Three‐year safety, efficacy and persistence data following the daily use of mirabegron for overactive bladder in the clinical setting: A Japanese post‐marketing surveillance study

OBJECTIVE: The aim of this study was to report the final 3‐year results from a surveillance study evaluating the safety, efficacy, and persistence of mirabegron for treating overactive bladder (OAB) symptoms. METHODS: Patients who had started mirabegron for the treatment of urinary urgency, daytime frequency, and urgency urinary incontinence symptoms associated with OAB were followed for 3 years. Adverse drug reactions (ADRs), residual urine volume measurements, OAB symptoms, Overactive Bladder Symptom Scores (OABSS), and treatment discontinuations were evaluated prospectively. Persistence was estimated using the Kaplan–Meier method. RESULTS: Of the 1138 patients included in the study (mean ±SD age: 71.9 ± 11.0 years; 574 [50.4%] women), 97 (8.52%) experienced 109 ADRs, with the incidence of ADRs decreasing over time (<1 year: 1.34%–2.37%; ≥1–<2 years: 0.45%–1.60%; ≥2–<3 years: 0.29%–1.10%; 3‐monthly interval data). No significant increases in residual urine volume were observed. The investigators considered mirabegron to be an effective treatment for 842 of 1082 (77.8%) patients. Significant decreases in OABSS were reported throughout (P < 0.001), and 321 (65.1%) patients achieved a minimal clinically important change (MCIC) in OABSS. Most patients who achieved an MCIC within ≤1 year continued to maintain an MCIC throughout the study. Treatment persistence rates after 1, 2, and 3 years of mirabegron treatment were 65.8%, 52.9%, and 46.7%, respectively. CONCLUSION: Over 3 years, mirabegron was well tolerated and no cumulative events or delayed ADRs were observed. Mirabegron was an effective treatment with early improvements in OABSS being maintained throughout the treatment period. High persistence was observed after the use of mirabegron.