Recruiting

Observational Study

Sponsor:

Duke University

Code:

NCT07021040

Conditions

Alzheimer Disease

Smell Loss

Smell Dysfunction

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Interventions

olfactory testing

Odor stimulation

Olfactory biopsy

Study Details

Brief summary:

This research study aims to investigate the function of the olfactory lining in the nasal cavity and its potential alterations in both healthy and diseased conditions. The olfactory lining is involved in the sense of smell.

The purpose of this study is to collect tissue from the nasal cavity.

Conditions

Alzheimer Disease

Smell Loss

Smell Dysfunction

Study ID

NCT07021040

Start date

Jan 6, 2025

Status verified date

Jun, 2026

Completion date

Jul 31, 2029

Anticipated

Primary completion date

Apr 30, 2029

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 18+

Healthy Volunteers: Not accepted

Group 1: Alzheimer's study

Inclusion Criteria:

  • Between the ages of 18 and 80
  • Pre-clinical AD (this cohort consists of subjects who have normal cognitive testing and function, but have positive AD biomarkers);
  • Symptomatic AD (a confirmed diagnosis of Alzheimer's or dementia who are capable of understanding and signing the consent document)

Exclusion Criteria:

  • Advanced Alzheimer's/dementia
  • Self-reported or known allergy to Afrin or Tetracain HCL (or related class of drugs)
  • Active Rhinosinusitis symptoms
  • Other known sinonasal disease history that would preclude biopsy (i.e prior sinus or skull base surgery directly impacting this anatomic region, sinonasal neoplasm in this anatomic region, olfactory cleft polyps)
  • Parkinson's disease
  • Unable or willing to complete the nasal endoscopy procedure.
  • Unable to read or speak English
  • Unable to provide legally effective consent

Group 2: Act-seq study or Non-AD controls

Inclusion Criteria:

  • Age 18 years or older
  • Patients being seen for rhinology or olfactory disorders
  • Patients having unrelated endoscopic nasal surgery

Exclusion Criteria:

  • Self-reported or known allergy to Afrin or Tetracain HCL (or related class of drugs)
  • Unable or willing to complete the nasal endoscopy procedure
  • Unable to read or speak English
  • Unable to provide legally effective consent

Study Design

Enrollment

125 participants

Anticipated

Intervention Model

Parallel Assignment

Primary purpose

Basic Science

Interventions and Outcome Measures

Arms

other: Alzheimer's study

Olfactory function will be assessed using the Smell Identification Test (SIT, Sensonics, Inc) or Sniffin' Sticks Test. Using topical intranasal decongestion/anesthetic (oxymetazoline/lidocaine), a cytology brush biopsy will be obtained from the olfactory cleft region of the nose in clinic exam room using a nasal endoscope.

other: Act-seq study or Non-AD controls

Olfactory function will be measured using established psychophysical testing via the Smell Identification Test or Sniffin' Sticks. Researchers will obtain biopsies from (1) normosmic subjects with or without odor stimulation, and (2) hyposmic subjects with history of upper respiratory infection (URI) as likely cause of the smell loss (such as COVID19) with or without odor stimulation.

Interventions

olfactory testing

Patients will undergo smell testing, using the Smell Identification Test (Sensonics), a validated widely-used 40-item "scratch-and-sniff" style psychophysical test to determine olfactory function.

Odor stimulation

subset of patients will be asked to sniff a specific odor for about an hour, using commercially available "odor pens" (Sniffin' Sticks or Sensonics). These odor pens are widely used for olfactory training therapy, a treatment designed to help people with some forms of smell loss; they are also used in psychophysical olfactory testing.

Olfactory biopsy

Biopsy involves a simple cytology brush technique of the lining of the nose in a region called the olfactory cleft, using a nasal endoscope, and can be done in clinic or in the operating room at the time of a nasal surgery. Topical oxymetazoline and tetracaine spray is applied to the nasal cavity, a rigid nasal endoscopy (0-degree 4 mm endoscope, Karl Storz) is performed to visualize the olfactory cleft, and a small nasal cytology brush biopsy (Hobbs Medical)is performed by swabbing and rotating brush gently in the olfactory cleft. Cytology sample is placed into a buffer (Hibernate-E, Thermo Fisher)on ice for transport to the research lab.

Primary outcome measure

  • Transcription state changes in olfactory cells [ Time Frame: study is planned for completion over 5 years ]

Central Contacts and Locations

Central contacts

Locations

Duke University Health Center

Recruiting

Durham, North Carolina, United States, 27710

Contacts

Principal Investigator:

Bradley J Goldstein, MD, PhD

More Information

Sponsor

Duke University

Last update posted

Jun 12, 2026

Last verified

Jun, 2026

Keywords

  • act-seq
  • nasal biopsy
  • RNA-seq

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-09. This information was provided to ClinicalTrials.gov by Duke University on 2026-06-12.