Vagal Nerve Stimulation to Treat Disorders of Consciousness

NCT ID: NCT07077135

Last Updated: 2025-07-22

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

Get a concise snapshot of the trial, including recruitment status, study phase, enrollment targets, and key timeline milestones.

Recruitment Status

NOT_YET_RECRUITING

Clinical Phase

NA

Total Enrollment

106 participants

Study Classification

INTERVENTIONAL

Study Start Date

2025-09-01

Study Completion Date

2028-09-01

Brief Summary

Review the sponsor-provided synopsis that highlights what the study is about and why it is being conducted.

This interventional study aims to assess the clinical efficacy of transcutaneous auricular vagal nerve stimulation (taVNS) against sham stimulation on the recovery of consciousness in patients with disorders of consciousness. The main question it aims to answer is: will taVNS improve patients' behavioral scores or will it produce an improvement in the diagnosed level of consciousness? Researchers will compare the results with non-stimulated unconscious patients to see if the re-gain of consciousness is faster in the treated group.

Participants will undergo taVNS stimulation using the Parasym device or sham stimulation will be applied from the time of enrolment.

Active stimulations will be carried out for 60 minutes twice daily during the acute phase and daily during the rehabilitation phase.

Detailed Description

Dive into the extended narrative that explains the scientific background, objectives, and procedures in greater depth.

This is a prospective, multicentric, double-blind, parallel, 2 arms, randomized controlled trial that compares active taVNS stimulation against sham stimulation.

The primary objective of this study is to assess the clinical efficacy of transcutaneous auricular vagal nerve stimulation (taVNS) against sham stimulation on the recovery of consciousness in patients with disorders of consciousness (DoC), including comatose patients, unresponsive wakefulness syndrome (UWS) or minimally conscious state (MCS). The hypothesis is that taVNS will improve patients' behavioral scores compared to sham stimulation, as measured by an improvement of at least 3 points in the Coma Recovery Scale-Revised score (CRS-R) or an improvement in the diagnosed level of consciousness, measured at 3 months post-randomization, coinciding with the end of stimulation.

As a secondary objective, we will investigate whether:

1. taVNS is effective in achieving a faster time to recovery of consciousness in DoC patients compared to controls;
2. the CRS-R score differs in the two groups at 3 and 6 months post-randomization;
3. the persistence of improvements in the treated group also at 6 months post-randomization.

taVNS stimulation using the Parasym device or sham stimulation will be applied from the time of enrolment (between 7 to 15 days since admission in ICU) un-til day 90 post-enrolment.

Active stimulations will be carried out daily for 60 minutes twice daily during the acute phase and daily during the rehabilitation phase The stimulation waveform includes trains of pulses with widths of 200 µs and repetition rate of 20 Hz (Nurosym proprietary waveform); current delivery will be set at a prede-fined therapeutic level below 0.25 W/cm² (Watts per centimeter squared), that being the defined risk threshold for a thermal burn. The device adjusts stimulation intensity at 0.8 mA steps; the starting intensity will be set at 16 mA (level 20).

Assuming a delta of response of 30% at 3 months between the experimental and the sham group and considering a 1:1 randomization ratio and a 20% drop-out rate, a sample of 53 patients per group (106 in total) is required to reach a power of 80% (alpha=5% and two-sided test on proportion).

Conditions

See the medical conditions and disease areas that this research is targeting or investigating.

Disorder of Consciousness

Study Design

Understand how the trial is structured, including allocation methods, masking strategies, primary purpose, and other design elements.

Allocation Method

RANDOMIZED

Intervention Model

PARALLEL

Primary Study Purpose

TREATMENT

Blinding Strategy

QUADRUPLE

Participants Caregivers Investigators Outcome Assessors

Study Groups

Review each arm or cohort in the study, along with the interventions and objectives associated with them.

Stimulated group

taVNS stimulation using the Parasym device or sham stimulation will be applied from the time of enrolment (between 7 to 15 days since admission in ICU) until day 90 post-enrolment. Active stimulations will be carried out daily for 60 minutes twice daily during the acute phase and daily during the rehabilitation phase The stimulation waveform includes trains of pulses with widths of 200 µs and repetition rate of 20 Hz (Nurosym proprietary waveform); current delivery will be set at a predefined therapeutic level below 0.25 W/cm² (Watts per centimeter squared), that being the defined risk threshold for a thermal burn. The device adjusts stimulation intensity at 0.8 mA steps; the starting intensity will be set at 16 mA (level 20).

Group Type EXPERIMENTAL

stimulated group

Intervention Type DEVICE

Participants will be randomly assigned to receive either taVNS applied to the tragus of the ear or a sham stimulation from the time of randomization for 90 days. Active simulations will be carried out daily using the Parasym device for 60 minutes twice daily during the acute phase (two sessions, one in the morning and one in the afternoon), and once daily (single session) during the rehabilitation phase. The stimulation waveform includes trains of pulses with widths of 200 µs and repetition rate of 20 Hz (Nurosym proprietary waveform); current delivery will be set at a predefined therapeutic level below 0.25 W/cm² (Watts per centimeter squared), that being the defined risk threshold for a thermal burn. The device adjusts stimulation intensity at 0.8 mA steps; the starting intensity will be set at 16 mA (level 20).

Control group

The Parasym device will be positioned on the patients as for the stimulated group (60 minutes twice daily during the acute phase - two sessions, one in the morning and one in the afternoon), and once daily (single session) during the rehabilitation phase but it won't be switched on.

Group Type SHAM_COMPARATOR

Sham (No Treatment)

Intervention Type DEVICE

The sham stimulation involves placing the electrode on the same site without delivering any electrical current. The device will be applied to the tragus without electrical current delivered from the time of randomization for 90 days (i.e., the time of randomization coincides with the first stimulation session).

Interventions

Learn about the drugs, procedures, or behavioral strategies being tested and how they are applied within this trial.

stimulated group

Participants will be randomly assigned to receive either taVNS applied to the tragus of the ear or a sham stimulation from the time of randomization for 90 days. Active simulations will be carried out daily using the Parasym device for 60 minutes twice daily during the acute phase (two sessions, one in the morning and one in the afternoon), and once daily (single session) during the rehabilitation phase. The stimulation waveform includes trains of pulses with widths of 200 µs and repetition rate of 20 Hz (Nurosym proprietary waveform); current delivery will be set at a predefined therapeutic level below 0.25 W/cm² (Watts per centimeter squared), that being the defined risk threshold for a thermal burn. The device adjusts stimulation intensity at 0.8 mA steps; the starting intensity will be set at 16 mA (level 20).

Intervention Type DEVICE

Sham (No Treatment)

The sham stimulation involves placing the electrode on the same site without delivering any electrical current. The device will be applied to the tragus without electrical current delivered from the time of randomization for 90 days (i.e., the time of randomization coincides with the first stimulation session).

Intervention Type DEVICE

Other Intervention Names

Discover alternative or legacy names that may be used to describe the listed interventions across different sources.

experimental arm control group

Eligibility Criteria

Check the participation requirements, including inclusion and exclusion rules, age limits, and whether healthy volunteers are accepted.

Inclusion Criteria

* Age ≥ 18 years old;
* any acquired cerebral damage of any known etiology;
* diagnosis of coma, UWS, or MCS with the corresponding basal CRS-R (Coma Recovery Scale-Revised) score performed during the screening period from 7 to 15 days since admission in ICU;
* intact ear skin;
* availability of the device.

Exclusion Criteria

* Patients with severe hemodynamic, respiratory, infectious, or neurological instability requiring active treatment requiring mechanical ventilation or vasoactive drugs or pending acute neurosurgical interventions;
* Need for deep sedation, including general anesthetics (e.g., propofol) or a combination of central-acting sedatives;
* Documented pregnancy;
* Active implant (e.g., pacemaker, cochlear implant);
* History of previous serious neurological disability before the brain injury;
* Seizures or status epilepticus as cause sustaining the disorder of consciousness;
* Patients already enrolled in another ongoing interventional trial.
Minimum Eligible Age

18 Years

Eligible Sex

ALL

Accepts Healthy Volunteers

No

Sponsors

Meet the organizations funding or collaborating on the study and learn about their roles.

Fondazione IRCCS San Gerardo dei Tintori

OTHER

Sponsor Role lead

Responsible Party

Identify the individual or organization who holds primary responsibility for the study information submitted to regulators.

Responsibility Role SPONSOR

Principal Investigators

Learn about the lead researchers overseeing the trial and their institutional affiliations.

Giuseppe Citerio, MD, Full Professor

Role: PRINCIPAL_INVESTIGATOR

University of Milano-Bicocca / Fondazione IRCCS San Gerardo dei Tintori

Alberto Addis, MD

Role: STUDY_DIRECTOR

Fondazione IRCCS San Gerardo dei Tintori

Locations

Explore where the study is taking place and check the recruitment status at each participating site.

ASST degli Spedali Civili di Brescia

Brescia, BS, Italy

Site Status

Fondazione IRCCS San Gerardo dei Tintori

Monza, MB, Italy

Site Status

ASST Papa Giovanni XXIII

Bergamo, , Italy

Site Status

ASST Lariana Ospedale S. Anna

Como, , Italy

Site Status

Ospedale Policlinico San Martino IRCCS

Genova, , Italy

Site Status

ASST Grande Ospedale Metropolitano Niguarda

Milan, , Italy

Site Status

Azienda Ospedaliera Università di Padova

Padua, , Italy

Site Status

Azienda Ospedaliera Universitaria di Parma

Parma, , Italy

Site Status

Fondazione Policlinico Universitario Agostino Gemelli IRCCS

Roma, , Italy

Site Status

Humanitas Research Hospital

Rozzano, , Italy

Site Status

ASST Sette Laghi Ospedale di Circolo e Fondazione Macchi

Varese, , Italy

Site Status

Countries

Review the countries where the study has at least one active or historical site.

Italy

Central Contacts

Reach out to these primary contacts for questions about participation or study logistics.

Giuseppe Citerio, MD, Full Professor

Role: CONTACT

+390392334316

Facility Contacts

Find local site contact details for specific facilities participating in the trial.

Francesco Rasulo, MD, Professor

Role: primary

Alberto Addis, MD

Role: primary

+390392334335

Paolo Gritti, MD

Role: primary

Simone M Zerbi, MD

Role: primary

Chiara Robba, MD, Professor

Role: primary

Arturo Chieregato, MD

Role: primary

Marina Munari, MD

Role: primary

Edoardo Picetti, MD

Role: primary

Anselmo Caricato, MD, Professor

Role: primary

Federico Villa, MD

Role: primary

Luca Cabrini, MD

Role: primary

References

Explore related publications, articles, or registry entries linked to this study.

Sanz LRD, Laureys S, Gosseries O. Towards modern post-coma care based on neuroscientific evidence. Int J Clin Health Psychol. 2023 Jul-Sep;23(3):100370. doi: 10.1016/j.ijchp.2023.100370. Epub 2023 Feb 3.

Reference Type RESULT
PMID: 36817874 (View on PubMed)

Vitello MM, Briand MM, Ledoux D, Annen J, El Tahry R, Laureys S, Martin D, Gosseries O, Thibaut A. Transcutaneous vagal nerve stimulation to treat disorders of consciousness: Protocol for a double-blind randomized controlled trial. Int J Clin Health Psychol. 2023 Apr-Jun;23(2):100360. doi: 10.1016/j.ijchp.2022.100360. Epub 2022 Nov 29.

Reference Type RESULT
PMID: 36467262 (View on PubMed)

Urbin MA, Lafe CW, Simpson TW, Wittenberg GF, Chandrasekaran B, Weber DJ. Electrical stimulation of the external ear acutely activates noradrenergic mechanisms in humans. Brain Stimul. 2021 Jul-Aug;14(4):990-1001. doi: 10.1016/j.brs.2021.06.002. Epub 2021 Jun 18.

Reference Type RESULT
PMID: 34154980 (View on PubMed)

Briand MM, Gosseries O, Staumont B, Laureys S, Thibaut A. Transcutaneous Auricular Vagal Nerve Stimulation and Disorders of Consciousness: A Hypothesis for Mechanisms of Action. Front Neurol. 2020 Aug 25;11:933. doi: 10.3389/fneur.2020.00933. eCollection 2020.

Reference Type RESULT
PMID: 32982941 (View on PubMed)

Sharon O, Fahoum F, Nir Y. Transcutaneous Vagus Nerve Stimulation in Humans Induces Pupil Dilation and Attenuates Alpha Oscillations. J Neurosci. 2021 Jan 13;41(2):320-330. doi: 10.1523/JNEUROSCI.1361-20.2020. Epub 2020 Nov 19.

Reference Type RESULT
PMID: 33214317 (View on PubMed)

Gerges ANH, Williams EER, Hillier S, Uy J, Hamilton T, Chamberlain S, Hordacre B. Clinical application of transcutaneous auricular vagus nerve stimulation: a scoping review. Disabil Rehabil. 2024 Dec;46(24):5730-5760. doi: 10.1080/09638288.2024.2313123. Epub 2024 Feb 16.

Reference Type RESULT
PMID: 38362860 (View on PubMed)

Wu X, Xie L, Lei J, Yao J, Li J, Ruan L, Hong J, Zheng G, Cheng Y, Long L, Wang J, Huang C, Xie Q, Zhang X, He J, Yu X, Lv S, Sun Z, Liu D, Li X, Zhu J, Yang X, Wang D, Bao Y, Maas AIR, Menon D, Xue Y, Jiang J, Feng J, Gao G; ACES Participants. Acute traumatic coma awakening by right median nerve electrical stimulation: a randomised controlled trial. Intensive Care Med. 2023 Jun;49(6):633-644. doi: 10.1007/s00134-023-07072-1. Epub 2023 May 13.

Reference Type RESULT
PMID: 37178149 (View on PubMed)

Schiff ND. Recovery of consciousness after brain injury: a mesocircuit hypothesis. Trends Neurosci. 2010 Jan;33(1):1-9. doi: 10.1016/j.tins.2009.11.002. Epub 2009 Dec 1.

Reference Type RESULT
PMID: 19954851 (View on PubMed)

Manta S, Dong J, Debonnel G, Blier P. Optimization of vagus nerve stimulation parameters using the firing activity of serotonin neurons in the rat dorsal raphe. Eur Neuropsychopharmacol. 2009 Apr;19(4):250-5. doi: 10.1016/j.euroneuro.2008.12.001. Epub 2009 Jan 15.

Reference Type RESULT
PMID: 19150228 (View on PubMed)

Sandroni C, Citerio G, Taccone FS. Automated pupillometry in intensive care. Intensive Care Med. 2022 Oct;48(10):1467-1470. doi: 10.1007/s00134-022-06772-4. Epub 2022 Jun 30. No abstract available.

Reference Type RESULT
PMID: 35773500 (View on PubMed)

Giacino JT, Katz DI, Schiff ND, Whyte J, Ashman EJ, Ashwal S, Barbano R, Hammond FM, Laureys S, Ling GSF, Nakase-Richardson R, Seel RT, Yablon S, Getchius TSD, Gronseth GS, Armstrong MJ. Practice Guideline Update Recommendations Summary: Disorders of Consciousness: Report of the Guideline Development, Dissemination, and Implementation Subcommittee of the American Academy of Neurology; the American Congress of Rehabilitation Medicine; and the National Institute on Disability, Independent Living, and Rehabilitation Research. Arch Phys Med Rehabil. 2018 Sep;99(9):1699-1709. doi: 10.1016/j.apmr.2018.07.001. Epub 2018 Aug 8.

Reference Type RESULT
PMID: 30098791 (View on PubMed)

Other Identifiers

Review additional registry numbers or institutional identifiers associated with this trial.

REVELATION

Identifier Type: -

Identifier Source: org_study_id

More Related Trials

Additional clinical trials that may be relevant based on similarity analysis.

Post-stroke Pain taVNS
NCT06456385 COMPLETED NA
taVNS Cold Pressor
NCT05254080 COMPLETED NA