This decision does not affect the current formulation of Requip (ropinirole hydrochloride) tablets, GSK said. An FDA approvable letter indicates that a drug may reach approval, but only after additional data are presented.

According to the company, Requip CR is an investigational extended-release formulation that is designed to provide a maximum of 14-hour coverage for those patients whose symptoms begin in the late afternoon or early evening hours. The company said it is committed to working with the FDA to address any questions or concerns the agency still has.