Mirabegron for the treatment of overactive bladder: a prespecified pooled efficacy analysis and pooled safety analysis of three randomised, double-blind, placebo-controlled, phase III studies

Introduction To examine pooled efficacy data from three, large phase III studies comparing mirabegron (50 and 100mg) with placebo, and pooled safety data including additional mirabegron 25mg and tolterodine extended release (ER) 4mg results. Methods This prespecified pooled analysis of three randomised, double-blind, placebo-controlled, 12-week studies, evaluated efficacy and safety of once-daily mirabegron 25mg (safety analysis), 50 or 100mg (efficacy and safety analyses) and tolterodine ER 4mg (safety analysis) for the treatment of symptoms of overactive bladder (OAB). Co-primary efficacy measures were change from baseline to Final Visit in the mean number of incontinence episodes/24h and mean number of micturitions/24h. Key secondary efficacy end-points included mean number of urgency episodes/24h and mean volume voided/micturitions, while other end-points included patient-reported outcomes according to the Treatment Satisfaction-Visual Analogue Scale (TS-VAS) and responder analyses [dry rate (posttreatment), 50% reduction in incontinence episodes/24h, 8 micturitions/24h (post hoc analysis)]. The safety analysis included adverse event (AE) reporting, laboratory assessments, ECG, postvoid residual volume and vital signs (blood pressure, pulse rate). Results Mirabegron (50 and 100mg once daily) demonstrated statistically significant improvements compared with placebo for the co-primary end-points, key secondary efficacy variables, TS-VAS and responder analyses (all comparisons p