Keywords: Clinical endpoint, locally-acting generic products
Clinical endpoint studies in Abbreviated New Drug Application (ANDA) are designed to evaluate two objectives: 1) The bioequivalence between a generic product and its reference listed product, i.e. the brand name drug in NDA; 2) The superiority of active treatment groups (generic and reference listed products) over placebo. The product specific guidance (PSGs) provide recommendations in terms of study design, primary endpoint and analysis population for the ANDA studies, but some of these recommendations differ from those for the reference listed product’s NDA study. A common challenge we encounter when reviewing these studies is that studies are designed following the recommendations in the PSGs, yet fail to show superiority or equivalence. We have encountered such failure for multiple products and multiple submissions for each product. Such results usually lead to a “complete response” decision, precluding the generic product in the market. In this presentation, we will evaluate the impact of study characteristics on the statistical outcome, including the choice of primary endpoint, analysis population and use of rescue medication. We aim to use the results of our investigation to develop internal consensus on the more efficient design of clinical endpoint studies.