Doctors Test Anti-Smoking Vaccine

University of Wisconsin Center for Tobacco Research and Intervention study participant Mario Musachia, 75, gets an injection from Donna Muehlenbruch Monday, July 10, 2006, in Madison, Wis. Doctors are testing a radical new way to help smokers quit: a shot that "immunizes" them against the nicotine rush. (AP Photo/Morry Gash) (Morry Gash - AP)

Of the more than 48 million smokers in the United States, 40 percent each year make a serious attempt to quit, but fewer than 5 percent succeed long-term. Nicotine replacement products combined with counseling can double that rate, but most quitters don't try them. Two-thirds go back to smoking within a month.

"When they have that first cigarette, if they really enjoy it, they're at high risk of relapse. If you can make that cigarette not so good, you've really got something," Vocci said.

The possibility that a simple shot could do this is what lured Musachia to the Center for Tobacco Research and Intervention on the fringes of the University of Wisconsin-Madison campus earlier this month. He has tried many ways to quit but still smokes.

"I'm sick of it. I'm surprised I've lived this long," said the 75-year-old man. "My kids _ they carry on like 2-year-olds when I smoke around them. My animals run and hide."

He and other participants will get four or five shots, either four or six weeks apart, and will be studied for a year. Two-thirds will get the vaccine; the others, dummy shots. Neither they nor the doctors will know who got what until the study ends.

They also will get counseling and must set a quit date, usually around the second shot, because the first shot is just meant to "prime" the immune system. Subsequent doses make it produce antibodies, which latch onto nicotine in the bloodstream and keep it from crossing the blood-brain barrier and getting into the brain where it maintains the addiction.

"They won't get the rush, the reward," but the small amount still getting in "we think is an advantage," because it should lessen withdrawal symptoms, said Dr. Henrik Rasmussen, Nabi's chief medical officer.

The antibodies should remain in the system for up to a year; booster shots may be needed after that, but this needs more study, Rasmussen said.

The new drugs come at a time of heightened attention to helping smokers quit. Last month, the National Institutes of Health held a conference to review the scientific evidence for what smoking cessation techniques work.

Earlier this month, two large scientific conferences were held in Washington, D.C., on the topic.

Research money has increased because of tobacco lawsuit settlements, and insurers increasingly see the health burden of smoking and will pay for cessation treatments that work, said Douglas Jorenby, the psychologist who heads the NicVax study in Madison.

Smokers also are demanding better results than those afforded by traditional nicotine replacement tools. Their desperation sometimes makes them prey to quacks.