ClinicalTrials.gg
RecruitingNCT07804199taVNSUpdated Oct 5, 2026

taVNS in Veterans With Knee OA (AVAHCS)

An interventional study of Methylprednisolone acetate and taVNS in Knee Osteoarthritis, sponsored by VA Office of Research and Development. Recruiting at 1 site in United States. Open to participants aged 45 Years to 75 Years. Per ClinicalTrials.gov, last updated 2026-10-05.

Sponsored by VA Office of Research and Development · Not applicable, Interventional, and Treatment

From the registry’s dates

  • Started Sep 2026; still recruiting 1 month later.
Updated Oct 5, 2026Now RecruitingSite recruiting status changed+2 moreGo to Updates ↓
Phase
Not applicable
Study type
Interventional
Enrollment
40
Allocation
Randomized
Ages
45 Years to 75 Years
Sex
All
01

Where this study stands

Counted across the records on this site · 2026-11-12

Among 17 studies in Osteoarthritis, Knee by VA Office of Research and Development — 7 open to participants now, 8 under way, 2 of them phase 3. Osteoarthritis, Knee · VA Office of Research and Development.

Planned enrollment
10th of 16
40 · median 85
Started
2026
with 3 others
No phase
10 of 17
3 open now
Registered
17th of 17
by date

Among the 17 studies in Osteoarthritis, Knee by VA Office of Research and Development, this one is the 10th largest by planned enrollment of the 16 interventional ones that give a count, is one of 4 that started in 2026, is one of 10 with no phase, and was the 17th registered.

Osteoarthritis, Knee

3,292 studies on the registry are indexed under Osteoarthritis, Knee; 623 are open to participants now.

Browse Osteoarthritis, Knee studies →

Open to participants now

7 of the 17 studies in Osteoarthritis, Knee by VA Office of Research and Development are open now, in 1 country. Recruiting first, the newest first:

1 more — sign in →

By country, each count listing its studies:

All 7 open studies →

Where they have run

Who these studies take

Of the 382 Osteoarthritis, Knee studies recruiting now, 176 (46%) set no upper age limit and 113 (30%) stop at 75 or younger; 19 take children under 18; 39 take healthy volunteers.

This study: 45 Years to 75 Years · all sexes · no healthy volunteers.

The full table on the hub →

This tab as a report to print or save as PDF → With an account.

Was this useful?
Watch this landscapeDownload CSVNarrow it in search →With an account: a weekly mail of what changed among 17 studies in Osteoarthritis, Knee by VA Office of Research and Development, or all of them as a file.
02

Study summary

The objectives of this study are to identify an optimal transcutaneous auricular vagus nerve stimulation (taVNS) dosing regimen for pain relief and anti-inflammatory effects in Veterans with knee osteoarthritis (OA), compared to corticosteroid injection (CSI), and lay the groundwork for future combinatorial therapies with cell-based approaches. The population for this study is Veterans with osteoarthritis (OA). This single-center, randomized pilot study will enroll participants with knee OA, who will be allocated to CSI (n=10), high-dose taVNS (n=15; 1-2 hours/day, 7 days/week), or low-dose taVNS (n=15; 30-60 min/day, 3 days/week) for 12 weeks. Synovial fluid and blood samples will be collected at baseline, 4, and 12 weeks for biomarker analysis (pro-inflammatory cytokines: TNF-, IL-6, IL-1 ; anti-inflammatory mediators: IL-10, TGF-). The approximate study duration for each individual participant is 12 weeks of treatment with assessment visits at baseline, one month, and three months. Participants will be recruited at the Atlanta VA. The anticipated total enrollment is 40 participants. No specimens or data will be banked for future research use. Informed consent will be obtained from participants in person via signatures on written informed consent forms.

Read the detailed description

This pilot study will be the first to test home-based taVNS against corticosteroid injections (CSI) in knee osteoarthritis (KOA) to assess their effects on pain, function, and serum/synovial fluid pro and anti-inflammatory biomarkers. Adult participants diagnosed clinically and/or radiographically with KOA (n=40) will be randomized to CSI (n=10) or 12 weeks of taVNS (high dose n=15; low dose n=15) and assessed pre-procedure and at 1- and 3-month timepoints. The following outcome measures will be assessed: PEG-3, DVPRS, NIH-PROMIS, KOOS, and Central Sensitization Inventory. In addition, biomarker levels in the serum and synovial fluid will be measured at baseline, 1- and 3-month timepoints.

This study will be the first to 1) directly compare taVNS against gold-standard CSI, 2) examine taVNS effects on cytokines in knee OA as compared to CSI, 3) target an ideal taVNS dosing strategy for knee OA, and 4) utilize Parasym , a home-based taVNS device previously shown to reduce heart failure symptoms and decrease TNF- 17 that has been classified as non-significant risk (NSR) by the FDA. The investigators are therefore testing a novel Veteran-centric, nonpharmacological intervention for knee OA; taVNS with Parasym offers a safe, self-administered alternative to opioids and invasive procedures, with minimal side effects and high potential for real-world implementation in the Veteran population.

Aim 1: Identify an ideal taVNS dosing regimen for analgesic effects. (30-60 minutes per day, 3 days per week 4,17 versus 1-2 hours per day, 7 days per week17 for 12 weeks) on clinical improvements in pain and function. Hypothesis for Aim 1: Pain (primary outcome), measured by the PEG-3 (3-item scale assessing pain intensity, interference with activity, and enjoyment of life)18 and DVPRS (assesses pain intensity + interference with activity, sleep, mood, stress)19 and function (secondary outcome) measured by the KOOS (Knee Injury and Osteoarthritis Outcome Score)20 and NIH PROMIS measures21 will be more improved in those undergoing high-dose taVNS (n=15) than vs. low-dose taVNS (n=15) or CSI (n=10). Central sensitization inventory will also be collected to evaluate it as a co-variate in predicting and monitoring treatment response.

Aim 2: Evaluate taVNS dose-dependent modulation of biomarkers associated with inflammation in Aim 1 participants. Synovial fluid and peripheral blood will be obtained pre-procedure and at 4- and 12-weeks following initiation of therapy. Hypothesis for Aim 2: taVNS results in greater reductions in pro-inflammatory cytokines (e.g., TNF- , IL-6, IL-1 ) and increased levels of anti-inflammatory mediators (e.g., IL-10, TGF- ) in synovial fluid and peripheral blood compared to CSI. The investigators expect that the higher dose group will demonstrate more pronounced changes in anti-inflammatory biomarkers as compared to low dose taVNS or CSI.

This study addresses a critical need for innovative, non-opioid OA therapies and supports the CReATE Motion Center's mission to advance regenerative therapies for Veterans. Based on results of this study, the investigators will choose the taVNS dosing strategy that best enhances clinical and anti-inflammatory effects. This pilot study has the potential to advance a novel, non-pharmacological approach to pain relief and functional recovery in a population with high unmet needs and is a critical first step to our understanding of dose optimization in taVNS for knee OA-related pain, function, and anti-inflammatory effects.

Our project is designed as a foundational step toward future combinatorial trials pairing taVNS with other therapies for chondroprotection.

03

Conditions studied

  • Knee Osteoarthritis

Keywords

  • Pain
  • Knee osteoarthritis
  • Biomarker analysis
  • Veterans
  • Transcutaneous auricular vagus nerve stimulation
  • Vagus nerve
04

Who can participate

The criteria were revised on the registry on Oct 5, 2026. See what changed

Ages eligible
45 Years to 75 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Clinical diagnosis of knee osteoarthritis according to the American College of Rheumatology (ACR) criteria, confirmed by radiologic evidence of the same.
  • Moderate to severe knee pain, as assessed by the Defense Veterans Pain Rating Scale (DVPRS), a validated pain scale (score ≥4)
  • Willingness to discontinue current knee osteoarthritis (OA) pain medications (except permitted rescue medication such as acetaminophen/paracetamol) during the trial
  • Ability to provide and comply with all study procedures
  • Ambulatory and able to attend all study visits

Exclusion criteria

Exclusion Criteria:

  • History or evidence of inflammatory joint disease (e.g., rheumatoid arthritis, spondyloarthropathy), secondary or metabolic causes of arthritis, or significant trauma to the knee within 3 months prior to screening
  • Recent or planned major knee surgery on the index knee (arthroplasty or arthroscopy within 6 months)
  • Received intra-articular or hyaluronic acid injections in the index knee within 12 weeks prior to screening, or systemic corticosteroids within 30 days
  • to transcutaneous auricular vagus nerve stimulation (taVNS), such as:

    • Metal implants above the neck
    • Active ear infection, recent ear trauma, or chronic ear/facial pain
    • Prior vagus nerve surgery (including vagotomy) or ongoing vagus nerve stimulation (VNS) therapy for another condition
  • Severe comorbidities (e.g., uncontrolled liver/kidney disease, active , uncontrolled hypertension or cardiovascular disease, uncontrolled diabetes with neuropathy)
  • Participation in another interventional clinical trial within the past 2 months
  • Inability to provide or comply with protocol requirements (e.g., significant cognitive impairment)
  • Any unstable or severe psychiatric disorder that, in the investigator's opinion, would compromise safety or compliance
Terms in these criteria, in plain language(4)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Corticosteroids (steroids)

Anti-inflammatory medicines such as prednisone, prednisolone and dexamethasone — not the anabolic steroids used for muscle.

Studies differ in what they allow: check which steroid medicines, routes (tablets, injections, creams, inhalers, eye drops) and doses this study accepts.

Contraindication

A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.

Cancer (malignancy)

Malignancy means cancer. Criteria about another or earlier malignancy ask whether you have had a different cancer, usually within a set number of years.

Some are commonly allowed, such as treated skin cancers other than melanoma and early cancers removed completely — check the exceptions this study lists.

05

Study design

Phase
Not applicable
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
40 participants (estimated)

Study arms

  • Other
    Standard-of-care CSI

    Participants allotted to this group will receive gold-standard corticosteroid injection (CSI), a standard-of-care option for treating and managing knee osteoarthritis (KOA) pain.

    Drug: Methylprednisolone acetate

  • Active comparator
    Low-dose taVNS

    Transcutaneous auricular vagus nerve stimulation (taVNS) is a self-administered, home-based, non-invasive therapy with minimal risk of side effects. Mechanistically, taVNS targets auricular vagal afferents and requires afferent signaling to the nucleus tractus solitarius (NTS) to activate downstream efferent pathways in the central nervous system, including higher brain regions involved in pain processing (Fig 1), exerting anti-nociceptive effects. Participants allocated to this group will receive low-dose taVNS (n=15; 30-60 min/day, 3 days/week) for 12 weeks.

    Device: taVNS

  • Active comparator
    High-dose taVNS

    Transcutaneous auricular vagus nerve stimulation (taVNS) is a self-administered, home-based, non-invasive therapy with minimal risk of side effects. Mechanistically, taVNS targets auricular vagal afferents and requires afferent signaling to the nucleus tractus solitarius (NTS) to activate downstream efferent pathways in the central nervous system, including higher brain regions involved in pain processing (Fig 1), exerting anti-nociceptive effects. Participants allocated to this group will receive high-dose taVNS (n=15; 1-2 hours/day, 7 days/week) for 12 weeks.

    Device: taVNS

Interventions

  • FDA-approved injection treatment applied to the knee for purposes of KOA pain management.

    Also known as: Depo-Medrol, Depo-Medrate, Depo-Medrone, gold-standard corticosteroid injection (CSI)

  • DevicetaVNS

    Transcutaneous auricular vagus nerve stimulation (taVNS) is a self-administered, home-based, non-invasive therapy with minimal risk of side effects. Mechanistically, taVNS targets auricular vagal afferents and requires afferent signaling to the nucleus tractus solitarius (NTS) to activate downstream efferent pathways in the central nervous system, including higher brain regions involved in pain processing (Fig 1), exerting anti-nociceptive effects.

    Also known as: Nurosym

06

What researchers measure

Primary outcomes

  1. Improvements in Clinical Pain (DVPRS)

    The DVPRS is a pain measurement tool used in the U.S. Military Health System and VA to assess pain intensity and impact on quality of life. It utilizes a numerical rating scale enhanced by words that describe function, sleep, activity, mood, and color-coding to enhance communication. Clinical pain, as measured by the Defense Veterans Pain Rating Scale (DVPRS), will be our primary outcome. This measure is rated on a scale of 0 to 10, with 0 being "no pain" and 10 being "as bad as it could be, nothing else matters". Assessments will be administered at the initial visit (week 1), 4-week follow-up visit, 12-week follow-up visit, and 6-month follow-up visit.

    Time frame: Through study completion, average of 9 months

  2. Concentration of Pro-inflammatory Cytokines (Blood)

    Biomarker analysis (pro-inflammatory cytokines: TNF-α, IL-6, IL-1β) of blood samples, collected at baseline,1-month post-treatment, and 3 months post treatment. The hypothesis is that there will be an increase in anti-inflammatory mediators and decrease in pro-inflammatory cytokines with high-dose taVNS in comparison with the other groups, and that this will correlate with improved clinical outcomes. Specimens will be taken at the initial visit (week 1), 4-week follow-up visit, and 12-week follow-up visit.

    Time frame: Through study completion, average of 9 months

  3. Concentration of Pro-inflammatory Cytokines (Synovial Fluid)

    Biomarker analysis (pro-inflammatory cytokines: TNF-α, IL-6, IL-1β; anti-inflammatory mediators: IL-10, TGF-β) of synovial fluid, collected at baseline,1-month post-treatment, and 3 months post treatment. The hypothesis is that there will be an increase in anti-inflammatory mediators and decrease in pro-inflammatory cytokines with high-dose taVNS in comparison with the other groups, and that this will correlate with improved clinical outcomes. Specimens will be taken at the initial visit (week 1), 4-week follow-up visit, and 12-week follow-up visit.

    Time frame: Through study completion, average of 9 months

  4. Concentration of Anti-inflammatory Mediators (Blood)

    Biomarker analysis (anti-inflammatory mediators: IL-10, TGF-β) of blood samples, collected at baseline,1-month post-treatment, and 3 months post treatment. The hypothesis is that there will be an increase in anti-inflammatory mediators and decrease in pro-inflammatory cytokines with high-dose taVNS in comparison with the other groups, and that this will correlate with improved clinical outcomes. Specimens will be taken at the initial visit (week 1), 4-week follow-up visit, and 12-week follow-up visit.

    Time frame: Through study completion, average of 9 months

  5. Concentration of Anti-inflammatory Mediators (Synovial Fluid)

    Biomarker analysis (anti-inflammatory mediators: IL-10, TGF-β) of synovial fluid and blood samples, collected at baseline,1-month post-treatment, and 3 months post treatment. The hypothesis is that there will be an increase in anti-inflammatory mediators and decrease in pro-inflammatory cytokines with high-dose taVNS in comparison with the other groups, and that this will correlate with improved clinical outcomes. Specimens will be taken at the initial visit (week 1), 4-week follow-up visit, and 12-week follow-up visit.

    Time frame: Through study completion, average of 9 months

Secondary outcomes

  1. Changes in Pain Frequency and Intensity (PEG-3)

    The PEG is a 3-item patient-reported measure derived from the Brief Pain Inventory . It assesses average pain intensity, interference with enjoyment of life, and interference with general activity over the past week. Its minimally clinically important difference is 1-2 points. Assessments will be administered at the initial visit (week 1), 4-week follow-up visit, and 12-week follow-up visit.

    Time frame: Through study completion, average of 9 months

  2. Changes in Knee Pain, Function, and QOL (KOOS-12)

    The KOOS-12 is a 12-item scale that assesses knee pain, function, and quality of life (QOL). Items are rated on a 5-point scale (0=no problems, 4=extreme problems), summed, and converted to a 0-100 scale (0=severe problems, 100=no problems). The KOOS-12 evaluates pain frequency and intensity during common activities (i.e. walking on a flat surface, going up or down stairs, getting in and out of the car), offering a comprehensive view of limitations in activities of daily living (ADLs) attributable to knee pain. The MCID ranges from 14.2 to 21.9 points. Assessments will be administered at the initial visit (week 1), 4-week follow-up visit, and 12-week follow-up visit.

    Time frame: Through study completion, average of 9 months

  3. Patient Reported Improvements (NIH-PROMIS)

    NIH-PROMIS is a validated, 29-item patient-reported outcome measure assessing health-related quality of life (QOL) across seven domains: anxiety, depression, fatigue, pain interference, physical function, disturbance, and social participation, plus a single pain intensity item. Each domain has four items scored independently, mostly reflecting symptoms over the past seven days (except physical function which is not time bound). This instrument supports the generation of global physical and mental health summary scores, providing an overview of participants' quality of life. Scores are standardized as T-scores (mean 50; standard deviation 10) for ease of interpretation. Minimally important differences ranges from 2 to 6 points across domains, with values of 3 to 5 points commonly cited for pain interference and physical function in musculoskeletal conditions. Assessments will be administered at the initial visit (week 1), 4-week follow-up visit, and 12-week follow-up visit.

    Time frame: Through study completion, average of 9 months

  4. Treatment Prediction and Monitoring (Central Sensitization Inventory)

    Central sensitization inventory will also be collected to evaluate it as a co-variate in predicting and monitoring treatment response. Assessments will be administered at the initial visit (week 1), 4-week follow-up visit, and 12-week follow-up visit.

    Time frame: Through study completion, average of 9 months

07

Study locations

1 of 1 sites recruiting
  • Atlanta VA Medical and Rehab Center, Decatur, GA
    Decatur, Georgia 30033-4004, United States
    Recruiting
    • Anna Woodbury, MD · ContactAnna.Woodbury@va.gov · (404) 321-6111
    • Anna Woodbury, MD · Principal investigator
    • Mercy A Udoji, MD · Principal investigator
08

References and documents

Individual participant data

Plan to share: No

09

Timeline

1 registry update since Sep 25, 2026
ElapsedEstimatedEstimated, not yet reachedDate before it movedWhere the date was before it movedSimilar studies: half by the dot; the band is the middle halfHalf of similar studies reached it by the dot; the band is the middle half, from a quarter to three quarters

Started Sep 2026 (actual). Primary completion is estimated for Jan 2028, 15 months after the start.

Of 1,111 non-industry interventional studies with no phase under Osteoarthritis, Knee, half reached primary completion within 18 months of starting (the median), counting those still running; a quarter within 8 and three quarters within 36. This study's planned 15 months is below that.

Counting every sponsor, half of 1,251 studies reached it within 18 months; a quarter within 8 and three quarters within 36.

Start moved once since we started tracking on Sep 25, 2026: Oct 2026 → Sep 2026, on Oct 5, 2026.

Earlier changes are on the record history on ClinicalTrials.gov ↗

How these figures are worked out, and which studies are left out of them.

Registered
Aug 21, 2026
First posted
Sep 4, 2026
StartActual
Sep 29, 2026was Oct 2026
Primary completionEst.
Jan 1, 2028
CompletionEst.
Jan 1, 2028
Last update
Oct 5, 2026
What these dates mean
Start.
When the first participant enrolled; while estimated, when the study expects to open to recruitment.
Primary completion.
When the last participant was examined or treated to collect data for the study's main question, its primary outcome. A study that stopped early gives the date its data collection stopped.
Completion.
When the last participant's last visit took place, for every outcome, secondary ones and side effects included: the end of the study. Often later than primary completion, sometimes the same day.
Actual and Est.
Actual means the registry says the date has happened. Est. (estimated) is a date the sponsor plans or expects. It can still move, and the sponsor is expected to change it to actual once it has passed.
Status
Not yet recruiting→Recruiting
changed Oct 5, 2026
Sites
Atlanta VA Medical and Rehab Center, Decatur, GA is now Recruiting
Oct 5, 2026
Start date
Oct 1, 2026→Sep 29, 2026 (actual)
Oct 5, 2026
Eligibility
1 exclusion criterion edited, 2 added
What changed in the criteria
Exclusion criteria
  • AddedMetal implants above the neck
  • EditedoMetal implants above the neck oActiveActive ear infection, recent ear trauma, or chronic ear/facial pain oPrior vagus nerve surgery (including vagotomy) or ongoing VNS therapy for another condition
  • AddedPrior vagus nerve surgery (including vagotomy) or ongoing vagus nerve stimulation (VNS) therapy for another condition
Oct 5, 2026
Show all 1 update
  1. Oct 5, 2026
    Not yet recruiting→Recruiting
    Atlanta VA Medical and Rehab Center, Decatur, GA is now Recruiting
    Start date Oct 1, 2026→Sep 29, 2026 (now actual)
    Eligibility 1 exclusion criterion edited, 2 added
    What changed in the criteria
    Exclusion criteria
    • AddedMetal implants above the neck
    • EditedoMetal implants above the neck oActiveActive ear infection, recent ear trauma, or chronic ear/facial pain oPrior vagus nerve surgery (including vagotomy) or ongoing VNS therapy for another condition
    • AddedPrior vagus nerve surgery (including vagotomy) or ongoing vagus nerve stimulation (VNS) therapy for another condition
    + 2 other changes: description and design details

From the registry record's own update history. This site started tracking changes on Sep 25, 2026; for anything earlier, see the record history on ClinicalTrials.gov ↗

10

Registry details

Key details

Study ID
NCT07804199
Responsible party
Sponsor
First posted
Sep 4, 2026
Start date
Sep 29, 2026
Primary completion
Jan 1, 2028 (estimated)
Completion
Jan 1, 2028 (estimated)
Last update
Oct 5, 2026

Study contacts

Anna Woodbury, MD
Contact
Anna.Woodbury@va.gov
(404) 321-6111 ext. 6939
Anna M Ree, BA
Contact
anna.ree@va.gov
(404) 321-6111 ext. 202561
Anna Woodbury, MD
principal investigator · Atlanta VA Medical and Rehab Center, Decatur, GA
Mercy A Udoji, MD
principal investigator · Atlanta VA Medical and Rehab Center, Decatur, GA

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
Yes
View the source record on ClinicalTrials.gov ↗

Interested in this study?

Eligibility is decided by the study team. Share this record with your doctor or contact the team directly.

Contact study team

Follow this study

Get an email when the registry record changes — status, dates, results — or when someone posts here.

Sign in to follow

Discussion

Questions and observations about this study, from anyone following it. Not medical advice, and not a channel to the study team — their contact details are on the registry record.

Sign in to join the discussion. Reading takes no account; posting does. You choose a display name, and a pseudonym is the default.

Nothing here yet. If you are running this trial, taking part in it, or weighing whether to, this is the place to say so.

Start the discussion