Cost-Effectiveness Analysis of Rituximab for Chronic Lymphocytic Leukemia Using A Semi-Markovian Model Approach in R

Objectives: This study aims to compare the strategies fludarabine, cyclophosphamide, and rituximab and fludarabine and cyclophosphamide for the treatment of chronic lymphocytic leukemia in Brazil.Methods: A three-states clock-reset semi-Markovian model was constructed in R. The time horizon of the analysis was 15 years and monthly cycles were used. Transition probabilities were derived from the survival curves of the CLL-8 study. Other probabilities were also derived from the medical literature. Costs included in the model referred to the application of injectable drugs, prescription cost, cost of treating adverse events, and costs of supportive care. The model was evaluated by microsimulation. To determine the study result, multiple cost-effectiveness threshold values were used.Results: In the main analysis, an incremental cost-effectiveness ratio of 19029.38 PPP-US dollars (USD)/quality-adjusted life -year (QALY) (41141.52 Brazilian real/QALY) was observed. In 1.8% of the iterations, fludarabine and cyclophosphamide was considered dominant over fludarabine, cyclophosphamide, and rituximab. It can be shown that at 1 gross domestic product (GDP) per capita/QALY, 36.1% of the iterations would consider the technology cost-effective. At 2 GDP per capita/ QALY, this number rises to 82.1%. At 50 000 USD/QALY, 92.8% of the iterations would suggest the technology to be cost-effective. In terms of some threshold accepted or proposed around the world, the technology would be considered cost-effective at 50 000 USD/QALY, 3 GDP per capita/QALY, and 2 GDP per capita/QALY. It would not be cost-effective at 1 GDP per capita/QALY or the opportunity costs threshold.Conclusion: It can be considered that rituximab is cost-effective for the treatment of chronic lymphocytic leukemia in Brazil.