Efficacy and safety of solifenacin succinate in Korean patients with overactive bladder: a randomised, prospective, double-blind, multicentre study

Purpose: We assessed the efficacy and safety of solifenacin compared with tolterodine for treatment of overactive bladder (OAB) in Korean patients. Materials and methods: The study was randomised, double-blind, tolterodine-controlled trial in Korea. Patients had average frequency of >= 8 voids per 24 h and episodes of urgency or urgency incontinence >= 3 during 3-day voiding diary period. Patients were randomised to 12-week double-blind treatment with either tolterodine immediate release (IR) 2 mg twice daily (TOL4) or solifenacin 5 mg (SOL5) or 10 mg (SOL10) once daily. The outcome measure was mean change in daily micturition frequency, volume, daily frequency of urgency incontinence, urgency and nocturia from baseline to week 12. Quality of life was assessed using the King's Health Questionnaire. Results: A total of 357 were randomised and 329 were evaluated for efficacy. All voiding parameters recorded in micturition diary improved after treatment in all three groups. Mean changes in volume voided were 19.30 ml (26.69%) in TOL4, 30.37 ml (25.89%) in SOL5 and 37.12 ml (33.36%) in SOL10 group (p = 0.03). Speed of onset of SOL10 efficacy on urgency incontinence was faster than that of SOL5 and TOL4. Quality of life improved in all three groups. Dry mouth was the most common adverse event; its incidence was the lowest in SOL5 group (7.63%, compared with 19.49% and 18.64% in SOL10 and TOL4 groups respectively). Conclusions: Solifenacin succinate 5 and 10 mg once daily improve OAB symptoms with acceptable tolerability levels compared with tolterodine IR 4 mg. Solifenacin 5 mg is a recommended starting dose in Korean patients with OAB.