New Impotence Drug Nears Approval

In the first real potential market rival to the blockbuster impotence drug Viagra, a federal advisory panel Monday recommended government approval of a new libido-enhancing drug for men that works on the brain rather than the sex organs.

Uprima, like Viagra, produces potentially serious side effects--among them fainting, vomiting, nausea, dizziness and low blood pressure--and likely will come with heavy-duty warnings if and when it reaches the marketplace.

The drug is manufactured by TAP Pharmaceuticals of Deerfield, Ill., a joint venture between Abbott Laboratories and Takeda Pharmaceuticals.

The compound, whose chemical name is apomorphine, stimulates the nerves in the brain that lead to improved erections, unlike Viagra, which acts by increasing blood flow to the penis.

The drug is dissolved under the tongue--unlike Viagra, which is swallowed--and has its peak effects within 45 minutes. But many men experienced erections within 10 minutes, according to TAP spokeswoman Kim Modory.

“This drug offers to bring spontaneity back into peoples’ sex lives,” she said.

But the drug can stay in the body for up to eight hours and panel members and Food and Drug Administration officials said that they found the side effects worrisome.

Some of the men involved in trials of the drug fainted or fell and hurt themselves, hitting their heads. One crashed his car into a fence, according to the FDA.

“There could be potentially fatal side effects, depending on the circumstances, if you are driving or operating machinery,” said Dr. Victor Raczkowski, deputy director of the agency’s office of drug evaluation 3, which oversees the regulation of reproductive and urological drug products.

“Between one and two out of 100 men had some fainting episodes,” he added.

The drug also can cause nausea and vomiting. In fact, in the early part of the century--before the 1938 act that required regulation of food and drugs--the compound was sold as an emetic--that is, a product that provokes vomiting.

There are also safety concerns about taking the drug with alcohol or with drugs to control high blood pressure, including nitrates, he said. Men taking nitrate-containing drugs are warned against taking Viagra.

But Modory said that TAP officials are confident that these problems can be overcome and the drug used safely. The company is also testing the drug on women to assess its effectiveness in enhancing their sexual pleasure.

“This is a step closer to approving the drug,” she said. “The side effects discussed in most cases were rare and we feel we can work through them.”

Officials from Pfizer Inc., the maker of Viagra--which enjoyed $1.03 billion in worldwide sales last year--said they are not concerned.

“The broad acceptance of Viagra among patients and doctors clearly speaks to its safety and effectiveness,” said Mariann Caprino, a spokeswoman for Pfizer. “We are looking forward to the competition.”

Viagra was approved in March 1998 as the first nonsurgical approach to the treatment of sexual dysfunction. It was an immediate hit, enjoying wildly popular sales.

It was easy to take and--unlike the only other available treatments--it did not require insertion or injection. Industry analysts at the time predicted that its sales could reach $500 million by 2003. The response has far surpassed those expectations.

But concerns soon arose about fatalities among men taking nitrate-containing drugs while using Viagra, and warnings about the potentially fatal drug interactions among heart patients were strengthened.

Up to 30 million men are believed to experience impotence at some time during their lives, particularly middle-aged and elderly men. Impotence can result from organic causes, such as diabetes, arteriosclerosis and prostate ailments or as a side effect of medication. It also can stem from psychological factors.

The drug appears to work by increasing levels of dopamine in the brain, a neurochemical that affects motor functions. It is the same chemical that patients with Parkinson’s disease lack--in fact, the drug has been approved in 12 countries for treatment of that disease, according to the FDA.