Undercut by a harsh regulatory assessment on both safety and efficacy, Boehringer Ingelheim's female libido pill was handed a decisive rejection by an expert FDA panel on Friday. The experts voted unanimously that Boehringer had not demonstrated an acceptable risk/benefit profile for the drug, setting the stage for an all-but-certain formal rejection by the FDA.
FDA staffers had already concluded that the efficacy data on flibanserin's ability to stimulate women's sexual desire was not compelling. Coupled with only a "moderate" ranking for patient toleration and a 15 percent washout rate for women unable to continue treatment--compared to 6.8 percent of the placebo group--the side effects clearly proved a major obstacle for Boehringer. There was also added concern that patients' response to the drug could be adversely affected by both alcohol and antidepressants.
Often referred to as a kind of "female Viagra," flibanserin was actually targeted at women's brains, adjusting levels of serotonin as well as dopamine and norepinephrine. "The efficacy was not sufficiently robust to justify the risks," panel chair Julia Johnson, chief of obstetrics and gynecology at the University of Massachusetts Medical School, told reporters later.
While the FDA is not bound by the experts' opinions, it's unlikely that the agency would ignore a solidly opposed group of staffers and panelists. The drug has yet to be approved in any market.