Smokers could one day be immunised against nicotine so they gain no pleasure from the habit, according to researchers in the US.
They have devised a vaccine that floods the body with an antibody to assault nicotine entering the body.
A study in mice, published in Science Translational Medicine, showed levels of the chemical in the brain were reduced by 85% after vaccination.
Years of research are still needed before it could be tested on people.
However, lead researcher Prof Ronald Crystal is convinced there will be benefits.
"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."