Crizotinib was the first US Food and Drug Administration (FDA)-approved ALK tyrosine kinase inhibitor (TKI) and has high efficacy in locally advanced or metastatic NSCLC patients harboring ALK rearrangement, with response rates of approximately 60% across multiple studies and a median progression-free survival (PFS) of 8–10 months [4, 5]. The gene discussed is ALK; the disease is non-small cell lung carcinoma.