ALK and non-small cell lung carcinoma: Crizotinib, a multi-targeted TKI with activity against MET, ALK, and ROS1, was the first ALK inhibitor to be approved by the U.S. Food and Drug Administration in 2011 for previously untreated metastatic ALK-rearranged NSCLC, based on results of a single-arm study that demonstrated an objective response rate of 61% [23].