Drug approval delays in hematologic malignancies between Europe and the US and between Japan and the US: a clinical...

Since novel therapeutic agents for malignancies are developed rapidly mainly in the US, the interval of approval timing between the US and other countries is an important issue. Among them, drugs for hematologic malignancies tended to have a particularly long delays in Japan, but its characteristics have not been fully understood. This study assessed the approval delays in drugs for hematologic malignancies in Japan compared with that in Europe.

Using the public database of Europe, Japan and the US, we analyzed the differences in drug approval delays between Europe and the US and between Japan and US according to disease. New molecular entity drugs for hematologic malignancies that were already approved in the US and were approved from April 2010 to March 2022 in Europe or Japan were identified.

The results showed the longer drug approval delays in Japan compared with that in Europe (29 vs. 9.4 months, median), presumably due to the lower proportion of participation in global clinical trials (37 vs. 94%). Notably, the participation rate in global clinical trials varied widely by disease in Japan, resulting in a greater difference in drug approval delays by disease. In contrast, when focusing on early phase trials, Japanese participation was uniformly very limited regardless of the disease.

The current study provided data that can be used as a basis for discussion on how to improve drug approval delays in drugs for hematologic malignancies.