Cost effectiveness of lacosamide in the adjunctive treatment of patients with refractory focal epilepsy in Belgium. 
Lacosamide is an anti-epileptic drug, indicated as adjunctive therapy for patients with focal seizures with or without secondary generalization.  This study aims to assess the cost effectiveness of standard anti-epileptic drug therapy plus lacosamide 300 mg/day compared with standard therapy alone from the perspective of the Belgian healthcare payer.  The treatment pathway of a hypothetical cohort of 1000 patients over 2 years was simulated using a decision tree.  Data about health state probabilities, seizure frequency and utility values were taken from lacosamide trials or from the literature.  Effectiveness measures included the number of seizures avoided and the number of quality-adjusted life-years gained.  Unit costs were taken from national references.  Resource use was estimated by a panel of eight neurologists with extensive experience in epilepsy.  The price year was 2008.  Deterministic and probabilistic sensitivity analyses were conducted.  Over a 24-month period, standard anti-epileptic drug therapy plus lacosamide led to a reduction of seven seizures, an increase of 0.038 quality-adjusted life-years and a cost decrease of &U20AC;3619 per patient compared with standard therapy alone.  Using a willingness to pay of &U20AC;30 000 per quality-adjusted life-year, the net monetary benefit of standard anti-epileptic drug therapy plus lacosamide amounted to &U20AC;4754.  The probability of standard anti-epileptic drug therapy plus lacosamide being cost effective was 97.3%, 99.8%, 99.9% and 100% at 6, 12 , 18 and 24 months, respectively.  In patients with difficult-to-treat epilepsy, standard anti-epileptic drug therapy plus lacosamide appears to be a cost-effective option in Belgium.