For the majority of people with high blood pressure the long-term solution is daily pills and frequent monitoring from your physician with alterations to your dose or changes in your tablets as necessary. So how much better would life be if you could simply be vaccinated against high blood pressure and forget about the nuisance of your daily tablets?
Almost one in three Americans are suffering from high blood pressure but, because of the complex mix of tablets frequently necessary for treatment, only some one third of these people in fact have their blood pressure under control. But, this could be set to change in the future.
In a trial which was carried out earlier this year (2007) 72 patients (7 women and 65 men with an average age of 51 years 6 months) who were suffering from mild or moderate hypertension were given a low dose (100 micrograms) vaccine, a high dose (300 micrograms) vaccine or a placebo. This injection was repeated after a month and at the end of three months.
Fourteen days after the last injection it was found that the high dose vaccine patients were showing a fall of more than 5 mm Hg in their systolic blood pressure and almost 3 mm Hg in their lower diastolic blood pressure.
Possible more notable, it was also discovered that the characteristic, and potentially dangerous, spike in blood pressure which happens in the morning between 5 am and 8 am was also down considerably by 25 mm Hg systolic and 13 mm Hg diastolic.
The trial patients all tolerated the vaccine without problem and there were no safety issues during the trial.
So exactly how does the vaccine work?
At the moment blood pressure is controlled using a variety of drugs which are designed to act in different ways. Two of the classes of drugs often used are angiotensin-converting enzyme (ACE) inhibitors (such as Lotensin, Vasotec, Capoten, Monopril, Altace, Aceon, Univasc and Zestril) and angiotensin-2 (AT-2) receptor blockers (such as Atacand, Avapro, Micardis, Cozaar and Teveten). In both cases these drugs block the action of a molecule which causes the blood vessels to constrict and consequently to raise the pressure within the blood vessels.
The vaccine used in the trial, which is called CYT006-ANgQb, is designed to work in the same way as these two currently used drugs and so should certainly be an alternative for those individuals whose blood pressure is presently controlled using AT-2 receptor blockers or ACE inhibitors.
But what about those individuals whose blood pressure is being controlled using the alternatives of beta blockers (such as Sectral, Corgard, Ziac, Toprol XL, Blocadren, Cartol, Tenormin, Betapace, Lopressor and Zebeta) or calcium channel blockers (such as Norvasc, Adalat, Nimotop, Cardizem, Procardia, Plendil, Sular, Isoptin, Calan and Verelan)?
Well, it is very early days yet and additional trials will be required before we see a vaccine in everyday use for the control of high blood pressure. However, if the scientists are correct, it seems likely that this vaccine will be effective for a lot of sufferers, whatever the treatment presently being given.
Naturally time will tell, but this is obviously an extremely encouraging development.
