Long-term safety and efficacy of the novel β -adrenoreceptor agonist vibegron in Japanese patients with overactive bladder: A phase III prospective study.

Objectives: To evaluate the long-term safety and efficacy of vibegron 50 mg and 100 mg, a novel β -adrenoreceptor agonist, in Japanese patients with overactive bladder.

Methods: This was a 1-year, multicenter, open-label, non-controlled study. After a 1-week observation phase, patients were treated with vibegron for 52 weeks. When the efficacy was insufficient after an 8-week treatment with 50 mg, the dose was increased to 100 mg and maintained for an additional 44 weeks.

Results: Among a total of 169 patients receiving one or more doses of vibegron, 118 (69.8%) received vibegron 50 mg for 52 weeks, and the dose was increased to 100 mg in 51 (30.2%) patients. The incidence of drug-related adverse events was 18.1% (21/116) in the vibegron 50 mg group and 11.8% (6/51) in the vibegron 100 mg group. Most frequent drug-related adverse events were dry mouth (3.0%), residual urine volume increased (3.0%), constipation (2.4%) and cystitis (1.8%). Statistically significant changes in overactive bladder symptom variables (daily means of micturitions, urgency episodes, urgency incontinence episodes, incontinence episodes and night-time frequency) from baseline were observed at week 4 and maintained until week 52. The condition of patients who did not respond well to vibegron 50 mg was much improved by increasing the dose to 100 mg. Vibegron improved the quality of life, and the proportion of patients' satisfaction after the treatment with vibegron was high.

Conclusions: Long-term (52-week) treatment with vibegron is safe, well-tolerated and effective in patients with overactive bladder.