Friday Weird Science: Fibransin and the “problem” of female sex drive

Sci was toddling around the internet recently (as is her wont), when she came across the work of Dr. Petra. If you’re in to learning about sex, sex education, and everything else from a scientific point of view, Sci highly recommends Dr. Petra. This is a blogger who tells it like it is.
(Sci also just found out that Seed has a current article on humans as some very sexy beasts. Sci is suitably amused, and you should be too).
And it was an article from the awesome Dr. Petra which notified Sci of the current stuff going on with this drug called flibanserin, which has to be one of the WORST drug names. Sci keeps wanting to call it fibansin, or fibanserin, or flibansin. FLIBANSERIN?! Two syllables too many.
As you may know by now, the FDA rejected flibanserin for use in treatment of Hypoactive Sexual Desire Disorder (HSDD). Sci thinks this was extremely justified, as the results of the studies on flibanserin, first off, haven’t been PUBLISHED. This means they haven’t been peer reviewed. And there might be some good reasons. Neuroskeptic gave some great coverage of this. So far it looks like:

1) The trials did not show a statistically significant difference for the co-primary endpoint, the eDiary sexual desire score.
2) The Applicant’s request to use the FSFI [a questionnaire] desire items as the alternative instrument to evaluate the co-primary endpoint of sexual desire is not statistically justified and, in fact, was not supported by exploratory data from Study 511.77, which also failed to demonstrate a statistically significant treatment benefit on desire using the FSFI desire items.
3) The responder rates on the important efficacy endpoints for the flibanserin-treated subjects, intended to demonstrate the clinical meaningfulness, are only 3-15% greater than those in the placebo arm.
4) There were many significant medical and medication exclusion criteria for the efficacy trials, so it is not clear whether the safety and efficacy data from these trials are generalizable to the target population for the drug.

Um. Owie. So the whole thing was by questionnaire, which isn’t necessarily bad, except the questionnaire wasn’t itself proven to be any good. So then the results may not be any good. And the results they GOT suggest that even if the results WERE in fact an accurate representation, flibanserin doesn’t work any better than placebo. And even if it DID, there were so many exclusion criteria that we have no idea if the women used in the questionnaire even represented the regular target population. Excellent smackdown, FDA.
But there’s another deal here that Sci wishes to address, and that would be the issue of HSDD. Hold on to your hats.

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