A randomised, double-blind, parallel design, multi-institutional, non-inferiority phase IV trial of imidafenacin versus fesoterodine for overactive bladder

AimsOur objective was to compare the efficacy and safety of imidafenacin over fesoterodine in patients with overactive bladder (OAB). MethodsThis study is a randomised, double-blind, parallel-group, fesoterodine-controlled study in patients with continuous OAB symptoms for 3months, daily mean voiding frequency (DMVF) 8, and daily mean urgency or urgency incontinence frequency 2. A twice-daily 0.1mg imidafenacin with placebo, or once-daily 4mg fesoterodine with placebo were administered for 12weeks. The primary efficacy end-point was the difference in DMVF at 12weeks. The secondary efficacy end-points were differences in daily mean: (i) voiding frequency at 4 and 8weeks; (ii) urgency frequency; (iii) urgency incontinence frequency; (iv) incontinence frequency; (v) nocturia frequency; and (vi) quality of life score. The variables for safety analysis were adverse events, vital signs, residual urine volume and clinical laboratory tests. An efficacy analysis was conducted in per-protocol patients and the safety analysis was conducted in all randomised patients. ResultsThe differences in DMVF at 12weeks were -3.383.63 and -2.45 +/- 3.73 in the imidafenacin and fesoterodine groups, respectively, and the difference was not significant between the two groups. Imidafenacin was non-inferior to fesoterodine, and the lower limit of 95% two-sided confidence intervals was -0.53. The other six secondary end-points and variables for safety analysis showed no difference between the two groups. ConclusionsImidafenacin was non-inferior to fesoterodine in terms of efficacy, and showed no significant difference in terms of safety.