Long-term safety and efficacy of antimuscarinic add-on therapy in patients with overactive bladder who had a suboptimal response to mirabegron monotherapy: A multicenter, randomized study in Japan (MILAI II study)

Objectives

To evaluate the long‐term safety (primary objective) and efficacy (secondary objective) of antimuscarinic add‐on therapy in patients receiving mirabegron.

Methods

During a 2‐week screening period, patients (aged ≥20 years, mirabegron treatment for ≥6 weeks, residual overactive bladder symptoms) received mirabegron 50 mg once daily. These patients were subsequently randomized to 52 weeks’ treatment with mirabegron 50 mg/day plus an antimuscarinic (solifenacin 5 mg, propiverine 20 mg, imidafenacin 0.2 mg, or tolterodine 4 mg) with the potential to double the antimuscarinic dose (except for tolterodine) at week 8. Safety assessments included treatment‐emergent adverse events, vital signs, 12‐lead electrocardiograms, post‐void residual volume, and laboratory evaluations. Efficacy was assessed using changes from baseline in overactive bladder symptom score total score; overactive bladder questionnaire short form score; micturitions, urgency episodes, urinary incontinence episodes, and urgency urinary incontinence episodes/24 h; mean volume voided per micturition; and number of night‐time micturitions.

Results

Overall, 80.2% of patients (88.1% women, mean age 65 years) experienced at least one treatment‐emergent adverse event, with similar rates for all treatments. The adverse events most commonly reported were dry mouth, nasopharyngitis, and constipation. No marked change was observed in systolic or diastolic blood pressure for any treatment, although pulse rate increased slightly in the mirabegron and propiverine, and mirabegron and tolterodine groups. For all treatments, significant improvements were observed in all efficacy parameters, including overactive bladder symptom score total and questionnaire short form scores.

Conclusions

Antimuscarinic add‐on therapy is well tolerated and effective after initial treatment with mirabegron in patients with overactive bladder symptoms.

Nocturia, nocturnal incontinence prevalence, and response to anticholinergic and behavioral therapy

To determine whether participants in the behavior enhances drug reduction of incontinence (BE-DRI) trial experienced reduction in the frequency of nocturia and/or nocturnal leakage during treatment with antimuscarinic phamacotherapy with or without additional behavioral therapy. We analyzed urinary diary data relating to nocturia and nocturnal incontinence before and after 8 weeks of study treatment in the BE-DRI trial, in which patients were randomly assigned to receive drug therapy with tolterodine tartrate extended-release capsules 4 mg alone or in combination with behavioral training. Chi-square tests assessed whether nocturia and nocturnal incontinence prevalence varied by treatment arm and paired t tests assessed the change in mean frequency of nocturia and nocturnal leakage. Among 305 women, 210 (69%) had an average of at least one nocturia episode at baseline. There were small but statistically significant differences (p < 0.001) in mean nocturia frequency and nocturnal incontinence frequency with both treatments after 8 weeks, but no significant difference between study treatment groups. Among these urge incontinent women, tolterodine with or without supervised behavioral therapy had little impact on either nocturic frequency or nocturnal incontinence.