Cost-Utility of Treatments for Pulmonary Arterial Hypertension A Markov State-Transition Decision Analysis Model Margaret C. Garin, 1 Leslie Clark, 2 Elinor C.G. Chumney, 3 Kit N. Simpson 4 and Kristin B. Highland 5 1 Department of Medicine, Hospital of the University of Pennsylvania, Philadelphia, Pennsylvania, USA 2 Department of Biostatistics, Bioinformatics, and Epidemiology, Medical University of South Carolina, Charleston, South Carolina, USA 3 School of Pharmacy, Belmont University, Nashville, Tennessee, USA 4 Department of Health Administration and Policy, College of Health Professions, Medical University of South Carolina, Charleston, South Carolina, USA 5 Division of Pulmonary, Critical Care, Allergy and Sleep Medicine and Division of Rheumatology and Immunology, Medical University of South Carolina, Charleston, South Carolina, USA Abstract Background and Objective: Clinicians must choose between an increasing num- ber of medications for the treatment of pulmonary arterial hypertension (PAH) with different routes of administration, adverse effects, costs and efficacies. We constructed a decision analysis to help inform treatment choices in PAH. Methods: We created a Markov-type model to evaluate 1-year treatment with bosentan, treprostinil, epoprostenol, inhaled iloprost, sildenafil, sitaxentan and ambrisentan. Transition probabilities were based on observed transitions between WHO functional classes, adjusted by relative risk of improvement in a 6-minute walk test. Utilities were based on reported values for each func- tional class, adjusted for burden of treatment administration. Costs were estimated from Medicare and Medicaid reimbursement data. Sensitivity analyses evaluated changes in efficacy, utilities and costs. Results: Treatment with sildenafil was less costly and resulted in a greater gain in quality-adjusted life-years (QALYs) compared with other treatments. Treat- ment with ambrisentan and bosentan resulted in the same gain in QALYs as sildenafil, but at a higher cost. Sensitivity analyses had minimal impact on these results. Conclusions: Based on this model, sildenafil is a cost-effective treatment for PAH with a low price and a net increase in QALYs. The results from this analysis are a tool to help guide clinicians in deciding which PAH medications to use; however, the final decisions should be individualized because the ef- fectiveness of therapy, resulting utilities and acceptable costs will differ with each patient. ORIGINAL RESEARCH ARTICLE Clin Drug Investig 2009; 29 (10): 635-646 1173-2563/09/0010-0635/$49.95/0 ª 2009 Adis Data Information BV. All rights reserved.