To evaluate the efficacy and tolerability of flexible-dose fesoterodine vs placebo in subjects with overactive bladder (OAB).

In a 12-week double-blind trial, subjects were randomized to fesoterodine 4 mg or placebo once daily, taken within 4 hours of bedtime. At week 2, subjects could increase the fesoterodine dose to 8 mg (sham escalation for placebo). Subjects completed 3-day bladder diaries, Patient Perception of Bladder Condition, and Urgency Perception Scale at baseline and weeks 2, 6, and 12 as well as OAB Questionnaire at baseline and week 12.

Of 883 subjects, 63% and 73% of the fesoterodine (n = 438) and placebo (n = 445) groups, respectively, opted for dose escalation. Week 12 improvements from baseline in total micturitions, urgency episodes, urgency urinary incontinence episodes, frequency-urgency sum, and all OAB Questionnaire scales and domains, but not nocturnal micturitions or nocturnal urgency episodes, were significantly greater with fesoterodine than placebo (all P <.05). Treatment differences in micturitions and frequency-urgency sum were significant by week 2 and in urgency urinary incontinence and urgency episodes by week 6. Significantly greater percentages of subjects taking fesoterodine had improved Patient Perception of Bladder Condition and Urgency Perception Scale scores at weeks 2, 6, and 12 (P <.05). Dry mouth (fesoterodine, 26%; placebo, 8%) and constipation (fesoterodine, 11%; placebo, 6%) were the most common adverse events. In both groups, 87% of the subjects completed the trial; 8% and 5% of the fesoterodine and placebo groups, respectively, discontinued because of an adverse event.

Flexible-dose fesoterodine was efficacious and generally well tolerated for treatment of OAB symptoms.