A Systematic Review of Human Trials Using Stem Cell Therapy for Erectile Dysfunction

Abstract

Introduction Novel therapeutic modalities have been proposed for the treatment and management of erectile dysfunction (ED). Stem cell therapy (SCT) is the injection of mesenchymal stem cells or stromal vascular fractions from adipose and other tissue sources. Although SCT has been studied and reported in multiple rodent trials, few human clinical trials exist. Aim The aim of this study was to provide a systematic review of SCT for the treatment of ED with an emphasis on data from peer-reviewed human studies. Methods A systematic review was performed evaluating SCT for ED in human studies using PubMed-Medline and Scopus databases. Literature search was conducted using key words such as “Clinical Trials of SCT for ED,” “Stromal Vascular Fraction Treatment for ED,” and “SCT for ED.” Systematic review followed Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Main Outcome Measure The main outcomes measure was the safety and efficacy of SCT for ED in humans. Results 5 studies specific to SCT for ED treatment were included. A total of 61 patients were included in these phase I and II clinical trials and follow-up periods ranged from 6−62 months. End points of the studies included safety, tolerability, and efficacy of SCT for ED. The majority of the studies demonstrated improvement in erectile function due to SCT in patients, including improvements in penile vascular flow, International Index of Erectile Function-15 items, and Erectile Hardness Scale scores. All of the studies reported that there were no serious adverse events for patients. Limitations of the studies included small cohort sizes, and only 1 contained a sham arm. Conclusion The 5 completed human clinical trials show promise for SCT as a restorative therapy for the treatment of ED. However, although promising, there still exists very limited data for the use of SCT for ED in humans. With the expansion of clinics offering SCT for ED, it is imperative that SCT is investigated further for safety, efficacy, and standardization.

A case report of pudendal arteries angioplasty with sirolimus drug-coated balloon and drug-eluting stent associated with intracavernous autologous peripheral blood mononuclear cells injection for untreatable vasculogenic erectile dysfunction

“… 6 Furthermore, no complications or bleeding have been reported for other cell therapies injected into the corpora cavernosa. 3 , 16 …”

Restorative Therapies for Erectile Dysfunction: Position Statement From the Sexual Medicine Society of North America (SMSNA)

“…Though preclinical data for SCT and SVF are promising and have led to important discoveries about the mechanisms of erectile tissue regeneration, clinical trial data in humans is limited 47 , 48 ( Table 1 ). There have been several small studies using similar protocols and patient populations.…”

Canadian Urological Association guideline: Erectile dysfunction

“…Stem cells function to release growth factors, cytokines, and chemokines in a paracrine fashion to promote wound healing and rebuild damaged tissues 127 . There have been several small phase I-III human trials evaluating SCT for treating ED, but there is significant variability between protocols, inadequate adverse event reporting, and a lack of long-term follow-up [128][129][130][131] .…”