Phase I/II study of a combination of S-1 and weekly paclitaxel in patients with advanced or recurrent gastric cancer

Objective: A phase I/II study of a combination of S-1 and weekly paclitaxel was conducted to determine the maximum tolerated dose (MTD), recommended dose (RD), dose-limiting toxicities (DLTs) and objective response rate (RR) in patients with advanced or recurrent gastric cancer. Methods: S-1 was administered orally at a fixed dose of 80 mg/m(2) per day on days 1-14. Paclitaxel was injected intravenously on days 1, 8, and 15, starting with a dose of 50 mg/m(2). The dose was increased in a stepwise manner. Results: In phase I, level 2 (60 mg/m(2)) was considered the MTD, because 2 of 3 patients in level 2 developed DLTs (grade 3 neutropenia and anemia, and grade 4 diarrhea and stomatitis). Therefore, the RD was determined to be level 1 (50 mg/m(2)). In phase II, efficacy and safety were assessed in 18 patients treated with the RD. The RR was 64.7% and the median survival time was 13.5 months. The most severe toxicities were grade 3 leukopenia (5.5%) and grade 3 neutropenia (5.5%). Conclusion: Our study showed that S-1 combined with 50 mg/m(2) paclitaxel is effective and safe in patients with advanced or recurrent gastric cancer. Copyright (C) 2008 S. Karger AG, Basel.