Efficacy and tolerability of solifenacin in elderly subjects with overactive bladder syndrome: a pooled analysis

Abstract

Background: Overactive bladder (OAB) syndrome is characterized by urinary frequency and urgency with or without urge incontinence, and often accompanied by nocturia. The prevalence of OAB increases with aging; it is a particularly common condition among the elderly, affecting at least 25% of people aged > or = 65 years.

Objective: The goal of this study was to assess the efficacy and tolerability of solifenacin 5 and 10 mg once daily for treating elderly subjects with OAB.

Methods: This was a retrospective analysis of pooled data from 4 studies. Data were analyzed from elderly subjects (aged > or = 65 years) with OAB who were treated with solifenacin in four 12-week, double-blind, Phase III, international, multicenter, randomized, parallel-group, fixed-dose, placebo-controlled studies and from elderly subjects who received solifenacin in a 40-week, open-label, flexible-dose extension trial that enrolled subjects who completed 2 of the double-blind studies. Micturition data were collected from diaries completed during the 3 days before each study visit. Efficacy end points included mean change from baseline for the number of incontinence episodes/24 hours, urgency episodes/24 hours, number of micturitions/24 hours, and volume voided/micturition. The proportion of subjects who became continent or had no urgency episodes at end point was also evaluated.

Results: The mean age of the subjects in the 12-week, double-blind studies (N = 1045; 781 women, 264 men) was 71.9 years; mean age in the 40-week extension trial (N = 509; 359 women, 150 men) was 71.2 years. The majority of subjects (74.7% in the 12-week, double-blind studies and 70.5% in the 40-week extension trial) were female, and >90% of the elderly subjects were white. The duration of OAB ranged from 0 to 66 months, and 43.7% had received previous medical therapy for OAB. The completion rate for elderly subjects was 85.5% for the 12-week, double-blind studies and 80.0% for the 40-week extension trial. Efficacy end points at week 12 of double-blind treatment demonstrated statistically significant improvements in the symptoms of OAB with solifenacin compared with placebo. Mean (SE) changes in number of incontinence episodes/24 hours were -1.5 (0.17) for the 5-mg dose and -1.9 (0.14) for the 10-mg dose compared with -1.0 (0.14) for placebo (P = 0.013 for the 5-mg dose and P < 0.001 for the 10-mg dose, vs placebo); mean (SE) changes in the number of urgency episodes/24 hours were -3.2 (0.27) for the 5-mg dose and -3.2 (0.19) for the 10-mg dose compared with -1.6 (0.18) for placebo (P < 0.001 for both doses vs placebo); mean (SE) changes in the number of micturitions/24 hours were -2.0 (0.17) for the 5-mg dose and -2.5 (0.13) for the 10-mg dose compared with -1.1 (0.13) for placebo (P < 0.001 for both doses vs placebo); mean (SE) changes in the volume voided/micturition were 30.2 (3.24) mL for the 5-mg dose and 46.2 (2.55) mL for the 10-mg dose, compared with 9.1 (2.39) mL for placebo (P < 0.001 for both doses vs placebo). The proportion of subjects with restoration of continence was 49.1% and 47.3% of the 5- and 10-mg treatment groups, respectively, compared with 28.9% of the placebo group (P < 0.001 for both doses vs placebo). The proportion of subjects with resolution of urgency was 34.6% and 24.9% for the 5- and 10-mg treatment groups, respectively, compared with 16.9% of the placebo group (P < 0.001 for the 5-mg dose and P < 0.01 for the 10-mg dose). Improvements in incontinence, urgency, and micturitions were maintained during the 40-week extension trial. The most common adverse events in both the double-blind and extension trials were dry mouth, constipation, and urinary tract infection. Most adverse events were mild to moderate in nature and did not result in treatment discontinuation.

Conclusions: In these pooled analyses, solifenacin 5 and 10 mg once daily were efficacious and well tolerated in the treatment of these elderly subjects with OAB. Solifenacin therapy was also associated with a high level of persistence in a 40-week extension trial.