PT-141 (bremelanotide), a synthetic alpha-MSH analog, induced erections in male animals and arousal in both sexes through central melanocortin MC3R/MC4R activation — the first centrally-acting peptide for sexual dysfunction.
Brain, not blood flowPT-141 works through the brain's desire centers (MC3R/MC4R), not peripheral blood flow like Viagra — effective when the problem is desire, not mechanics
What the researchers found
PT-141 (bremelanotide) induced sexual arousal in both male and female animals through central MC3R/MC4R activation, representing a mechanistically novel approach to sexual dysfunction treatment through brain desire pathways rather than peripheral blood flow.
Why it matters
Sexual dysfunction affects 40%+ of adults. Current drugs (Viagra) only address blood flow. PT-141 addresses desire/arousal centrally — helping patients where existing drugs fail.
How the study worked
Preclinical studies in male and female animal models. PT-141 administered centrally and peripherally. Erectile and arousal responses measured. Receptor specificity confirmed with selective antagonists.
What this study cannot tell us
Animal studies; human sexual dysfunction is more complex. Central peptide delivery may limit route options (intranasal or SC).
How to read the evidence
Moderate evidence from preclinical studies demonstrating clear central mechanism and both-sex efficacy.
When this study was published
Published in 2003. PT-141 (bremelanotide/Vyleesi) was FDA-approved in 2019 for hypoactive sexual desire disorder in premenopausal women.
The bigger picture
PT-141 (bremelanotide) was later approved by FDA as Vyleesi for hypoactive sexual desire disorder in women — the first melanocortin-based drug for sexual dysfunction, validating this research.
Questions still open
- Does PT-141 work in human clinical trials?
- Can a nasal spray or SC injection be practical for sexual dysfunction?
- Does the melanocortin mechanism avoid the cardiovascular risks of PDE5 inhibitors?
Common questions
What is PT-141/bremelanotide?
Is this approved for use?
Read the original research
PT-141: a melanocortin agonist for the treatment of sexual dysfunction.
Annals of the New York Academy of Sciences, 994, 96-102
Citation
Molinoff, P B; Shadiack, A M; Earle, D; Diamond, L E; Quon, C Y. (2003). PT-141: a melanocortin agonist for the treatment of sexual dysfunction.. Annals of the New York Academy of Sciences, 994, 96-102.