Phase III randomized trial comparing 5-fluorouracil and oxaliplatin with or without docetaxel in first-line advanced gastric cancer chemotherapy (GASTFOX study)

Introduction In advanced gastric cancer, doublet regimen including platinum salts and fluoropyrimidine is considered as a standard first-line treatment. The addition of docetaxel (75 mg/m2 q3w) to cisplatin (75 mg/m2 q3w) and 5-fluorouracil has been shown to improve efficacy. However, this regimen (DCF) was associated with frequent severe toxicities (including more complicated neutropenia), limiting its use in clinical practice. Interesting alternative docetaxel-based regimens have been developed that need to be validated. Aim GASTFOX study is a randomized phase III trial comparing FOLFOX alone or with docetaxel at 50 mg/m2 (TFOX regimen) in first-line treatment for advanced gastric cancer. In both arms, cycle is repeated every 2 weeks until disease progression or unacceptable toxicity. Materials and methods Main eligibility criteria: histologically proven locally advanced or metastatic gastric or esogastric junction adenocarcinoma, HER negative status, measurable disease, ECOG performance status 0 or 1, and adequate renal, hepatic and bone marrow functions. Results The primary endpoint is radiological/clinical progression-free survival (PFS). A difference of 2 months for the median PFS in favor of TFOX is expected (HR = 0.73) Based on a two-sided α risk of 5% and a power of 90%, 454 events are required to show this difference. Secondary endpoints included overall survival, overall response rate, safety, quality of life and the therapeutic index. Conclusion This study is planned to include 506 patients to demonstrate the superiority of TFOX over FOLFOX in first-line advanced gastric cancer treatment (NCT03006432).