Phase II study of biweekly docetaxel and S-1 combination therapy for advanced or recurrent gastric cancer

Objective: This phase II study evaluated the toxicity and efficacy of a novel dosing schedule of docetaxel and S-1 as treatment for advanced gastric cancer. Methods: Patients with measurable advanced or recurrent gastric cancer and no prior exposure to the investigational drugs were treated with intravenous docetaxel 35 mg/m² on days 1 and 15, and oral S-1 80 mg/m ²/day on days 1-14 every 4 weeks. The primary endpoint was objective response. Results: Thirty-five eligible patients were enrolled and received a total of 151 cycles of treatment (median 3, range 1-19). One complete response and 13 partial responses were observed, with an overall response rate of 40% (95% CI: 24-56%). Median progression-free survival and median overall survival times were 4.5 and 14.2 months, respectively. The most common grade 3-4 toxicities were neutropenia (23%) and leukocytopenia (15%). Conclusion: Biweekly docetaxel combined with S-1 is active in advanced or recurrent gastric cancer, and can be administered with proper management of adverse events in an outpatient clinic.