Efficacy of solifenacin in patients with severe symptoms of overactive bladder: a pooled analysis

Background: The efficacy of antimuscarinic drug therapy in patients who have more severe symptoms of overactive bladder (CAB) at baseline has not been evaluated thoroughly. Objective: This analysis determined the effects of solifenacin in patients with severe CAB symptoms at baseline. Methods: All randomized, placebo-controlled phase III studies of solifenacin were pooled to determine the effects in patients with severe OAB symptoms at baseline. In these studies, patients were randomized to treatment with placebo or solifenacin 5 or 10 mg once daily. Baseline severity was defined according to the number of incontinence episodes/24 h, number of urgency episodes/24 h, and micturition frequency/24 h. The proportion of patients with restoration of continence, resolution of urgency, and normalization of micturition frequency at endpoint was determined. Mean change from baseline to endpoint in the number of episodes/24h for incontinence, urgency, and micturition, and in the volume voided/micturition were assessed. Comparisons of change from baseline to endpoint were done with analysis of covariance (ANCOVA), and comparisons of percentage change from baseline to endpoint were based on van Elteren's test. Results: Results from four multinational phase III studies of solifenacin with 2848 patients were pooled. The proportion of patients with restoration of continence, resolution of urgency, and normalization of micturition frequency at endpoint was significantly greater with solifenacin than with placebo among patients with severe OAB at baseline. Solifenacin 5 and 10 mg were significantly (p < 0.05) more effective than placebo for reductions in the number of episodes of incontinence, urgency, and micturition, and for the increase in volume voided/ micturition among most subgroups of patients who were highly symptomatic at baseline (incontinence, urgency, or micturitions). Conclusion: Solifenacin was significantly more effective than placebo for patients with severe symptoms of CAR The significant and consistent response was observed for all endpoints with solifenacin 10 mg and for most endpoints with solifenacin 5 mg using different definitions of baseline disease severity, and supports the overall effectiveness of solifenacin in highly symptomatic patients.