Pharmacoeconomic Analysis of the Use of Thrombopoietin Receptors Agonists in Idiopathic Thrombocytopenic Purpura Therapy

Abstract

Background. New medications, thrombopoietin mimetics which were recently introduced into clinical practice allowed to achieve clinical response in patients with chronic glucocorticoid-resistant idiopathic thrombocytopenic purpura (ITP). However, the high cost and the need for long-term administration necessitate a pharmacoeconomic analysis of the use of thrombopoietin receptors agonists in the treatment of ITP. Aim. To assess the cost-effectiveness of the use of thrombopoietin mimetics (romiplostim and eltrombopag) and immunosuppressive therapy in the treatment of chronic glucocorticoid-resistant ITP. Materials & Methods. The Markov modelling of diagnosis and treatment of ITP was conducted in accordance with the National guidelines for diagnosis and treatment of primary ITP. The cost-benefit analysis of the use of thrombopoietin receptors agonists (romiplostim and eltrombopag) and immunosuppressive therapy was performed. The time period (horizon) of the study was 5 years. Results. The therapy with thrombopoietin mimetics had higher costs but was shown to be more effective compared to immunosuppressive therapy. The cost-effectiveness for achieving 1 QALY in the treatment was 1.33 million rubles with eltrombopag, 4.2 million rubles with romiplostim, and 0.17 million rubles with immunosuppressive therapy. The lowest additional costs compared to immunosuppressive therapy had eltrombopag treatment, whereas romiplostim treatment doubled the additional costs. The threshold values of the ratio of thrombopoietin receptors agonists costs were determined for the cost-benefit analysis. The use of romiplostim is cost-effective at a price for 1 vial of 15-18 % less than for 1 package of eltrombopag. The total cumulative burden of treatment of chronic ITP for 5 years may be 7.18 billion rubles with the use of eltrombopag, 23.23 billion rubles with romiplostim, and 0.91 billion rubles with immunosuppressive therapy only. The results confirm the need for budgeting the diagnosis and treatment of ITP not as a part of general approach, but to consider ITP as an orphan disease. Conclusion. The developed pharmacoeconomic model can be used as an assessment tool of the costs of new diagnostic approaches and treatment strategies and optimizing budget expenditures.