Topiramate as add-on drug in severe myoclonic epilepsy in infancy: an Italian multicenter open trial.

PURPOSE

This study was to evaluate the efficacy and safety of topiramate (TPM) in patients with severe myoclonic epilepsy in infancy (SMEI) and refractory seizures.

METHODS

We performed a prospective multicentric open label add-on study in 18 patients (age 2-21 years, mean 9 years) with SMEI and refractory seizures of different types. TPM was added to one or two other baseline drugs and the efficacy was rated according to seizure type and frequency.

RESULTS

TPM was initiated at a daily dose of 0.5-1 mg/kg, followed by a 2-week titration at increments of 1-3 mg/kg/24 h up to a maximum daily dose of 12 mg/kg. After a mean period of 11.9 months (range 2-24 months), three patients (16.7%) had 100% fewer seizures and ten patients (55.5%) had a more than 50% seizure decrease. In no patient there was a seizure worsening. Mild to moderate adverse events were present in four patients (22.2%), represented by weight loss, hypermenorrhoea, renal microlithiasis, nervousness and dysarthric speech.

CONCLUSION

TPM may be a useful drug in patients with SMEI, being particularly effective against generalized tonic-clonic seizures. Further studies are needed to evaluate the early use of this drug in such a severe syndrome.