Impact of the Clinical Trials Act on Noncommercial Clinical Research in Japan: An Interrupted Time-series Analysis

Background: The number of new noncommercial clinical studies conducted in Japan declined within the first year of the implementation of the Clinical Trials Act (CTA) on April 1, 2018. This study aimed to examine the impact of the CTA’s enforcement on the number of new noncommercial clinical studies registered in the Japanese Clinical Trial Registry. Methods: An interrupted time-series design was used in the analysis, which was conducted from April 2015 to March 2019. We collected data for studies registered in the Clinical Trial Registry, managed by the University Hospital Medical Information Network. Results: In total, 35, 811 studies were registered; of these, 16, 455 fulfilled the eligibility criteria. The difference in the trend of monthly number of new studies after CTA enforcement decreased significantly by 15.0 (95% confidence interval [CI], −18.7 to −11.3), and the level decreased by 40.8 (95% CI, −68.2 to −13.3) studies from the pre-enforcement to the post-enforcement period. Multigroup analyses indicated that the act exerted a significant effect on the trend of new clinical studies, particularly those with smaller sample sizes, interventional study designs, and nonprofit funding sponsors. Conclusions: The number of Japanese noncommercial clinical studies declined significantly following implementation of the CTA. It is necessary to establish a system to promote clinical studies in Japan while ensuring transparency and safety

High-dose Dexamethasone Therapy as the Initial Treatment for Idiopathic Thrombocytopenic Purpura: Protocol for a Multicenter, Open-label, Single Arm Trial

Standard therapy for idiopathic thrombocytopenic purpura (ITP) has not been established. We are conducting a multicenter, prospective trial to determine the efficacy and safety of short-term, high-dose dexamethasone therapy in ITP patients aged 18-80 years with platelet counts of <20, 000 /μL, or with <50, 000/ μL and bleeding symptoms. The primary endpoints of this trial are the proportion of responses (complete plus partial response) on day 180 (day 46+180) after the completion of the 46-day high-dose dexamethasone therapy. The results of this investigation of the effectiveness and safety of this regimen will be essential for the establishment of standard therapy for ITP

急性骨髄性白血病および骨髄異形成症候群の化学療法における経口ボリコナゾールの影響：国内後ろ向きコホート研究

京都大学0048新制・課程博士博士(社会健康医学)甲第22152号社医博第100号新制||社医||10(附属図書館)京都大学大学院医学研究科社会健康医学系専攻(主査)教授 川上 浩司, 教授 武藤 学, 教授 髙折 晃史学位規則第4条第1項該当Doctor of Public HealthKyoto UniversityDFA