Clinical Data Package for New Drugs in Japan
Kuniaki Yasuda (Senior Researcher, Pharmaceutical and Industrial Policy Research Institute)
Shunsuke Ono (Associate Professor, Department of Drug Evaluation Science, Graduate School of Pharmaceutical Sciences, The University of Tokyo)
(No.38: Published in March 2008)
This paper quantitatively clarifies the quality and quantity of clinical trial data pertaining to clinical trial results (clinical data packages) for new drugs approved between 2000 and 2006, which were used as the basis for the administrative decision of "approval" under the Pharmaceutical Affairs Law. The clinical data package for new drugs consisted of 11.0 studies and 992 cases per item (items containing new active ingredients), about one-fourth the number of studies and cases in the United States. The number of studies, number of cases, and study design of the clinical data packages varied greatly depending on the application category, review category, and drug classification, and the variation among the items increased further as the number of priority review designation items increased and the use of foreign studies progressed. Clinical data packages for new drugs were constructed in an environment where the number of cases in domestic trials was low. On the other hand, data packages using foreign studies are increasing, and the proportion of extrapolated comparative studies that allow rigorous evaluation of drug efficacy is increasing. Japanese data packages are smaller, and the number of domestic studies and cases per product is decreasing.
The criteria and requirements for the level of quality and quantity of clinical trials to be submitted as materials for regulatory approval are not always clearly defined in Japan. The Japanese regulatory authorities and the pharmaceutical industry need to cooperate with each other to establish general standards and requirements that can be applied to more situations. It is also important that the criteria/requirements that are ultimately adopted as the basis for individual approval decisions are not limited to those between the regulatory authorities and specific companies, but are made public in a manner that can be recognized as a signal to a wide range of interested parties. Furthermore, it is difficult to collect cases efficiently in domestic trials, and the infrastructure for conducting comparative trials that enable rigorous evaluation of drug efficacy is far from being fully developed. Unless domestic clinical trials become cost-effective for companies, there will inevitably be an increase in the number of companies building clinical data packages with a high proportion of foreign cases in the future. In order to improve the quality of efficacy evaluation in Japan, develop the domestic drug discovery and science and technology infrastructure, and promote international harmonization in the use of domestic clinical results in countries around the world, it is necessary to strengthen measures to further improve the environment for conducting domestic trials.