Trial Design: This is a randomized, double-blind, multicenter Phase IV study using a parallel group design with three treatment groups. The study will consist of a 6-week titration-phase and a 52-week maintenance phase. Patients who successfully complete the trial (final visit, V6) will be unblinded and offered either to continue on their current drug or be changed to an alternative antiepileptic drug (AED) treatment of choice.