Abstract
We identified the major points that are described in the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) E17 guideline but have not been considered in the past multiregional clinical trials (MRCTs) used for drug approval in Japan to elucidate potential challenges in the implementation of the ICH E17 guideline in Japan. Based on the analysis of 167 MRCTs of 130 drugs, several points, such as the same dose setting and consistency between the overall and Japanese populations, in addition to good clinical practice compliance, have been well considered in ≥ 75% of MRCTs. In contrast, the use of relevant guidelines for disease and primary end point definitions, standardization of efficacy/safety information, sample size allocation, as well as training/validation on subject selection and primary end point, have been addressed less adequately and may need to be considered when planning future MRCTs. This study provides useful information for the implementation of the ICH E17 guideline in Japan.