PT-141 (Bremelanotide) – 10mg

The first peptide in its class to win regulatory approval — PT-141 (bremelanotide) has a clinical pedigree that few research peptides can match. As a centrally-acting melanocortin agonist, it brought an entirely new mechanism to sexual response research, distinct from the peripheral vascular pathways targeted by the established small-molecule alternatives.

PT-141 is a synthetic cyclic heptapeptide and a melanocortin receptor agonist with preferential activity at MC4R. The MC4 receptor is expressed in hypothalamic regions involved in sexual response, appetite, and autonomic regulation — meaning PT-141 acts centrally to influence sexual response through neural mechanisms, not peripheral vasculature. Originally derived from research on Melanotan II, it was engineered to retain sexual-response effects while reducing the broader melanocortin activity (including pigmentation) characteristic of its parent.

PT-141 has received US regulatory approval for hypoactive sexual desire disorder in premenopausal women (under the trade name Vyleesi), distinguishing it from most research peptides. Its clinical pharmacology and safety profile are comparatively well characterised.

Sexual response: Phase 2 and Phase 3 trials in both female (HSDD) and male (erectile dysfunction) cohorts.
Central versus peripheral mechanisms: Studies positioning PT-141 within the broader landscape of sexual response pharmacology.
Melanocortin receptor pharmacology: Mechanistic research on MC4R signalling and downstream effects.
Cardiovascular profile: Studies examining blood pressure effects — an important consideration given MC4R's role in autonomic regulation.