FDA is Paper Tiger

Hampered by the lack of a comprehensive catalog of clinical trials, the FDA is unable to even identify all trials, the estimated 350,000 study sites and the institutional review boards that oversee each study to ensure they meet scientific, ethical and legal obligations, the report says.

Those limitations hinder the FDA's ability to ensure participants are protected from unreasonable risks, Levinson said.

The FDA relies on just 200 inspectors to police human studies of drugs and devices. The inspections they perform focus more on ensuring the accuracy of trial data than on verifying the measures put in place to protect the study participants, the investigation found.

Even when inspectors do turn up serious problems, their findings are frequently downgraded by senior officials and almost never followed by inspections to see whether the issues have been resolved, according to the report. In the case of the FDA's drug office, 68 percent of inspector recommendations that the agency take regulatory action, typically in the form of a warning letter, were downgraded.

Drug trials go unwatched, study says