EGFR and non-small cell lung carcinoma: It can target both the initial EGFR mutation and the T790M site mutation at the same time, and it is used to treat patients with NSCLC and the EGFR T790M mutation after receiving EGFR-TKI treatment.8,9 In March 2017, the U.S. Food and Drug Administration (FDA) approved Osimertinib as a first-line treatment for patients with metastatic NSCLC with EGFR mutation (deletion of exon 19 or mutation of exon 21 L858R), and obtained the permission of first-line treatment in China in August 2019.10,11