A cost-utility analysis of thrombopoietin receptor agonists for treating pediatric immune thrombocytopenia purpura after failure of first-line therapies.

Abstract

Thrombopoietin receptor agonists (TPO-RAs) have emerged as a recommended treatment for children with persistent and/or chronic immune thrombocytopenic purpura (ITP). The purpose of this study was to evaluate the cost-effectiveness of TPO-RAs relative to treatment without TPO-RAs (non-TPO-RAs/usual care) for ITP in children who do not respond to first-line therapy and in whom splenectomy is not recommended in Ontario, Canada, from a hospital payer perspective. A 2-year Markov model with an embedded decision tree was used. Data on medications used, dose, response rate, bleeding, and emergency treatment events were collected from the Hospital for Sick Children in Toronto. The health outcomes were described in quality-adjusted life-years (QALYs). Health-state utilities were derived from the peer-reviewed literature. Scenario analyses, deterministic, and probabilistic sensitivity analyses were conducted. Economic costs were measured in 2021 Canadian dollars ($1.00=US$0.80) RESULTS: TPO-RAs are estimated to result in an increased cost of $27,118 and a QALY gain of 0.21 compared to non-TPO-RAs over a 2-year horizon, resulting in an incremental cost-effectiveness ratio (ICER) of $129,133. In a 5-year scenario analysis, the ICER fell to $76,403. In the probabilistic sensitivity analysis, TPO-RAs exhibit a 40.0% probability of being cost-effective at a conventional ($100,000) willingness-to-pay threshold per QALY gained. Further assessment of the long-term efficacy of TPO-RAs is warranted to obtain more precise long-term estimates. As the costs of TPO-RAs decline with the introduction of generic formulations, TPO-RAs may be increasingly cost-effective.