Variability in Methodology of Erectile Dysfunction Regenerative Therapy Trials on ClinicalTrials.gov.

ABSTRACT

OBJECTIVE: To evaluate the variability in the criteria of erectile dysfunction (ED) regenerative therapy trials registered on ClinicalTrials.gov. METHODS: Interventional trials on ClinicalTrials.gov with the keywords "erectile dysfunction" and variations of "shockwave," "platelet rich plasma," "stem cell," "regenerative," and "restorative" were examined. Inclusion/exclusion criteria and primary/secondary outcomes were compared between extracorporeal shockwave therapy (ESWT), platelet rich plasma and stem cell injections (PRP/SC), and other regenerative therapies (ORT) groups. RESULTS: Of the 92 trials analyzed, International Index of Erectile Function (IIEF) score was the most common primary outcome (72%), with a higher prevalence in ESWT trials than PRP/SC or ORT trials (89% vs 44% and 58%, P <.001). Safety/tolerability was a primary outcome for 44% of PRP/SC trials and 25% of ORT trials but no ESWT trials (P <.001). ESWT trials more frequently had sexual/romantic relationship-based inclusion criteria and cancer treatment-related exclusion criteria than PRP/SC and ORT trials. CONCLUSION: There is substantial variability in the inclusion/exclusion criteria and outcome measures among ED regenerative therapy trials. ESWT trials most frequently utilized IIEF and had the strictest inclusion/exclusion criteria, suggesting more rigorous and functional outcome-based studies. Conversely, PRP/SC and ORT trials, but not ESWT trials, had safety/tolerability as a primary outcome, likely due to the experimental nature of these therapies. The variability in inclusion/exclusion criteria and outcome measures limits comparison of the various ED regenerative therapies.