Spinal Cord InjuriesPhase 2NCT04565925
Sildenafil for Treatment of Urinary Incontinence in Patients With Spinal Cord Injuries
A Phase 2 study testing Sildenafil Citrate in people with Spinal Cord Injuries and Urinary Incontinence, run by The University of Texas Medical Branch, Galveston at 2 sites in United States.
Trial summary
The goal of this study is to determine whether administration of sildenafil will decrease urine leakage in patients with spinal cord injuries. Read more about this study
- Who is it for?
- Ages 18 to 70 years
- Conditions the study is for
- Spinal Cord Injuries, Urinary Incontinence
- What is being tested?
- Sildenafil Citrate
- Could I receive a placebo?
- Yes, some participants may receive a placebo
- How many people
- 24 participants
- Where
- 2 sitesUnited States
- Study dates
- 7 Jul 2021to 1 Dec 2026
- Phase
- Phase 2
- 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 18 to 70 years
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Adults with spinal cord injury (SCI), 18-75 years of age, at the time of consent
- Have urinary incontinence (UI), with at least 3 leakage episodes/week
- Have urodynamics assessment on file with their provider in past 3 years. If no historical data on file, subject may complete prior to study visit 1.
- Willing and able to comply with study procedures
- Willing and able to provide written informed consent
Who cannot join
- In phone prescreen, delighted or pleased with current quality of life due to urinary symptoms.
- Indwelling catheter
- History of greater than 4 urinary tract infections per year
- Multiple sclerosis
- Significant heart, liver, kidney, pulmonary, blood, autoimmune or peripheral vascular disease
- Systolic blood pressure <90 or >170, diastolic blood pressure <50 or >110 after repeated evaluation with proper cuff. This range is the acceptable range stated in the prescribing information for sildenafil (>90/50 and <170/110)
Show all 15Show fewer
- Active cancer
- HIV, Hepatitis B, or Hepatitis C
- Use of systemic nitrates, anabolic steroids, corticosteroids, or long acting PDE5 inhibitors in the past 1 month
- Use of short acting PDE5 inhibitors in the past 1 week
- Use of alpha blockers, anticholinergic agents, bethanechol, or other UI treatment within the past 2 weeks ( 3 weeks for long acting muscarinic receptor antagonists)
- Known allergic reaction to any agent under investigation or required by the protocol
- Females who are pregnant or lactating
- Atonic bladder or high detrusor and high pelvic floor muscle pressure based on previous cystometrogram (CMG) (on file with their provider) that would place subjects at risk for kidney injury
- Any medical condition that, in the opinion of the investigator, would place the subject at increased risk for participation
Trial locations and contacts
2 sites in 1 country.
United States2 sites
Texas A&M University
College Station, Texas, 77843
University of Texas Medical Branch
Galveston, Texas, 77555
About this study
The goal of this study is to determine whether administration of sildenafil will decrease urine leakage in patients with spinal cord injuries.
Read the detailed description
Spinal cord injury (SCI) is a devastating condition affecting 291,000 women and men in the US alone. Urinary incontinence (UI) is a common problem in these patients, affecting 52% of the population, with episodes of incontinence occurring daily in 20-27% of affected persons. UI after spinal cord injury (SCI) is a major cause of distress and morbidity amongst patients with SCI, and is associated with decreased quality of life in general, physical, and emotional domains. UI has the undesirable side effects of perineal irritation and infection, increased odor, disrupted sleep, embarrassment, need to change clothes/bedding, and sexual dysfunction, as well as significant financial burden. Persons living with a SCI have ranked urinary problems as the most important health problem after injury. Addressing this significant problem and providing relief has the potential to significantly improve the lives of patients with SCI.
Typical treatment options are geared toward the type of UI in each patient. For stress UI, the goal of treatment is to provide support to the pelvic floor and urethra. Pessaries (devices placed inside the vagina in women) or surgery (e.g. suburethral sling) to elevate the urethra and/or bladder neck to increase the resistance to leak through the urethra are commonly used. Urethral bulking agents or pelvic muscle floor therapy are also employed to strengthen the closure pressure of the urethra in patients with stress UI. No pharmacologic agents are currently available to treat stress UI. For urge UI, medications or electrical stimulation aimed at relaxation of the detrusor muscle, including anticholinergics, are used. For overflow or obstructive UI, treatments are aimed at shrinking or removing the obstruction, such as medications to shrink the prostate, prostatectomy or mass removal. For neurogenic UI, surgery for diversion or implant placement may be utilized.
Sildenafil (Viagra) has been well studied and used extensively in males to treat erectile dysfunction. Phosphodiesterase 5 (PDE5) inhibitors, including sildenafil, are potent vasodilators that enhance tissue perfusion, relax smooth muscle of the vasculature and bladder, and stimulate skeletal muscle protein synthesis. It has been reported to improve lower urinary tract symptoms, including urge UI and benign prostatic hyperplasia (BPH) in men. In our team's recent study using sildenafil for treatment of UI in women, the investigators found improvement in quality of life and a decrease in the number of incontinence episodes in women taking sildenafil. Higher sildenafil plasma levels were associated with greater improvement in symptoms. While the types of UI in women are somewhat different than in men, studies have shown improvements in UI in both sexes.
Thus, the investigators propose to conduct a two month randomized, placebo-controlled crossover trial of sildenafil in male and female adult SCI patients with UI to assess the therapeutic potential of sildenafil to reduce the symptoms of urinary leakage.
Aims:
Aim 1: To determine whether sildenafil will decrease episodes of leakage of UI in adult women and men with SCI.
Aim 2: To determine the effects of sildenafil on the subjective measures of UI, including quality of life.
Experimental Protocol:
Investigators will study patients with spinal cord injuries (aged 18-70) with current urine leakage of more than 3 times/week (n=24). Subjects will undergo a double blinded randomized cross over treatment of sildenafil (20mg TID) and placebo. Each treatment period will last 4 weeks with a 2 week washout between treatment periods.
Before and after each treatment period, subjects will undergo testing which will consist of measurements of urine post void residual volume (PVR), adverse event assessment, and questionnaires of quality of life and urinary health.
- Conditions
- Spinal Cord Injuries, Urinary Incontinence
- Being tested
- Sildenafil Citrate, Placebo
- Medical subject headings
- Spinal Cord Injuries, Urinary Incontinence
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Sildenafil CitrateDrug
Also called Revatio
Sildenafil 20mg TID for 4 weeks
PlaceboDrug
Also called Lactose
Placebo (Lactose) TID for 4 weeks
| Study group | Role | What they receive |
|---|---|---|
| Sildenafil 20mg TID then Placebo TID | Experimental | Subjects will be administered Sildenafil 20mg TID for 4 weeks. There will be a 2 week washout period then subjects will be administered Placebo (lactose) TID for 4 weeks. Receives: Drug: Sildenafil Citrate; Drug: Placebo |
| Placebo TID then Sildenafil 20mg TID | Experimental | Subjects will be administered Placebo (lactose) TID for 4 week. There will be a 2 week washout period and then subjects will be administered Sildenafil 20mg TID for 4 weeks. Receives: Drug: Sildenafil Citrate; Drug: Placebo |
What is being measured
The primary outcome is the main question the study is designed to answer.
Bladder Leakage as measured by 5 day bladder diary at Baseline
Bladder leakage will be measured by bladder diary, which will be kept for five- 24 hours periods at baseline. Subjects will be asked to record the number of leaks each day. Data will be calculated by summing total number of leaks over the 5 day recording period and dividing the sum by 5, resulting in average leaks per day.
Measured: baseline
Bladder Leakage as measured by 5 day bladder diary after 4 weeks of Sildenafil Treatment
Bladder leakage will be measured by bladder diary, which will be kept for five 24 hours periods in the last week of the 4 weeks of sildenafil treatment.
Measured: after 4 weeks of sildenafil treatment
Bladder Leakage as measured by 5 day bladder diary after 4 weeks of Placebo Treatment
Bladder leakage will be measured by bladder diary, which will be kept for five 24 hours periods in the last week of the 4 weeks of placebo treatment.
Measured: after 4 weeks of placebo treatment
Secondary outcomes (18)
Blood sildenafil levels as measured by Liquid Chromatography Mass Spectrometry (LCMS) at baseline
Sildenafil levels will be measured in plasma samples taken at baseline using a Liquid Chromatography Mass Spectrometry-Mass Spectrometry (LCMS-MS) method. Data will be reported as ng/ml.
Measured: baseline
Blood sildenafil levels as measured by Liquid Chromatography Mass Spectrometry (LCMS) after 4 weeks of sildenafil treatment
Sildenafil levels will be measured in plasma samples taken after 4 weeks of sildenafil treatment using a Liquid Chromatography Mass Spectrometry-Mass Spectrometry (LCMS-MS) method. Data will be reported as ng/ml.
Measured: after 4 weeks of sildenafil treatment
Blood sildenafil levels as measured by Liquid Chromatography Mass Spectrometry (LCMS) after 4 weeks of placebo treatment
Sildenafil levels will be measured in plasma samples taken after 4 weeks of placebo treatment using a Liquid Chromatography Mass Spectrometry-Mass Spectrometry (LCMS-MS) method. Data will be reported as ng/ml.
Measured: after 4 weeks of placebo treatment
Post void residual urine volume as measured by ultrasound bladder scanner at baseline
Post void residual urine volume is measured using an ultrasound bladder scanner. To perform this test, the research subject empties their bladder and then the bladder scanner is used to measure any remaining urine in the bladder. Results will be reported as mL urine remaining.
Measured: baseline
Post void residual urine volume as measured by ultrasound bladder scanner after 4 weeks of sildenafil treatment
Post void residual urine volume is measured using an ultrasound bladder scanner. To perform this test, the research subject empties their bladder and then the bladder scanner is used to measure any remaining urine in the bladder. Results will be reported as mL urine remaining.
Measured: after 4 weeks of sildenafil treatment
Post void residual urine volume as measured by ultrasound bladder scanner after 4 weeks of placebo treatment
Post void residual urine volume is measured using an ultrasound bladder scanner. To perform this test, the research subject empties their bladder and then the bladder scanner is used to measure any remaining urine in the bladder. Results will be reported as mL urine remaining.
Measured: after 4 weeks of placebo treatment
Urinary symptoms as measured by the American Urological Association Symptom Score at baseline
Urinary symptoms will be assessed using the American Urological Association (AUA) Symptom Score, a 7 item questionnaire that assess how bothersome urinary problems are and if treatment is effective. The AUA symptom score yields one overall score (range 0 - 35, with higher scores indicating higher severity). Total scores of 0-7 mild symptoms; 8-19 moderate symptoms; 20-35 severe symptoms
Measured: baseline
Urinary symptoms as measured by the American Urological Association Symptom Score after 4 weeks of sildenafil treatment
Urinary symptoms will be assessed using the American Urological Association (AUA) Symptom Score, a 7 item questionnaire that assess how bothersome urinary problems are and if treatment is effective. The AUA symptom score yields one overall score (range 0 - 35, with higher scores indicating higher severity). Total scores of 0-7 mild symptoms; 8-19 moderate symptoms; 20-35 severe symptoms
Measured: after 4 weeks of sildenafil treatment
Urinary symptoms as measured by the American Urological Association Symptom Score after 4 weeks of placebo treatment
Urinary symptoms will be assessed using the American Urological Association (AUA) Symptom Score, a 7 item questionnaire that assess how bothersome urinary problems are and if treatment is effective. The AUA symptom score yields one overall score (range 0 - 35, with higher scores indicating higher severity). Total scores of 0-7 mild symptoms; 8-19 moderate symptoms; 20-35 severe symptoms
Measured: after 4 weeks of placebo treatment
Bladder dysfunction as measured by the Neurogenic Bladder Symptom Score at baseline
The Neurogenic Bladder Symptom Score (NBSS) is a validated questionnaire that assess symptoms of bladder dysfunction due to spinal cord injury. Three distinct domains are assessed: incontinence; storage and voiding; and consequences. Scores can range from 0 (no symptoms at all) to 74 (maximum symptoms).
Measured: baseline
Bladder dysfunction as measured by the Neurogenic Bladder Symptom Score after 4 weeks of sildenafil treatment
The Neurogenic Bladder Symptom Score (NBSS) is a validated questionnaire that assess symptoms of bladder dysfunction due to spinal cord injury. Three distinct domains are assessed: incontinence; storage and voiding; and consequences. Scores can range from 0 (no symptoms at all) to 74 (maximum symptoms).
Measured: after 4 weeks of sildenafil treatment
Bladder dysfunction as measured by the Neurogenic Bladder Symptom Score after 4 weeks of placebo treatment
The Neurogenic Bladder Symptom Score (NBSS) is a validated questionnaire that assess symptoms of bladder dysfunction due to spinal cord injury. Three distinct domains are assessed: incontinence; storage and voiding; and consequences. Scores can range from 0 (no symptoms at all) to 74 (maximum symptoms).
Measured: after 4 weeks of placebo treatment
Perception of bladder conditions as measured by the Patient Perception of Bladder Symptoms questionnaire at baseline
The Patient Perceived Bladder Condition (PPBC) is a one item assessment measuring the severity of bladder problems with a likert scale with a range from 1 (best) to 6 (worst).
Measured: baseline
Perception of bladder conditions as measured by the Patient Perception of Bladder Symptoms questionnaire after 4 weeks of sildenafil treatment
The Patient Perceived Bladder Condition (PPBC) is a one item assessment measuring the severity of bladder problems with a likert scale with a range from 1 (best) to 6 (worst).
Measured: after 4 weeks of sildenafil treatment
Perception of bladder conditions as measured by the Patient Perception of Bladder Symptoms questionnaire after 4 weeks of placebo treatment
The Patient Perceived Bladder Condition (PPBC) is a one item assessment measuring the severity of bladder problems with a likert scale with a range from 1 (best) to 6 (worst).
Measured: after 4 weeks of placebo treatment
Urinary Symptoms Interference as measured by Pelvic Floor Impact Questionnaire at baseline
Pelvic Floor Impact Questionnaire (PFIQ-7) is a 7 item questionnaire measuring how much urinary symptoms affect activities of daily living, relationships and feelings. Each question is answered three times each, corresponding to the three scales - bladder/urine; bowel/rectum; vagina/penis). Responses for each question range from "not at all" (0) to "quite a bit" (3). Each scale is scored separately by calculating the mean of all seven questions and multiplying that number by 100 and then dividing by 3. Scale scores range from 0-100 with lower scores indicating less effect on quality of life. PFIQ-7 summary score is calculated by summing all three subscale scores (range 0-300).
Measured: baseline
Urinary Symptoms Interference as measured by Pelvic Floor Impact Questionnaire after 4 weeks of sildenafil treatment
Pelvic Floor Impact Questionnaire (PFIQ-7) is a 7 item questionnaire measuring how much urinary symptoms affect activities of daily living, relationships and feelings. Each question is answered three times each, corresponding to the three scales - bladder/urine; bowel/rectum; vagina/penis). Responses for each question range from "not at all" (0) to "quite a bit" (3). Each scale is scored separately by calculating the mean of all seven questions and multiplying that number by 100 and then dividing by 3. Scale scores range from 0-100 with lower scores indicating less effect on quality of life. PFIQ-7 summary score is calculated by summing all three subscale scores (range 0-300).
Measured: after 4 weeks of sildenafil treatment
Urinary Symptoms Interference as measured by Pelvic Floor Impact Questionnaire after 4 weeks of placebo treatment
Pelvic Floor Impact Questionnaire (PFIQ-7) is a 7 item questionnaire measuring how much urinary symptoms affect activities of daily living, relationships and feelings. Each question is answered three times each, corresponding to the three scales - bladder/urine; bowel/rectum; vagina/penis). Responses for each question range from "not at all" (0) to "quite a bit" (3). Each scale is scored separately by calculating the mean of all seven questions and multiplying that number by 100 and then dividing by 3. Scale scores range from 0-100 with lower scores indicating less effect on quality of life. PFIQ-7 summary score is calculated by summing all three subscale scores (range 0-300).
Measured: after 4 weeks of placebo treatment
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted25 Sep 2020
- Study start7 Jul 2021
- Primary completion1 Dec 2026 (estimated)
- Study completion1 Dec 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Spinal Cord InjuriesStudies of the same condition, open and under way.
- More trials run by The University of Texas Medical Branch, GalvestonThe 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 2
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Model description
- Each subject will be administered both sildenafil 20mg TID for 4 weeks and placebo (lactose) TID for 4 weeks in a crossover fashion with a 2 week washout period between treatments.
- Masking
- Triple blind
- Who is masked
- Participant, Investigator, Outcomes assessor
- Enrolment
- 24 participants (estimated)
Sponsor and investigators
- Sponsor type
- University, hospital or other
- Responsible party
- Sponsor
- Investigators
- Kathy Vincent, MD, Principal investigator, University of Texas
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT04565925
- Sponsor's protocol ID
- 20-0197
- Status last verified
- Sep 2026
- First submitted
- 21 Sep 2020
- Last updated
- 9 Sep 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- Yes
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 9 Sep 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Sildenafil for Treatment of Urinary Incontinence in Patients With Spinal Cord Injuries
- ClinicalTrials.gov ID
- NCT04565925
- Acronym / sponsor ID
- 20-0197
- Conditions
- Spinal Cord Injuries, Urinary Incontinence
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Active, not recruiting
- Enrolment
- 24 participants (estimated)
- Lead sponsor
- The University of Texas Medical Branch, GalvestonUniversity, hospital or other
- Study start
- 7 Jul 2021 (actual)
- Primary completion
- 1 Dec 2026 (estimated)
- Study completion
- 1 Dec 2026 (estimated)
- First posted
- 25 Sep 2020 (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.
The goal of this study is to determine whether administration of sildenafil will decrease urine leakage in patients with spinal cord injuries.
Detailed description
Spinal cord injury (SCI) is a devastating condition affecting 291,000 women and men in the US alone. Urinary incontinence (UI) is a common problem in these patients, affecting 52% of the population, with episodes of incontinence occurring daily in 20-27% of affected persons. UI after spinal cord injury (SCI) is a major cause of distress and morbidity amongst patients with SCI, and is associated with decreased quality of life in general, physical, and emotional domains. UI has the undesirable side effects of perineal irritation and infection, increased odor, disrupted sleep, embarrassment, need to change clothes/bedding, and sexual dysfunction, as well as significant financial burden. Persons living with a SCI have ranked urinary problems as the most important health problem after injury. Addressing this significant problem and providing relief has the potential to significantly improve the lives of patients with SCI.
Typical treatment options are geared toward the type of UI in each patient. For stress UI, the goal of treatment is to provide support to the pelvic floor and urethra. Pessaries (devices placed inside the vagina in women) or surgery (e.g. suburethral sling) to elevate the urethra and/or bladder neck to increase the resistance to leak through the urethra are commonly used. Urethral bulking agents or pelvic muscle floor therapy are also employed to strengthen the closure pressure of the urethra in patients with stress UI. No pharmacologic agents are currently available to treat stress UI. For urge UI, medications or electrical stimulation aimed at relaxation of the detrusor muscle, including anticholinergics, are used. For overflow or obstructive UI, treatments are aimed at shrinking or removing the obstruction, such as medications to shrink the prostate, prostatectomy or mass removal. For neurogenic UI, surgery for diversion or implant placement may be utilized.
Sildenafil (Viagra) has been well studied and used extensively in males to treat erectile dysfunction. Phosphodiesterase 5 (PDE5) inhibitors, including sildenafil, are potent vasodilators that enhance tissue perfusion, relax smooth muscle of the vasculature and bladder, and stimulate skeletal muscle protein synthesis. It has been reported to improve lower urinary tract symptoms, including urge UI and benign prostatic hyperplasia (BPH) in men. In our team's recent study using sildenafil for treatment of UI in women, the investigators found improvement in quality of life and a decrease in the number of incontinence episodes in women taking sildenafil. Higher sildenafil plasma levels were associated with greater improvement in symptoms. While the types of UI in women are somewhat different than in men, studies have shown improvements in UI in both sexes.
Thus, the investigators propose to conduct a two month randomized, placebo-controlled crossover trial of sildenafil in male and female adult SCI patients with UI to assess the therapeutic potential of sildenafil to reduce the symptoms of urinary leakage.
Aims:
Aim 1: To determine whether sildenafil will decrease episodes of leakage of UI in adult women and men with SCI.
Aim 2: To determine the effects of sildenafil on the subjective measures of UI, including quality of life.
Experimental Protocol:
Investigators will study patients with spinal cord injuries (aged 18-70) with current urine leakage of more than 3 times/week (n=24). Subjects will undergo a double blinded randomized cross over treatment of sildenafil (20mg TID) and placebo. Each treatment period will last 4 weeks with a 2 week washout between treatment periods.
Before and after each treatment period, subjects will undergo testing which will consist of measurements of urine post void residual volume (PVR), adverse event assessment, and questionnaires of quality of life and urinary health.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Crossover
- Masking
- Triple blind (participant, investigator, outcomes assessor)
- Number of arms
- 2
- Model description
- Each subject will be administered both sildenafil 20mg TID for 4 weeks and placebo (lactose) TID for 4 weeks in a crossover fashion with a 2 week washout period between treatments.
| Arm | Type | Receives |
|---|---|---|
| Sildenafil 20mg TID then Placebo TID | Experimental | Drug: Sildenafil Citrate, Drug: PlaceboSubjects will be administered Sildenafil 20mg TID for 4 weeks. There will be a 2 week washout period then subjects will be administered Placebo (lactose) TID for 4 weeks. |
| Placebo TID then Sildenafil 20mg TID | Experimental | Drug: Sildenafil Citrate, Drug: PlaceboSubjects will be administered Placebo (lactose) TID for 4 week. There will be a 2 week washout period and then subjects will be administered Sildenafil 20mg TID for 4 weeks. |
Who may qualify
- Ages
- 18 to 70 years
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (5 listed)
- Adults with spinal cord injury (SCI), 18-75 years of age, at the time of consent
- Have urinary incontinence (UI), with at least 3 leakage episodes/week
- Have urodynamics assessment on file with their provider in past 3 years. If no historical data on file, subject may complete prior to study visit 1.
- Willing and able to comply with study procedures
- Willing and able to provide written informed consent
Key exclusion criteria (15 listed)
- In phone prescreen, delighted or pleased with current quality of life due to urinary symptoms.
- Indwelling catheter
- History of greater than 4 urinary tract infections per year
- Multiple sclerosis
- Significant heart, liver, kidney, pulmonary, blood, autoimmune or peripheral vascular disease
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 |
|---|---|---|
| Sildenafil CitrateAlso: RevatioSildenafil 20mg TID for 4 weeks | Drug | Placebo TID then Sildenafil 20mg TID, Sildenafil 20mg TID then Placebo TID |
| PlaceboAlso: LactosePlacebo (Lactose) TID for 4 weeks | Drug | Placebo TID then Sildenafil 20mg TID, Sildenafil 20mg TID then Placebo TID |
Primary outcome
Bladder Leakage as measured by 5 day bladder diary at Baseline
Time frame: baseline
Bladder leakage will be measured by bladder diary, which will be kept for five- 24 hours periods at baseline. Subjects will be asked to record the number of leaks each day. Data will be calculated by summing total number of leaks over the 5 day recording period and dividing the sum by 5, resulting in average leaks per day.
Bladder Leakage as measured by 5 day bladder diary after 4 weeks of Sildenafil Treatment
Time frame: after 4 weeks of sildenafil treatment
Bladder leakage will be measured by bladder diary, which will be kept for five 24 hours periods in the last week of the 4 weeks of sildenafil treatment.
Bladder Leakage as measured by 5 day bladder diary after 4 weeks of Placebo Treatment
Time frame: after 4 weeks of placebo treatment
Bladder leakage will be measured by bladder diary, which will be kept for five 24 hours periods in the last week of the 4 weeks of placebo treatment.
18 secondary outcomes
Blood sildenafil levels as measured by Liquid Chromatography Mass Spectrometry (LCMS) at baseline
Time frame: baseline
Blood sildenafil levels as measured by Liquid Chromatography Mass Spectrometry (LCMS) after 4 weeks of sildenafil treatment
Time frame: after 4 weeks of sildenafil treatment
Blood sildenafil levels as measured by Liquid Chromatography Mass Spectrometry (LCMS) after 4 weeks of placebo treatment
Time frame: after 4 weeks of placebo treatment
Post void residual urine volume as measured by ultrasound bladder scanner at baseline
Time frame: baseline
Post void residual urine volume as measured by ultrasound bladder scanner after 4 weeks of sildenafil treatment
Time frame: after 4 weeks of sildenafil treatment
Post void residual urine volume as measured by ultrasound bladder scanner after 4 weeks of placebo treatment
Time frame: after 4 weeks of placebo treatment
Urinary symptoms as measured by the American Urological Association Symptom Score at baseline
Time frame: baseline
Urinary symptoms as measured by the American Urological Association Symptom Score after 4 weeks of sildenafil treatment
Time frame: after 4 weeks of sildenafil treatment
Urinary symptoms as measured by the American Urological Association Symptom Score after 4 weeks of placebo treatment
Time frame: after 4 weeks of placebo treatment
Bladder dysfunction as measured by the Neurogenic Bladder Symptom Score at baseline
Time frame: baseline
Bladder dysfunction as measured by the Neurogenic Bladder Symptom Score after 4 weeks of sildenafil treatment
Time frame: after 4 weeks of sildenafil treatment
Bladder dysfunction as measured by the Neurogenic Bladder Symptom Score after 4 weeks of placebo treatment
Time frame: after 4 weeks of placebo treatment
Perception of bladder conditions as measured by the Patient Perception of Bladder Symptoms questionnaire at baseline
Time frame: baseline
Perception of bladder conditions as measured by the Patient Perception of Bladder Symptoms questionnaire after 4 weeks of sildenafil treatment
Time frame: after 4 weeks of sildenafil treatment
Perception of bladder conditions as measured by the Patient Perception of Bladder Symptoms questionnaire after 4 weeks of placebo treatment
Time frame: after 4 weeks of placebo treatment
Urinary Symptoms Interference as measured by Pelvic Floor Impact Questionnaire at baseline
Time frame: baseline
Urinary Symptoms Interference as measured by Pelvic Floor Impact Questionnaire after 4 weeks of sildenafil treatment
Time frame: after 4 weeks of sildenafil treatment
Urinary Symptoms Interference as measured by Pelvic Floor Impact Questionnaire after 4 weeks of placebo treatment
Time frame: after 4 weeks of placebo treatment
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 9 Sep 2026.
- Individual participant dataSharing planned: No
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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. This study is not recruiting at the moment.
Kathy Vincent, MD principal investigator
University of Texas
2 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Sildenafil Citrate in people with Spinal Cord Injuries and Urinary Incontinence, run by The University of Texas Medical Branch, Galveston at 2 sites in United States.
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 5 inclusion and 15 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: under way, not looking for participants, as of the sponsor's last update on 9 Sep 2026. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 2 sites in United States. 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 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
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?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Bladder Leakage as measured by 5 day bladder diary at Baseline (time frame: baseline). The study lists 3 primary outcomes in all. 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 9 Sep 2026.