Efficacy of antiepileptic drugs in adults vs children: Does one size fit all?

Comments on an article by J. M. Pellock et al. (see record [rid]2012-32888-015[/rid]). Pellock et al. report on a systematic review, funded by UCB Pharma, that was designed to address this question. An analysis of 30 clinical trials of adjunctive therapy for the treatment of partial-onset seizures allowed them to conclude that for this seizure type the efficacy of adjunctive antiepileptic therapy in adults is predictive of adjunctive antiepileptic therapy in children 2–18 years of age. The authors undertook a search of 3 databases (Medline/PubMed, Embase, and the Cochrane Library) for clinical antiepileptic efficacy trials (monotherapy and adjunctive therapy) of partial-onset seizures and primarily generalized tonic-clonic seizures in adult cohorts and children <2 years and 2–18 years; this yielded >3,000 hits, the vast majority of which were excluded based on stringent inclusion criteria set by the authors. The insufficient number of eligible trials did not permit an analysis of comparative efficacy in children <2 years, in monotherapy trials for the treatment of partial-onset seizures in children 2–18 years, and in any therapy in primarily generalized tonic-clonic seizures in children 2–18 years. Given this finding, the authors' conclusion is justified, as these trials were all superiority/inferiority studies with significant differences. However, based on limitations acknowledged by the authors, such as different trial designs and dosages, the conclusion drawn from their analysis should be viewed as qualitative, not quantitative, in the sense that one cannot exclude the possibility that any of the antiepileptic drugs could be less effective in children than in adults at any dose. Finally, the study by Pellock et al. addresses efficacy only. It is imperative to keep in mind that safety, adverse effects, and pharmacokinetics in children cannot be predicted from studies in adults. This article by Pellock et al. provides new and robust answers to an old and practically important question: Can efficacy data from antiepileptic drug trials in adults be extrapolated to children? The evidence presented indicates that this extrapolation is possible in the case of several antiepileptic drugs effective as adjunctive therapy against partial-onset seizures. The finding should provide some reassurance and support to all pediatric neurologists who, for decades, have had no other choice but to prescribe antiepileptic drugs off-label in order to do what they thought was best for their patients. However, given the limitations of this study and the available data, the answer to the question of whether one size fits all remains incomplete. Therefore, there is a continued need for randomized controlled studies in children to be performed either prior to initial marketing or soon thereafter. (PsycINFO Database Record (c) 2016 APA, all rights reserved)