Second Female Libido Drug Wins Approval

— Bremelanotide efficacy appears modest and made many patients sick in clinical trials

MedicalToday
BREMELANOTIDE (VYLEESI) over a photo of a frustrated tired looking woman in bed above FDA APPROVED

WASHINGTON -- Another drug for hypoactive sexual desire disorder (HSDD) in women, bremelanotide (Vyleesi), was .

Bremelanotide is an "on demand" peptide drug that stimulates the melanocortin receptor-4 and is delivered via an autoinjector pen, to be used at least 45 minutes prior to anticipated sex. The approval is restricted to premenopausal women.

Bremelanotide thus becomes the second drug to treat HSDD, after flibanserin.

Data from the phase III trials have yet to be published in a peer-reviewed journal. According to the FDA, manufacturer AMAG Pharmaceuticals conducted two 24-week, placebo-controlled trials involving some 1,250 premenopausal woman with acquired, generalized HSDD. "About 25% of patients treated with Vyleesi had an increase of 1.2 or more in their sexual desire score (scored on a range of 1.2 to 6.0, with higher scores indicating greater sexual desire) compared to about 17% of those who took placebo," the agency said.

"Additionally, about 35% of the patients treated with Vyleesi had a decrease of one or more in their distress score (scored on a range of zero to four, with higher scores indicating greater distress from low sexual desire) compared to about 31% of those who took placebo."

No difference between the active drug and placebo groups was seen in the change from baseline for satisfying sexual events, the FDA noted. On the other hand, that when trial participants were offered the option to continue receiving the drug in an open-label extension, nearly 80% accepted.

The FDA also said that most trial participants used bremelanotide "two or three times per month and no more than once a week."

As for safety, nausea was common with the drug -- seen in 40% of trial participants, with 13% needing medication to treat their nausea. A few patients also experienced darkening of their gums and certain areas of skin including face and breasts, which persisted when the drug was stopped.

Additionally, increases in blood pressure were seen after dosing. Although it typically resolved in 12 hours, the agency said bremelanotide should not be used in patients with uncontrolled blood pressure, known cardiovascular disease, or high risk to develop cardiovascular disease.

Given the apparently modest efficacy and the adverse effect profile, it's unclear whether bremelanotide will improve substantially on flibanserin. Sales of the latter drug, which also was clearly effective in only a small portion of patients, have been meager: that while prescriptions have been increasing, they still only reached about 3,000 in the U.S. during May 2019, versus about 1 million for the male sexual enhancer sildenafil (Viagra).