OBJECTIVES: A cost-minization analysis compared total costs of XELOX (capecitabine + oxaliplatin) versus FOLFOX-6 (5-FU + folinic acid + oxaliplatin) in the first line treatment for patients with metastatic colorectal cancer (mCRC) in Brazil. METHODS: METHODS: An analytic-decision model for projecting costs of treating mCRC in Brazil was developed considering local guidelines and the Brazilian payers’ perspective. According to the phase III trial of Ducreux et al 2007, we assumed the same efficacy for XELOX and FOLFOX-6 in terms of progression free-survival and overall survival. Only direct costs (drugs, IV administration, physician fees, materials, etc.) were considered for the chemotherapy and for treating adverse events. The time-horizon of this analysis was 126 days according to the mean number of Progression Free Survival found in the Ducreux clinical trial (6 cycles of XELOX and 9 cycles of FOLFOX-6). For the base case a patient with 1.7 m² was considered. A Delphi panel was conducted to identify local practices to manage the adverse events of each scheme. Discount rate was not necessary because of the short length of the analysis. RESULTS: RESULTS: Drug acquisition costs for FOLFOX-6 were higher than XELOX (R$66,433 vs. R$59,657). XELOX treatment generated a R$15,465 saving per patient due to a 92% reduction in the number of IV administrations. XELOX also presented a reduction of R$2,121.65 in costs related to the management of adverse events. A one-way sensitivity analysis was conducted and confirmed the robustness of the results. CONCLUSIONS: Findings suggest XELOX as a cost-saving therapy for the first line treatment for mCRC under the payer perspective in Brazil when compared to FOLFOX-6. when compared to FOLFOX-6.