A multicentre randomised trial comparing weekly paclitaxel + S-1 with weekly paclitaxel + 5-fluorouracil for patients with advanced gastric cancer.

Purpose: This study aimed to compare the efficacy and toxicity of weekly paclitaxel plus S-1 with weekly paclitaxel plus 5-fluorouracil in treating advanced gastric cancer as first line regimen. The primary end-point was disease control rate (DCR).

Methods: Patients with advanced or recurrent gastric cancer were randomly assigned to an experimental arm or a control arm. The experimental arm's dosage schedule was paclitaxel 60 mg/m2 (intravenous infusion) on days 1, 8 and 15 and S-1 80-120 mg/d (oral administration) on days 1-14. Control arm patients were given the same paclitaxel, combined with 5-fluorouracil 500 mg/m2 (continuous intravenous infusion) on days 1-5; and leucovorin 20 mg/m2 (intravenous infusion) on days 1-5. All schedules were repeated every 28 d.

Results: A total of 240 patients were enrolled and equally randomised into two arms. The overall response rate and DCR of the experimental arm was non-inferior to that of the control arm both in the per-protocol set and the full analysis set. The secondary end-point median progression-free survival (PFS) of the experimental and control arms was 153 and 129 d, with the hazard ratio of 0.641 (95% CI: 0.473-0.868, P = 0.004). The hazard ratio of the time to treatment failure of the two arms was 1.449 (95% CI: 0.705-2.980, P = 0.229). The six-month PFS rates of both arms were similar (31.3% versus 31.8%, P = 0.94). Cox regression analysis indicated that only treatment regimen and age were independent predictive factors for PFS. The most common adverse events were haematological and gastrointestinal. The rates of grade 3-4 adverse events were not significantly different between the two study arms and were mostly lower than 5%.

Conclusion: Weekly paclitaxel combined with S-1 is an active and well-tolerated regimen, supporting the view that S-1 can be an alternative for infusional 5-fluorouracil for advanced gastric cancer.