Efficacy And Safety Of Adjunctive Zonisamide In Adult Patients With Refractory Partial-onset Epilepsy A Randomized, Uble-Blind, Placebo-Controll Trial

ObjectiveClinical studies have reported that zonisamide is effective for a multiple range of seizure types, including refractory partial-onset seizure. However, there have been no reported studies of the efficacy of zonisamide in Chinese population to date. The aim of the present study was to evaluate the efficacy and safety of zonisamide in the treatment of adult Chinese patients with refractory partial-onset epilepsy.MethodsThis was a randomidzed, double-blind, placebo-controlled trial conducted over a 16-week period. 104 patients with refractory partial-onset epilepsy were enrolled. Participants were randomly assigned to receive add-on zonisamide or placebo. Zonisamide was titrated to a target dosage of 300 or 400 mg/day. Seizure frequency and adverse effects were documented. Results102 patients completed this trial. Zonisamide showed significantly greater efficacy compared with placebo (responder rate 55.8% vs 36.0%, P<0.05), including 55.2% (16 of 29 patients) in zonisamide 300mg/day arm and 56.5% (13 of 23 patients) in the zonisamide 400mg/day arm. Zonisamide 300 and 400mg/day showed similar efficacy (P>0.05). Moreover, similar efficacy of zonisamide was found in the control of complex partial seizures, simple partial seizures and secondary generalized seizures. There was no difference in the incidence of adverse effects between zonisamide and placebo. Reported adverse effects in the zonisamide group involved the digestive system (32.5% of total adverse effect in the group)[including transient increases in liver enzymes(27.8%)], weight change (30.2%),the haematological system (15.1%), neurological/psychiatric system (10.3%), the urinary system (7.9%) and the cardiovascular system (4.0%). Only digestive system adverse effects constituted a significantly higher proportion of adverse effects in the zonisamide group than in the placebo group(32.54% vs 30.23%, P<0.05).ConclusionZonisamide 300-400 mg/day is effective and well tolerated as an adjunctive drug in adult Chinese patients with refractory partial-onset epilepsy.