Prospective randomized controlled trial of extended-release oxybutynin chloride and tolterodine tartrate in the treatment of overactive bladder: Results of the OBJECT study

Objective: To compare the efficacy and tolerability of extended-release oxy butynin chloride and tolterodine tartrate at 12 weeks in participants with overactive bladder. Subjects and Methods: The OBJECT (Overactive Bladder: Judging Effective Con trol and Treatment) study was a prospective, randomized, double-blind, para llel-group study conducted between March and October 2000 at 37 US study si tes. Participants who had between 7 and 50 episodes of urge incontinence pe r week and 10 or more voids in 24 hours received extended-release oxybutyni n, 10 mg/d, or tolterodine, 2 mg twice daily. The outcome measures were the number of episodes of urge incontinence, total incontinence, and micturiti on frequency at 12 weeks adjusted for baseline. Results: A total of 315 women and 63 men were randomized and treated, and 3 32 participants (276 women, 56 men) completed the study. At the end of the study, extended-release oxybutynin was significantly more effective than to lterodine in each of the main outcome measures: weekly urge incontinence (P =.03), total incontinence (P=.02), and micturition frequency episodes (P=.0 2) adjusted for baseline. Both drugs improved symptoms of overactive bladde r significantly from baseline to the end of the study as assessed by the 3 main outcome measures (P<.001). Dry mouth, the most common adverse event, w as reported by 28.1% and 33.2% of participants taking extended-release oxyb utynin and tolterodine, respectively (P=.32), Rates of central nervous syst em and other adverse events were low and similar in both groups. Conclusions: Extended-release oxybutynin was more effective than tolterodin e as measured by end-of-study urge incontinence, total incontinence, and mi cturition frequency episodes, Both groups had similar rates of dry mouth an d other adverse events.