ORLANDO, Fla., Nov 7 (Reuters) Cytos Biotechnology AG's vaccine to control high blood pressure is showing promise in early research, according to scientists who said it could free people from taking daily medication.
Many people with high blood pressure, also called hypertension, fail to keep it under control simply because they do not take their daily medicine.
Researchers led by Dr Juerg Nussberger of the University Hospital of the Canton of Vaud in Lausanne, Switzerland are exploring an approach that would involve periodic vaccinations rather than daily pills.
A small study presented at a meeting of the American Heart Association yesterday showed that the vaccine reduced blood pressure in people with mild to moderate hypertension.
In the study, 65 men and seven women with high blood pressure were injected with either a lower or higher dose of the vaccine or with a placebo. Average age was 51.
Those who got the vaccine mounted a strong antibody response against the hormone.
The patients who received the higher vaccine dose experienced significantly lower blood pressure -- with daytime systolic blood pressure (the top number of a blood pressure reading) dropping by 5.6 millimeters of mercury (mm Hg) and their diastolic blood pressure (the bottom number of a blood pressure reading, measuring pressure as the heart rests between beats) by 2.8 mm Hg.
They received injections at the start of the study, at the four-week point and then at the 12-week point. The goal is to make a vaccine to be given every four months, Nussberger said.
Other researchers who have tried to develop a hypertension vaccine did not see such positive results, he said.
The vaccine produced no serious side effects, Nussberger added, although some people experienced headaches. The aim is to develop a vaccine to be given every four months, he said.
YEARS TO GO Nussberger said he expects it will take five to 10 years before the vaccine could be ready for wide usage.
About a billion adults worldwide have elevated blood pressure.
The problem is worst in the United States and eastern Europe, affecting nearly a third of adults.
''The problem we have with hypertension patients is compliance -- lifelong, they should take pills every day,'' Nussberger told reporters. ''It reminds them every day, 'I am an old person, I am a sick person.''' ''So, if you can give him a shot, then he goes home and comes back after four months. It would be a good thing,'' Nussberger said.
Dr. Daniel Jones, president of the American Heart Association, said, ''This is not ready for application in clinical medicine yet.
But what an intriguing approach to try to have a solution to hypertension that would be easier to apply than taking medicines every day.'' The vaccine takes aim at a hormone in the body called angiotensin II that constricts blood vessels and raises blood pressure. This hormone already is an indirect target of several existing blood pressure drugs, the researchers said.
''We take non-infectious particles with a virus shape and chemically couple them with angiotensin II so the body begins to vigorously attack angiotensin II,'' Martin Bachmann, senior co-author of the study and chief scientific officer at Cytos, said in a statement.
High blood pressure, sometimes called a ''silent killer'' because it typically produces no symptoms, can lead to serious health problems including stroke, heart failure, heart attack and kidney failure.
It can be controlled by making lifestyle changes -- losing weight, exercising more, reducing salt intake, quitting smoking and others -- and taking drugs if necessary.
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