Nasal Spray May Provide New Answer for Erectile Dysfunction
Feb. 9, 2001 -- The latest treatment for erectile dysfunction comes in a thumb-sized atomizer that delivers enough of the drug to coat the nasal passages: spray, wait 15 minutes, and "you are good for about an hour," says Carl Spana, PhD, president and CEO of Palatin Technologies Inc., the Princeton, N.J.-based drug manufacturer.
The new drug, with the name PT-141, is about four years away from approval by the FDA, Spana tells WebMD. Because the drug works on the central nervous system to stimulate nerves to release molecules that cause tiny blood vessels in the penis to open, or dilate, "we expect PT-141 to work on all types of erectile dysfunction, regardless of the cause," says Spana.
Erectile dysfunction can be caused by a number of medical conditions, such as diabetes, high blood pressure, and high cholesterol, or by damage resulting from prostate cancer surgery. Besides these "organic" causes, the failure to achieve and/or maintain an erection can also be caused by psychogenic factors, says Spana. "We think this drug should work in all patients ... it will release signaling molecules that stimulate vasodilators to vasodilate by acting like a turbo-charged signal," he says.
If this new drug makes it through all the safety and effectiveness trials required for FDA approval, it could not only be a valuable treatment but also could put Spana's tiny company on the map. Right now, the company has only one approved drug -- a type of high-tech dye that allows radiologists to pinpoint the site of an infection.
When Viagra hit the market in 1998, it revolutionized the treatment of erectile dysfunction and added millions of dollars to the profit column of Pfizer, its maker. But it doesn't work for everyone, and that remaining need combined with the expectation of a financial bonanza continues to drive researchers to come up with new drugs.
Hunter Wessells, MD, an associate professor of urology at the University of Washington, says PT-141 has the potential to be "the ideal [erectile dysfunction] drug. The goal for therapy has always been to get a fast-acting, easy-to-administer drug with minimal side effects and good efficacy. A nasal spray also covers the on-demand aspect that has been applied to the concept of the ideal drug for treatment of [erectile dysfunction]."
Administering a drug through the nose is not a novel idea, says Wessells, who points out that this route is already used for Imitrex, a drug used to treat migraine headaches. He explains that drugs are quickly absorbed through the linings of the nasal passages and thus may enter the bloodstream even faster than drugs administered as pills.
While PT-141 is a central nervous system stimulator, Viagra works by helping to relax smooth muscle cells, which increases the blood flow to the penis and thus makes it easier to achieve and maintain an erection. Men are advised to take Viagra an hour before attempting sexual relations, and the drug's effect lasts for about 4 hours.