OnabotulinumtoxinA (Botox®): A Review of its Use in the Treatment of Urinary Incontinence in Patients with Multiple Sclerosis or Subcervical Spinal Cord Injury

Abstract

OnabotulinumtoxinA (BOTOX(®)) is a type A neurotoxin derived from Clostridium botulinum bacteria that is approved as treatment for urinary incontinence (UI) in patients with neurogenic detrusor overactivity resulting from multiple sclerosis (MS) or subcervical spinal cord injury (SCI) who are not adequately treated by antimuscarinics. This article reviews the pharmacology of intradetrusor onabotulinumtoxinA in this indication. The presumed mode of action of onabotulinumtoxinA in bladder disorders is by interfering with efferent innervation of the detrusor muscle and afferent pathways involved in the micturition reflex. In phase III trials in adult patients with MS or SCI with UI who were not adequately treated with antimuscarinics, intradetrusor onabotulinumtoxinA 200 U produced significantly greater mean changes (reductions) from baseline in UI episodes/week at week 6 than placebo (primary endpoint). Similar significant benefits of intradetrusor onabotulinumtoxinA 200 U over placebo were observed on other UI, urodynamic, health-related quality of life and treatment satisfaction endpoints. Intradetrusor onabotulinumtoxinA 200 U was generally well tolerated, with the most frequent adverse events being urinary tract infections and urinary retention. Few patients discontinued treatment because of adverse events. Based on interim analyses of an extension study of the phase III trials, repeat injections of onabotulinumtoxinA 200 U were similarly efficacious and well tolerated. Intradetrusor onabotulinumtoxinA represents a clinically important advance in the therapy of UI in patients with MS or SCI who have not responded to antimuscarinics or who are unable to tolerate antimuscarinics.

Voiding Dysfunction in Multiple Sclerosis

“…Approved by the U.S. Food and Drug Administration for the treatment of neurogenic bladder dysfunction in 2011, it is injected into the bladder using a cystoscope. 39 The effect lasts 6 to 12 months, at which point another injection is required. The treatment carries a risk of urinary retention, which would require short-term CIC.…”

Efficacy of mirabegron for overactive bladder with human T cell lymphotropic virus‐1 associated myelopathy

“…Carneiro et al reported the efficacy of botulinum toxin type A for HAM/TSP‐associated OAB refractory to conventional drug in 3 patients. Botulinum toxin type A, a neuromuscular blocking agent, has been used to treat neurogenic OAB following detrusor overactivity in patients with multiple sclerosis and spinal cord injury . Botulinum toxin type A is usually injected intravesically and is an invasive therapy.…”

Long term sustained therapeutic effects of percutaneous posterior tibial nerve stimulation treatment of neurogenic overactive bladder in multiple sclerosis patients: 12‐months results

“…Botulinum toxin is an invasive technique which has similar efficacy to sacral neuromodulation (SNM) in NOAB; improvement rates of 63.5% for Botox and 58.5% for SNM have been reported . Moreover in studies which evaluated the effect of botulinum toxin in NOAB, it has been suggested that it is a clinically important advance in the therapy of urinary incontinence in patients with MS or spinal cord injury (SCI) who have not responded to antimuscarinics or who are unable to tolerate antimuscarinics . In another study, it was reported that botulinum toxin treatment has beneficial effects not only on urinary symptoms but also on QoL, in patients with SCI and MS .…”