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Taking people in United StatesPhase 1/2

Tests rifaximin, an antibiotic, in people with dementia

Tests whether rifaximin affects gut microbes in adults 65 or older with dementia.

Key facts

Who runs it
Jasmohan Bajaj
Where
Richmond, United StatesSee the site
Trial code
Registry title
Rifaximin SSD in Dementia Trial
Status
Recruiting
Phase
Phase 1/2
People taking part
20 people, planned
Started
30 Dec 2024
Expected to end
30 Dec 2027
Type of study
Interventional, 2 groupsOne group gets a placebo (a dummy treatment), for comparison.
Treatments tested
  • Rifaximin SSD 40 mg IR tablet
  • Placebo
Record updated
3 April 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 65 or older with mild or moderate Alzheimer's disease or vascular dementia who live at home with a caregiver.

Age
65 years or older
Sex
Men and women can join.
Disease stage
Probable Alzheimer's disease or vascular dementia, mild or moderate, based on the Clinical Dementia Rating Scale.
Earlier treatment
No antibiotic use in the prior 6 months. No other investigational drug trial in the last 30 days.

Main reasons for not taking part

  • Dementia not caused by Alzheimer's disease or vascular dementia
  • Agitation or aggression needing antipsychotic medication, or delusions or hallucinations
  • Severe mental illness including major depression
  • Diarrhea, or allergy to rifaximin or any rifamycin antibiotic
  • History of alcohol or drug abuse

The registry criteria, word for word

Show all 19 criteriaShow less

Who can take part

  • Probable Alzheimer's Disease (AD) or Vascular Dementia (VaD) mild or moderate based on Clinical Dementia Rating Scale
  • Males and Females Age ≥ 65 years
  • Community living with availability of caregiver to accompany participant to study visits and to participate in the study
  • Able to consent or legal guardian who can consent (with participant assent)
  • Legally authorized representative (LAR) and caregiver for the study is the same individual
  • Fluency (both participant and caregiver) in written and spoken English to participate in study visits

Who cannot take part

  • Clinically significant agitation or aggression (requiring treatment with antipsychotic medication)
  • Antibiotic use in the prior 6 months
  • Taking medications that interact with Rifaximin. P-glycoprotein (P-gp) inhibitor treatment is permitted as long as the use of P-gp inhibitors is discussed with the investigator
  • Participation in another investigational drug trial in the last 30 days
  • Dementia not due to AD or VaD
  • Unstable, severe, or poorly controlled medical conditions evident from physical examination or clinical history
  • Visual and/or hearing disorder that prevents completion of neuropsychologic evaluations
  • Hypersensitivity to rifaximin, components of rifaximin,
  • History of alcohol and/or drug abuse
  • Delusions and/or hallucinations
  • Severe psychopathology including major depression
  • Diarrhea
  • and any rifamycin antimicrobial agent

Where in United States

  • Richmond VA Medical CenterRichmond, United StatesContact: Haley Obolewicz, RNTaking people

About the trial

What the trial wants to find out

Using a new formulation of rifaximin, a non-absorbable antibiotic, to test if it can affect microbes in the gut of patients with dementia favorably.

The 2 groups in the trial

  • PlaceboPlacebo, for comparison

    Patients will be given placebo and actual drug sequentially with the order hidden

  • Rifaximin SSD 40mg IR BIDTreatment being tested

    Patients will be given placebo and actual drug sequentially with the order hidden

    Treatment: Rifaximin SSD 40 mg IR tablet

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
Rifaximin in Dementia Trial (RIDE): Gut-Brain Modulation With Rifaximin SSD in Dementia
Plain-language title
Tests rifaximin, an antibiotic, in people with dementiaGenerated 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
3 April 2026