PT-141 (Bremelanotide): Research Overview, Mechanisms, and Current Evidence
PT-141 (bremelanotide) is a synthetic cyclic peptide and melanocortin receptor agonist, structurally related to melanotan II. It is approved by the US FDA as the prescription drug Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women, where it is given by subcutaneous injection as needed. Because it is a prescription drug, the framing here is research-use only. The information below summarizes published research for educational and research purposes only. It is not medical advice and is not guidance for use in humans.
Bremelanotide is a prescription drug. Available for research use from our preferred vendor, Project Zero. For laboratory research use only.
How It Works (Preclinical Mechanisms)
In research, PT-141 has been characterized as a melanocortin receptor agonist that acts on central pathways involved in sexual desire and arousal, rather than on the vascular system.
- Activates melanocortin receptors, with activity at the MC4 receptor linked to its effects on sexual desire.
- Reported to act through central nervous system pathways rather than directly on blood vessels.
- Derived from the broader melanocortin agonist melanotan II, but developed specifically for sexual-function research.
- Its melanocortin activity is also associated with side effects such as nausea, flushing, and transient blood pressure changes.
Areas of Research Interest
Published studies have examined PT-141 (bremelanotide) primarily in the context of female sexual dysfunction, where it progressed through registration trials.
Hypoactive sexual desire disorder
Studied in Phase II and Phase III trials in premenopausal women, leading to FDA approval as Vyleesi.
Female sexual arousal disorder
Investigated in dose-finding trials that included women with mixed desire and arousal symptoms.
Pharmacology and safety
Examined in Phase I studies for tolerability, drug interactions, and effects when combined with alcohol.
Melanocortin signaling
Studied as a tool to understand how central melanocortin pathways influence sexual response.
Reported Study Parameters
For laboratory research use only. The table below reports the doses and routes used in published clinical trials and approved labeling, with sources. It describes what was administered in those studies and is not a protocol, recommendation, or guidance for use in humans or animals. Because bremelanotide is a prescription drug, this information is provided for research context only.
| Research Model | Dose and Route Reported | Source |
|---|---|---|
| Premenopausal women with HSDD (Phase II dose-finding RCT) | 0.75, 1.25, or 1.75 mg self-administered subcutaneously, as desired, over 12 weeks | Clayton 2016·DOI |
| Approved labeling (bremelanotide, Vyleesi) | 1.75 mg subcutaneous as needed about 45 minutes before activity; no more than 1 dose per 24 hours and 8 doses per month, reported in clinical use | Mayer 2020·DOI |
| Human research (regulatory status) | FDA-approved as bremelanotide (Vyleesi) for HSDD in premenopausal women; a prescription drug provided here for research use only | Mayer 2020·DOI |
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Latest Research (2016 to 2020)
Peer-reviewed literature indexed on PubMed documents the trials that supported the approval of bremelanotide and characterized its dosing and safety.
Approval review
A 2020 review summarized the Phase II and Phase III data behind bremelanotide's approval for HSDD, reporting significant improvements in desire and reduced distress, with common adverse effects of nausea, flushing, and headache and a noted modest clinical benefit. PubMed·DOI
Phase II responder analyses
A 2019 analysis reported that the 1.75 mg dose achieved statistically significant responder rates across seven patient-reported endpoints versus placebo, and these definitions were carried into the Phase III RECONNECT registration trials. PubMed·DOI
Safety with alcohol (Phase I)
A 2017 Phase I crossover study reported that single intranasal 20 mg doses of bremelanotide given with or without alcohol were generally well tolerated, with no significant drug-related hypotensive effects in this setting. PubMed·DOI
Dose-finding trial
A 2016 randomized dose-finding trial in premenopausal women reported that pooled 1.25 and 1.75 mg subcutaneous doses significantly improved satisfying sexual events and sexual function scores versus placebo, with nausea, flushing, and headache as common adverse effects. PubMed·DOI
Research Questions
What is PT-141?
PT-141, or bremelanotide, is a melanocortin receptor agonist peptide related to melanotan II. It is approved as the prescription drug Vyleesi for HSDD in premenopausal women.
What is the current state of human evidence?
Bremelanotide completed Phase III registration trials and is FDA-approved for a specific indication. Trials showed statistically significant but modest improvements in sexual desire and distress.
What does the available safety literature suggest?
Common adverse effects include nausea, flushing, and headache, and the labeling limits dosing frequency. Because it is a prescription drug with defined risks, it should be used only under appropriate medical supervision and not self-administered.
Referenced Citations
Literature indexed on PubMed.
- Mayer, D., & Lynch, S.E. (2020). Bremelanotide: new drug approved for treating hypoactive sexual desire disorder. Ann. Pharmacother., 54(7), 684-690. PubMed·DOI
- Althof, S., et al. (2019). Responder analyses from a phase 2b dose-ranging study of bremelanotide. J. Sex. Med., 16(8), 1226-1235. PubMed·DOI
- Clayton, A.H., et al. (2017). Phase I randomized placebo-controlled, double-blind study of the safety and tolerability of bremelanotide coadministered with ethanol in healthy participants. Clin. Ther., 39(3), 514-526. PubMed·DOI
- Clayton, A.H., et al. (2016). Bremelanotide for female sexual dysfunctions in premenopausal women: a randomized, placebo-controlled dose-finding trial. Womens Health (Lond), 12(3), 325-337. PubMed·DOI
PeptideInfo.org provides information strictly for educational and research purposes. All referenced products are intended for laboratory and research use only and are not approved for human consumption, medical use, or self-administration. Nothing on this page constitutes medical advice. Research summaries reference literature indexed on PubMed.