PT-141 (Bremelanotide)

PT-141 (Bremelanotide) is a synthetic melanocortin receptor agonist that was developed from Melanotan II after researchers observed its effects on sexual arousal during pigmentation studies. Its pharmaceutical version (Vyleesi) received FDA approval in 2019 for hypoactive sexual desire disorder.

Unlike erectile dysfunction drugs (PDE5 inhibitors like sildenafil), which work on blood flow mechanics, PT-141 acts through the central nervous system by activating MC3R and MC4R receptors in the hypothalamus. This means it addresses the desire and arousal component of sexual function rather than just the mechanical response.

Clinical trials showed that PT-141 significantly increased the number of satisfying sexual events and improved scores on the Female Sexual Distress Scale. In male studies, it produced erections in men who did not respond to PDE5 inhibitors, suggesting a complementary mechanism.

PT-141's central mechanism of action makes it effective for both men and women, a significant advantage over peripherally-acting sexual health compounds.