Clinical safety, tolerability and efficacy of combination tolterodine/pilocarpine in patients with overactive bladder

Abstract

Aims: The purpose of this study was to assess the safety, tolerability and impact on overactive bladder (OAB) symptoms of a novel combination of tolterodine immediate-release (IR) 2 mg and delayed-release pilocarpine 9 mg in patients with OAB.

Methods: Eligible patients with OAB were randomised to each of three treatments [tolterodine/pilocarpine (2/9 mg), tolterodine IR 2 mg or placebo] twice daily for 4 weeks in a double-blind, crossover fashion. At the end of the 12-week, double-blind treatment period, patients could enter an open-label extension during which they were re-randomised to either tolterodine/pilocarpine (3/13.5 mg) twice daily or tolterodine extended-release 4 mg once daily for 12 weeks.

Results: A total of 138 patients were randomised to double-blind medication. Both tolterodine/pilocarpine (2/9) and tolterodine IR 2 mg significantly reduced incontinence episodes and daily micturitions (p < 0.001 vs. placebo), with similar reductions in symptoms observed between active treatment groups. Tolterodine/pilocarpine (2/9) was associated with consistently lower Visual Analogue Scale (VAS) scores for all dry mouth parameters compared with tolterodine alone. Salivary flow over a 3 h period remained fairly constant after tolterodine/pilocarpine (2/9) administration, similar to placebo, but decreased markedly after administration of tolterodine alone. In the extension study, patients receiving tolterodine/pilocarpine (3/13.5) reported comparable dry mouth VAS scores to tolterodine extended-release alone without additional side effects or loss of efficacy. The combination was well tolerated, and the adverse effects observed were consistent with the known safety profiles of tolterodine and pilocarpine.

Conclusions: A combination of tolterodine/pilocarpine (2/9) effectively reduced the incidence of dry mouth compared with tolterodine IR alone while maintaining treatment efficacy in OAB.