Management of Overactive Bladder After Radical Prostatectomy: Safety and Clinical Pathways Following Intradetrusor OnabotulinumtoxinA

INTRODUCTION: Men with overactive bladder (OAB) following radical prostatectomy may undergo intradetrusor onabotulinumtoxinA (onabotA), including in the setting of artificial urinary sphincter (AUS) or male sling placement. However, data regarding urinary retention and de novo clean intermittent catheterization (CIC), as well as longitudinal treatment patterns, remain limited in this population. We evaluated the safety and treatment patterns of onabotA in men with OAB following radical prostatectomy, with particular attention to patients undergoing continence surgery. METHODS: We performed a retrospective single-center cohort study of adult men with a history of radical prostatectomy undergoing intradetrusor onabotA between 2018 and 2025. Patients were categorized as: (1) onabotA only after radical prostatectomy or (2) an AUS/sling group comprising patients who underwent continence surgery before or during onabotA treatment. The primary outcome was de novo CIC following treatment. Secondary outcomes included elevated postvoid residual (PVR), treatment characteristics, dose escalation, treatment persistence, and descriptive analyses of clinical pathways and urodynamic findings among patients undergoing prior continence surgery. Kaplan-Meier methods were used to evaluate treatment persistence among patients receiving at least two injections. RESULTS: Thirty-two men underwent intradetrusor onabotA after radical prostatectomy. Fourteen comprised the onabotA-only group and 18 the AUS/sling group, including 17 who underwent continence surgery before onabotA and one who underwent male sling placement after treatment with onabotA. Median follow-up after first onabotA injection was 1.75 years (IQR 0.57-2.91). Twenty-two patients (68.8%) received at least two injections, including 50.0% (7/14) and 83.3% (15/18) in the respective groups (p = 0.062). No patient developed de novo CIC following treatment. Elevated PVR (≥ 200 mL) occurred in 9.4% (3/32) of patients, all in the onabotA-only group. Among patients receiving repeat treatment, dose escalation to 200-300 units occurred in 50.0% (11/22). Treatment persistence did not differ between groups (log-rank p = 0.851). CONCLUSION: Intradetrusor onabotA demonstrated a favorable safety profile among men with OAB following radical prostatectomy, including those undergoing AUS or male sling placement, with no patients requiring de novo CIC. These findings support consideration of onabotA in appropriately selected patients as part of the individualized management of persistent bladder dysfunction after prostate cancer treatment.