Erectile dysfunction (ED) is a multifactorial disorder mainly due to endothelial dysfunction and reduced blood flow. Multiple modalities are involved in the management algorithm of ED however penile prosthesis is the last resort. Platelet-rich plasma (PRP) is a biological component shown to be beneficial for different conditions due to the presence of many growth factors with its angiogenic and regenerative properties. Moreover, stem cell therapy emerges as a potential therapy and has been used in many conditions and diseases due to its paracrine effect. In our study, we aim to compare the efficacy and safety of a single high-dose PRP intracavernous injection and a single dose of adipose stem cells (ADSC) in patients with severe ED refractory to medical therapies.

Between January 2020 and August 2022, we performed a randomized trial testing the treatment of ED in two groups of a total of 20 patients who have severe ED refractory to conventional medical therapies. Group A (n=10) received a single high-dose single intracavernosal injection of PRP and group B (n=10) received a single intracavernosal injection of ADSC. Liposuction was performed from the treatment group to isolate ASCs. Briefly, the lipoaspirate was digested with collagenase, at 37 °C. Then it was washed 3 times with cold phosphate-buffered saline (PBS). The Stromal vascular fraction was plated into a culture flask. The medium was replaced every 3 days and cultured in expansion. The cells are used after confluence in the first passage. 

Erectile function (EF) was tested using the ‘abridged 5-item version of the International Index of Erectile Function (IIEF-5). EF was assessed at the beginning of the trial, 1, 3, and 6 months of study follow-up. The degree of the erection was categorized based on the IIEF-5 questionnaire and classified as severe dysfunction (score 5-7), moderate ED (score 8–11), mild-moderate (12-16), mild ED (score 17–21), no ED (score 22-25).

The study was approved by our hospital IRB (approval No. 2019.11). Informed consent was confirmed by the IRB. This trial was registered in the UMIN clinical trial registry (UMIN clinical trial registry (UMIN000049397).

Following ADSCs and PRP administration, the EF was improved in all patients at 6 months. One month after therapy, only the patients in group B had an increase in their IEF-5 score to the moderate range. At 3 and 6 months, in group B, the degree of ED was mild in all patients. In group A, for patients treated only with PRP, the ED was moderate at 3 and 6 months (table 1).
No significant side effects during the administration of ADSCs or PRP were reported by the patients from both groups. Tow third of the patients felt a minor pain at the time of injection that resolved the next day without the use of any analgesics

Our study reports that a single intracavernosal injection of ADSC or PRP could improve ED  progressively during the 6 monthly follow-up period.
More studies addressing the use of ADSCs and PRP for this indication are needed to confirm our findings.
The main limitation of our study is the small sample size and relatively short-term follow-up.

A single intracavernosal injection of ADSCs and PRP may be a promising addition to the urologist's armamentarium for the management of ED.

Continence 7S1 (2023) 101031
DOI: 10.1016/j.cont.2023.101031