Notable Differences in Drug Lag Between Korea and Japan of New Drugs Between 2009 and 2017

Background: Although great efforts have been made to address delays in new-drug approvals between different regions, little is known regarding drug lag in Korea. We compared drug lag in Korea with that in Japan, which is well known through many previous studies.

Methods: We extracted approval information from public data obtained from the regulatory authorities on all new drugs that were listed in both Korea and Japan between 2009 and 2017. Relative drug lag represented the difference between the date of approval in the country of interest and the date of the first global approval. Relative drug lag was measured as median approval lag. Multiple regression models were used to identify the factors associated with drug lag. The factors considered included origin of substance, nationality of manufacturer, original approval date, orphan drug status, and therapeutic class.

Results: In total, 394 new drugs were approved in both countries between 2009 and 2017. The median approval lag was 28.2 and 54.1 months in Korea and Japan, respectively. Domestic company drugs were associated with longer median approval lag in Korea ([Formula: see text]), sensory organ drugs were associated with shorter median approval lag in Japan ([Formula: see text]), and orphan drug status was associated with longer duration of drug approval in Japan ([Formula: see text]).

Conclusions: Notable drug lags were observed in both Korea and Japan, but the lag was shorter in Korea. Inclusion of global clinical trials and existence of prior knowledge in new drug development were critical to reduce drug lag.