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Taking people in FranceNo phase

Testing stool samples for markers of Alzheimer's disease

Studies stool samples for amyloid and tau proteins to help detect Alzheimer's disease.

Key facts

Who runs it
University Hospital, Grenoble
Where
Grenoble, FranceSee the site
Trial code
Registry title
Validation of an Alzheimer's Disease Marker by Fecal Assay of Amyloid Peptides and Tau Proteins
Status
Recruiting
People taking part
115 people, planned
Started
11 Oct 2024
Expected to end
6 Oct 2027
Type of study
Observational, 5 groups
Treatments tested
  • faecal analysis
Record updated
5 May 2026

Who can take part

AI summary

From the trial's eligibility criteria. Machine-read from the registry text on this page, so it can be wrong. The registry text below and the trial team decide who can take part.

The trial is looking for adults aged 40 or older who either have Alzheimer's disease, have memory or thinking problems without Alzheimer's disease, or are healthy volunteers. It tests a stool test for Alzheimer's disease.

Age
At least 40 years
Sex
Men and women can join.
Disease stage
People with Alzheimer's disease at the stage of minor or major cognitive impairment (according to IWG 2021 criteria). Also people with minor or major cognitive impairment without Alzheimer's disease, and healthy volunteers with no cognitive complaints (MMSE 26 or more, CDR 0).
Biomarker or test result
People with Alzheimer's disease must be A+ T+. Others with cognitive impairment have negative (A- T-) or mixed (A+ T- or A- T+) CSF results for Alzheimer's markers.

Main reasons for not taking part

  • Cannot understand the study instructions or give informed non-opposition
  • Not covered by social security or a similar scheme
  • Legally protected adults or people under administrative or judicial supervision

The registry criteria, word for word

Show all 30 criteriaShow less

Who can take part

  • For subjects with Alzheimer's disease MA TCM (A+ T+):
  • Subjects diagnosed with AD according to IWG 2021 criteria
  • Subject at the stage of major cognitive impairment
  • At least 40 years of age
  • Presence of a caregiver or support person
  • No informed opposition; For subjects with AD TCm (A+ T+):
  • Subject diagnosed with AD according to IWG 2021 criteria
  • Subject at the stage of minor cognitive impairment
  • Minimum age 40
  • No informed opposition For subjects with minor or major cognitive impairment who do not have AD TC Non-AD LCR negative (A- T-)
  • Subject at stage of minor or major cognitive impairment
  • CSF negative (A-T-) for Alzheimer's disease biomarkers: A-T- according to ATN classification
  • Minimum age 40
  • No informed objection and TCm CSFdiscordant (A+ T-) or (A- T+):
  • Subject at stage of minor cognitive impairment
  • CSF discordant (A-T+ or A+T-) with Alzheimer's disease biomarkers
  • Minimum age 40
  • No informed opposition; For healthy volunteers (VS) :
  • No cognitive complaints
  • MMSE ≥ 26
  • CDR 0
  • Minimum age 40
  • No informed opposition

Who cannot take part

  • For MA TCM (A+ T+), MA TCm (A+T+) and TC Non MA LCR negatif (A-T-) and TCm LCRdiscordant (A+ T-) or (A- T+):
  • Inability to understand search instructions or to give informed non-opposition
  • Absence of social security affiliation or plan
  • Persons covered by articles L1121-5 to L1121-8 of the CSP (legally protected adult, subject under administrative or judicial supervision); For healthy volunteers:
  • Incapacity to understand research instructions or to give informed non-opposition
  • Persons covered by articles L1121-5 to L1121-8 of the CSP (legally protected adult, subject under administrative or judicial supervision)
  • Absence of social security affiliation or of such a scheme

Where in France

  • Grenoble Alpes University HospitalGrenoble, FranceContact: Sandrine KEIGNARTTaking people

About the trial

What the trial wants to find out

Alzheimer's disease (AD) is the leading cause of dementia in humans, currently affecting almost one million people in France. It results from an irreversible degeneration of neurons responsible for a progressive decline in the main cognitive and memory functions due to a cerebral accumulation of plaques containing fibrillary amyloid peptide (Aβ) and neurofibrillary tangles composed of truncated, hyperphosphorylated tau protein (pTau).

Read full original descriptionShow less

There is currently no curative treatment for this disease in France. However, two treatments aimed at reducing beta-amyloid plaques in the brain have been approved by the U.S. Food and Drug Administration. The failure of the latest therapeutic strategies is largely due to the fact that the disease is diagnosed too late, starting with a long asymptomatic phase, which is the one that needs to be targeted in order to prevent irreversible neurodegenerative mechanisms.

The development of diagnostic tools is gradually making it possible to detect such a sequence, but this has its drawbacks (radioactive load, invasive procedure, cumbersome set-up).

Over the last ten years, research has focused on the development of plasma or salivary markers. Although encouraging, these studies show either a lack of sensitivity or reproducibility, or a lack of specificity or precocity.

The expression of Aβ and Tau proteins has recently been demonstrated in the enteric nervous system and enterocytes. Intestinal Aβ is involved in various gut functions and regulation.

What recent work by investigators demonstrates is the essential and hitherto unrecognized role of the gut-brain axis in maintaining brain homeostasis. In a mouse model of AD, the investigators have demonstrated a mechanism for intestinal elimination (clearance) of toxic brain forms of Tau and Aβ proteins, via the lymphatic network.

The clearance of cerebral Tau and Aβ proteins in the stool may constitute a reliable and powerful diagnostic signature of AD. Its study would represent a new, non-invasive and easily accessible technique for the early diagnosis of AD in humans.

The 5 groups in the trial

  • 35 MA TCM (A+ T+)

    Group of patients with established Alzheimer's disease at the stage of major cognitive impairment

    Treatment: faecal analysis

  • 15 MA TCm (A+ T+)

    Group of patients with established Alzheimer's disease at the stage of minor cognitive impairment

    Treatment: faecal analysis

  • 15 TC Non MA LCR negatif (A- T-)

    Group of patients with minor or major cognitive impairment but without AD

    Treatment: faecal analysis

  • 15 TCm LCRdiscordant (A+ T-) ou (A- T+)

    Group of patients with minor cognitive impairment and discordant CSF

    Treatment: faecal analysis

  • 35 VS

    Group of healthy volunteers

    Treatment: faecal analysis

Questions to ask the study team

  1. How often do I need to come in, and for how long each time?
  2. Are travel costs paid?
  3. Can I keep my own doctor?
  4. What happens if I want to stop?

Contact the study team: see the registry record → Contacts and Locations

Print a page for my doctor

Data and sources

Registry record
Listed on ClinicalTrials.gov.
Official title
Validation of a Diagnostic and/or Prognostic Marker for Alzheimer's Disease by Fecal Determination of Amyloid Peptides and Tau Proteins
Plain-language title
Testing stool samples for markers of Alzheimer's diseaseGenerated from the registry record. The registry title is the official one.
AI summary
From the trial's eligibility criteria. Read by machine on 12 November 2026.
Record updated
5 May 2026