The cost effectiveness of newer epilepsy treatments: a review of the literature on partial-onset seizures.

BACKGROUND AND
OBJECTIVE: Epilepsy is one of the most common neurological disorders, affecting more than 3 million people in Europe. This paper reviews the published evidence regarding the cost effectiveness of second-generation antiepileptic drugs (AEDs).
METHODS: A systematic literature search was performed, using the databases Academic Search Complete, Econlit, EMBASE and MEDLINE. Health economic evaluations of newer (second-generation) AEDs, published as full-length journal articles, were searched for. We focused on evaluations of newer AEDs as treatment for partial-onset seizures. 470 studies were initially identified and 19 were finally included. Information regarding (i) AEDs studied, (ii) cost effectiveness, and (iii) a variety of health economic modelling specifics was extracted from each study. Then, the included studies were summarized and a quality assessment was performed, according to the British Medical Journal's guidelines for economic studies.
RESULTS: The results were as follows: (i) the cost per additional QALY for newer AEDs used as adjunctive treatment, compared with standard therapy, ranged between $US19 139 (levetiracetam) and $US57 210 (pregabalin) [year 2010 values]; no cost-effectiveness evidence was identified for felbamate, eslicarbazepine, oxcarbazepine or tiagabine; and (ii) all studies met at least 60% of the British Medical Journal's guidelines criteria, and seven studies were found to satisfy more than 80% of the criteria. Guidelines criteria not met involve inadequate reporting of input data and modelling details, including validation and availability of models used for cost-effectiveness calculations.
CONCLUSIONS: Although failure to meet good practice guidelines influences the reliability of the presented evidence adversely, a sufficient number of the included studies were found to comply enough with the guidelines in order for the qualitative content of the cost-effectiveness results - that some of the newer AEDs are cost effective - to be reliable. In fact, this conclusion is likely to be relatively robust, since the effect of improved seizure control on labour market performance was not included in the base-case results in any of the included studies and improved seizure control need only to have a moderate effect on sickness absenteeism in order for the corresponding treatment to be cost effective even when willingness to pay for an additional QALY is low. However, the cost effectiveness of newer AEDs has only been studied for a small number of settings, and hence future studies incorporating additional settings are needed.