Time to Approval of 505(b)(2) NDAs is Shorter Than Conventional NDAs 
​[Posted on: Thursday, March 23, 2017]

A recent study by the Tuffs Center for the Study of Drug Development indicates that on an average the 505(b)(2) NDAs take about 5 months longer to get approval from the FDA compared to the new molecular entities (NMEs). However, this is an incomplete story. The authors of the survey specifically looked at the time to approval after the NDA was filed but not the total approval time beginning from the product development stages. The same group has previously published that NMEs take more than 10 years to develop and cost upwards of $2 billion to develop. Compared to that, the 505(b)(2) products take a fraction of the time (about 3-4 years) and cost much less to develop. The 505(b)(2) pathway remains a very popular development strategy for this reason. As the authors pointed out, most 505(b)(2) products are not eligible for the expedited approval pathways which increasingly apply to NMEs. About 80-90% of NMEs get at least one of the several expedited approval designations compared to less than 20% of the 505(b)(2)s. Also, due to the shorter time to NDA, the INDs for the 505(b)(2) applications move a lot faster at the FDA and require fewer meetings with the FDA. That in turn translates to the reviewers having more queries and the associated delays in decision regarding the NDA. Many 505(b)(2) development programs do not involve much preclinical testing and the clinical testing starts directly with Phase 2b and even Phase 3 clinical trials. On the other hand, NMEs almost always require extensive preclinical testing, and Phase 1 trials, and pre-IND discussions, all of which take a long time. A fair comparison between the approval times of 505(b)(2) and NMEs should take the whole time-line into consideration rather than the last step, namely the review of the NDA by FDA. The 505(b)(2) product developers should certainly improve their NDA review times by having pre-submission discussions with FDA (pre-IND, EOP2, pre-NDA, etc), to assure that their applications are reviewer-friendly and complete. Overall, we can comfortably assure, the 505(b)(2) products take less time to market compared to most NMEs.