Efficacy and Mechanism of Action of Methenamine Hippurate (Hiprex™) in Women With Recurring Urinary Tract Infections.

NCT04709601 | Terminated Phase 4 Results DMC FDA Drug

• 1 other identifier: STU-2020-0725
• Study Type: interventional
• Target: 14
• Locations: 1 country
• Sites: 1

Brief Summary

The purpose of this study is to measure the concentration of formaldehyde in the urine of women with recurrent urinary tract infections on Hiprex; and then, assuming its urinary presence is confirmed at the proper acid urinary pH, evaluate if such a therapy has favorable effects in decreasing the rate of recurrent urinary tract infections over time.

Conditions

Urinary Tract Infections

Outcome Measures

Primary Outcomes (1)

• Number of Urinary Tract Infections

  It would be measured by counting the positive urine cultures, or UTI-like episodes requiring antibiotic treatment during the 1 year of the study period.

  1 year

Secondary Outcomes (9)

• Frequency of Oral Antibiotic Use

  1 year

• Number of Participants That Used Oral Anti-biotic

  1 year

• Number of Hospital Re-admissions at 1 Year

  1 year

• Frequency and Severity of Adverse Events Related to Hiprex

  1 year

• Urine Acidity Levels

  1 year

Study Arms (1)

Group 1 - Patients with negative and positive urine culture

EXPERIMENTAL

Drug: Hiprex

Interventions

Hiprex DRUG

Patients with negative urine culture will be prescribed Hiprex 1 g PO BID x 1 yr and patients with a positive urine culture will be prescribed antibiotics.

Also known as: Methenanime hippurate

Group 1 - Patients with negative and positive urine culture

Eligibility Criteria

• Age: 50 Years - 85 Years
• Sex: female
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Female
• Age 50 - 85
• Have RUTIs (at least 2 UTIs within the past 6 months or 3 within the past year) -

You may not qualify if:

• Being on antibiotics at baseline (i.e. suppressive therapy or antibiotic therapy for urinary or non-urinary infections)
• Neurogenic bladder condition
• Using urinary catheters (including Foley catheter, intermittent catheterization, and suprapubic catheter)
• Uncontrolled diabetes (HbA1c \> 9)
• Chronic renal failure defined as serum creatinine \> 1.5 mg/dL
• History of liver disease
• Patients from out of town, in whom follow-up will not be possible
• Pregnancy
• Allergy to Hiprex
• Inability to take Hiprex reliably at home, such as having psychosis, dementia, or swallowing disorders
• Non-English speakers -

Sponsors & Collaborators

• University of Texas Southwestern Medical Center: lead

Study Sites (1)

UT-Southwestern Medical Center

Dallas, Texas, 75390, United States

Location

MeSH Terms

Conditions

Urinary Tract Infections

Interventions

methenamine hippurate

Condition Hierarchy (Ancestors)

Infections; Urologic Diseases; Female Urogenital Diseases; Female Urogenital Diseases and Pregnancy Complications; Urogenital Diseases; Male Urogenital Diseases

Results Point of Contact

• Title: Dr. Philippe Zimmern, M.D.
• Organization: University of Texas Southwestern Medical Center

philippe.zimmern@utsouthwestern.edu

214-645-8765

Study Officials

• Philippe Zimmern, MD

  University of Texas Southwestern Medical Center

  PRINCIPAL INVESTIGATOR

Publication Agreements

• PI is Sponsor Employee: Yes

Study Design

• Study Type: interventional
• Phase: phase 4
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: Professor of Urology

Study Record Dates

• First Submitted: December 17, 2020
• First Posted: January 14, 2021
• Study Start: January 4, 2021
• Primary Completion: December 31, 2024
• Study Completion: December 31, 2024
• Last Updated: February 24, 2026
• Results First Posted: February 24, 2026

Record last verified: 2026-02

Data Sharing

• IPD Sharing: Will not share

Locations

US (1)