OBJECTIVES:

The 2006 FDA-UDI was implemented to identify and remove unsafe/ ineffective drugs from the market. Manufacturers of such drugs could conduct studies to prove safety and/or efficacy and file a New Drug Application, for which approval provided limited market exclusivity. To date, there has been very little research on the potential consequences of this policy on post-approval prices and quantities sold for these drugs. This objective of this study was to assess the impact on prices and quantities sold for drugs that have been approved within the FDA-UDI in the US.

METHODS:

The DESI-II list prepared by the FDA Prescription Drug Wrap-Up program of 1984 was systematically searched to identify unapproved marketed drugs that were single-entity prescription drugs. For the drugs which obtained voluntary FDA approval within the FDA-UDI between 2006-2015, a retrospective longitudinal analysis was conducted based on the IMS Health National Sales Perspective database to analyze trends in total expenditures, units sold, and price/unit where all prices were adjusted to 2016 dollars.

RESULTS: Eighteen previously-marketed unapproved drug products were identified and 17 were included in the analysis (Neostigmine was excluded due to a shortage unrelated to the policy). Compared to the baseline price measured at two years pre-approval, 11 showed increases in the price/unit two years post-approval ranging from 27% to 8820%, while a decline in price was observed for the remaining six drugs. In addition, 12 showed a decline in quantity two years post-approval (range 2%-93%) while increases were observed for remaining five drugs. Substantial variance was also seen in the changes in expenditures, and in the implied price elasticities.

CONCLUSIONS: A marked increase was seen in post-approval prices along with decreases in quantities sold for most of the drugs approved in the FDA-UDI. However, the impact associated with the policy varied substantially across different drug products.