ADJUNCTIVE LAMOTRIGINE THERAPY IN PATIENTS WITH REFRACTORY SEIZURES -A LIFETIME COST-UTILITY ANALYSIS

Objective: Lamotrigine as add-on treatment (500 mg per day) is effecti ve in patients with refractory epilepsy, but its high cost requires a pharmacoeconomic analysis. We conducted a retrospective lifetime cost- utility study in which clinical data were derived from a recent placeb o-controlled clinical trial, cost-of-illness data were drawn from a pr evious ad-hoc study, and quality-of-life values were obtained by prosp ectively interviewing a separate group of 81 patients referred to our institution with epilepsy. Results. Our analysis showed that chronic l amotrigine treatment implies an incremental lifetime cost of about $1 600 000 for every 100 patients. Incremental lifetime utility was aroun d 40 quality-adjusted life-years (QALYs) for every 100 patients. On th e basis of these data, adjunctive lamotrigine was estimated to cost ap proximately $41 000 per QALY gained. Sensitivity testing suggested a r ange of $25 000-$85 000 per QALY gained. Conclusion: Adjunctive lamotr igine (500 mg per day) in refractory epilepsy seems to have a worse ph armacoeconomic profile than many pharmacological treatments commonly u sed in areas other than epilepsy. Further data are needed to determine if lamotrigine can be equally effective at lower (and less costly) da ily doses which could markedly improve its pharmacoeconomic characteri stics.