The phase 4 COMPOSUR study followed patients in the United States who had previously used other OAB medications. All participants began taking a once-daily 75 mg dose of vibegron, a beta-3 adrenergic agonist, and accessed the medication through their standard insurance plans. The study enrolled 403 patients with a mean age of 56.1 years, of whom 71.7% were women and 14.1% were Black or African American.
Study Details and Patient Group
The COMPOSUR study was a prospective observational trial conducted at 45 US sites. It enrolled 403 patients between October 2021 and July 2023. Participants were divided into two groups: 142 had previously used anticholinergic therapy, and 261 had used mirabegron, sometimes with an anticholinergic. The research team tracked patient-reported outcomes using monthly questionnaires, specifically the OAB Satisfaction With Treatment Questionnaire (OAB-SAT-q) and the OAB Questionnaire short form (OAB-q), with 234 (58.1%) of patients completing the full study duration.
Satisfaction and Treatment Preference
After 12 months, the average satisfaction score was 65.6 on a questionnaire where a score of 60 or higher indicates satisfaction. Among patients with at least one postbaseline assessment, 69.0% (95% CI, 64.1%-73.9%) were consistently satisfied, meaning they answered satisfied or higher on all three satisfaction questions. A different analysis, which counted patients who dropped out early as non-satisfied, showed a 48.6% (95% CI, 43.5%-53.7%) satisfaction rate.
Among the patients who answered a preference question, 77.9% said they preferred vibegron over their previous OAB treatment. This preference was noted in both patient subgroups.
Persistence Rates and Side Effects
Treatment persistence, an exploratory measure based on patient-reported treatment status, was high initially. It was 94.2% at one month, 84.9% at three months, and 73.0% at six months. By 12 months, persistence had fallen to 59.8% (95% CI, 54.7%-64.6%). The most common reasons for stopping vibegron were lack of efficacy (24.9%) and voluntary withdrawal (23.7%), followed by cost (10.1%) and safety concerns (7.7%).
The study found vibegron to be safe. Adverse events were reported in 36.0% of patients, with the most common being urinary tract infection (4.0%) and headache (2.7%). Serious side effects occurred in 2.0% of patients. One patient died, and the death was unrelated to the drug. Urinary retention occurred in 1.0% and hypertension in 0.7%, and 7.9% of all patients stopped vibegron because of a treatment-emergent adverse event.
Symptom scores improved significantly. At the 12-month mark, patients reported a 26.9-point drop in symptom severity and a 24.5-point increase in quality of life scores. This improvement was noticeable as early as the first month. Dissatisfied patients may have been more likely to leave the study, as 41.9% of participants discontinued treatment.
The authors noted that their 12-month persistence rate is similar to data from other studies of OAB medications, though they caution that direct comparisons are difficult due to different study methods. They also stated the findings may not apply to patients who have never been treated for OAB. The research was funded by Sumitomo Pharma America, and several authors had financial ties to the company. The study was published in Ther Adv Urol. 2026;18:1-13. doi:10.1177/17562872261497025 Dmochowski RR, Rovner ES, Kennelly MJ, et al. Satisfaction and persistence with vibegron in the first 6 months of overactive bladder treatment: interim results of the phase 4, real-world COMPOSUR study.