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Study on Early Oxybutynin Treatment for Boys with Posterior Urethral Valves

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What is this trial about?

A plain-language summary of the goals, design and what participants do

This clinical trial is focused on studying a condition known as posterior urethral valves, which affects the urinary tract in boys. The trial is investigating the effects of a treatment using a medication called oxybutynin, which is administered in the form of a syrup. Oxybutynin is known for its properties as an anticholinergic and antispasmodic, meaning it helps to relax the bladder muscles and reduce spasms.

The purpose of the study is to understand how early treatment with oxybutynin can influence bladder function in boys who have undergone surgery to remove the posterior urethral valves. The study will observe changes in bladder compliance, which refers to how well the bladder can stretch and hold urine, as well as bladder volume and the pressure during urination. Boys participating in the study will receive the treatment for a period of up to nine months.

Throughout the study, researchers will monitor various aspects of the boys' health, including any side effects from the treatment and the occurrence of urinary tract infections. The study will also involve regular check-ups to assess the condition of the kidneys using ultrasound, a method that uses sound waves to create images of the inside of the body. Additionally, the study will look at how the body processes oxybutynin by measuring its levels in the blood at different times. This will help to understand how the medication is absorbed and broken down in the body. The study aims to provide valuable insights into the management of posterior urethral valves in young boys.

The research process

The trial runs in 6 steps – from screening to follow-up. Each step says what happens and what the team monitors.

  1. Step 1

    Joining the study

    Participation begins after signing a free, informed, and written consent form. This must be completed before any study-related examinations.

  2. Step 2

    Initial assessment

    An initial assessment is conducted to confirm eligibility. This includes reviewing the diagnosis of posterior urethral valves and ensuring that valve resection was performed within the first 3 months of life.

    Urodynamic studies are reviewed to check for abnormal bladder function, such as high voiding pressure or small bladder capacity.

  3. Step 3

    Treatment administration

    The treatment involves the administration of oxybutynin in syrup form, taken buccally. The specific dosage and frequency are determined by the study protocol and the medical team.

  4. Step 4

    Monitoring and follow-up

    Regular follow-up visits are scheduled to monitor bladder function and overall health. These visits include assessments of bladder compliance, voiding pressure, and bladder volume.

    Pharmacokinetic samples are collected at 2 weeks, 3 months, and 9 months after starting treatment to study the body's processing of oxybutynin.

  5. Step 5

    Evaluation of treatment success

    The primary goal is to achieve improved bladder function by 9 months after starting treatment. Success is defined by specific improvements in bladder compliance, voiding pressure, and bladder volume.

  6. Step 6

    Final assessment

    A final assessment is conducted to evaluate the overall outcomes of the treatment, including any adverse events, urinary tract infections, and changes in kidney function.

Who can join the trial?

5 criteria

  • The participant must be a boy aged between 3 to 6 months.
  • The participant must have been diagnosed with **posterior urethral valves**, which are blockages in the tube that carries urine out of the bladder, and must have had a procedure to remove these blockages within the first 3 months of life.
  • The participant must have undergone **urodynamic studies**, which are tests to see how well the bladder and urethra are storing and releasing urine, between 10 weeks and 6 months of age. These tests should show abnormal results, such as high pressure when urinating (more than 60 cm H2O), a small bladder capacity (less than 70% of the expected size), and for those without certain natural pressure reliefs, poor bladder flexibility (less than 10 ml/cm H2O).
  • The participant must be affiliated with or a beneficiary of a social security scheme.
  • Free, informed, and written consent must be signed by the participant and the investigator before any examination required by the research, at the latest on the day of inclusion.

Who cannot join the trial?

4 criteria

  • Only boys can participate, so girls are excluded.
  • Participants must be within a specific age range, so those outside this range cannot join.
  • Individuals with conditions other than the specified **urethral posterior valve** are not eligible.
  • Participants must not belong to a vulnerable population, which means they should not be in a situation that makes them more at risk or in need of special protection.
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Investigated drugs

Oxybutynin is a medication used in this trial to help improve bladder function in boys who have had surgery for posterior urethral valves. It works by relaxing the bladder muscles, which can help increase bladder capacity and reduce the pressure during urination. The goal of using oxybutynin in this study is to see if it can positively affect bladder function after the surgical procedure.

What is already known about the treatment

Oxybutynin – Oxybutynin is typically administered orally in tablet form or as a transdermal patch. It is currently being studied in clinical trials for its effects on bladder function in boys with posterior urethral valves. The main therapeutic indication for oxybutynin is to manage symptoms of overactive bladder, such as frequent urination and urgency. At the molecular level, oxybutynin works by blocking muscarinic receptors, which reduces bladder muscle contractions. It is classified pharmacologically as an anticholinergic agent.

Investigated diseases

Posterior Urethral Valve – This condition is a congenital obstruction in the male urethra, specifically located at the posterior part, which can impede the normal flow of urine. It is caused by abnormal folds of tissue that form a blockage, leading to difficulty in urination. Over time, this obstruction can cause the bladder to work harder, potentially leading to bladder dysfunction. The increased pressure can also affect the kidneys, possibly resulting in kidney damage if not addressed. Symptoms may include a weak urinary stream, urinary tract infections, and difficulty in urination. Early detection and management are crucial to prevent complications related to the urinary system.
Trial detailsLast updated 2 Oct 2026
Age0-17PhasePhase IITrial ID2024-515844-22-00Protocol codeCHUBX 2018/65Estimated enrolment50 patientsSponsorCentre Hospitalier Universitaire De Bordeaux

sourced from the EU Clinical Trials Register and site verification

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On this site, “treatment” means an investigational medicine being studied in a clinical trial. Its safety and efficacy for the use being studied have not yet been confirmed, some participants may receive a placebo or a comparator medicine, and taking part does not guarantee any health benefit. The decision to take part is made by the doctor at the research site. This site is for information only and does not replace medical advice.

This service is not affiliated with the European Commission, the EMA, or the official CTIS system. Most information comes from publicly available international clinical-trial registries, supplemented by data from academic sites, national regulators and commercial sponsors. On this site, “treatment” and “therapy” mean a medicine being tested in a clinical trial. Its safety and effectiveness in the use being studied are not yet confirmed, some participants may receive a placebo or a comparator, and taking part does not guarantee a health benefit. The doctor at the research site decides who can take part. This site provides information, not medical advice. Certain content and visual elements on this website have been generated or enhanced using artificial intelligence (AI).