Food and Drug Administration officials have not done an adequate job of monitoring and enforcing timely completion of required post-market studies of certain drugs, according to a Government Accountability Office report.
The drugs in question received approval based on surrogate endpoints—laboratory measures such as lowering blood pressure—as opposed to more-direct clinical evidence such as preventing strokes. The FDA has approved 159 drugs based on surrogate endpoints since 1992 under a program that allows the agency to expedite approval of drugs designed to treat life-threatening illness or get drugs containing novel active ingredients onto the market. While the FDA has required makers of those drugs to conduct 319 post-market clinical trials, as of February 2009 only about half of those studies had been completed, the GAO found.
The GAO noted that while the FDA has taken steps to improve its oversight of post-market studies, it’s too soon to know the effectiveness of the agency’s efforts. The GAO report recommended that the FDA clarify its enforcement authorities and create clear standards for when it would move to withdraw a drug.