Aquablation demonstrated a significantly lower rate of sexual dysfunction at the primary safety endpoint of 3 months compared with transurethral resection of the prostate (TURP), according to phase-3 data.
The 2-year outcomes of the WATER study were presented by Dr. Neil Barber (Frimley Health NHS Foundation Trust, UK) [1]. This study compared the safety and efficacy of prostate ablation using aquablation therapy (robotic heat-free waterjet prostate resection) with TURP for lower urinary tract symptoms (LUTS) due to benign prostatic hyperplasia (BPH).
In this randomized, double-blinded, global multicentre phase 3 trial, 184 men with moderate-to-severe LUTS related to BPH were assigned to aquablation therapy (n=117) or TURP (n=67). The baseline characteristics of patients in both arms were comparable, with no significant differences. The trial had a co-primary safety and efficacy endpoint designed to show noninferiority regarding efficacy: the proportion of subjects with adverse events rated as probably or definitely related to the study procedure classified as Clavien-Dindo Grade 2 or higher, or any Grade 1 event resulting in persistent disability (e.g. ejaculatory disorder or erectile dysfunction), evidenced through 3 months post-treatment, together with the primary efficacy endpoint of the International Prostate Symptom Score’s (IPSS) change score from baseline to 6 months.
Patients and assessors were blinded to treatment. Data was collected using the IPSS, Male Sexual Health Questionnaire (MSHQ), the International Index of Erectile Function (IIEF), and uroflow.
With two years of follow-up, aquablation therapy shows similar symptom score comparisons and uroflow measurements as compared with TURP, at all time points measured (baseline and 3, 6, 12, and 24 months). Aquablation therapy saw consistent uroflow improvement from 6 months to 2 years. Low retreatment rates were observed for both arms and there were no differences between them. Aquablation and TURP showed no differences with regard to PSA reduction in this period of time. Symptom improvement scores were comparable to other resection techniques.
Aquablation demonstrated a significantly lower rate of sexual dysfunction at the primary safety endpoint of 3 months. The CD1P (measuring incontinence, erectile dysfunction, and ejaculatory dysfunction) was lower in the aquablation arm (6.9% vs 24.6%), which held true when combined with the CD2 score (events requiring pharmacological treatment, blood transfusion, endoscopic, surgical, or radiological intervention; 26.0% vs 42.0%). In conclusion, the results from WATER demonstrate aquablation to be a safe and effective alternative to TURP.
Reference:
1. Barber N et al. Two-year outcomes after aquablation compared to TURP: results from a blinded randomized trial. EAU20 Virtual Congress, 17-26 July 2020, Abstract 201.