The Food and Drug Administration (FDA) has granted premarket approval of deep brain stimulation (DBS) therapy to Medtronic (Dublin, Ireland) for adjunctive treatment to reduce frequency of partial-onset seizures, in individuals 18 years of age or older who are refractory to 3 or more antiepileptic medications. DBS therapy for epilepsy stimulates the anterior nucleus of the thalamus (ANT).
This approval is based on data from the blinded phase and a 7-year follow-up phase of the stimulation of the ANT in epilepsy (SANTE) trial, a prospective randomized double-blind pivotal study. The SANTE trial collected data from 110 patients who were implanted with a Medtronic DBS system at 1 of 17 participating centers in the US. The median total seizure frequency reduction from baseline was 40.4% versus 14.5% percent for the placebo group at 3 months. After 7 years, patients who underwent the procedure and had open-label ongoing therapy had a 75% median total seizure frequency reduction from baseline. Freedom from seizure for at least one 6-month period occurred in 18% of subjects during the 7 years of data collection, including eight subjects (7 percent) who were seizure-free for the preceding 2 years. Seizure severity and quality of life scales both showed statistically significant improvements from baseline at year 7. No significant cognitive declines or worsening of depression scores were observed through the blinded phase or at year 7. Improved scores were observed at 7-years on measures of executive functions and attention.
"Many patients in the United States with severe epilepsy are not able to control their seizures with currently-available drugs and are not candidates for potentially curative surgery," said Dr. Robert Fisher, director of the Stanford Epilepsy Center, Stanford University, and lead principal investigator of the SANTE trial. "Epilepsy that is refractory to AED treatment is an unsolved problem, and DBS therapy will now serve as an important new treatment option, including for people with poorly localized or multiple regions of seizure origin."Next Story