(CNN) -- A Food and Drug Administration review of data on the effectiveness of flibanserin -- a pill anticipated to become the first "female Viagra" -- resulted in questions about how well the drug will actually work in treating premenopausal women suffering from low sex drive.

According to a report posted on the FDA website Wednesday, when compared with a placebo, the response rate of Flibanserin was "not compelling," and the drug yielded only slight improvements for treating hypoactive sexual desire disorder or HSDD.

On Friday, an FDA committee composed of reproductive health experts will be voting on the efficacy and safety of Flibanserin for use in women with low desire -- a sexual disorder that could impact nearly 40 percent of women in the United States, according to some estimates. Currently, there is no medication approved to treat HSDD in women.

A spokesperson for Germany-based Boehringer Ingelheim, the manufacturer of flibanserin, says the company is still optimistic.

"We remain confident that our data demonstrates Flibanserin is safe and effective in balancing the chemicals in the brain linked to sexual desire," says Peter Piliero, executive director of U.S. medical affairs for Boehringer Ingelheim. "We have conducted a robust program showing that flibanserin shows improvement increasing satisfying sexual events, in improving sexual desire and lowering distress," he adds.

Even if the data show only "slight improvements," the benefits of approving the drug are vast, contends Dr. Irwin Goldstein, director of sexual medicine at Alvarado Hospital in San Diego, California.

"HSDD is a horrible tragedy in women," says Goldstein, who treats patients suffering from low sex drive, and who has also been on the drug manufacturer's international advisory committee for several years. He says flibanserin would be "the beginning of an era" for women, and that having a safe and effective drugs is a "unique and historic opportunity for women in the U.S. and for the FDA."

CNN's Miriam Falco contributed to this report.