Echinoderm microtubule-associated protein like 4 (EML4)-ALK, which is derived from the rearrangement of ALK and EML4 genes, has been validated as a therapeutic target in a subset of patients with NSCLC.     ///    "Finally, ASP3026 exhibited potent antitumor activity against cells expressing EML4-ALK with a mutation in the gatekeeper position (L1196M) that confers crizotinib resistance. "    ///    "In mice xenografted with NCI-H2228 cells expressing EML4-ALK, orally administered ASP3026 was well absorbed in tumor tissues, reaching concentrations >10-fold higher than those in plasma, and induced tumor regression with a wide therapeutic margin between efficacious and toxic doses. "