acts as a non-selective agonist at melanocortin receptors 1, 3, 4, and 5. Approved by the FDA in 2019 for hypoactive sexual desire disorder (HSDD) in premenopausal women, it is the first drug approved for this indication that works on the central nervous system rather than peripheral blood flow.