Research has come a long way in providing effective treatment for people with epilepsy, but for some, it just is not enough. Despite adequate and therapeutic doses of medication, many still continue to experience several seizures a month. But according to researchers from the University of Michigan, a drug called oxcarbazepine may provide relief to those who continue to have a type of seizure known as a partial seizure, even if they have already been through the gamut of other medications.
In their study, researchers found that oxcarbazepine, sold under the brand name of Trileptal, was safe and effective for this population. They followed 87 patients, some as young as 12 years old, who had partial seizures that remained uncontrolled despite the fact that they were on medication. The study participants were first tapered off of their regular drug regimens, and then they were divided into two treatment groups. One group received a low dose of 300mg/day and the other group a much higher dose of 2,400 mg/day of oxcarbazepine. (The drug’s manufacturer currently recommends a daily dose of 1200 mg/day.)
The results, says study author Ahmad Beydoun, M.D., associate professor of neurology and director of the Comprehensive Epilepsy Center at the University of Michigan, are encouraging and he believes that the patients responded well to this drug. In the group receiving 2400 mg/day, 12 percent remained free of seizures and almost half had a 50 percent reduction in the number of seizures they were experiencing. The results were less encouraging for those on the lower dose — none of the patients became seizure free.
Epilepsy is a neurological disorder and affects more than 2.3 million American adults and children. It is characterized by seizures, which occur when specific brain cells release high amounts of electrical energy and in turn, trigger a sudden loss of control over movement, thought or awareness.
There are many types of seizures, and experts have divided them loosely into generalized and partial seizures. The most common type is the partial seizure, which occurs when the disturbance takes place in just one area of the brain, and affects whatever physical or mental activity that particular region controls. The generalized seizure happens when a massive burst of electrical energy occurs throughout the brain at one time, causing unconsciousness, convulsions and other severe effects.
“In epilepsy drug therapy, tolerability and efficacy are often closely related,” says Beydoun. “One of the challenges in treating this disorder is the side effects associated with the standard antiepileptic drugs.” Many patients cannot control their seizures because they are unable to tolerate high enough doses of their medication. For the most part, oxcarbazepine was well tolerated by the people in the study, and the majority of them were able to reach the highest recommended dose, which may partially explain why it worked so well for them.
Some epilepsy drugs are given in combination with other drugs, while some are used alone in what is called monotherapy. This study examined the efficacy of oxcarbazepine as a monotherapy, and it has been approved by the FDA to be used alone. However, Carmel Armon, MD, a professor of medicine at Loma Linda University in California and a Fellow with the American Academy of Neurology, is not yet ready to switch his patients over to oxycarbazepine. He believes that a closer look is needed at this drug, particularly if it is going to be used as monotherapy.
The four-month trial period, he points out, was not long enough to test the long-term efficacy of oxcarbazepine. “Even though it’s very gratifying that 12 percent had a chance to go seizure free on this medicine, the study design is not such that it would tell us how long that benefit would be sustained,” he says. Often a patient may do well initially on a new drug, but then after a few months, the same problems emerge. A much longer period of time is needed to truly test the efficacy of a drug, Armon believes.
Sometimes, just a change in a medication regimen can temporarily reduce the number of seizures, Armon points out, and so the reduction in seizures seen in the study could be partially attributed to that. “It’s frequently seen that when you make a change, a small percentage of your patients will be seizure free and then relapse, ” says Armon, who specializes in treating patients with epilepsy. “And in fact, many of my patients will give me a story that every change I’ve made seems to be a change for the better, and then they broke through.”
Armon believes while the study did demonstrate some effectiveness as a monotherapy in treating partial seizures, the results were just not that striking. Only a small percentage of the patients became seizure free, and since the study followed them for just four months, it is unknown how long the effect will last.
“Based on this knowledge,” says Armon, “They may better off working with the drugs that they are currently taking, and using oxcarbazepine as an add-on or addition to their current medication regimen.”