The Food and Drug Administration has approved the MicroTransponder Vivistim Paired VNS System (Vivistim System) for the treatment of moderate to severe motor deficits of the upper extremities associated with chronic ischemic stroke with vagus nerve stimulation (VNS).
The Vivistim System has an Implantable Pulse Generator (IPG) that is placed under the skin in the patient’s chest and creates a light electrical pulse. A drain wire is attached to the IPG that is implanted under the skin and leads to electrodes placed on the left side of the neck. The VNS system also includes clinician software preinstalled on a laptop and a wireless transmitter. Healthcare providers can enter IPG settings (e.g. amplitude, frequency, pulse width) as well as record the stimulation history and the movements performed.
The approval was based on efficacy and safety data from a randomized, sham-controlled study (ClinicalTrials.gov Identifier: NCT03131960) in 108 patients with moderate to severe arm weakness after at least 9 months after an ischemic stroke. The patients were randomized 1: 1 and received either the Vivistim system or sham stimulation in addition to rehabilitation therapy. The primary efficacy endpoint was the mean change in impairment, measured using the Fugl-Meyer Assessment Upper Extremity (FMA-UE) score.
The results showed that patients in the Vivistim system group achieved an average score increase of 5 points compared to 2.4 points in the control group (difference 2.6; 95% CI 1.0-4.2; P = 0.0014). In addition, 47.2% of the patients in the Vivistim System group showed an improvement in the FMA-UE score of at least 6 points 90 days after therapy compared to 23.6% of the patients in the control group.
In terms of safety, side effects included dysphonia, bruising, falls, general hoarseness, general pain, hoarseness after surgery, bad mood, muscle pain, fracture, headache, rash, dizziness, throat irritation, urinary tract infection, and fatigue. The Vivistim System should not be used in patients who have had a vagotomy.
“Today’s approval of Vivistim’s paired VNS system provides the first option for stroke rehabilitation with vagus nerve stimulation,” said Christopher M. Loftus, MD, associate director of the FDA’s Center for Devices and Radiological Health for neurological and physical medical devices. “In conjunction with rehabilitation exercises, this device can benefit those who have lost the function of their upper limbs due to an ischemic stroke.”
The Vivistim System is a prescription device that can be used in both the clinic and at home. For home rehabilitation, patients must be trained in the use of the Vivistim system at home.
- FDA approves first stroke rehabilitation system of its kind. Press release. U.S. Food and Drug Administration. Accessed August 27, 2021. https://www.prnewswire.com/news-releases/fda-approves-first-of-its-kind-stroke-rehabilitation-system-301364373.html.
- Dawson J, Liu CY, Francisco GE et al. Vagus nerve stimulation paired with rehabilitation of motor function of the upper limbs after ischemic stroke (VNS-REHAB): a randomized, blinded, approval-relevant device study. The lancet. Published online April 24, 2021. doi.org/10.1016/S0140-6736(21)00475-X.
This article originally appeared on MPR