Eisai reported positive data from a Phase III trial evaluating the anti-epilepsy drug Zonegran® (zonisamide) as adjunctive therapy in pediatric patients with partial-onset seizures. The placebo-controlled CATZ study included 207 patients aged 6-17 years with partial-onset seizures, who were already taking one or two anti-epileptic drugs. Participants were randomized to receive either Zonegran or placebo in addition to their existing medications. The primary endpoint was the proportion of patients who responded to therapy by a 50% or more reduction in seizure frequency after 12 weeks of maintenance therapy. The results showed that 50.5% of patients responded positively to the addition of Zongran, compared with a response rate of 31% among placebo patients.