Project Summary

PCORI has identified urinary incontinence, or UI, among women as an important research topic. Although many nonsurgical treatments work well to improve UI symptoms, few studies have compared these treatments. Patients, caregivers, clinicians, and others want to learn: How do different nonsurgical treatment options compare for improving patient-centered outcomes among nonpregnant women with UI? To help answer this question, PCORI launched an initiative in 2021 on Nonsurgical Options for Women with Urinary Incontinence. The initiative funded this research project and others.

This research project is in progress. PCORI will post the research findings on this page within 90 days after the results are final.

What is the research about?

Urgency urinary incontinence, or UUI, is a health problem that causes an urgent need to urinate and a loss of bladder control. UUI is common among women and can worsen quality of life. 

Doctors first use pelvic floor therapy to treat UUI. This treatment includes exercises to strengthen the muscles that control the flow of urine. If the exercises don’t help, doctors may prescribe an anticholinergic medicine. But for many women, neither treatment works well to improve the symptoms of UUI. 

In this study, the research team is comparing two ways to treat UUI when initial treatments don’t work well. The first way is a beta-agonist medicine. The second way is Botox injections in the bladder. Both help to relax the muscles of the bladder, which can help treat the urge to urinate.

Who can this research help?

Results may help women with UUI and their doctors when considering ways to treat UUI when initial treatments aren’t successful.

What is the research team doing?

The research team is enrolling 432 women ages 18 and older with UUI. The women are from five sites across the country. These women have tried exercises and anticholinergic medicine in the past and still report that their symptoms still bother them. The team is assigning women by chance to receive beta-agonist medicine or Botox bladder injections.

Women receiving a beta-agonist take the medicine daily. Women receiving Botox receive one injection. After three months, patients talk to their doctor about whether they should receive more injections.

After 3, 6, 9, and 12 months, the research team is surveying patients about: 

  • How well treatment improves their UUI symptoms 
  • How satisfied they are with their treatment<
  • Their quality of life
  • Side effects from treatment

Patients with UUI, social support groups, and community leaders are helping to plan and conduct this study. 

Research methods at a glance

Design ElementDescription
DesignRandomized controlled trial
Population432 women ages 18 and older for whom behavior therapy, pelvic floor exercises, and anticholinergic medicine therapy was unsuccessful
  • Beta-agonist medicine including mirabegron or vibegron

  • Intradetrusor onabotulinumtoxin A, or Botox, bladder injection

Primary: UUI symptom severity, treatment satisfaction

Secondary: UUI quality of life, cognitive function, sexual function, side effects, adverse events, treatment adherence

Timeframe  Timeframe Length of follow-up for collecting data on primary outcomes. View Glossary 3-month follow-up for primary outcomes 

*Increase Diversity and Advance Health Equity Funding Supplement
This study received supplemental funding to build on existing PCORI-funded comparative clinical effectiveness research (CER) studies to leverage meaningful engagement of affected/relevant communities to ensure that a diverse and inclusive study population can be achieved.

Project Information

Vivian Sung, MD, MPH
Women and Infants Hospital-Rhode Island
Beta-Agonist versus onabotulinumtoxinA Trial for Urgency Urinary Incontinence (Best Trial)

Key Dates

March 2022
December 2028


Award Type
Health Conditions Health Conditions These are the broad terms we use to categorize our funded research studies; specific diseases or conditions are included within the appropriate larger category. Note: not all of our funded projects focus on a single disease or condition; some touch on multiple diseases or conditions, research methods, or broader health system interventions. Such projects won’t be listed by a primary disease/condition and so won’t appear if you use this filter tool to find them. View Glossary
Populations Populations PCORI is interested in research that seeks to better understand how different clinical and health system options work for different people. These populations are frequently studied in our portfolio or identified as being of interest by our stakeholders. View Glossary
Intervention Strategy Intervention Strategies PCORI funds comparative clinical effectiveness research (CER) studies that compare two or more options or approaches to health care, or that compare different ways of delivering or receiving care. View Glossary
State State The state where the project originates, or where the primary institution or organization is located. View Glossary
Last updated: March 27, 2024