Nicotine vaccine delays the drug's effects in mice

Smokers who want to quit have a few tools to turn to. There are nicotine patches and gum, but they're not always effective. There are drugs that target nicotinic acetylcholine receptors, but these come with a risk for nasty side effects such as hallucinations, depression and severe mood swings.

Vaccines that target the nicotine molecule itself would be an alternate strategy. Two candidates advanced into clinical trials recently. They ultimately failed -- but not without first yielding clues as to how scientists could improve upon them. Individuals in the trials who produced the highest levels of anti-nicotine antibodies were more likely to abstain from smoking for over six months. Kim D. Janda and colleagues wanted to build on this lead.

The researchers designed a new vaccine that could increase the number of antibodies that could attach to nicotine molecules. Testing in mice found that the vaccine delayed the effects of nicotine within the first 10 minutes after injection. They also found that treated mice had lower concentrations of nicotine in their brains, which is where the drug exerts its effects. The researchers say future efforts will focus on further refining the vaccine formula to get it ready for potential clinical trials.