NeuroPace, Inc., a company designs, develops, manufacturers and intends to market implantable devices for the treatment of neurological disorders, has received the US Food and Drug Administration (FDA) premarket approval for the NeuroPace RNS System, a treatment for adults with partial onset seizures that have not been controlled wit h two or more antiepileptic drugs.

The RNS System is a novel, implantable therapeutic device that delivers responsive neurostimulation, an advanced technology designed to detect abnormal electrical activity in the brain and respond by delivering imperceptible levels of electrical stimulation to normalize brain activity before an individual experiences seizures.

“We believe the RNS System has the potential to provide substantial improvement in quality of life to hundreds of thousands of people diagnosed with epilepsy in the US who are unable to achieve seizure control with medications,” said Frank Fischer, NeuroPace CEO. “We anticipate that physicians will be able to make this breakthrough therapy available to eligible patients in the very near future.”

The RNS System is indicated for use as an adjunctive therapy in reducing the frequency of seizures in individuals 18 y ears of age or older with partial onset seizures who have undergone diagnostic testing that localized no more than two epileptogenic foci, are refractory to two or more antiepileptic medications, and currently have frequent and disabling seizures (motor partial seizures, complex partial seizures and/or secondarily generalized seizures). The RNS System has demonstrated safety and effectiveness in patients who average three or more disabling seizures per month over the three most recent months (with no month with fewer than two seizures), and has not been evaluated in patients with less frequent seizures. It is estimated that approximately 400,000 people in the US meet these criteria and may benefit from treatment with the RNS System.

“The Epilepsy Foundation celebrates PMA approval of the RNS System,” said Phil Gattone, CEO of the Epilepsy Foundation. “We badly need new, effective therapies for the hundreds of thousands of people in this country as well as the millions around the world who live with uncontrolled seizures,” added Warren Lammert, chairman of the Epilepsy Foundation. “The RNS System from NeuroPace integrates the best of technology and neurology, and is an important new treatment option for these individuals and their families.”

The RNS System has been evaluated in three clinical trials, including a prospective, randomized, double-blinded, sham stimulation controlled pivotal study. The pivotal study primary effectiveness endpoint was met by demonstrating a 37.9 per cent reduction in seizure frequency in patients treated with responsive stimulation compared to a 17.3 per cent reduction in patients who were implanted with the device but were not receiving responsive stimulation during a three month blinded period. The difference is statistically significant (p=0.012). For those subjects who reached two years post-implant, 55% of the subjects experienced a 50% or greater reduction in seizures.

“The clinical community is eager for a new therapeutic option for patients who continue to suffer the devastating consequences of uncontrolled partial seizures,” said Martha Morrell, MD, NeuroPace chief medical officer and Clinical Professor of Neurology at Stanford University. “The results of the pivotal study clearly demonstrate that the safety and efficacy of the RNS System is sustained over two years. Additional data about safety and efficacy beyond two years is being collected in a long-term follow-up study.”

The pivotal trial primary safety endpoint was met by demonstrating a serious adverse event rate for the first 4 and 12 weeks post-implant comparable to similar procedures. There was no difference between the active and sham stimulation groups in the rate of adverse events, including depression, memory impairment and anxiety. There were no serious unanticipated device related adverse events reported in any of the clinical trials . Although there can be no assurances that additional long-term data will not reveal new adverse information presently unknown to NeuroPace, two y ear data shows no increase or worsening of adverse events.

A total of 256 patients have been implanted with the RNS System. At this time, some patients have been treated with the RNS System for over eight years, and more than 1,200 patient years of experience with responsive neurostimulation have been accumulated to date.


The RNS System is the first closed-loop responsive brain stimulation system. The system is designed to treat partial onset seizures by detecting specific types of electrical activity in the brain through leads containing electrodes that are placed near the patient’s seizure focus or foci. When detection thresholds are met, the device delivers small bursts of electrical stimulation intended to reduce the frequency of seizures. Physicians c an program the detection and stimulation parameters of t he implanted RNS Neurostimulator non-invasively to customize therapy for each individual.