Treatment of Overactive Bladder with Once-daily Extended-release Tolterodine or Oxybutynin: The Antimuscarinic Clinical Effectiveness Trial (ACET)

Abstract

SummaryTreatment with the antimuscarinic agents tolterodine and oxybutynin is the mainstay of therapy for overactive bladder, a chronic and debilitating condition characterized by urinary urgency with or without urge incontinence, usually in combination with urinary frequency and nocturia. This study consisted of two trials; in one, patients with overactive bladder were randomized to 8 weeks of open-label treatment with either 2 mg or 4 mg of once-daily extended-release tolterodine (TER), and in the other to 5 mg or 10 mg of extended-release oxybutynin (OER). The study protocol and design were identical for the two trials and site selection ensured that there was no bias in either trial for the tendency of investigators to prescribe one drug rather than the other, or for geographical location. A total of 1289 patients were enrolled, 669 in the tolterodine trial (TER 2 mg, n = 333; TER 4 mg, n = 336) and 620 in the oxybutynin trial (OER 5 mg, n = 313; OER 10 mg, n = 307). Fewer patients prematurely withdre...