Flibanserin (Addyi) is the first U.S. Food and Drug Administration-approved drug designed to help women with low sex drive. But that approval, announced in August, came with significant restrictions because the drug can cause severely low blood pressure and loss of consciousness, the FDA warned.
Addyi's label will include a boxed warning saying the drug shouldn't be taken while drinking alcohol, and shouldn't be used with certain other drugs and by women with liver problems.
And the once-daily pill, to be taken at night, can only be prescribed or dispensed by doctors and pharmacists who have been thoroughly briefed on the drug and its benefits and risks, the FDA added.
"Today's approval provides women distressed by their low sexual desire with an approved treatment option," Dr. Janet Woodcock, director of the FDA's Centre for Drug Evaluation and Research, said in a statement released Aug. 19.
"The FDA strives to protect and advance the health of women, and we are committed to supporting the development of safe and effective treatments for female sexual dysfunction."
Woodcock said Addyi will only be available through certified health care professionals and certified pharmacies "because of a potentially serious interaction with alcohol."
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Addyi is being marketed by Sprout Pharmaceuticals, based in Raleigh, N.C.
Dr. Holly Thacker, a women's health specialist at the Cleveland Clinic, said the FDA's approval of Addyi "provides an additional, helpful option for women across the country who experience sexual dysfunction. The medication has been studied in 11,000 women and it does improve sexual function in women who have certain sexual problems.
"It doesn't treat all sexual dysfunction, it won't help all women with sexual problems, but it will have a role in the therapy," Thacker added. "Just like with any medication adult women in conjunction with their physician can make an informed decision about whether this is an appropriate therapy for them."
Dr. Elizabeth Kavaler, a urologist at Lenox Hill Hospital in New York City, said: "Although the efficacy effectiveness of flibanserin is not clear, it seems to be safe. Couples will have the option of finding out for themselves whether or not it enhances their sexual relationship.
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It is clear that flibanserin will not address interpersonal or emotional problems. Nor will it address issues related to painful intercourse."The pursuit of a drug for women with low libido has been like a Holy Grail for the pharmaceutical industry, given the enormous popularity and financial windfall from the erectile dysfunction drugs Viagra and Cialis for men since the late 1990s.
And Addyi's long road to FDA approval it had been rejected twice by the agency since 2010 was a contested affair.
Proponents said the drug would provide an important option for millions of American women who suffer from hypoactive sexual desire disorder, which causes a persistent or recurring lack of desire.
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"This would bring another option to the table that doesn't currently exist," said Fred Wyand, spokesman for the American Sexual Health Association, a group that testified in favor of flibanserin during an FDA hearing in June.
But opponents cited a host of concerns about the drug. Among the concerns: symptoms of extreme fatigue and the potential for accidental injuries, as well as questions about the medication's effectiveness.
An FDA advisory panel voted 18 to 6 in June to recommend the drug's approval, but the endorsement was somewhat muted. The committee called the drug's benefits "moderate" or "marginal," and the panel members who voted yes said full FDA approval should come with conditions.
One of flibanserin's detractors is psychotherapist Keesha Ewers, founder and chief medical officer of the Functional Sexology Institute, who contends the drug hasn't been shown to be very effective.
Women in clinical trials for the drug reported, at best, an increase of one additional satisfying sexual event per month, according to FDA documents. Plus, clinical trials have also shown that the drug doesn't appear to directly boost a woman's libido, Ewers said.
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"Not one person in the studies that have been done has actually reported an increase in sexual desire," she told HealthDay. "What has been reported is a decrease in the distress that is felt about lack of sexual desire."
That distress is one of the clinical parameters used to diagnose a person with hypoactive sexual desire disorder. And that is what has allowed the drug's proponents to state that it can be useful in treating some women who have sexual dysfunction.
There are also some safety concerns about flibanserin. One in five women in clinical trials reported that the drug caused feelings of extreme fatigue and sedation.
Accidental injuries associated with this fatigue occurred twice as often in women taking flibanserin compared with those taking a placebo, FDA documents showed.
Flibanserin's backers mounted a marketing campaign called "Even the Score," which used a gender-rights argument to advocate for the drug's approval. The campaign received funding from Sprout Pharmaceuticals, Palatin Technologies and Trimel Pharmaceuticals, all of which are working on drugs to treat female sexual disorders.
A number of high-profile groups such as the National Organisation of Women signed onto the campaign, which argued that women deserve a medication that helps sexual function since men already have Viagra and Cialis.
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"We live in a culture that has historically discounted the importance of sexual pleasure and sexual desire for women," NOW President Terry O'Neill said in an NPR interview earlier this year. "And, I fear that it's that cultural attitude that men's sexual health is extremely important, but women's sexual health is not so important. "
Other groups in support of Even the Score included the American Sexual Health Association, the Association of Reproductive Health Professionals, the National Association of Clinical Nurse Specialists, the Society for Women's Health Research, and the Institute for Sexual Medicine.
"What makes me sad, worried, and to be honest, annoyed, is that there are no medical options available for women for whom biological factors are at play. Not one," said Lynn Barclay, the American Sexual Health Association's president and CEO, who testified before the FDA advisory committee in June.
Ewers said it's a false argument to compare flibanserin for women to Viagra or Cialis for men. Viagra works on a man's body, stimulating blood flow to create easy erections.
"That's an actual physiological function erection," she said. "It's not affecting their desire. It's affecting their plumbing."
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