Efficacy and safety of the noradrenaline reuptake inhibitor, TAS‐303, in women with stress urinary incontinence: Results of a double‐blind, randomized, placebo‐controlled, early phase II trial

Objective To carry out an exploratory assessment of the efficacy and safety of TAS-303, a noradrenaline reuptake inhibitor, in women with stress urinary incontinence. Methods In a double-blind, placebo-controlled, early phase II study, women with stress urinary incontinence and stress urinary incontinence-predominant mixed urinary incontinence were randomized to a placebo or TAS-303 (3 or 6 mg) once daily for 8 weeks. The main efficacy end-points were mean percentage change in incontinence episode frequency per 24 h from baseline to week 8 (the primary end-point) and week 4. Results At week 8, the mean percentage change in incontinence episode frequency per 24 h was -34.73% in the TAS-303 3 mg group, -35.41% in the TAS-303 6 mg group and -28.07% in the placebo group (differences vs placebo, not significant). In patients with stress urinary incontinence, or incontinence episode frequency less than two episodes per 24 h at baseline, TAS-303 significantly reduced incontinence episode frequency versus placebo after 4 weeks; some secondary end-points also showed a tendency to improve in the same subgroups. No serious adverse events (e.g. central nervous system or cardiovascular effects) were observed; TAS-303 was well tolerated and had a favorable safety profile. Conclusion These findings suggest that TAS-303 is effective for improving stress urinary incontinence symptoms in some subgroups of patients with stress urinary incontinence. Therefore, further research is warranted.