Recruiting
Phase 2

TNS & ST

Sponsor:

Medical University of South Carolina

Code:

NCT07689773

Conditions

Olfactory Impairment

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Not accepted

Interventions

Trigeminal Nerve Stimulation-enhanced Smell Training

Study Details

Brief summary:

Smell dysfunction significantly impacts quality of life and safety, with limited effective treatments. This open-label study evaluates the preliminary efficacy of combining non-invasive trigeminal nerve stimulation (TNS) with standard smell training (ST) to improve olfactory function. Participants will complete 8 weeks of at-home treatment and attend three in-person visits for assessment. Improvements in smell, mood, sleep, and quality of life will be measured.

Conditions

Olfactory Impairment

Study ID

NCT07689773

Start date

Jul 10, 2026

Status verified date

Aug, 2026

Completion date

Jun 30, 2028

Anticipated

Primary completion date

Jun 30, 2028

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18 - 70+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • Age 18-80
  • Self-reported or medically documented smell loss
  • Treatment-seeking for their smell loss
  • Naïve to TNS
  • Able to comprehend English and provide informed consent

Exclusion Criteria:

  • Medical Records not available to confirm eligibility
  • Documented/Suspected head injury (e.g. sport, accident, blast exposure)
  • Neurological disorder (e.g. epilepsy, neurodegenerative disorder)
  • Serious mental illness (e.g. schizophrenia, bipolar disorder)
  • Suicidal ideation within the last month
  • Current (≤6 months) and/or heavy cigarette smokers (i.e. ≥ 10 pack-years)
  • Oral/nasal steroids or other intranasal medications
  • Immunomodulatory medications
  • Pregnant or trying to become pregnant

Study Design

Enrollment

60 participants

Anticipated

Intervention Model

Single group

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

experimental: Open Label Trigeminal Nerve Stimulation-enhanced Smell Training (TNS-enhanced ST)

TNS-enhanced ST will be administered at-home 5 days/week for 8 weeks. Participants will self-administer the first treatment of TNS-enhanced ST with the assistance and help of study staff. This includes attaching the gel pads to the forehead and turning the TNS system on for 30-min., training with different odorants and providing ratings on a website called REDCap, an easy-to-use, secure, internet-based data collection site.

Interventions

Trigeminal Nerve Stimulation-enhanced Smell Training

TNS is a form of cranial nerve stimulation that uses a simple transcutaneous electrical nerve stimulation device, and adhesive electrodes that are attached to forehead to deliver low-level electrical current. Stimulating the trigeminal nerve activates the trigeminal afferent sensory pathway and central brain regions where the intranasal trigeminal and olfactory circuits converge. Smell Training requires 4 odors to be smelled individually for 10 sec each and record ratings.

Primary outcome measure

  • Change in Psychophysical Olfactory Function from Baseline to 4 and 8 Weeks [ Time Frame: 8 weeks ]
  • Change in Perceived Intensity of Odorants from Baseline to 4 and 8 Weeks [ Time Frame: 8 weeks ]
  • Change in Perceived Hedonics of Odorants from Baseline to 4 and 8 Weeks [ Time Frame: 8 weeks ]
  • Change in Olfactory-related Quality of Life from Baseline to 4 and 8 Weeks [ Time Frame: 8 weeks ]
  • Change in Impact of Olfactory Loss from Baseline to 4 and 8 Weeks [ Time Frame: 8 weeks ]

Central Contacts and Locations

Central contacts

Bernadette Cortese, PhD

8437926922corteseb@musc.edu

Locations

Medical University of South Carolina

Recruiting

Charleston, South Carolina, United States, 29425

Contacts

Bernadette Cortese, Ph.D.

843-792-6922corteseb@musc.edu

More Information

Sponsor

Medical University of South Carolina

Last update posted

Aug 12, 2026

Last verified

Aug, 2026

Keywords

  • olfaction
  • smell loss
  • chronic rhinosinusitis
  • olfactory dysfunction
  • smell training
  • olfactory training
  • trigeminal nerve stimulation
  • sensory loss

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Medical University of South Carolina on 2026-08-12.