A nicotine vaccine could give smokers some needed help in quitting, phase 2 trial results suggest. The highest dose of the vaccine produced antibodies against nicotine and caused higher cessation rates than a placebo, researchers reported at the American Heart Association 2007 Scientific Sessions in Orlando, Fla.
In the trial, 301 people who smoked at least 15 cigarettes a day (average, 24) were randomly selected to receive either the nicotine vaccine or a placebo. Those who received the vaccine got either four or five injections of either 200 mcg or 400 mcg over 26 weeks. Smoking cessation efforts began 1 week after the second injection.
At 12 months, quit rates were 16% for those who got the vaccine and 6% for those who got a placebo. Quit rates were highest for those who received five injections of the higher-dose vaccine; they also achieved the highest antibody titers.
Researchers say that the vaccine achieves quit rates that are in line with other smoking cessation aids, including nicotine patches and bupropion. However, other smoking cessation aids work on the brain to alter the nicotine addiction process. The vaccine, being developed by Nabi Biopharmaceuticals as NicVAX (nicotine conjugate vaccine), targets the nicotine itself.
In general, people tolerated the vaccine well. Adverse reactions were mild and included reactions at the injection site, fever, and aches. A larger trial involving several hundred people is needed before the vaccine can be marketed.