Predicting Mirabegron Treatment Response in Patients with Overactive Bladder: A Post Hoc Analysis of Data from Clinical Trials

Background: Many patients discontinue overactive bladder (OAB) treatment because of unmet treatment expectations and/or tolerability issues.Objective: To develop a model for predicting the individual treatment response to mirabegron using patient baseline characteristics. Design, setting, and participants: This was a post hoc analysis of data from eight global phase 2/3, double-blind, randomized, placebo-or active-controlled trials of mirabegron in adult patients with OAB. Intervention: Mirabegron 50 mg once-daily monotherapy for >= 12 wk. Outcome measurements and statistical analysis: Primary efficacy outcomes were the change in the mean number of micturitions and the number of incontinence episodes/24 h after 12 wk of treatment. Secondary efficacy outcomes were the change in the mean number of urgency episodes/24 h and the change in Symptom Bother score after 12 wk of treatment. Baseline demographic characteristics, OAB-related characteristics, and intrinsic and extrinsic factor variables were used to create multivariable linear regression models to predict the primary and secondary outcomes.Results and limitations: Data for 3627 patients were included. The predicted effect of mirabegron 50 mg was an average of 2.5 fewer micturition episodes/24 h (95% confi-dence interval-2.85 to-2.14) and 0.81 fewer incontinence episodes/24 h (95% confi-dence interval-1.15 to-0.46) from baseline to week 12. A higher number of urgency episodes was predictive of a larger reduction in micturition episodes; body mass index (BMI) >= 30 kg/m2, OAB symptoms for >= 12 mo, and incontinence at baseline were predic-tive of a smaller reduction. Mixed stress/urgency incontinence and more than five urgency episodes per day were predictive of greater reductions in incontinence episodes. Reductions in urgency episodes and Symptom Bother score were also predicted with mirabegron. Limitations include the exclusion of placebo groups from the analysis and the use of clinical trial rather than real-world data.Conclusions: Data from the predictive models provide new insights into the effects of modifiable factors (such as BMI) and nonmodifiable factors on treatment outcomes with mirabegron 50 mg.Patient summary: This study aimed to identify factors that could predict how patients with overactive bladder respond to mirabegron treatment to help doctors effectively treat this condition. Mirabegron treatment was associated with a lower number of urinations and occurrences of urinary incontinence per day. Factors associated with worse responses to the medication included being obese.(c) 2023 The Authors. Published by Elsevier B.V. on behalf of European Association of Urology. This is an open access article under the CC BY license (http://creativecommons. org/licenses/by/4.0/).