Osimertinib, an oral irreversible third-generation EGFR TKI, is the standard of treatment in L8585 and classical del19 EGFR-mutated NSCLC in first-line metastatic setting on the basis of the results of FLAURA trial [10], as well as in second line after first or second generation EGFR TKI, in EGFR T790M positive NSCLC [12]. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.