Crizotinib selectively inhibits the kinase activity of this tumor-specific fusion protein, The FDA granted accelerated approval for crizotinib in August 2011 for the treatment of EML4-ALK + NSCLC based upon a very positive phase I trial with two confirmatory single-arm phase 2 trials with a combined total of 255 patients [44]. This evidence concerns the gene EML4 and neoplasm.