Assessing prescription medications for priority regulatory review

Poor concordance exists between medications that receive a priority review in Canada and those given an expeditious review in the United States. The objectives of this study were to obtain an evaluation of the clinical significance of new drugs approved in both countries from expert clinical pharmacologists, and to examine the concordance of their aggregate assessment with whether or not the product received an expeditious review in either country. Five experts assessed 146 new medications approved in both Canada and the United States between 1996 and early 2002. Overall, the concordance between the experts' assessments was poor and there was large variation in products considered to be of sufficient importance for priority status. Nevertheless, the experts' evaluations suggested that several priority-reviewed products did not warrant such a review. Regulatory agencies select new medications of potential clinical significance to receive shorter review times to minimize the delay in access to them, but, in Canada, only a low proportion of priority-status products had review times within Health Canada's performance target. The large variation in the assessment of clinical significance suggests that a more appropriate strategy in Canada is to devote sufficient resources to reviewing all medications in a timely manner.