Pfizer has filed a new drug application for its oncology drug crizotinib with regulators in the U.S. and Japan.

Crizotinib, an oral first-in-class anaplastic lymphoma kinase (ALK) inhibitor, has been accepted for filing and granted priority review status by the FDA. It has also been submitted to the Japanese Ministry of Health, Labour and Welfare for the treatment of patients with ALK-positive advanced non-small cell lung cancer (NSCLC).

Results from an expansion cohort of a phase I/II trial showed that at eight weeks, 87% of patients given crizotinib had responded to treatment—57% of those experiencing tumor shrinkage. About 3%-5% of NSCLC patients have tumors that are positive for the ALK- fusion gene.