Overview
PT-141 is bremelanotide, a cyclic melanocortin agonist. The strongest evidence concerns acquired generalized HSDD in premenopausal women, where low desire is associated with distress and other causes are assessed1,5.
Approval belongs to VYLEESI and its specified indication. This compounded preparation is not the branded product, and the evidence does not establish an approved enhancement of sexual performance or benefit across all sexes and ages5.
Development & clinical program
The compound emerged from melanocortin research but is chemically distinct from Melanotan II. Its development focused on sexual-desire outcomes rather than cosmetic pigmentation5.
The clinical program progressed through dose-ranging and responder analyses to replicated blinded trials. These are substantially stronger than uncontrolled wellness reports, while still requiring interpretation of effect size and population1,3.
Mechanism of action
Bremelanotide binds multiple melanocortin subtypes; central MC4R-associated biology is relevant, but the label explicitly states that the exact mechanism improving HSDD is unknown5.
MC1R activity also links the drug to pigmentation, while gastric-emptying effects can alter oral-drug exposure. A central sexual-desire hypothesis does not mean the molecule acts only on desire5.
- 1Activates melanocortin receptorsBremelanotide is a cyclic melanocortin agonist, with activity at MC4R and MC1R most relevant at therapeutic doses5.
- 2Works in the brain, not on blood flowMC4R is expressed in brain circuits involved in sexual response, where bremelanotide is believed to act, rather than on vascular function5.
- 3Raises desire, lowers distressUsed as needed before sexual activity, it improved patient-reported desire and reduced desire-related distress versus placebo in both phase 3 trials1.
- 4Sustains over a yearIn a 52-week open-label extension, women who continued treatment maintained their desire and distress improvements2.
- Melanocortin receptors
- MC4R
- MC1R
- Central desire pathways
- Gastric emptying
RECONNECT & long-term data
RECONNECT randomized 1,267 women and used a 24-week blinded treatment period. The integrated desire-score difference versus placebo was +0.35, and the corresponding distress difference was -0.33; these are score differences, not percentage improvements1.
The label reports no significant between-group improvement in the number of satisfying sexual events, a relevant limit alongside the positive desire and distress measures. Not every measured sexual-function outcome improved5.
Of 684 women entering the open-label extension, 272 completed it. Continuing-participant findings and absence of a new signal do not remove the effects of attrition or establish long-term benefit for every patient2.
Replicated phase 3 results1
Both 24-week RECONNECT trials found improvements in desire and reductions in distress versus placebo.
Responders across every endpoint3
At 1.75 mg, responder rates beat placebo on all 7 patient-reported endpoints in phase 2b.
Benefit that lasts2
Desire scores improved by 1.25 to 1.30 points over 52 weeks among women who received bremelanotide from the start.
FDA-approved molecule5
Bremelanotide is approved as Vyleesi for premenopausal women with acquired, generalized hypoactive sexual desire disorder.
Cardiovascular & tolerability considerations
The branded label contraindicates use with uncontrolled hypertension or known cardiovascular disease. Nausea, flushing, headache and injection-site reactions are important tolerability issues5.
Persistent pigmentary changes and altered oral-drug absorption require attention; the label specifically warns about oral naltrexone exposure. Pregnancy, contraception and renal or hepatic concerns belong in a provider assessment5.
- The compounded preparation is not FDA-approved VYLEESI.
- Uncontrolled hypertension and known cardiovascular disease are branded-label contraindications [5].
- Nausea, flushing, headache and injection-site reactions can occur [5].
- Pigmentation may persist, and oral-drug interactions include naltrexone [5].
- Review pregnancy, contraception, renal or hepatic impairment and medicines with your provider.
Supply, storage & administration
VYLEESI is a ready-to-use subcutaneous liquid in a specific delivery device; this compounded vial is not that formulation5. Confirm whether the dispensed PT-141 is powder or liquid and use its own route, diluent and storage instructions.
The catalog specifies vial content, not a verified final formulation or storage specification. A lyophilized preparation requires the pharmacy-specified compatible diluent; a ready-to-use liquid does not. Follow the dispensing label for refrigeration, light protection and the beyond-use date, and use aseptic technique with a new sterile needle and syringe6. Dosing is set by your provider.
Questions
PT-141 or MT-2?
Bremelanotide is a distinct melanocortin agonist with a specific branded FDA-approved indication; Melanotan II does not share that approval.
Does approval include men?
No. The branded HSDD indication does not include men or postmenopausal women.
Is it a performance enhancer?
The approved label does not indicate it for enhanced sexual performance, and trial benefits concerned desire and distress.
Is the desire improvement a percentage?
No. The displayed difference is a patient-reported scale score relative to placebo.
Is compounded PT-141 identical to VYLEESI?
The active-molecule name does not establish equivalent formulation, delivery device, concentration, quality or exposure.
References
- 1.Phase 3 RCT
Kingsberg SA, Clayton AH, Portman D, et al.. Obstetrics and gynecology, 2019. PMID 31599840
Two 24-week trials randomized 1,267 women; integrated placebo-adjusted desire and distress differences were +0.35 and -0.33 score units.
- 2.Human study
Simon JA, Kingsberg SA, Portman D, et al.. Obstetrics and gynecology, 2019. PMID 31599847
The open-label extension enrolled 684 women and had 272 completers; nausea, flushing and headache were common.
- 3.Phase 2 RCT
Responder Analyses from a Phase 2b Dose-Ranging Study of Bremelanotide. (opens in a new tab)
Althof S, Derogatis LR, Greenberg S, et al.. The journal of sexual medicine, 2019. PMID 31277966
Responder analyses examined clinically meaningful patient-reported changes in dose-ranging research.
- 4.Phase 3 RCT
Simon JA, Kingsberg SA, Portman D, et al.. Journal of women's health (2002), 2022. PMID 35230162
Prespecified and integrated subgroup analyses explored the RECONNECT trial population.
- 5.Guidance / label
VYLEESI (bremelanotide) injection: prescribing information (opens in a new tab)
Cosette Pharmaceuticals; U.S. Food and Drug Administration. Regulatory guidance / prescribing information, 2024.
FDA prescribing information for Vyleesi: the premenopausal acquired, generalized HSDD indication, cardiovascular contraindications, and common effects including nausea and pigmentation.
- 6.Guidance / label
Preventing Unsafe Injection Practices (opens in a new tab)
Centers for Disease Control and Prevention. Regulatory guidance / prescribing information, 2024.
Use aseptic technique and a new sterile needle and syringe; opened multi-dose vials generally have a 28-day discard window unless the manufacturer specifies otherwise, never beyond original expiration.
Research summaries are educational and describe published studies, many in animal or cell models. They are not claims that this product treats any condition. Compounded medications are prepared by a licensed 503A pharmacy for individual patients and are not FDA-approved. Statements on this site have not been evaluated by the FDA. Products are dispensed only after review by a licensed provider. This site does not provide medical advice; talk to your provider before starting any therapy.