While a large number of products are currently available success rates for permanently giving up tobacco are varied. Figures from the American Lung Association suggest that relapse rates among smokers are as high as 90 per cent within a year of quitting. But the vaccine, which is injected, works by creating anti-bodies that bind to nicotine molecules, preventing them from passing the blood into the brain. If successful the vaccine could help prevent millions of smoking related deaths around the world.