Source: DGNews  |  Posted 2 years ago

By John Otrompke

BOSTON -- December 10, 2009 -- Lamotrigine appears to be tolerable in a new extended-release form, according to research presented here at the American Epilepsy Society (AES) 63rd Annual Meeting.

“Some patients who are on 1 antiepileptic drug still have breakthrough seizures,” explained lead author Alain Vuong, BS, GlaxoSmithKline, Research Triangle Park, North Carolina, speaking here at a poster presentation on December 7. “Instead of giving them 2 or 3 drugs, doctors like to try another drug first, to see if they can remain on monotherapy, which is always preferable.”

The research team described 3 separate clinical trials of lamotrigine, including a study of the drug as an adjunct treatment for intractable partial seizures, another study of the drug as an adjunct treatment for intractable grand mal seizures, and a trial of the drug as a conversion to monotherapy for partial seizures.

In the 3 trials described, 662 patients were exposed to at least 1 dose of lamotrigine. The median patient age was 32 years, and patients ranged in age between 13 and 80 years. Of the participants in the 3 trials, 51.5% were female.

Of the patients, 546 (82.5%) took the drug for 26 weeks or longer, and 270 (40.8%) took lamotrigine for 52 weeks or longer. Of those who received a dose of less than 300 mg/day, 43.1% were on the drug for at least 52 weeks, while among those who got between 300 and 500 mg/day, the number was 22%, and among those who received 500 mg/day or greater, it was 66.5%.

Although the drug appeared to be well tolerated in its new extended-release formulation, adverse events were reported. While the percentage of patients experiencing the most common adverse events such as dizziness and headache were few (10% and 6%, respectively), there were reports of rash, which can be life threatening. About 6% of patients reported rash in the 3 studies, and the rash was considered to be related to the drug in 4% of all patients. One of the cases of rash was considered to be a serious adverse effect.

Two of 4 deaths were considered to be treatment related. One was a case of acute cardiac failure in a 35-year-old woman who was receiving 500 mg/day of the drug, while the other was a case of drug toxicity in a 22-year-old woman who was receiving 200 mg/day. (“That case was an overdose,” noted coauthor Anne Hammer, BS, also of GlaxoSmithKline, adding that the death occurred in Russia.)

Funding for this study was provided by GlaxoSmithKline.

Presentation title: Long-Term Safety Data With Lamotrigine Extended-Release: A Meta-Analysis of 3 Controlled Trials. Abstract 3.302