PT-141: Research Overview and Mechanism
PT-141 (bremelanotide) is a cyclic melanocortin heptapeptide studied in laboratory research within melanocortin-receptor pharmacology, with reported agonist activity at melanocortin receptors including MC4R and MC1R, and within broader GPCR signaling models. It is the free-acid analog of Melanotan II, differing only at the C-terminus. As a molecule, bremelanotide is an approved drug marketed as Vyleesi for hypoactive sexual desire disorder, stated here as regulatory context only. It is supplied as a lyophilized powder for research use only and is not approved for human use.
What PT-141 is
PT-141 (bremelanotide) is a cyclic, N-acetylated melanocortin heptapeptide with a molecular weight near 1025.2 g/mol, closed by a lactam bridge between its aspartate and lysine side chains. Its sequence is closely related to Melanotan II, from which it differs only at the C-terminus: PT-141 terminates in a free acid where Melanotan II is amidated.
That single-atom difference makes the two a classic paired set for melanocortin structure-activity research, and it is also the identity feature that separates them on an analytical report.
Pathways it is studied within
In research, PT-141 is studied within melanocortin-receptor pharmacology as an agonist at melanocortin G-protein-coupled receptors, with particular attention to MC4R (a central melanocortin receptor) and MC1R. The constrained cyclic backbone is investigated for how conformational rigidity shapes receptor engagement in GPCR signaling models.
As a molecule, bremelanotide has a public regulatory record: it is approved under the brand name Vyleesi for hypoactive sexual desire disorder in premenopausal women, an approval supported by two Phase 3 randomized placebo-controlled trials reported in the peer-reviewed literature as the RECONNECT program. These statements describe the compound's regulatory status and the state of the research literature in the third person; they are not human-use claims for the material supplied here, which is for laboratory research only and is not approved for human use.
Handling and documentation
Pinnacle PT-141 ships as a 10mg lyophilized powder. Its tryptophan residue makes light protection the main handling point, since tryptophan is photosensitive, so the sealed vial is stored at -20C shielded from light before reconstitution.
Reconstitute with bacteriostatic water added gently against the vial wall and swirl rather than shake. Every batch is doctoral chemist tested by HPLC and mass spectrometry and ships with a lot-matched Certificate of Analysis confirming identity and purity of 99% or higher; because the free-acid terminus is the identity feature that separates PT-141 from Melanotan II, the observed mass on the COA is the fastest way to tell the two apart.
All products are intended strictly for in-vitro laboratory research and development use only. Not for human or veterinary use, not a drug, food, or cosmetic, and not intended to diagnose, treat, cure, or prevent any disease.