A jab that will cure high blood pressureBy FIONA MacRAE
Last updated at 19:49 13 May 2007
British scientists have developed a vaccine to control high blood pressure which could save tens of thousands of lives a year in the UK alone.
Based on a protein found in limpets, it would need a course of just three jabs, with a booster every six months.
High blood pressure, which affects a third of all adults, doubles the risk of dying from heart disease or stroke and is blamed for 60,000 deaths a year in Britain.
It is currently treated with pills, but they can cause side-effects and some patients simply stop taking them.
Now the Cheshire-based drug firm Protherics says its vaccine will make it much easier for people to control their blood pressure.
"Improving compliance in this way could save thousands from life-threatening complications such as heart attack or stroke," said the company's Dr Andrew Heath.
The jab, which has been successfully tested on people, uses the limpet protein to attack a hormone called angiotensin, which is produced by the liver.
Angiotensin raises blood pressure by narrowing arteries. The vaccine, however, turns the body's immune system against the hormone.
Protherics is planning trials of an improved version of the jab, which is ten times more effective at stimulating the immune system than its original formula.
People who have tried it have suffered few side-effects, although one in ten did complain of a brief, flu-like illness.
A successful jab would guarantee its manufacturers a healthy share of the £12 billion spent around the world annually on blood pressure medicines.
Ideally, patients would be given an initial course of three injections, with a week or fortnight between each jab.
A booster shot every six months, or even once a year, would keep blood pressure low.
The Swiss firm Cytos Biotechnology is developing a similar vaccine which uses an empty virus shell to spur the immune system into action.
Zurich-based Cytos, which is also developing anti-smoking, obesity and flu vaccines, has already shown that its jab is effective at lowering blood pressure.
But the reduction was less than that achieved by tablets already available on prescription. Further trials are due to later this year.
British heart doctors welcomed news of the jab, which should be on the market within five years.
Professor Graham Mac-Gregor of the Blood Pressure Association said: "Raised blood pressure is the most important cause of death from strokes and heart attacks in the UK.
"If you have to take blood pressure tablets, you have to take them for the rest of your life and some people find that difficult.
"Finding other ways and better ways of trying to lower blood pressure without side- effects would be very much welcome."
Dr Mike Knapton of the British Heart Foundation said: "More than one in five heart attacks in Western Europe is caused by a history of high blood pressure. A vaccine is an interesting approach but more research will be needed."
It is not known how much the vaccines will cost but they are not expected to be much more expensive than current blood pressure tablets, some of which cost just a few pence a day.
Available privately at first, the jabs will not be offered on the NHS unless the Government's drugs rationing body, the National Institute for Clinical Excellence, decides their benefits outweigh the costs.
In time, the vaccine may be given to ward off problems in young men and women with a family history of heart disease.
Some blood pressure tablets already available work by targeting angiotensin, either by cutting production of the hormone or by stopping it from working properly.
But many people stop taking the daily tablets simply because there are no obvious signs that they are boosting their health.
Others give up after suffering side effects. Beta blockers, a major type of blood pressure pill, can cause fatigue, cold hands and feet, nausea, diarrhoea and impotence. They have also been linked to the risk of stroke.
Last month experts from the London School of Economics warned that the stress of modern life could be spawning an epidemic of heart disease, with half of Britons suffering from high blood pressure by 2025.
A growing reliance on fat and salt-laden fast food, coupled with long working hours, is blamed for sending blood pressure soaring.