AmericanPeptide
Catalog/PT-141
ReproductiveFDA Approved

PT-141

Also known as Bremelanotide · Vyleesi

Melanocortin-4 receptor agonist FDA-approved for HSDD in premenopausal women.

Overview

Bremelanotide (PT-141) is a cyclic heptapeptide melanocortin agonist with preferential activity at MC4R. Approved by the FDA in 2019 for hypoactive sexual desire disorder in premenopausal women.

Background

PT-141 (bremelanotide) is a cyclic heptapeptide melanocortin agonist with preferential activity at the MC4R receptor. It is a metabolite of Melanotan II, refined away from pigmentation toward central sexual-response pathways.

Unlike vascular treatments for sexual dysfunction, PT-141 acts in the central nervous system on the circuits that govern desire and arousal. It is FDA-approved (Vyleesi, 2019) for hypoactive sexual desire disorder (HSDD) in premenopausal women.

Mechanism

MC4R-preferential melanocortin agonism in CNS sexual-response circuits.

Key research findings

  • Central arousal mechanism — a cyclic α-MSH analog acting on melanocortin MC3R / MC4R in the hypothalamus to drive sexual desire independent of the reproductive hormone axis (Molinoff / Diamond et al., 2003).
  • HSDD — FDA-approved (Vyleesi, 2019) for hypoactive sexual desire disorder in premenopausal women.
  • Distinct from vascular agents — acts on central desire circuits rather than on blood flow.
  • Compared to kisspeptin — PT-141 produces acute central arousal via melanocortin receptors, while kisspeptin acts upstream on the GnRH hormone axis; they address different research questions.
  • FDA-approved (Vyleesi) — for a specific indication.

How PT-141 is made

Behind every vial of PT-141 is the same exacting pipeline every research peptide runs — but the chemistry plays out differently for this molecule. Here is how PT-141, specifically, is brought into being.

  1. On paper first

    On paper, PT-141 is C50H68N14O10 — about 1,025.2 daltons of precisely arranged atoms. Before a single bond is made, the target sequence, salt form, and purity threshold are written down as the contract the finished material must meet.

  2. Built residue by residue

    PT-141 is assembled by solid-phase peptide synthesis — the chain grows one protected residue at a time on resin, and what you fail to build cleanly here you pay to remove later. It also carries cyclization, an extra step beyond a plain chain that adds both capability and cost.

  3. Purity is won here

    The crude mixture — PT-141 plus its deletions and side products — is then separated on preparative HPLC, and where the cut is taken decides the difference between a genuinely pure peptide and a barely-passable one.

  4. Proven, then protected

    A real batch of PT-141 proves itself: identity confirmed by mass spectrometry against its ~1,025.2 Da, purity read directly off an analytical HPLC trace, water and counterion content measured. That batch-specific certificate of analysis is the only honest way to know what is actually in a vial of PT-141 — and a short, cold, accountable chain of custody is how that purity survives the trip to your bench.

Walk the full synthesis pipeline

Handling, storage & why purity is hard

Producing PT-141 to a genuine purity spec means solid-phase synthesis, preparative HPLC purification, and batch quality control — none of it cheap, and none of it something you can verify by eye.

Don't judge a vial by its cake. A fluffy, good-looking lyophilized powder reflects bulking agents and freeze-drying parameters — not purity. Insist on a batch-specific certificate of analysis.

How peptides are made — the full pipeline

Research areas

  • HSDD
  • CNS sexual response
  • Ischemia models

Research-area guides

Latest research

Recent clinical trials and publications mentioning PT-141, pulled automatically from ClinicalTrials.gov and PubMed and refreshed daily. Listings are unfiltered search results, not curated endorsements.

Frequently asked questions

What is PT-141?+

PT-141 (bremelanotide) is a melanocortin MC4R agonist FDA-approved (Vyleesi) for hypoactive sexual desire disorder in premenopausal women.

How does it differ from erectile-dysfunction medications?+

Those act on blood flow; PT-141 acts centrally, on the brain circuits that govern sexual desire and arousal.

How is it related to Melanotan II?+

PT-141 is a metabolite of Melanotan II, refined toward MC4R and sexual-response activity and away from pigmentation.

Is this medical advice?+

No — this page is a research and educational reference, not medical advice.

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Ask the Agent about PT-141

Dosing protocols, mechanism, comparisons, and the latest trials — citation-backed answers grounded in PubMed, PubChem, and ClinicalTrials.gov.