A Trial to Evaluate the Long Term Safety and Tolerability of Lacosamide Taken as Monotherapy in Adults With Partial-onset Seizures

Inclusion Criteria: * Subject is male or female and ≥16 years of age * Subject has a diagnosis of epilepsy, having experienced unprovoked partial-onset seizures (IA, IB, or IC with clear focal origin) that are classifiable according to the International League Against Epilepsy (ILAE) Classification of Epileptic Seizures, 1981 * Subject experiences partial-onset seizures despite appropriately chosen and adequately tried treatment with 1 antiepileptic drug (AED) * Subject has been treated for epilepsy with a stable dose of 1 marketed AED The use of benzodiazepines is permitted as rescue therapy for epilepsy. Benzodiazepines may have been used as needed but not more frequently than once per week. Exclusion Criteria: * Subject has a history or presence of seizures of other types than partial onset (IA, IB, or IC with clear focal origin) * Subject is taking benzodiazepines for a nonepilepsy indication (Exception: Concomitant use of benzodiazepines is allowed if the subject is taking them on a regular basis, has been on a stable dose for at least 1 month prior to Visit 1, and does not require changes in the dosage and administration throughout the study period. However, concomitant use of benzodiazepines on an as needed basis is not permitted.) * Female subject who is pregnant or nursing, and/or a woman of childbearing potential who is not surgically sterile, 2 years postmenopausal or does not practice 1 highly effective method of contraception, unless sexually abstinent, for th…