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Updated: May 14, 2026

Detrusor Underactivity Model in Rats by Conus Medullaris Transection
Published on: August 28, 2020
OnabotulinumtoxinA improves urodynamic outcomes in patients with neurogenic detrusor overactivity
Eric Rovner1, Roger Dmochowski, Christopher Chapple
1Department of Urology, Medical University of South Carolina, Charleston, South Carolina.
Aims:
To evaluate the effect of onabotulinumtoxinA on urodynamic outcomes in patients with urinary incontinence (UI) due to neurogenic detrusor overactivity (NDO).
Methods:
Results from two pivotal Phase III trials (n = 691) were pooled. MS or SCI patients with NDO, received intradetrusor onabotulinumtoxinA 200 U (n = 227), 300 U (n = 223), or placebo (n = 241). Change from baseline in UI episodes/week (Week 6), maximum cystometric capacity (MCC), maximum detrusor pressure at first involuntary detrusor contraction (IDC) (PdetmaxIDC), volume at first IDC (VpmaxIDC), and detrusor compliance (DC) were measured.
Results:
OnabotulinumtoxinA significantly increased MCC overall (+153.6 ml with 200 U vs. +11.9 ml with placebo). Over 60% of onabotulinumtoxinA-treated patients had no IDC at Week 6; in patients with an IDC at Week 6, VpmaxIDC improved (+183.4 ml with 200 U vs. +17.5 ml with placebo), and PdetmaxIDC decreased (-32.4 cmH2O with 200 U vs. +1.1 cmH2O with placebo). OnabotulinumtoxinA-treated patients had a significant increase in DC (+59.8 ml/cmH2O with 200 U vs. -5.2 with placebo). Urodynamic improvements were comparable in patients regardless of baseline DC and corresponded with significant reductions in UI episodes/week for both onabotulinumtoxinA doses versus placebo, with no clinically relevant differences between 200 and 300 U groups. Most common adverse event was urinary tract infection (UTI); complicated UTIs were low across all treatment groups. In patients not catheterizing at baseline, a dose-dependent increase in post-void residual urine was observed at Week 2 following onabotulinumtoxinA treatment.
Conclusions:
OnabotulinumtoxinA significantly improved urodynamic outcomes in NDO patients, even in those with low baseline DC, and corresponded with improvements in UI episodes. Both doses of onabotulinumtoxinA were well tolerated.
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