Sex-specific efficacy of mirabegron for overactive bladder (OAB) symptoms: individual patient data meta-analyses

Overactive bladder syndrome is a common condition including a number of highly bothersome symptoms such as rushing to the toilet, leaking urine before reaching a toilet, and emptying the bladder too often both during the day and night. This problem affects hundreds of million men and women worldwide, and gets more common with age.

Doctors try to treat overactive bladder with different drugs. Most often drugs to relax the bladder, called ‘anti-muscarinic’ drugs, are used. Unfortunately, the effect of these drugs is disappointing for many patients. Up to eighty percent of patients stop these drugs within a few months, either because of severe side-effects or simply because they do not work well.

Recently, a new drug has become available for overactive bladder, called mirabegron. Studies demonstrate clearly that mirabegron is slightly more effective than a placebo (a fake drug / sugar pills), but it is unclear whether the drug works better for men or women. Such a difference is important because overactive bladder has different causes in men and women, with many men suffering symptoms of overactive bladder due to swelling of the prostate gland.

We therefore aim to study the difference in effect between men and women of mirabegron. We will combine all available data from different studies, without needing to perform a new trial in patients. For men and women, we will compare the change in symptoms at 6 weeks, 3 months, and one year, looking both at studies where mirabegron was tested as an alternative to placebo, and studies where it was tested against another drug.

The results of our analyses may enable physicians to target the use of mirabegron better. We will inform physicians about the results from our study with publication in specialist journals and presentations at scientific meetings. We will inform patients, patient organizations and policy makers by publicizing our results in the lay press as well.