Optilume drug-coated balloon for anterior urethral stricture: 2-year results of the ROBUST III trial.

Abstract

The aim of this study is to report the updated 2-year results of the intervention arm of the ROBUST III randomized trial evaluating the safety and efficacy of the Optilume drug-coated balloon (DCB) versus standard endoscopic management of recurrent male anterior urethral stricture. Eligible patients included men with recurrent anterior urethral stricture ≤3cm in length and ≤12Fr in diameter, International Prostate Symptom Score (IPSS) ≥11 and peak flow rate (Qmax) <15 mL/s. Patients were randomized to treatment with the Optilume DCB or standard-of-care endoscopic management. Primary efficacy endpoints measured at 2years included freedom from re-intervention and changes in IPSS, Qmax and post-void residual (PVR). Secondary endpoint was impact on sexual function using the International Index of Erectile Function (IIEF). Primary safety endpoint was freedom from serious procedure- or device-related adverse events (AEs). A total of 127 patients enrolled at 22 sites in the United States and Canada (48 randomized to standard-of-care dilation and 79 to DCB dilation). Seventy-five patients in the DCB arm entered the open-label phase after 6 months. Participants averaged 3.2 prior endoscopic interventions (range 2-10); most (89.9%) had bulbar strictures with an average stricture length of 1.63 cm (SD 0.76). Significant improvements in IPSS, average Qmax and PVR were maintained at 2years. Freedom from repeat intervention was significantly higher in the Optilume DCB arm at 2years versus the Control arm at 1year (77.8% vs. 23.6%, p < 0.001). During the follow-up period, there were 15 treatment failures and two non-study-related deaths. Treatment-related AEs were rare and generally self-limited (haematuria, dysuria and urinary tract infection). The Optilume DCB shows sustained improvement in both objective and subjective voiding parameters at 2-year follow-up. Optilume appears to provide a safe and effective endoscopic treatment alternative for short recurrent anterior urethral strictures among men who wish to avoid or delay formal urethroplasty.