Prospective Open Label Study of Solifenacin for Overactive Bladder in Children

Purpose: We evaluated the effect of solifenacin for urinary incontinence in children with overactive/neurogenic bladder refractory to oxybutynin or tolterodine. Materials and Methods: Pediatric patients presenting with refractory overactive bladder with incontinence were offered the opportunity to enter a prospective, open label protocol using adjusted dose regimens of 1.25 to 10 mg solifenacin. Study inclusion criteria were absent correctable neurological anomalies on magnetic resonance imaging, failure of symptoms to improve on intensive behavioral and medical (oxybutynin or tolterodine) therapy, and/or significant side effects of those agents. Followup consisted of a voiding diary, post-void residual urine measurement, urine culture, ultrasound and urodynamics. Families were questioned about continence, side effects, compliance, behavior change and quality of life. The primary end point was efficacy for continence and secondary end points were tolerability and safety. Results: Enrolled in the study were 42 girls and 30 boys. Of the patients 27 with neurogenic bladder, of whom 11 were on clean intermittent catheterization, and 45 with overactive bladder completed a minimum 3-month followup. Patients were on solifenacin a mean of 15.6 months. Mean age at study initiation was 9.0 years. Mean +/- SD urodynamic capacity improved from 146 +/- 64 to 311 +/- 123 ml and uninhibited contractions decreased from 70 +/- 29 to 20 +/- 19 cm H(2)O (p < 0.01). Continence improved in all patients, including 24 who were dry, and 42 and 6 who were significantly and moderately improved, respectively. Of the patients 50 reported no side effects while 15 had mild and 3 had moderate side effects. Four patients withdrew from the protocol due to intolerable side effects. Four patients had significant post-void residual urine (greater than 20 ml). Conclusions: In children with overactive bladder refractory to oxybutynin or tolterodine solifenacin is an effective alternative to improve symptoms. Tolerability was acceptable and the adjusted dose regimen appeared safe.