Health

With a ‘female Viagra’ now on the cusp of approval, is there any proof the disorder it’s targeting exists? By Ray Moynihan.

US FDA set to approve flibanserin, the ‘female Viagra’

Sex researcher Dr Alfred Kinsey, whose 1953 report declared women were very capable of enjoying sex.
Credit: GETTY IMAGES

A month ago, advisers to the world’s most powerful drug regulator met to consider approving a drug for a controversial “disorder” of low sexual desire in women. After reading the research and hearing testimony, the advisers made history by voting 18-6 in favour. If the United States Food and Drug Administration (FDA) accepts the advice – and it usually does – Australian authorities will likely follow, unleashing a tsunami of marketing for the new drug, and mass coverage of the disorder that goes with it.

Previous attempts to launch a so-called “pink Viagra” have all failed, dismally. More than a decade ago Viagra couldn’t beat a placebo or dummy pill in clinical trials with women. Testosterone was later rejected in the US because it barely beat the placebo, yet carried potentially nasty side effects.

Next came the drug flibanserin, a failed antidepressant to be taken daily, which backers claimed could boost libido. The FDA has already rejected flibanserin three times as a sex drug – in 2010, 2013 and 2014 – for similar reasons to testosterone. The evidence clearly showed the drug’s small and uncertain benefits did not outweigh a raft of side effects, including dizziness, sedation, fatigue and fainting.

Undeterred by the drug’s failure, the company now behind it, named Sprout, has come back again in 2015. This time it’s armed not only with new and slightly more favourable research evidence, but also with a massive company-funded public relations campaign that’s been running in the US, accusing the FDA of being sexist because it approves sex drugs for men, but not for women.

Untangling scientific facts from promotional fiction is difficult in medicine at the best of times, but when there’s a multibillion-dollar market at stake, the challenge becomes greater.

The reality is that this old antidepressant-turned-desire-drug has so far been tested largely in company-funded studies – in some cases with drug company employees actually working as researchers on those trials. And even in these company-sponsored studies – which are known to produce more favourable findings than independent trials – the drug has shown only marginal benefits compared with a placebo.

According to the most recent FDA summary of the evidence, taking the drug daily increased the number of “satisfying sexual events” experienced by women by between 0.5 and one event a month, compared with those on the placebo. These “events” are defined broadly and include intercourse or masturbation. In addition, women showed small improvements on scales that measure increased desire and reduced distress.

While these are said to be “statistically significant” results, there is great uncertainty over whether they have any real “clinical significance”.

On the “harms” side of the equation there is more certainty. According to the FDA analysis, flibanserin caused “central nervous system depression” in as many as one in five women, including sedation, sleepiness or fatigue. One FDA reviewer suggested that “with a drug known to cause sedating effects, like flibanserin, it is difficult to determine the extent to which sedation itself contributes to receptivity to sexual advances”.

Other common side effects included dizziness and insomnia, with rare cases of fainting and accidental injury. In one case, 11 days into one of the studies, a 34-year-old woman fell down, suffered concussion, and was admitted to hospital. It was unclear if this was due to the drug, but at least four other similar cases were deemed “causally related”.

Half an hour after taking her first dose, a healthy 33-year-old fainted and suffered “circulatory collapse” for two hours, with severe vomiting. Similarly, half an hour after her first dose, a 47-year-old became suddenly sleepy, began vomiting, and was unresponsive for a minute. After three days on the drug, a 41-year-old fainted one hour after taking her dose. Twenty minutes after taking a half dose, a 40-year-old fainted and experienced “circulatory collapse”.

To make matters worse, side effects are exacerbated if the drug is used with alcohol or certain common prescription medicines. One FDA reviewer concluded the low blood pressure and fainting associated with flibanserin when taken alone, or when used with alcohol, “can result in serious, irreversible, or life-threatening injuries”.

You may be wondering why any FDA adviser would vote yes to approve this drug. And it’s a question they asked themselves. Immediately following the vote at the June 4 hearing, the meeting transcript shows at least five advisers who voted yes pointing out the uncertain benefits and serious side effects of the drug they had only minutes before recommended for approval.

One adviser described it as having a “minimal effect of unclear clinical significance”. Another who voted yes observed, “it’s not a terribly effective drug … and safety concerns are significant”. One said the benefit was “not striking” while another noted “serious, serious, serious safety concerns”.

Many of the FDA advisers were clearly swayed by the argument that there’s a great “unmet need” for a drug to boost low libido, expressed poignantly by women who testified at the hearing. While for some women suffering can be severe, there are serious questions about whether the medical condition this drug is designed to treat – called hypoactive sexual desire disorder, or HSDD – actually exists.

According to the drug company’s PR campaign attacking the FDA – named “Even the Score” – 10 per cent of women have HSDD. It’s a claim we’ll probably hear a lot more of if the drug is launched in Australia. Yet the one-in-10 figure is based largely on the answer to a single survey question and it comes from a 2008 study funded directly by a German drug company hoping to win approval for its drug. All five authors were tied financially to the company, one being a company employee.

Notwithstanding the genuine suffering of some women, in serious scientific circles the idea of a widespread disorder of desire is largely discredited.

After reviewing all the scientific literature, more independent researchers have in recent years concluded a lack of spontaneous sexual desire is normal for most women, including those who enjoy their sex lives, and is not something that should be seen as a medical condition.

This new view has caused “HSDD” to be removed in the recent revision for the fifth edition of the US manual of disorders, the DSM-5, and merged into a new, much more tightly defined disorder combining problems of sexual interest and arousal. Dr Cynthia Graham, an internationally recognised sex researcher and one author of the new definition, told me frankly last year that HSDD “doesn’t exist anymore. There is no disorder of desire.”

Even more bizarrely, the company-funded Even the Score campaign is claiming 43 per cent of women have a sexual dysfunction. Yes, 43 per cent.

That figure comes from an old US survey that asked women if they experienced any of seven common problems over several months in the past year. Did they, for example, have a period of time when they’d lacked interest in sex, had troubled getting aroused or felt anxious about their performance? If a woman answered yes to just one of the seven items, she was categorised as having “female sexual dysfunction”.

The 43 per cent statistic confuses common difficulties with medical disorders, creates the impression of a massive “unmet need”, and builds billion-dollar markets. Yet the claim that half the female population suffer sexual dysfunction is eerily reminiscent of outdated medical thinking that could well backfire on those promoting it.

In 1950, one of the world’s most prestigious medical journals published an article stating 75 per cent of women derived little or no pleasure from sex which, according to the authors, was because in most cases the women were suffering a psychiatric condition called “frigidity”.

Three years later, the feminist classic The Second Sex was translated into English, with Simone de Beauvoir reminding us that women were still considered somehow less than normal and quoting Aristotle describing the female nature as being “afflicted with a natural defectiveness”.

That same year, 1953, Alfred Kinsey’s explosive report on women’s sexuality emerged, dismissing notions of widespread frigidity and finding women were very capable of enjoying sex. The problem was the way sex was happening for them, and the inadequacy of stimulation they were receiving from partners.

The campaign to promote flibanserin, if approved, will employ the forward-looking language of feminist empowerment, but it may in fact herald a dramatic shift backwards.

Ten years ago, when Viagra was still being touted for women, the men’s magazine Esquire featured a chilling quote from some anonymous everyman: “What’s up with the female Viagra?” he asked, and “Where can I get some for my girlfriend?”

 Little wonder libido may be low with that level of sensitivity.

This article was first published in the print edition of The Saturday Paper on Jul 4, 2015 as "Giddy with desire". Subscribe here.

Ray Moynihan
is an author and BMJ columnist, and a senior research fellow at Bond University.