The study provides evidence that confirms the efficacy of zonisamide 50 mg/d for reduction in "off" time in PD patients with wearing-off phenomena.

Background: We previously showed that zonisamide significantly improved parkinsonian symptoms by a multicenter, double-blind clinical trial. Aim: To confirm the efficacy of zonisamide on Parkinson's disease, a phase 3, randomized, placebo-controlled, multicenter, double-blind trial was carried out in Japan. Methods: Participants had advanced Parkinson's disease taking L-dopa with at least one other antiparkinson drug, but were developing a deterioration of response to L-dopa therapy. The trial consisted of a 2-week initial phase (singleblind, with administration of placebo) and a 12-week treatment phase (doubleblind, with patients randomly assigned to either placebo, or zonisamide 25 or 50 mg/day). Patients were evaluated using the Unified Parkinson's Disease Rating Scale (UPDRS). Results: A total of 185 patients (mean age 64.8 years; mean duration 7.5 years) were included in the efficacy analysis (placebo, zonisamide 25 mg, 50 mg; 63, 61, 61 patients, respectively). When compared with the placebo group, the UPDRS Part III total score at final assessment (the primary end-point for efficacy) significantly improved (P = 0.029) in the zonisamide 25 mg group. After 12 weeks of therapy, the UPDRS Part III total score significantly improved in both the zonisamide 25 mg (P = 0.038) and 50 mg groups (P = 0.049), compared with the placebo group. Neither the zonisamide 25 mg nor 50 mg group differed significantly from the placebo group in the incidence of adverse events (P = 0.363 and P = 0.713, respectively). Conclusion: These findings confirmed that zonisamide is well tolerated and efficacious in the treatment of advanced Parkinson's disease.

The present study evaluated large-scale claims-based datasets and found that high-dose prescriptions and antipsychotic polypharmacy among Japanese outpatients were not as prevalent as has been previously thought. Copyright © 2017 John Wiley & Sons, Ltd.

Background: Although previous phase II and III clinical trials conducted in Japan showed that zonisamide improved parkinsonism in patients with dementia with Lewy bodies (DLB), some differences in efficacy outcomes were observed between the trials. Objective: We aimed to further examine the efficacy and safety of zonisamide in DLB patients with parkinsonism in a post hoc analysis of pooled data from the previous phase II and III trials. Methods: Both trials featured a 4-week run-in period followed by a 12-week treatment period with a double-blind, placebo-controlled, parallel-group, randomized, multicenter trial design. In our pooled analysis, the primary outcome was the change in Unified Parkinson’s Disease Rating Scale (UPDRS) part III total score. Other outcomes included the changes in Mini-Mental State Examination (MMSE) and Neuropsychiatric Inventory-10 (NPI-10) scores, and the incidence of adverse events. Results: Zonisamide significantly decreased the UPDRS part III total and individual motor symptom scores but did not affect the MMSE or NPI-10 scores at week 12. There was no difference in the incidence of adverse events between the zonisamide and placebo groups except for decreased appetite, which had an increased frequency in the zonisamide 50 mg group compared with placebo. Conclusion: Our findings indicate that zonisamide improved parkinsonism with DLB without deterioration of cognitive function and or worsening behavioral and psychological symptoms of dementia.