ORLANDO, Fla. Researchers presenting Tuesday at the American Heart Association annual meeting in Orlando, Fla., said that a vaccine could forestall the need to take drugs every day.
“It was a small dose, and the trial was done in a conservative way, but there was not only safety and tolerability—we also had efficacy with blood pressure,” said study author Dr. Juerg Nussberger, a professor of medicine at University Hospital of the Canton of Vaud in Lausanne, Switzerland. Nussberger also has an interest in Cytos Biotechnology, which produces the vaccine.
American Heart Association president Dr. Daniel Jones said that there are great benefits to the vaccine, including lack of compliance issues and much more.
Almost one in three Americans suffers from high blood pressure, which increases the risk of stroke, heart disease, heart failure and kidney failure. Part of the problem, researchers said, may be the nuisance for patients following complex medication regimens. Simplicity, researchers noted, produced more benefits.
“The problem is that lifelong, they have to take a pill a day,” Nussberger said. “If you can give them a shot, they go home and … later they come back. It would be a good thing.”
This new vaccine, known as CYT006-AngQb, works by reducing angiotensin II, a molecule that constricts blood vessels and raises blood pressure. Several existing medications target the same molecule, including ACE (angiotensin-converting enzyme) inhibitors and ARBs (angiotensin receptor blockers).
For this trial, 72 volunteers with mild to moderate high blood pressure were injected with 100 or 300 micrograms (ug) of the vaccine or a placebo at zero, four and 12 weeks from the start of the trial. Volunteers included 65 men and seven women, average age 51.5 years.
After 14 weeks, systolic blood pressure (the top number in a reading) in the high-dose group was reduced by 5.6 mm Hg and diastolic blood pressure (the bottom number) fell by 2.8 mm Hg.
Additionally, the vaccine seemed to diminish the typical blood pressure surge that occurs between 5 a.m. and 8 a.m., which is the time frame when the body is most at risk to a heart attack, stroke, heart and kidney failures, the research pointed out.
Meanwhile, the vaccine also produced a slight increase in renin levels. Renin is an enzyme that is thought to cause inflammation and may play a role in kidney failure.
The vaccine needs further testing, presenters of the data said, to determine if the body has the ability to raise blood pressure if and when needed.