Abstracts

This study was designed to investigate the efficacy and safety of long-term zonisamide as monotherapy or adjunctive therapy by conducting a retrospective chart review of patients with epilepsy. Charts of neurology clinic patients with a variety of seizure types were reviewed to identify patients treated with zonisamide for [ge]3 months. The efficacy of zonisamide was based on the reduction in seizure frequency, and safety of zonisamide was evaluated by reports of adverse events (AEs). Both results were based on physicians[apos] notes and patient reporting. A total of 112 male and female zonisamide-treated patients were identified for the study. Of these, 90 patients (n=45 monotherapy, n=45 adjunctive therapy) who were taking zonisamide therapy for [ge]3 months were included in the efficacy analysis; all 112 patients were included in the safety analysis. The patients[apos] ages ranged from 14 to 97 years (mean, 54 y). The duration of zonisamide therapy ranged from 3 to 46 months (mean, 24.3 mos), and the zonisamide dosages ranged from 100 to 1000 mg/d (mean, 324 mg/d). Complex partial seizures and partial seizures with secondary generalization were the most common seizure types. Of the 90 patients included in the efficacy analysis, 38 (42%; n=25 monotherapy, n=13 adjunctive therapy) were seizure free on zonisamide at the end of the study. A [ge]50% seizure frequency reduction was observed in 26 patients (29%; n=9 monotherapy, n=17 adjunctive therapy). A total of 15 zonisamide-treated patients experienced either no effect (10%; n=4 monotherapy, n=5 adjunctive therapy) or an unknown effect (7%; n=4 monotherapy, n=2 adjunctive therapy) on seizure frequency. Thirty of the 112 patients (27%) reported AEs and these included ([ge]2% of subjects) weight/appetite loss (5.4%), fatigue (4.5%), sedation (2.7%), and gastrointestinal distress (2.7%). A total of 22 patients (20%) discontinued zonisamide therapy; 8 discontinued for unknown reasons, 1 due to ineffective seizure control, and 13 patients (12%) discontinued due to AEs, which included GI distress, rash, weight loss, and fatigue. Zonisamide was effective as long-term monotherapy or adjunctive therapy in patients with various seizure types, and was safe and well tolerated in these patients. (Supported by Eisai Inc.)