Recruiting
Phase 1
Phase 2

Rifaximin

Sponsor:

Jasmohan Bajaj

Code:

NCT06718686

Conditions

Dementia Alzheimer Type

Dementia Associated With Cerebrovascular Disease

Eligibility Criteria

Sex: All

Age: 65+

Healthy Volunteers: Not accepted

Interventions

Rifaximin SSD 40 mg IR tablet

Placebo

Study Details

Brief summary:

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.

Conditions

Dementia Alzheimer Type

Dementia Associated With Cerebrovascular Disease

Study ID

NCT06718686

Start date

Dec 30, 2024

Status verified date

Apr, 2026

Completion date

Dec 30, 2027

Anticipated

Primary completion date

Oct 30, 2027

Anticipated

Eligibility Criteria

Eligibility Criteria

Sex: All

Age: 65+

Healthy Volunteers: Not accepted

Inclusion Criteria:

  • 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.

Exclusion Criteria:

  • Dementia not due to AD or VaD
  • Clinically significant agitation or aggression (requiring treatment with antipsychotic medication)
  • Delusions and/or hallucinations
  • Severe psychopathology including major depression
  • 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.
  • Diarrhea
  • Hypersensitivity to rifaximin, components of rifaximin,
  • and any rifamycin antimicrobial agent
  • 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.
  • History of alcohol and/or drug abuse
  • Participation in another investigational drug trial in the last 30 days

Study Design

Enrollment

20 participants

Anticipated

Intervention Model

Sequential

Primary purpose

Treatment

Interventions and Outcome Measures

Arms

placebo comparator: Placebo

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

experimental: Rifaximin SSD 40mg IR BID

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

Interventions

Rifaximin SSD 40 mg IR tablet

Drug therapy vs placebo

Placebo

Placebo drug

Primary outcome measure

  • Change in stool and serum short-chain fatty acid levels [ Time Frame: 10 weeks ]
  • Change in bile acids in stool and serum [ Time Frame: 10 weeks ]

Central Contacts and Locations

Central contacts

Jasmohan S Bajaj, MD

804-675-5802jasmohan.bajaj@vcuhealth.org

Haley Obolewicz, RN

804-675-5705haley.obolewicz@va.gov

Locations

Richmond VA Medical Center

Recruiting

Richmond, Virginia, United States, 23249

Contacts

Haley Obolewicz, RN

804-675-5000haley.obolewicz@va.gov

More Information

Sponsor

Jasmohan Bajaj

Last update posted

Apr 3, 2026

Last verified

Apr, 2026

Keywords

  • dementia
  • rifaximin
  • gut-brain
  • Alzheimer's
  • vascular dementia

Trial information was received from ClinicalTrials.gov and was last updated on 2026-09-10. This information was provided to ClinicalTrials.gov by Jasmohan Bajaj on 2026-04-03.