June 5, 2001
New York - According to the results of a new phase III trial, IC351 (Cialis, Lilly Icos) was effective in treating erectile dysfunction in a majority of study participants.
"We are especially pleased by the results of this study, considering that Cialis demonstrated benefit in men with all degrees of ED, including those with severe cases," said Dr. Gerald Brock, of St. Joseph's Health Centre, Department of Urology, Ontario, Canada.
Of the 196 men who received IC351 in the placebo-controlled trial, more than 85% reported improved erections. In 2 additional clinical trials, men reported improved ability to achieve erections up to 24 hours after taking the drug. These data were presented at the 96th Annual Meeting of the American Urological Association in Anaheim, California.
The study examined the safety and efficacy of "on-demand" IC351 treatment in 196 men suffering from mild to severe ED. Men in the study were randomized to receive up to 20 mg of Cialis or placebo over a 12-week period. Men were free to take their study medication without restrictions on food or alcohol consumption and to have sex with their partners at the time of their choosing after each dose.
Study participants reported a 78% success rate for intercourse attempts recorded by men receiving the drug. Importantly, 63% of men treated with 20 mg of IC351 achieved an erectile function score experts consider "normal" for healthy men as measured by the International Index of Erectile Function (IIEF).
For the 10-mg dose, 92% of men reported improved erections, and 70% of intercourse attempts were successful. Forty-two percent of men taking the 10-mg dose achieved IIEF scores in the normal range. Fifty-four percent of patients receiving placebo in the study reported improved erections, while 43% of their attempts were successful. Twenty percent of men receiving placebo attained IIEF scores in the "normal" range.
Adverse effects in this study were mild to moderate, and their incidence diminished with continued treatment. The most commonly reported adverse effects were backaches, muscle aches, and upset stomach. There were no clinically significant changes in blood pressure, heart rate, electrocardiograms or laboratory tests attributable to treatment with IC351.
In the first of 2 other clinical trials conducted to evaluate duration of responsiveness, both of which were also presented at the AUA meeting, 61 men with mild to severe ED were randomized to receive IC351 10 mg or placebo. After taking IC351, the men were evaluated by RigiScan, a device for measuring the firmness and duration of erections, during exposure to visual sexual stimulation. Men in the IC351 group were significantly more successful in achieving erections than men in the placebo group at 24 hours after dose administration.
In the second trial, 223 men received IC351 up to 20 mg or placebo in a home-based study. The men were instructed to take the medication immediately before engaging in sexual activity and to use a stopwatch to record the elapsed time until they achieved an erection sufficient for successful intercourse. In this trial, the ability to achieve an erection after sexual stimulation was statistically superior in the group taking IC351 20 mg compared with the placebo group at 16 minutes postdose. Men receiving IC351 20 mg in this study also recorded statistically greater success at second sexual encounters than men on placebo for a period of up to 24 hours.
In these studies on duration of responsiveness, there were no serious adverse effects. The most common adverse effect reported was headache.
Erectile dysfunction is defined as the consistent inability to attain and maintain an erection sufficient for sexual intercourse. It affects an estimated 152 million men and their partners worldwide.