薬理と治療

Abstract

Objectives Fifteen years have passed since the investigator‒initiated clinical trial was institutionalized in Japan. This analysis was conducted to capture the entire picture of investigator‒initiated clinical trials conducted to date, and to determine relevant facts and characteristics. Methods Using clinical study registry databases （e.g., University Hospital Medical Information Network［UMIN］, Japan Medical Association Center for Clinical Trials［JMACCT］）, investigator‒initiated clinical trials in Japan were identified. Information on clinical trial notification and others was also extracted. These data were analyzed to determine annual changes in the number of trials, as well as trial characteristics such as developmental phase, design, new active ingredient or new indication, and target disease. Results Between January 2003 and August 2017, 235 investigator‒initiated clinical trials were identified. Of these, 82.1％ were conducted in 2012 or later, and the annual number of trials increased from 2012 onward. PhaseⅡ accounted for 64.4％, but recent data showed an increase in PhaseⅠ trials（11 trials up to 2011 and 72 trials in and after 2012）. In addition to trials for new indications of approved drugs（24 trials up to 2011 and 99 trials in and after 2012）, seeding trials or trials of new active substances（15 trials up to 2011 and 94 trials in and after 2012）increased. Target diseases also have changed over time. Conclusions Recently, investigator‒initiated clinical trials have greatly increased and their contents have changed. This is presumably due largely to the influence of governmental policies including designation of core clinical research hospitals, and reorganization of pharmaceutical companies such as reduction of domestic development function in the age of globalization.