At the time of this study, 5 EGFR-TKIs had been approved by the US Food and Drug Administration (FDA) for the treatment of EGFRm (Ex19del/L858R) advanced NSCLC: the first-generation erlotinib and gefitinib, the second-generation afatinib and dacomitinib, and the third-generation osimertinib.8 The gene discussed is EGFR; the disease is non-small cell lung carcinoma.