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Reliability of efficacy in men with erectile dysfunction treated with tadalafil once daily after initial success
R Shabsigh1, C Donatucci, R Costabile
1Maimonides Medical Center and Columbia University, New York, NY, USA. rshabsigh@maimonidesmed.org
Abstract:
The reliability of response to treatment is an important component of erectile dysfunction (ED) treatment. This study examined the reliability of tadalafil once daily (that is, successful attempts/total attempts) following initial successful intercourse. Data pooled from two randomized, double-blind, placebo-controlled trials of men with ED who received tadalafil 2.5 mg (N=96), tadalafil 5 mg (N=206) or placebo (N=148) once daily were analyzed to determine the first-attempt success rate and subsequent reliability of response. The first-attempt success rate (Sexual Encounter Profile question 3 (SEP3)) was significantly higher among men taking tadalafil 2.5 mg (45.7%) and 5 mg (55.2%) compared to placebo (28.5%; P<0.05 and P<0.001, respectively). Furthermore, following initial success, men taking tadalafil 5 mg had a significantly greater proportion of successful intercourse (SEP3) on subsequent attempts (85.9%, P<0.001) compared to men taking placebo (70.2%). Overall, men with ED taking tadalafil once daily experienced a high rate of reliability of efficacy.
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