Despite the introduction of new antiepileptic drugs into overseas clinical settings after 1990's, there still exist those patients who cannot control seizures, and thus the advent of newer antiepileptic drugs is being desired. This is a multicenter, open-label, extension study in patients who have completed the preceding study (333369-KJ-02) and scheduled to continue until the study drug is approved. This study consists of Period 1 (1 year) and Period 2 (only in Japan; planned to continue until the drug is approved Primary objective of this study is to evaluate the long-term safety (Adverse event, Lab test, Electrocardiogram, Vital signs, Pregnancy test, Physician Withdrawal Checklist) of RWJ-333369 at doses between 200-800 mg/day in patients who have completed the preceding study. Secondary objective of this study is to evaluate the long-term effectiveness of RWJ-333369 at doses between 200-800 mg/day in patients who have completed the preceding study. Period 1:RWJ-333369 will be started at 400 mg/day. RWJ-333369 100 mg tablets or 200 mg tablets will be orally administered with noncarbonated water twice daily. The dose will be adjusted between 200 mg/day and 800 mg/day based on effectiveness and tolerance. Period 2: The dose will be adjusted between 200 mg/day and 800 mg/day based on effectiveness and tolerance.
