Phase II Study of the EGFR-TKI Rechallenge With Afatinib in Patients With Advanced NSCLC Harboring Sensitive EGFR Mutation Without T790M: Okayama Lung Cancer Study Group Trial OLCSG 1403

Abstract Epidermal growth factor receptor (EGFR) tyrosine kinase inhibitors (TKIs) as first-line therapy for patients with EGFR-mutated non–small-cell lung cancer (NSCLC) have shown a significantly better objective response rate and progression-free survival than platinum doublet therapy. However, acquired resistance often occurs within 12 months. One of the potential strategies for treating acquired resistance in NSCLC is the readministration of EGFR-TKIs, a strategy that has mainly been evaluated using gefitinib or erlotinib. The aim of the present study is to investigate the efficacy and safety of EGFR-TKI readministration with afatinib in patients with advanced NSCLC harboring activating EGFR mutations without T790M. The primary endpoint is progression-free survival. The secondary endpoints include the objective response rate, disease control rate, overall survival, toxicity, and quality of life. A total of 12 patients will be enrolled in this trial.