EFFICACY AND SAFETY OF EXTENDED RELEASE OXYBUTYNIN FOR THE TREATMENT OF URGE INCONTINENCE: AN ANALYSIS OF DATA FROM 3 FLEXIBLE DOSING STUDIES

Abstract

We assessed the efficacy and safety of extended release (ER) oxybutynin at individualized doses for urge urinary incontinence. Data were combined from 3 flexible dosing studies of a total of 420 patients with urge urinary incontinence or mixed incontinence in whom ER oxybutynin dose adjustments were made to achieve the optimal balance between efficacy and tolerability, as judged by each participant. Individual doses were adjusted in 5 mg increments across a dose range of 5 to 30 mg daily. Efficacy was assessed during maintenance therapy using a 7-day diary. Data on 368 patients who completed dose adjustment were included in the analysis. In 47% of patients the preferred dose was greater than 10 mg daily. Individualized doses of ER oxybutynin produced a 79.3% decrease from baseline in the total of all incontinence episodes and an 83.2% decrease in urge episodes. Of patients 81% achieved a decrease of at least 70% in all incontinence episodes and 43% achieved total dryness. Moderate or severe dry mouth was reported by 23% of patients and it was cited as the cause for early withdrawal by 1.4% who completed dose adjustment. Therapy was well tolerated. In the pooled sample overall 6.7% of patients cited adverse events as the reason for discontinuing. Individualized dosing with ER oxybutynin was associated with highly effective and well tolerated control of urinary incontinence with more than 40% of patients achieving total dryness.