New Impotence Drugs Nearing Approval
Promise to Deliver Faster Erections for Longer
They presented the results of two studies in which more than 1,300 men took vardenafil or a placebo.
Thirty-nine percent of the men with severe erectile dysfunction were able to have sex after taking vardenafil. That's compared with only 2.5% of the men who took the placebo. Vardenafil worked for men with less severe erectile dysfunction, too. More than 70% of those with mild problems and about half of those with moderate problems had normal erections after taking it.
Vardenafil is more like Viagra than Cialis is. "I think the major advantages of vardenafil over [Viagra] are really not great," Murdock says. "They both appear to work about the same."
Of the two new drugs, vardenafil is closer to hitting the market. Murdock says he expects the FDA to approve it in August or September of this year. Cialis is likely to be approved in mid-2003, he says. That's because the FDA has asked to see more safety data on the drug. "They're very concerned about abuse of the drug," he says. "They want to see what would happen if people took this drug excessively for longer periods of time."
Pfizer, the company that makes Viagra, is playing it cool. Spokesman Geoff Cook says the company does not feel threatened by the competitors. "We actually think that new therapies coming into the marketplace is going to help grow the market," he says. Most men with erectile dysfunction have not sought treatment. "More products in the marketplace making noise, encouraging men to change their behavior and wake up to the condition, is going to drive them into the doctor's office."
Other studies to be presented this week hint at future possibilities for treating erectile dysfunction. Gene therapy is one.
Scientists at the Albert Einstein College of Medicine in New York injected rats with a human gene called maxi-K, which seemed to reverse the effects of aging on rats' penises. The smooth muscle tissue in the penis must relax to allow an erection, but aging decreases its ability to relax. If this gene were to have the same effect on humans it has on rats, it could become a new treatment for age-related erectile dysfunction.