Dual Therapy for Refractory Overactive Bladder in Children: A Prospective Open-Label Study.

PURPOSE: Mirabegron (ß3 adrenoreceptor agonist) is a new molecule with a mechanism of action distinct from antimuscarinics. Combination therapy with solifenacin was recently studied in an adult population. We evaluated the efficacy and safety of mirabegron as add-on therapy to treat urinary incontinence in children with idiopathic overactive bladder refractory/intolerant to antimuscarinics. MATERIALS AND METHODS: A prospective off-label study using add-on regimens of mirabegron was conducted in pediatric patients presenting with no symptom improvement while undergoing intensive behavioral and medical therapies and/or significant side effects while undergoing antimuscarinic dose escalation. Our primary outcome was better reported efficacy than with the use of prior antimuscarinic monotherapy. Secondary end points were tolerability, safety and satisfaction. Efficacy and tolerability were assessed based on voiding diaries, post-void residuals, urine cultures, electrocardiograms and vital signs. Families were questioned regarding continence, side effects and compliance. Wilcoxon signed-rank test was used for statistical analysis. RESULTS: A total of 35 patients were recruited at a median age of 10.3 years and were administered add-on mirabegron for a median of 16.4 months. Median bladder capacity improved from 50% to 74% expected bladder capacity (p <0.001). Continence improved in all patients, with 12 being completely dry. Post-void residual was increased in 2 patients and 1 urinary tract infection was reported. Seven patients reported mild or moderate side effects, with 2 withdrawals because of side effects (1 patient) and post-void residual (1). CONCLUSIONS: Add-on mirabegron appears to be a safe alternative for children with refractory overactive bladder. Dual therapy is well tolerated and adjusted dose regimen appears safe in this first pediatric study.

Prospective Pilot Study of Mirabegron in Pediatric Patients with Overactive Bladder.

BACKGROUND: Antimuscarinics are the pharmacologic mainstay of overactive bladder (OAB) management, but side effects limit their use. Mirabegron, a new molecule with a distinct mechanism of action (ß3-adrenoreceptor agonist), was recently approved as monotherapy for idiopathic OAB in adults but has not been studied in the pediatric population. OBJECTIVE: To evaluate the efficacy and safety of mirabegron to treat urinary incontinence in children with idiopathic OAB who were refractory to and/or intolerant of antimuscarinics. DESIGN, SETTING, AND PARTICIPANTS: A prospective off-label study using mirabegron was conducted. Pediatric patients without symptom improvement under behavioral and medical therapies and/or with significant side effects with at least two different antimuscarinic agents were recruited. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Our primary outcome was better reported efficacy than with the use of prior anticholinergic medication. Secondary end points were tolerability, safety, and satisfaction. Efficacy and tolerability were assessed with voiding diaries, postvoid residuals, urine cultures, electrocardiogram, and vital signs. Families were questioned for continence, side effects, compliance, and Patient Perception of Bladder Condition (PPBC) questionnaire. The Wilcoxon rank sum test and Wilcoxon signed rank test were used for statistical analysis. RESULTS AND LIMITATIONS: A total of 58 patients were recruited at a median age of 10.1 yr and were on mirabegron for a median of 11.5 mo. Median bladder capacity improved from 150ml to 200ml (p<0.001). Continence improved in 52 of 58, with 13 being completely dry. Median PPBC improved from 4.0 to 2.0 (p<0.001). Eight patients reported mild or moderate side effects. Absence of a placebo group is a limitation of the study. CONCLUSIONS: Mirabegron, a novel first-in-class therapy, appeared as a safe and effective alternative for children with idiopathic OAB refractory to antimuscarinics. PATIENT SUMMARY: We evaluated the efficacy and safety of mirabegron to treat incontinence in pediatric patients. Continence, median voided volumes, and quality of life were improved after the introduction of mirabegron, and few side effects were reported.

Double anticholinergic therapy for refractory neurogenic and nonneurogenic detrusor overactivity in children: Long-term results of a prospective open-label study.

INTRODUCTION: In this study, we optimize pharmacotherapy in children who failed anticholinergic monotherapy by simultaneous administration of 2 anticholinergics (oxybutynin and/or tolterodine and/or solifenacin). METHODS: This report is an update of our previously published study on double anticholinergic regimen in children with refractory incontinence due to neurogenic (NDO) and non-neurogenic (DO) detrusor overactivity. Patients with an insufficient response (clinically/urodynamically) to an optimized dose of a single anticholinergic (oxybutynin or tolterodine) received a second anticholinergic (tolterodine or solifenacin), in addition to the pre-existing medication. The primary end-point was efficacy (continence) and the secondary end-points were tolerability and safety. The Patient Perception of Bladder Condition (PPBC) scale was used to rate subjective improvement of patients. RESULTS: In total, 56 patients with DO (n = 31) or NDO (n = 25) were enrolled at a mean age of 11.4 ± 3.5 years and were followed for a minimum of 3 months. The duration of double treatment was 36 ± 23 months. Our results found that 23 patients became dry, 18 improved significantly and 15 improved moderately. Urodynamic capacity improved from 158 ± 87 mL to 359 ± 148 mL and maximal pressure of contractions decreased from 76 ± 24 to 22 ± 22 cmH2O (p < 0.0001). The overall success rate was 82%, since 10 patients discontinued treatment for unsatisfactory clinical response or bothersome side effects. No side effects were reported by 28 patients, mild side effects by 20, moderate side effects by 8; 2 patients withdrew from the study due to their side effects. Of the 35 patients who voided spontaneously, 8 developed post-void residuals (>20%). CONCLUSIONS: With a larger cohort and prospective follow-up, we reiterated that double anticholinergic regimen in children with DO or NDO refractory to anticholinergic monotherapy is a feasible and efficient approach.

Long-term use of solifenacin in pediatric patients with overactive bladder: Extension of a prospective open-label study.

INTRODUCTION: We evaluate the efficacy and safety of solifenacin to treat incontinence in children with non-neurogenic (DO) or neurogenic detrusor overactivity (NDO) refractory to oxybutinin or tolterodine. METHODS: We updated and extended our previously published non-randomized uncontrolled study on open-label use of adjusted-dose regimens of solifenacin (1.25-10 mg) in children with refractory incontinence. The follow-up included voiding diaries, post-void residuals, urine cultures, ultrasounds and urodynamic studies. Clinical data were updated as of September 2012. Subjective improvement was assessed with the Patient Perception of Bladder Condition (PPBC) scale. The primary end point was efficacy toward continence and secondary end points were tolerability and safety. RESULTS: Overall, 244 patients (112 girls, 132 boys) were enrolled; 53 with NDO and 191 with DO. Minimal follow-up was 5 months, the mean duration of treatment was 21.0 months and the mean age at initiation was 9.2 years. Urodynamic capacity improved from 145 ± 76 mL to 339 ± 152 mL and the amplitude of uninhibited contractions decreased from 66 ± 26 to 20 ± 20 cmH2O (p < 0.0001). The overall success rate is 91%, and more specifically 94% for non-neurogenic and 79% for neurogenic, which is significantly different (p = 0.013). Twenty-three patients discontinued treatment for unsatisfactory clinical response or bothersome side effects. No side effects were reported by 175 patients, mild by 46, moderate by 9, and 14 withdrew due to their side effects. Ten patients developed post-void residuals of ≥20 mL. CONCLUSION: Although higher in the non-neurogenic group, high subjective and objective success rates were maintained over a longer follow-up with an adjusted-dose regimen of solifenacin to treat pediatric NDO or DO refractory to oxybutynin or tolterodine. Moreover, we found acceptable tolerability and safety profiles.