An Open Label Study of Solifenacin Succinate (VESIcare®) for the Treatment of Overactive Bladder in Parkinson’s Disease

Objective: To evaluate the safety and efficacy of solifenacin succinate (VESIcare®) in Parkinson\u27s disease patients suffering from overactive bladder (OAB) in an open-label trial. Background: Urinary dysfunction is a commonly encountered non-motor feature in many idiopathic Parkinson\u27s disease (PD) patients. There are few controlled trials that have evaluated medical management of urinary dysfunction in PD. Methods: Following a double-blind, randomized, placebo-controlled trial that evaluated the efficacy of solifenacin succinate (VESIcare®) in 28 PD patients with OAB, patients were invited to participate in a 12 week open-label study. All patients were given 5 mg of solifenacin succinate for 4 weeks; patients were allowed to remain on this dose or increase to 10 mg for an additional 4 weeks. Patients could continue to remain on this current dose, or reduce by 1 dose level until study endpoint (week 12). The primary outcome measure was the change in mean number of micturitions per 24 hour period from baseline to endpoint between active and placebo groups; secondary objectives included the change in the mean number of urinary incontinence episodes, the mean number of nocturia episodes per 24 hour period, urinary urgency as measured by the symptom severity score on The Patient Perception of Intensity of Urgency Scale (PPIUS), and the mean change in Patient Perception of Bladder Condition (PBC/PPBC). Results: Seventeen patients enrolled in the study (mean age=67.71±7.06 years), and 16 completed it (1 withdrew due to constipation). The mean number of urinary incontinence episodes per 24 hour period decreased significantly (1.33 ± 1.54 to 0.52 ± 1.01, p = 0.03), as did the number of nocturia episodes per 24 hour period (8.88 ± 3.37 to 1.64 ± 1.09, p=0.001), at a mean dose of 7.81mg/day. There was a trend noted for improvement in the PPIUS (p=0.09) as well. Other measures showed improvement, although not significantly. Other side effects included xerostomia which resolved after treatment was discontinued. Conclusions: In this open-label trial, treatment with solifenancin succinate (VESIcare®) led to a significant improvement in urinary incontinence and nocturia in PD patients, and was generally well tolerated. Further larger studies are needed to evaluate treatments for urinary dysfunction in PD patients