Treatment: NicVAX
Maker: Nabi Biopharmaceuticals
Stage: Phase IIb began in May 2006, results expected April or May 2007.

Why It Matters

Tobacco use is the leading preventable cause of death in the United States. According to the CDC, an estimated 70 percent of smokers want to quit, but each year only 2.5 percent succeed in quitting permanently.

How It Works

NicVAX is designed to vaccinate the body against nicotine. Funded in part by the National Institute on Drug Abuse (NIDA), it combines nicotine with a bacterial protein that causes an immune response. (The protein has been rendered nontoxic via genetic modification.) Once vaccinated, a person generates antibodies against nicotine, preventing it from reaching the brain, where its "rush" can reinforce and maintain addiction.

In its phase II trial, "NicVAX led to a 33 to 40 percent quit rate from smoking, compared with a 9 percent effect for the placebo," notes Jamie Biswas at NIDA. Nabi Biopharmaceuticals is currently identifying the optimal dose level and schedule for the vaccine--so far they are looking at three or four injections over a six-week period, which should protect against nicotine for 12 to 18 months. "Twelve months is the key--if a person can get to that, the chances are 75 to 85 percent they'll remain smoke-free," says Nabi spokesman Thomas Rathjen.

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