WATER: A Double-Blind, Randomized, Controlled Trial of Aquablation vs Transurethral Resection of the Prostate in Benign Prostatic Hyperplasia

We compared the safety and efficacy of aquablation and transurethral prostate resection for the treatment of lower urinary tract symptoms related to benign prostatic hyperplasia.

In a double-blind, multicenter, prospective, randomized, controlled trial 181 patients with moderate to severe lower urinary tract symptoms related to benign prostatic hyperplasia underwent transurethral prostate resection or aquablation. The primary efficacy end point was the reduction in I-PSS (International Prostate Symptom Score) at 6 months. The primary safety end point was the development of Clavien-Dindo persistent grade 1, or 2 or higher operative complications.

Mean total operative time was similar for aquablation and transurethral prostate resection (33 vs 36 minutes, p = 0.2752) but resection time was lower for aquablation (4 vs 27 minutes, p <0.0001). At month 6 patients treated with aquablation and transurethral prostate resection experienced large I-PSS improvements. The prespecified study noninferiority hypothesis was satisfied (p <0.0001). Of the patients who underwent aquablation and transurethral prostate resection 26% and 42%, respectively, experienced a primary safety end point, which met the study primary noninferiority safety hypothesis and subsequently demonstrated superiority (p = 0.0149). Among sexually active men the rate of anejaculation was lower in those treated with aquablation (10% vs 36%, p = 0.0003).

Surgical prostate resection using aquablation showed noninferior symptom relief compared to transurethral prostate resection but with a lower risk of sexual dysfunction. Larger prostates (50 to 80 ml) demonstrated a more pronounced superior safety and efficacy benefit. Longer term followup would help assess the clinical value of aquablation.

The Journal of urology. 2018 Jan 31 [Epub ahead of print]

Peter Gilling, Neil Barber, Mohamed Bidair, Paul Anderson, Mark Sutton, Tev Aho, Eugene Kramolowsky, Andrew Thomas, Barrett Cowan, Ronald P Kaufman, Andrew Trainer, Andrew Arther, Gopal Badlani, Mark Plante, Mihir Desai, Leo Doumanian, Alexis E Te, Mark DeGuenther, Claus Roehrborn

Tauranga Urology Research, Tauranga, New Zealand., Frimley Park Hospital, Frimley Health Foundation Trust, Surrey, Wales, United Kingdom., San Diego Clinical Trials, San Diego, California., Royal Melbourne Hospital, Melbourne, Australia., Houston Metro Urology, Houston, Texas., Addenbrooke's Hospital, Cambridge University Hospitals, Cambridge, Wales, United Kingdom., Virginia Urology, Richmond, Virginia., Princess of Wales Hospital, Bridgend, Wales, United Kingdom., Urology Associates, P.C., Englewood, Colorado., Albany Medical College, Albany, New York., Adult Pediatric Urology and Urogynecology, P.C., Omaha, Nebraska., Wake Forest School of Medicine, Winston-Salem, North Carolina., University of Vermont Medical Center, Burlington, Vermont., Institute of Urology, University of Southern California, Los Angeles, California., Weill Cornell Medical College, New York, New York., Urology Centers of Alabama, Birmingham, Alabama., Department of Urology, Southwestern Medical Center, University of Texas Southwestern, Dallas, Texas. Electronic address: .