Assessment of Drugs Approved by Public Knowledge-Based Applications (Kouchi-shinsei) During the Last Two Decades in Japan.

Public knowledge-based application ("Kouchi-shinsei" in Japanese) is unique to Japan, implemented to eliminate the off-label use of unapproved indications, dosages, and administrations because of drug lag. The guidance for public knowledge-based application was issued in 1999. This study comprehensively investigated the trends of items approved by public knowledge-based application in Japan during the last 2 decades. Prescription drugs approved from January 2000 to December 2019 were surveyed. In Japan, 1,855 drugs were approved within the target survey period. Among them, 219 (11.8%) were approved by public knowledge-based application. Considering the changes in the number of items approved by public knowledge-based application over the years, the number of items approved in 2000 was 7, reaching a maximum of 34 items in 2011, and decreased after that, 8 items were approved in 2019. The regulatory characteristics of drugs approved by public knowledge-based application and those of other drugs were compared. By public knowledge-based application, more anticancer and pediatric drugs were approved (P < 0.001), and only one drug for orphan diseases was approved (P < 0.001). In addition, the review time of public knowledge-based applications was significantly shorter than that of normal applications regardless of time point. The approval system using public knowledge-based application began in 2000, following issuance of the "Guidance for off-label use of prescription drugs." Furthermore, the approved items were mostly drugs for cancer, infectious diseases, and pediatric drugs. We anticipate the promotion of public knowledge-based application to accommodate the approval of drugs for orphan diseases.