Do predictive parameters exist for therapy with duloxetine in women with stress urinary incontinence?
To assess the impact of duloxetine dose escalation on tolerability and efficacy, 516 women with stress urinary incontinence were randomized to receive placebo or duloxetine in one of three regimens: 40 mg BID for 8 weeks, 40 mg QD for 2 weeks escalating to 40 mg BID for 6 weeks or 20 mg BID for 2 weeks escalating to 40 mg BID for 6 weeks. A non-inferiority analysis confirmed that the 20 mg BID starting dose was significantly better than the other two duloxetine regimens for nausea reduction (16.5% vs 25.2% and 29.4%). There were also significant differences in the discontinuation rates (7.5% vs 11.8% and 16.2%). The efficacy after 4 weeks was significantly better with duloxetine than with placebo. Starting duloxetine at 20 mg BID for 2 weeks before increasing to 40 mg BID significantly improved tolerability but did not impact duloxetine efficacy after all the subjects had been on 40 mg BID for at least 2 weeks.