Trial Review

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Trial details imported from ClinicalTrials.gov

For full trial details, please see the original record at https://clinicaltrials.gov/ct2/show/NCT06016686




Registration number
NCT06016686
Ethics application status
Date submitted
10/07/2023
Date registered
30/08/2023
Date last updated
3/05/2024

Titles & IDs
Public title
Microelectrode Recordings From the Vagus Nerve in Awake Humans
Scientific title
Microelectrode Recordings From the Vagus Nerve in Awake Humans
Secondary ID [1] 0 0
VNS
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Epilepsy 0 0
Condition category
Condition code
Neurological 0 0 0 0
Epilepsy

Intervention/exposure
Study type
Interventional
Description of intervention(s) / exposure
Other interventions - VNS stimulation and intraneural recordings
Other interventions - Record multi-unit activity from intraneural sites

Experimental: VNS - participants with surgically implanted VNS electrodes to treat drug-resistant epilepsy

Experimental: non-VNS participants - participants without implanted VNS devices


Other interventions: VNS stimulation and intraneural recordings
A minimum of three stimulation frequencies (1, 10 and 30 Hz), each up to 60s in duration, will be delivered via the VNS device. Intraneural recordings proximal or distal to the VNS electrodes during delivery of VNS will be performed. Approximately two to five fascicles will be explored in each nerve.

Other interventions: Record multi-unit activity from intraneural sites
Perform a more detailed vagal nerve mapping study by recording from single nerve fibers, including those fibers supplying the heart, lungs, airways and other end-organs. The investigators shall perform functional mapping of the left and right vagus nerves, such as those with cardiac-related and/or respiratory-related neural activity. The research team will also record activity from other nearby fibers to map the differences in neurological behavior in fascicles that control the heart, lungs, airways and other systems.
Intervention code [1] 0 0
Other interventions
Comparator / control treatment
Control group

Outcomes
Primary outcome [1] 0 0
identify action potential morphology of specific fibers activated by vagal nerve stimulation (VNS)
Timepoint [1] 0 0
4 hours
Primary outcome [2] 0 0
identify ratio of myelinated fibers in specific fibers activated by vagal nerve stimulation (VNS)
Timepoint [2] 0 0
4 hours
Primary outcome [3] 0 0
physiological identification of the specific fibers activated by vagal nerve stimulation (VNS)
Timepoint [3] 0 0
4 hours
Primary outcome [4] 0 0
identify firing rates of the specific fibers activated by vagal nerve stimulation (VNS)
Timepoint [4] 0 0
4 hours
Primary outcome [5] 0 0
identify stimulus current required to activate specific fibers activated by vagal nerve stimulation (VNS)
Timepoint [5] 0 0
4 hours
Primary outcome [6] 0 0
differences in firing rates of cardiac parasympathetic vagal activity
Timepoint [6] 0 0
4 hours
Primary outcome [7] 0 0
Discharge variability of cardiac parasympathetic nerve fibers
Timepoint [7] 0 0
4 hours

Eligibility
Key inclusion criteria
- The participant is greater than or equal to (=)18 years and is less than or equal to
(=) 40 years of age

- English speaking

- Medicare covered or equivalent health insurance from a partner country
Minimum age
18 Years
Maximum age
40 Years
Sex
Both males and females
Can healthy volunteers participate?
Yes
Key exclusion criteria
- Pregnant

- Smokes and is unwilling to abstain from smoking on the day of the experiment.

- Inability or unwillingness to provide written informed consent.

- Individuals with difficulty standing unassisted for 5 minutes during the tilt-table
testing

- Individuals found to have a significant carotid artery plaque or intima-media
thickness > 1 mm as assessed by ultrasonography during the ultrasound-screening steps
of the study visit

- Vagus nerve not visible on ultrasound

- VNS electrodes are not in a suitable location to allow for microelectrode insertion

- Any other clinical reasons deemed by the investigators

Study design
Purpose of the study
Supportive Care
Allocation to intervention
Non-randomised trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Masking / blinding
Open (masking not used)
Who is / are masked / blinded?



Intervention assignment
Parallel
Other design features
Phase
Phase 1
Type of endpoint/s
Statistical methods / analysis

Recruitment
Recruitment status
Recruiting
Data analysis
Reason for early stopping/withdrawal
Other reasons
Date of first participant enrolment
Anticipated
Actual
1/04/2024
Date of last participant enrolment
Anticipated
Actual
Date of last data collection
Anticipated
1/04/2025
Actual
Sample size
Target
60
Accrual to date
Final
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 0 0
99 Commercial Road - Prahan Victoria
Recruitment postcode(s) [1] 0 0
3182 - Prahan Victoria
Recruitment outside Australia
Country [1] 0 0
United States of America
State/province [1] 0 0
Minnesota

Funding & Sponsors
Primary sponsor type
Other
Name
University of Minnesota
Address
Country

Ethics approval
Ethics application status

Summary
Brief summary
This Anchillary project uses a refined technique of ultrasound-guided microneurography of the
human cervical vagus nerve, an approach developed by Professor Vaughan Macefield and used
safely to-date in 44 prior study participants.

The overall goal of this project is to build upon prior data obtained using this approach by
undertaking a detailed neurophysiological investigation of the human vagus nerve and to
identify the nerve fibers activated during vagal nerve stimulation (VNS) in participants with
implanted VNS devices in response to different stimulation parameters. In addition to
providing data in unprecedented detail into the physiology of the human vagus nerve, this
project will investigate different stimulus intensities, durations and frequencies that
differentially excite myelinated and unmyelinated nerve fibers. These results will inform the
CSP and guide future development of novel neural interfaces for VNS for various clinical
applications.
Trial website
https://clinicaltrials.gov/ct2/show/NCT06016686
Trial related presentations / publications
Public notes

Contacts
Principal investigator
Name 0 0
Vaughan G Macefield, PhD
Address 0 0
Monash University
Country 0 0
Phone 0 0
Fax 0 0
Email 0 0
Contact person for public queries
Name 0 0
Kathryn Vera, PhD
Address 0 0
Country 0 0
Phone 0 0
612-625-5018
Fax 0 0
Email 0 0
giero002@umn.edu
Contact person for scientific queries



Summary Results

For IPD and results data, please see https://clinicaltrials.gov/ct2/show/NCT06016686