Collecting small nasal tissue samples to examine smell-sensing cells

Analysis of Human Olfactory Biopsies

Not applicable Interventional Duke University · NCT07021040

This project will collect small nasal tissue samples to test how smell-sensing cells work in people with normal smell, smell loss, or Alzheimer's.

Quick facts

PhaseNot applicable
Study typeInterventional
Enrollment125 (estimated)
Ages18 Years and up
SexAll
SponsorDuke University Academic / other
Locations1 site (Durham, North Carolina)
Trial IDNCT07021040 on ClinicalTrials.gov

What this trial studies

This prospective study collects olfactory lining tissue from the nasal cavity of healthy adults and people with conditions that can affect smell, including Alzheimer's, post-viral smell loss, inflammatory sinonasal disease, and aging. Participants will undergo standard psychophysical smell testing and some may briefly sniff specific odors to stimulate olfactory cells before tissue collection. Biopsies are obtained in the otolaryngology clinic or during unrelated endoscopic nasal surgery using a punch technique or a cytology brush. Samples are processed in the investigator's lab for histology, primary cell culture, flow cytometry, and transcriptomic assays including RNA-seq/act-seq to characterize cell populations and activity.

Who should consider this trial

Good fit: Adults who can provide informed consent and tolerate nasal endoscopy/biopsy, including people aged 18–80 with normal smell, documented smell dysfunction (such as post-viral or inflammatory causes), or preclinical or symptomatic Alzheimer's.

Not a fit: People with advanced dementia who cannot consent, active rhinosinusitis or other sinonasal conditions that preclude safe biopsy, prior surgeries or tumors affecting the olfactory region, Parkinson's disease, allergies to required topical agents, inability to complete nasal procedures, or inability to read/speak English are excluded and unlikely to benefit from participation.

Why it matters

Potential benefit: If successful, this work could improve understanding of the cellular changes that cause smell loss and identify tissue-based markers relevant to Alzheimer's and other olfactory disorders, helping guide future diagnostics or treatments.

How similar studies have performed: Small studies using olfactory biopsy and transcriptomic profiling have characterized cellular changes in smell loss and neurodegeneration, but large-scale act-seq profiling in Alzheimer's-related olfactory tissue is still relatively novel.

Eligibility criteria

Show full inclusion / exclusion criteria
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

Where this trial is running

Durham, North Carolina

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Alzheimer DiseaseSmell LossSmell Dysfunctionact-seqnasal biopsyRNA-seq
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.