Drug companies made billions by tackling erectile dysfunction first with sildenafil (Viagra), approved in 1998, then tadalafil (Cialis) in 2003.
Sensing other potential blockbusters, pharmaceutical companies turned their attention to women with "bedroom" problems.
Define the Problem
The earliest official appearance of a condition involving lack of libido was in 1980, when the American Psychiatric Association . A 1987 revision changed the term to hypoactive sexual desire disorder (HSDD), though it would be another decade before drug firms evinced interest in it.
In 1999, an written by researchers with drug industry financial ties found 43% of women had some form of sexual dysfunction.
The data came from a 1992 survey by , of the University of Chicago, that was originally published in a 1994 textbook on sexual dysfunction. , a consultant to Pfizer and other drugmakers with an interest in sexual medicine, persuaded Laumann to publish it in article form.
"He told me it was imperative that we publish the data in a medical journal because doctors don't read books," Laumann said in an interview.
Rosen was as an author on the paper, which didn't list any conflicts of interest when it was originally published. When these were added later, two of the three authors disclosed financial ties to Pfizer.
In the late 1990s, researchers and drug companies met for a series of conferences in Massachusetts, including at Boston University, to talk about female sexual dysfunction.
Those meetings, which were detailed in a , set out to define sexual dysfunction in women and to determine how best to assess it in clinical trials. Many of the participants from those meetings eventually organized into the International Society for the Study of Women's Sexual Health, or ISSWSH.
In an email, ISSWSH declined to say how much funding it receives from the pharmaceutical industry.
Find a Solution
Meanwhile, a series of drug companies tried to get new products on the market.
Beginning as early as 2002, at least 10 drug companies conducted clinical trials of drugs ranging from testosterone to Viagra as possible treatments for lack of sexual desire in women, according to a Journal Sentinel/51˶ analysis of the federal government site .
Pfizer, the maker of Viagra, was one of the first to try -- hoping that its erectile dysfunction drug could have an effect on the female libido. But by 2004, several clinical trials showed Viagra had no impact on female sexuality, so the company pulled the plug on the project.
Next up was Procter & Gamble, known more for soap and shampoo than its pharmaceuticals.
The company that would address hypoactive sexual desire disorder in women.
Procter & Gamble also zeroed in on a specific population: women who had become menopausal because of a hysterectomy. Studies at the time showed 17% to 30% of the 10 million surgically menopausal women in the U.S. had hypoactive sexual desire disorder.
In 2004, an FDA advisory committee voted 17-0 against approval because there wasn't enough information on long-term safety.
Not long after, the German drug firm Boehringer Ingelheim sought approval for flibanserin, a drug that targeted serotonin, but failed to demonstrate efficacy as an antidepressant. Clinical trials, however, suggested that the drug might increase women's sexual desire.
Boehringer then funded the PRESIDE study, which not only focused on desire, but also on women's distress at having diminished libido.
That study used the Female Sexual Distress Scale -- a ratings system developed by Rosen, the Pfizer consultant -- to determine how bothered women were by their lack of desire. , it claimed 12% of women ages 20 to 49 had some form of dysfunction and were distressed by it. That amounts to 9 million women in the U.S. alone.
Is This Sexism?
The company was confident enough in its clinical trials program (it used feminine acronyms for the trials such as DAISY, VIOLET, and DAHLIA) that it sought FDA approval in 2010, but was turned down.
No longer willing to pursue getting it on the market, Boehringer Ingelheim sold the rights to the drug to the privately-held, 34-employee Sprout Pharmaceuticals of Raleigh, N.C.
Sprout CEO Cindy Whitehead and her husband Robert Whitehead knew the sexual medicine pharmaceuticals business well. In 2010, their company Slate Pharmaceuticals was hit with an .
In 2013, the American Psychiatric Association renamed the condition female sexual interest/arousal disorder. The committee that drafted the latest version of the association's Diagnostic and Statistical Manual (DSM-5) found it more accurately captured the wide variation in the psychological components of female sexuality.
That same year, flibanserin, under Sprout's banner, again failed to win FDA approval. That time the agency acknowledged that the drug had modest benefits compared with placebo, but those benefits did not outweigh the risks.
Next came an extensive political campaign that charged the agency with sexism for not approving a sexual medication for women, despite having many options for men on the market.
Much of the pressure came from the advocacy group "Even The Score," which was partially funded by Sprout, according to an April .
The group also convinced several lawmakers to sign on to a letter to then-FDA Commissioner Margaret Hamburg, MD, asking the agency to approve the drug, and started a .
Finally, in August 2015, the FDA approved the drug it had twice rejected. Now branded Addyi, touted by some as the "Female Viagra," the pink pill for women is counterpart to the blue pill for men.
Less than 48 hours later after the approval, Sprout and its product Addyi were sold to Valeant for $1 billion -- a figure analysts say was several times more than what Sprout was worth.
Valeant then set Addyi's price at $800 a month, about twice what Sprout had planned to sell it for.
Unlike erectile dysfunction drugs, Addyi will not be subject of consumer ads, at least for the next year or so. The company agreed not to embark on TV or radio advertising for 18 months following the Aug. 2015 approval date.
Valeant said it will instead focus on educating doctors on HSDD and determining which patients are appropriate candidates for the drug.