FDA approves Botox to treat overactive bladder

FDA expanded the approved use onabotulinumtoxinA (Botox, Allergan) to treat adults with overactive bladder (OAB) who cannot use or do not adequately respond to anticholinergics.

OAB is a condition in which the bladder squeezes too often or squeezes without warning. Symptoms include leaking urine (urinary incontinence), feeling the sudden and urgent need to urinate, and frequent urination. OAB affects an estimated 33 million men and women in the United States.

When Botox is injected into the bladder muscle, it causes the bladder to relax, increasing the bladder’s storage capacity and reducing episodes of urinary incontinence. Injecting the bladder with Botox is performed using cystoscopy.

“Clinical studies have demonstrated Botox’s ability to significantly reduce the frequency of urinary incontinence,” Hylton V. Joffe, MD, director of the Division of Reproductive and Urologic Products in FDA’s Center for Drug Evaluation and Research, said in a press release.

In 2 double-blind, randomized, multicenter, placebo-controlled 24-week clinical trials among 1,105 adults with overactive bladder who had not been adequately managed with anticholinergic treatments, Botox reduced daily urinary incontinence (leakage) episodes as compared to placebo by 50% or more by week 12 (reduction of 2.5 episodes from baseline of 5.5 episodes in 1 study and reduction of 3 episodes from baseline of 5.5 episodes in the second study for those treated with Botox versus a reduction of 0.9 episodes from a baseline of 5.1 episodes in 1 study and a reduction of 1.1 episodes from a baseline of 5.7 episodes in the second study for those treated with placebo).

Treatment with Botox can be repeated when the benefits from the previous treatment have decreased, but there should be at least 12 weeks between treatments.

Common side effects reported during clinical trials included urinary tract infections, painful urination, and incomplete emptying of the bladder (urinary retention). Patients who develop urinary retention may need to use a catheter until the urinary retention resolves. Patients being treated for OAB with Botox should not have a urinary tract infection and should take antibiotics before, during, and for a few days after Botox treatment to lower the chance of developing an infection from the procedure.