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Jab to stop addictions?Bupa investigative news - 16 September 2003 In the future vaccines may be used to fight addictions to drugs such as nicotine and cocaine, cancers such as prostate cancer and autoimmune diseases such as rheumatoid arthritis. Research into all these different areas were presented at the British Association Festival of Science in Salford, Manchester. But at what stage is the research, how successful are the vaccines and how long would it take before they become available? What were the headlines?The development of new vaccines hit the headlines following a day of talks at the British Association Festival of Science in Salford, Manchester. Among the key research projects that were covered in the media were:
Each research project received a different amount of coverage. The nicotine and cocaine addiction vaccines project appeared to have the most, and the autoimmune vaccine project gained the least. Examples of headlines in UK newspapers and websites included "Vaccine slows the progress of prostate cancer", "Now it's a jab to stop you smoking", "Vaccine could end drug abuse", "New wave of vaccines will help to fight addictions", and "Smoking vaccine that takes away the craving". What is the bigger picture?The details of the vaccine projects were presented at the British Association Festival of Science on 8th September. Three of the presentations focussed on the idea that vaccines could eventually be used to:
Vaccine for advanced prostate cancerThe Onyvax project at St. George's Hospital Medical School in London has been developing a vaccine to slow the progress of prostate cancer. They've discovered that immunising a patient with prostate cancer cells from other people with the disease causes the patient's immune system to reject the prostate cancer cells. The patient's immune system is now "sensitised" to prostate cancer cells and begins to attack and destroy the patient's own prostate cancer cells. Before the vaccination the immune system had ignored the tumour, leaving it to grow unchecked. An initial trial that vaccinated 28 men with hormone relapsed prostate cancer (HRPC) - an advanced form of the disease - has proved successful. The men were given immunisations of three laboratory-grown prostate cancer cells every month for one year. The progress of the disease was monitored by measuring the levels of prostate specific antigen (PSA), a marker for prostate cancer, in their blood. Dr. Mike Whelan, head of Onyvax, says the initial results are encouraging. "In around 30 per cent of our patients we have seen significant slowing of the rate of PSA release," he said. "This does not happen spontaneously in HRPC." Additionally, the patients treated this way went for 50 weeks without their cancer progressing, compared to an average of around 20 weeks for individuals who were not treated. This led Dr. Whelan to believe that "taken together, these results strongly suggest our vaccine is working well". Phase III of the clinical trials will occur within in the next 12 to 18 months and they hope to eventually extend their approach to other forms of cancer. Vaccines for nicotine and cocaine addictionThe work into vaccines for nicotine and cocaine addiction has been carried out by a British-based company called Xenova. The company had discovered that by making the body produce antibodies that specifically bind to drugs such as nicotine and cocaine, the effects of the drugs could be blocked. This works mainly by preventing the drugs from crossing into the brain and creating the "high" they normally produce. By preventing an addict from getting the "high" they crave, it is hoped that the vaccine will help them to stay free from drugs. Campbell Bunce, head of cellular immunology for Xenova explained, "Circulating antibodies should interfere with the usual transport of the drug to the brain by binding to the drug in the bloodstream, resulting in a complex that is too large to get across the barrier between brain and blood." In turn, he explained, "Exclusion from the brain will reduce or prevent the feeling of euphoria, which normally reinforces the drug taking habit. A reduction or absence of this trigger to smoke another cigarette, for example, should have an impact on overall behaviour, resulting in a reduced desire to smoke." So far the company have developed vaccines suitable for use with nicotine and cocaine, but they're not the only ones - companies in America and Switzerland are also investigating the possibility of nicotine vaccines. The next stage is to set up human trials to see if the strategy will really work and Campbell Bunce is hopeful they will. "It is essential that new therapeutics are developed to help treat drug dependence. The prospect of vaccinating against drugs of addiction is an interesting and novel approach that could provide addicts with additional means of effectively kicking their habit and staying quit," he added. Vaccine for autoimmune diseasesDr. Neil Williams and colleagues from the University of Bristol have been looking at using vaccines to treat autoimmune disorders, such as rheumatoid arthritis. They are trying to develop ways of "re-educating" a person's immune system to stop attacking the parts of the body that it is mistakenly seeking to destroy. In their laboratory work they've discovered that proteins taken from E. coli, a bacterium found in the gut and linked to cases of diarrhoea, has the ability to re-educate the immune system and turn off the inflammatory processes that cause autoimmune diseases such as rheumatoid arthritis. "We have shown that by altering these proteins we can use them to change the way in which the immune system behaves and, in particular, to stop it from damaging the body's own tissues in autoimmune disease. This provides an example of where vaccines may be used to turn off, rather than to turn on, the immune system," Dr. Williams said. "It represents an entirely new approach to treating important diseases in humans," he added. "Instead of managing the pain and inflammation, these new approaches can turn off the controls that are driving the damage. This is based on the ability to activate newly discovered regulatory process in the immune system." The process has so far been shown to work in animals and the first phase of clinical trials are due to begin in early 2004, with the backing of Hunter-Fleming Ltd. They hope to follow that soon after with a small test in humans.
What does this mean?Vaccine for advanced prostate cancerCommenting on the development of the prostate cancer vaccine, Christine Highley from the Prostate Cancer Charity, said, "It's looking very promising, precisely because of the group of patients in which it would be most relevant - those with advanced cancer who are coming to the end of standard prostate cancer treatment." "What happens at the moment," she explained, "is that the traditional treatment is hormone therapy. It works, but is limited in timing and the cancer can eventually become hormone resistant, and there isn't a whole lot that can be done then. "Some patients may get chemotherapy, but it's not chemotherapy for a cure in the way that patients with, for example, leukaemia would have it. It would be chemotherapy as palliative care, to simply keep things at bay for as long as possible, as you're really running out of options." But if the vaccine is introduced, it could change that situation. "So this is where, at the moment, the vaccine steps in, as it's another thing that can perhaps be used in patients, as long as it's well tolerated and won't have too much affect on quality of life," explained Christine. She added that, "We're quite familiar with the idea of Onyvax and the prostate cancer vaccine in general. As time's gone on there doesn't seem to be, as far as I'm aware, any great shocks coming out of it, such as nasty side-effects. It would be really good to get a vaccine to help men with the disease." Vaccines for nicotine and cocaine addictionNaj Dehlavi, spokesperson for the group Action on Smoking and Health (ASH) described the nicotine vaccine as an "interesting development" but said, "we're very aware that it's not out of its trial phase yet". At this stage, he believes it could be useful. "If it's safe and people use it successfully to give up smoking, which is a very deadly habit, then we see no harm in it and welcome it," he said. But, he added, it "shouldn't be seen as anything other than an extension on the existing nicotine replacement therapy (NRT) range." Vaccine for autoimmune diseasesNo-one was free to comment regarding the autoimmune disorder vaccine, but with 387,000 people in the UK suffering from rheumatoid arthritis, and 12,000 new cases being diagnosed each year, an extra method of relief from the pain and discomfort associated with the condition is likely to be welcomed.
What does this mean to me?All of the vaccines are still in their early stages, so it's likely to be a while until they become a reality, but they could become extra treatment options for the conditions concerned in the future. Some media coverage had suggested that the nicotine vaccine could even be used on children to prevent them from becoming addicted to smoking in the first place. But Naj Dehlavi was concerned at such an idea: "If people are going to use it in ways other than how the manufacturers intend, for example, inoculating children so they don't become smokers, then that is clearly wrong. That's not how we'd imagine the vaccine being used and wouldn't encourage it at all." According to ASH, current methods of NRT - such as gums and patches, should be the first port of call for smokers wishing to quit. If that's unsuccessful, the next stage is Zyban. Prostate cancer is the second most common male cancer, affecting mainly older men, and if caught early there's a good chance that it can be cured. Symptoms to watch for include:
Arthritis Care say the symptoms of rheumatoid arthritis are inflamed joints that become swollen, painful, and stiff. They admit that it can be hard to diagnose, but if you regularly experience similar symptoms, you should see your doctor. SummaryInvestigations and medical advances are constantly being explored and, as research into these vaccines suggest, future cures and treatments may eventually be delivered through a simple injection. Links for more information
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