We evaluated the efficacy/safety of onabotulinumtoxin A 100U versus placebo for treatment of urinary incontinence (UI) due to neurogenic detrusor overactivity (NDO) in non-catheterising multiple sclerosis (MS) patients inadequately managed by≥1 anticholinergic.

A multicentre, double-blind study randomised patients 1:1 to onabotulinumtoxin A 100U (n=66) or placebo (n=78). Assessments (week 6 primary endpoint) included change from baseline in UI episodes (UIE)/day (primary endpoint), maximum cystometric capacity (MCC), maximum detrusor pressure (MDP) during first involuntary detrusor contraction (IDC), incontinence-quality of life (I-QOL) total summary score, and proportions of patients achieving 100% UIE reduction. Median duration of effect (DOE), initiation of clean intermittent catheterisation (CIC), and adverse events (AEs) were also assessed.

Baseline characteristics were similar between groups. The mean baseline EDSS score was 4.7. Onabotulinumtoxin A 100U significantly improved UIE (–3.3 vs–1.1; P<.001), MCC (+127.2 vs–1.8mL; P<.001), and MDP during first IDC (–19.6 vs 3.7cm H₂O; P<.01) versus placebo. Significantly greater proportions of onabotulinumtoxin A treated patients achieved 100% UIE reduction versus placebo (53.0% vs 10.3%; P<.001). I-QOL improvements were significantly greater with onabotulinumtoxin A versus placebo (40.4 vs 9.9; P<.001). DOE was 11.9 versus 2.9 months, respectively (P<.001). Discontinuations due to AEs/lack of efficacy were low (1.4%/2.1%). Most common AEs were UTI, elevated residual urine volume, and urinary retention. CIC rates were 15.2% for onabotulinumtoxinA 100U and 2.6% for placebo. Previous studies demonstrated CIC rates of 31.4% for onabotulinumtoxinA 200U and 4.5% for placebo in MS patients not catheterising at baseline1.

In non-catheterising MS patients with UI, onabotulinumtoxin A 100U resulted in significant and clinically-meaningful improvements in UI, MCC, MDP at first IDC, and QOL versus placebo and was well-tolerated.