New information helps in treating generalized tonic-clonic seizures

Data published in today's issue of Pediatrics show that lamotrigine (LAMICTAL) is an effective add-on therapy for the treatment of Primary Generalized Tonic-Clonic (PGTC) seizures in a subgroup of children and adolescents. This is the first published analysis of data from a randomized, double-blind, controlled clinical trial of PGTC seizures focusing on patients 2 to 20 years of age. PGTC seizures, also know as "grand mal" seizures, are the most common form of generalized seizures, occurring in approximately 20 percent of patients with epilepsy. Lamictal is not currently indicated for the treatment of PGTC seizures.

"PGTC seizures are more common in children than in adults, and are associated with increased risk of injury or death," said Edwin Trevathan, M.D., M.P.H., Director of the Division of Pediatric and Developmental Neurology at Washington University School of Medicine and Neurologist-in- Chief, St. Louis Children's Hospital, St. Louis, MO, key investigator of the clinical study. "These study findings are important since physicians and neurologists continue to have limited treatment options available for generalized seizures in this age group."

PGTC seizures usually occur without warning and are associated with wide- ranging physical and behavioral changes with potentially life-threatening complications.

Patients who experience PGTC seizures become stiff, lose consciousness, and jerk repetitively. Patients may fall to the ground, bite their tongue, and/or lose bladder control. Serious injury including bone fractures can occur. The seizure will typically last for a few minutes and then be followed by a period of drowsiness, confusion, headache, and sleep. For some people who have this type of seizure, it can take many hours to fully recover.

ABOUT THE STUDY

A randomized, double-blind, placebo-controlled study was conducted to assess the efficacy and tolerability of adjunctive therapy with LAMICTAL in the treatment of PGTC seizures among patients 2 years of age and older. Investigators evaluated 117 patients, ages 2-55 years, with PGTC seizures inadequately controlled on 1-2 current AEDs and with evidence of PGTC seizures on electroencephalogram (EEG) and no past evidence of partial seizures. The treatment period consisted of an Escalation phase (7-12 weeks) and a Maintenance phase (12 weeks).

In a subgroup analysis of 45 patients 2-20 years of age, the median percent decrease from Baseline in PGTC seizures during the entire treatment period was 77 percent among patients receiving LAMICTAL and 40 percent in the placebo group (p=0.044). The median PGTC seizure counts per month were significantly improved for all treatment phases in patients receiving LAMICTAL compared to placebo.

The most commonly reported adverse events in this analysis were headache (10% LAMICTAL, 25% placebo), nasopharyngitis (14% LAMICTAL, 4% placebo), and convulsion (10% LAMICTAL, 17% placebo). One patient from each treatment group discontinued due to an adverse event. No serious rashes occurred among patients taking LAMICTAL or placebo. No patient experienced worsening of myoclonus.

Overall, adjunctive therapy with LAMICTAL appeared to be effective in controlling PGTC seizures among patients 2 to 20 years of age and was associated with a favorable tolerability profile.

ABOUT EPILEPSY

Epilepsy, defined by recurrent unprovoked seizures, is a change in sensation, awareness, or behavior brought about by an electrical disturbance in the brain. The kind of seizure a person has depends on which part and how much of the brain is affected by the disturbance that produces seizures. Generalized seizures are seizures that involve the entire brain from the outset. In most cases, the cause of epilepsy is unknown. According to the Epilepsy Foundation, epilepsy affects more than 2.5 million people in the United States of all ages.

ABOUT LAMICTAL

LAMICTAL is indicated

1) as adjunctive therapy in patients as young as 2 years with partial seizures or the generalized seizures of Lennox-Gastaut syndrome (LGS) and

2) for conversion to monotherapy in adults with partial seizures taking carbamazepine, phenytoin, phenobarbital, primidone, or valproate as the single AED.

- Safety and effectiveness of LAMICTAL have not been established

1) as initial monotherapy,

2) for conversion to monotherapy from AEDs other
than carbamazepine, phenytoin, phenobarbital, primidone, or valproate,

3) for simultaneous conversion to monotherapy from 2 or more concomitant
AEDs, or

4) in patients below the age of 16, other than those with
partial seizures and the generalized seizures of LGS.

LAMICTAL is also approved for maintenance treatment of bipolar I disorder to delay the time to occurrence of mood episodes (depression, mania, hypomania, mixed episodes) in adult patients treated for acute mood episodes with standard therapy. The effectiveness of LAMICTAL in the acute treatment of mood episodes has not been established.

Serious rashes requiring hospitalization and discontinuation of treatment have been reported in association with the use of LAMICTAL. The incidence of these rashes, which have included Stevens-Johnson syndrome, is approximately 0.8 percent (8 per 1000) in pediatric patients under the age of 16 years receiving LAMICTAL as adjunctive therapy for epilepsy, and 0.3 percent (3 per 1000) in adults on adjunctive therapy for epilepsy.

In clinical trials of bipolar and other mood disorders, the rate of serious rash was 0.08 percent of adult patients who received LAMICTAL as initial monotherapy and 0.13 percent of adult patients who received LAMICTAL as adjunctive therapy. In a prospectively followed cohort of 1,983 pediatric patients taking adjunctive LAMICTAL, there was one rash-related death.

ABOUT GLAXOSMITHKLINE

GlaxoSmithKline, with U.S. operations in Philadelphia, P.A. and Research Triangle Park, N.C., is one of the world's leading research-based pharmaceutical and healthcare companies.

GlaxoSmithKline is committed to improving the quality of human life by enabling people to do more, feel better, and live longer. More information on GlaxoSmithKline is available at the company's Web site at www.gsk.com.