A drug that acts in a very different way than Viagra could work for men whose erectile dysfunction is not helped by that popular medication, researchers have found.Viagra and its two newly marketed rivals, Levitra and Cialis, help men achieve erections by acting on the muscles of the penis, explained Dr. Jorge Brioni, a project leader in neuroscience research at Abbott Laboratories.The new medication, developed at Abbott and designated ABT-724, “targets the central mechanisms in the brain that control erectile dysfunction in humans,” Brioni said.The drug has been successful in animal tests and has moved into human trials. The full set of trials needed for marketing approval could take seven or eight years, said James P. Sullivan, regional vice president for neuroscience discovery research at Abbott.There is a need for a different approach because the Viagra-type drugs are not effective in a substantial percentage of men who try them, Sullivan said. “In particular, the response rate is not as great as we would like in patient with diabetes,” he said.ABT-724 is a variation of a drug called apomorphine, which acts on brain receptors of a molecule called dopamine. Abbott markets apomorphine in Europe (but not in the United States) as a treatment for erectile dysfunction. Its success has been limited because it can cause nausea and vomiting.
