Neuromodulation as an Anti-inflammatory Treatment in SCI

Assessing the Efficacy of Transcutaneous Auricular Vagus Nerve Stimulation as an Anti-inflammatory Treatment Following Spinal Cord Injury

The goal of this single-blinded randomized, controlled trial is to assess the impact of 1-hour of active transcutaneous auricular vagus nerve stimulation (taVNS) vs sham taVNS on serum biomarkers of the inflammatory reflex and inflammation in individuals with spinal cord injury.

The main question it aims to answer is: whether taVNS is a safe and effective anti-inflammatory intervention for individuals with SCI. Participants will perform a single 1-hour bout of the respective taVNS treatment with blood draws prior to treatment, immediately following treatment, and 24 hours following treatment. Changes in biomarkers between the active and sham taVNS conditions will be compared.

Study Overview

• Status: Not yet recruiting
• Conditions: Inflammation; Spinal Cord Injuries
• Intervention / Treatment: Device: Transcutaneous auricular vagus nerve stimulation

Detailed Description

Chronic inflammation is very common among individuals living with spinal cord injury (SCI) and contributes to a number of health complications(1). Drug treatments are available to help reduce inflammation, however, many patients are unresponsive, become resistant or experience adverse effects such as increased risk of infection(2). There is a need for other treatments which reduce inflammation while avoiding harmful side effects.

It is now understood that the nervous systems plays an important role in regulating the immune system and controlling inflammation. The vagus nerve has been shown to be a particularly important part of the nervous system in terms of limiting inflammation. However, SCI causes disruption to the nervous system, including reduced activity of the vagus nerve. This may contribute to excessive inflammation. New technologies have been developed that allow the vagus nerve to be activated by electrically stimulating a part of the ear. This technique called vagus nerve stimulation (VNS) has been shown to help reduce inflammation in numerous populations. However, it has not been assessed in individuals with SCI. This study will assess if stimulating the vagus nerve can be a safe and effective way to reduce inflammation in individuals with SCI.

To assess this, 30 individuals with SCI who agree to participate will be randomly assigned to receive either active VNS treatment or sham treatment (whereby the device will placed in such a way that it does not stimulate the vagus nerve). Participants will not be aware of which group they are in. The study will take place over a 2-day period. On day one, participants will arrive in the morning for a fasted blood draw to assess baseline inflammation. Following the blood draw, participants will receive 1-hour of either the active or sham VNS therapy. Immediately following VNS therapy a second blood draw will be performed. On day 2 participants will be asked to return at the same time of day to complete a final fasted blood draw. This will allow for the assessment of how well the therapy activated 2 key anti-inflammatory pathways controlled by the vagus nerve and resulting changes in inflammation (immediate and 24-hour post).

It is expected that VNS therapy will be well-tolerated, safe and effective at reducing inflammation in individuals with SCI. If this is shown, VNS may prove to be a simple and cost-effective means of reducing chronic inflammation in individuals with SCI and may help to replace and/or reduce the need for other pharmaceutical drugs which are associated with adverse health outcomes.

• Study Type: Interventional
• Enrollment (Anticipated): 30
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years and older (Adult, Older Adult)
• Accepts Healthy Volunteers: No
• Genders Eligible for Study: All

Description

Inclusion Criteria:

• Any level of severity of spinal cord injury
• 18 years of age or older

Exclusion Criteria:

• pregnant or attempting to become pregnant
• people with active implants (e.g. cochlear implant, implanted vagus nerve stimulator, cardiac pacemaker)
• people with cerebral shunts

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Single

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Active taVNS; Stimulation will target the auricular branch of the vagus nerve by applying stimulation to the cymba conchae region of the ear using the NEMOS® taVNS device (taVNS Technologies, Erlangen, Germany). To achieve adequate stimulation while avoiding unpleasant or painful sensations, the stimulation intensity will be gradually increased in increments of 0.1mA until the subjective pain threshold is reached, and then reduced to a stimulus intensity just below the individuals pain threshold (expected range based on prior studies 1 - 3.2mA. Pulse width will be set at 100μs and frequency will be set at 25Hz as performed in a previous protocol in stroke patients. Stimulation will be applied for a duration of 1 hour.	Device: Transcutaneous auricular vagus nerve stimulation; Stimulation will target the auricular branch of the vagus nerve by applying stimulation to the cymba conchae region of the ear using the NEMOS® taVNS device (taVNS Technologies, Erlangen, Germany). To achieve adequate stimulation while avoiding unpleasant or painful sensations, the stimulation intensity will be gradually increased in increments of 0.1mA until the subjective pain threshold is reached, and then reduced to a stimulus intensity just below the individuals pain threshold (expected range based on prior studies 1 - 3.2mA(3). Pulse width will be set at 100μs and frequency will be set at 25Hz as performed in a previous protocol in stroke patients(3). The control group will receive the same stimulation parameters but will have the earpiece placed in the sham position such that stimulation is applied to the earlobe and does not activate the vagus nerve(4).; Other Names: NEMOS® taVNS device
Sham Comparator: Sham taVNS; The control group will receive the same stimulation parameters but will have the earpiece placed in the sham position such that stimulation is applied to the earlobe and does not activate the vagus nerve.	Device: Transcutaneous auricular vagus nerve stimulation; Stimulation will target the auricular branch of the vagus nerve by applying stimulation to the cymba conchae region of the ear using the NEMOS® taVNS device (taVNS Technologies, Erlangen, Germany). To achieve adequate stimulation while avoiding unpleasant or painful sensations, the stimulation intensity will be gradually increased in increments of 0.1mA until the subjective pain threshold is reached, and then reduced to a stimulus intensity just below the individuals pain threshold (expected range based on prior studies 1 - 3.2mA(3). Pulse width will be set at 100μs and frequency will be set at 25Hz as performed in a previous protocol in stroke patients(3). The control group will receive the same stimulation parameters but will have the earpiece placed in the sham position such that stimulation is applied to the earlobe and does not activate the vagus nerve(4).; Other Names: NEMOS® taVNS device

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Change in Serum Biomarkers Immediately Following Intervention	Change in serum concentrations of the pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-1 beta (IL-1β), and interferon-gamma (IFN-y) immediately following intervention. Change in serum concentrations of acetylcholine immediately following intervention will be assessed as an indicator of the activity of the cholinergic anti-inflammatory pathway, and the change in cortisol immediately following intervention will be assessed as an indicator of the activity of the neuro-endo-immune pathway.	Baseline - Immediately Following Intervention
Change in Serum Biomarkers 24-hours Following Intervention	Change in serum concentrations of the pro-inflammatory cytokines tumour necrosis factor-alpha (TNF-alpha), C-reactive protein (CRP), interleukin-6 (IL-6), interleukin-1 beta (IL-1β), and interferon-gamma (IFN-y) 24-hours following intervention. Change in serum concentrations of acetylcholine 24-hours following intervention will be assessed as an indicator of the activity of the cholinergic anti-inflammatory pathway, and the change in cortisol 24-hours following intervention will be assessed as an indicator of the activity of the neuro-endo-immune pathway.	Baseline - 24-hour Post Intervention

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Incidence of Treatment-Emergent Adverse Events During or Immediately Following Intervention	All adverse events which occur during or immediately following the intervention will be recorded during the study visit and compared between the taVNS and sham conditions. A description of the adverse event, number of events, and total number of participants affected will be recorded.	Immediately Following Intervention
Incidence of Treatment-Emergent Adverse Events 24-hours Following Intervention	All adverse events which occur within 24-hours following the intervention will be self-reported by participants and recorded and compared between the taVNS and sham conditions. A description of the adverse event, number of events, and total number of participants affected will be recorded.	24-hour Post intervention
Time required to recruit 30 participants	The success of participant recruitment will be assessed based on the time required to recruit the target 30 participants. Completion of recruitment in under 6-months will be considered successful.	Immediately following 6-month recruitment period
Program Completion Rates	Program completion rates will be assessed by the number of participants who completed the entire 1-hour intervention in its entirety.	Immediately after intervention
Participant Satisfaction with Intervention	Participant satisfaction with the intervention will be assessed via an 11-point visual analog scale (VAS) with scores ranging from 0-10 whereby 0 reflects complete dissatisfaction and 10 reflects complete satisfaction as well as qualitatively via participant feedback.	24-hour Post intervention

Collaborators and Investigators

• Sponsor: Lawson Health Research Institute

Publications and helpful links

General Publications

• Frangos E, Ellrich J, Komisaruk BR. Non-invasive Access to the Vagus Nerve Central Projections via Electrical Stimulation of the External Ear: fMRI Evidence in Humans. Brain Stimul. 2015 May-Jun;8(3):624-36. doi: 10.1016/j.brs.2014.11.018. Epub 2014 Dec 6.
• Redgrave JN, Moore L, Oyekunle T, Ebrahim M, Falidas K, Snowdon N, Ali A, Majid A. Transcutaneous Auricular Vagus Nerve Stimulation with Concurrent Upper Limb Repetitive Task Practice for Poststroke Motor Recovery: A Pilot Study. J Stroke Cerebrovasc Dis. 2018 Jul;27(7):1998-2005. doi: 10.1016/j.jstrokecerebrovasdis.2018.02.056. Epub 2018 Mar 23.
• Allison DJ, Ditor DS. The common inflammatory etiology of depression and cognitive impairment: a therapeutic target. J Neuroinflammation. 2014 Sep 2;11:151. doi: 10.1186/s12974-014-0151-1.
• Tynan A, Brines M, Chavan SS. Control of inflammation using non-invasive neuromodulation: past, present and promise. Int Immunol. 2022 Jan 22;34(2):119-128. doi: 10.1093/intimm/dxab073.

Study record dates

Study Major Dates

• Study Start (Anticipated): April 1, 2023
• Primary Completion (Anticipated): September 1, 2023
• Study Completion (Anticipated): October 1, 2023

Study Registration Dates

• First Submitted: January 13, 2023
• First Submitted That Met QC Criteria: February 14, 2023
• First Posted (Actual): February 15, 2023

Study Record Updates

• Last Update Posted (Actual): February 15, 2023
• Last Update Submitted That Met QC Criteria: February 14, 2023
• Last Verified: February 1, 2023

More Information

Terms related to this study

• Keywords: Vagus Nerve Stimulation
• Additional Relevant MeSH Terms: Pathologic Processes; Central Nervous System Diseases; Nervous System Diseases; Wounds and Injuries; Trauma, Nervous System; Spinal Cord Diseases; Inflammation; Spinal Cord Injuries
• Other Study ID Numbers: 12901

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No