ORLANDO, May 15: An experimental vaccine against nicotine helped smokers kick the habit, Swiss researchers reported on Saturday. Larger tests are needed but the test of heavy smokers suggested that 40 per cent were able to quit smoking for nearly six months after receiving the vaccine, the researchers said.

Zurich-based Cytos Biotechnology AG plans phase III trials aimed at showing the vaccine is not only safe but works, and is aiming to get it on the market by 2010, Cytos Chief Executive Dr. Wolfgang Renner said.

Speaking to a meeting of the American Society of Clinical Oncology, Dr. Jacques Cornuz of University Hospital Lausanne said the vaccine was based on a bacteriophage, a type of virus that attacks bacteria.

Cytos designed a vaccine that uses part of a protein from the virus, genetically engineered to attract an immune system response to nicotine. Patients who get the vaccine generate antibodies that neutralize nicotine.

“They don’t feel that they have to take a cigarette to feel better,” Cornuz said in an interview.

For the Phase II study designed to show whether the vaccine is safe and can be tolerated, Cornuz’s team tested 341 smokers, of whom 239 also avoided using nicotine replacement therapy such as gum or patches.

Two-thirds of them got five doses of the vaccine, at varying doses, over four months. One-third got a placebo. Everyone was counselled about quitting smoking.—Reuters