The object of this study is to assess the efficacy and safety of zonisamide as adjunctive therapy in patients with uncontrolled partial epilepsy.

The object of this study is to assess the efficacy and safety of zonisamide as adjunctive therapy in patients with uncontrolled partial epilepsy. Subject takes zonisamide for 16 weeks (4 weeks-titration period, 8 weeks maintenance period). Dose range of zonisamide is 100 ~ 400 mg/day and target dose is 300 mg/day. After 16 weeks, zonisamide efficacy is measured by seizure reduction rate (Each type of seizure: simple partial seizures [SPS], complex partial seizures [CPS], simple partial seizures evolving into generalized tonic-clonic convulsions [SGTC] and total seizure frequency), seizure free rate, responder rate, quality of life in epilepsy (QOLIE-31) and investigator's global evaluation scale. Safety of zonisamide in this study will be estimated by adverse event profile, retention rate and dose of exposure. The duration of this clinical study is 2 years including period of subject enrollment.

Inclusion criteria:

1. Epilepsy patient over 15 years old who agrees with Informed Consent Form
2. Patient who has classifiable uncontrolled partial epilepsy according to International Classification of Epileptic Seizures.
3. Patient who has 3 ~ dozens of partial seizure (average more than once seizure per 4 weeks) last 12 weeks despite taking 1 ~ 3 antiepileptic drug(s).
4. Patient who takes 1 ~ 3 marketed antiepileptic drug(s) excluding zonisamide at point of enrollment time.
5. Before study visit, patient who takes stable dose of antiepileptic drug more than 4 weeks.

Exclusion criteria:

1. Patient who has progressive central nervous system (CNS) disorder and/or degenerative disease of the brain.
2. Patient who experiences pseudoseizures and/or who has uncountable clusters.
3. Patient who has serious systemic or drug metabolism affecting disorder .
4. Upward of doubled normal glutamic oxaloacetic transaminase (GOT), glutamic pyruvic transaminase (GPT), bilirubin, blood urea nitrogen (BUN), creatinine levels.
5. Patient who has absolute neutrophil counts <1800/mm3 or platelets <100,000/mm3.
6. Patient who has medical history of renal stones.
7. Patient who is allergic to sulfonamide.
8. Medical history of medicinal poisoning and/or alcoholism and/or serious psychological disorder.
9. Pregnant women, lactating women, women of childbearing age who do not use a preventive method of conception.
10. A terminal patient and/or a scheduled surgical patient.
11. Patient who has medication history of zonisamide.
12. Patient who participated other clinical trial within the last 12 weeks at point of enrollment time of this study.