What You Need To Know News

Some 35,000 men who participated in a major prostate cancer prevention trial are in the process of getting this disheartening—yet not entirely surprising—letter in the mail from the National Cancer Institute. The message: Vitamin E and selenium, long buzzed about for their supposed prostate cancer-fighting properties, have flopped. Flopped hard.

Officials announced this week that they had accumulated enough data to conclude that taking vitamin E or selenium, or even both together, does not prevent prostate cancer. In fact, vitamin E may even slightly increase the risk. Leaders of the trial, called the Selenium and Vitamin E Cancer Prevention Trial, were also concerned to find that slightly more cases of diabetes arose among men who took selenium. And though officials emphasized to reporters that the increased number of prostate cancer and diabetes cases may have been a coincidence, they aren’t taking any chances. That’s why participants are being told to stop taking the supplements.

I can’t say that I’m shocked. As I’ve mentioned in this blog before, we have been suffering from a certain degree of “vitamania” in the past few decades. Yes, some promising observational studies, which cannot prove cause and effect, done in the late 1980s and 1990s suggested that certain antioxidants, including vitamins A, C, and E, could protect against heart disease, cancer, and other maladies. But it turns out that those original antioxidant studies were misleading, a steady stream of more recent randomized studies that do prove cause and effect have shown. (If you’re interested, New Scientist slogs through some of the disappointing findings on beta carotene, vitamin E, and vitamin C.)

In most instances, the clinical trials have shown that vitamins have no effect and, in some, that they may even cause harm. Still, with the passage of a permissive 1994 law called the Dietary Supplement and Health Education Act that allows manufacturers to sell supplements without first proving that they provide health benefits, consumers have been left with a booming supplement industry quick to offer us a slew of supplements for any and every ailment.
Source: http://www.usnews.com/blogs/on-men/2008/10/28/prostate-cancer-throws-vitamin-e-another-strike.html

A WEIGHT-loss pill waiting for approval for use in Australia has been suspended in Europe over concerns it may be linked to suicide and sudden death.

Health officials said the risk of side effects from the drug, Acomplia, outweighed its benefits.

Seven deaths, including a suicide, have been associated with the anti-obesity treatment, which also doubles the risk of psychiatric disorders, the Daily Mail reported today.

Around 2500 adverse reactions have been reported by British patients since it became available to private buyers two years ago.

US authorities refused to approve the drug amid mounting scientific evidence of the suicide dangers.
Acomplia was approved four months ago as a “last-chance” solution on the National Health Service by the British Government’s health body, the National Institute for Health and Clinical Excellence.
Although warnings on packets about the higher risk of depression, anxiety and other serious side effects were strengthened, the European Medicines Agency (EMA) has decided to suspend the medicines licence for Acomplia because the “benefits no longer outweigh its risks”, the Daily Mail said.

‘New data from post-marketing experience and ongoing clinical trials indicated that serious psychiatric disorders may be more common than in the clinical trials.’

Acomplia, also known as rimonabant, was licensed for obese people, as well as overweight patients who have type 2 diabetes or cholesterol problems.

The drug’s maker, Sanofi-aventis, said”: The company will comply with the European authorities request to temporarily suspend the marketing authorisation of Acomplia in obese and overweight patients and will make every effort to actively support patients and health care professionals in this process.”

Sanofi-aventis has applied to the Australian Therapeutic Goods Administration to sell the drug here and a decision was expected early next year.

A spokeswoman for Sanofi-aventis in Australia said those plans were now on hold pending the final decision of the EMA after it receives more data from the company.
Source: http://www.news.com.au/story/0,23599,24545607-1702,00.html

Analysis of data from several phase I and II clinical trials of a new cancer vaccine has shown it is capable of eliciting an immune response in most patients with bowel, kidney and prostate cancer, and that it may provide clinical benefit.

In a news briefing at the 20th EORTC-NCI-AACR Symposium on Molecular Targets and Cancer Therapeutics in Geneva (Thursday 23 October), Dr Richard Harrop, vice-president of clinical immunology at Oxford BioMedica, a UK-based biotechnology company – said: “Our exploratory analyses of data from nine different trials of TroVax® demonstrate significant associations between immune responses and overall survival in patients with colorectal cancer, renal cancer and prostate cancer.

“While it is essential that these observations are confirmed in large, randomised studies, collectively the data suggest that TroVax could provide some clinical benefit to cancer patients. In addition, the data show the vaccine is well tolerated by patients.”

TroVax is made up of a modified virus (Modified Vaccinia Ankara (MVA)), which acts as a vehicle to transport a second component, a gene that produces an antigen that is present in most solid tumours, called 5T4. TroVax is injected into patients whose solid tumours have the 5T4 tumour antigen present, so that the vaccine can trigger the body’s natural immune responses to mobilise against 5T4.

“The virus acts as both a ‘vehicle’ to deliver the 5T4 antigen and as an ‘adjuvant’, which helps to ensure we stimulate a strong immune response to the 5T4 antigen,” explained Dr Harrop. “Antibody and cellular responses can occur in response to both the viral vector (MVA) and to the 5T4 antigen.”

The analysis, presented at the symposium in Geneva, looked at data from 189 patients who had taken part in nine trials of TroVax in the UK and USA. The patients received an average of five injections (with a range of 1-12), and it was well tolerated by patients when given either on its own or in combination with other anti-cancer treatments. Of 180 patients tested for antibody responses after vaccination, 88% (159) showed positive responses to 5T4 and 98% (176) showed positive responses to MVA.

The highest levels of antibody responses were detected after an average of two vaccinations for the MVA part of the vaccine and after four for 5T4. Dr Harrop said: “This was expected because MVA is a foreign virus which the immune system responds to more quickly than to a ’self antigen’ such as 5T4.”

He continued: “When looking at the results from all the trials (colorectal, renal and prostate cancer patients), the magnitude of the 5T4-specific antibody response was associated with increased patient survival. Indeed, a doubling of the average number of antibodies in the patients between the first and third injections was associated with a reduction in the relative risk of death of 17%. This effect was strongest in colorectal cancer patients.

“Both the magnitude and the frequency of immune responses elicited against our tumour target (5T4) are exceptionally high and could be considered ‘best in class’. Since cancer vaccines rely on the induction of immune responses to be able to work, this is a very important attribute of TroVax.”

Cancer vaccines have been criticised in recent years because they usually fail to live up to their early promise. Apart from the vaccines against cervical cancer and Oncophage™ (vitespen, approved in Russia for the treatment of kidney cancer), there are no other licensed cancer vaccines. Dr Harrop said there were a number of reasons for this, which included the tools used to assess efficacy, the fact that vaccines on their own are more likely to slow disease progression or clear small tumours rather than cause large reductions in tumour burdens, and the fact that they are probably more likely to work in patients with early stage disease but have to be tested in patients with late stage cancer and large tumour burdens.

“To run a trial in patients with early-stage disease is extremely time-consuming and costly and therefore impossible for most small biotech companies. We are fortunate in this matter in that we have backing from a UK consortium (QUASAR) and our partner sanofi-aventis to run a large (over 3000 patients) phase III study in early stage colon cancer patients. Such a large study would normally be out of the question for a company of our size and is a great opportunity to investigate whether there is a survival advantage in patients treated with TroVax,” he said.

“At this stage we can say that the fact we have been able to identify correlations between the anti-tumour (5T4) immune response and clinical benefit (e.g. increased time to disease progression or increased patient survival) in multiple independent trials for several cancers is very encouraging. It gives a strong indication that the immune response we are inducing with TroVax appears to be doing something which is associated with benefit to the patient.”

In addition to the phase III trial in early stage colon cancer patients, the effect of TroVax is being monitored in a current phase III trial of 733 kidney cancer patients. Although a review by the independent Data Safety Monitoring Board (DSMB) in July noted that this study would not meet its pre-defined primary endpoint (overall survival) the DSMB supported continuation of follow-up of the patients.

“We are very hopeful that the ongoing phase III trial in kidney cancer and two planned studies in metastatic colorectal and early stage colon cancer respectively will provide an opportunity to demonstrate that TroVax can provide clinical benefit to patients without the often severe side-effects which are associated with many cancer therapeutics,” concluded Dr Harrop.
Source: http://www.sciencedaily.com/releases/2008/10/081023195220.htm

Wolfing down your food and eating until your seams are straining could double your risk of becoming overweight, Japanese researchers have found.

A study published in the British Medical Journal this week reveals that men and women who eat rapidly or eat until they are full are twice as likely to be overweight compared to people who eat more sensibly.

People who both eat quickly and eat too much are around three times as likely to be overweight, the researchers found.

They also report that the link between the eating behaviour and overweight remains the same no matter what the actual calorie intake from the food itself.

Co-author of an accompanying editorial, Dr Elizabeth Denney-Wilson, says the study provides more evidence that eating behaviours themselves are a significant promoter of ‘positive energy balance’ - the situation where energy intake is higher than energy spent - and may be contributing to the current obesity epidemic.

Part of the problem is that humans are not very good at knowing when to stop eating, says Denney-Wilson, research fellow at the Centre for Primary Health Care and Equity, University of New South Wales in Sydney.

“Humans are not good at using the cues from their bodies to determine when they’re full,” she says.

“They’re much more likely to use visual cues so if they have a great big portion in front of them they’re likely to eat the lot.”

The researchers suggest these unhealthy eating habits are not necessarily there from birth but instead appear to be learned, or taught.

“It is possible to have children self-regulate their energy intake, and we certainly see that with breast-fed babies who are clearly regulating their own energy intake because they are able to determine when they are full.”

However the dramatic increase in portion sizes and unprecedented availability of food makes it harder to exercise restraint, the researchers say.

“Until recently there was just never more food than people needed, so it was impossible to eat beyond satiety,” says Denney-Wilson.

She says it is possible to overcome this urge to overeat by learning to recognise the cues of fullness, something that health professionals could work on with their patients.

While this is not the first study to suggest a link between fast eating and overweight, Denney-Wilson says the cultural context of the study is particularly surprising, as the Japanese are generally considered to be more ’social’ eaters compared to those in Western nations, where fast food is so readily available and eaten.

Source: http://www.abc.net.au/science/articles/2008/10/22/2398053.htm?site=science&topic=latest