NeuroPace, Inc. today announced that it has submitted its Premarket Approval (PMA) application to the U.S. Food and Drug Administration (FDA) for its RNS® System, a novel investigational device that utilizes responsive neurostimulation to monitor and interrupt abnormal electrical activity in the brain before seizures occur. The PMA application is for an indication to treat people with medically refractory partial onset epilepsy originating from one or two locations in the brain. Partial onset epilepsy is a common form of the disorder that is difficult to treat with medication. Results from the company's pivotal trial were included in the PMA application. The data, some of which were presented at the American Epilepsy Society's (AES) 63rd Annual Meeting in December 2009, were collected from 191 people with medically refractory partial onset epilepsy enrolled at 31 sites located in the United States. The results demonstrate the RNS System significantly reduced the frequency of disabling seizures.
"The clinical data support that this unique technology can provide an effective method to significantly reduce seizure frequency with a positive safety profile for people with partial onset epilepsy," said David Roberts, MD, Chief of Neurosurgery at Dartmouth-Hitchcock Medical Center. "Epilepsy is an extremely challenging disorder to treat and despite our best efforts, there is a large population of people who do not respond well to the currently available treatment options. The RNS System has the potential to meaningfully improve quality of life for many people who are currently living with uncontrollable seizures."
The RNS System continuously monitors brain electrical activity and, after identifying a preprogrammed abnormal pattern, delivers brief and mild electrical stimulation with the intention of suppressing the seizure before symptoms occur.
"The RNS System is the world's first responsive neurostimulation system," said Frank Fischer, CEO of NeuroPace. "We look forward to working with the FDA during the review process, and firmly believe the RNS System has the potential to provide an invaluable additional treatment option for people living with epilepsy."
The pivotal trial is a randomized, double-blind, sham stimulation controlled investigation of patients with partial onset epilepsy that previously had failed to achieve seizure control with two or more antiepileptic drugs. The primary effectiveness endpoint was to demonstrate a significantly greater reduction in seizure frequency in the treatment group (responsive stimulation on) compared to the sham stimulation group (responsive stimulation off) during the three month blinded evaluation period. Based on the statistical method prespecified in the clinical protocol (general estimating equations (GEE)), the reduction in seizure frequency over the blinded evaluation period was 37.9 percent in the treatment group compared to a 17.3 percent reduction in the sham stimulation group. This was statistically significant with a P value of 0.012. Also based on the GEE method, the treatment group experienced a 41.5 percent reduction in seizure frequency compared to only a 9.4 percent reduction in the sham group by the third month of the blinded evaluation period. For those subjects who had already reached two years post-implant, 53 percent experienced a 50 percent or greater reduction in seizures.
Importantly, the reduction in seizures with responsive stimulation was clinically meaningful as demonstrated by significant improvements in quality of life. At one and two years after implant, there were statistically significant improvements not only in overall quality of life but also in a number of subsets of quality of life including language, memory, attention/concentration, work/drive/social function, seizure worry and health discouragement.
The trial also demonstrated a serious adverse event rate less than comparative surgical procedures. There were no serious unanticipated device related adverse events reported in the trial, and there was no difference between the treatment and sham stimulation groups when comparing the rate of adverse events, including depression, memory impairment and anxiety.