Standard of care treatment of stricture of the anterior urethra using the Optilume Drug Coated Balloon.

The responder rate is defined as the proportion of subjects experiencing a ≥30% improvement in International Prostate Symptom Score (IPSS) without repeat intervention for the study stricture. The responder rate at 12 months post-treatment will be compared against a performance goal of 60%.

The International Prostate Symptom Score (IPSS) (score 0-7 = mild; score 8-19 = mediate; score 20-35 = severe complaints) was chosen as the primary patient-reported outcome measure (PROM) for follow-up due to its inclusion in the EAU guidelines, its long history of use, its inclusion as the primary PROM in the ROBUST clinical program, and the availability of literature describing clinically meaningful improvement in the setting of bladder outlet obstruction.

The primary safety endpoint is defined as the proportion of subjects experiencing a treatment related Serious Adverse Event (SAE) through 3 months post-treatment. The primary safety endpoint will be analyzed with descriptive statistics and nominal 95% confidence interval.

No single event type is expected to happen with greater frequency than other endoscopic therapies, therefore any event that meets the definition of an SAE and is considered treatment related will be included in the endpoint.

The proportion of subjects experiencing treatment related adverse events will be summarized by event type and severity as graded by the Clavien-Dindo scale. 'Treatment Related' consists of events deemed Possible, Probable, or Definite in relation to the Optilume® DCB or the dilation procedure.