- Improved vaccine teaches body to clear up nicotine
- Latest nicotine vaccine may pass clinical trials in treating tobacco addiction
- Vaccine promises to prevent relapse into smoking after quitting by eliminating the "reward" feeling
A new vaccine against nicotine has proven to be more effective than its predecessors and could soon pass clinical trials. The team of scientists from The Scripps Research Institute, whose previous nicotine vaccine failed in clinical trials several years ago, have designed a more effective version which with the aim of helping smokers overcome their addiction.
Nicotine is the addictive ingredient in tobacco which makes it so difficult for smokers to stop. Researchers used nicotine-like molecules called haptens to create a vaccine which teaches the body to see nicotine as a foreign invader, and raise anti-nicotine antibodies. These antibodies would prevent nicotine from reaching the brain when the person uses tobacco.
Previous efforts to create a nicotine vaccine only worked in 30% of patients. The researchers believed they have identified the problem with the last version. Nicotine exists in nature as two different forms – a left-handed and a right-handed version – and the first vaccine was developed accordingly. Nicotine in tobacco, however, is 99% in the left-handed conformation.
Professor of Chemistry at Skripps, Kim Janda, said “This is a case where something very simple was overlooked.” In the new study, the vaccine was created using left-handed haptens, making it specialised against left-handed nicotine molecules.
Experiments in rats demonstrated that the new vaccine was much more effective in creating an immune response against nicotine found in tobacco. "This shows that future vaccines should target that left-handed version," said study author Jonathan Lockner, a research associate in Janda’s lab. "There might even be more effective haptens out there,” he adds.
As part of an anti-smoking treatment, the nicotine vaccine would still result in withdrawal symptoms, however a smoker would be unlikely to relapse as the reward system associated with smoking would be disabled. Smoking is the leading cause of at least six cancers, including lung and pancreatic cancer, as well as playing a major role in heart disease and emphysema.