Vyleesi (Bremelanotide) FDA Approval History

How Bremelanotide Reached FDA Approval

Bremelanotide's path from laboratory compound to approved drug took more than two decades. Palatin Technologies first identified the molecule as a synthetic peptide analog of alpha-melanocyte-stimulating hormone (alpha-MSH) in the late 1990s [1]. Early Phase 2 studies tested an intranasal formulation, but the FDA placed a clinical hold in 2008 after reports of blood pressure elevation with repeated nasal dosing [2]. Palatin then pivoted to a subcutaneous injection route at a lower fixed dose of 1.75 mg, which produced smaller and more transient blood pressure changes.

The FDA accepted Palatin's New Drug Application (NDA 210557) for priority review in February 2018 [3]. An advisory committee meeting on June 2, 2018, voted 14 to 10 in favor of approval, though several panelists raised concerns about the modest effect size and the 40% incidence of nausea [4]. The final approval came on June 21, 2019, making bremelanotide only the second FDA-approved pharmacotherapy for HSDD in premenopausal women, after flibanserin (Addyi), which had been approved in 2015 [5].

Dr. Hylton Joffe, then Director of the FDA's Division of Bone, Reproductive and Urologic Products, stated at approval: "There are women who have a low level of sexual desire that is troubling to them. We encourage continued research in this area" [5]. That measured endorsement reflected the agency's acknowledgment that HSDD treatment options remained limited.

The RECONNECT Trials: Key Efficacy Data

Two identically designed Phase 3 trials, RECONNECT 1 and RECONNECT 2 (combined enrollment N=1,247), formed the basis of the approval [6]. Both were randomized, double-blind, placebo-controlled studies lasting 24 weeks, conducted at sites across the United States and Canada. Participants were premenopausal women aged 21 and older with acquired, generalized HSDD as defined by DSM-IV-TR criteria, confirmed by a structured clinical interview.

The co-primary endpoints were change from baseline in the Female Sexual Distress Scale-Desire/Arousal/Orgasm (FSDS-DAO) Item 13 score (measuring distress related to low sexual desire) and the number of satisfying sexual events (SSEs) over 28 days. In the pooled analysis, women receiving bremelanotide 1.75 mg showed a statistically significant reduction in FSDS-DAO Item 13 score compared with placebo. The least-squares mean difference was -0.7 points (P<0.001) [6].

The SSE endpoint showed a more modest signal. The mean increase in SSEs was 0.5 more per month with bremelanotide versus placebo in the pooled data [6]. That difference reached statistical significance in RECONNECT 1 but not in RECONNECT 2 when analyzed individually. The FDA's statistical review noted this inconsistency but accepted the totality of the desire and distress endpoints as sufficient evidence [4].

A prespecified subgroup analysis found that treatment response did not vary significantly by age group, baseline SSE frequency, or duration of HSDD symptoms [6]. The 24-week study duration was longer than many sexual-medicine trials, though some reviewers questioned whether it captured the full trajectory of long-term use.

What the Vyleesi Label Specifies

The FDA-approved prescribing information carries several notable labeling features. The indication is narrowly drawn: acquired, generalized HSDD in premenopausal women [3]. The label explicitly states that Vyleesi is not indicated for treatment of HSDD in postmenopausal women or in men, nor for enhancement of sexual performance.

Dosing instructions specify a single 1.75 mg subcutaneous injection administered at least 45 minutes before anticipated sexual activity [3]. Patients should not inject more than once in 24 hours, and the label recommends no more than 8 doses per month. The 8-dose monthly cap reflects the limits of the safety database rather than a specific pharmacokinetic concern. Most participants in the RECONNECT trials used an average of 2 to 3 doses per month [6].

The label includes a Limitation of Use noting that the efficacy of Vyleesi beyond 24 weeks has not been established in controlled trials. A 12-month open-label extension study provided supportive safety data, but the FDA required this caveat given the absence of long-term placebo-controlled efficacy data [4].

Dr. Sheryl Kingsberg, a clinical psychologist at University Hospitals Cleveland Medical Center and RECONNECT investigator, described the on-demand dosing model in an interview with Obstetrics & Gynecology: "The ability to use this medication only when needed, rather than daily, aligns with how many women think about addressing their sexual concerns" [7].

Cardiovascular and Blood Pressure Considerations

Blood pressure elevation is the most clinically significant cardiovascular finding in the bremelanotide program. In the RECONNECT trials, bremelanotide produced a transient increase in systolic blood pressure of approximately 6 mmHg and diastolic blood pressure of approximately 3 mmHg, peaking around 2 to 4 hours after injection [3]. These changes resolved within 12 hours in most subjects.

The label contraindicates Vyleesi in patients with uncontrolled hypertension or known cardiovascular disease [3]. This boxed-warning-level precaution was the primary reason the advisory committee's vote was not unanimous. Patients with a resting blood pressure above 170/100 mmHg were excluded from clinical trials, so the safety profile in severe hypertension is unknown [4].

The FDA also required monitoring language: the prescribing information advises clinicians to assess cardiovascular risk before prescribing and to counsel patients about potential blood pressure effects [3]. For women already on antihypertensive therapy whose blood pressure is well controlled, the label does not absolutely prohibit use but advises caution and clinical judgment.

A 2020 post-hoc analysis published in The Journal of Sexual Medicine examined ambulatory blood pressure monitoring data from a subset of RECONNECT participants and confirmed that the mean increase was clinically mild and transient [8]. No serious cardiovascular events were attributed to bremelanotide in the combined trial program.

Nausea and Other Adverse Events

Nausea was the most frequently reported adverse event. In the pooled RECONNECT data, 40.0% of bremelanotide-treated women experienced nausea compared with 1.3% on placebo [6]. The nausea was most pronounced with the first dose. By the second and third injections, the incidence dropped to approximately 20% and continued to decline with subsequent dosing [3].

Other adverse events occurring at a rate of 3% or more (and at least twice the placebo rate) included flushing (20.3% vs. 0.8%), injection-site reactions (5.4% vs. 0.5%), and headache (11.3% vs. 6.5%) [6]. Hyperpigmentation, a predictable pharmacologic effect of melanocortin receptor activation, was reported in 1% of patients, primarily in the gingival area and on the face. The label advises that darkening of skin and gums may occur and may not fully reverse upon discontinuation [3].

The discontinuation rate due to adverse events was 8.9% in the bremelanotide group versus 0.4% in the placebo group across RECONNECT 1 and RECONNECT 2 [6]. Nausea accounted for the majority of treatment discontinuations. The antiemetic pretreatment strategy was not systematically studied in the Phase 3 program, though some investigators used it off-protocol in the open-label extension.

Post-Market Regulatory Actions and Label Updates

Since the June 2019 approval, the Vyleesi label has undergone minor revisions. The most significant post-approval development was not a safety signal but a commercial transition. AMAG Pharmaceuticals, which initially marketed the drug, was acquired by Covis Pharma Group in 2020 [9]. Covis restructured the commercial strategy, shifting toward specialty pharmacy distribution and direct-to-patient programs rather than broad retail pharmacy stocking.

The FDA Adverse Event Reporting System (FAERS) database, as of late 2025, has not flagged any new safety signals requiring a Risk Evaluation and Mitigation Strategy (REMS) or additional boxed warnings beyond the existing cardiovascular precaution [10]. No FDA Safety Communications have been issued for bremelanotide since approval.

The European Medicines Agency (EMA) has not approved bremelanotide. Palatin Technologies explored a European regulatory pathway but had not filed a Marketing Authorization Application as of early 2026 [1]. The absence of EMA approval means clinical experience outside North America remains limited to investigator-sponsored research protocols.

Comparison With the Only Other Approved HSDD Drug

Flibanserin (Addyi), approved in August 2015, was the first FDA-approved treatment for premenopausal HSDD [11]. The two drugs differ in almost every practical dimension. Flibanserin is a daily oral pill that acts on serotonin receptors (5-HT1A agonist and 5-HT2A antagonist). Bremelanotide is an on-demand subcutaneous injection acting on melanocortin receptors.

Flibanserin carries a boxed warning about severe hypotension and syncope when combined with alcohol or moderate-to-strong CYP3A4 inhibitors, and it requires a REMS program [11]. Bremelanotide has no alcohol interaction and no REMS, though it does carry the cardiovascular precaution described above. The choice between the two typically depends on patient preference regarding daily oral dosing versus on-demand injection, tolerance of alcohol restrictions, and individual response profiles.

No head-to-head trial comparing bremelanotide and flibanserin has been completed. A network meta-analysis published in 2021 in The Journal of Sexual Medicine suggested comparable effect sizes on desire endpoints, with different adverse-event profiles driving treatment selection [12].

Ongoing Research and Pipeline Considerations

Palatin Technologies has investigated bremelanotide in other populations, including postmenopausal women and men with HSDD, though no regulatory submissions for these indications have been filed [1]. A Phase 2b study in men with HSDD (NCT03017885) completed enrollment but results have not led to a Phase 3 program as of 2026.

Researchers at several academic centers have also explored bremelanotide's melanocortin pathway for potential applications in obesity and inflammatory conditions, though these programs are preclinical or early-phase and unrelated to the HSDD indication [13]. The MC4R target remains of broad pharmacologic interest beyond sexual medicine.

For clinicians prescribing Vyleesi today, the practical takeaway is straightforward: the approval rests on a well-defined dataset in a specific population (premenopausal women with acquired, generalized HSDD), with known and manageable side effects. Blood pressure should be assessed before prescribing, patients should be counseled about first-dose nausea, and the 8-dose monthly limit should be communicated at initiation.