Phase 4
N=25
Preventing Recurrent UTI With Vaginal Estrogen
Recurrent Urinary Tract Infection · Urinary Tract Infections · Cystitis Recurrent
Bottom Line
View on ClinicalTrials.gov: NCT05551949 ↗Enrolled (actual)
25
Serious AEs
0.0%
Results posted
Mar 2026
Primary outcome: Primary: Change in Vaginal Microbiota — 2.75 change in percent relative abundance
Study Design & Population
- Study type
- Interventional
- Phase
- Phase 4
- Interventions
- Vaginal estradiol tablets (Drug)
- Age
- Adult, Older Adult · 55+ yrs
- Sex
- Female
- Sponsor
- Johns Hopkins University
- Primary completion
- Jun 2025
Outcome Measures
| Outcome | Result | p-value |
|---|---|---|
| PRIMARY Change in Vaginal Microbiota |
2.75 | — |
| PRIMARY Change in Vaginal Interleukin-6 Level |
-58.66 | — |
| PRIMARY Change in Urinary Microbiota |
-3.50 | — |
| PRIMARY Change in Urinary Interleukin-6 Level |
-476.10 | — |
| SECONDARY Urinary Tract Infection Recurrence |
7 | — |
Summary
Among postmenopausal women who suffer from recurrent urinary tract infections (UTI), vaginal estrogen therapy prevents UTI recurrences for 50% of sufferers. This research will investigate why some women benefit but others do not, focusing on (a) the effects of vaginal estrogen therapy on the bacteria that inhabit the vagina and bladder, (b) its influence on immune responses in both compartments, and (c) the extent to which those changes are critical to successful UTI prevention. The findings will be a first step in the development of more effective strategies to prevent UTI, one of the most common and costly benign urologic conditions.
Eligibility Criteria
Inclusion Criteria
Participants in this study will be
- Postmenopausal women (menopausal for at least 1 year)
- Minimum age of 55 years
- Participants will have documentation of recurrent UTI, defined as follows:
- History of treatment for at least 3 UTIs in the past year or 2 episodes within 6 months AND
- At least one positive urine culture during an acute symptomatic episode.
Exclusion Criteria
- Women receiving antibiotic prophylaxis to prevent UTI recurrence;
- Women with contraindications to vaginal estrogen (as indicated on the FDA-mandated package insert) and those who have used vaginal or systemic estrogen within the past 6 months;
- Women with an active UTI and those who have received antibiotics within the prior 2 weeks;
- Women with complicated rUTI, defined by immune compromise, anatomic or functional abnormalities of the urinary tract, indwelling catheterization, those performing self-catheterization, and those with neurological disease or illness relevant to the lower urinary tract;
- Women with only asymptomatic bacteriuria (rather than recurrent symptomatic UTI)
Data sourced from ClinicalTrials.gov (NCT05551949). Outcome figures and adverse-event rates are extracted automatically from the registry's posted results and are provided for clinician reference, not as a substitute for the primary publication.