Long-term safety, tolerability and efficacy of fesoterodine in subjects with overactive bladder symptoms stratified by age: Pooled analysis of two open-label extension studies

Background: Previous work has demonstrated the efficacy and safety of fesoterodine in older and younger subjects with overactive bladder (OAB) symptoms. The effect of long-term fesoterodine treatment in different age groups has not been assessed. Objective: The aim was to determine the impact of age on the safety, tolerability and efficacy of long-term treatment with fesoterodine 8mg in subjects with OAB syndrome. Methods: This was a pooled analysis of two identically designed open-label extensions of 12-week, randomized, double-blind, placebo-controlled studies. The setting was urology and general practice offices. Subjects who participated in the 12-week, double-blind studies and opted to continue long-term, open-label treatment with fesoterodine were included. Subjects were initiated on fesoterodine 8mg/day at open-label baseline. After 1 month, subjects could elect dose reduction to 4mg/day and subsequent re-escalation to 8 mg; each was permitted once annually. Maximal duration of open-label treatment ranged from 24 to 36 months. Discontinuations, subject-reported treatment tolerance, and efficacy (3-day diaries) were assessed at open-label baseline and months 1, 4, 8, 12 and 24. Results: Atotal of 890 subjects were treated (age <45 years, n = 140; 45-64 years, n = 444; 65-74 years, n = 208; ±75 years, n = 98); 49% continued treatment for ±24 months (age <45 years, 43%; 45-64 years, 54%; 65-74 years, 50%; ±75 years, 37%). Seventy-seven percent of subjects remained on fesoterodine 8mg throughout treatment; this rate was highest among subjects aged ±75 years (age <45 years, 72%; 45-64 years, 77%; 65-74 years, 73%; ±75 years, 87%). Approximately 80% of continuing subjects were receiving fesoterodine 8mg at each visit after open-label baseline up to 36 months. No new or unexpected safety signals were observed in any age group. Most subjects reported 'good' or 'excellent' treatment tolerance throughout the study (age <45 years, ±90%; 45-64 years, ±93%; 65-74 years, ±85%; ±75 years, ±86%). Dry mouth, the most commonly reported treatment-emergent adverse event, was lowest among subjects aged ±75 years (age <45 years, 31%; 45-64 years, 30%; 65-74 years, 32%; ±75 years, 26%). Rates of discontinuation due to dry mouth were low in all age groups. Significant improvements in all diary variables, including urgency urinary incontinence episodes per 24 hours, micturitions per 24 hours, urgency episodes per 24 hours, and mean voided volume per micturition, observed between double-blind baseline and openlabel baseline were sustained or increased during open-label treatment in the overall population and all age groups. Conclusions: Long-term fesoterodine (administered primarily as 8 mg) was well tolerated and associated with sustained improvements in OAB symptoms, irrespective of age.