Wyeth Pharmaceuticals, Collegeville, announced today that it received its third "approvable" letter from the FDA for a drug being developed for the treatment of postmenopausal osteoporosis.

The division of Wyeth received an approvable letter Wednesday from the Food and Drug Administration for bazedoxifene, which works like hormone therapy to strengthen bones to prevent osteoporosis, but is not a hormone, the company said.

The letter received this week applies to the use of the drug to treat postmenopausal osteoporosis.

The company had received two earlier letters - in April and December 2007, regarding use of the drug as a preventative measure.

Wyeth said that the letter issued Wednesday raised similar issues, and sought further analyses on the incidence of stroke and blood clots. The FDA also questioned some of the data collection and reporting, and requested additional source documents.

"Today's action is in line with our expectations," said Gary L. Stiles, executive vice president and chief medical officer of Wyeth Pharmaceuticals.

He said that Wyeth expected to file a response by the end of the year.

Company shares were trading at $43.55 late this morning on the New York Stock Exchange, down $0.33 from yesterday's close.