Abstract: PNFLBA-03
Sources of Funding: WATER was sponsored by PROCEPT BioRobotics. (NCT02505919).

Introduction

Prostate resection for patients with LUTS remains the gold standard for surgical treatment of BPH. Gilling et al. reported a prospective single-arm multicenter trial at 3 centers in Australia and New Zealand with 1-year follow-up on 21 men with a similar profile as WATER. Prostate volume dropped from 57 ml at baseline to 35 ml (P<0.0001). Mean IPSS score improved from 23.0 at baseline to 6.8 at 12 months (P<0.0001) and maximum urinary flow increased from 8.7 mL/sec to 18.3 mL/sec (P<0.0001). There were no important perioperative adverse events. No subject developed urinary incontinence and sexual function was preserved postoperatively. In this report, we compared the safety and efficacy of prostate resection using a high-pressure waterjet vs. electrocautery from the WATER study._x000D_

Methods

In this randomized, double-blind, multicenter phase III trial, patients with moderate-to-severe lower urinary tract symptoms related to benign prostatic hyperplasia were assigned to transurethral resection of the prostate using either standard electrosurgery (TURP) or robotic waterjet (Aquablation)._x000D_ The trial has a co-primary safety and efficacy endpoint designed to show non-inferiority. With a minimum enrollment of 177, the estimated power for safety was 99% and efficacy was 80%. The primary safety endpoint is the occurrence of Clavien-Dindo persistent grade 1 or Grade 2 or higher operative complications at 3 months. The primary efficacy endpoint is the reduction at 6 months in IPSS score. _x000D_

Results

The geographic enrollment from the OUS (Australia, New Zealand, United Kingdom) sites and US sites was 91 and 93 subjects, respectively. The baseline IPSS score (TURP 22.2, Aquablation 22.9, p=0.47), demographic profile (Table 1), and prostate volume (TURP 52.0 mL, Aquablation 54.3 mL, p=0.31) were similar in both arms. Operative time was equivalent between the two groups, but resection time was lower in the Aquablation group (28 vs. 4 minutes, p<.0001). The length of stay and length of stay by geography was similar for both arms that averaged 1.4 days.

Conclusions

The first report of the primary safety and efficacy endpoints will be available and ready for presentation at AUA in May 2017.

Funding

WATER was sponsored by PROCEPT BioRobotics. (NCT02505919).