Trastuzumab in adjuvant breast cancer therapy: A model based cost-effectiveness analysis.

628 Background: Trastuzumab has shown activity in patients with early breast cancer that overexpress HER2. However, significant resources have to be allocated to finance this therapy, therefore its cost-effectiveness is called for and treatment's value for money should be calculated. We aimed to evaluate the marginal cost effectiveness of trastuzumab in adjuvant treatment of HER2 positive early breast cancer in a model based cost-effectiveness-analysis (CEA). METHODS A breast cancer treatment model was set up. Societal costs were calculated according to Norwegian prices as in September 2005 and converted to Euros at the rate of 1Euro = 7.81 NOK. Life expectancy data were based on the literature and prolonged according to qualified guess (10% and 20% improved overall survival (OS). The comparator was the present practice, the FEC100 regimen alone. The human capital approach was employed and a sensitivity analysis was added. RESULTS The median raised cost per patient treated was calculated at Euro16,713 - 35,714. The yielding cost per life year saved was in the range between Euro 5,571 and 32,616, depending on survival gain (10% or 20% improved OS) and discount rate (0% or 3%) employed. The sensitivity analyses documented survival gain, discount rate and price of trastuzumab the major factors influencing cost-effectiveness ratio. CONCLUSION The economic evaluation indicates trastuzumab cost effective in adjuvant breast cancer treatment. No significant financial relationships to disclose.