A new effective nicotine vaccine to help smokers and drug addicts overcome their addiction has been discovered by a team of researchers. The team has proved that the structures of molecules used in vaccines are critical.
According to researcher Kim Janda, Professor of chemistry at The Scripps Research Institute (TSRI), the “study provides new hope that one could make a nicotine vaccine that succeeds in clinical trials.”
With an effective nicotine vaccine, people may be less motivated to relapse because the brain’s reward system could no longer react to nicotine. As per reports, smoking is the leading cause of eight types of cancer, including lung cancer and fast-moving pancreatic cancer.
The scientists from TSRI in the US first found the reason why a promising nicotine vaccine failed in clinical trials a few years ago. The problem with the previous nicotine vaccine, which only worked in 30 percent of patients, was that it did not single out the most common form of nicotine for attack.
Nicotine has two forms that look like mirror images of each other; one is a “right-handed” version and the other a “left-handed” version.
Even though 99 per cent of the nicotine found in tobacco is the left-handed version, the previous vaccine elicited antibodies against both.
In the new study, the researchers elicited a more robust antibody response by creating a vaccine from only left-handed nicotine derivatives called haptens.
To do this, they prepared haptens as a 50-50 mixture and as pure right-handed or pure left-handed versions of nicotine, so they could use the two versions together or separately. They have tested both versions and the 50-50 mix in rat models, injecting the rats three times over 42 days.
The researchers analysed blood from the three experimental groups and found that the left-handed hapten elicited a much more effective immune response.
“This shows that future vaccines should target that left-handed version,” said Jonathan Lockner, research associate in the Janda lab and first author of the new paper. “There might even be more effective haptens out there.”
The study was published in the Journal of Medicinal Chemistry.