Transcutaneous Auricular Vagus Nerve Stimulation as a Treatment for Neuropathic Pain Following Spinal Cord Injury

London Health Sciences Centre Research Institute OR Lawson Research Institute of St. Joseph's

Status: Begins enrollment in 3 months

Conditions: Neuropathic Pain; Spinal Cord Injury

Treatments: Device: Sham Transcutaneous Auricular Vagus Nerve Stimulation; Device: Active Transcutaneous Auricular Vagus Nerve Stimulation

Study type: Interventional

Funder types: Other

Identifiers

NCT07588711

ALLISON-03-2026

Details and patient eligibility

About

This pilot randomized, double-blind, sham-controlled clinical investigation will evaluate the feasibility and safety of a 30-day home-based transcutaneous auricular vagus nerve stimulation (taVNS) intervention in adults with spinal cord injury (SCI) and neuropathic pain. Participants will be randomized to receive either active taVNS targeting the auricular branch of the vagus nerve or sham taVNS delivered to the earlobe. Primary outcomes include feasibility, safety, adherence, acceptability, and blinding success. Exploratory outcomes include changes in neuropathic pain, systemic inflammatory biomarkers, vagal tone assessed via heart rate variability, and quality of life.

Full description

Neuropathic pain is a common and debilitating complication following spinal cord injury (SCI) and is frequently resistant to pharmacologic treatment. Chronic neuroinflammation and reduced vagal tone are increasingly recognized contributors to persistent neuropathic pain after SCI. The vagus nerve plays a central role in immune regulation and descending pain modulation.

Transcutaneous auricular vagus nerve stimulation (taVNS) is a noninvasive neuromodulation technique that stimulates vagal afferent fibers via the external ear. Prior Health Canada-authorized trials conducted by the investigative team have demonstrated the feasibility, safety, and autonomic effects of taVNS in individuals with SCI.

This single-site, randomized, double-blind, sham-controlled pilot study will enroll 32 adults with SCI and neuropathic pain. Participants will be randomized 1:1 to receive either active or sham taVNS for 4 hours per day over a 30-day home-based intervention period. Outcomes will be assessed at baseline and immediately post-intervention. Feasibility and safety outcomes are primary, while exploratory clinical and mechanistic outcomes will inform the design of a future definitive randomized controlled trial.

Enrollment: 32 estimated patients

Sex: All

Ages: 18+ years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• SCI of any level or severity
• 18 years of age or older
• current neuropathic pain
• on no medications or on a stable prescribed dose (no change in prior 6-weeks) of anti-inflammatory, pain medications and/or depression medications

Exclusion criteria

• Prone to autonomic dysreflexia
• presence of cardiovascular disease
• pacemaker or other implanted electrical device
• cerebral shunts
• epilepsy
• pregnant or attempting to become pregnant
• current wound/infection
• unstable dose of prescribed anti-inflammatory, depression, or pain medications within past 6-weeks.

Trial design

Primary purpose: Treatment

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: Quadruple Blind

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32 participants in 2 patient groups

Active taVNS

Experimental group

Description:

Participants receive active transcutaneous auricular vagus nerve stimulation delivered via the cymba conchae of the left ear using the using the tVNS R device (taVNS Technologies, Erlangen, Germany) for 4 hours per day for 30 days.

Treatment:

Device: Active Transcutaneous Auricular Vagus Nerve Stimulation

Sham taVNS

Sham Comparator group

Description:

Stimulation will target the ear lobe using the tVNS R device (taVNS Technologies, Erlangen, Germany) for 4 hours per day for 30 days. Stimulation will be applied to the ear lobe in order to ensure participant feel the stimulation while avoiding activation of the vagus nerve.

Treatment:

Device: Sham Transcutaneous Auricular Vagus Nerve Stimulation