Bremelanotide Shows Promise as On-Demand Treatment for Hypoactive Sexual Desire Disorder

Melanocortin 4 receptor agonist meets phase 3 endpoints

Positive, statistically significant results have been reported from the phase 3 clinical trial program for bremelanotide (Palatin Technologies), an investigational on-demand treatment for premenopausal women diagnosed with hypoactive sexual desire disorder (HSDD). Two studies in the clinical program have met their pre-specified coprimary efficacy endpoints.

The randomized, double-blind, placebo-controlled trials compared bremelanotide with placebo in 1,267 premenopausal women with HSDD. The primary efficacy analysis population consisted of 1,202 women in the United States and Canada. The subjects self-administered 1.75 mg of either bremelanotide or placebo as needed in anticipation of sexual activity. The double-blind or efficacy portion of each study consisted of a 24-week evaluation period. The open-label safety extension portion of both studies is ongoing.

Based on discussions with the FDA, it was decided that the coprimary endpoints for the phase 3 clinical trials were the Female Sexual Function Index–Desire Domain (FSFI-D) and item 13 on the Female Sexual Distress Scale–Desires/Arousal/Orgasm (FSDS-DAO). Satisfying sexual events was a secondary endpoint. The FSFI-D is a patient-reported outcome measurement tool of sexual desire in the context of overall sexual function. The FSDS-DAO is a patient-reported outcome measurement tool of distress related to sexual dysfunction, measuring personal distress associated with low sexual desire.

In a preliminary review of the overall safety population (1,247 patients), bremelanotide appeared to be well tolerated. The most common adverse event was nausea, which was generally mild in severity. The safety profile of bremelanotide was consistent with prior clinical experience, and no new or unusual safety issues were identified.

Bremelanotide is being developed as a subcutaneous, on-demand, as-needed treatment for premenopausal women diagnosed with HSDD. Bremelanotide, which is a melanocortin 4 receptor agonist drug candidate, is a synthetic peptide analogue of the naturally occurring hormone alpha-MSH (melanocyte-stimulating hormone).

Source: Palatin Technologies; November 1, 2016.