JCO In a randomized, open-label, phase III NEJ009 study, gefitinib plus chemotherapy significantly improved progression-free survival (PFS) and overall survival (OS) compared with gefitinib-alone in patients with untreated non-small-cell lung cancer harboring mutations in epidermal growth factor receptor. Herein, we report the updated survival outcome and long-term tolerability. Patients were randomly assigned to gefitinib (gefitinib 250 mg orally, once daily) and gefitinib combined with carboplatin plus pemetrexed (GCP in a 3-week cycle for six cycles followed by concurrent gefitinib and pemetrexed maintenance) groups. At the data cutoff (May 22, 2020), GCP demonstrated significantly better PFS2 (hazard ratio, 0.77; 95% CI, 0.62 to 0.97; = .027) than gefitinib. However, the updated median OS was 38.5 months (95% CI, 31.1 to 47.1) and 49.0 months (95% CI, 41.8 to 56.7) in the gefitinib and GCP groups, respectively (hazard ratio, 0.82; 95% CI, 0.64 to 1.06; = .127). The OS in both groups was similar for the overall patient population. No severe adverse events occurred since the first report. This updated analysis revealed that the GCP regimen improved PFS and PFS2 with an acceptable safety profile compared with gefitinib-alone. GCP is more efficient than gefitinib monotherapy as a first-line treatment for non-small-cell lung cancer with epidermal growth factor receptor mutations.