Topiramate monotherapy for childhood absence seizures: an open label pilot study
1Neuroscience Unit, Institute of Child Health, Guilford Street and Great Ormond Street Hospital for Children NHS Trust, Great Ormond Street, London, UK. hcross@ich.ucl.ac.uk
Insights
Topiramate shows promise for treating childhood absence epilepsy, with one child becoming seizure-free. Further research is needed to determine optimal dosing for this epilepsy syndrome.
Area of Science:
- Pediatric Neurology
- Clinical Pharmacology
- Epilepsy Research
Background:
- Childhood absence epilepsy (CAE) is characterized by brief episodes of impaired awareness.
- Existing antiepileptic drugs (AEDs) are not effective for all children with CAE.
- Topiramate is an established AED with a broad spectrum of activity.
Purpose of the Study:
- To evaluate the therapeutic efficacy and tolerability of topiramate in children with typical absence seizures.
- To assess the impact of topiramate on seizure frequency and electroencephalogram (EEG) findings.
Main Methods:
- An open-label, single-site pilot study involving five children with typical absence seizures.
- Topiramate was initiated at 1 mg/kg/day and titrated up to 12 mg/kg/day.
- Response was evaluated after 6 weeks using ambulatory EEG and seizure diaries.
Main Results:
- One child achieved complete seizure freedom with topiramate treatment.
- Two patients experienced initial seizure reduction, with improved EEG findings upon dose adjustment.
- Two patients showed no improvement in seizure frequency; transient mood changes were observed in two participants.
- No participants were withdrawn due to adverse effects.
Conclusions:
- Topiramate demonstrates potential as an effective treatment for childhood absence epilepsy.
- Further controlled studies are necessary to establish optimal dosing and confirm efficacy.
Abstract:
This open-label, single-site, pilot study evaluated the therapeutic usefulness of topiramate in five children with typical absence seizures defined as loss of awareness associated with 3 Hz spike-wave activity on 24 hour ambulatory electroencephalogram (EEG). The children were previously untreated or treated unsuccessfully using other antiepileptic medication. Topiramate was initiated at a dose of 1 mg x kg (-1)day (-1), titrated twice weekly in 1 mg x kg (-1)day (-1)increments to 12 mg x kg (-1)day (-1)or individual maximally tolerated dose. Response was assessed after 6 weeks with ambulatory EEG monitoring and patient/parent record of seizure counts. All children completed the study. One previously untreated child became seizure-free on 5 mg x kg (-1)day(-1) topiramate, with no residual spike-wave activity at the final visit. In two patients, the frequency of seizures decreased in the early phases of titration, but rose to baseline levels as the topiramate dose was increased. With a reduction in dose to 6 mg x kg (-1)day (-1), seizure control improved, with substantial reductions in spike-wave activity. Seizure counts were not improved in the two remaining patients. Transient mood changes were noted in two patients. No child was withdrawn secondary to adverse effects. The results suggest that topiramate may be effective in childhood absence epilepsy. Controlled studies are now required to identify the clinically optimal dose.
