P-0246 Cost-Effectiveness of Cetuximab Versus Panitumumab in Third-Line Therapy for Chemotherapy-Refractory Metastatic Colorectal Cancer in Brazil

Abstract

ABSTRACT Introduction Cetuximab and panitumumab are monoclonal antibodies against epidermal growth factor receptor (EGFR), with different efficacy and toxicity profiles. Both drugs could improve survival in patients with colorectal cancer in whom other treatments have failed. The objective of this analysis, from the Brazilian public health system perspective, was to evaluate the cost-effectiveness of monotherapy with cetuximab versus panitumumab in third-line treatment of mCRC. Methods A Markov model was developed to simulate chemotherapy-refractory mCRC patient outcomes and costs throughout third-line treatment, comparing cetuximab vs panitumumab. All patients were supposed to have KRAS wild-type tumors, and had been previously treated with a fluoropyrimidine, irinotecan, and oxaliplatin. Data for model parameters were derived from randomized studies projecting outcomes for a lifetime period. Resource use included drugs, physician visits, scans, laboratory exams, hospitalizations, and treatment of adverse events. The associated costs were obtained from price tables regulated by Brazilian Ministry of Health and are expressed in US dollars. The incremental cost per life-year gained was calculated comparing both strategies to best supportive care (BSC) alone. Download : Download full-size image Results The use of cetuximab and panitumumab to chemotherapy-refractory mCRC patient resulted in 0.30 and 0.03 additional life-years, respectively, with incremental cost effectiveness ratios (ICERs) of $101,509 and $511,771 per LY, respectively, relative to BSC. The use of cetuximab was dominant over panitumumab. The ICERs are mainly driven by the risk of death or progression during treatment and the acquisition cost of biological agents. Conclusion The economic evaluation demonstrates that both cetuximab and panitumumab are not a cost-effective approach in wtKRAS mCRC patients. However, the use of cetuximab was dominant over panitumumab, showing that monotherapy with cetuximab could be the preferred choice as salvage therapy in this population.