Epilepsy Drug Zonisamide Well Tolerated in Children

In children with epilepsy, Zonegran (zonisamide) was well tolerated over a study period of one year, according to research published in the April 2014 issue of Epilepsia.

Researchers from the University of Florence in Italy studied 144 children aged 6-18 years after administering either placebo or zonisamide 1 mg/kg/day, up to 8 mg/kg/day for a maximum of 500 mg/day. Throughout the study period, which lasted between 45-57 weeks, the dosage was adjusted to reflect patients’ tolerability and response.

The researchers measured safety assessments like treatment-emergent adverse events (TEAEs), clinical laboratory parameters, and vital signs. The participants’ growth and development was also measured on scales such as the Tanner stages, which assess physical development in children, adolescents, and adults; hand x-rays; Child Behavior Checklist (CBCL); School Performance questionnaire; Physical and Parent/Guardian Global Impression of Change tests; and Controlled Oral Word Association Test (COWAT) for verbal fluency. Although the primary efficacy assessment was the responder rate, the researchers also noted the seizure freedom rate during the study period.

Of the 144 patients, TEAEs occurred in 39 (27.1%), though there were low incidences of serious TEAEs (2.1%) and TEAEs leading to discontinuation (2.8%). Ninety-nine (68.8%) of the children completed the study, and 108 (75%) received zonisamide for ≥1 year. During the study period, 81 (56.3%) of the patients were responders and 16 (11.1%) achieved seizure freedom.

According to the Tanner staging and skeletal development testing results, growth and development proceeded as expected. The CBCL and School Performance scores saw minimal changes, and most patients were categorized “much improved”/”very much improved” on the Physician (73.8%) and Parents/Guardian (75.4%) Global Impressions of Change tests. The COWAT fluency scores experienced a median change of 2.0 and 0.5, respectively.

“Unfortunately, more than one-fourth of children with epilepsy remain refractory to treatment,” study contributor Renzo Guerrini, MD, said. “There is still a need for additional treatment options. The results of this one-year open-label extension of a randomized-controlled study of zonisamide are therefore particularly welcomed, and zonisamide could be a valuable treatment option for children with partial epilepsy.”