Phase I/II study of S-1 combined with biweekly irinotecan chemotherapy in previously treated advanced non-small cell lung cancer.

Purpose: This phase I/II study was designed to evaluate a combination of irinotecan and S-1 a new regimen for salvage chemotherapy in patients with advanced or metastatic non-small cell lung cancer (NSCLC).

Methods: The study group comprised patients with advanced or metastatic NSCLC who had previously received at least one platinum-containing chemotherapy. Patients received irinotecan on days 1, 15 and oral S-1 (40 mg/m(2) twice daily as a fixed dose) on day 1 to 14 of a 28-day cycle.

Results: In the phase I part, irinotecan was given in escalating doses of 70 (Level 1), 80 (Level 2), and 90 mg/m(2) (Level 3). Three of the 5 patients given Level 3 had dose-limiting toxicity, and Level 2 (80 mg/m(2) of irinotecan) was designated as the recommended dose. In phase II, 38 patients received a median of 7.4 cycles of irinotecan at the recommended dose. The overall response rate was 15.8 % (90 % confidence interval (CI): 6.1-25.5 %), and the median progression-free and overall survival times were 4.5 months (95 % CI: 3.5-5.0) and 15.0 months (95 % CI: 9.5-20.6) months, respectively. Toxicity was generally mild. Grade 3 or higher toxicity included neutropenia in 17.9 % of the patients, thrombocytopenia in 5.1 % and nausea in 7.7 %.

Conclusion: Combination chemotherapy with S-1 and irinotecan was considered an effective salvage regimen in patients with advanced or metastatic NSCLC.