Nasal Spray May Provide New Answer for Erectile Dysfunction
A few years ago, while teaching at the University of Arizona, Wessells conducted clinical studies of a "molecule that is similar to PT-141.That drug was administered with a subcutaneous injection," he says. "We studied 20 subjects with 39 administrations and found no serious side effects and no cardiovascular side effects." Some men who have heart disease can't take Viagra because it adversely enhances the affect of common heart drugs called nitrates.
Last year there was a great deal of excitement generated by another Viagra alternative called Uprima. That drug was recommended for FDA approval last April, but just as the FDA was poised to issue a final decision, the manufacturer, TAP Pharmaceuticals, withdrew the new drug application. Several vocal opponents of the drug said it caused fainting spells, which in one case caused a car accident when a man passed out at the wheel. The drug also causes nausea, and men were advised to avoid eating when taking the drug, which is given as a lozenge.
Martha McKennitt, a spokeswoman for TAP Pharmaceuticals, which is a joint venture of Abbott Laboratories of Abbott Park, Ill., and Takeda Chemical Industries of Japan, tells WebMD that the company "plans to meet this quarter with the FDA to determine when to resume the approval process" for Uprima.
"There is some overlap of the side effects profile between drugs like PT-141 and [Uprima], at least as far as nausea," says Wessells. But he says that the effects do not appear as pronounced.
Although Wessells tells WebMD that he is not directly involved in the studies of PT-141, Spana says that Wessells serves on Palatin's clinical advisory board.
PT-141 is now being tested in safety trials in healthy men. Spana expects to complete those studies by May and then begin dose trials in 60 men with erectile dysfunction. Those studies will be used to determine the most effective dose of the drug, he says. When the dose studies are complete, hopefully later this year, the company plans to "enter pivotal studies by the second quarter of 2002," says Spana. Pivotal studies, also called phase 3 trials, are the final studies required by the FDA before a drug can be considered for approval. "If all goes well," he says, "we will have the FDA approval by late 2003 or early 2004."