Mirabegron in the treatment of overactive bladder in patients with multiple sclerosis

BACKGROUND: Lower urinary tract dysfunction is one of the leading clinical manifestations of multiple sclerosis, occurring in 50%–90% of the patients. One of the most common urinary disorders in patients with multiple sclerosis is overactive bladder. Antimuscarinic agents remain the cornerstone of drug cotherapy for neurogenic overactive bladder; however, their often limited efficacy and suboptimal tolerability highlight the need for search of new pharmacotherapeutic approaches. AIM: This study aimed to evaluate the efficacy and safety of the beta3-adrenergic receptor agonist mirabegron in the treatment of overactive bladder in patients with multiple sclerosis. METHODS: A prospective cohort study included 52 patients with multiple sclerosis and overactive bladder (mean age: 44.7 ± 12.4 years). All patients received mirabegron 50 mg once daily for 3 months. Treatment efficacy was assessed using 3-day voiding diaries and questionnaires (Patient Global Impression of Severity, Indevus Urgency Severity Scale, and Neurogenic Bladder Symptom Score), completed by patients before and after therapy. Postvoid residual volume was measured at the same time points. RESULTS: At the end of treatment, there was a significant reduction compared with baseline in the number of micturitions and urgency episodes, as well as a decrease in the proportion of patients with urgency urinary incontinence from 37 (71.2%) to 22 (42.3%) (p 0.05). A substantial decrease in mean scores on the Patient Global Impression of Severity and Indevus Urgency Severity Scale questionnaires was observed, along with a trend toward reduction in the total Neurogenic Bladder Symptom Score. Mirabegron therapy was not associated with deterioration of bladder voiding function, as evidenced by the absence of an increase in postvoid residual volume. No differences in treatment efficacy were observed according to patient age, Expanded Disability Status Scale score, clinical course or duration of multiple sclerosis, or duration of overactive bladder symptoms. Mirabegron was well tolerated. Adverse events, mainly dyspeptic symptoms, were reported in 11 (21.2%) patients. CONCLUSION: The beta3-adrenergic receptor agonist mirabegron is an effective and well-tolerated treatment option for overactive bladder in patients with multiple sclerosis, with a favorable safety profile.