New Vaccine for Nicotine Addiction

Weill Cornell Researchers Develop Novel Anti-Body Vaccine that Blocks Addictive Nicotine Chemicals from Reaching the Brain

Researchers at Weill Cornell Medical College have developed and successfully tested in mice an innovative vaccine to treat nicotine addiction.

In the journal Science Translational Medicine, the scientists describe how a single dose of their novel vaccine protects mice, over their lifetime, against nicotine addiction. The vaccine is designed to use the animal’s liver as a factory to continuously produce antibodies that gobble up nicotine the moment it enters the bloodstream, preventing the chemical from reaching the brain and even the heart.

“As far as we can see, the best way to treat chronic nicotine addiction from smoking is to have these Pacman-like antibodies on patrol, clearing the blood as needed before nicotine can have any biological effect,” says the study’s lead investigator, Dr. Ronald G. Crystal , chairman and professor of Genetic Medicine at Weill Cornell Medical College.

“Our vaccine allows the body to make its own monoclonal antibodies against nicotine, and in that way, develop a workable immunity,” Dr. Crystal says.

Previously tested nicotine vaccines have failed in clinical trials because they all directly deliver nicotine antibodies, which only last a few weeks and require repeated, expensive injections, Dr. Crystal says. Plus, this kind of impractical, passive vaccine has had inconsistent results, perhaps because the dose needed may be different for each person, especially if they start smoking again, he adds.

“While we have only tested mice to date, we are very hopeful that this kind of vaccine strategy can finally help the millions of smokers who have tried to stop, exhausting all the methods on the market today, but find their nicotine addiction to be strong enough to overcome these current approaches,” he says. Studies show that between 70 and 80 percent of smokers who try to quit light up again within six months, Dr. Crystal adds.

About 20 percent of adult Americans smoke, and while it is the 4,000 chemicals within the burning cigarette that causes the health problems associated with smoking — diseases that lead to one out of every five deaths in the U.S. — it is the nicotine within the tobacco that keeps the smoker hooked.

A New Kind of Vaccine

There are, in general, two kinds of vaccines. One is an active vaccine, like those used to protect humans against polio, the mumps, and so on. This kind of vaccine presents a bit of the foreign substance (a piece of virus, for example) to the immune system, which “sees” it and activates a lifetime immune response against the intruder. Since nicotine is a small molecule, it is not recognized by the immune system and cannot be built into an active vaccine.

The second type of vaccine is a passive vaccine, which delivers readymade antibodies to elicit an immune response. For example, the delivery of monoclonal (identically produced) antibodies that bind on to growth factor proteins on breast cancer cells shut down their activity.