FDA wants more info on Pfizer's Fablyn

Pfizer has run into a roadblock at the FDA in its longrunning quest to gain an approval for its experimental osteoporosis drug Fablyn. The pharma giant says the FDA has asked for more information on the drug.

Fablyn has had a long and troubled history. It was rejected as a treatment for osteoporosis almost four years ago after the agency had determined that it could cause cancer in the lining of a woman's uterus. And it was rejected again in 2006 for vaginal atrophy.

But researchers at Pfizer decided to give it another try after reviewing the clinical trial data. And in a 9 to 3 vote an FDA advisory board determined that the drug's benefits outweighed its risks, saying that the drug appeared to be most effective in women with documented cases of osteoporosis.

"Pfizer is reviewing the letter and will work with FDA to determine the appropriate next steps regarding the company's application," the company said in a statement.

- check out the Pfizer release

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