Noncatherizing patients with multiple sclerosis (MS) treated with low-dose onabotulinumtoxinA (100 U) exhibited significantly improved urinary incontinence and quality of life, with lower frequencies of clean intermittent catheterization, according to a study published in Neurology.
To evaluate the safety and efficacy of 100 U onabotulinumtoxinA for noncatherizing patients with urinary incontinence due to neurogenic detrusor overactivity from multiple sclerosis, investigators conducted a double-blind, randomized, placebo-controlled, phase 3 study at 58 North American and European sites between July 2012 and March 2015. Patients were assigned to 1 of 2 strata based on baseline parameters of multiple sclerosis duration, age, anticholinergic use, and episodes of urinary incontinence per day, then randomly assigned within those strata to onabotulinumtoxinA 100 U (n=66) or placebo (n=78). To ensure double-blinding, onabotulinumtoxinA and placebo were packaged and labeled identically.
For up to 52 weeks, 144 patients were assessed during clinic visits at weeks 2, 6, 12, 24, and 52. Prior to each visit, patients recorded clean intermittent catherization events, volume per void, and urinary symptoms in 3-day bladder diaries. Urodynamic assessments were conducted according to the standards of the International Continence Society. The Incontinence-Quality of Life questionnaire (I-QOL) was used at baseline, then at weeks 6 and 12.
Urinary incontinence was significantly reduced in onabotulinumtoxinA arm compared with placebo at week 6. The onabotulinumtoxinA arm showed significantly greater frequencies of 100% urinary incontinence reduction compared with placebo (53.0% vs 10.3%, P <.001) and significant urodynamics improvements. The onabotulinumtoxinA arm also showed significantly greater improvements in I-QOL scores than placebo (40.4 vs 9.9, P <.001), with approximately 3 times (+11 points) the minimally important difference. Rates of clean intermittent catheterization for onabotulinumtoxinA vs placebo were 15.2% and 2.6%.
The most common adverse events were urinary tract infection, urinary retention, bacteriuria, residual urine volume, and dysuria.
Study investigators conclude that, “this trial demonstrates that in noncatheterizing patients with MS and [neurogenic detrusor overactivity], treatment with onabotulinumtoxinA 100 U results in significant and clinically relevant improvements in UI and other urinary symptoms, urodynamics, and QOL with lower [clean intermittent catheterization] and [urinary tract infection] rates than previously reported with onabotulinumtoxinA 200 U.”
Tullman M, Chartier-Kastler E, Kohan A, et al. Low-dose onabotulinumtoxinA improves urinary symptoms in noncatheterizing patients with MS [published online July 20, 2018]. Neurology. doi: 10.1212/WNL.0000000000005991