Intracavernosal UC-MSC secretome therapy for severe erectile dysfunction: a clinical anatomy pilot study with elastography and Doppler assessment

Introduction: Erectile dysfunction (ED) is often treated with phosphodiesterase type 5 inhibitors (PDE5i). However, some patients do not respond effectively to this treatment, making regenerative therapy a potential alternative. This study aims to evaluate the safety and efficacy of umbilical cord-derived mesenchymal stem cell (UC-MSC) secretome in patients with severe ED who are unresponsive to sildenafil therapy. Methods: In this clinical anatomy pilot study, 15 male patients with severe ED unresponsive to sildenafil were administered intracavernosal injections of 0.5 cc of UC-MSC secretome into each corpus cavernosum at the Andrology Clinic of RSUD Dr. Soetomo (Dr. Soetomo General Academic Hospital) in Surabaya, Indonesia, between January 2024 and May 2024 and at RS Universitas Indonesia between January 2025 and May 2025. Therapy safety was evaluated based on local bleeding, hematoma, infection, and pain, while efficacy was measured using the Erection Hardness Score (EHS), International Index of Erectile Function-5 (IIEF-5), reports of morning erections, stretched penis length (SPL), flaccid penis length (FPL), penis circumference, and Penile Doppler Color Ultrasound to evaluate peak systolic velocity (PSV), resistive index (RI), intima-media thickness (IMT), shear wave elastography (SWE), and strain ratio (SR). Results: Significant improvements were observed in EHS, IIEF-5, morning erections, SPL, FPL, penis circumference, PSV, SWE, and SR after therapy. Pain was temporary and subsided within a few minutes. No significant differences in local bleeding, hematoma, and infection were observed. There was a difference in the IMT of the cavernous artery that was not statistically significant, while RI could not be analyzed. Discussion: These findings suggest that UC-MSC secretome is safe and effective as an alternative therapy for severe ED unresponsive to sildenafil, as evidenced by significant changes in EHS, IIEF-5, morning erections, SPL, FPL, penis circumference, PSV, SWE, and SR post- therapy with the potential for temporary pain. Further research is needed to support the development of regenerative therapy for the treatment of ED unresponsive to conventional treatments.