PT-141: The Approval Buyers Do Not Know About

What was approved, and for whom?

PT-141 is the development code for bremelanotide, a synthetic melanocortin receptor agonist and a metabolite of Melanotan II. FDA approved it under new drug application 210557, effective June 21, 2019, as a single-use subcutaneous autoinjector ^[5]. The label's indication is the treatment of premenopausal women with acquired, generalized hypoactive sexual desire disorder, and its limitations of use state that the product is not indicated for that disorder in postmenopausal women or in men, and is not indicated to enhance sexual performance ^[4].

The product remains on the market. Drugs@FDA lists the one application, NDA 210557, now under the sponsor name Cosette, with the product VYLEESI (AUTOINJECTOR) ^[11]. That is the whole approved footprint: one indication, one population, one dosage form. The monograph records the dated ledger, and the approved page sets out what an approval does and does not cover.

What is the trial record behind the approval?

A completed development program, which is what distinguishes this molecule from almost everything else in this index. Across four names PubMed returns 121 indexed records, 91 tagged Humans, 16 under the clinical-trial publication type and 14 under the randomized type; all sixteen were opened, and one 2008 record carries a retraction marker in its own title ^[1]. Re-measured in September 2026 the counts are identical ^[10]. The trial record prints them beside every other molecule in the index.

The registrational evidence is two identical phase 3 trials, RECONNECT, in which 1,267 premenopausal women with hypoactive sexual desire disorder were randomized to 24 weeks of bremelanotide 1.75 mg as needed or placebo; 1,247 formed the safety population and 1,202 the efficacy population, most were white, from United States sites, with a mean age of 39. Sexual desire rose by 0.35 on the integrated desire score against placebo and distress fell by 0.33, both P<.001, and nausea, flushing and headache each occurred in 10% or more of treated women ^[3]. The dose-finding trial before it randomized 327 women across three doses and placebo over 12 weeks; the two higher doses pooled produced 0.7 additional satisfying sexual events a month against 0.2 on placebo (p = 0.0180) ^[8].

Those are modest effects on validated scales in a defined population, measured in trials whose sponsors are named in the paper, and they were sufficient for approval in that population. They say nothing about any other one.

What did the men's trials find, and why is there no men's indication?

The program began in men. A 2004 double-blind, placebo-controlled study evaluated intranasal PT-141 in healthy males and in patients with mild-to-moderate erectile dysfunction ^[2], and within the clinical-trial type the names combined with the terms erectile, men or male return 6 records, against 9 combined with the term premenopausal and 0 combined with the term postmenopausal ^[10]. The male work exists, in other words, and it is the older half of the file.

The only approval on the record is the women's indication ^[11], and the label states in terms that the product is not indicated for men ^[4]. Why a sponsor took one population forward and not the other is not on the record, and the record is what can be stated: the men's studies were run, that no approval followed them, and that a man buying PT-141 for the use those studies examined is buying for a use the approved product's own label excludes.

What does the safety record say?

An integrated review of the development program covers 3,500 subjects across 43 completed studies. In the double-blind phase 3 portion, 1,247 subjects, nausea occurred in 40.0% of treated women against 1.3% on placebo, flushing in 20.3% against 1.3%, headache in 11.3% against 1.9%, and injection-site reactions in 5.4% against 0.5%; nausea was the most common reason for stopping, and 70% of the bremelanotide group proceeded to the open-label phase against 87% of those on placebo ^[9].

Two findings bear directly on how the compound is sold outside its label. Focal hyperpigmentation was rare when the product was dosed as the label directs but occurred in more than one-third of subjects after up to 16 consecutive daily doses, and small transient rises in blood pressure were recorded on ambulatory monitoring, with the authors advising caution in patients at cardiovascular risk ^[9]. A buyer dosing a research vial daily for its pigmentation effect is reproducing the exposure that produced the first finding, without the monitoring that produced the second.

Is compounded or research-grade PT-141 the approved product?

No. Bremelanotide appears in no category of the section 503A bulks list published on May 14, 2026 ^[6]. In April 2020 FDA warned a compounding pharmacy that products it compounded using bremelanotide (PT-141) and twenty-one other substances were not eligible for the exemptions in section 503A(a) ^[7]; that letter predates the approval by ten months and its reasoning is not extended here past the date it was written, but it establishes that FDA has addressed compounded PT-141 directly.

A vial sold as PT-141 for research use is not the approved product and carries none of its assurances: not its manufacturing standard, not its dose, not its label, and not the safety record above, which was measured on the approved product at the approved dose. No supplier is listed for the molecule in this index, because no program has been verified as offering the approved product on its own product page. The approved peptide drugs table places bremelanotide beside the rest of the approved set, and Melanotan II, the parent it was derived from, shows in the melanocortins class what the same receptor family looks like with no development program completed at all.

Elsewhere in this index