Abstracts

Rationale: West syndrome is an age dependent epileptic encephalopathy, defined by the combination of clustered epileptic spasms and hypsarrhythmia in the electroencephalogram (EEG). This syndrome is usually refractory to the conventional antiepileptic drugs (AED). The high quality evidence regarding efficacy of antiepileptic drug against this condition is mainly limited to adrenocorticotropic hormone (ACTH). However there are major limitation in its use like its parenteral route of administration, high cost and frequent side effects. Zonisamide is an effective antiepileptic drug with emerging evidence to suggest potential efficacy in West syndrome. Ease of administration by oral route, cheaper cost are its advantages. Major limitations of the studies on zonisamide were lack of comparator, non randomized controlled design and diversity of protocols. The present study was planned to elucidate the safety, feasibility and effectiveness of high dose zonisamide therapy in comparison to the standard adrenocorticotropic hormone therapy. Methods: Thirty infants (6-12 months of age) with West syndrome were randomized to receive treatment with either adrenocorticotropic hormone or high dose oral zonisamide (4-25 mg/kg/day). The outcome measures included clinical response in terms cessation of epileptic spasms, improvement in neurodevelopmental score, resolution of hypsarrhythmia in electroencephalogram, and assessing the safety and feasibility of using zonisamide in infants with epileptic spasms. Results: The study observed efficacies in terms of cessation of epileptic spasms at day 14 of treatment (26.7% vs. 40%, p= 0.70), resolution of hypsarrhythmia at 2 weeks of treatment ( 20% vs. 33.3 %, p=0.68) , resolution of hypsarrhythmia at 6 weeks of treatment ( 35.7% vs. 71.4%, p=0.14) with high dose zonisamide therapy in comparison with adrenocorticotropic hormone. Conclusions: The study observed poor efficacy of both adrenocorticotropic hormone and zonisamide therapy. High dose oral zonisamide appeared to be safe and tolerable. The study suggests high dose zonisamide monotherapy might be one of the second line options for treatment of epileptic spasms. Funding: None