This study will evaluate the efficacy and safety of Rufinamide in reducing seizure frequency in subjects with partial seizures not fully controlled despite treatment with 1 to 3 concomitant antiepileptic drugs.

Inclusion Criteria:

• Male and Female patients between 12 and 80 years of age
• Dx of epilepsy with partial onset seizures woth or woth out secondarily generalized seizures
• Non controlled partial seizures despite treatment with 2 different AEDs for at least 2 years
• must have 6 seizures during baseline
• current treatment with maximum of 3 AEDs
• stable dose of AED(s)for at least 1 month
• if patient has VNS, must have been implanted 6 months prior to randomization

Exclusion Criteria:

• Participation in any investigational product for at least 1 month prior to visit 1
• Presence of non-motor simple partial seizures only
• presence of generalized epilepsies
• Evidence of clinically significant disease
• Clinically significant ECG
• Psychogenic seizure in previous year
• History of drug/alcohol abuse
• History of suicide attempt
• Multiple drug allergies
• Concomitant felbamate use
• Need for frequent rescue benzodiazepines
• Concomitant use of vigabatrin
• All patients diagnosed with congenital short QT syndrome