Bremelanotide Long-Term Safety: What the RECONNECT Study Found
Understanding the safety profile of melanocortin receptor agonists requires examining controlled clinical trials rather than anecdotal claims. While unregulated products like melanotan I and melanotan II circulate online without regulatory approval or quality standards, related synthetic peptides have undergone formal clinical investigation. A primary reference point for extended exposure is a 2019 report published in Obstetrics and gynecology, which evaluated the long-term safety and efficacy of bremelanotide for hypoactive sexual desire disorder in premenopausal women. Examining the timeline, design, and outcome data of this single study provides clear insight into how the drug performed over extended use.
The Trial Background and Development Timeline
Bremelanotide was evaluated as a therapeutic option for premenopausal women experiencing hypoactive sexual desire disorder. To learn more about its clinical context, see our overview of bremelanotide and melanocortin medications. The long-term investigation emerged directly from the RECONNECT clinical program, which consisted of two parallel phase 3 trials designated as study 301 (ClinicalTrials.gov identifier NCT02333071) and study 302 (ClinicalTrials.gov identifier NCT02338960).
Both investigations initially featured a 24-week double-blind core phase that compared bremelanotide directly against a placebo. Patients who completed that initial phase without experiencing serious adverse events were offered entry into a 52-week open-label extension. The extension phase followed a specific timeline across both study branches:
- Study 301 open-label extension: Began on July 17, 2015, and concluded on July 13, 2017.
- Study 302 open-label extension: Began on October 5, 2015, and concluded on June 29, 2017.
Funding for the research was provided by Palatin Technologies, Inc., and AMAG Pharmaceuticals, Inc.
Study Design, Patient Participation, and Methodological Limits
When assessing medical literature, recognizing study limitations is just as important as reading the reported conclusions. This was a single open-label extension study rather than a blinded, placebo-controlled trial. Because participants and clinicians knew the active drug was being administered, expectations could influence subjective ratings. Furthermore, all statistical analyses conducted for the extension were descriptive.
Participation numbers also dropped substantially across the study timeline:
- 856 eligible patients completed the 24-week core phase.
- 684 of those eligible individuals elected to participate in the open-label extension.
- 272 participants completed the full 52-week extension period.
Because only 272 of the 684 enrolled women completed the entire 52-week extension, retention must be considered when evaluating long-term tolerability. Individuals who discontinued early may have experienced side effects or lack of perceived benefit, which can skew completed-cohort observations.
Observed Adverse Events Over Extended Use
All adverse events were systematically collected throughout the 52-week open-label extension. According to the published data in the PubMed record for the RECONNECT extension, researchers observed no new safety signals during the extended evaluation period. However, treatment-emergent adverse events were frequent.
The most common treatment-emergent adverse events considered related to the study drug were:
- Nausea, reported in 40.4% of participants
- Flushing, reported in 20.6% of participants
- Headache, reported in 12.0% of participants
The researchers noted that the only severe treatment-emergent adverse event experienced by more than one participant across both studies was nausea during the open-label extension.
Long-Term Patient Outcomes and Symptom Measures
Efficacy during the open-label extension was monitored using the coprimary endpoints established during the original core phase: the Female Sexual Function Index-desire domain score and the Female Sexual Distress Scale-Desire/Arousal/Orgasm item 13.
From baseline to the conclusion of the 52-week open-label extension, score changes varied depending on whether the participant received active drug or placebo during the earlier 24-week core phase:
- Participants on bremelanotide in the core phase: Changes in the Female Sexual Function Index-desire domain score ranged from 1.25 to 1.30, and changes on item 13 of the Female Sexual Distress Scale ranged from -1.4 to -1.7.
- Participants on placebo in the core phase: Changes in the desire domain score ranged from 0.70-0.77, while changes on item 13 reached -0.9.
The authors concluded that premenopausal women treated with bremelanotide exhibited sustained improvements in hypoactive sexual desire disorder symptoms without the emergence of unexpected safety issues.
Evaluating Regulated Data Versus Unregulated Peptides
The RECONNECT extension provides structured data on pharmaceutical bremelanotide, but its findings cannot be applied to illicit compounds sold online. Products marketed as melanotan I or melanotan II are unapproved, unregulated, and untested for purity or sterility. Anyone considering peptide therapies or experiencing health symptoms should consult a licensed doctor or dermatologist. For a broader overview of unregulated melanocortin products, read our guide on melanotan risks and side effects.
Sources
Published October 28, 2026. Sources are linked in the text. See our Medical Disclaimer.