Mirabegron: A Review of Its Use in Patients with Overactive Bladder Syndrome

Mirabegron (YM178, Myrbetriq (TM), Betanis(A (R)), Betmiga (TM)) is a beta(3)-adrenergic receptor agonist approved in several countries for the symptomatic treatment of adults with overactive bladder syndrome. In three 12-week, randomized, double-blind, placebo-controlled, multinational trials in patients with overactive bladder syndrome, oral mirabegron 25 or 50 mg once daily significantly reduced the adjusted mean number of incontinence episodes per 24 h (in patients with incontinence at baseline) and the adjusted mean number of micturition episodes per 24 h (in full trial populations) [coprimary endpoints]. Across trials, mirabegron 50 mg once daily also consistently significantly reduced urgency episodes and increased the volume of urine voided per micturition, generally in association with improved health-related quality of life (HR-QOL) and treatment satisfaction. Based on descriptive analyses from a 12-month trial, once-daily mirabegron 50 mg and tolterodine extended-release (ER) 4 mg were both efficacious in reducing urinary symptoms and improving HR-QOL. Mirabegron was generally well tolerated in the trials. Over 12 weeks, the adverse event rate with mirabegron 50 mg once daily was similar to that with placebo. During 12 months of treatment, 2.8 % of mirabegron 50 mg once daily recipients reported dry mouth compared with 8.6 % with tolterodine ER 4 mg once daily recipients. Mirabegron 50 mg once daily carries a low risk of QT interval prolongation. Thus, mirabegron is an efficacious new treatment for overactive bladder syndrome with a favourable tolerability profile.