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Anti-Smoking Vaccine Effectively may Prevent Relapse in Smokers

It is hard to stop smoking, but you can do it! About 46.5 million Americans have quit smoking for good, and now there are more former smokers than current smokers. Maybe you've tried the nicotine patch or chewed nicotine gum. Maybe you've even tried the old-fashioned method and gone cold turkey, but you still keep lighting up. Quitting smoking is tough, but Anti-smoking vaccine could be another tool to help. It is estimated that about four million die each year because of cancer, heart disease and other smoking related illnesses.

Approximately half of otherwise healthy adults with invasive pneumococcal disease are cigarette smokers. Cigarette smoking is the strongest independent risk factor for invasive pneumococcal disease among immunocompetent, non elderly adults. Quitting smoking is the first and most essential step in treating COPD and slowing its progress. Many smoking cessation strategies, in fact, provide cigarette addicts with nicotine from sources other than tobacco--such as patches or gum. In many people who quit early, lung function stabilizes and eventually declines to about the same rate of nonsmokers in the same age group. In some people, lung function may even improve slightly after quitting.

Cigarette smoking causes 87 percent of lung cancer deaths. It is also responsible for many other cancers and health problems. These include lung disease, heart and blood vessel disease, stroke and cataracts. Women who smoke have a greater chance of certain pregnancy problems or having a baby die from sudden infant death syndrome (SIDS).

Scientific research review for anti-smoking vaccine:

In a study, more than twice as many people given five of the shots stopped smoking than those given fewer or phony shots, about 15 percent versus 6 percent after one year; according to American Heart Association conference. They received either four or five shots within six months. After another six months, researchers checked back with people. This development is the key for the field of smoking cessation research and could have a significant impact on how we treat patients with nicotine addiction.

About a third of smokers, or 4m people, try to quit each year, but the vast majority relapse within days or weeks and start to smoke again. The new vaccine is designed to "immunize" people who smoke against the nicotine "high." After getting the vaccine, the body produces antibodies that bind nicotine. The nicotine is prevented from leaving the blood and entering the brain. This limits the effect that nicotine has on the brain. Hopefully, without the nicotine effect, people won't enjoy smoking and will be able to quit.

Vaccine-induced antibodies that facilitate smoking cessation by blocking nicotine penetration into the brain also markedly reduce the drug's passage across the ex vivo human placenta, a NIDA-funded study has demonstrated. The finding suggests that maternal immunization during pregnancy may be safe and may to some extent protect the fetus from exposure to nicotine. This study supports the potential use of immunization," says Dr. Paul Pentel of the University of Minnesota Medical School, one of the investigators.
Some medicines that don't have nicotine have already been approved to help with quitting smoking. Bupropion (Zyban®), was first used as an antidepressant, and later approved by the FDA to help people quit smoking. Newer medicines also may help smokers (or former smokers) by stopping them from getting physical pleasure from smoking. One such medicine, varenicline (Chantix®), is FDA-approved for help with quitting. Varenicline is a pill taken twice a day.
A study by Celtic Pharma Development Services underlines the desire of smokers to seek more effective treatments to assist in helping them quit their addiction. There is a clear interest in the development of a successful vaccine and TA-NIC has the potential to be the leader in this field and a key driver in the treatment of nicotine addiction.
MMRF researchers have developed another type vaccine is to prevent nicotine from reaching the brain so as to reduce its effects and help keep people from becoming addicted. When injected in laboratory animals, the vaccine stimulates the immune system to produce proteins called antibodies that bind tightly to nicotine. The antibody-bound nicotine is too large to enter the brain, thereby preventing nicotine from producing its effects. The antibody-bound nicotine is eventually broken down to other harmless molecules.
Scientists at The Scripps Research Institute (TSRI) have designed a new way to make vaccines against drugs of abuse that could become a valuable tool for treating addiction by helping the body clear the drug from the bloodstream. They have taken an "immunopharmacotherapy" approach. That is, they have designed a drug that stimulates the immune system to clear the nicotine from the system. The new idea that they have developed is to take a chemical that resembles nicotine and use it to induce an active immune response. In this immune response, the body produces antibodies against nicotine that can neutralize it in the bloodstream. If a smoker later smokes a cigarette, the antibodies will clear the nicotine from the system before it reaches the brain.
Another study suggested that there was no evidence of withdrawal after vaccine injection or evidence that smokers increased smoking intensity to compensate for the reduced nicotine in the brain. Preliminary analysis shows that the highest dose of vaccine in participant smokers, who had not necessarily been interested in quitting, showed significantly higher rates of 30-day abstinence than placebo.

"Two additional human clinical trials with other nicotine vaccines have been conducted which showed similar safety profiles and higher abstinence rates in the highest nicotine vaccine dose or antibody level groups, and we hope to conduct further trials to confirm these results; said Dorothy Hatsukami, of the University of Minnesota and lead author of the study.

Most recently (November 2007) another successful result by Nabi Biopharmaceuticals and the Minnesota Medical Research Foundation suggested that NicVAX, Nabi's proprietary investigational vaccine being developed to treat nicotine addiction and prevent smoking relapse, is designed to stimulate the immune system to produce antibodies that bind to nicotine and prevent it from entering the brain. It is believed that these nicotine antibodies will act like a "sponge" soaking up nicotine as it circulates in the bloodstream and preventing it from reaching the brain. The positive stimulus in the brain that is normally caused by nicotine is no longer present, thereby eliminating the addictive properties of nicotine and, consequently, helping people to quit.

Clive Bates, director of Action on Smoking and Health, said: "A nicotine vaccine would be a profound development, which would effectively become one of the most important medicines in the response to cancer, lung and heart disease. If successful, the vaccine, known as TA-NIC, will help smokers to quit by stopping nicotine from reaching the brain, thereby preventing addiction.

"This development is key for the field of smoking cessation research and could have a significant impact on how we treat patients with nicotine addiction," said Rennard, who presented his findings to a meeting of the American Heart Association in Orlando, Florida.

These findings indicate the new vaccine is effective in reducing the behavioral effects of nicotine. An appropriately designed nicotine vaccine would be beneficial to those who do not respond to conventional nicotine treatments or who cannot tolerate the side effects associated with current pharmacotherapy. The most promising clinical application of human nicotine vaccine is likely to be in relapse prevention in abstinent smokers.

The vaccine could become part of a new generation of smoking cessation treatments. They attack dependency in the brain instead of just replacing the nicotine from cigarettes in a less harmful way, like the gum, lozenges, patches and nasal sprays sold today.

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