The WATER III clinical trial has demonstrated that Aquablation therapy delivers symptom relief comparable to laser enucleation for benign prostatic hyperplasia (BPH) while significantly preserving sexual function and continence, according to data presented at the 40th Annual European Association of Urology Congress in Madrid, Spain.
The international, prospective, multicenter study compared Aquablation therapy to transurethral laser enucleation of large prostates (LEP) in 186 men with prostate sizes ranging from 80-180mL. The trial, conducted between December 2020 and September 2024, reported its three-month primary safety and efficacy endpoints, with plans to follow patients for up to five years.
Comparable Symptom Improvement with Better Quality of Life Outcomes
The study's primary endpoint showed that Aquablation demonstrated non-inferiority to LEP regarding mean change in International Prostate Symptom Score (IPSS). The change in IPSS from baseline to 3 months was 12.9 in the Aquablation arm versus 13.1 in the LEP arm (mean delta, 0.86; 95% CI, -1.6 to 3.2; P = .745).
Most notably, patients who underwent Aquablation therapy experienced significantly lower rates of ejaculatory dysfunction (14.8% vs. 77.1%, P < .0001) and stress incontinence (0% vs. 9.1%, P = .0690) compared to those who received laser enucleation.
"The WATER III results are impressive, demonstrating that Aquablation therapy can achieve outcomes comparable to laser enucleation," said Dr. Naeem Bhojani from the University of Montreal. "The consistent efficacy coupled with the significantly lower rates of ejaculatory dysfunction and stress incontinence represents a meaningful advancement for patients seeking treatment for BPH."
Differences in Urinary Flow Metrics
While Aquablation showed advantages in preserving sexual function and continence, the study revealed that urinary flow rate improvement from baseline to 3 months was greater in the LEP arm (P < .0001). Patients in the LEP arm also experienced a greater reduction in post-void residual (P = .2956).
Importantly, the procedural transfusion rate in the Aquablation therapy arm was 0%, demonstrating that modern Aquablation techniques are both safe and highly reproducible in managing bleeding risk. Overall bleeding risk was comparable between both treatment arms.
Technology Behind Aquablation
Aquablation therapy, developed by PROCEPT BioRobotics Corporation (Nasdaq: PRCT), is the first and only ultrasound-guided, robotic-assisted, heat-free waterjet for BPH treatment. The system provides surgeons with a multi-dimensional view of the prostate through real-time ultrasound imaging, enabling personalized treatment planning tailored to each patient's unique anatomy.
The technology allows surgeons to specify which areas of the prostate to remove while preserving the anatomy that controls erectile function, ejaculatory function, and continence. Once the treatment plan is mapped, the robotic-assisted execution enables prostate tissue to be removed in a precise, targeted, and controlled fashion.
Building on Previous Clinical Evidence
The WATER III results build upon PROCEPT BioRobotics' previous randomized clinical trials, including the WATER study (comparing Aquablation therapy to TURP in 30-80 mL prostates) with five-year results and WATER II (evaluating Aquablation therapy in large prostates 80-150 mL) also with five-year results.
"WATER III represents a significant milestone in our mission to establish Aquablation therapy as the standard of care for patients suffering with BPH," said Reza Zadno, CEO of PROCEPT BioRobotics. "What makes these results particularly meaningful is Aquablation therapy's ability to deliver effective symptom relief while preserving critical quality of life factors—specifically sexual function and continence."
Clinical Implications for BPH Treatment
BPH affects approximately 40 million men in the United States alone. The condition, characterized by an enlarged prostate gland, can cause significant urinary symptoms that impact quality of life. Traditional surgical approaches have often required patients to choose between effective symptom relief and preservation of sexual function.
The WATER III trial suggests that Aquablation may offer a solution to this dilemma, providing effective symptom relief while better preserving sexual function compared to laser enucleation, which has been considered a gold standard for treating large prostates.
The growing body of clinical evidence, now including multiple randomized clinical studies, demonstrates that Aquablation therapy is a globally reproducible procedure with the potential to become the BPH standard of care across all prostate sizes.
As the five-year follow-up data from WATER III becomes available, clinicians will gain further insights into the long-term durability and safety profile of Aquablation compared to laser enucleation, potentially reshaping treatment algorithms for men with BPH.
