Phase 2 study of S-1 plus carboplatin in patients with advanced non-small cell lung cancer

We conducted a phase II study of S-1 and carboplatin combination regimen in the treatment of patients with advanced non-small cell lung cancer (NSCLC). Chemotherapy-naïve patients with advanced NSCLC were treated with S-1 and carboplatin. S-1 was administered orally twice daily for 14 days and carboplatin AUC 5 on day 1 of each cycle, and this was repeated every 4 weeks.Twenty-nine patients were enrolled in this study. The main grade 3 or 4 toxicities observed during the first cycle were neutropenia (10.3%), thrombocytopenia (41%), and transaminase elevation. Objective responses were seen in 9 patients (response rate 31.0%). The median survival time and median progression-free survival were 16.0 months (95% CI, 12.1–19.0 months) and 4.5 months (95% CI, 3.2–6.1 months), respectively. Hematological adverse events reaching grade 3 or 4 were neutropenia (10.3%), anemia (3.4%), and thrombocytopenia (3.4%). No febrile neutropenia was detected. Nonhematological toxicities were also mild. Although grade 3 infection was observed in 1 patient, the patient improved without intervention. The combination of S-1 plus carboplatin is an active and well-tolerated regimen for the treatment of patients with advanced NSCLC. Further investigations are required to confirm our results in randomized trials.