Angiotensin II is a blood chemical that causes vasoconstriction and increased blood pressure.
In the 14-week trial, 72 patients were randomly selected to either receive a placebo, or injected with either 100ug or 300ug doses of the vaccine in weeks 0, four and 12.
In the 300 ug group, there was a reduction in of 9.0 and 4.0 mm/Hg for mean ambulatory systolic and diastolic blood pressure compared with placebo.
It also reduced the early morning blood pressure surge by 13mm/Hg compared with placebo.
Lancet (2008) 371: 821-827