Erectile DysfunctionNCT06720597
EndoPAT Device for Endothelial Dysfunction in ED
A study testing Daily low-dose PDE5 inhibitor therapy and Testosterone therapy as per clinical guidelines. in people with Erectile Dysfunction and Hypogonadism, Male, run by University of California, Irvine at 1 site in United States.
Trial summary
To assess endothelial dysfunction in young men (aged 30-50) with vasculogenic ED identified through penile Doppler ultrasound. To evaluate changes in endothelial function using EndoPAT before and 3-6 months after daily low-dose phosphodiesterase type 5 (PDE5) inhibitor therapy. Read more about this study
- Who is it for?
- Ages 18 years and older, men only
- Conditions the study is for
- Erectile Dysfunction, Hypogonadism, Male, Endothelial Dysfunction
- What is being tested?
- Daily low-dose PDE5 inhibitor therapy and Testosterone therapy as per clinical guidelines.
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 120 participants
- Where
- 1 siteUnited States
- Study dates
- 13 Aug 2025to Jan 2027
- Phase
- Interventional
- 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 years and older
- Men only
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Males 18 years old and above
- Diagnosed with erectile dysfunction or hypogonadism
Who cannot join
- Patients without the above criteria
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
United States1 site, 1 recruiting
- Recruiting
UCI Urology | Men's Health Center
Newport Beach, California, 92660
Muhammed AM Hammad, Mbbch, 7144567005, mahammad@hs.uci.edu
Elia Abou Chawareb, MD, 7144567005, eaboucha@hs.uci.edu
About this study
Official title: Utilizing EndoPAT Device for Endothelial Dysfunction Assessment in Erectile Dysfunction and Hormonal Therapy
To assess endothelial dysfunction in young men (aged 30-50) with vasculogenic ED identified through penile Doppler ultrasound.
To evaluate changes in endothelial function using EndoPAT before and 3-6 months after daily low-dose phosphodiesterase type 5 (PDE5) inhibitor therapy.
To investigate endothelial function alterations in hypogonadal patients before and 3-6 months after initiating testosterone (T) therapy
Read the detailed description
Endothelial Dysfunction and Cardiovascular Health: Endothelial dysfunction is characterized by impaired endothelium-dependent vasodilation, which is a critical factor in the development and progression of cardiovascular diseases. The endothelium, the thin layer of cells lining blood vessels, plays a pivotal role in vascular health by regulating blood flow, coagulation, and immune function. When the endothelium is not functioning properly, it can lead to a range of cardiovascular conditions, including atherosclerosis, hypertension, and erectile dysfunction (ED).
Erectile Dysfunction and Endothelial Dysfunction: ED is often an early marker of endothelial dysfunction and cardiovascular diseases. Vasculogenic ED, in particular, is linked to poor endothelial health, where impaired blood flow to the penile tissue results in the inability to achieve or maintain an erection. This condition shares common risk factors with other cardiovascular diseases, such as diabetes, hypertension, and hyperlipidemia, highlighting the interconnected nature of endothelial health and ED.
Hormonal Therapy and Endothelial Function: Testosterone therapy (T therapy) is commonly used to treat hypogonadism in men, a condition characterized by low testosterone levels. Hypogonadism itself is associated with an increased risk of cardiovascular diseases, and testosterone therapy has been shown to have varying effects on endothelial function. While some studies suggest that testosterone may improve endothelial health, others indicate potential risks, necessitating further research to clarify its impact.
Current Gaps in Knowledge:
Prevalence of Endothelial Dysfunction in Young Men with ED: While the association between endothelial dysfunction and ED is established, there is a need for precise data on the prevalence and extent of endothelial dysfunction specifically in young men with vasculogenic ED. Understanding this prevalence can inform targeted treatment strategies.
Impact of PDE5 Inhibitors on Endothelial Function: Phosphodiesterase type 5 (PDE5) inhibitors are a first-line treatment for ED, known to improve erectile function by enhancing blood flow. However, their direct impact on endothelial function over time remains underexplored, particularly in terms of long-term cardiovascular outcomes.
Effects of Testosterone Therapy on Endothelial Health: The influence of testosterone therapy on endothelial function in hypogonadal men is not well understood. There is conflicting evidence on whether testosterone therapy confers cardiovascular benefits or risks, necessitating comprehensive studies to determine its effects.
- Being tested
- Daily low-dose PDE5 inhibitor therapy, Testosterone therapy as per clinical guidelines.
- Keywords
- EndoPAT, Erectile Dysfunction, Hypogonadism, Endothelial Dysfunction, ED, Testosterone
- Medical subject headings
- Erectile Dysfunction, Eunuchism, Hypogonadism
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Daily low-dose PDE5 inhibitor therapyDrug
Neither arm of the study includes a control group, and the two interventions will not be compared directly. The primary objective is to evaluate endothelial function using the EndoPAT device at baseline, 3 months, and 6 months following the intervention in each arm.
Testosterone therapy as per clinical guidelines.Drug
Neither arm of the study includes a control group, and the two interventions will not be compared directly. The primary objective is to evaluate endothelial function using the EndoPAT device at baseline, 3 months, and 6 months following the intervention.
| Study group | Role | What they receive |
|---|---|---|
| PDE5 Inhibitor Therapy in Men with Vasculogenic Erectile Dysfunction (ED) | Active comparator | Population: 40 men aged 18 or above years diagnosed with vasculogenic ED. Intervention: Daily low-dose PDE5 inhibitor therapy. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. Receives: Drug: Daily low-dose PDE5 inhibitor therapy |
| Testosterone Therapy in Hypogonadal Men | Active comparator | Population: 40 hypogonadal men aged 18 or above Intervention: Testosterone therapy as per clinical guidelines. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. Receives: Drug: Testosterone therapy as per clinical guidelines. |
| Vasculogenic ED confirmed by penile Doppler ultrasound | No intervention | Population: 40 men aged 18 or above years diagnosed with vasculogenic ED. Intervention: None Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. |
What is being measured
The primary outcome is the main question the study is designed to answer.
Endothelial Function as Measured by Reactive Hyperemia Index (RHI)
Definition: RHI is a measure of endothelial function derived from the EndoPAT device, which assesses the endothelium's ability to respond to induced hyperemia.
Measurement: RHI is calculated based on the changes in digital pulse volume during reactive hyperemia following a 5-minute arterial occlusion.
Criteria for Evaluation:
Baseline RHI: Measured before any intervention. Post-Intervention RHI: Measured at 3 months and 6 months post-intervention. Improvement in RHI: Defined as an increase in RHI scores from baseline to follow-up measurements.
Measured: At baseline, 3 months, and 6 months post-intervention
Secondary outcomes (3)
Cardiovascular Health Markers
Successful Outcome: Statistically significant improvements in blood pressure, lipid profile, and blood glucose levels from baseline to 3 and 6 months.
Failure: No significant changes or worsening of cardiovascular health markers.
Measured: From baseline to 3 months and 6 months post-intervention.
Sexual Function Scores
Successful Outcome: Statistically significant improvement in IIEF scores from baseline to 3 and 6 months.
Failure: No significant changes or deterioration in sexual function scores.
Measured: From baseline to 3 months and 6 months post-intervention.
Adverse Events
Successful Outcome: Minimal and non-severe adverse events reported. Failure: High frequency or severe adverse events necessitating discontinuation of the intervention.
Measured: From baseline to 3 months and 6 months post-intervention.
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Dec 2024
- Study start13 Aug 2025
- Primary completionJan 2027 (estimated)
- Study completionJan 2027 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Other trials for Erectile DysfunctionStudies of the same condition, open and under way.
- 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 N/A
- Primary purpose
- Diagnosis
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Model description
- Study groups: 1. Vasculogenic ED confirmed by penile Doppler ultrasound Population: 40 men aged 18 or above years diagnosed with vasculogenic ED Intervention: None. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. 2. PDE5 Inhibitor Therapy in Men with Vasculogenic Erectile Dysfunction (ED) Population: 40 men aged 18 or above years diagnosed with vasculogenic ED. Intervention: Daily low-dose PDE5 inhibitor therapy. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. 3. Testosterone Therapy in Hypogonadal Men Population: 40 hypogonadal men aged 18 or above Intervention: Testosterone therapy as per clinical guidelines. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention.
- Masking
- None (open label)
- Enrolment
- 120 participants (estimated)
Sponsor and investigators
- Lead sponsor
- University of California, Irvine
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, Faysal Yafi, University of California, Irvine
- Investigators
- Faysal A Yafi, MD, Principal investigator, University of California, Irvine
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT06720597
- Sponsor's protocol ID
- 5526
- Status last verified
- Jan 2026
- First submitted
- 2 Dec 2024
- Last updated
- 2 Feb 2026
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- No
Study at a glance
From the registry record, last updated by the sponsor on 2 Feb 2026. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Utilizing EndoPAT Device for Endothelial Dysfunction Assessment in Erectile Dysfunction and Hormonal Therapy
- ClinicalTrials.gov ID
- NCT06720597
- Acronym / sponsor ID
- 5526
- Keywords
- EndoPAT, Erectile Dysfunction, Hypogonadism, Endothelial Dysfunction, ED, Testosterone
- Study type
- Interventional
- Recruitment status
- Recruiting
- Enrolment
- 120 participants (estimated)
- Lead sponsor
- University of California, IrvineUniversity, hospital or other
- Study start
- 13 Aug 2025 (actual)
- Primary completion
- Jan 2027 (estimated)
- Study completion
- Jan 2027 (estimated)
- First posted
- 6 Dec 2024 (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.
To assess endothelial dysfunction in young men (aged 30-50) with vasculogenic ED identified through penile Doppler ultrasound.
To evaluate changes in endothelial function using EndoPAT before and 3-6 months after daily low-dose phosphodiesterase type 5 (PDE5) inhibitor therapy.
To investigate endothelial function alterations in hypogonadal patients before and 3-6 months after initiating testosterone (T) therapy
Detailed description
Endothelial Dysfunction and Cardiovascular Health: Endothelial dysfunction is characterized by impaired endothelium-dependent vasodilation, which is a critical factor in the development and progression of cardiovascular diseases. The endothelium, the thin layer of cells lining blood vessels, plays a pivotal role in vascular health by regulating blood flow, coagulation, and immune function. When the endothelium is not functioning properly, it can lead to a range of cardiovascular conditions, including atherosclerosis, hypertension, and erectile dysfunction (ED).
Erectile Dysfunction and Endothelial Dysfunction: ED is often an early marker of endothelial dysfunction and cardiovascular diseases. Vasculogenic ED, in particular, is linked to poor endothelial health, where impaired blood flow to the penile tissue results in the inability to achieve or maintain an erection. This condition shares common risk factors with other cardiovascular diseases, such as diabetes, hypertension, and hyperlipidemia, highlighting the interconnected nature of endothelial health and ED.
Hormonal Therapy and Endothelial Function: Testosterone therapy (T therapy) is commonly used to treat hypogonadism in men, a condition characterized by low testosterone levels. Hypogonadism itself is associated with an increased risk of cardiovascular diseases, and testosterone therapy has been shown to have varying effects on endothelial function. While some studies suggest that testosterone may improve endothelial health, others indicate potential risks, necessitating further research to clarify its impact.
Current Gaps in Knowledge:
Prevalence of Endothelial Dysfunction in Young Men with ED: While the association between endothelial dysfunction and ED is established, there is a need for precise data on the prevalence and extent of endothelial dysfunction specifically in young men with vasculogenic ED. Understanding this prevalence can inform targeted treatment strategies.
Impact of PDE5 Inhibitors on Endothelial Function: Phosphodiesterase type 5 (PDE5) inhibitors are a first-line treatment for ED, known to improve erectile function by enhancing blood flow. However, their direct impact on endothelial function over time remains underexplored, particularly in terms of long-term cardiovascular outcomes.
Effects of Testosterone Therapy on Endothelial Health: The influence of testosterone therapy on endothelial function in hypogonadal men is not well understood. There is conflicting evidence on whether testosterone therapy confers cardiovascular benefits or risks, necessitating comprehensive studies to determine its effects.
Study design
- Primary purpose
- Diagnosis
- Allocation
- Non-randomised
- Intervention model
- Parallel groups
- Masking
- None (open label)
- Number of arms
- 3
- Model description
- Study groups: 1. Vasculogenic ED confirmed by penile Doppler ultrasound Population: 40 men aged 18 or above years diagnosed with vasculogenic ED Intervention: None. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. 2. PDE5 Inhibitor Therapy in Men with Vasculogenic Erectile Dysfunction (ED) Population: 40 men aged 18 or above years diagnosed with vasculogenic ED. Intervention: Daily low-dose PDE5 inhibitor therapy. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. 3. Testosterone Therapy in Hypogonadal Men Population: 40 hypogonadal men aged 18 or above Intervention: Testosterone therapy as per clinical guidelines. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention.
| Arm | Type | Receives |
|---|---|---|
| PDE5 Inhibitor Therapy in Men with Vasculogenic Erectile Dysfunction (ED) | Active comparator | Drug: Daily low-dose PDE5 inhibitor therapyPopulation: 40 men aged 18 or above years diagnosed with vasculogenic ED. Intervention: Daily low-dose PDE5 inhibitor therapy. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. |
| Testosterone Therapy in Hypogonadal Men | Active comparator | Drug: Testosterone therapy as per clinical guidelines.Population: 40 hypogonadal men aged 18 or above Intervention: Testosterone therapy as per clinical guidelines. Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. |
| Vasculogenic ED confirmed by penile Doppler ultrasound | No intervention | –Population: 40 men aged 18 or above years diagnosed with vasculogenic ED. Intervention: None Assessments: Endothelial function will be assessed using the EndoPAT device at baseline, 3 months, and 6 months post-intervention. |
Who may qualify
- Ages
- 18 years and older
- Sex
- Male only
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (2 listed)
- Males 18 years old and above
- Diagnosed with erectile dysfunction or hypogonadism
Key exclusion criteria (1 listed)
- Patients without the above criteria
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 |
|---|---|---|
| Daily low-dose PDE5 inhibitor therapyNeither arm of the study includes a control group, and the two interventions will not be compared directly. The primary objective is to evaluate endothelial function using the EndoPAT device at baseline, 3 months, and 6 months following the intervention in each arm. | Drug | PDE5 Inhibitor Therapy in Men with Vasculogenic Erectile Dysfunction (ED) |
| Testosterone therapy as per clinical guidelines.Neither arm of the study includes a control group, and the two interventions will not be compared directly. The primary objective is to evaluate endothelial function using the EndoPAT device at baseline, 3 months, and 6 months following the intervention. | Drug | Testosterone Therapy in Hypogonadal Men |
Primary outcome
Endothelial Function as Measured by Reactive Hyperemia Index (RHI)
Time frame: At baseline, 3 months, and 6 months post-intervention
Definition: RHI is a measure of endothelial function derived from the EndoPAT device, which assesses the endothelium's ability to respond to induced hyperemia. Measurement: RHI is calculated based on the changes in digital pulse volume during reactive hyperemia following a 5-minute arterial occlusion. Criteria for Evaluation: Baseline RHI: Measured before any intervention. Post-Intervention RHI: Measured at 3 months and 6 months post-intervention. Improvement in RHI: Defined as an increase in RHI scores from baseline to follow-up measurements.
3 secondary outcomes
Cardiovascular Health Markers
Time frame: From baseline to 3 months and 6 months post-intervention.
Sexual Function Scores
Time frame: From baseline to 3 months and 6 months post-intervention.
Adverse Events
Time frame: From baseline to 3 months and 6 months post-intervention.
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 2 Feb 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.
Faysal A Yafi, MD principal investigator
University of California, Irvine
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing Daily low-dose PDE5 inhibitor therapy and Testosterone therapy as per clinical guidelines. in people with Erectile Dysfunction and Hypogonadism, Male, run by University of California, Irvine at 1 site 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 2 inclusion and 1 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 2 Feb 2026. 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 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.
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 Muhammed AM Hammad, MBBCh (714-456-7005, mahammad@hs.uci.edu), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Endothelial Function as Measured by Reactive Hyperemia Index (RHI) (time frame: At baseline, 3 months, and 6 months post-intervention). 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 2 Feb 2026.