Do Faster FDA Drug Reviews Adversely Affect Patient Safety? An Analysis of the 1992 Prescription Drug User Fee Act

times have significantly declined since the passage of PDUFA in 1992, while agency resources have expanded through user fees. After the recent withdrawal of Vioxx and other high-profile products, there have been increasing concerns that PDUFA has adversely affected drug safety. Combining several comprehensive databases, we analyze how FDA review time, drug novelty, and U.S. launch lag affect the occurrence of serious adverse events 1992-2002 U.S. new drug introductions. We find that more novel drugs and those with shorter U.S. launch lags have a larger number of serious events. After controlling for these and other factors, there is no association between FDA review time and adverse events. Many novel products, with significant anticipated benefits and risks, have black box warnings at the time of product launch. We find that black box warnings (except for pregnancy ones) are associated with more serious events. Notably, many serious adverse events involve rare occurrences that are not observable in pre-market clinical trials. Policymakers should consider our findings in future PDUFA changes, including dedicating a portion of user fees to post-marketing surveillance.