Update on third-generation EGFR tyrosine kinase inhibitors

Among patients with non-small cell lung cancer (NSCLC), EGFR mutations, 90% of which present as an exon 19 deletion or exon 21 point mutation L858R, have been detected in Western and Asian populations at a rate of ~15% and ~40%, respectively. To date, numerous trials have established the efficacy and toxicity profile of singleagent oral EGFR-tyrosine kinase inhibitor (TKI) therapies for EGFR-TKI-naïve NSCLC patients harboring EGFR mutations. These trials include IPASS for gefitinib (1), Optimal for erlotinib (2), and LUX-Lung 3 for afatinib (3). Still, the majority of patients will eventually develop resistance.