The landscape of CAR T-cell therapy in the United States and China: A comparative analysis.

The clinical trials of CAR T-cell therapy are growing fast in recent years, and most of the trials are initiated by sponsors from the United States and China. Exhibiting the distinctions between the clinical trials in the two countries is of great value for understanding the panorama of CAR T-cell clinical trials and forecasting the future of this promising therapy. We analyzed the critical elements of 289 clinical trials posted on the clinicaltrials.gov website by sponsors from the two countries and evaluated the efficacy data in available 50 published CAR T-cell studies. Our analysis shows that China has become the country with the largest number of CAR-T cell clinical trials by the end of 2017, while overall subject sample size and study center numbers are still larger, and the design of the clinical trials is more cautious in the United States. There are obvious differences between the two countries in CAR-targeted antigens in solid tumors and genetic modifications besides CARs for enhancing the potency of CAR T-cells. Although the currently available response rates are promising in both countries, it is inexpedient to conclude that the clinical efficacy is comparable between the two countries considering the smaller patient sample sizes and discrete distribution of median cell doses in China. And finally, the flexible regulatory regime of cell therapy in China, which expedites the bursting of CAR T-cell therapy, is also firstly introduced in our study.