Imatinib as a Dominant Therapeutic Strategy in the Treatment of Chronic Myelogenous Leukemia: A Decision-Analytic Approach

Abstract

Objective: To develop and populate a decision-analytic model comparing the cost and efficacy of imatinib versus allogenic bone marrow transplantation (BMT) with a matched unrelated donor in the treatment of newly-diagnosed, Philadelphia positive (Ph (+)), chronic phase, chronic myelogenous leukemia (CML). Design: Markov cohort analysis and Monte Carlo microsimulation. Measurements and Main Results: Direct medical costs were measured from the perspective of a third-party payer. Efficacy data and probabilities were obtained from survivability findings emanating primarily from randomized controlled trials (RCTs). A two-year time horizon was employed with three month treatment cycles. BMT was established as the baseline comparator and the base case was defined as a 35 year old, Ph(+) male patient with newly-diagnosed CML. Results from the Monte Carlo trial found that the incremental cost-efficacy ratio was −$5,000 for imatinib (95th % Confidence Interval: −$70,000, $84,000). Analysis of the cost-efficacy plane indicated that imatinib dominated BMT in 84.69 percent of cases, while BMT was dominant in 0.76 percent of cases. Sensitivity analyses of costs and discount rates found results to be robust. Conclusion: Imatinib was observed in a majority of cases to be both less costly and more efficacious relative to BMT in the treatment of CML, suggesting that this pharmaceutical agent is a dominant therapeutic strategy. When available, the incorporation of long-term clinical data are required to assess cost-efficacy beyond the two-year time horizon of this study.