FDA Approves New Epilepsy Drug for Persistent Seizures
Mar. 28, 2000 (Washington) -- Epileptic patients for whom current multidrug therapies have not been effective may soon find a new addition in their drug cocktails. On Tuesday, the FDA approved an anticonvulsant drug that may offer hope to Americans with persistent partial seizures.
"There is a critical need for new therapies for adults with epilepsy whose current treatment provides only limited control," Steven Schachter, MD, a neurologist at Harvard Medical School, tells WebMD.
The drug, Zonegran (zonisamide), works in a unique way, by blocking the release of sodium and calcium from nerve endings. Since 1989, it has been used in Japan, where it was developed.
In the U.S., it will be used for people with partial seizures, age 16 and up, as an add-on therapy to other epilepsy drugs. In partial seizures, just one part of the body is affected by the involuntary movements. According to a three-year study conducted by the nonprofit Epilepsy Foundation, about a third of the 2.3 million Americans with this disorder currently need multidrug cocktails.
Adults with partial seizures, in which the disorder affects a specific site on one side of the brain, also rarely go into complete remission, Schachter tells WebMD.
In clinical trials, about a fourth of patients saw a reduction in seizure rates when Zonegran was added to their existing therapy. The most frequently reported side effects were drowsiness, problems with muscular coordination, appetite loss, and slowed thinking.
The FDA initially approved Zonegran last spring, but at that time, the label included a so-called "black box warning," a stressed safety warning that the drugmaker, Elan Corp., did not think was merited.
The current label has no such warning. A spokesman for the company says Elan expects to begin marketing the 100 mg capsule in April, and it should be available sometime in May.
Zonegran could also become an important primary treatment option, says Schachter, who points out that very few epilepsy drugs initially are approved for first-line therapy. But the Epilepsy Foundation's excitement about its approval should not be considered an endorsement, he says.
Zonegran's safety and efficacy is represented by about a million patient years of exposure, based upon its use in Japan, the company says in a press release. "We believe Zonegran will be a welcome addition to the roster of treatment for epilepsy," says Elan CEO Donal Geaney.