Goals of work: An economic evaluation was conducted comparing anastrozole, exemestane, letrozole and megestrol for the second-line treatment of postmenopausal patients with hormone-sensitive metastatic breast cancer who had failed tamoxifen.
Methods: An economic model was developed based on data from phase III megestrol-controlled clinical trials of antiaromatase agents (AA) and estimates of resource utilization from both Statistic Canada's Population Health Model for breast cancer and expert opinion.
Main results: In megestrol-controlled trials, anastrozole and exemestane equivalently improved survival compared to megestrol, while letrozole did not. Compared to megestrol, exemestane and anastrozole both cost Canadian $9000 per life-year gained, and letrozole saved Canadian $300 annually, with no life-year gain. Cost-effectiveness results were robust under sensitivity analysis testing. However, the model was dependent on any difference between AAs with respect to survival benefit and drug acquisition price.
Conclusion: Based on available data and this cost-effectiveness analysis, exemestane and anastrozole are appropriate choices for second-line hormonal treatment of metastatic breast cancer.