FDA Approves Extended-Release Lamotrigine for Adjunctive Treatment of Epilepsy

Yael Waknine

June 03, 2009

June 3, 2009 — The FDA has approved lamotrigine extended-release tablets (Lamictal XR, GlaxoSmithKline) as once-daily adjunctive therapy for partial-onset seizures with or without secondary generalization in epileptic patients aged 13 years and older. The enteric-coated tablets use a proprietary technology (DiffCORE, GlaxoSmithKline) that allows a controlled release of lamotrigine into the stomach for absorption into the bloodstream.

"Many patients require multiple doses of one or more medications to control their epilepsy, which makes taking their medicines even more challenging," said Dean Naritoku, MD, professor and chairman of neurology, University of South Alabama, Mobile, in a company news release. "Lamictal XR is an important once-daily advance for patients with epilepsy who still experience seizures while taking their current therapy."

The approval was based on data from an international, multicenter, randomized, double-blind, placebo-controlled trial (Armor) of 236 patients who were experiencing 4 to 6 seizures per week while receiving a stable regimen of 1 or 2 antiepileptic drugs.

Study results showed that once-daily use of extended-release lamotrigine significantly decreased the incidence of partial seizures from baseline relative to placebo (47% vs 25%; P = .0001) during the entire 19-week study period, which consisted of a 7-week dose-escalation phase and a 12-week maintenance phase.

These findings were supported by those of a second study (COMPASS; n = 44) showing that patients can be switched from the twice-daily immediate-release formulation of lamotrigine to the once-daily extended-release formulation while maintaining comparable blood levels of the drug, regardless of concomitant antiepileptic drug therapy.

The FDA warns that lamotrigine is linked to a risk for life-threatening serious rash that is increased by coadministration with valproate and by exceeding the recommended initial dose or dose escalation of extended-release lamotrigine.

Patient titration kits are available to provide extended-release lamotrigine at doses consistent with the recommended titration schedule during the initial 5 weeks of therapy, based on medications for patients with partial onset seizures.

Lamotrigine immediate-release tablets and chewable dispersible tablets previously were approved as adjunctive treatment for partial seizures, the generalized seizures of Lennox-Gastaut syndrome, and primary generalized tonic-clonic seizures in adults and pediatric patients aged 2 years and older.

The immediate-release formulation also may be used for conversion to monotherapy in adults with partial seizures who are receiving treatment with carbamazepine, phenytoin, phenobarbital, primidone, or valproate as a single antiepileptic drug, and for the maintenance treatment of bipolar disorder to delay the time to occurrence of mood episodes in patients receiving standard therapy for acute episodes.

Full Prescribing Information


Comments on Medscape are moderated and should be professional in tone and on topic. You must declare any conflicts of interest related to your comments and responses. Please see our Commenting Guide for further information. We reserve the right to remove posts at our sole discretion.
Post as: