Evaluation of Drug Lags in Development Initiation, New Drug Application and Approval Between Japan and the USA and the Impact of Local Versus Multi-regional Clinical Trials

Abstract

Background: Drug time lags occur between the date that new drugs are first approved, often in the USA, and approval is granted in other countries. Multi-regional clinical trials (MRCTs) are a key strategy for simultaneous global development and regulatory submission of new drugs. However, no studies have evaluated the impact of MRCT versus local development on key time points in the drug development lifecycle between the USA and Japan. It is important for pharmaceutical companies planning drug development in Japan to understand when they can start development, when they can catch up in case of development initiation delay, length of time the development period might take, and amount of time that market exclusivity is lost, if Japan does not participate in the MRCT. Objective: The aim of this study was to investigate differences in drug lag in development initiation, New Drug Application (NDA) submission and drug approval, as well as differences in the development and review periods, by local trials and MRCTs between Japan and the USA. We also assessed the advantages and disadvantages of MRCTs for these lags in Japan. Methods: We analyzed drug approvals in Japan between 2016 and 2020 and divided them into local and MRCT groups. Lags in development initiation, NDA submission, and approval of new drugs were calculated by subtracting each date in Japan from the corresponding date in the USA. Our study period was divided into three periods based on the International Conference on Harmonization (ICH) E17 guideline, published in 2017, and the guideline for the Phase I trials in the Japanese population prior to MRCTs, published in 2014. In addition, subgroup analyses by therapeutic area, regulatory background, modality, capital style, and sales ranking (2020) were conducted. Results: We analyzed 174 approvals in Japan and the USA. The differences in the drug lags for development initiation, NDA submission, and approval between the local and MRCT groups were 4.9, 3.5, and 3.2 years, respectively. All three lag times were shorter for the MRCT group than the local group. A development initiation lag in the local group has expanded since publication of the guidelines. Conclusions: For the people of Japan, important drug lags were identified in development initiation, NDA submission, and drug approval dates between local trials and MRCTs that include Japan. It is difficult to recover fully from the delay caused by local development, and it is important to understand the further expansion of drug lags, in cases where Japan is not involved in the MRCT.