Clinical development and review times for new drugs in Japan: associated factors.

The length of clinical development and review procedures related to new drugs approved in Japan in 2000-2009 were analyzed. The length of time taken for clinical development varied depending on diversification of strategies, and the review times showed a decline during this period. Regression analyses suggested that clinical development times were significantly shorter for non-new molecular entities (non-NMEs), priority reviews, conditional approvals, and drugs utilizing foreign clinical data. The review times were shorter for new drug applications (NDAs) submitted to the Pharmaceuticals and Medical Devices Agency (PMDA) and for priority reviews. The effects of pre-NDA consultations were mixed; the review time was shorter, but the clinical development period was prolonged.