Recurrent UTIsDmannoseRCTNCT06940622
A Trial of D-mannose for the Prophylaxis of Recurrent Urinary Tract Infections
A study testing D-Mannose in people with Recurrent UTIs and Recurrent Urinary Tract Infections, run by University of Texas Southwestern Medical Center at 1 site in United States.
Trial summary
A randomized, double-blind, placebo-controlled, 12-month study to determine the effectiveness of D-mannose (2g daily) supplementation in rUTI (recurrent urinary tract infection) prevention in post-menopausal women. Read more about this study
- Who is it for?
- Ages 55 to 85 years, women only
- Conditions the study is for
- Recurrent UTIs, Recurrent Urinary Tract Infections, Recurrent Urinary Tract Infections in Women
- What is being tested?
- D-Mannose
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 90 participants
- Where
- 1 siteUnited States
- Study dates
- 1 Aug 2025to 30 Sep 2030
- Phase
- Interventional
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 55 to 85 years
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Female, post-menopausal, age ≥ 55 years old
- Diagnosis of recurrent UTI, defined as ≥ 3 symptomatic culture-proven UTI episodes in 12 months or ≥ 2 in 6 months.
- Currently free from a UTI determined based on absence of symptoms as determined by the UTI symptom assessment questionnaire79 and negative urine culture (<103 colony forming units per ml of urine).
- Able to attend all follow-up appointments for the study.
- A negative upper and lower urinary tract evaluation, including pelvic examination for pelvic organ prolapse (less than stage 2), measurement of post-void residual (less than 50 ml), and imaging (renal ultrasound and standing voiding cystourethrogram) to exclude kidney stone, hydronephrosis, reflux, or urethral diverticulum.
Who cannot join
- Current use of D-mannose. Patients willing to stop taking D-mannose will be offered to join the trial after a 4-week wash-out period.
- Complicated UTIs, including need for catheter drainage or intermittent catheterization, neurogenic bladder, bladder augmentation, or urinary diversion.
- Ongoing supplement use (Box 1). Patients willing to stop taking the listed supplements will be offered to join the trial after a 4-week wash-out period.
- Evidence of upper tract infection (pyelonephritis), including temperature higher than 38°C, flank/lumbar pain or tenderness
- Diagnosis of interstitial cystitis or overactive bladder syndrome
- Prophylactic antibiotics started in the last 3 months and unwilling to discontinue, or intention to start in the next 12 months
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- Use of Uromune or other vaccine approaches to reduce rUTI
- Participation in a research study involving an investigational product in the past 12 weeks
- Receipt of phage treatment
- History of chronic diarrhea requiring regular therapy
- Inability to swallow or known history of gastrointestinal malabsorption
- History of recurrent vaginal yeast infections
- Systemic disease precluding enrollment in this study (uncontrolled diabetes with HgA1C above 7, ongoing chemotherapy or immunotherapy, renal insufficiency [creatinine > 1.5 g/dl]), mental or cognitive impairment, weight loss diet requiring excessively large amounts of fluid intake, or other health-related specific diet).
- Nursing home resident
- BMI >40
- Box 1 Supplements to avoid
- Multi-Vitamins and Multi-Mineral capsules
- Specific Vitamins or Minerals (e.g., Calcium, Citrical, Calcium Gummies, Vitamin A, D, Niacin, Pyridoxine, Selenium, Vitamin E, B6, Iron, Omega 3, D3, Magnesium, B-Complex, Women's Ultra MultiVitamin, GNC B-Complex, B-12, PreserVision Areds2, Vitamins D, B Pollen)
- Probiotics
- Cranberry Mannose or Cranberry Extract Weight loss products to avoid
- Medifast
- Vitafusion
- OptiVin Products
- Appetite Suppressants
- Keto-Fuel
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
University of Texas Southwestern Medical Center
Dallas, Texas, 75390
Sonobia Garrett, BSHS, 214-645-8787, sonobia.garrett@utsouthwestern.edu
philippe.zimmern@utsouthwestern.edu
About this study
Official title: A Randomized Controlled Trial of D-mannose for the Prophylaxis of Recurrent Urinary Tract Infections in Post-menopausal Women
A randomized, double-blind, placebo-controlled, 12-month study to determine the effectiveness of D-mannose (2g daily) supplementation in rUTI (recurrent urinary tract infection) prevention in post-menopausal women.
Read the detailed description
The proposed study on D-mannose prophylaxis is designed to address a critical unmet medical need to improve the understanding and prevention of rUTI (recurrent urinary tract infection) in post-menopausal women, a population disproportionately affected by rUTI and understudied. The efficacy of D-mannose on preventing uncomplicated rUTI will be elucidated, and additional study measures (including urine culture and one-hour D-mannose test results) may help establish an ideal candidate for responding to daily D-mannose intake over time. The proposed study will follow CONSORT guidelines for randomized clinical trial studies.
Aim 1. Test the hypothesis that D-mannose provides effective rUTI prophylaxis in post-menopausal women over 6 months.
Aim 2. Test the hypothesis that D-mannose provides effective rUTI prophylaxis in post-menopausal women beyond 6 months and up to one year.
The overarching hypotheses are that (1) D-mannose will be found superior to placebo in preventing rUTI in post-menopausal women over 6 months as suggested by one prior RCT7 (Aim 1) and (2) D-mannose will remain effective for rUTI prophylaxis up to one year (Aim 2).
Ninety (90) women currently UTI-free and with a history of uncomplicated rUTI, defined as ≥ 2 symptomatic UTIs in 6 months or ≥ 3 symptomatic UTIs in 12 months, will be enrolled and randomized (2:1 ratio) to receive D-mannose (2g, i.e., 4 x 500mg capsules) or placebo daily for 12 months.
- Conditions
- Recurrent UTIs, Recurrent Urinary Tract Infections, Recurrent Urinary Tract Infections in Women, Recurrent Urinary Tract Infection, Cystitis Recurrent, Cystitis Chronic
- Being tested
- D-Mannose, Placebo
- Keywords
- D-mannose, dmannose, uti, ruti, recurrent urinary tract infection, urinary tract infection, cystitis, chronic uti, chronic cystitis
- Medical subject headings
- Urinary Tract Infections, Cystitis
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
D-MannoseDietary supplement
D-mannose (2g, i.e., 4 x 500mg capsules) daily for 12 months.
PlaceboDietary supplement
Placebo daily for 12 months.
| Study group | Role | What they receive |
|---|---|---|
| D-mannose | Active comparator | Dietary Supplement: D-Mannose Receives: Dietary Supplement: D-Mannose |
| Placebo | Placebo comparator | Dietary Supplement: Placebo Receives: Dietary Supplement: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Failure rate
To determine whether prophylaxis with D-mannose reduces the incidence of UTI episodes compared to placebo. "Failure rate," defined as having 2 UTIs in 6 months or 3 in one year.
Measured: Through study completion, an average of 5 years
Secondary outcomes (3)
Number of UTI antibiotic treatments
To investigate if D-mannose reduces the need for antibiotic use due to recurrent UTIs (measured as number of antibiotic courses for symptomatic culture-proven UTI episodes) compared to placebo.
Number of UTI antibiotic treatments during the 6 months of treatment. If the participant receives >1 antibiotic course for UTI without symptom relief, it is regarded as one episode and counted as one antibiotic treatment. If there has been an asymptomatic period of at least 14 days in between two UTI antibiotic courses, this will be regarded as a new antibiotic treatment.
Measured: Through study completion, an average of 5 years
Symptom severity
To investigate if D-mannose reduces the severity of UTI symptoms compared to placebo. Record symptom severity using a validated UTI symptom assessment questionnaire.
Measured: Through study completion, an average of 5 years
Serious adverse events associated with D-mannose
To determine the frequency of serious adverse events associated with D-mannose. Number of participants who experienced adverse events >= Grade 3, as defined by Common Terminology Criteria for Adverse Events by CTCA version 5.0.
Measured: Through study completion, an average of 5 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted23 Apr 2025
- Study start1 Aug 2025
- Primary completion30 Sep 2029 (estimated)
- Study completion30 Sep 2030 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Recurrent UTIsStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- D-mannose and placebo
- Masking
- Quadruple blind
- Who is masked
- Participant, Care provider, Investigator, Outcomes assessor
- Enrolment
- 90 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of Texas Southwestern Medical Center
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Philippe Zimmern, University of Texas Southwestern Medical Center
- Investigators
- Philippe Zimmern, MD, Principal investigator, University of Texas Southwestern Medical Center
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06940622
- Sponsor's protocol ID
- STU-2024-1090
- Acronym
- DmannoseRCT
- Status last verified
- Sep 2025
- First submitted
- 11 Apr 2025
- Last updated
- 22 Sep 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No