Last reviewed · How we verify
NCT06817499
Treatment of Olfactory Dysfunction Using Vagus Nerve Stimulation
NA trial testing Nasal Insert + VNS in Hyposmia in 40 participants. Participants enrolled and being followed up; not accepting new ones.
15 May 2026
Quick facts
| Lead sponsor | Karolinska Institutet |
|---|---|
| Phase | NA |
| Status | Active, enrolled |
| Study type | INTERVENTIONAL |
| Allocation | randomized |
| Design | parallel |
| Masking | none |
| Primary purpose | treatment |
| Enrollment | 40 |
| Start date | 15 March 2025 |
| Primary completion | 15 May 2026 |
| Estimated completion | 15 October 2026 |
| Sites | 1 location across Sweden |
Drugs / interventions tested
- Nasal Insert + VNS
- Nasal Insert
Conditions studied
- Hyposmia — all drugs for Hyposmia →
Sponsor
Karolinska Institutet
Who can join
Adults 18 to 65, any sex, with Hyposmia. Patients with the condition only — healthy volunteers not accepted.
Sponsor's own description
Hyposmia, a reduced sense of smell, is commonly linked to viral infections like COVID-19. Currently, the sole recommended treatment is olfactory training, a method that is both time-intensive and limited in its effectiveness. Our team has previously evaluated a new type of olfactory training using nasal inserts that show increased adherence to training (compared to standard olfactory training using common household odors) but with similar treatment effect. The investigators recently demonstrated that brief transcutaneous vagus nerve stimulation (VNS) in the cymba conchae region affected participants olfactory abilities but only when a stimulation frequency relevant to olfactory bulb processing frequencies was used. The notion that VNS might modulate olfactory functions stems from findings in rats where VNS of the cervical nerve inhibited neurons within the periglomerular layers of the olfactory bulb. Although there is no known monosynaptic connection between the vagus nerve and the olfactory system in humans, VNS activates areas with mono-synaptic connections to the olfactory bulb, such as amygdala, hippocampus, and the hypothalamus. Given that VNS modulates the olfactory bulb in rats and our treatment protocol modulate olfactory functions in humans, the investigators hypothesize that VNS, when paired with olfactory training, will enhance olfactory functions in patients with hyposmia.
Publications & conference data
No peer-reviewed publications indexed yet for this trial.
Verify or expand the search:
- PubMed search for NCT06817499
- Europe PMC full search
- ASCO Meeting Library
- ESMO Meeting Library
- bioRxiv preprints
- medRxiv preprints
- Google Scholar
Related trials
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Verify against primary sources
- ClinicalTrials.gov — authoritative US registry record
- WHO ICTRP — international registry index
- EU Clinical Trials Register
- Sponsor press releases (Google)
- Trial protocol + status: ClinicalTrials.gov NCT06817499 (US National Library of Medicine, public domain)
- Drug + disease cross-links: matched in real time against Drug Landscape's normalised drug + company + condition tables
- Sponsor: as reported to ClinicalTrials.gov by Karolinska Institutet
- Last refreshed: 27 August 2025
Drug Landscape aggregates and links these public records for informational use only. Always verify against the primary source before clinical or regulatory decisions. Canonical URL: https://druglandscape.com/trial/NCT06817499.
Primary sources · FDA · ClinicalTrials.gov · EMA · SEC EDGAR · ChEMBL · Wikidata · full sourcing