Delays in psychiatric drug development in Japan

Abstract

The lag in the approval and development of psychiatric drugs between Japan and other countries has been a major issue both for patients with psychiatric diseases and for psychiatrists. The objective of this study was to analyse factors contributing to delays in launching new psychiatric drugs in Japan. We analysed data from Japan, the USA, and the UK for the approval of 23 standard psychiatric drugs and examined potential factors that might have contributed the delay of their launch. Of the 23 standard psychiatric drugs, all of which were approved in the USA and the UK, only 13 were introduced in Japan between September 2000 and July 2011. None of their development strategies adopted the ICH E5 guideline on simultaneous development of drugs on a global scale. Twelve of the 13 drugs (not including atomoxetine) were approved in Japan after their approval in the USA and the UK. The median review time (from approval application to approval) of these 13 drugs in Japan was 23 months, which was considerably longer than those of the US Food and Drug Administration and European Medicines Agency (10·0 and 13·5 months, respectively). The 10-13-month difference in review time cannot explain the overall 87- and 51-month delay in Japan after approval in the USA or UK. There remains a large gap between Japan and Western countries, such as the USA and the UK, with regard to access to standard psychiatric drugs, despite several important reforms in the Japanese drug approval system.