Content area
Full Text
Published online: 15 May 2018
© Springer International Publishing AG, part of Springer Nature 2018
Abstract
Background Dravet syndrome is a catastrophic form of pediatric treatment-resistant epilepsy with few effective treatment options. Stiripentol is approved for use in Canada for treatment of Dravet syndrome, but the associated longterm costs and benefits have not been well-studied and its cost effectiveness is unclear.
Objective The aim of this study was to evaluate the cost effectiveness of stiripentol as an adjunctive treatment to clobazam and valproate for treatment of Dravet syndrome from the perspective of the Canadian public healthcare payer.
Methods A cost-utility analysis was performed to estimate the costs and quality-adjusted life-years (QALYs) associated with adjunctive stiripentol treatment compared with clobazam and valproate alone in children with Dravet syndrome. Transition probabilities, drug efficacy, utility weights, and costs were obtained from a review of the literature. Probabilistic analyses were conducted using a Markov model with health states related to seizure frequency. A 10-year horizon was used. The incremental cost per QALY gained (incremental cost-effectiveness ratio [ICER]) for adjunctive use of stiripentol was calculated, and assumptions were explored in scenario analyses. All costs are expressed in 2017 Canadian dollars ($Can).
Results Compared with clobazam and valproate alone, the adjunctive use of stiripentol is associated with an ICER of $Can151,310. At a willingness-to-pay threshold of $Can50,000, the probability that stiripentol was the optimal treatment was 5.2%. The cost of stiripentol would need to be reduced by 61.4% for stiripentol to be cost effective.
Conclusion From the perspective of the Canadian public healthcare payer, stiripentol is not cost effective at its current price at a willingness-to-pay threshold of $Can50,000. Funding stiripentol will be associated with important opportunity costs that bear consideration.
1Introduction
Dravet syndrome is a rare form of catastrophic childhood epilepsy that accounts for slightly more than 1% of childhood epilepsies [1], with an estimated incidence of 1 in 15,700 [2]. Seizures typically begin before the age of 1 year, with developmental delays becoming apparent during the child?s second year [3]. Dravet syndrome is typically resistant to antiepileptic drugs, and polytherapy is often used in an attempt to control the multiple seizure types common to this syndrome [4]. Few clinical trials have evaluated the efficacy of antiepileptic drugs among...