Next‐generation ALK‐TKIs have been reported to overcome some secondary mutations mediating resistance to crizotinib.4, 24, 25, 26, 27 Importantly, each ALK‐TKI has different sensitivity to secondary mutations, and the clinical significance of rebiopsy to clarify the secondary mutation has been reported in various studies.5, 24, 25, 26 For instance, L1196M, which is a common gatekeeper mutation in ALK‐positive NSCLC, is resistant to crizotinib and sensitive to next generation ALK‐TKIs. The gene discussed is ALK; the disease is non-small cell lung carcinoma.