Purpose: To review the current state of knowledge of the treatment of primary (idiopathic) generalized epilepsy syndromes based on the efficacy results of clinical trials, to highlight obstacles in the design of these trials, and to suggest solutions for future research.
Methods: Published reports of controlled clinical trials, as well as large or significant uncontrolled trials of treatments for these syndromes, were reviewed. Trials were selected for discussion based on their importance or their illustration of design issues.
Results: Only a few randomized, controlled trials of therapy for these syndromes exist. Conclusions based on this Class I data include efficacy in absence epilepsies for ethosuximide, valproate, and lamotrigine, and for eight drugs for primary generalized tonic-clonic seizures. Many commonly accepted therapeutic strategies are not based on formal data. No controlled data exist for uncommon syndromes.
Conclusions: More clinical trials of therapies for primary generalized epilepsies are needed. To overcome design obstacles, better funding, multicenter cooperation, inclusion of children, study designs requiring fewer patients, equivalent-control designs, use of EEG and video seizure counting, and better syndrome identification will be required.