Can the public access the vaccine now? How much does it cost if a person wants to use it, and is it covered by health insurance? How widespread do you anticipate use will become? Is it unique to Minnesota? The country?
Nicotine vaccines are still experimental and so are not available except for people enrolled in these studies. Studies are being done at the University of Minnesota but the investigators are not currently enrolling new subjects. There are 3 companies sponsoring clinical trials of nicotine vaccines. If these prove effective and safe, they might be marketed 2-3 years from now.
Why do you call it a vaccine? Is that the right term? Wouldn't a vaccine be something that people get so they don't start smoking? This is really great - keep up the cool work!
I agree that the term vaccine is a bit confusing. It is accurate in that a person is immunized with the nicotine vaccine to produce antibodies against a specific molecule, in this case nicotine. It is the way the nicotine vaccine is used that distinguishes it from most others. As you suggested, the vaccines all of us have received for infectious diseases are used for prevention. The nicotine vaccine is currently being tested for treatment, as an aid to help smokers quit. In theory it could also be used for prevention, but this is getting far ahead of the data and the kind of safety and efficacy testing that has been done so far.
Using a nicotine vaccine for prevention would be challenging because the levels of the antibodies produced gradually fall off over 3-6 months after the vaccine injection, so that repreated injections might be needed. This also differs from infectious disease vaccines, which are more convenient because the infectious agent is very similar in structure to the vaccine and exposure to the infectious agent itself boosts the antibody levels. The nicotine vaccine is quite different from nicotine itself because nicotine itself will not stimulate the immune system to make antibodies; it has to be linked to a large protein. Only the nicotine-protein molecule will stimulate antibody production, not just nicotine alone. This means that smoking would not boost the immune response, and a booster dose of vaccine would be needed periodically.
What other research does the Transdisciplinary Tobacco Use Research Center do? What is the big news coming out of TTURC right now?
The overall mission of the University of Minnesota TTURC is to reduce the harm posed by tobacco use through research, training, and communication. Toward that end, we are assessing methods to reduce tobacco toxin exposure in hopes of reducing disease and death in those smokers who are unwilling or unable to quit. Currently, our primary goals are to: a) Identify biological indicators of exposure to tobacco-related toxicants (such as cancer causing agents) and for measuring the tobacco-related toxicity (such as changes in DNA). We need these indicators to let us estimate the extent of exposure to toxic agents and damage that may be caused by the use of tobacco products and whether this damage or exposure to toxic agents can be reduced; b) Examine factors associated with individual differences in response to nicotine using animal models and human research data. We find individual differences in animals and humans in their response to nicotine. Some animals and humans are really sensitive to the effects of nicotine and others are not and we are trying to find out why; c) Test methods or approaches that would produce significant reductions in tobacco-related toxin exposure, and by testing these approaches, determine policies that would result in the least harm to public health. These approaches include testing different types of tobacco products or nicotine medicines; d) determine if a reduction in smoking can improve smoking cessation rates. We have also examined the extent of exposure to tobacco toxicant through secondhand exposure. The two most recent findings include the following:
1) Smokers reducing their cigarette intake do not necessarily experience a dramatic reduction in exposure to toxicants. The reason is because smokers who are reducing their cigarette intake smoke a lot harder on each of the cigarettes to achieve a higher level of nicotine, the addictive agent in cigarettes. Someone who reduces their cigarette intake to 5 cigarettes a day still receives 2 to 3 times more toxicants per cigarette than someone who has been a long term smoker of 5 cigarettes per day. Cigarette reduction should not be an end goal, but should serve only as a stepping stone towards cessation.
2) A significant number (46.5%) of Infants and children of mothers who smoked had detectable levels of cancer causing agents in their bodies. Therefore, banning smoking in the home would be important to protect our young (and adults) from toxic substances.
What did each of you study to get to the positions you are in now?
(Dr. Pentel) - I majored in biology in college and minored in chemistry. I went to medical school and, after that, did my residency training in internal medicine. I was intending at the time to practice medicinefull time, and this training gave me my clinical skills. Toward the end of this training I became interested in research and did a fellowship in Clinical Pharmacology (the science of understanding how drugs act and how to use medications effectively and safely) where I primarily did research and took courses in related areas like statistics. My work since then has always consisted of a mix of patient care, teaching and research. My original research interest was toxicology (drug overdose) but I then became interested in addiction and tobacco. I took no formal training to switch my research to this new area, but learned about it by reading and through colleagues I worked with.
One of the most influential and exciting parts of my education was getting experience in a research lab during high school and college. I did this through summer programs, or at times by contacting individual researchers or university departments in areas that interested me. These experiences allowed me to see what a research career would be like, and gave me a perspective that helped me in choosing courses and my career direction.
(Dr. Hatsukami) I received my undergraduate degree in psychology and my doctorate in clinical psychology. I then obtained a job as a professor at a University medical school. I was always interested in brain-behavior relationships. As a graduate student, I became interested in how drugs affect the brain and consequent behavior. Nicotine, in particular, was interesting to me because of the powerfully addictive nature of the drug, particularly when it is inhaled, and because of the dramatic effects the addiction to tobacco has on our health. Early in my career, I was interested in studying characteritics of a tobacco user's physical dependence to nicotine and then how we can treat this dependence. Although I still strongly believe that preventing and quitting tobacco use are the most effective ways of reducing death and disease associated with tobacco use, I also saw the need to explore potential methods of reducing health problems among those who continue to use tobacco. Therefore, I became interested in other toxic agents associated with tobacco use, such as cancer causing agents, and methods that can result in a significant reduction of these toxicants. (Visit our website www.tturc.umn.edu for more information.)
I agree with Dr. Pentel's staements about the importance of seeking research experience and also sitting around with people and brainstorming research ideas and how you go about studying a particular idea.
Are there any side effects to the vaccine? Or is it too early to know?
So far there have been no important side effects to the vaccine. It causes some discomfort at the injection site and some flu-like symptoms which last a day or two, like most other vaccines. The lack of side effects is probably because the antibodies produced by the vaccine bind only to nicotine, and not to any of the chemicals or structures normally present in the body. Nicotine is not normally present in the body; we get it only from smoking or using other tobacco products.
Even if nicotine is present in someone who is vaccinated (e.g. from smoking), the nicotine that is bound to antibody seems to have no additional toxicity or side effects.
As with all new drugs, we need to remember that the nicotine vaccine has been studied in only a relatively small number of subjects (several hundred). Continued monitoring of its safety will be needed during its development and, if it is approved for use, after that to see if there are less common side effects that we have not detected so far.
when will you vaccine be available to the public?
It is difficult to know when the vaccines will become available to the public. A number of studies need to be done to determine the best dose of the vaccine, how many doses should be given, and when they should be given. In addition, a large treament study needs to be conducted to determine the effectiveness of the vaccine compared to a placebo.
Would the vaccine work for people who used chewing tobacco?
Because the vaccine targets the nicotine molecule, this type of medication is likely to be effective with chewing tobacco. However, to date, no trials have been conducted with smokeless tobacco products. Typically, new medications are tested in smokers first (because of the higher rate of smoking compared to smokeless tobacco use in the U.S.), and then some researchers go on to test the effective medications for quitting smoking in smokeless tobacco users.
Have you found it to be more effective in people who smoke less or more frequently. Does the amount of time the person has been smoking affect the vaccine
These are very important questions but they have not been studied yet. In general, people who smoke less are more likely to quit regardless of how they do this (e.g. counseling, nicotine patches, or other medications) but many other factors are also involved. Whether "new" smokers might have an easier time quitting than those who have smoked for decades is not yet clear. Perhaps smokers could be treated more easily before their addiction is firmly established, but addiction occurs very quickly and even younger smokers who smoke irregularly often have the withdrawal symptoms and craving typical of nicotine addiction. Some studies are already looking at the use of nicotine replacement medications like the patch or gum in younger, less experienced smokers. If nicotine vaccines prove effective in long-term smokers, it would be interesting and important to see if they are also effective in newer smokers.
What other resources are there to help people quit smoking?
There are a number of resources that are available to help smokers quit smoking. They include: 1) your physician or health care provider; 2) some places of employment or health insurers provide cessation treatment; 3) the national quitline (1-877-448-7848) and 4) some states have their own quit line. I good resource to consult would be the National Cancer Insitute website www.cancer.gov/cancertopics/smoking.
Do your lungs recover after you quit smoking?
There are a number of ways that smoking injures the lungs.
Smoke irritates the airways, causing cough and sputum production. When this is persistent, it is called chronic bronchitis. Smokers who quit generally find that their cough improves greatly or goes away entirely. However, some smokers who quit may find that their cough gets temporarily worse when they quit because, as the tissues heal, they become more efficient at clearing out the accumulated debris. This usually last only a few weeks. Younger smokers also have a decrease in the exercise capacity which may impact their ability in sports. This seems to be reversible with quitting.
A longer duration of smoking can also lead to breakdown of lung tissue, which is not reversible. This causes shortness of breath, which can become severe, and is called emphysema. This kind of lung damage is most common in people who have been smoking for several decades, but can occasionally develop much earlier. There is no way of predicting whether someone is susceptible to this earlier onset. Emphysema is generally accompanied by chronic bronchitis, and the combination is called chronic obstructive pulmonary disease (COPD). When someone with COPD quits smoking, they often find that their shortness of breath decreases and their ability to exercise improves. This is due to improvement in the bronchitis component (irritation) , because the structural damage is permanent. This is why it is important to stop smoking as early as possible.
Smoking worsens asthma and may make it difficult or impossible to control with medications. Smoking, or even second hand smoke, also increases your chances of developing asthma. Quitting smoking makes asthma much easier to control.
Smoking also causes lung cancer. Lung cancer has a long incubation period, and generally occurs in older, long-term smokers, although some cases occur in smokers in their 30's or 40's. The longer you smoke, the greater the risk. When a smoker quits, their risk of lung cancer immediately starts to return toward that of a nonsmoker but this this is a slow process and it takes 10-15 years for the risk of lung cancer to approach that of a nonsmoker.
Why do poeple smoke?
Adolescents may initially smoke for social reasons. However, nicotine, when delivered through cigarette smoking, can be very addictive. When an individual smokes, nicotine enters the brain rapidly and at high levels. The faster a drug is delivered to the brain and at high concentrations, the greater the addiction potential of that drug. Once in the brain, nicotine targets specific receptors that lead to the release of a number of different chemicals in the brain. These chemicals allow nerve cells to communicate with each other. One of these chemicals or neurotransmitters is dopamine, which is also released by other drugs of abuse and considered to be the primary neurotransmitter that makes drugs addictive. Dopamine is released in a region of the brain that is associated with reward and motivation, that is, the mesolimbic region. The release of dopamine and other chemicals leads to feelings of pleasure, changes in mood and enhanced attention. These positive effects makes people want to smoke again. When people smoke cigarettes repeatedly, their brain adapts or changes to accommodate the delivery of nicotine to the brain or to the increase in neurotransmitters by increasing the number of nicotinic receptors in the brain or making receptors less sensitive to the chemicals. Because of these changes in the brain or “neuroadaptation,” when people quit smoking, they experience withdrawal symptoms. These symptoms include feeling irritable, anxious, depressed in mood and restless, and experiencing poor concentration, problems with sleep or weight gain. People smoke to avoid or relieve withdrawal symptoms and they smoke to pursue the pleasurable effects from smoking.
People smoke also for the sensory aspects of smoking and for behavioral reasons. There are a number of cues that are linked to smoking. These cues could include certain situations (e.g., after a meal, while on the telephone, a work break, with alcohol or coffee) or certain moods. Because there is a strong link that is developed between the cue and the effects from nicotine, people develop an urge to smoke when they are exposed to these cues.
These different aspects of smoking would mean that in treatment, smokers need to deal with their addiction to nicotine and with the behavioral aspects of smoking too.
Are there any uses for this type of vaccine to cure other addictions?
Similar vaccines are being tested for cocaine and methamphetamine addiction. The methamphetmaine vaccine has only been studied in animals, but a cocaine vaccine has compelted early clinical trials. The results are very preliminary but suggest some efficacy for decreasing cocaine use among those who are trying to stop.
I just heard on the radio an ad for laser treatment for tobacco addiction. Do you know how that works, or if it even does?
There is no evidence whatsoever that laser treatment is effective for smoking cessation. It is a variant of acupuncture, which is also ineffective.
The internet is full of advertising and promotions of "cures" for tobacco addiction which are actually worthless. Most involve herbal remedies, hynosis or acupncture. Most (but not all) of these are harmless, but it is unfortunate if people spend their time and money on them when there are many effective and well studied treatments available.
Effective treatments include counseling (ask your health care provdier, or get a referral from the Lung Association or Cancer Society) and medications; nicotine patches, gum, lozenge, inhaler or nasal spray; buproprion (trade name Zyban); and varenicline (trade name Chantix).
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