Laborie Medical Technologies has announced promising long-term outcomes for its Optilume® Drug-Coated Balloon (DCB) in treating recurrent urethral strictures, according to three-year data from the ROBUST III randomized controlled trial published in the Journal of Endourology.
The study demonstrated that 71.9% of patients treated with Optilume remained free from repeat intervention at the three-year mark, maintaining consistency with previous two-year results and showing a dramatic improvement compared to the control group's 23.6% rate at one year. This represents a threefold increase in durability compared to standard endoscopic management techniques.
"Minimally invasive, yet durable treatments for stricture disease have been something we have been waiting for in the stricture space," said Dr. Karl Coutinho, M.D. "Optilume gives us an endoscopic option that provides real staying power, especially for patients unable to have urethroplasty or looking to avoid more invasive procedures."
Sustained Symptom Improvement and Functional Outcomes
The ROBUST III trial enrolled 127 male patients with urethral strictures, randomizing 79 to receive the Optilume DCB and 48 to the control arm. At the three-year follow-up, 45 patients remained in the study.
Patients treated with Optilume experienced sustained symptomatic improvement. The International Prostate Symptom Score (IPSS) improved from a baseline average of 22.0 to 11.6 at three years, with 48% of patients achieving at least a 30% IPSS improvement without requiring repeat intervention.
Objective voiding parameters also showed durable benefits:
- Peak urinary flow rate (Qmax) improved from 7.6 mL/s at baseline to 15.5 mL/s at one year, maintaining at 10.6 mL/s by year three
- Postvoid residual (PVR) volumes declined from 101.6 mL at baseline to 42.2 mL at three years
These results align with recently published five-year data from the ROBUST I trial, which showed 58% of patients achieving functional success (defined as at least 50% improvement in IPSS) and an estimated 71.7% freedom from repeat intervention at the five-year mark.
Innovative Dual-Action Mechanism
The Optilume DCB represents a significant advancement in urethral stricture management by combining mechanical dilation with localized delivery of paclitaxel, an antiproliferative drug that inhibits scar tissue regrowth. This dual mechanism provides both immediate symptom relief through dilation and long-term protection against recurrence through drug action.
Notably, the study demonstrated consistent efficacy across challenging patient subgroups, including those with longer strictures and patients who had undergone five or more prior dilations—populations traditionally prone to early recurrence after conventional treatments.
Safety Profile and Control Group Crossover
The treatment maintained a favorable safety profile throughout the three-year follow-up period. The most common treatment-related adverse events included post-procedural hematuria (11.4%), dysuria (7.6%), and urinary tract infection (6.3%). Importantly, no late-onset serious treatment-related adverse events were observed during the study's follow-up period.
Of the 48 participants in the control arm, 32 experienced stricture recurrence and opted to cross over to receive Optilume treatment. These crossover patients also saw marked improvement, with more than 75% remaining free from reintervention one year post-crossover.
Clinical Implications
Urethral strictures—narrowings of the urethra caused by scar tissue—affect approximately 0.6% of the male population and can significantly impact quality of life through symptoms including weak urine stream, incomplete emptying, and urinary tract infections. Traditional management options include repeated endoscopic dilations or incisions, which have high recurrence rates, or more invasive urethroplasty surgery.
The FDA approved Optilume in December 2021 based on data from the ROBUST I and ROBUST III clinical trials. The latest three-year data further establishes Optilume as a disruptive innovation in stricture care, offering a middle-ground option between repeated endoscopic procedures with high recurrence rates and more invasive surgical approaches.
For patients with recurrent urethral strictures, particularly those seeking to avoid surgery or who are poor surgical candidates, these results suggest Optilume provides a durable, minimally invasive alternative with sustained benefits extending to at least three years post-treatment.
