摘要：Early access to novel drugs, regardless of regional differences, is significant for patients worldwide. Although various efforts have been made to reduce the drug lag, it still exists in some regions, including Japan. In this study, we focused on the drug lag of first-in-class drugs in Japan and obtained fundamental information because we considered that first-in-class and me-too drugs are essentially different and should be treated separately. We analyzed 97 first-in-class and 176 me-too drugs in new molecular entity (NME)-approved drugs in Japan and the United States during the fiscal years between 2009 and 2019. Since government policy and the Evaluation Committee on Unapproved or Off-labeled Drugs with High Medical Needs (the Committee) have a huge impact on drug lag, we distinguished NMEs developed at the Committee’s request. First-in-class drugs were developed at the Committee’s request significantly more than the me-too drugs (p = 0.0034). Although it was not statistically significant, the approval lags were 498.0 d for first-in-class drugs and 535.0 d for me-too drugs. Multiple regression analysis showed that multi-regional clinical trial (MRCT) development strategy (p = 0.0043) and foreign origin drugs (p = 0.0072) were a reducing factor and a prolonging factor of drug lag, respectively. In conclusion, the drug lag for first-in-class drug approval was one year. Global drug development using MRCT is one of the most effective development strategies for reducing drug lags.
