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NCT03336437 · ClinicalTrials.gov registry record · Phase 4
Estrogen and the Urogenital Microbiome in GSM
A Phase 4 study, sponsored by Oregon Health and Science University.
- Completed
- Registry status
- Phase 4
- Development phase
- 40
- Enrollment target
NCT03336437: Completed Phase 4 study, sponsored by Oregon Health and Science University.
NCT03336437 is a Phase 4 study that has completed, run by Oregon Health and Science University. The registered enrollment target is 40 participants, below the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (92% lower). According to ClinicalTrials.gov, the official US trial registry.
The verdict
NCT03336437, a Phase 4 study, has completed, sponsored by Oregon Health and Science University.
- COMPLETED
- Registry status
- Phase 4
- Development phase
- 40 participants
- Enrollment target
Study Summary
This is a study of how local estrogen treatment affects the microbiome of the vagina and bladder in postmenopausal women experiencing symptoms as part of "Genitourinary Syndrome of Menopause." The goal is to understand more about the underlying microbial changes occurring in menopause and whether these are reversible with estrogen.
Primary Outcome
Investigators will collect catheterized urine samples from participants at time of enrollment in the study and again after 12 weeks of their assigned vaginal ring intervention. Bacteria will be extracted from the urine and the resident microbial community will be characterized by amplifying the bacterial 16S ribosomal RNA gene via PCR. The de-identified samples containing amplified 16S DNA will be sequenced using Illumina MiSeq. The genetic sequences will be processed to generate a table of bact
Interventions
- DRUG Estradiol vaginal ring
- OTHER Placebo vaginal ring
Trial Details
| Field | Value |
|---|---|
| Enrollment Target | 40 participants |
| Start Date | 2018-02-01 |
| Est. Completion | 2019-08-23 |
| Phase | Phase 4 |
What the finished NCT03336437 record still lists
NCT03336437 is an interventional study that assigns participants to a tested intervention. The registry caps enrollment at 40 participants, a relatively small participant target, below the 518-participant average among 9,235 other Phase 4 trials with a reported enrollment target (92% lower).
The record links to 0 conditions, and to 2 interventions - of which Estradiol vaginal ring is the first listed.
NCT03336437 does not publish any study locations in the registry export this page uses.
Frequently Asked Questions
What is clinical trial NCT03336437 about?
NCT03336437 is a clinical study titled "Estrogen and the Urogenital Microbiome in GSM". This is a study of how local estrogen treatment affects the microbiome of the vagina and bladder in postmenopausal women experiencing symptoms as part of "Genitourinary Syndrome of Menopause." The goal is to understand more about the underlying microbial changes occurring in menopause and whether th...
What is the current status of trial NCT03336437?
This trial is currently completed. It is a Phase 4 study. The enrollment target is 40 participants. The study started on 2018-02-01. Estimated completion is 2019-08-23.
What interventions are being tested in trial NCT03336437?
The interventions under investigation include: Estradiol vaginal ring (DRUG), Placebo vaginal ring (OTHER).
Who is sponsoring clinical trial NCT03336437?
This trial is sponsored by Oregon Health and Science University, which has 546 total clinical trials registered on ClinicalTrials.gov.
Learn More About Clinical Trials
How this trial's enrollment target compares
Where NCT03336437's enrollment target sits among peer trials
40 1397th of 2000 higher than 533 of 2,000 other Phase 4 trials
participants (enrollment target), bucketed by value
Each bar is a band; taller bars hold more other Phase 4 trials. The dashed line + filled bar mark this entry. Hover or tap any bar for its full count and share, and where it sits relative to this entry.
Source ClinicalTrials.gov registry export · 2026-08-08
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