RCT: Osimertinib Significantly Extends Progression-Free Survival in Unresectable Stage III EGFR-Mutated NSCLC After Chemoradiotherapy – N Engl J Med

Study Design and Population: This phase 3, double-blind, placebo-controlled trial enrolled 216 patients with unresectable stage III EGFR-mutated non-small-cell lung cancer (NSCLC) who showed no disease progression during or after chemoradiotherapy. Patients were randomly assigned to receive either osimertinib (143 patients) or a placebo (73 patients) until disease progression.

Main Findings: The study found that osimertinib significantly prolonged progression-free survival (PFS) compared to placebo, with a median PFS of 39.1 months versus 5.6 months, respectively. The hazard ratio for disease progression or death was 0.16, indicating a substantial reduction in risk with osimertinib. At 12 months, 74% of patients in the osimertinib group were alive and progression-free, compared to 22% in the placebo group. Interim overall survival data suggested a modest difference favoring osimertinib, though it was not statistically significant.

Implications for Practice: Osimertinib offers a significant survival benefit as a consolidation therapy following chemoradiotherapy in patients with unresectable stage III EGFR-mutated NSCLC. The findings support the use of osimertinib in this setting, despite an increased incidence of adverse events, highlighting its role in improving long-term outcomes.

Reference: Lu, S., Kato, T., Dong, X., Ahn, M.J., Quang, L.V., Soparattanapaisarn, N., Inoue, T., et al. (2024). Osimertinib after chemoradiotherapy in stage III EGFR-mutated NSCLC. New England Journal of Medicine, 391(7), 585-597. DOI: 10.1056/NEJMoa2402614.