Cystitis, RecurrentPhase 4microbiomeNCT07186465
Microbiome-Modulating Prophylaxis RCT: Antibiotic vs Gynoflor in Postmenopausal Women With Recurrent Cystitis
A Phase 4 study testing Nitrofurantoin and Gynoflor in people with Cystitis, Recurrent and Urinary Tract Infections, run by Mahidol University at 1 site in Thailand.
Trial summary
This open-label, parallel-group randomized controlled trial compares two prophylaxis strategies for recurrent urinary tract infection (rUTI) in postmenopausal women: (1) nightly oral nitrofurantoin 100 mg for 6 months versus (2) a vaginal tablet containing Lactobacillus with ultra-low-dose estriol (Gynoflor: nightly… Read more about this study
- Who is it for?
- Ages 40 years and older, women only
- Conditions the study is for
- Cystitis, Recurrent, Urinary Tract Infections
- What is being tested?
- Nitrofurantoin and Gynoflor
- Type of treatment
- Pill or oral medicine
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 100 participants
- Where
- 1 siteThailand
- Study dates
- 11 Sep 2025to 30 Aug 2026
- Phase
- Phase 4
- Are there results?
- Not yet: the study is under way
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 40 years and older
- Women only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Female, postmenopausal, age ≥40 years
- Clinical history of recurrent urinary tract infection (rUTI) as assessed by the investigator
- Able and willing to take assigned prophylaxis for 6 months
- Able to attend baseline and Month 6 study visits and provide urine samples
- Able to provide written informed consent
- Willing and able to complete twice-weekly phone/LINE follow-ups
Who cannot join
- Current symptomatic UTI at enrollment (may be treated and reconsidered after resolution)
- Known hypersensitivity or contraindication to nitrofurantoin or to the Lactobacillus/estriol vaginal tablet (Gynoflor) or their excipients; significant renal impairment or other label-based contraindications to nitrofurantoin per local practice
- Planned urologic surgery or procedure expected during the 6-month study period
- Recent bacterial vaginosis (e.g., within the past month) or active vulvovaginal skin disorders precluding vaginal product use
- History of hormone-dependent malignancy (e.g., breast, uterine, or cervical cancer) or unexplained abnormal vaginal bleeding
- Significant liver disease (e.g., active hepatitis) or other conditions judged by the investigator to make participation unsafe
- Participation in another interventional trial that could interfere with outcomes
- Withdrawal of consent or severe adverse event requiring discontinuation
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Thailand1 site, 1 recruiting
- Recruiting
Faculty of Medicine Ramathibodi Hospital Mahidol University
Bangkok, Phayatai Ratchathewi, 10400
Lappanawat Santitham, 0944314994, cambellabios@gmail.com
About this study
Official title: Evaluating Urinary Microbiome Modulation :An RCT of Antibiotic vs Gynoflor Prophylaxis in Postmenopausal Women With Recurrent Cystitis
This open-label, parallel-group randomized controlled trial compares two prophylaxis strategies for recurrent urinary tract infection (rUTI) in postmenopausal women: (1) nightly oral nitrofurantoin 100 mg for 6 months versus (2) a vaginal tablet containing Lactobacillus with ultra-low-dose estriol (Gynoflor: nightly for 14 days, then twice weekly to month 6). Participants (≥40 years) are randomized 1:1 in computer-generated blocks and followed for 6 months. The primary endpoint is the proportion with rUTI recurrence within 6 months. Secondary endpoints include time to first recurrence, antibiotic resistance in breakthrough infections, change in lower urinary tract symptoms (Thai RUTISS), and urinary microbiome measures (Lactobacillus dominance and community diversity by qPCR and 16S rRNA). Key assessments occur at baseline and month 6 (urinalysis, culture, urinary microbiome sampling, and kidney function). Adherence and adverse events are captured via twice-weekly phone/Line contacts. Approximately 100 participants (50 per arm) will be enrolled as a feasibility-sized pilot.
Read the detailed description
Background and Rationale
Recurrent cystitis is common after menopause and burdens quality of life and healthcare use. Antibiotic prophylaxis is effective but may promote antimicrobial resistance with long-term use. Vaginal Lactobacillus with ultra-low-dose estriol can restore urogenital flora and potentially reduce rUTI and lower urinary tract symptoms. Comparative data versus nightly antibiotic prophylaxis-and effects on the urinary microbiome-remain limited. This trial directly evaluates clinical recurrence and microbiome modulation with nitrofurantoin versus a Lactobacillus/estriol vaginal tablet over 6 months.
Objectives
Primary objective: Compare the 6-month rUTI recurrence proportion between nitrofurantoin and Gynoflor.
Key secondary objectives: (a) time to first recurrence; (b) antimicrobial resistance patterns in breakthrough infections; (c) change in Thai RUTISS score; (d) Lactobacillus dominance and within-sample diversity of the urinary microbiome.
Key Endpoint Definitions
rUTI recurrence (primary): ≥1 symptomatic episode meeting clinical criteria with urine culture growth of a uropathogen during the 6-month follow-up (episodes during temporary treatment holds still count toward the endpoint).
Time to first recurrence: days from randomization to first qualifying rUTI.
Antibiotic resistance: susceptibility profile of cultured uropathogens from breakthrough infections, categorized per local laboratory standards.
Microbiome metrics: quantitative Lactobacillus abundance (qPCR) and alpha diversity indices from 16S rRNA profiling.
Design Overview
Open-label, two-arm, parallel RCT with 1:1 allocation by concealed, computer-generated block randomization. Follow-up is 6 months. Masking is not feasible due to intervention routes; laboratory personnel for microbiome and culture testing are shielded from allocation where practicable.
Interventions (Summary)
Nitrofurantoin arm: 100 mg orally once nightly through month 6.
Gynoflor arm: one vaginal tablet nightly for 14 days, then twice weekly (e.g., Monday/Friday) through month 6.
(Rescue treatment for symptomatic UTI follows standard of care; study prophylaxis resumes afterward to complete 6 months.)
Study Procedures (Selected)
Baseline (Day 0): consent, randomization, Thai RUTISS, urinalysis, urine culture, urinary microbiome sampling, BUN/creatinine.
Follow-up (Months 0-6): twice-weekly phone/Line check-ins to reinforce adherence and capture symptoms/adverse events; prompt clinical evaluation if UTI symptoms arise.
Month 6: repeat Thai RUTISS, urinalysis/culture, urinary microbiome sampling, BUN/creatinine.
Specimen handling: midstream clean-catch urine; UA ~20 mL, culture 5-10 mL, microbiome ~50 mL. Samples processed promptly or refrigerated at 4 °C ≤24 h if needed.
Laboratory Methods (Overview)
Urinary microbiome assays are performed at the Department of Medical Sciences: (1) qPCR estimating Lactobacillus abundance across time points; (2) 16S rRNA gene sequencing for community profiling and alpha diversity.
Sample Size and Analysis Plan (Pilot)
Approximately 100 participants (50/arm) are planned based on local feasibility for an initial pilot. Analyses will follow intention-to-treat with supportive per-protocol summaries. The primary endpoint will be compared between arms using a risk difference with 95% CIs and a chi-square or Fisher's exact test. Time-to-event data will be presented with Kaplan-Meier estimates and log-rank testing. Continuous outcomes (e.g., Thai RUTISS change) will use t-tests or Wilcoxon rank-sum as appropriate; paired pre/post within-arm changes will use paired tests. Missing outcome data will be handled by complete-case analysis with sensitivity analyses (e.g., worst-case imputation for the primary endpoint) if missingness >5-10%.
Safety Monitoring and Adherence
Expected risks include nitrofurantoin intolerance (e.g., GI upset, hypersensitivity), local vaginal irritation, minor phlebotomy discomfort, and time burden. Adverse events are solicited during twice-weekly contacts and at visits; serious adverse events are reported per IRB policy. Given the low-risk profile and pilot scope, a formal DSMB is not planned; the PI and study team review safety at regular intervals. Adherence is promoted by structured reminders and documented via participant report during check-ins.
Data Management and Quality
Case report forms are source-verified against electronic medical records and laboratory outputs. Microbiome and culture laboratories follow internal QC procedures; analytical staff are kept unaware of allocation when feasible. Randomization files are access-restricted; analysis is pre-specified prior to database lock.
- Conditions
- Cystitis, Recurrent, Urinary Tract Infections
- Being tested
- Nitrofurantoin, Gynoflor
- Keywords
- Postmenopausal Women, Nitrofurantoin, Antibiotic Prophylaxis, Gynoflor, Lactobacillus, Estriol, Vaginal Probiotics, Urinary Microbiome, 16S rRNA Sequencing, qPCR, Lower Urinary Tract Symptoms, RUTISS Questionnaire, Adherence Monitoring, Antimicrobial Resistance, Thailand
- Medical subject headings
- Cystitis, Recurrence, Urinary Tract Infections, Lower Urinary Tract Symptoms
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
NitrofurantoinDrug
Also called Nitrofurantoin macrocrystals/monohydrate
Nightly oral nitrofurantoin 100 mg for 6 months as prophylaxis for recurrent UTI in postmenopausal women. If symptomatic UTI occurs, treat per standard care and, once resolved, continue assigned prophylaxis to complete 6 months. Monitoring per protocol: baseline and month-6 visits with urinalysis, urine culture, urinary microbiome, and kidney function; twice-weekly phone/Line check-ins for adherence, symptoms, and adverse events.
GynoflorDrug
Also called Vaginal Lactobacillus with ultra-low-dose estriol
Vaginal tablet containing Lactobacillus with ultra-low-dose estriol. Insert 1 tablet nightly for 14 days, then twice weekly through month 6 as prophylaxis against recurrent urinary tract infection. If a symptomatic UTI occurs, treat per standard of care; after resolution, continue assigned prophylaxis to complete 6 months. Monitoring identical to comparator.
| Study group | Role | What they receive |
|---|---|---|
| Nitrofurantoin Prophylaxis | Active comparator | Nightly oral nitrofurantoin 100 mg for 6 months as prophylaxis for recurrent UTI in postmenopausal women. If symptomatic UTI occurs, treat per standard care and, once resolved, continue assigned prophylaxis to complete 6 months. Monitoring per protocol: baseline and month-6 visits with urinalysis, urine culture, urinary microbiome, and kidney function; twice-weekly phone/Line check-ins for adherence, symptoms, and adverse events. Receives: Drug: Nitrofurantoin |
| Gynoflor Vaginal Tablet | Experimental | Vaginal tablet containing Lactobacillus with ultra-low-dose estriol (Gynoflor) for 6 months: insert 1 tablet nightly for 14 days, then twice weekly through month 6. Same monitoring and management as comparator: if UTI occurs, treat per standard care and then resume assigned prophylaxis to finish 6 months. Receives: Drug: Gynoflor |
What is being measured
The primary outcome is the main question the study is designed to answer.
Proportion of participants with recurrent UTI within 6 months
Number of participants who experience ≥1 episode of symptomatic urinary tract infection (UTI) during the 6-month prophylaxis period, confirmed by clinical symptoms and positive urine culture per hospital standard. Event counted once per participant; groups compared between arms.
Measured: Baseline to 6 months after randomization
Secondary outcomes (7)
Time to first recurrent UTI
Days from randomization to first symptomatic, culture-confirmed UTI during the 6-month period; participants without an event are censored at 6 months.
Measured: Baseline to 6 months
Antibiotic resistance among breakthrough infections
Proportion of bacterial isolates from breakthrough UTIs that are non-susceptible to commonly tested antibiotics per local microbiology reporting.
Measured: During the 6-month prophylaxis period
Change in lower urinary tract symptom score (RUTISS, Thai)
Change in Recurrent Urinary Tract Infection Symptom Scale (RUTISS) Section C Severity Score
Description: Mean change in the Recurrent Urinary Tract Infection Symptom Scale (RUTISS) Section C total severity score from baseline to Month 6. Section C summarizes four domains (urinary symptoms, urinary presentation, UTI pain/discomfort, bodily sensations). The Overall RUTISS Severity Score is calculated as: sum of Section C responses ÷ 11 × 10, yielding a 0-100 scale. Higher scores = worse symptom/pain severity.
Time Frame: Baseline and Month 6.
Unit of Measure: Points (0-100).
Scale Details: Minimum = 0, Maximum = 100, Higher = worse
Measured: Baseline and month 6
Lactobacillus abundance by qPCR
Change in Lactobacillus copy number/relative abundance in midstream urine measured by quantitative PCR.
Measured: Baseline and month 6
Urinary microbiome diversity by 16S rRNA sequencing
Change in alpha-diversity indices of urine microbiota profiles determined by 16S rRNA gene sequencing.
Measured: Baseline and month 6
Incidence of adverse events related to intervention
Number and proportion of participants with any intervention-related adverse event
Measured: Up to 6 months
Adherence to assigned prophylaxis
Proportion of scheduled doses taken, assessed by medication logs and twice-weekly contacts
Measured: During 6 months
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted22 Sep 2025
- Study start11 Sep 2025
- Primary completion30 Jun 2026 (estimated)
- Study completion30 Aug 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Cystitis, RecurrentStudies of the same condition, open and under way.
- More trials run by Mahidol UniversityThe sponsor's other registered studies.
- 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 4
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Model description
- Randomized, two-arm, parallel-group, open-label trial in postmenopausal women with recurrent UTI. Participants are allocated 1:1 by computer-generated block randomization to: (a) nitrofurantoin 100 mg orally at bedtime for 6 months, or (b) Gynoflor vaginal tablet nightly for 14 days then twice weekly through month 6. Baseline and month-6 clinic visits with labs/microbiome sampling; twice-weekly remote check-ins for adherence, symptoms, and AEs. If symptomatic UTI occurs, treat per standard care and then continue assigned prophylaxis to complete 6 months.
- Masking
- None (open label)
- Enrolment
- 100 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Mahidol University
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07186465
- Sponsor's protocol ID
- MURA2024/339
- Other IDs
- Ref.2024/671
- Acronym
- microbiome
- Status last verified
- Sep 2025
- First submitted
- 15 Sep 2025
- Last updated
- 25 Sep 2025
- Results posted
- No
- Data monitoring committee
- Yes
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified individual participant data (IPD) underlying the primary and secondary outcome results will be shared. A data dictionary and coding key will be provided. Direct identifiers will be removed and dates shifted as needed. Data will be shared for research purposes only and not for commercial use.
Study at a glance
From the registry record, last updated by the sponsor on 25 Sep 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Evaluating Urinary Microbiome Modulation :An RCT of Antibiotic vs Gynoflor Prophylaxis in Postmenopausal Women With Recurrent Cystitis
- ClinicalTrials.gov ID
- NCT07186465
- Acronym / sponsor ID
- microbiome / MURA2024/339
- Conditions
- Cystitis, Recurrent, Urinary Tract Infections
- Keywords
- Postmenopausal Women, Nitrofurantoin, Antibiotic Prophylaxis, Gynoflor, Lactobacillus, Estriol, Vaginal Probiotics, Urinary Microbiome
- Phase
- Phase 4
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 100 participants (estimated)
- Lead sponsor
- Mahidol UniversityUniversity, hospital or other
- Study start
- 11 Sep 2025 (actual)
- Primary completion
- 30 Jun 2026 (estimated)
- Study completion
- 30 Aug 2026 (estimated)
- First posted
- 22 Sep 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This open-label, parallel-group randomized controlled trial compares two prophylaxis strategies for recurrent urinary tract infection (rUTI) in postmenopausal women: (1) nightly oral nitrofurantoin 100 mg for 6 months versus (2) a vaginal tablet containing Lactobacillus with ultra-low-dose estriol (Gynoflor: nightly for 14 days, then twice weekly to month 6). Participants (≥40 years) are randomized 1:1 in computer-generated blocks and followed for 6 months. The primary endpoint is the proportion with rUTI recurrence within 6 months. Secondary endpoints include time to first recurrence, antibiotic resistance in breakthrough infections, change in lower urinary tract symptoms (Thai RUTISS), and urinary microbiome measures (Lactobacillus dominance and community diversity by qPCR and 16S rRNA). Key assessments occur at baseline and month 6 (urinalysis, culture, urinary microbiome sampling, and kidney function). Adherence and adverse events are captured via twice-weekly phone/Line contacts. Approximately 100 participants (50 per arm) will be enrolled as a feasibility-sized pilot.
Detailed description
Background and Rationale
Recurrent cystitis is common after menopause and burdens quality of life and healthcare use. Antibiotic prophylaxis is effective but may promote antimicrobial resistance with long-term use. Vaginal Lactobacillus with ultra-low-dose estriol can restore urogenital flora and potentially reduce rUTI and lower urinary tract symptoms. Comparative data versus nightly antibiotic prophylaxis-and effects on the urinary microbiome-remain limited. This trial directly evaluates clinical recurrence and microbiome modulation with nitrofurantoin versus a Lactobacillus/estriol vaginal tablet over 6 months.
Objectives
Primary objective: Compare the 6-month rUTI recurrence proportion between nitrofurantoin and Gynoflor.
Key secondary objectives: (a) time to first recurrence; (b) antimicrobial resistance patterns in breakthrough infections; (c) change in Thai RUTISS score; (d) Lactobacillus dominance and within-sample diversity of the urinary microbiome.
Key Endpoint Definitions
rUTI recurrence (primary): ≥1 symptomatic episode meeting clinical criteria with urine culture growth of a uropathogen during the 6-month follow-up (episodes during temporary treatment holds still count toward the endpoint).
Time to first recurrence: days from randomization to first qualifying rUTI.
Antibiotic resistance: susceptibility profile of cultured uropathogens from breakthrough infections, categorized per local laboratory standards.
Microbiome metrics: quantitative Lactobacillus abundance (qPCR) and alpha diversity indices from 16S rRNA profiling.
Design Overview
Open-label, two-arm, parallel RCT with 1:1 allocation by concealed, computer-generated block randomization. Follow-up is 6 months. Masking is not feasible due to intervention routes; laboratory personnel for microbiome and culture testing are shielded from allocation where practicable.
Interventions (Summary)
Nitrofurantoin arm: 100 mg orally once nightly through month 6.
Gynoflor arm: one vaginal tablet nightly for 14 days, then twice weekly (e.g., Monday/Friday) through month 6.
(Rescue treatment for symptomatic UTI follows standard of care; study prophylaxis resumes afterward to complete 6 months.)
Study Procedures (Selected)
Baseline (Day 0): consent, randomization, Thai RUTISS, urinalysis, urine culture, urinary microbiome sampling, BUN/creatinine.
Follow-up (Months 0-6): twice-weekly phone/Line check-ins to reinforce adherence and capture symptoms/adverse events; prompt clinical evaluation if UTI symptoms arise.
Month 6: repeat Thai RUTISS, urinalysis/culture, urinary microbiome sampling, BUN/creatinine.
Specimen handling: midstream clean-catch urine; UA ~20 mL, culture 5-10 mL, microbiome ~50 mL. Samples processed promptly or refrigerated at 4 °C ≤24 h if needed.
Laboratory Methods (Overview)
Urinary microbiome assays are performed at the Department of Medical Sciences: (1) qPCR estimating Lactobacillus abundance across time points; (2) 16S rRNA gene sequencing for community profiling and alpha diversity.
Sample Size and Analysis Plan (Pilot)
Approximately 100 participants (50/arm) are planned based on local feasibility for an initial pilot. Analyses will follow intention-to-treat with supportive per-protocol summaries. The primary endpoint will be compared between arms using a risk difference with 95% CIs and a chi-square or Fisher's exact test. Time-to-event data will be presented with Kaplan-Meier estimates and log-rank testing. Continuous outcomes (e.g., Thai RUTISS change) will use t-tests or Wilcoxon rank-sum as appropriate; paired pre/post within-arm changes will use paired tests. Missing outcome data will be handled by complete-case analysis with sensitivity analyses (e.g., worst-case imputation for the primary endpoint) if missingness >5-10%.
Safety Monitoring and Adherence
Expected risks include nitrofurantoin intolerance (e.g., GI upset, hypersensitivity), local vaginal irritation, minor phlebotomy discomfort, and time burden. Adverse events are solicited during twice-weekly contacts and at visits; serious adverse events are reported per IRB policy. Given the low-risk profile and pilot scope, a formal DSMB is not planned; the PI and study team review safety at regular intervals. Adherence is promoted by structured reminders and documented via participant report during check-ins.
Data Management and Quality
Case report forms are source-verified against electronic medical records and laboratory outputs. Microbiome and culture laboratories follow internal QC procedures; analytical staff are kept unaware of allocation when feasible. Randomization files are access-restricted; analysis is pre-specified prior to database lock.
Study design
- Primary purpose
- Prevention
- Allocation
- Randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 2
- Model description
- Randomized, two-arm, parallel-group, open-label trial in postmenopausal women with recurrent UTI. Participants are allocated 1:1 by computer-generated block randomization to: (a) nitrofurantoin 100 mg orally at bedtime for 6 months, or (b) Gynoflor vaginal tablet nightly for 14 days then twice weekly through month 6. Baseline and month-6 clinic visits with labs/microbiome sampling; twice-weekly remote check-ins for adherence, symptoms, and AEs. If symptomatic UTI occurs, treat per standard care and then continue assigned prophylaxis to complete 6 months.
| Arm | Type | Receives |
|---|---|---|
| Nitrofurantoin Prophylaxis | Active comparator | Drug: NitrofurantoinNightly oral nitrofurantoin 100 mg for 6 months as prophylaxis for recurrent UTI in postmenopausal women. If symptomatic UTI occurs, treat per standard care and, once resolved, continue assigned prophylaxis to complete 6 months. Monitoring per protocol: baseline and month-6 visits with urinalysis, urine culture, urinary microbiome, and kidney function; twice-weekly phone/Line check-ins for adherence, symptoms, and adverse events. |
| Gynoflor Vaginal Tablet | Experimental | Drug: GynoflorVaginal tablet containing Lactobacillus with ultra-low-dose estriol (Gynoflor) for 6 months: insert 1 tablet nightly for 14 days, then twice weekly through month 6. Same monitoring and management as comparator: if UTI occurs, treat per standard care and then resume assigned prophylaxis to finish 6 months. |
Who may qualify
- Ages
- 40 years and older
- Sex
- Female only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (6 listed)
- Female, postmenopausal, age ≥40 years
- Clinical history of recurrent urinary tract infection (rUTI) as assessed by the investigator
- Able and willing to take assigned prophylaxis for 6 months
- Able to attend baseline and Month 6 study visits and provide urine samples
- Able to provide written informed consent
Key exclusion criteria (8 listed)
- Current symptomatic UTI at enrollment (may be treated and reconsidered after resolution)
- Known hypersensitivity or contraindication to nitrofurantoin or to the Lactobacillus/estriol vaginal tablet (Gynoflor) or their excipients; significant renal impairment or other label-based contraindications to nitrofurantoin per local practice
- Planned urologic surgery or procedure expected during the 6-month study period
- Recent bacterial vaginosis (e.g., within the past month) or active vulvovaginal skin disorders precluding vaginal product use
- History of hormone-dependent malignancy (e.g., breast, uterine, or cervical cancer) or unexplained abnormal vaginal bleeding
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| NitrofurantoinAlso: Nitrofurantoin macrocrystals/monohydrateNightly oral nitrofurantoin 100 mg for 6 months as prophylaxis for recurrent UTI in postmenopausal women. If symptomatic UTI occurs, treat per standard care and, once resolved, continue assigned prophylaxis to complete 6 months. Monitoring per protocol: baseline and month-6 visits with urinalysis, urine culture, urinary microbiome, and kidney function; twice-weekly phone/Line check-ins for adherence, symptoms, and adverse events. | Drug | Nitrofurantoin Prophylaxis |
| GynoflorAlso: Vaginal Lactobacillus with ultra-low-dose estriolVaginal tablet containing Lactobacillus with ultra-low-dose estriol. Insert 1 tablet nightly for 14 days, then twice weekly through month 6 as prophylaxis against recurrent urinary tract infection. If a symptomatic UTI occurs, treat per standard of care; after resolution, continue assigned prophylaxis to complete 6 months. Monitoring identical to comparator. | Drug | Gynoflor Vaginal Tablet |
Primary outcome
Proportion of participants with recurrent UTI within 6 months
Time frame: Baseline to 6 months after randomization
Number of participants who experience ≥1 episode of symptomatic urinary tract infection (UTI) during the 6-month prophylaxis period, confirmed by clinical symptoms and positive urine culture per hospital standard. Event counted once per participant; groups compared between arms.
7 secondary outcomes
Time to first recurrent UTI
Time frame: Baseline to 6 months
Antibiotic resistance among breakthrough infections
Time frame: During the 6-month prophylaxis period
Change in lower urinary tract symptom score (RUTISS, Thai)
Time frame: Baseline and month 6
Lactobacillus abundance by qPCR
Time frame: Baseline and month 6
Urinary microbiome diversity by 16S rRNA sequencing
Time frame: Baseline and month 6
Incidence of adverse events related to intervention
Time frame: Up to 6 months
Adherence to assigned prophylaxis
Time frame: During 6 months
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 25 Sep 2025.
- Individual participant dataSharing planned: Yes. De-identified individual participant data (IPD) underlying the primary and secondary outcome results will be shared. A data dictionary and coding key will be provided. Direct identifiers will be removed and dates shifted as needed. Data will be shared for research purposes only and not for commercial use.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 4 study testing Nitrofurantoin and Gynoflor in people with Cystitis, Recurrent and Urinary Tract Infections, run by Mahidol University at 1 site in Thailand.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 6 inclusion and 8 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 25 Sep 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Thailand. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 4 studies take place after a treatment is approved, to learn more about its long-term benefits and risks in everyday use.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Lappanawat Santitham (+66944314994, cambellabios@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Proportion of participants with recurrent UTI within 6 months (time frame: Baseline to 6 months after randomization). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 25 Sep 2025.