Whole Genomic Landscape of Advanced EGFR-mutant NSCLC

This open-label, single-arm, non-randomized phase 2 exploratory study has been designed to evaluate the mechanisms of resistance to first-line osimertinib 80mg once daily in NSCLC patients with EGFR-activating mutation who were naïve to chemotherapy as well as EGFR TKIs. Acquired resistance to first-line osimertinib is mediated by heterogeneous mechanisms including MET amplification (15%), secondary EGFR mutation including C797S or S768I (7%), PIK3CA mutation (7%), CDK4/6 amplification (5%), KRAS mutation (3%), BRAF mutation (3%), CCND1-3 amplification (3%), CCNE1 amplification (2%), HER2 amplification (2%), and SPTBN1-ALK fusion (1%) using plasma genotyping of FLAURA study (N=91). Therefore, this study is necessary to evaluate resistance mechanisms of ≥1% to first-line osimertinib in NSCLC patients with EGFR-activating mutations using whole-genomic profiling of tumours at pre-treatment and progression which acquisitions are mandatory.