Analysis of Review Times for Recent 505(b)(2) Applications

Annual review statistics released by the Food and Drug Administration (FDA) and a number of studies indicate that the review process improvements introduced under various versions of the Prescription Drug Use Fee Act (PDUFA) have been successful in decreasing average times for marketing approval of new molecular entities (NMEs). Similar statistics are not available, however, for non-NME new drug applications. These application types, such as those covered under section 505(b)(2) of the Food and Drug and Cosmetic Act, represent more than half of all new drug application (NDA) submissions annually and they are primarily based on previously approved drugs. To our knowledge, this is the first study to gather review statistics on 505(b)(2) designations.

For this study, we analyzed total review times and review designations for 284 505(b)(2) NDA approvals between 2009 and 2015.

Our results show that overall, the 505(b)(2) regulatory pathway results in longer review time than for NMEs despite the intent of the 505(b)(2) designation to simplify and streamline the review process. Several illustrative examples and the implications are discussed.

For drug developers, the important take home message is that-as for any program at the FDA-shorter review times and fewer FDA requirements under a 505(b)(2) designation should not be anticipated or expected. The study results serve as benchmark data providing insights into regulatory submission strategy and planning.