Additionally, Wyeth said it now expects to launch the oral contraceptive Lybrel early next year. In late June, Wyeth received conditional approval from the FDA for this drug, which is the first to eliminate menstrual periods.

The FDA wants more information about clinical trials and added data about manufacturing methods. The agency will convene a panel of experts to review the clinical trials. Wyeth said Wednesday that Lybrel's approval is contingent on the FDA endorsing changes at the Puerto Rico plant.

Wyeth also said it will delay the launch of an experimental depression drug, DVS-233, because it's conducting more clinical tests on a lower-dose version. The additional tests weren't ordered by the FDA, Essner said. Instead, they represent research that had been planned for some time.

The company is testing the drug for other uses, including symptoms of menopause, a form of chronic muscle and bone pain called fibromyalgia and chronic pain caused by damaged or injured nerve fibers.

Wyeth submitted its DVS-233 application for depression to the FDA in December, and company officials said they still expect to hear from the agency in October. However, they won't be able to evaluate the results of the additional clinical tests until early 2007. The company said it plans to launch the drug next year "with those lower-dose data available, subject to the FDA's approval" of Wyeth's application.