PT-141

PT-141 (bremelanotide) is a synthetic cyclic 7-amino-acid peptide that activates the melanocortin 3 and 4 receptors (MC3R / MC4R) in the central nervous system. It is FDA-approved under the brand Vyleesi for the treatment of acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women, approved June 2019.

Peppudex card: see the mechanism + evidence-grade summary at [Peppudex / PT-141](https://peppudex.com/peptides/pt-141).

Overview

PT-141 was originally developed from melanotan-II by Palatin Technologies as a non-PDE5-pathway treatment for sexual dysfunction. Unlike sildenafil/tadalafil (which act on the vascular/erectile pathway), bremelanotide acts centrally through melanocortin signaling on sexual arousal.

The sequence is Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH.

Mechanism

PT-141 is a non-selective melanocortin 3/4 receptor agonist with preferential MC4R activity in the hypothalamus. MC4R activation drives the release of dopamine in the paraventricular nucleus and oxytocin, both of which mediate central sexual arousal pathways.

See: Nitric_oxide_signaling (downstream secondary effects).

Evidence

Clinical evidence supporting Vyleesi approval:

• RECONNECT-1 and RECONNECT-2 · Phase 3 trials in premenopausal women with HSDD demonstrated improvement in Female Sexual Function Index desire score (Kingsberg et al., Obstet Gynecol 2019; PMID 31022173).
• Erectile dysfunction trials · Phase 2 trials in men with ED showed efficacy but Palatin pivoted to female HSDD given regulatory considerations.

The clinically relevant adverse-event profile includes transient nausea (most common), facial flushing, and transient blood pressure elevation (~6 mmHg systolic). Vyleesi is contraindicated in uncontrolled hypertension.

Dosing literature

Vyleesi is dosed as a single subcutaneous 1.75 mg injection administered at least 45 minutes before anticipated sexual activity. The wiki does not recommend any off-label dose; clinical dosing is per the Vyleesi label.

Pharmacokinetics

PT-141 plasma half-life is approximately 2 hours after subcutaneous injection. Tmax occurs around 1 hour post-dose. The Vyleesi label recommends administration 45 minutes before anticipated sexual activity to align with the pharmacokinetic peak. The peptide is cleared primarily renally with minor hepatic metabolism.

Storage

Vyleesi is packaged as a pre-filled autoinjector and stored at room temperature. Research-grade lyophilized PT-141 is stable at –20 °C for at least 24 months. After reconstitution with bacteriostatic water, store at 2-8 °C and use within 28 days.

Regulatory status

• United States. FDA-approved as Vyleesi for HSDD in premenopausal women (June 2019). Distributed by Palatin Technologies / AMAG / Cosette.
• European Union. Not approved as of 2026-05.
• WADA. Not listed on the 2024 Prohibited List.

Side effects (per Vyleesi label)

• Nausea (most common, ~40 percent of users in pivotal trials)
• Facial flushing
• Headache
• Transient blood pressure elevation (~6 mmHg systolic) lasting 8 to 12 hours
• Focal hyperpigmentation with chronic use (off-target MC1R activity)
• Injection-site reactions
• Contraindicated in uncontrolled hypertension and pre-existing cardiovascular disease

See also

• Reconstitution · vial-prep math
• [Peppudex card · PT-141](https://peppudex.com/peptides/pt-141) · mechanism, evidence grades A-F, FAQs, peer-reviewed sources

References

• Kingsberg SA, et al. "Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials." Obstet Gynecol. 2019;134(5):899-908. PMID 31022173.
• Clayton AH, et al. "Bremelanotide for female sexual dysfunctions in premenopausal women: a randomized, placebo-controlled dose-finding trial." Womens Health (Lond). 2016;12(3):325-37. PMID 27193591.