The Food and Drug Administration is once again considering the approval of flibanserin, a libido-boosting drug that has been called “female Viagra.” The final announcement could be one of the agency’s most controversial decisions of the year -- activist groups have accused panelists who have twice rejected the medicine of gender discrimination.

Sprout Pharmaceuticals, the drug’s maker, will present new data Thursday to two advisory panels in hopes of earning approval. At the crux of the controversy is whether the drug, which comes in a 100-mg pink tablet and is meant to be taken daily, is an effective treatment for hypoactive sexual desire disorder, which the Mayo Clinic defines as “a persistent or recurrent lack of interest in sex that causes you personal distress.”

Previous panels have pointed out that women who took the drug only showed small improvement in sex drive compared with those who took a placebo and cited safety concerns over side effects such as low blood pressure and fainting  as the reason for their rejection of the drug.

But women who struggle with a low sex drive say that the lack of approval is a sign of gender bias within the agency. Advocates point out there are more than 20 drugs for sexual dysfunction in men, but none for women. The agency has denied accusations of bias. 

Throughout the day, FDA advisors from the Bone, Reproductive and Urologic Drugs Advisory Committee and the Drug Safety and Risk Management Advisory Committee will hear presentations from Sprout Pharmaceuticals, patients and FDA scientists on the drug’s legitimacy. 

Dr. Hylton Joffe, director of the Division of Bone, Reproductive and Urologic Products opened his presentation by disputing the allegations of gender bias.

Representatives of Sprout, which is based in Raleigh, North Carolina, then began their argument by showing that rates of fainting (synoscope) and low blood pressure (hypotension) from flibanserin are no worse than those for other treatments that affect the central nervous system.

A live stream of the meeting is available here, and the panels are expected to make a decision on whether to approve flibanserin by 5:30 p.m. EDT.  

Update: The joint FDA panel voted 18 to 6 on Thursday to recommend the drug for approval, so long as safety precautions are taken to mitigate the risks.