Comparison of Oncology Drug Lag in Japan and South Korea Based on the Interval between the U.S. Approval and the Local Approval.

Drug lag is a serious issue for patients with life-threatening diseases such as cancer. Japan and Korea have been facing a large drug lag, despite having a large market and a good clinical trial environment. We analyzed drug lags for anticancer drugs between these countries, using the information on 82 anticancer drugs approved in the United States between 2017 and 2022. The national health insurance coverage status was also investigated. The approval lag, defined as the number of days from the date of approval in the United States to the date of approval in the country of interest, was used as the indicator of drug lag and was calculated for each drug. The median for all drugs was estimated using the Kaplan-Meier method, with the lag for locally unapproved drugs treated as censored data. The median approval lag in Japan and Korea for all drugs, including locally unapproved drugs, were 1547 d (4.2 years) and 1000 d (2.7 years), respectively. The approval lags for the approved drugs were 216 and 655 d in Japan and Korea, respectively. All drugs approved in Japan were covered by national health insurance whereas many drugs recently approved in Korea were not yet covered. The overall drug lag in Japan was greater than that in Korea due to the high number of unapproved drugs in Japan. In Korea, more drugs have been approved; however, it generally takes longer for them to become widely available to the public.