Abstract
To address unresolved questions about drug safety and efficacy at the time of approval, the European Medicines Agency (EMA) may require that manufacturers conduct additional studies during the postmarketing period. As a growing proportion of new cancer drugs are approved on the basis of limited evidence of clinical benefit, timely completion of postmarketing requirements is important. We used publicly available regulatory documents to evaluate key characteristics of pivotal studies supporting EMA-approved cancer drugs from 2004-2014 and assessed completion rates of postmarketing data collection requirements after a minimum of 5 years. From 2004-2014, 79% (45/57) of EMA-approved cancer drugs had to fulfill postmarketing requirements. Pivotal trials supporting the approval of cancer drugs with postmarketing requirements were less likely to have randomized designs (41/61, 67% vs. 11/11, 100%), include an active comparator (20/61, 33% vs. 10/11, 91%), or measure overall survival as the primary study end point (18/61, 30% vs. 6/11, 55%) compared with pivotal trials for drugs without postmarketing requirements. Among 200 postmarketing requirements, almost half were designed to assess drug safety. After a minimum of 5 years, 60% (121/200) of requirements were completed, 10% (19/200) were ongoing, and 30% (60/200) were delayed. About half (40/75, 53%) of postmarketing requirements for new clinical studies were completed on time. Delays in the completion of postmarketing requirements often did not impact the likelihood of drugs receiving permanent marketing authorization (87%, 39/45) after 5 years. Our findings highlight the need for EMA to better enforce its authority to require timely completion of postmarketing requirements and studies.