OnabotulinumtoxinA (onaBoNT-A) Versus Oral Oxybutynin ER

Overactive bladder is a condition associated with symptoms of feeling the urge to urinate, urinating often, and may or may not be accompanied by leakage of urine. A patient who has a spinal cord injury (SCI) often suffers from an overactive bladder which often leads to urinary incontinence (UI - an unwanted leakage of urine). OnaBoNT-A bladder injections have been studied in clinical research trials. The results have shown an improvement in urinary symptoms by reducing how often urine leakage occurs and by increasing the amount of urine the bladder can hold. This purpose of this clinical trial is to see if onaBoNT-A is safe and effective when injected into the bladder for the treatment of UI and if it works better than a drug that is taken by mouth. A second purpose of the study is to perform research tests on the urine samples provided by the volunteers. Urine presents a rich source of information for bladder diseases and the biomarkers (the chemical make-up of the urine cells) will be examined to learn if there are yet undiscovered reasons for urinary diseases. These tests would be very beneficial because the results would lead to better treatment of the urinary diseases. Volunteers will be randomized to either: ARM 1: onaBoNT-A 200 U bladder injection and placebo oral capsule daily or ARM 2: Placebo bladder injection (saline) and oxybutynin ER 10mg capsule twice a day. The treatments are onaBoNT-A bladder injection and a placebo oral capsule once a day or placebo bladder injection and oxybutynin ER (like Ditropan) capsule twice a day. Placebo contains no active medicine. Participation in this study will be about 6-7 months and involve 5 visits to the clinic. The risks of bladder onaBoNT-A