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

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.

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.