Abstract
BACKGROUND: The FLAURA study was a multicenter, double-blind, Phase 3 study in which patients with previously untreated epidermal growth factor receptor mutation-positive advanced non-small-cell lung carcinoma were randomized 1:1 to oral osimertinib 80 mg once daily or standard-of-care (gefitinib 250 mg or erlotinib 150 mg, once daily) to compare safety and efficacy. In the overall FLAURA study, significantly better progression-free survival was shown with osimertinib versus standard-of-care. METHODS: Selected endpoints, including progression-free survival (primary endpoint), overall survival, objective response rate, duration of response and safety were evaluated for the Japanese subset of the FLAURA study. RESULTS: In Japan, 120 eligible Japanese patients were randomized to osimertinib (65 patients) or gefitinib (55 patients) treatment from December 2014 to June 2017. Median progression-free survival was 19.1 (95% confidence interval, 12.6, 23.5) and 13.8 (95% confidence interval, 8.3, 16.6) months with osimertinib and gefitinib, respectively (hazard ratio, 0.61; 95% confidence interval, 0.38, 0.99). Median overall survival was not reached in either treatment arm (data were immature). In the osimertinib and gefitinib arms, objective response rate was 75.4% (49/65) and 76.4% (42/55), and median duration of response from onset was 18.4 (95% confidence interval, not calculated) and 9.5 (95% confidence interval, 6.2, 13.9) months, respectively. The incidence of adverse events was similar in the two groups. The frequency of Grade ≥3 interstitial lung disease and pneumonitis in the two groups were the same (one patient). CONCLUSIONS: As the first-line therapy, osimertinib showed significantly improved efficacy versus gefitinib in the Japanese population of the FLAURA study. No new safety concerns were raised. CLINICAL TRIAL REGISTRATION: NCT02296125 (ClinicalTrials.gov).