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Updated: Sep 19, 2025

Bladder Smooth Muscle Strip Contractility as a Method to Evaluate Lower Urinary Tract Pharmacology
Published on: August 18, 2014
Comparative efficacy and adverse effects of β3-agonists and antimuscarinics in overactive bladder: a network and
Wenlin Huang1, Xueqin Zheng2, Jinyang Luo3
1Department of Urology, Zhuzhou Hospital Affiliated to Xiangya School of Medicine, Central South University, Zhuzhou, China.
Background:
To assess and compare the efficacy and adverse effects of β3-adrenergic receptor agonists (vibegron and mirabegron), alone and with antimuscarinic agents, in treating overactive bladder (OAB) via network meta-analysis (NMA) and component network meta-analysis (cNMA).
Materials And Methods:
A search across multiple databases was done for Phase II/III RCTs from Jan. 2010 to June 2024. Adults with OAB or overactive bladder symptom score (OABSS) ≥ 3 were included. Trials evaluating vibegron (monotherapy/combination) and mirabegron combination therapies were eligible. Excluded were nonrandomized studies, secondary OAB, and long-term cardiovascular disease cases. Primary outcomes included micturition frequency (MF), urgency episodes (UE), urge urinary incontinence (UUI), and mean voided volume (MVV). Secondary outcomes were adverse events leading to treatment discontinuation (AELTD), adverse events (AEs), serious adverse events (sAEs), dry mouth, and constipation. Data analysis used the netmeta R package with both NMAs and cNMA.
Results:
Twelve studies (11,374 participants) were included. Vibegron outperformed mirabegron and antimuscarinics in reducing micturition frequency, with 100 mg vibegron showing the greatest reduction (SMD = - 0.87, 95% CI - 1.16 to - 0.59). Combination therapies generally had better efficacy in improving UE and UUI than monotherapies, except mirabegron 50 mg + tamsulosin. No significant MVV differences between treatments and controls. For AEs, there were no significant differences in overall AEs or AELTD between treatments and controls. But higher doses and combination therapies had higher risks of dry mouth and constipation. Component network meta-analysis (cNMA) showed greater reductions in micturition frequency, suggesting possible negative interactions, whereas standard NMA showed synergistic effects on urgency episodes (UE) and mean voided volume (MVV).
Conclusion:
β3-agonists, especially vibegron, are effective for OAB symptoms (MF and UUI), both alone and with antimuscarinics. For short-term treatment, combination therapies seem superior to monotherapies in symptom control.
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