ASSESS-3: a randomised, double-blind, flexible-dose clinical trial of the efficacy and safety of oral sildenafil in the treatment of men with erectile dysfunction in Taiwan.

The efficacy and safety of sildenafil were evaluated in a randomised, double-blind, placebo-controlled, flexible-dose study in Taiwanese men aged 26 to 80 y with erectile dysfunction (ED) of broad-spectrum aetiology and more than 6 months' duration. A total of 236 patients were randomised at six medical centres in Taiwan to receive either sildenafil (50 mg initially increased if necessary to 100 mg or decreased to 25 mg depending on efficacy and toleration) (n=119) or matching placebo (n=117) taken on an 'as needed' basis 1 h prior to anticipated sexual activity for a period of 12 weeks. At the end of 12 weeks, the primary efficacy variables relating to the achievement and maintenance of erections sufficient for sexual intercourse, and the secondary efficacy variables, which included: (1) the five separate domains of sexual functioning of the IIEF (International Index of Erectile Function) scale, (2) the percentage of successful intercourse attempts; and (3) a global assessment of erections, were all statistically significantly improved by sildenafil in comparison with placebo (P<0.0001). Treatment-related adverse events occurred in 43.7% of patients receiving sildenafil and 18.8% receiving placebo. The most common adverse events with sildenafil were flushing, dizziness and headache (25.2, 6.7 and 5.9% of patients, respectively), and most were mild in nature. The efficacy and safety of sildenafil in the population of Taiwanese men appears similar to that reported in other studies in western populations.