Melanocortin receptor agonist (bremelanotide) FDA-approved as Vyleesi® for hypoactive sexual desire disorder in premenopausal women.
Last Updated: May 2026
PT-141 (Bremelanotide) is a synthetic cyclic 7-amino-acid melanocortin receptor agonist FDA-approved as Vyleesi for the treatment of acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. It was derived from Melanotan II as a more selective MC4R agonist with reduced pigmentation effects. PT-141 is one of the few FDA-approved peptide compounds in the Peptigrity catalog, with substantial Phase 3 clinical evidence and active prescription distribution.
PT-141 (Bremelanotide) is a synthetic cyclic 7-amino-acid melanocortin receptor agonist derived from Melanotan II, with selective binding to MC4R (melanocortin receptor 4) in the central nervous system. MC4R activation in specific CNS regions modulates sexual desire and arousal pathways through dopaminergic and other neurotransmitter system effects. The selective receptor engagement produces sexual function effects with reduced pigmentation effects compared to the parent Melanotan II. Evidence level: FDA-approved (Vyleesi for HSDD); Phase 3 clinical evidence (RECONNECT trials).
In Phase 3 RECONNECT trials, PT-141 (Bremelanotide) produced statistically significant improvements in sexual desire and reduction in HSDD-related distress versus placebo in premenopausal women with HSDD, supporting FDA approval as Vyleesi in 2019. Effect sizes were modest but consistent. Approved use is as-needed subcutaneous administration before anticipated sexual activity. Evidence level: FDA-approved (Vyleesi 2019); Phase 3 RECONNECT trials; established prescribing information.
PT-141 is the selective MC4R agonist derived from Melanotan II as a focused sexual function compound. PT-141 has FDA approval (Vyleesi for HSDD) and a defined clinical use case; MT-2 has broader melanocortin receptor binding producing varied effects including pigmentation, sexual function, and appetite suppression.
| Compound | Mechanism | FDA status | Primary effect |
|---|---|---|---|
| PT-141 (Bremelanotide) | MC4R selective | FDA-approved (Vyleesi, HSDD) | Sexual desire |
| Melanotan II | MC1R + MC3R + MC4R + MC5R | Not approved | Pigmentation + sexual + appetite |
| Melanotan I | MC1R selective | EMA-approved (EPP) | Pigmentation |
The most common Vyleesi side effects in Phase 3 trials were nausea (40%), flushing (20%), injection-site reactions (13%), headache (11%), and vomiting (5%). Less common but clinically relevant side effects include transient blood pressure increases (which led to specific prescribing guidance about cardiovascular risk and dosing frequency) and rare reports of focal hyperpigmentation with repeated use. Discontinuation rates due to nausea were notable in trials. Evidence level: Phase 3 (RECONNECT) safety data extensive; FDA prescribing information detailed.
PT-141 (Bremelanotide) is FDA-approved as Vyleesi for hypoactive sexual desire disorder in premenopausal women. It is available by prescription through licensed pharmacies under specific prescribing parameters. Research-grade PT-141 is sold by third-party laboratories for laboratory use — that is distinct from the FDA-approved Vyleesi product. Regulatory context in are peptides legal regulatory status by country.
Because the FDA approval applies to Vyleesi specifically — not to research-grade PT-141 sold by third-party laboratories. Research-grade material is subject to wider purity variance, occasional underdosing, and inconsistent endotoxin control. The structural distinction between PT-141 and the related Melanotan II requires mass spectrometry verification — mislabeling between the two occurs in research-grade markets. Guidance in how-to-test-peptides hub.
Peptigrity purchases PT-141 vials anonymously at standard customer pricing, sends them to ISO-accredited third-party labs for HPLC and mass spectrometry analysis, and publishes the unedited certificate of analysis. Methodology in how we calculate trust scores.
PT-141 (Bremelanotide, Vyleesi) is FDA-approved for hypoactive sexual desire disorder in premenopausal women, acting through selective MC4R agonism to modulate central nervous system sexual desire pathways. It produces effects on sexual desire and arousal through CNS mechanisms rather than direct vascular effects.
Yes, as Vyleesi for hypoactive sexual desire disorder in premenopausal women. PT-141 is one of the few FDA-approved peptide compounds in the Peptigrity catalog. Research-grade PT-141 is distinct from the FDA-approved Vyleesi prescription product.
Vyleesi is available by prescription. Research-grade PT-141 is legal to purchase as a research chemical for laboratory use in most jurisdictions, but is not the FDA-approved prescription product. Country breakdown in peptide legal status guide.
PT-141 is the FDA-approved selective MC4R agonist derived from Melanotan II; MT-2 has broader receptor binding producing pigmentation effects as well as sexual function effects. PT-141 has the focused mechanism and regulatory approval; MT-2 has broader but unapproved effects.
The FDA approval is specifically for premenopausal women with HSDD. Research-grade PT-141 use in men is community-driven and not FDA-evaluated for male sexual function indications. Anyone considering use should consult a licensed physician about evidence-based options.
Independent third-party HPLC certificate of analysis from a lab the vendor does not own or pay, with mass spectrometry identity confirmation distinguishing PT-141 from the related Melanotan II. COA interpretation in red flags in peptide certificates of analysis.
No. The Vyleesi prescribing information specifies 1.75 mg subcutaneous as-needed up to 8 hours before anticipated sexual activity, with specific frequency limitations. Research-grade use is not FDA-approved. Peptigrity is an independent review platform, not a medical authority. Anyone considering PT-141 should consult a licensed physician about the prescription Vyleesi product.
This section is for educational and informational purposes only and does not constitute medical advice. PT-141 (Bremelanotide) is FDA-approved as Vyleesi for hypoactive sexual desire disorder in premenopausal women. Research-grade PT-141 sold for laboratory use is not the FDA-approved prescription product. Always consult a qualified healthcare provider before using any peptide or research compound. Peptigrity is an independent review platform and does not sell, endorse, or recommend specific products or vendors.
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