A Study to Look at the Efficacy and Safety of Keppra® Extended Release Formulation - XR

A Double-blind, Placebo-controlled, Randomized Efficacy and Safety Study of Keppra® Extended Release Formulation - XR Once Daily as add-on Therapy in Subjects From 12 to 70 Years With Refractory Epilepsy Suffering From Partial Onset Seizures.

This is a safety and efficacy study of Keppra® extended release formulation - XR in patients with epilepsy.

Inclusion Criteria:

• Patients with a confirmed diagnosis of refractory epilepsy
• Patients must be receiving a stable dose of 1 - 3 concomitant Anti-Epileptic Drugs (AED)
• Female patients without childbearing potential. Female patients with childbearing potential are eligible if they use a medically accepted non-hormonal contraceptive method

Exclusion Criteria:

• Seizures occurring in clusters
• Status epilepticus within 3 months of Visit 1
• History of non-epileptic seizures
• Known allergic reaction or intolerance to pyrrolidine derivatives and/or excipients
• Pregnant or lactating women. Any woman with childbearing potential who is not using a medically accepted, non-hormonal method of birth control