Long-Term Efficacy and Safety of OnabotulinumtoxinA in Patients with Neurogenic Detrusor Overactivity Who Completed 4 Years of Treatment

Purpose: We assessed the year-to-year consistency of outcomes in patients with urinary incontinence due to neurogenic detrusor overactivity who completed 4 years of onabotulinumtoxinA treatment.

Materials and methods: Eligible patients who completed a 52-week phase 3 trial of onabotulinumtoxinA for urinary incontinence could enter a 3-year open label extension study of onabotulinumtoxinA 200 or 300 U administered as needed for symptom control. This analysis focused on 227 patients who completed the 4-year study. Outcomes assessed by year of treatment included mean treatments per year, mean change from baseline at week 6 in urinary incontinence episodes per day and the I-QOL (Incontinence Quality of Life) total summary score, the proportion of patients with 50% or greater and 100% reductions in urinary incontinence episodes per day, duration of effect and adverse events.

Results: Patients reported 4.3 urinary incontinence episodes per day at baseline and received 1.4 to 1.5 onabotulinumtoxinA treatments per year. The decrease in urinary incontinence following onabotulinumtoxinA consistently ranged from -3.4 to -3.9 episodes per day across 4 years. A high proportion of patients achieved 50% or greater and 100% urinary incontinence reductions in each year (range 86.6% to 94.1% and 43.6% to 57.4%, respectively). Consistent and clinically relevant improvements in I-QOL scores were observed in each treatment year. The overall median duration of effect of onabotulinumtoxinA was 9.0 months or greater (range 3.0 to 49.2) and 26.0% or more of patients experienced a duration of effect of 12 months or greater. The most common adverse event was urinary tract infection with no increased incidence with time.

Conclusions: Patients with neurogenic detrusor overactivity who completed 4 years of onabotulinumtoxinA treatment experienced a consistent duration of treatment effect and year-to-year improvements in urinary incontinence and quality of life with no new safety signals.