PT-141 clinical trials give a narrow but useful answer. In two studies called RECONNECT, bremelanotide produced modest average improvements in sexual desire and in distress about low desire compared with placebo. About 58% of treated women said they felt a meaningful benefit, versus about 36% on placebo. Nausea affected 40%. These results came from premenopausal women with a specific diagnosis, not men, everyone with low libido, or people using any PT-141 product.
What the PT-141 clinical trials asked
RECONNECT 301 and 302 asked the same question: over 24 weeks, did as-needed injected bremelanotide outperform a matching placebo in premenopausal women with acquired, generalized hypoactive sexual desire disorder? HSDD means persistently low desire that causes personal distress and is not better explained by a health condition, medication, relationship problem, or psychiatric condition.
The trials were randomized, meaning treatment was assigned by chance, and double-blind, meaning neither participants nor researchers knew who received the study drug. Their registry records are NCT02333071 and NCT02338960.
Together, the studies randomized 1,267 women: 635 to bremelanotide 1.75 mg and 632 to placebo. Participants were 19 to 56 years old, with an average age of 39. About 86% were white and nearly 97% were enrolled at U.S. sites. The narrow entry rules matter: these were otherwise healthy women with acquired, generalized HSDD, not every person who experiences low desire.
What RECONNECT measured
The two co-primary endpoints—the main outcomes chosen before the study began—were questionnaire scores. The Female Sexual Function Index desire domain, or FSFI-D, asks about the frequency and intensity of desire on a 1.2-to-6 scale; higher is better. Item 13 of the Female Sexual Distress Scale–Desire/Arousal/Orgasm, or FSDS-DAO, asks how often low desire felt bothersome on a 0-to-4 scale; lower is better.
That is an important frame. RECONNECT measured how women rated desire and distress, not a blood test or a count of orgasms. A separate secondary outcome counted satisfying sexual events.
RECONNECT trial results, in plain numbers
The 2019 RECONNECT paper reported statistically significant differences on both main outcomes. That means the gaps were unlikely to be explained by chance under the study's model; it does not mean the gaps were large.
| Outcome | Study 301 difference vs placebo | Study 302 difference vs placebo | Pooled difference |
|---|---|---|---|
| FSFI-D desire score | +0.30 | +0.42 | +0.35 |
| FSDS-DAO item 13 distress score | -0.37 | -0.29 | -0.33 |
The responder question is easier to picture. In Study 301, 58.3% of bremelanotide participants reported meaningful overall benefit, versus 36.1% on placebo. Study 302 was almost identical: 58.2% versus 35.4%. In other words, the treatment-placebo gap was about 22 percentage points, while the placebo response itself was substantial.
The satisfying-event count did not separate from placebo. Pooled change was 0.0 events with bremelanotide and -0.1 with placebo (P=.630). The honest headline is therefore more desire and less distress on average, not more satisfying encounters.
The side-effect table is part of the result
The pooled trial and current Vyleesi label put tolerability in clear numbers.
| Adverse reaction | Bremelanotide | Placebo |
|---|---|---|
| Nausea | 40.0% | 1.3% |
| Flushing | 20.3% | 0.3% |
| Injection-site reactions | 13.2% | 8.4% |
| Headache | 11.3% | 1.9% |
| Vomiting | 4.8% | 0.2% |
Overall, 18% of bremelanotide participants stopped because of adverse reactions, compared with 2% on placebo. Nausea alone led 8% to stop. The label also reports a temporary peak blood-pressure rise of up to 6 mmHg systolic and 3 mmHg diastolic, usually returning to baseline within 12 hours. Focal hyperpigmentation, meaning darkening in small areas of skin or gums, occurred in about 1% with intermittent use. The fuller safety context belongs in PT-141 side effects, while PT-141 dosage owns schedule decisions.
What the extension and later critics add
Of the 856 women who completed the blinded phase, 684 entered a 52-week open-label extension—everyone knew they were receiving bremelanotide. The 2019 extension report found sustained average questionnaire changes and no new safety signal. But only 272 participants, about 40% of those who entered, completed the extension. Without a placebo group and with that much dropout, it is useful mainly for longer exposure and safety, not a clean estimate of added benefit.
A 2023 independent reanalysis raised a different concern: the validity of the questionnaires and responder definitions for women with HSDD. It also found effects ranging from nil to small across several registered outcomes that the original paper had not fully reported. That critique does not erase the two positive primary endpoints. It does argue against turning modest group averages into a sweeping promise.
What the early studies in men can and cannot say
Men were studied, but not in RECONNECT. A 2004 Diamond trial tested intranasal PT-141 in healthy men and men with mild-to-moderate erectile dysfunction. A short laboratory measurement found greater erectile response than placebo at doses above 7 mg. A separate 2004 Rosen trial used subcutaneous PT-141 in healthy men and men who reported an inadequate response to sildenafil.
These were early, small studies measuring short-term penile rigidity, not modern phase 3 trials of lasting improvement or broad libido. The nasal program was later stopped after blood-pressure concerns, and Vyleesi's indication does not include men. PT-141 for men covers that evidence without borrowing the women's percentages.
Why the prescription route matters now
As of September 18, 2026, the day this article was written, an FDA warning letter dated August 24, 2026 had identified an online seller's PT-141 injectable as an unapproved new drug offered without an approved application. The agency also highlighted the risk of injectable products bypassing the body's defenses against toxins and microorganisms.
The letter was about that seller's products and claims. It did not change the RECONNECT results, and it did not say that a gray-market vial and an individually prescribed compounded medication are the same thing. A prescription route adds a named clinician, a licensed U.S. compounding pharmacy, a labeled preparation, and a path for questions or adverse-event reporting.
What these results mean for compounded PT-141
Promise's PT-141 is dispensed as a compounded medication, which is different from an FDA-approved product: the formulation offered here is not FDA-approved. The approved branded product is Vyleesi, the autoinjector studied in RECONNECT. Trial findings can inform a conversation about bremelanotide, but they cannot prove that a different finished formulation has identical quality, exposure, safety, or results.
The practical reading is careful, not dismissive: RECONNECT supports modest average changes in desire and distress for its enrolled population, alongside frequent nausea and meaningful study dropout. It does not settle the question for men or for every cause of low desire. How PT-141 works explains the brain pathway; this trial record explains how much confidence to place in the measured outcomes.
A licensed provider may still prescribe a compounded formulation when clinically appropriate; that decision is between the patient and the doctor. At Promise, a licensed provider reviews every request and prescribes only when PT-141 is medically appropriate; not everyone qualifies.
For what has changed since, including the label's status, FDA letters to online sellers and new studies, see the September 2026 PT-141 update.
