Tackling the Pharmaceutical Frontier: Regulation of Cannabinoid-Based Medicines in Postwar Japan.

Background: The valley of death, which refers to the gap due to the lack of support for the translation of basic research to related clinical studies, exists in the field of translational cannabinoid research in Japan owing to regulations. Article 4 of the Cannabis Control Act (CCA) of 1948 prohibits the use of Cannabis-based medicines. Objectives: This study aimed to explore the history of the establishment of regulations on the medical use of Cannabis-based medicines and discuss the current status of cannabinoid research and its regulation in Japan. Methods: We conducted a literature review of nationally archived official documents from the end of World War II in 1945 to 1948, which is the year the CCA was established. The documents were examined, specifically focusing on the sequence of events. Results: We found three memoranda related to the establishment of the CCA. The establishment of law on controlling narcotics was instructed by the general headquarters (GHQ)/Supreme Commander for the Allied Powers (SCAP) during the period of occupation after World War II. However, the Japanese Government decided to regulate Cannabis separately from other narcotics. Item (ii) of article 4 in the CCA, which prohibits medical application of Cannabis, was included to protect farmers growing Cannabis for the hemp content. Conclusion: Current Japanese regulations prohibiting clinical research in phytocannabinoids were instituted during the postwar era of World War II. Scientific discoveries have advanced cannabinoid research and have led positive reforms of the regulation of Cannabis in other countries. Therefore, there is ample motivation and opportunity for Japanese stakeholders to revise article 4 of the CCA for the benefit of patients.