● pepmg Research Desk · Peer-reviewed evidence review
What the research says about PT-141 (bremelanotide)
A neutral summary of the peer-reviewed literature on PT-141 (bremelanotide), a melanocortin-receptor agonist studied in phase 3 randomized trials for hypoactive sexual desire disorder in women, where the measured effects are statistically significant but modest and debated. Research use only.
Moderate evidence — Limited human trials — often early-phase. This describes the state of the published literature, not a claim that this compound works, is safe, or is for human use. Research use only.
The short version
- PT-141 (bremelanotide) is a melanocortin-receptor agonist approved by the US FDA and studied in two phase 3 randomized controlled trials for hypoactive sexual desire disorder in premenopausal women [1][3].
- The phase 3 RECONNECT trials reported statistically significant but modest improvements in a desire score and a reduction in distress versus placebo [1][2].
- Independent re-analyses reported that the measured benefits are small and of debated clinical meaning, and that discontinuation due to adverse events was substantially more common on bremelanotide [4][6].
- This page reports what the studies measured. It is not medical advice, an efficacy or safety claim, or dosing guidance. Research use only.
What PT-141 is
PT-141, known generically as bremelanotide, is described in the literature as a synthetic peptide analogue of the neuropeptide hormone alpha-melanocyte-stimulating hormone, with high affinity for the melanocortin type-4 receptor, a target thought to be involved in sexual response [3]. It was approved in the USA (marketed as Vyleesi) as a self-administered, on-demand subcutaneous therapy for premenopausal women with acquired, generalized hypoactive sexual desire disorder (HSDD) [3].
Material sold by third-party research-chemical vendors is not the approved pharmacy product and is offered for laboratory and research use only.
What the human research has measured
Moderate evidenceThe pivotal evidence comes from two identical phase 3, randomized, double-blind, placebo-controlled trials (RECONNECT) in premenopausal women with HSDD, testing a 1.75 mg subcutaneous dose taken as needed over 24 weeks [1]. Of the 1,267 women randomized, the trials reported statistically significant increases in a sexual-desire score (integrated change about 0.35, p<.001) and statistically significant reductions in distress related to low desire (integrated change about -0.33, p<.001) versus placebo [1]. A prespecified subgroup analysis reported that these improvements were broadly consistent across age, weight, and BMI subgroups [2], and an earlier phase 2b dose-ranging trial reported that the 1.75 mg dose reached statistical significance across its endpoints [7].
Separately, two phase 1 randomized trials in women with obesity reported that bremelanotide's activity at the melanocortin-4 receptor reduced caloric intake and produced a small short-term weight reduction (about -1.3 kg over 16 days versus placebo in one study) [8]. This receptor is involved in appetite regulation, which is why the compound has been examined for metabolic effects as well [8].
What the trials report on safety and adverse events
Moderate evidenceA safety review of bremelanotide's clinical development program (3500 subjects across 43 completed studies) reported that the most common adverse events in the integrated phase 3 studies were nausea (about 40.0% versus 1.3% on placebo), flushing (about 20.3%), and headache (about 11.3% versus 1.9%), and that nausea was the most common reason for discontinuation [5]. It also reported small, transient but statistically significant blood-pressure increases and noted that focal hyperpigmentation occurred in more than a third of subjects after repeated consecutive daily dosing, cautioning that the compound should be used with care in people at cardiovascular risk [5].
Independent re-analyses have scrutinized how these trials were reported. A meta-analysis based on the FDA New Drug Application reported that adverse-event-induced study discontinuation was substantially higher on bremelanotide (odds ratio about 11.98, 95% CI 3.74 to 38.37) and that, by a combined measure of completing the trial and electing the open-label extension, participants tended to prefer placebo [4]. A measurement-validity review reported that effect sizes across the trials' efficacy outcomes ranged from nil to small and that several prespecified outcomes were not published [6].
These are measured rates and analyses from controlled trials of an approved, pharmaceutical-grade medicine, not a safety guarantee and not a prediction for any individual. Material sold by research-chemical vendors is not that regulated product. This is not medical advice; consult a qualified professional and read the trials directly.
How strong is the evidence
The evidence base for PT-141 is characterized as moderate: its effects were measured in multiple phase 3 randomized controlled trials and pooled analyses, which is a high-quality design, but the measured benefits are modest and their clinical meaning is actively debated in the peer-reviewed literature [1][4][6]. "Moderate" describes the state of the evidence, not an endorsement, and it deliberately reflects both the positive trials and the critical re-analyses side by side.
Nothing here is dosing, medical, or safety guidance. Read the studies themselves and consult a qualified professional. This page is a map to the evidence, not a recommendation.
Sources · 8
- Bremelanotide for the treatment of hypoactive sexual desire disorder: two randomized phase 3 trials.
- Prespecified and integrated subgroup analyses from the RECONNECT phase 3 studies of bremelanotide.
- Bremelanotide: First Approval.
- Re-analyzing phase III bremelanotide trials for hypoactive sexual desire disorder in women.
- Safety profile of bremelanotide across the clinical development program.
- Small effects, questionable outcomes: bremelanotide for hypoactive sexual desire disorder.
- Responder analyses from a phase 2b dose-ranging study of bremelanotide.
- Effect of bremelanotide on body weight of obese women: data from two phase 1 randomized controlled trials.
pepmg summarizes the peer-reviewed literature and links to every source — it sells nothing, ships nothing, and gives no medical, dosing, or human-use guidance. Don't just trust this summary: follow any citation to its source and read it yourself. Research use only.