Positive Phase III data published for Zonegran in Epilepsy-Eisai

Zonegran (zonisamide), from Eisai, continues to be well-tolerated and efficacious when used as long-term monotherapy for the treatment of partial onset seizures in adults with newly diagnosed Epilepsy, as demonstrated by a new publication in Epilepsia. The extension study assesses zonisamide versus carbamazepine monotherapy in patients from 72 sites in 17 countries in Europe, Asia, Australia, and South Africa, with over three-quarters exposed to over 24 months of treatment. No other currently available anti-epileptic drug has been studied in a double blind monotherapy setting over such a long duration of treatment.

The Phase III non-inferiority trial (Study 310) shows that once-daily zonisamide monotherapy demonstrates favourable long-term safety and maintenance of efficacy in the treatment of partial onset seizures in adults with newly diagnosed epilepsy. Retention rates are similar between treatment groups at all time-points throughout the extension study. The proportion of patients who remain seizure free for ?24 months is also similar for zonisamide (32.3%) and carbamazepine (35.2%).

The incidence of treatment-related TEAEs is 26.3% for zonisamide compared with 19.6% for carbamazepine and the most frequently reported treatment-related TEAEs are decreased weight (5.1% vs. 0%), decreased appetite (3.6% vs. 0%), memory impairment (2.9% vs. 3.2%), and decreased hemoglobin (1.5% vs. 3.2%). Most TEAEs are of mild or moderate intensity. See: "Long-term safety and efficacy of zonisamide versus carbamazepine monotherapy for treatment of partial seizures in adults with newly diagnosed epilepsy: Results of a phase III, randomized, double-blind study." Baulac, M. et al. Epilepsia 2014;55:1534-1543