Oxaliplatin Added to Fluoropyrimidine/Bevacizumab as Initial Therapy for Unresectable Metastatic Colorectal Cancer in...

Doublet chemotherapy with fluoropyrimidine (FP) and oxaliplatin (OX) plus bevacizumab (BEV) is a standard regimen for unresectable metastatic colorectal cancer (MCRC). However, the efficacy of adding OX to FP plus BEV (FP + BEV) remains unclear for older patients, a population for whom FP + BEV is standard. We aimed to confirm the superiority of adding OX to FP + BEV for this population.

This open-label, randomized, phase III trial was conducted at 42 institutions in Japan. Patients with unresectable MCRC age 70-74 years with Eastern Cooperative Oncology Group performance status (ECOG-PS) 2 and those 75 years and older with ECOG-PS 0-2 were randomly assigned (1:1) to an FP + BEV arm or an OX addition (FP + BEV + OX) arm. Fluorouracil plus levofolinate calcium or capecitabine was declared before enrollment. The primary end point was progression-free survival (PFS). The study was registered in the Japan Registry of Clinical Trials (identifier: jRCTs031180145).

Between September 2012 and March 2019, 251 patients were randomly assigned to the FP + BEV arm (n = 125) and the FP + BEV + OX arm (n = 126). The median age was 80 and 79 years in the respective arm. The median PFS was 9.4 months (95% CI, 8.3 to 10.3) in the FP + BEV arm and 10.0 months (9.0 to 11.2) in the FP + BEV + OX arm (hazard ratio [HR], 0.84 [90.5% CI, 0.67 to 1.04]; one-sided P = .086). The median overall survival was 21.3 months (18.7 to 24.3) in the FP + BEV arm and 19.7 months (15.5 to 25.5) in the FP + BEV + OX arm (HR, 1.05 [0.81 to 1.37]). The proportion of any grade ≥3 adverse events was higher in the FP + BEV + OX arm (52% v 69%). There was one treatment-related death in the FP + BEV arm and three in the FP + BEV + OX arm.

No benefit of adding OX to FP + BEV as first-line treatment was demonstrated in older patients with MCRC. FP + BEV is recommended for this population.