Medtronic is reporting that its deep brain stimulation device, the Intercept™ Epilepsy Control System, has been shown to “significantly reduced seizure frequency among patients with medically refractory epilepsy with partial-onset seizures.” According to a brief statement on the firm’s website, Medtronic will be seeking a premarket regulatory approval from the FDA for this system. We are guessing that the indication for this device will likely be the prevention or treatment of refractory seizures.
From the press release by Medtronic:
In a clinical trial supported by Medtronic, Inc., deep brain stimulation (DBS) significantly reduced seizure frequency among patients with medically refractory epilepsy with partial-onset seizures, a form of the neurological condition that does not respond well to antiepileptic drugs. The study, known as SANTE® (Stimulation of the Anterior Nucleus of the Thalamus in Epilepsy), is the only prospective, randomized, double-blind pivotal study to evaluate the use of Medtronic DBS for epilepsy. The findings were presented at the American Epilepsy Society (AES) Annual Meeting in Seattle by Robert Fisher, M.D., professor of neurology and director of Stanford Epilepsy Center and principal investigator for the SANTE study.
The results from the SANTE study showed that stimulating the left and right anterior nucleus of the thalamus – the brain’s central message and relay station – with Medtronic’s DBS therapy for epilepsy in conjunction with epilepsy medications produced a statistically significant median percent reduction in seizures compared to a no stimulation control group at the end of the blinded phase of the study (38 percent in the treatment groups vs. 14.5 percent in the control group with both groups continuing on their epilepsy medications without change during this phase). The results from long-term follow up during the trial show even greater reductions in seizures for the majority of patients. Key data highlights:
Of the 87 study participants who completed the diaries through month 13, 40 percent experienced a 50 percent or greater reduction in their baseline rate of seizures 13 months after implant. Of the 86 study participants who had at least three months of data from long-term follow up, 60 percent experienced a 50 percent or greater reduction in their baseline rate of seizures. These long-term follow up results represent outcomes from the last three months of available data for each patient (ranged from 12 to 49 months after implant with median follow up of 31 months). During this same long-term follow-up period (last three months of data for each patient), median seizure frequency was reduced by approximately two-thirds, nine percent of study participants had no seizures and 19 percent experienced a greater than 90 percent reduction in seizure frequency.
“Approximately one-third of patients with epilepsy have uncontrollable seizures with little or no response to medications, surgery or other treatments, which has a significant impact on their quality of life,” said Dr. Fisher. “Based on the seizure frequency results from the SANTE study, DBS may become a promising treatment option for appropriate patients.”
The types of adverse events reported in the study were consistent with known adverse events associated with epilepsy and implanted DBS systems. There were no serious unanticipated device-related adverse events. Twenty-two percent of the total reported events were related to stimulation, hardware or procedure and three percent of all adverse events were serious device-related effects. The infection rate was 10.9 percent and the rate of asymptomatic intracranial hemorrhage was 1.3 percent per lead implant. While there was a significantly higher incidence of spontaneously self-reported depression, memory impairment, and anxiety in the active group compared to the control group during the blinded phase, most events resolved spontaneously or with changes in medication or stimulation parameters. Objective neuropsychological assessment at the end of the Blinded Phase did not confirm any statistical differences between the active and control groups.
Patients in the study have had epilepsy for an average of 22 years and 54 percent of the 110 implanted patients had previously undergone resective surgery and/or vagal nerve stimulation therapy. Benefit also was seen in patients with prior history of vagal nerve stimulation or previous epilepsy surgery. The study is still ongoing with some patients having received DBS therapy for more than four years.
Press release: Data From Pivotal Study Show Medtronic Deep Brain Stimulation Therapy Reduced Seizure Rate in Patients With Severe Epilepsy…
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