NCT07822932 · University of Miami
Auricular Vagus Nerve Stimulation Mechanisms for HIV-Associated Peripheral Neuropathy
What this study is about
This study looks at a non-invasive ear stimulation treatment to better understand nerve pain in people living with HIV. The study aims to assess how the body and nervous system respond to this treatment, including changes in heart function and pain signals. The goal is to learn how future treatments for nerve pain may be improved.
View original scientific description
This study looks at a non-invasive ear stimulation treatment to better understand nerve pain in people living with HIV. The study aims to assess how the body and nervous system respond to this treatment, including changes in heart function and pain signals. The goal is to learn how future treatments for nerve pain may be improved.
Interventions
DEVICE
Transcutaneous Auricular Vagus Nerve Stimulation (AVNS)
Transcutaneous auricular vagus nerve stimulation (taVNS) will be administered at the cymba concha using hydrogel electrodes and a Digitimer DS8R biphasic constant-current stimulator. Participants will receive 90-minute stimulation sessions consisting of monophasic pulses (pulse width: 500 microseconds; frequency: 25 Hz; duty cycle: 50%). Stimulation intensity will be set at 200% of the participant's sensory perception threshold and may be adjusted up to 5 milliamperes (mA) while remaining below the pain threshold.
Primary outcome measures
Change in Short Interval intraCortical Inhibition (SICI)
Time frame: Baseline (Day 0), Post-trial (Day 14)
Short-interval intracortical inhibition (SICI) will be assessed using paired-pulse transcranial magnetic stimulation (TMS) with a MagPro X100 stimulator. Change in SICI will be calculated as the difference between post-intervention and pre-intervention measurements. Negative values indicate increased intracortical inhibition.
Change in Root Mean Square of Successive Differences (RMSSD)
Time frame: Baseline (Day 0), pre/post each intervention session (Days 1-13), and post-trial (Day 14)
The root mean square of successive differences (RMSSD), will be assessed using a three-lead electrocardiogram (ECG) and reported in milliseconds (ms). Higher RMSSD values indicate greater parasympathetic (vagal) activity and heart rate variability.
Who can participate
This study lists these criteria on ClinicalTrials.gov. A study coordinator reviews eligibility during screening — this page does not determine whether you qualify.
Inclusion criteria
- Established HIV infection
- Glove/stocking dysesthesias lasting for ≥3 months
- HIV-associated peripheral neuropathy (HIV-PN) related symptoms ≥4 (on a scale of 0-10) within the last week
- Stable medical care (i.e., no changes in Antiretroviral Therapy or pain medication within 2 months of enrollment)
- Able to read the consent form, demonstrate understanding of study procedures and requirements, and independently provide written informed consent
Exclusion criteria
- Unstable cardiac disease
- Implanted electronic or magnetic devices (e.g., pacemaker, cochlear implants, medication pumps, and other implanted neurostimulation systems)
- Head or neck cancer or metastases
- Recent ear trauma or metal implants in the head
- History of epilepsy, unprovoked seizure, stroke, brain tumor, significant traumatic brain injury, prior intracranial surgery, or other neurological condition associated with increased seizure risk
- Active or uncontrolled comorbidities that independently cause neuropathy (e.g., recent chemotherapy, uncontrolled diabetes with documented neuropathic complications)
- Clinical evidence of non-HIV neuropathy (e.g., neuropathic symptoms predating HIV diagnosis, uncontrolled diabetes)
- Known allergy to tape/adhesive
- Ferromagnetic or non-MRI-compatible metal in the head, neck, eye, or cranial region, including aneurysm clips, retained metal fragments, bullets, shrapnel, or other metallic implants not demonstrated to be TMS-compatible.
- Pregnancy or actively breast feeding
Where
- Miami, Florida
Collaborators
National Institute of Neurological Disorders and Stroke (NINDS)
Related conditions & keywords
Frequently asked questions
What is a clinical trial?
A clinical trial is a research study that tests new medical treatments, drugs, devices, or procedures to determine their safety and effectiveness. Trials are carefully designed and monitored to protect participants while advancing medical knowledge.
Is it safe to participate?
Clinical trials follow strict safety guidelines and ethical standards. Trials must be reviewed and approved, and participants are closely monitored by medical professionals throughout the study. You can withdraw at any time if you choose.
Will I be compensated?
Many clinical trials offer compensation for your time, travel expenses, and inconvenience. The specific compensation varies by study and will be discussed during the screening process. All study-related medical care is typically provided at no cost to participants.
Will I receive a placebo instead of treatment?
When effective treatment exists, participants typically receive either the standard treatment plus the study intervention, or the standard treatment plus placebo. You would not be denied effective care. Placebos are primarily used when no proven treatment is available, or in addition to standard care. Your trial consent form will clearly explain what treatments you may receive.
Can I leave a trial if I change my mind?
Absolutely. Participation in clinical trials is completely voluntary. You have the right to withdraw from the study at any time, for any reason, without penalty or loss of benefits to which you are otherwise entitled.
How long does a clinical trial last?
Trial duration varies widely depending on the study design and purpose. Some trials last just a few weeks, while others may continue for months or years. The study coordinator will provide specific timeline information during your screening call.
Data: ClinicalTrials.gov · synced Oct 6, 2026 · Source of record for eligibility and locations