Vagus nerve stimulation

Also known as VNS, Vagal nerve stimulation, Vagus nerve stimulator

Vagus nerve stimulation sends small electrical pulses to the vagus nerve, a long nerve linking the brain with the heart, lungs and gut. Implanted systems are FDA-approved for epilepsy and for arm rehabilitation after stroke, but the evidence for depression and for rheumatoid arthritis is much less settled.

CommercialDemonstratedReviewed 21 Oct 2026
AI illustration · Illustrative scene, not a photograph of the specific device or experiment.

In plain language

The vagus nerve carries signals in both directions between the brain and many organs in the chest and abdomen. Stimulation is delivered by a small device that sends mild pulses along the nerve. The aim is to change how the brain or the body's own control systems behave, rather than to stimulate muscles directly.

The treatment is best established for epilepsy, where an implanted device has been approved in the United States since 1997 (PMA P970003). In 2021 trade press reported FDA approval of a version for people with arm weakness after stroke, to be used alongside rehabilitation exercises. Trials of the same approach in rheumatoid arthritis have produced modest results so far. This profile does not review the evidence for other conditions.

Technical explanation

Implanted systems deliver electrical pulses to the vagus nerve, with the stimulus pattern set by the clinician. Because the vagus nerve contains both sensory and motor fibres, the effects are complex and not fully understood, and the mechanism that links stimulation to seizure reduction, motor recovery or inflammation is still a research question.

The approval history is specific to each indication. The FDA record for the VNS Therapy System (PMA P970003) gives a decision date of 16 July 1997 and the generic device name 'stimulator, autonomic nerve, implanted for epilepsy'. Trade press reported in August 2021 that the FDA had approved the Vivistim Paired VNS System for chronic ischaemic stroke rehabilitation, following the 108-patient VNS-REHAB pivotal trial. Each approval covers only its stated indication and patient group.

In rheumatoid arthritis, the RESET-RA pivotal trial used an implanted device on the vagus nerve with a sham-controlled design. Its primary endpoint was an ACR20 response at 3 months, which was 35.2% with active stimulation against 24.2% with sham. Open-label follow-up reported response rates of 50% at 6 months and 52.8% at 12 months, but without a control group these numbers cannot show that the effect was caused by stimulation. The evidence for wider claims, such as effects on inflammation in other diseases or on mood, is not established by the sources reviewed here.

What the evidence says

Each statement is typed by the strength of its evidence and linked to the source that supports it.

Demonstrated Shown in a published experiment, test or shipping product.

The FDA PMA record shows approval of the VNS Therapy System (PMA P970003) with a decision date of 16 July 1997. The record's generic device name is 'stimulator, autonomic nerve, implanted for epilepsy'.

Sources: [1] · PMA record P970003: decision date, applicant and generic device name. Indication wording not checked against the Summary of Safety and Effectiveness. · medium confidence

Reported, unverified Stated by a company or team but not independently confirmed.

Trade press reported on 27 August 2021 that the FDA had approved the MicroTransponder Vivistim Paired VNS System through premarket approval, described as the first vagal nerve stimulation system for chronic ischaemic stroke rehabilitation, to be used alongside rehabilitation.

Sources: [3] · RAPS article text: pathway and indication wording. FDA record and exact approval date not checked. · medium confidence

The VNS-REHAB pivotal trial randomised 108 chronic ischaemic stroke patients 1:1 to upper-limb rehabilitation paired with active vagus nerve stimulation or with sham stimulation. The primary result is not stated here because the full paper was not read.

Sources: [2], [3] · Lancet title and Crossref record; RAPS trial size and 1:1 randomisation to treatment or sham · medium confidence

RESET-RA was a double-blind, sham-controlled pivotal trial of 242 patients with inadequate response to, or intolerance of, a biologic or targeted synthetic DMARD, published online in Nature Medicine on 22 December 2025.

Sources: [4], [5] · Crossref record (title, online date); Healio design, eligibility and enrolment. Full paper not opened. · medium confidence

At 3 months, the primary endpoint ACR20 response was 35.2% with active stimulation and 24.2% with sham stimulation in RESET-RA (P = .0209), a difference of about 11 percentage points.

Sources: [5], [4] · Healio report of primary endpoint; numbers not checked against the full paper · medium confidence

In open-label follow-up with no control group, ACR20 responses in RESET-RA were 50% at 6 months and 52.8% at 12 months, figures reported by the sponsor and by secondary coverage.

Sources: [5], [6] · Healio results section; SetPoint press release · medium confidence

SetPoint Medical describes the SetPoint System as FDA-approved and indicated for adult patients with moderately to severely active rheumatoid arthritis; the approval date and FDA documents were not verified for this profile.

Sources: [6] · Press release: indication wording and approval statement · low confidence

The first-listed RESET-RA author, John R. P. Tesser, reports consulting fees from SetPoint Medical, the device maker that sponsored the trial.

Sources: [5] · Healio: author disclosures. Sponsorship from Crossref funder field.

Limitations and open problems

  • The approvals are indication-specific. The 2021 stroke approval does not show that stimulation works for other conditions, and the rheumatoid arthritis evidence here rests on one pivotal trial.
  • The pivotal stroke trial, VNS-REHAB, enrolled 108 patients. The sources reviewed here do not report its long-term recovery outcomes.
  • In RESET-RA the difference at 3 months was about 11 percentage points, and about two thirds of patients on active stimulation did not reach an ACR20 response at that point.
  • The rheumatoid arthritis figures at 6 and 12 months come from open-label follow-up with no control group. The device maker sponsored the trial, and the first-listed author reports consulting fees from that company.
  • Implantation needs surgery. Healio reports serious adverse events in 1.6% of RESET-RA participants, all perioperative and resolved.
  • Wider claims, such as effects on inflammation in other diseases, mood beyond approved indications or general wellbeing, are not established by the sources reviewed here.

Possible future uses

Speculative

Ideas, not predictions. None of these has been demonstrated.

  • Testing vagus nerve stimulation in other inflammatory diseases, which would need controlled trials before any clinical use.
  • Closed-loop systems that switch stimulation on when a sensor detects a change in symptoms, such as a seizure warning or a stroke-recovery window.
  • Wider use in treatment-resistant depression if larger controlled trials confirm a benefit.

Timeline

  1. 16 Jul 1997FDA decision on the VNS Therapy System (PMA P970003). The PMA record gives the generic device name 'stimulator, autonomic nerve, implanted for epilepsy'. Sources: [1]
  2. Apr 2021The Lancet publishes VNS-REHAB, a 108-patient pivotal trial of vagus nerve stimulation paired with upper-limb rehabilitation after ischaemic stroke. Sources: [2]
  3. Aug 2021Trade press reports FDA premarket approval of the Vivistim Paired VNS System for chronic ischaemic stroke rehabilitation (RAPS article dated 27 August 2021). Sources: [3]
  4. 22 Dec 2025Nature Medicine publishes RESET-RA online, a 242-patient sham-controlled trial of an implanted vagus nerve device in rheumatoid arthritis. Sources: [4], [5]

Futures this could help bring about

AI illustration
How far away?

Treating illness through the vagus nerve

Pilots · 6 of 8 steps done

Related breakthroughs

Glossary

Vagus nerve
A long cranial nerve that carries signals between the brain and organs in the neck, chest and abdomen, including the heart, lungs and gut.
Sham stimulation
A control in which the device looks and feels the same but delivers no active stimulation, used to separate real effects from expectation.
ACR20
A standard rheumatoid arthritis response measure, met when a patient improves by at least 20% on the American College of Rheumatology criteria.
Premarket approval (PMA)
The FDA pathway for high-risk implantable devices, which requires scientific evidence of safety and effectiveness for a specific use.

Sources

  1. government report
    VNS Therapy System, PMA P970003
    US Food and Drug Administration, 16 Jul 1997. Accessed 21 Oct 2026.
  2. peer reviewed paper
    Vagus nerve stimulation paired with rehabilitation for upper limb motor function after ischaemic stroke (VNS-REHAB): a randomised, blinded, pivotal, device trial
    Dawson, Liu, Francisco et al.. The Lancet, Apr 2021. DOI: 10.1016/S0140-6736(21)00475-X. Accessed 21 Oct 2026.
  3. news
    Vagal nerve stimulator for stroke rehab nabs FDA nod
    Kari Oakes. RAPS (Regulatory Focus), 27 Aug 2021. Accessed 21 Oct 2026.
  4. peer reviewed paper
    Vagus nerve-mediated neuroimmune modulation for rheumatoid arthritis: a pivotal randomized controlled trial
    Tesser JRP, Crowley AR, Box EJ et al.. Nature Medicine, 22 Dec 2025. DOI: 10.1038/s41591-025-04114-7. Accessed 21 Oct 2026.
  5. news
    Vagus nerve stimulator shows ongoing efficacy in rheumatoid arthritis
    Rob Volansky. Healio, 4 Feb 2026. Accessed 21 Oct 2026.
  6. company announcement
    Landmark RESET-RA study published in Nature Medicine demonstrates durable efficacy and safety of the SetPoint System for rheumatoid arthritis
    SetPoint Medical (via BioSpace), 5 Jan 2026. Accessed 21 Oct 2026.

Revision history

3 changes since this profile was created.

Changes on 21 Oct 2026
Published on owner instruction (content loop iteration 18)78bdfe0
Sources and claims re-checked against originalsfbb434c
Initial profile drafted from primary sources7e66249