A double-blind controlled clinical trial: oxcarbazepine versus sodium valproate in adults with newly diagnosed epilepsy

Abstract

Oxcarbazepine (OXC) has been licensed as monotherapy and add-on treatment in epilepsy patients with partial seizures with or without secondarily generalized seizures (PS) and generalized tonic-clonic seizures without partial onset (GTCS). Its use as monotherapy in adults with newly diagnosed epilepsy was investigated in a double-blind, randomized, parallel-group comparison with sodium valproate (VPA). Two-hundred and forty-nine patients with either PS or generalized seizures aged 15-65 years were randomized. After a retrospective baseline, patients were randomized to VPA or OXC in a 1:1 ratio. The double-blind treatment phase was divided into two periods, flexible titration and maintenance. The titration period was 8 weeks followed by 48 weeks of individualized, maintenance treatment given three times a day. Three primary analyses were used to assess efficacy, tolerability, and the association between the two. In the efficacy analyses comprising 212 patients who had at least one seizure assessment during the maintenance period, no statistically significant difference at the 5% level was found between the treatment groups. Sixty patients (56.6%) in the OXC group and 57 patients (53.8%) in the VPA group were seizure free during maintenance treatment. Fifty-two patients in the OXC group discontinued treatment prematurely (15 because of tolerability reasons) compared to 41 patients in the VPA group (ten due to tolerability reasons). There was no statistically significant difference between the treatment groups with respect to the total number of premature discontinuations or those due to adverse experiences. This trial provides support for the efficacy and safety of OXC as first-line treatment in adults with PS and GTCS.