Response to Nature's editorial regarding the Japanese legal system for regenerative medicines.

Nature's editorial, dated 10 December 2015, made several criticisms of the new Japanese conditional and time-limited marketing authorization system for regenerative medical products. We believe these comments were based on a misunderstanding of the purpose of the regulations, which are patient-oriented, offering patients access to promising regenerative medicines in a timely manner at reasonable expense while also ensuring the efficacy and safety of the medicines. The new regulatory system represents an attempt by Japan to accommodate unmet medical needs, particularly for life-threatening diseases, and is in line with current global regulatory trends to enable early patient access to new therapies.