Mirabegron 25 Mg Monotherapy is Safe but Less Effective in Male Overactive Bladder Patients with Bladder Outlet Obstruction

The treatment results of mirabegron in male overactive bladder (OAB) patients with bladder outlet obstruction (BOO) are scarce. This study compared the therapeutic efficacy and safety of mirabegron monotherapy in male OAB patients with and without BOO.

Male OAB patients aged ≥20 years, with or without BOO, receiving mirabegron 25 mg, once daily monotherapy were prospectively enrolled. The treatment results were assessed using global response assessment (GRA), international prostate symptom score (IPSS) and subscores, overactive bladder symptom score (OABSS), patient perception on intensity of urgency scale (PPIUS), patient perception of bladder condition (PPBC), and quality of life index (QoL-I) at 1 and 3 months after treatment.

Of the 289 enrolled patients (mean age, 71.2 years), 207 (71.6%) did not have BOO and 82 (28.4%) had BOO. The baseline OAB symptoms were similar between patients with and without BOO. After mirabegron treatment, the satisfactory rate (GRA≧1) were similar between those without BOO (61.3%) and with BOO (57.1%). The improvement of QoL-I and PPBC were also found in both groups. However, only patients without BOO had significantly improvement of IPSS and subscores, OABSS, and PPIUS. Although most adverse events (AEs) were mild, patients with BOO had significantly higher AEs rate (18.6%) than those without BOO (8.2%, p=0.026).

Mirabegron monotherapy in male OAB patients with BOO was safe. However, the storage symptoms improvement was less in patients with BOO and the rate of adverse events was higher.

Urology. 2018 Apr 06 [Epub ahead of print]

Chun-Hou Liao, Hann-Chorng Kuo

Department of Urology, Cardinal Tien Hospital and Fu-Jen Catholic University., Department of Urology, Buddhist Tzu Chi General Hospital and Tzu Chi University, Hualien, Taiwan. Electronic address: .