PT-141 (Bremelanotide): A Melanocortin Research Profile
PT-141 has something almost nothing else in a research-peptide catalogue has: a completed regulatory story. Under the name bremelanotide, this exact molecule was approved by the FDA in 2019. That history makes it a uniquely well-documented tool for studying the melanocortin receptor family – and a good case study in how research compounds and approved drugs differ.
The molecule
PT-141 is a cyclic heptapeptide analogue of alpha-melanocyte-stimulating hormone (α-MSH), developed from the earlier compound Melanotan II. The cyclisation (a lactam bridge) constrains its shape and gives it potent activity at melanocortin receptors – principally MC4R, with activity at MC1R and MC3R as well.
Why the melanocortin system interests researchers
The melanocortin receptors are a five-member family with strikingly divided labour: MC1R governs pigmentation, MC4R sits in hypothalamic circuits regulating appetite and autonomic function, and the others cover steroidogenesis and exocrine roles. A ligand like PT-141, with its well-characterised receptor profile, is a standard pharmacological probe for dissecting MC4R-mediated signalling in cell and animal models – receptor binding, downstream cAMP responses, and central pathway studies.
The development history, briefly
PT-141 began as a Palatin Technologies program and was ultimately approved as Vyleesi (bremelanotide injection) for hypoactive sexual desire disorder in premenopausal women. The approval belongs to that regulated pharmaceutical product – manufactured, dosed, and dispensed under drug law. Research-grade PT-141 is the peptide itself, supplied lyophilized for laboratory receptor work; it is not the drug product, and it is sold strictly for research use.
At the bench
A cyclic peptide with no free termini is comparatively robust, but standard practice still applies: reconstitute gently, refrigerate, plan concentrations with the calculator, and verify the lot on the COA lookup. PT-141 is available in the VitaPep catalogue with per-lot HPLC and MS verification.
All compounds supplied by VitaPep are for in-vitro laboratory research use only. Nothing on this page is guidance for human or veterinary use of any kind.
EDUCATIONAL CONTENT ON PUBLISHED RESEARCH · ALL VITAPEP PRODUCTS ARE FOR LABORATORY RESEARCH USE ONLY AND NOT FOR HUMAN OR VETERINARY USE.