Treatment of advanced Parkinson's disease in the United States: a cost-utility model.

Background: As Parkinson’s disease (PD) progresses, patients and their families experience substantial health and economic burdens. Because motor fluctuations (also called ‘off-time’) are linked to poor quality of life and higher healthcare costs, minimizing off-time is an effective strategy for reducing costs associated with PD. Objective: To assess the cost utility of rasagiline or entacapone as adjunctive therapies to levodopa versus levodopa/carbidopa/entacapone (LCE) versus standard levodopa monotherapy in patients with advanced PD and motor fluctuations in the US. Methods: A 2-year stochastic Markov model was utilized to examine the cost effectiveness of treatments of advanced PD. The model assumed that patients transition health status every 4 months. Transition probabilities, including uncertainties, were estimated from clinical trial data. Medical costs, daily drug costs and utility weights were obtained from published literature. Results: Over 2 years, all therapy options showed greater effectiveness than levodopa alone. Rasagiline + levodopa and LCE were cost saving from a payor perspective, while entacapone + levodopa was cost saving from a societal perspective. Mean benefits over 2 years were 0.12 (90% credibility interval [CI] 0.07, 0.18) additional quality-adjusted life-years (QALYs) for rasagiline + levodopa, entacapone + levodopa and LCE, 5.08 (90% CI 3.87, 6.28) additional months with ≤25% off-time for rasagiline + levodopa and 4.85 (90% CI 3.63, 6.06) additional months with ≤25% off-time for entacapone + levodopa and LCE versus levodopa alone. Conclusion: From a payor perspective, rasagiline + levodopa and LCE were dominant therapies over levodopa monotherapy, while entacapone+ levodopa was effective at a higher cost. With no additional cost over a 2-year period, rasagiline + levodopa presents a valuable alternative to entacapone + levodopa, LCE and levodopa monotherapy in the treatment of advanced PD patients. Results from this cost-utility model and prior adjunctive clinical data provide ongoing support for the adjunctive use of rasagiline in advanced PD patients with motor fluctuations.