Neuro implant developer, NeuroPace has announced the U.S. FDA approval of its RNS Stimulator, a device to help reduce the frequency of seizures in epilepsy patients who have not responded well to medications.
Background
Epileptic seizures happen when clusters of nerve cells in the brain signal abnormally, which may briefly alter a person’s consciousness, movements or actions. According to the Epilepsy Foundation, epilepsy affects nearly 3 million people in the United States and is the third most common neurological disorder, after Alzheimer’s disease and stroke. Approximately 40 percent of people with epilepsy are severely affected and continue to have seizures despite treatment.
NeurPace has developed a device that offers an alternative to drug therapy which often doesn’t work satisfactorily. The company’s RNS Stimulator is a small, implantable device that resides within the skull under the scalp. The neurostimulator is connected to one or two electrodes that are placed where the seizures are suspected to originate within the brain or on the surface of the brain. It works by detecting specific types of electrical activity in the brain, the device delivering small bursts of electrical stimulation intended to reduce the frequency of seizures. Physicians can program the detection and stimulation parameters of the implanted RNS Neurostimulator non-invasively to customize therapy for each individual.
The RNS System’s indicated use is a complicated and rather specific affair at the present time. It is intended to be used as an adjunctive therapy in reducing the frequency of seizures in individuals 18 years of age or older with partial onset seizures who have undergone diagnostic testing that localized no more than two epileptogenic foci. Candidates must be shown to be unresponsive to at least two antiepileptic medications, and currently have frequent and disabling seizures.
The FDA’s approval is supported by a three-month randomized control trial of 191 patients with drug-resistant epilepsy. The study showed that by three months after the implanted device was turned on (active use) patients experienced a nearly 38 percent reduction in the average number of seizures per month, compared to an approximately 17 percent reduction in the average number of seizures per month in patients who had the implanted device turned off. At the end of three months, the median reduction in seizures, which reflects a more typical patient experience, was 34 percent with active use and about 19 percent with the device turned off.
During the trial, 29 percent of patients with an active device experienced at least a 50 percent reduction in the overall number of seizures, compared to 27 percent for those with the implanted device turned off.
Two-year follow-up data demonstrated a persistent reduction in seizure frequency.
FDA Comments
“The neurostimulator detects abnormal electrical activity in the brain and responds by delivering electrical stimulation intended to normalize brain activity before the patient experiences seizure symptoms,” said Christy Foreman, director of the Office of Device Evaluation in the FDA’s Center for Devices and Radiological Health.
Company comments
“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.”
“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 U.S. 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.”
Source: Neuropace, Inc., FDA
published: November 15, 2013 in: Approval/Clearance, Neuro