US researchers have developed a DNA vaccine that successfully held off the disease of Alzheimer in animal tests. The vaccine, if proven safe and effective in human trials, could reduce dementia cases by half.

Tests in mice have shown that the DNA vaccine reduced accumulation of both types of toxic proteins associated with the disease of Alzheimer, namely tau and beta-amyloid, without triggering severe brain swelling that earlier antibody treatments caused in some patients.The study showed that the vaccine prompted a 40 percent reduction in beta-amyloid and up to a 50 percent reduction in tau, with no adverse immune response.