Intracavernosal Exosomes vs. Rectal Ozone for Post-RARP Erectile Dysfunction (REHAB-RARP)

July 11, 2026 updated by: Ali Ihsan Memmi, Medipol University

Intracavernosal Exosomes Versus Rectal Ozone Therapy for Erectile Dysfunction Following Robotic-Assisted Radical Prostatectomy

This prospective, randomized, controlled trial aims to evaluate and compare the therapeutic efficacy of intracavernosal urine-derived exosomes and systemic rectal ozone therapy in patients experiencing erectile dysfunction (ED) post-robotic-assisted radical prostatectomy (RARP). Patients will be randomized into two distinct intervention arms. The primary objective is to assess the functional recovery of the erectile tissue via the International Index of Erectile Function (IIEF-5) over a 6-month follow-up period. Secondary endpoints include penile hemodynamic alterations and overall health-related quality of life.

Study Overview

Status

Not yet recruiting

Conditions

Intervention / Treatment

Detailed Description

Erectile dysfunction (ED) remains a prevalent and distressing complication following robotic-assisted radical prostatectomy (RARP), primarily manifesting secondary to cavernous nerve neuropraxia, subsequent localized hypoxia, and fibrotic remodeling of the corpus cavernosum. While standard pharmacotherapies (e.g., PDE5 inhibitors) offer symptomatic relief, they fail to reverse the underlying endothelial and neural detriments.Recent preclinical and clinical data suggest that stem cell-derived therapies, particularly cell-free exosomes, exhibit significant proangiogenic and antifibrotic properties. Extracellular vesicles containing components of the stem cell secretome, such as microRNAs, facilitate endothelial cell proliferation and tissue repair. Conversely, systemic ozone therapy has been hypothesized to enhance oxygen delivery, upregulate antioxidant enzymes, and modulate inflammatory cascades, potentially mitigating post-surgical ischemia. In this trial, eligible post-RARP patients will be randomized (1:1) to receive either a targeted intracavernosal injection of urine-derived exosomes (USC-Exos) or a scheduled regimen of rectal ozone-oxygen mixture insufflation. Erectile capacity, penile vascular hemodynamics (assessed via pharmacopenile duplex ultrasonography), and general health status will be prospectively monitored at baseline, 3, and 6 months post-intervention.

Study Type

Interventional

Enrollment (Estimated)

60

Phase

  • Not Applicable

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Locations

  • Turkey (Türkiye)
    • Başakşehir
      • Istanbul, Başakşehir, Turkey (Türkiye)
        • Başakşehir Çam Sakura City Hospital
        • Contact:
        • Principal Investigator:
          • Ali ihsan Memmi, MD

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

  • Adult
  • Older Adult

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • History of Robotic-Assisted Radical Prostatectomy (ns-RARP) for localized prostate cancer.
  • Normal preoperative erectile function (retrospective IIEF-5 score > 21).
  • Presence of a stable, sexually active heterosexual relationship.
  • Inadequate response or intolerance to maximum dose, on-demand oral Phosphodiesterase type 5 inhibitors (PDE5i).

Exclusion Criteria:

  • History of adjuvant or salvage pelvic radiotherapy / androgen deprivation therapy (ADT).
  • Presence of severe anatomical penile deformities (e.g., active phase Peyronie's disease).
  • Uncontrolled endocrinological (e.g., HbA1c > 8.5%) or cardiovascular comorbidities.
  • History of major cardiovascular events (myocardial infarction, stroke) within the preceding 6 months.
  • Current use of systemic anticoagulants (excluding low-dose prophylactic aspirin).
  • Concomitant use of any intraurethral alprostadil, vacuum erection devices (VED), or testosterone replacement therapy during the study period.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: None (Open Label)

Arms and Interventions

Participant Group / Arm
Intervention / Treatment
Experimental: Intracavernosal Urine-Derived Exosomes (USC-Exos)
Participants randomized to this arm will receive targeted intracavernosal injections of cell-free, urine-derived exosomes. The intervention aims to evaluate the proangiogenic and regenerative effects of the exosome secretome on the cavernous tissue following radical prostatectomy.
Biological: Urine-Derived Exosomes (USC-Exos)
A single (or protocol-specified sequenced) bilateral intracavernosal injection of a sterile, cell-free urine-derived exosome suspension (e.g., 2 cc) into the corpus cavernosum, performed under clinical setting conditions.
Experimental: Rectal Medical Ozone Therapy
Participants randomized to this arm will receive protocolized systemic rectal medical ozone insufflation. This arm evaluates the systemic antioxidant, anti-inflammatory, and tissue oxygenation benefits of ozone therapy on post-operative erectile functional recovery.
Procedure: Rectal Medical Ozone Insufflation
Administration of a standardized medical ozone and oxygen gas mixture (e.g., 30-40 µg/mL concentration) via rectal insufflation. The treatment will be administered for a predetermined number of sessions (e.g., 10 sessions spanning over 5 weeks) using a certified medical ozone generator.
Active Comparator: Standard Penile Rehabilitation
Participants randomized to this arm will receive the current standard of care for post-prostatectomy penile rehabilitation. This serves as the active control group to benchmark the efficacy of the experimental regenerative therapies.
Drug: Daily Phosphodiesterase type 5 (PDE5) Inhibitor
Oral administration of a daily low-dose PDE5 inhibitor (e.g., Tadalafil 5 mg once daily) for a continuous duration of 6 months, aligning with standard clinical guidelines for post-operative erectile dysfunction management.

What is the study measuring?

Primary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Mean Change in International Index of Erectile Function (IIEF-5) Score
Time Frame: Baseline, 3 Months Post-Intervention, and 6 Months Post-Intervention.
The International Index of Erectile Function (IIEF-5) is a validated self-reporting psychometric instrument utilized to assess erectile function severity. The total score ranges from a minimum of 5 to a maximum of 25. Higher scores represent better erectile function (a better outcome), with scores ≤21 indicating varying degrees of erectile dysfunction and 22-25 representing normal erectile function.
Baseline, 3 Months Post-Intervention, and 6 Months Post-Intervention.

Secondary Outcome Measures

Outcome Measure
Measure Description
Time Frame
Change in Peak Systolic Velocity (PSV)
Time Frame: Baseline and 6 Months Post-Intervention.
Objective measurement of cavernous arterial competence following an intracavernosal injection of a vasoactive agent, assessed via Pharmacopenile Duplex Ultrasonography (PPDU). Reported in centimeters per second (cm/s).
Baseline and 6 Months Post-Intervention.
Change in End-Diastolic Velocity (EDV)
Time Frame: Baseline and 6 Months Post-Intervention.
Objective measurement of the cavernous veno-occlusive mechanism following an intracavernosal injection of a vasoactive agent, assessed via Pharmacopenile Duplex Ultrasonography (PPDU). Reported in centimeters per second (cm/s).
Baseline and 6 Months Post-Intervention.
Change in Resistive Index (RI)
Time Frame: Baseline and 6 Months Post-Intervention.
Calculated ratio based on the peak systolic and end-diastolic velocities, used to evaluate penile vascular resistance via Pharmacopenile Duplex Ultrasonography (PPDU). It is reported as a unitless ratio.
Baseline and 6 Months Post-Intervention.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Medipol University

Collaborators

Istanbul Medipol University Hospital
Başakşehir Çam & Sakura City Hospital

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

August 1, 2026

Primary Completion (Estimated)

January 1, 2027

Study Completion (Estimated)

April 1, 2027

Study Registration Dates

First Submitted

May 17, 2026

First Submitted That Met QC Criteria

July 11, 2026

First Posted (Actual)

July 16, 2026

Study Record Updates

Last Update Posted (Actual)

July 16, 2026

Last Update Submitted That Met QC Criteria

July 11, 2026

Last Verified

July 1, 2026

More Information

Terms related to this study

Keywords

Additional Relevant MeSH Terms

Other Study ID Numbers

  • 1453145315453

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

No

Studies a U.S. FDA-regulated device product

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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