Microbiome-Modulating Prophylaxis RCT: Antibiotic vs Gynoflor in Postmenopausal Women With Recurrent Cystitis

Trial statusRecruiting
Trial phasePhase 4
Trial typeInterventional
Biological sexFemale
Age40+
SponsorMahidol University

About this trial

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.

Eligibility criteria

Qualifiers

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

Disqualifiers

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

Trial design

Treatments tested in this trial

  • Nitrofurantoin
  • Gynoflor

Treatment groups

100 Participants
are divided into 2 treatment groups

Sponsors and collaborators