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.
Keywords: multiple sclerosis; neurogenic detrusor overactivity; onabotulinumtoxinA; spinal cord injury; urinary incontinence.
© 2013 Wiley Periodicals, Inc.