The FDA has approved onabotulinumtoxinA (Botox) as a treatment for overactive bladder (OAB) in adults who are inadequately managed with anticholinergic medications.
The approval was based on two 24-week double-blind, randomized, placebo-controlled trials in which onabotulinumtoxinA reduced daily urinary incontinence episodes by 50% or more by week 12 compared with placebo. In the two trials, complete continence was achieved in 22.9% and 31.4% of patients treated with onabotulinumtoxinA compared with 6.5% and 10.3% of placebo recipients at week 12.
The two trials included 1,105 adult patients whose OAB symptoms had not been adequately managed with anticholinergics, either because of lack of efficacy or intolerance to the drugs. The most frequently reported adverse reactions within 12 weeks of receiving onabotulinumtoxinA included urinary tract infections (18% vs. 6% with placebo), dysuria (9% vs. 7%), and urinary retention (6.5% vs. 0.4%).
The median duration of efficacy for onabotulinumtoxinA at reducing urinary leakage and other OAB symptoms in the two studies was 135-168 days compared with 88-92 days with placebo based on qualification for retreatment.