Treatment Patterns with Mirabegron and Antimuscarinics for Overactive Bladder: A Prospective, Registry Study in Taiwan and South Korea (FAITH)

Abstract

Introduction: This study aimed to assess overactive bladder (OAB) treatment patterns and factors associated with effectiveness and persistence.

Methods: A prospective, longitudinal, observational registry study of adults starting OAB therapy with mirabegron or antimuscarinics was undertaken. Primary endpoints were time from treatment initiation to discontinuation/switching; proportion who discontinued/switched; and reasons for discontinuation/switching. Secondary endpoints included OAB Symptom Score (OABSS), OAB Questionnaire: Short Form, and OAB Bladder Assessment Tool scores; factors associated with effectiveness and persistence; and safety.

Results: In total, 556 patients initiating mirabegron and 250 initiating antimuscarinics were enrolled. There was no treatment switch, change, or discontinuation in 68.5% of the mirabegron initiator group and median time to treatment change was not reached. Mean initial treatment duration was 130.8 days. In multivariable models, baseline OABSS was the only variable significantly associated with change from baseline in OABSS, and patients with mild and moderate OAB had significantly better persistence with mirabegron than those with severe OAB. Urinary tract infection was the most common adverse event with mirabegron. There was no treatment switch, change, or discontinuation in 60.4% of the antimuscarinics initiator group and median time to treatment change was not reached. Solifenacin was the most frequent initial treatment (66.0%). Mean treatment duration was 122.2 days. In multivariable models, baseline OABSS was the only variable significantly associated with change from baseline in OABSS, while patients with OAB medication in the 12 months before enrollment had significantly better persistence with antimuscarinics than those with no previous OAB medication. Dry mouth was the most common adverse event with antimuscarinics.

Conclusions: Mirabegron and solifenacin were commonly prescribed as first-line OAB medications. There was no treatment switch, change, or discontinuation in more than 60% of the mirabegron initiator and antimuscarinics initiator groups. Mean initial treatment duration was 130.8 days and 122.2 days for mirabegron and antimuscarinics, respectively. Graphical Abstract available for this article.

Trial registration: ClinicalTrials.gov NCT03572231.

Keywords: Non-interventional; Overactive bladder; Persistence; Prospective study; β3-adrenoceptor agonist.

Fig. 1

Patient disposition. AE adverse event, AM antimuscarinics, FAS full analysis set, M mirabegron, SAS safety analysis set. “Completed” was defined as patients who were not lost to follow-up for any reason, completed one or more study visits, and whose “Primary Investigational Period Status” was marked as “Complete” by the study staff, irrespective of the days spent on treatment. ^a“Reasons for study discontinuation” population refers to patients who were lost to follow-up for any reason and/or did not complete one or more study visits (total, n = 322 patients; M, n  = 233 patients; AM, n  = 89 patients). ^b“Reasons for treatment discontinuation” population refers to any patient who did not receive either M or AM for at least 154 days during the study (total, n = 392 patients; M, n  = 277 patients; AM, n  = 115 patients)

Fig. 2

For the mirabegron initiator group the a proportion of patients who discontinued OAB treatment or switched to another treatment or dose (FAS), b Kaplan–Meier curve for time to treatment change in patients with OAB (FAS), c persistence rates (FAS), and d persistence rates by age (FAS). CI confidence interval, FAS full analysis set, OAB overactive bladder. Time to treatment change was cut off at 183 days after treatment initiation. Treatment change includes treatment switch or dose escalation/reduction or discontinuation. One patient took more than one medication for OAB (i.e., mirabegron and tamsulosin) during the study

Fig. 3

For the mirabegron initiator group the a change from baseline in OABSS (FAS) and b unadjusted change from baseline in quality-of-life measures (FAS). CI confidence interval, FAS full analysis set, HRQoL health-related quality of life, OAB overactive bladder, OAB-BAT OAB Bladder Assessment Tool, OAB-Q-SF OAB Questionnaire: Short Form, OABSS, OAB Symptom Score, TS-VAS Treatment Satisfaction Visual Analog Scale. One patient took more than one medication for OAB

Fig. 4

AE outcomes with mirabegron (SAS). AE adverse event, SAE serious AE, SAS safety analysis set, UTI urinary tract infection. If more than one treatment group (i.e., mirabegron and antimuscarinics) overlapped with an AE, the AE was counted under both treatment groups. For the analysis of AEs, the number of patients in the mirabegron group included patients who received at least one treatment with mirabegron at any time during the study to account for treatment overlap

Fig. 5

For the antimuscarinics initiator group the a proportion of patients who discontinued OAB treatment or switched to another treatment or dose (FAS), b Kaplan–Meier curve for time to treatment change in patients with OAB (FAS), c persistence rates (FAS), and d persistence rates by age (FAS). CI confidence interval, FAS full analysis set, OAB overactive bladder. Time to treatment change was cut off at 183 days after treatment initiation. Treatment change includes treatment switch or dose escalation/reduction or discontinuation

Fig. 6

For the antimuscarinics initiator group the a change from baseline in OABSS (FAS) and b unadjusted change from baseline in quality-of-life measures (FAS). CI confidence interval, FAS full analysis set, HRQoL health-related quality of life, OAB-BAT OAB Bladder Assessment Tool, OAB-Q-SF OAB Questionnaire: Short Form, OABSS OAB Symptom Score, TS-VAS Treatment Satisfaction visual analog scale

Fig. 7

AE outcomes with antimuscarinics (SAS). AE adverse event, SAE serious AE, SAS safety analysis set, UTI urinary tract infection. If more than one treatment group (i.e., mirabegron and antimuscarinics) overlapped with an AE, the AE was counted under both treatment groups. For the analysis of AEs, the number of patients in the antimuscarinics group included patients who received at least one treatment with antimuscarinics at any time during the study to account for treatment overlap