NCT07284732

Brief Summary

Consciousness disorders following severe brain injury refer to a series of disturbances in arousal and cognition secondary to organic brain diseases, including Unresponsive Wakefulness Syndrome (UWS) (also termed Vegetative State, VS) and Minimally Conscious State (MCS). Disorders of consciousness(DoC) is listed in the International Statistical Classification of Diseases and Related Health Problems, though it is not currently recognized as an independent and consistent diagnostic category. According to epidemiological surveys, conservative estimates suggest that 70,000 to 100,000 new cases of DoC are reported annually in China, posing significant challenges for clinical diagnosis and treatment. Accurately assessing DoC, understanding its neurobiological underpinnings, and developing effective rehabilitation strategies remain subjects requiring further investigation through both clinical and basic neuroscience research. Transcutaneous Auricular Vagus Nerve Stimulation (taVNS) is a non-invasive brain stimulation technique that delivers electrical impulses to the auricular branch of the vagus nerve. Substantial evidence indicates that taVNS serves as a therapeutic intervention for various neurological and psychiatric disorders, such as epilepsy, treatment-resistant depression, migraines, and cognitive impairments. As an emerging neurostimulation technique, taVNS has been investigated for its potential to promote the recovery of awareness in patients with DoC. However, clinical evidence remains limited, underscoring the need for further trials to substantiate its efficacy. Developed from traditional implanted Vagus Nerve Stimulation(VNS), taVNS offers high safety and minimal to negligible side effects, presenting a promising therapeutic avenue for patients with severe traumatic brain injury and disorders of consciousness. Methods: This study is a single-arm trial. A total of 20 patients are planned to be enrolled. Each patient will receive taVNS twice daily over a period of 10 consecutive days, totaling 20 sessions. Primary and secondary outcome measures will be assessed at baseline and after the completion of taVNS treatment. The primary efficacy endpoint will be the change in behavioral responses as evaluated by the Coma Recovery Scale-Revised (CRS-R). Additionally, resting-state high-density electroencephalography (EEG) and combined transcranial magnetic stimulation with EEG (TMS-EEG) recordings will be utilized to investigate the neurophysiological correlates of taVNS intervention. Discussion: This study will provide valuable insights to inform the selection of treatment approaches for patients with disorders of consciousness. By employing a pre-post within-subject comparison design, it aims to validate the therapeutic role of Closed-Loop Transcutaneous Auricular Vagus Nerve Stimulation (CL-taVNS) in this patient population.

Trial Health

77
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
20

participants targeted

Target at below P25 for not_applicable

Timeline
13mo left

Started May 2024

Typical duration for not_applicable

Geographic Reach
1 country

1 active site

Status
recruiting

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

Study Progress65%
May 2024May 2027

Study Start

First participant enrolled

May 1, 2024

Completed
1.6 years until next milestone

First Submitted

Initial submission to the registry

December 3, 2025

Completed
13 days until next milestone

First Posted

Study publicly available on registry

December 16, 2025

Completed
5 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

May 1, 2026

Completed
1.1 years until next milestone

Study Completion

Last participant's last visit for all outcomes

May 31, 2027

Expected
Last Updated

March 31, 2026

Status Verified

December 1, 2025

Enrollment Period

2 years

First QC Date

December 3, 2025

Last Update Submit

March 25, 2026

Conditions

Outcome Measures

Primary Outcomes (1)

  • Change from Baseline JKF Coma Recovery Scale-Revised(CRS-R)

    The CRS-R comprises six subscales designed to assess auditory, visual, oromotor, communication,and arousal processes. Each CRS-R subscale score is determined based on the presence or absence of specific behavioral responses to sensory stimuli. The total score ranges from 0 to 23, with higher scores indicating a higher level of consciousness in patients with DoC.

    immediately after 10 days TaVNS session

Secondary Outcomes (2)

  • Change from Baseline Resting-State EEG

    immediately after 10 days TaVNS session

  • Change from Baseline TMS-EEG

    immediately after 10 days TaVNS session

Study Arms (1)

Closed-Loop transcutaneous auricular vagus nerve stimulation

EXPERIMENTAL

Stimulation will be delivered on the left cymba conchae using a silicone electrode

Device: transcutaneous auricular vagus nerve stimulation

Interventions

The stimulation protocol consisted of pulse trains at a frequency of 100 Hz. A total of 400 paired RAVANS pulses were delivered per session. The intervention was administered twice daily for 10 consecutive days, resulting in a total of 20 sessions.

Closed-Loop transcutaneous auricular vagus nerve stimulation

Eligibility Criteria

Age18 Years - 70 Years
Sexall
Healthy VolunteersNo
Age GroupsAdult (18-64), Older Adult (65+)

You may qualify if:

  • Aged 18-70 years, with a disease duration exceeding 28 days but not longer than 1 year.
  • Patients diagnosed with disorders of consciousness (DoC), specifically classified as either vegetative state (VS) or minimally conscious state (MCS) according to the Coma Recovery Scale-Revised (CRS-R) based on international guidelines.
  • No prior history of neuropsychiatric disorders.
  • Absence of contraindications to transcutaneous auricular vagus nerve stimulation (taVNS) or electroencephalography (EEG), and no concurrent use of sedatives or medications that may interfere with cerebral stimulation-including Na⁺ or Ca²⁺ channel blockers or NMDA receptor antagonists.
  • Intact skin at the auricular site.

You may not qualify if:

  • Participation in other trials involving non-invasive or invasive neuromodulation.
  • Uncontrolled epilepsy, defined as seizures occurring within 4 weeks prior to enrollment.
  • Presence of cranial metal implants, pacemakers, craniotomy at the stimulation site, implanted brain devices, or similar conditions.
  • Cardiac arrhythmia or other significant cardiovascular abnormalities;
  • History of respiratory disorders, including dyspnea, asthma, or hyperventilation.
  • History of vasovagal syncope.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Zhujiang Hospital of Southern Medical University

Guangzhou, Guangdong, 510280, China

RECRUITING

MeSH Terms

Conditions

Consciousness Disorders

Condition Hierarchy (Ancestors)

Neurobehavioral ManifestationsNeurologic ManifestationsNervous System DiseasesSigns and SymptomsPathological Conditions, Signs and SymptomsNeurocognitive DisordersMental Disorders

Central Study Contacts

Study Design

Study Type
interventional
Phase
not applicable
Allocation
NA
Masking
NONE
Purpose
TREATMENT
Intervention Model
SINGLE GROUP
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
principal investigator

Study Record Dates

First Submitted

December 3, 2025

First Posted

December 16, 2025

Study Start

May 1, 2024

Primary Completion

May 1, 2026

Study Completion (Estimated)

May 31, 2027

Last Updated

March 31, 2026

Record last verified: 2025-12

Data Sharing

IPD Sharing
Will not share

Locations