Vagus nerve stimulation shows an unprecedented recovery rate in spinal cord injury

In a new clinical study, researchers at the Texas Biomedical Devices Center (TXBDC) at the University of Texas, Dallas, showed an unprecedented recovery rate for spinal cord injuries.

In this study, published in the prestigious journal Nature on May 21, individuals with incomplete spinal cord injury were safely subjected to a progressive, personalized rehabilitation combination of neck nerve stimulation. This approach, called closed-loop vagus nerve stimulation (CLV), has provided meaningful improvements to arm and hand function in these individuals.

The unprecedented results position UT Dallas scientists to advance pivotal trials – the final hurdle on the path to potential Food and Drug Administration (FDA) approval for slurred nerve stimulation for the treatment of upper extremity disorders due to spinal cord injury.

This approach is based on over a decade of neuroscience and bioengineering efforts by UT Dallas investigators. This treatment uses electrical pulses that are implanted in the neck and sent to the brain via small devices that take time to occur during rehabilitation exercises. Previous research by researchers at UT Dallas demonstrated that stimulating the vagus nerve during physical therapy can lead to stroke damage and lead to improved recovery.

Dr. Michael Kilgard, Professor of Neuroscience at the School of Behavior and Brain Sciences, Margaret Fonde Johnson, and the corresponding authors explained that treating spinal cord injuries with CLV differs from the conditions targeted in previous studies.

In stroke, people who only do treatments can get better, and adding CLV increases the improvement. This study is different. Treatment for spinal cord injuries alone did not help participants at all. ”

Dr. Michael Kilgard, Margaret Fonde Johnson, Professor of Neuroscience in Neuroscience

The trial involved 19 participants with chronic, incomplete cervical spinal cord injuries. Each person received 12 weeks of treatment and played a simple video game, causing certain upper limb movements. The implant was activated with successful movements and had great advantages in the strength of the arms and hands.

“These activities allow patients to regain strength, speed, range of motion and hand function, simplifying daily life,” said Dr. Robert Rennell, a professor of neuroscience, and Dr. Chair, a renowned Chair at Bioengineering, who designed miniaturely implanted CLV devices.

This study served as both phase 1 and phase 2 clinical trials, with randomized placebo control included in the first phase in which nine of the 19 participants were sham-stimulated rather than aggressive treatment during the first 18 treatment sessions, and CLV was received in the latter 18 sessions.

Participants ranged from 21 to 65 years old, and were between 1 year and 45 years old after the examination. Neither of these factors affected the severity of the disorder in people with hand movements, nor the extent of their response to treatment.

“This approach produces results regardless of these factors, which often leads to significant differences in the success rates of other types of treatment,” said Jane Wigginton, PhD, co-director of the UTD’s Center for Clinical and Translation Research and Chief Medical Officer at TXBDC, co-director of Brainhealth’s Center for Clinical Research.

“It’s surprising from a medical perspective,” said Wiggington, who planned clinical interactions and patient protection for the trial.

TXBDC has worked to treat a variety of conditions using CLV over 13 years of research. As a result, the FDA approved vagus nerve stimulation to treat impaired upper limb movements in stroke patients.

Wigginton said the latest results are particularly exciting as they help people who don’t have existing solutions.

“The people in this study are now gaining the ability to do things that make sense to them and affect their lives.”

The latest generation of embedded CLV devices designed by Rennaker is roughly 50 times more than the three-year-old version. It does not prevent patients from receiving MRI, CT scans, or ultrasound.

The key phase 3 trials include 70 participants from multiple US institutions specializing in spinal cord injuries.

Seth Hayes, an associate professor of bioengineering and a well-known professor at Eugene McDermott at the Eric Johnson School of Engineering Computer Science, is involved in the CLV project, dating back to early research.

“Perhaps no one with a spinal cord injury had undergone CLV prior to this study,” he said. “This is the first proof that you can benefit. Now we set up a decision on how to make this optimally effective.”

Hayes warned that it is not a natural conclusion that treatment will reach the patient after the next trial.

“We still have a long way to go. For many reasons, financial, regulatory, scientific and scientific, this could still die from a vine,” he said. “But we positioned ourselves to be successful.”

The research team highlighted the importance of dozens involved in both patients at Baylor University Medical Center and TXBDC partners, Baylor Scott and White Research Institute and rehabilitation work at Baylor Scott and White Research Institute.

“It’s the most intensely working group, the most altruistic group of experts, and it’s very impactful,” Wigginton said.

Noting that even outpatient surgery is complicated for people with mobility disorders, Rennaker said, “These patients said, ‘I put that device in me’ – that’s a big commitment. They deserve to pave the way for others.”

Other co-authors in UTD include Joseph Epperson BS’20, PhD’24 and TXBDC Research Associate. Emmanuel Adefnorrwa, a doctoral student in cognition and neuroscience; Amy Porter MBA’20, Director of Operations. Holle Carey Gallaway MBA’23, TXBDC Research Biomedical Engineer; David Pruitt MS’14, PhD’16.

Kilgard has financial interest in Microtransponder Inc., which sells vagus nerve stimulation therapy for stroke. Rennaker is the founder and CEO of Xnerve, who developed the device used in this study.

The study was funded by a grant (N66001-17-2-4011) from the Department of Defense Advanced Research Projects Agency (DARPA), an agency of the Department of Defense, and a Promoted Translation Program for Wings for Life.