FDA Failing to Obtain Follow-Up Studies on Some Medications

Although FDA has authority to expedite removal of a drug from the market if a sponsor does not complete a required study—or if a study fails to confirm a drug's clinical benefit, it has not specified the conditions that would prompt it to do so, GAO said.

One of the examples is the case of Shire Laboratories'ProAmatine, a medication used for low blood pressure. The required study been incomplete since 1996. In its study, GAO found that ProAmatine had generated more than $257 million in sales up through 2008, even though "the clinical benefit of the drug has never been established."

FDA officials this summer indicated that they planned to issue a final administrative action letter to the sponsor of ProAmatine and generic manufacturers in a final effort to obtain completion of the required study, GAO said.