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Sexual health peptide

PT-141

A melanocortin receptor agonist FDA-approved for low sexual desire in premenopausal women, self-administered by subcutaneous injection as needed.

By Cited Peptides Editorial Updated Medical review pending

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PT-141: key facts

In one sentence: PT-141 is an approved medicine (hypoactive sexual desire disorder in premenopausal women). Its strongest evidence is FDA approval backed by large trials, with 14 randomized trials listed on PubMed and 10 registered human trials.

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Why this evidence grade

FDA-approved

FDA-approved under the brand name Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women based on two pivotal Phase 3 trials (RECONNECT).

What it is

PT-141 (bremelanotide) is a synthetic cyclic heptapeptide analog of alpha-melanocyte-stimulating hormone (alpha-MSH). In June 2019, the US FDA approved subcutaneous bremelanotide autoinjectors (brand name Vyleesi) to treat acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. It is injected into the abdomen or thigh at least 45 minutes prior to anticipated sexual activity. While it was also investigated in men with erectile dysfunction, it is not FDA-approved for men.

How it is thought to work

Bremelanotide is a non-selective melanocortin receptor agonist that binds primarily to central melanocortin receptors MC3R and MC4R (and with lower affinity to MC1R and MC5R). Rather than acting on the vascular system like phosphodiesterase-5 inhibitors (such as sildenafil or tadalafil), bremelanotide acts in the central nervous system. Activation of hypothalamic and medial preoptic area MC4 receptors modulates downstream dopamine, norepinephrine, and serotonin release, thereby stimulating sexual desire and subjective arousal.

What the studies found5 studies explained

Efficacy was established in two identical Phase 3 randomized, double-blind, placebo-controlled trials (RECONNECT: Studies 301 and 302) involving 1,267 premenopausal women with HSDD over 24 weeks. Bremelanotide (1.75 mg SC PRN) produced statistically significant increases in sexual desire scores (FSFI-D) and significant reductions in distress scores (FSDS-DAO) compared to placebo. A 52-week open-label extension study confirmed maintained improvements with no new safety signals. Earlier clinical studies in men with erectile dysfunction who failed sildenafil showed increased erectile response, though clinical development focused on female HSDD.

Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials.

Kingsberg SA, Clayton AH, Portman D · Obstet Gynecol · 2019 · PMID 31599840

humanTwo double-blind, randomized, placebo-controlled phase 3 trials (RECONNECT: Studies 301 and 302)

Who / how many
1,267 premenopausal women with hypoactive sexual desire disorder (HSDD)
What they found
Subcutaneous bremelanotide 1.75 mg self-administered as needed produced statistically significant increases in sexual desire scores (FSFI-D mean difference 0.35 and 0.33, p < 0.001) and significant reductions in desire-related distress (FSDS-DAO, p < 0.001) compared with placebo over 24 weeks.
Limitations
Only enrolled premenopausal women with HSDD; event-driven dosing had an 8% discontinuation rate due to nausea. Did not show an increase in the number of satisfying sexual events compared to placebo.

Long-Term Safety and Efficacy of Bremelanotide for Hypoactive Sexual Desire Disorder.

Simon JA, Kingsberg SA, Portman D · Obstet Gynecol · 2019 · PMID 31599847

humanOpen-label, 52-week extension study of the phase 3 RECONNECT trials

Who / how many
684 premenopausal women with HSDD who completed the core 24-week trials
What they found
Clinically meaningful improvements in sexual desire and reduction in distress were maintained throughout 52 weeks of as-needed use, with no evidence of tachyphylaxis or unexpected late adverse events.
Limitations
Open-label design without a placebo control arm; susceptible to attrition bias because patients who experienced intolerable nausea in the core phase had already discontinued.

Safety Profile of Bremelanotide Across the Clinical Development Program.

Clayton AH, Kingsberg SA, Portman D · J Womens Health (Larchmt) · 2022 · PMID 35147466

humanIntegrated safety analysis across the clinical development program

Who / how many
2,746 women across seven clinical trials
What they found
Confirmed nausea (40.0%), flushing (20.3%), and headache (11.3%) as the most frequent adverse events. Blood pressure increases were small, transient (peaking 2-4 hours post-dose), and resolved within 12 hours. Hyperpigmentation occurred in 1.1% with frequent use.
Limitations
Post-hoc pooled analysis across Phase 1 to Phase 3 studies with varied dosing regimens.

Salvage of sildenafil failures with bremelanotide: a randomized, double-blind, placebo controlled study.

Safarinejad MR, Hosseini SY · J Urol · 2008 · PMID 18206919

humanRandomized, double-blind, placebo-controlled crossover trial

Who / how many
342 men with erectile dysfunction who had failed sildenafil therapy
What they found
Bremelanotide significantly increased erectile rigidity and duration compared to placebo, with successful intercourse reported in a substantial proportion of prior PDE5-inhibitor non-responders.
Limitations
Earlier formulation testing; transient blood pressure increases led the developer to halt development for male erectile dysfunction in favor of other indications.

Bremelanotide for female sexual dysfunctions in premenopausal women: a randomized, placebo-controlled dose-finding trial.

Clayton AH, Althof SE, Kingsberg S · Womens Health (Lond) · 2016 · PMID 27181790

humanMulticenter, randomized, double-blind, placebo-controlled phase 2b trial

Who / how many
394 premenopausal women with HSDD or female sexual arousal disorder (FSAD)
What they found
Demonstrated dose-dependent efficacy across 0.75 mg, 1.25 mg, and 1.75 mg subcutaneous doses, identifying 1.75 mg as providing optimal efficacy on desire and distress with acceptable tolerability.
Limitations
Dose-finding trial with a 16-week evaluation period; discontinued doses (0.75 mg) showed lower efficacy.

More published research (summaries coming)

Clinical trials10 registered

10 trials on ClinicalTrials.gov list PT-141 as an intervention; the most advanced are shown. Registration is not evidence of benefit: many trials are ongoing, unpublished or never reported results.

TrialPhaseStatusnSponsor
1. Study to Evaluate the Efficacy/Safety of Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder
NCT02333071 · results posted
Phase 3completed723Palatin Technologies, Inc
2. Study to Evaluate the Efficacy/Safety of Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder
NCT02338960 · results posted
Phase 3completed714Palatin Technologies, Inc
A Phase 3, Bridging, Multicenter, Randomized, Double-blind, Placebo-controlled, Parallel-group Trial to Evaluate the Efficacy and Safety of Subcutaneously Administered Bremelanotide in Premenopausal Women With Hypoactive Sexual Desire Disorder (With or Without Decreased Arousal)
NCT04943068
Phase 3completed193Kwang Dong Pharmaceutical co., ltd.
Bremelanotide in Premenopausal Women With Female Sexual Arousal Disorder and/or Hypoactive Sexual Desire Disorder
NCT01382719 · results posted
Phase 2completed612Palatin Technologies, Inc
A Phase 2 Study Evaluating the Co-Administration of Bremelanotide With Tirzepatide for the Treatment of Obesity
NCT06565611
Phase 2active not recruiting108Palatin Technologies, Inc
A Phase IIb, Multicenter, Open-Label, Prospective Study of Bremelanotide in Diabetic Kidney Disease
NCT05709444
Phase 2completed16Palatin Technologies, Inc
Evaluate the Safety and Efficacy of Bremelanotide in Women With Female Sexual Arousal Disorder (FSAD)
NCT00425256
Phase 2completedn/aPalatin Technologies, Inc
Study to Evaluate Rate of Nausea in Healthy Premenopausal Female Subjects Treated With Single Dose of Bremelanotide Alone or With Zofran
NCT03973047
Phase 1completed228AMAG Pharmaceuticals, Inc.
Role of the Melanocortin-4 Receptor in Hypoactive Sexual Desire Disorder
NCT04179734 · results posted
Phase 4completed40Imperial College Healthcare NHS Trust
Single Dose of Vyleesi in Lactating Female Subjects to Measure the Concentration of Bremelanotide in Breast Milk
NCT06867835
Phase 4completed10Cosette Pharmaceuticals, Inc.

Data pulled from the ClinicalTrials.gov API. Check sponsors: several newer peptide registrations come from companies that also sell the product.

European research

106 records in Europe PMC mention PT-141 in the title or abstract. Of the 25 most-cited with European author affiliations that we sampled, the most common countries were Italy (8), Spain (8), Czech Republic (2), Germany (2).

Search the EU registers directly: EU Clinical Trials Register (pre-2023 trials), CTIS (trials since 2022) and the EMA medicines database.

Side effects and risks

The most frequent side effect in clinical trials is nausea, occurring in roughly 40% of patients (and leading to discontinuation in about 8%). Nausea typically begins within an hour and lasts two to three hours. Other common side effects include flushing (20%), headache (11%), injection site reactions (13%), and nasal congestion. Bremelanotide causes a transient increase in blood pressure (averaging 2 to 4 mmHg systolic and diastolic) lasting up to 12 hours, making it contraindicated in patients with uncontrolled hypertension or cardiovascular disease. Focal hyperpigmentation of the face and gums occurred in approximately 1% of patients with repeated use.

Detailed PT-141 side effects & trial data →

United StatesFDA-approved in June 2019 (brand name Vyleesi, 1.75 mg/0.3 mL subcutaneous autoinjector) for HSDD in premenopausal women. Available by prescription only. Compounded and research-grade vials sold online are unauthorized.
CanadaNot approved by Health Canada. Bremelanotide is not marketed as an authorized prescription drug in Canada.
European UnionNot approved by the European Medicines Agency (EMA). Commercial authorization was not pursued in the EU.
Sport (WADA)Prohibited under Category S0 if sourced from unapproved or research preparations; athletes should check with their anti-doping authority.

Last verified . FDA Approval of Vyleesi (bremelanotide). WADA Prohibited List.

Common questions

What is PT-141 (Vyleesi) used for?

PT-141 (bremelanotide) is FDA-approved under the brand name Vyleesi to treat acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women. It is injected subcutaneously at least 45 minutes before sexual activity.

Does PT-141 work for men?

Clinical trials showed that bremelanotide can improve erectile response in men with erectile dysfunction, including those unresponsive to PDE5 inhibitors like Viagra. However, development focused on women, and it is not FDA-approved for men.

Why does PT-141 cause nausea?

Bremelanotide stimulates central melanocortin receptors, which activate emetic circuitry in the brainstem. In clinical trials, around 40% of patients experienced nausea, which was usually mild to moderate and resolved within a few hours.