Germany's second-biggest pharmaceutical firm Boehringer Ingelheim announced Friday that it was halting the development of its sexual stimulant flibanserin, after the US Food and Drug Administration (FDA) found little evidence that it worked.

"The decision was not made lightly, considering the advanced stage of development," the company's board chairman Andreas Barner said in a statement.

Originally conceived as an anti-depressant, flibanserin began testing several years ago as a potential libido aid after some women in tests said it failed to help their depression but did boost their sex drive.

The pink-colored pill came to be known as "pink Viagra" or "Rosa Viagra," and clinical trials to test the drug's efficacy in raising sexual desire in pre-menopausal women were held in Canada, Europe and the United States.

But the FDA announced in June that in two US trials, in which the drug was compared with a placebo, flibanserin "failed to demonstrate a statistically significant improvement on the co-primary endpoint of sexual desire."

"Neither study met the agreed-upon criteria for success in establishing the efficacy of flibanserin for the treatment of HSDD (hypoactive sexual desire disorder)," the administration added.

As well as the poor results, the FDA noted that in some patients the drug caused side effects including depression and dizziness.

Company still believes in the drug

Barner said Boehringer Ingelheim was still convinced of the usefulness of the drug, which was to come on the market under the name "Girosa."

"The company continues to believe in the value that flibanserin would have for women suffering with HSDD, a significant and recognized medical condition which impacts the lives of many women around the world," Boehringer Ingelheim said in a statement.

But Boehringer Ingelheim's statement added the "complexity" of further questions meant that it had decided to reallocate resources to other projects.

Researchers believe lack of desire, or HSDD, is the most common sexual problem in women aged 30 to 60, just as erectile dysfunction is the most common sexual disorder among men in the same age bracket.

Boehringer Ingelheim say they will complete their two most advanced clinical studies to add knowledge on HSDD for the scientific community.

Author: Ben Knight (dpa, AFP, AP)
Editor: Cyrus Farivar