Preliminary efficacy of levetiracetam in monotherapy.

The standard of care for prescribing antiepileptic drugs (AEDs) has come to favor the use of monotherapy when possible; i.e., when compa-rable efficacy can be achieved with fewer risks of adverse events and drug interactions. Most patients with epilepsy are started on one of the classic AEDs and, if it proves ineffective, another drug is tried, usually as monotherapy. While most of the newer AEDs that have come into clinical use in recent years are initially used as add-on therapy, their success at improving seizure control in combination treatments has led to their cautious use as monotherapy even before they have been approved for this indication. As a first study to determine the potential efficacy of levetiracetam in monotherapy, a withdrawal trial model was used. Patients who achieved adequate seizure control with levetiracetam as add-on therapy in a double-blind, placebo-controlled study entered a monotherapy phase of the trial in which the baseline AED was gradually withdrawn. Also, long-term data of 505 patients who received levetiracetam for refractory partial seizures were reviewed and found to include 49 patients still treated with levetiracetam monotherapy at the end of the study for a duration between 3 months and 5.5 years. Data from patients in the two trials lend supportive evidence that levetiracetam monotherapy is safe and effective for partial seizures.