MicroTransponder Inc., today announced that the pivotal clinical trial results for the Company’s investigational Vivistim® Paired Vagus Nerve Stimulation (VNS) System have been published in The Lancet.
Each year in the US, 50-60% of the 658,000 stroke survivors have upper extremity motor deficits that persist for many months to years after their stroke. The Lancet reports that patients receiving Vivistim® Paired VNS™ System therapy showed 2-3 times the improvement in upper extremity motor impairment and function compared to controls that received intense rehabilitation alone.
The multi-center, double-blinded, randomized controlled trial enrolled 108 subjects that were up to 10 years post-stroke with moderate to severe upper extremity impairment. Subjects in the study were randomized to either the Paired VNS group (intense physical therapy paired with active VNS) or Control group (intense physical therapy paired with sham VNS) and did 6 weeks of in-clinic therapy followed by 3 months of home-based therapy. After in-clinic therapy, subjects in the Paired VNS group showed a 5.0 point improvement in the Upper Extremity Fugl-Meyer Assessment compared to 2.4 points in controls (p=0.001).
The Wolf Motor Function Test score also improved after Paired VNS compared to controls (0.46 vs 0.16, p<0.0001). After 3 months of home-based therapy, the number of participants achieving a clinically meaningful response in upper limb impairment after Paired VNS was approximately twice that of controls. The study showed that participants who received Paired VNS had clinically meaningful improvements in both motor impairment and function compared to controls. Improvements with Paired VNS™ were also observed in quality-of-life measures. There were no unexpected adverse events or serious adverse events associated with the Vivistim® System.
“This is the first study to find clinically- and statistically-significant effects of a neuromodulation therapy for people with arm and hand weakness after a chronic stroke,” Dr. Jesse Dawson, Professor of Stroke Medicine, at the University of Glasgow remarks “We saw improvement for the VNS group in both impairment and functional measures compared to Controls. In particular, the clinically meaningful response rate doubled with paired VNS for both impairment and functional outcomes.”
“The results of this clinical study suggest that the addition of VNS enhances the effect of best practice stroke rehabilitation. It is also important to note that our physical and occupational therapists were able to easily incorporate the Vivistim® System with intense rehabilitation therapy.” stated Dr. Teresa Kimberley, PhD, PT, Professor and Director of the Brain Recovery Lab at MGH Institute of Health Professions.
The safety of VNS implants has been well established in other clinical areas. Dr. Charles Liu, PhD, MD, Chair of Neurosurgery, Chief of Innovation & Research at Rancho Los Amigos and Director of the USC Neurorestoration Center, Keck Medicine of USC commented, “VNS implant procedures have been performed for over 20 years and are generally simple and straightforward. We’re excited by the prospect of safe and established surgical procedures that may help restore hand and arm function after stroke.”
Dr. Steve Cramer, Professor of Neurology at UCLA and Medical Director of Research at California Rehabilitation Institute in Los Angeles, observed, “Patients with chronic stroke have limited options for therapy, so it is encouraging to see these positive results in stroke patients up to 10 years post-stroke”.
“The long-term multiplicative benefits of VNS over control therapy across different outcome measures observed in this study suggest that this may be an effective long-term therapeutic intervention for chronic stroke patients” noted Steven L. Wolf, PT, Ph.D., Professor and Director of Research in the Department of Rehabilitation Medicine, Division of Physical Therapy, Emory University School of Medicine.
The Vivistim® Paired VNS™ System stimulates the vagus nerve during task-specific rehabilitation. Stimulation of the vagus nerve triggers release of brain neuromodulators including acetylcholine and norepinephrine that strengthen motor circuits associated with movement, enabling the brain to effectively relearn the task.
Efforts to obtain marketing authorizations from regulatory authorities in both the U.S. and the EU are currently underway advises MicroTransponder.
Dawson J et al, Vagus Nerve Stimulation Paired with Rehabilitation for Upper Limb Motor Function After Ischaemic Stroke (VNS-REHAB): A Randomised, Blinded, Pivotal, Device Trial The Lancet, Vol 397, April 24, 2021
LANCET ARTICLE IS AVAILABLE ONLINE: https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(21)00475-X/fulltext
EDITORIAL: van der Meij A, Vagus Nerve Stimulation: a Potential New Treatment for Ischaemic Stroke The Lancet, Vol 397, April 24, 2021