CLINICAL EFFICACY AND SAFETY OF TOLTERODINE IN THE TREATMENT OF OVERACTIVE BLADDER - A POOLED ANALYSIS

Objectives. To examine the safety, efficacy, and tolerability of tolte rodine in four randomized, double-blind, parallel, multicenter, 12-wee k studies of patients with overactive bladder, Methods. Two of the fou r studies compared tolterodine (2 mg twice daily) to oxybutynin (5 mg three times daily) and placebo, one study compared tolterodine (2 mg t wice daily) to oxybutynin (5 mg three times daily), and one study comp ared two dosages of tolterodine (1 and 2 mg twice daily) to placebo. E fficacy was determined from micturition diaries and patient perception of their bladder condition. Safety and tolerability were assessed fro m adverse events and laboratory measures. Results. A total of 1,120 pa tients were randomized and treated at 134 centers, For the primary eff icacy variable, the number of micturitions/24 hours, pooled results sh owed a significant decrease from baseline for the 1 mg tolterodine (P <0.001), 2 mg tolterodine (P <0.007), and 5 mg oxybutynin (P <0.01) gr oups, compared to placebo. Both tolterodine doses and oxybutynin signi ficantly decreased incontinence episodes/24 hours and significantly in creased volume voided/micturition, compared to placebo, Tolterodine at a dose of 2 mg twice daily and 5 mg oxybutynin twice daily were signi ficantly more effective in improving patient perception of bladder con dition than placebo. Tolterodine at a dose of 2 mg and 5 mg oxybutynin were equivalent in their effectiveness. Tolterodine at doses of 1 mg and 2 mg were tolerated significantly better than oxybutynin when adve rse events, dry mouth (both frequency and intensity), dose reductions, and patient withdrawals were considered. Conclusions. Although oxybut ynin is highly effective, its clinical utility is limited by systemic side effects that lead to frequent discontinuation of treatment or dos e reductions. Patients receiving tolterodine should not experience the se limitations and instead will get safe and long-term effective treat ment for their condition. (C) 1997, Elsevier Science Inc. All rights r eserved.