A Monoclonal Antibody Against HER-2 (trastuzumab) for Metastatic Breast Cancer: a Model-based Cost-effectiveness Analysis

Background: The aim of this study was to evaluate the cost-effectiveness of trastuzumab in patients with metastatic breast cancer (MBC) in a model-based cost-effectiveness analysis (CEA). Trastuzumab has shown considerable activity in patients with MBC that overexpress HER2. However, significant resources have been allocated to finance this new therapy. Due to ever increasing pressures on health care budgets, economic evaluations are requested in order to compare health effects with costs.

Methods: All available data on trastuzumab in MBC presented at the San Antonio breast cancer conference in late 2003 and all data on Medline in December 2003 were analysed for life years (LY) gained and quality of life (QoL) with regard to the use of this new monoclonal antibody. Randomised studies comparing standard chemotherapy, with or without trastuzumab, were focused. The costs were calculated according to Norwegian prices as of January 2003.

Results: The LY gained ranged between 0.3 and 0.7 years. The median cost per patient treated was 44 196 yielding costs per life year saved in the range 63 137-162 417 depending on survival gain and discount rate employed. A sensitivity analysis documented the price of trastuzumab and the survival benefit the two major factors influencing the cost-effectiveness ratio.

Conclusion: The economic evaluation indicates that trastuzumab is not cost effective in metastatic breast cancer. Reduced drug costs and/or improved survival may alter the conclusion.