The Optilume Urethral Drug Coated Balloon for Recurrent Anterior Urethral Strictures: 3-year Results from the ROBUST I Study

Chee J1, Elliott S2, Virasoro R3, DeLong J3, Estrella R4, Pichardo M5, Rodriguez R6, Espino G7

Research Type

Clinical

Abstract Category

Urethra Male / Female

Abstract 1
Live Urology 1 - Surgical Insights
Scientific Podium Session 1
Thursday 14th October 2021
08:00 - 08:10
Live Room 1
New Devices Clinical Trial Prospective Study
1. MURAC Health, 2. University of Minnesota, 3. Eastern Virginia Medical School, 4. Clinica Union Medica, Santiago de los Caballeros, 5. URUS, Santo Domingo, 6. Urology Royal Center Panamá City, 7. Centro Especializado San Fernando, Panamá City
Presenter
J

Justin Chee

Links

Abstract

Hypothesis / aims of study
Mechanical dilation and direct visualization internal urethrotomy (DVIU) are the most widely utilized treatments for urethral stricture disease, but recurrence rates are high after re-treatment. The Optilume® Urethral Drug Coated Balloon (DCB) is a urethral dilation balloon with a proprietary paclitaxel coating that combines mechanical dilation of the stricture for immediate symptomatic relief with local drug delivery to maintain urethral patency. The ROBUST I study investigates the safety and efficacy of the Optilume DCB for the treatment of recurrent anterior urethral strictures.
Study design, materials and methods
ROBUST I was a prospective, single-arm, open-label study conducted under a common protocol in Latin America. Eligible participants were adult men with a single anterior urethral stricture <12F and ≤2cm in length with 1-3 prior endoscopic treatments, International Prostate Symptom Score (IPSS) ≥13, and maximum flow rate (Qmax) <10 mL/sec.  After treatment with the Optilume DCB, subjects were followed at 5 days (Foley removal), 14 days, 30 days, 3 months, 6 months, and annually through 3 years. The primary safety endpoint was the rate of treatment-related serious urinary adverse events. The efficacy endpoint was the proportion of subjects with ≥ 50% improvement in IPSS at 3 years. Subjects receiving secondary treatment were treated as failures for this endpoint. Secondary outcomes included quality of life (QOL), freedom from repeat intervention, erectile function, Qmax, and post-void residual (PVR) urine volume.
Results
A total of 53 subjects were enrolled and treated with the Optilume DCB at 4 centers. Subjects had bulbar strictures, with an average stricture length of 0.9 cm, and 1.7 prior dilations; 43% of men had undergone ≥2 previous dilations. Of the 53 treated subjects, 43 were evaluable at the 3-year follow-up for the efficacy endpoint. There were no serious adverse events related to treatment at 3 years. Success at 3 years was achieved in 67% (29/43) which is consistent with 2-year results (68%, 32/47).  Subjects treated with the 30F diameter Optilume DCB had significantly higher responder rate at 3 years compared to subjects treated with the 24F diameter (83% vs 50%).  IPSS improved from a mean of 25.2 at baseline to 5.5 at 3 years (unpaired t-test, p<0.001). Freedom from repeat intervention of the study stricture at 1, 2, and 3 years was 83% (40/48), 81% (38/47), and 77% (33/43), respectively. From baseline to 3 years, IPSS QOL improved from 4.9 to 0.7, Qmax improved from 5.0 mL/sec to 15.1 mL/sec, and PVR urine volume improved from 141.4 mL to 50.2 mL (unpaired t-test, p<0.001 for all). The International Index of Erectile Function (IIEF) overall satisfaction score improved from 6.5 at baseline to 8.2 at 3 years.
Interpretation of results
Significant improvements from baseline in symptom severity, quality of life, and voiding function were observed at 3 years after treatment with the Optilume DCB. Functional success at 3 years was consistent with 2-year results. There was no negative impact of the treatment on erectile function. Follow-up is planned through 5 years to further define the durability of the treatment.
Concluding message
Subjects with recurrent bulbar strictures treated with the Optilume paclitaxel-coated balloon exhibited significant improvement in symptomatic and functional outcomes through 3 years post-treatment. Long-term follow-up will continue through 5 years in the ROBUST I study and a randomized trial is ongoing.
Disclosures
Funding ROBUST I was sponsored and funded by Urotronic Inc Clinical Trial Yes Registration Number NCT03499964 RCT No Subjects Human Ethics Committee Western Institutional Review Board Helsinki Yes Informed Consent Yes
31/05/2022 15:34:22