EGFR and non-small cell lung carcinoma: As a substrate of the permeability glycoprotein, osimertinib has shown greater penetration of the blood-brain barrier than gefitinib, rociletinib, or afatinib, and it is also more widely distributed in the primary brain, which accounts for the satisfying outcomes observed to date in brain-metastatic EGFR-mutant NSCLC patients [18].