A Study of the Efficacy and Safety of Pregabalin as Add-On Therapy for Partial Onset Seizures in Children Ages 4-16 Years

Inclusion Criteria: * Subjects and/or parent(s)/legally acceptable representative must be considered willing and able to sign consent, and complete daily seizure diaries and monitor seizure frequency. * Male and female epilepsy subjects, 4 to 16 years of age inclusive on the date of the Screening Visit. * Diagnosis of epilepsy with partial onset seizures classified as simple partial, complex partial or partial becoming secondarily generalized, according to the International League Against Epilepsy (ILAE) Diagnosis criteria. * Must have a partial onset seizure frequency of at least 3 seizures per 28 day period prior to screening. Must have a partial onset seizure frequency of at least 6 seizures and no continuous 4 week seizure free period during the 8 week baseline phase prior to randomization. * Currently receiving a stable dose of 1 to 3 antiepileptic drugs (stable within 28 days prior to screening). Exclusion Criteria: * Primary generalized seizures (including in the setting of co-existing partial onset seizures) which include, for example: Clonic, tonic and clonic-tonic seizures (note that partial onset seizures that become secondarily generalized are not exclusionary); Absence seizures; Infantile spasms; Myoclonic, myoclonic atonic, myoclonic tonic seizures. * Lennox Gastaut syndrome, Benign Epilepsy with Centrotemporal Spikes (BECTS) and Dravet syndrome. * A current diagnosis of febrile seizures, or seizures related to an ongoing acute medical illness. Any febrile seizures within 1 year of screening. * Status epilepticus within 1 year prior to screening. * Seizures related to drugs, alcohol, or acute medical illness. * Any change in AED regimen (type of medication or dose) within 28 days of the Screening Visit or during the Baseline Phase. * Progressive structural CNS lesion or a progressive encephalopathy.