PURPOSE: New therapies for pulmonary arterial hypertension (PAH) improve functional status, quality of life, and survival. Clinicians must now choose between an increasing number of medications with different routes of administration, adverse effects, costs, and effects on outcomes of interest. We constructed a decision analysis to help inform these treatment choices.
METHODS: We created a Markov-type model to evaluate the expected outcomes and costs of 1-year treatment with bosentan, treprostinil, epoprostenol, inhaled iloprost, sildenafil, sitaxsentan, and ambrisentan. Transition probabilities were based on observed transitions between World Health Organization functional classes for bosentan. Treatment effects of the other treatments were adjusted by relative risk of improvement in six-minute walk test for each drug. Utilities were based on reported values for each functional class, adjusted for treatment burden associated with intravenous, subcutaneous, and inhaled administration. Costs were estimated from Medicare reimbursement data. Sensitivity analyses included effects of changes in treatment outcome, utilities, and costs.
RESULTS: Treatment with sildenafil compared to that with other treatments was less costly and resulted in a greater gain in quality-adjusted life years (QALYs) except when compared to ambrisentan, in which treatment with ambrisentan resulted in a greater gain of QALYs at a cost of $40,516,122 per QALY. Treatment with iloprost was more expensive with less gain in QALYs compared to other treatments, except when compared to treprostinil or epoprostenol, in which treatment with iloprost resulted in a larger gain in QALYs at costs of $1,382,439 and $1,213,941 per QALY, respectively. Sensitivity analyses had minimal impact on these results.
CONCLUSION: Treatment with sildenafil is the most cost-effective treatment for PAH. Sildenafil is less expensive that other treatments and results in a net improvement in quality-adjusted survival.
CLINICAL IMPLICATIONS: The results from this analysis are a tool to help guide clinicians in deciding which PAH medications to use in treating their patients. This process must take into account the life-style of the patient in question because utilities and acceptable costs will differ between patients.
DISCLOSURE: Margaret Garin, Grant monies (from industry related sources) Actelion Pharmaceuticals, Encysive Pharmaceuticals, Gilead Sciences, United Therapeutics; Consultant fee, speaker bureau, advisory committee, etc. Actelion Pharmaceuticals, Encysive Pharmaceuticals, Gilead Sciences, United Therapeutics; Product/procedure/technique that is considered research and is NOT yet approved for any purpose. Sitaxsetan and ambrisentan are not FDA approved treatments for pulmonary arterial hypertension.