Is there a vaccine for Alzheimer's disease?

No. There is no vaccine for Alzheimer's. It is a disease that older people develop that affects the way their brain functions. It is not an infection and therefore cannot be prevented with vaccination.
One day it may be possible to prevent or treat Alzheimer's disease with a vaccine. Several such vaccines are under development.

The very notion of an Alzheimer's vaccine is a bit unconventional. Most vaccines stimulate the immune system to produce antibodies against a virus. Then researchers found that injecting beta-amyloid protein into mice stimulated the immune system to produce antibodies against beta-amyloid. These antibodies accomplished a remarkable feat: they cleared beta-amyloid plaques, one of the main physical signs of Alzheimer's disease, from the brain.

In 2001, a vaccine called AN-1792 was tested on 300 people with Alzheimer's disease to see if it was safe and effective in improving symptoms. Another 75 people took a placebo. The trial was discontinued when 15 people given the vaccine developed a nonfatal brain inflammation. Fortunately, with treatment, all improved or recovered. Researchers continued to follow other study participants, and they found that 20% of those who were vaccinated had an immune response, and that all of those who did also experienced marked improvements in activities of daily living, a sign that the vaccine slowed the progression of the disease. The greatest improvements were in the people with the greatest antibody response to the vaccine.

In addition, autopsies of the vaccinated participants who later died of Alzheimer's-related complications showed that large areas of their brains were clear of amyloid plaques, an indication that the vaccine may have reversed some of the brain damage caused by the disease.

Researchers are trying to develop a safer Alzheimer's disease vaccine. One approach is "passive vaccination," the use of antibodies to beta-amyloid to clear the brain of amyloid plaque, as opposed to "active" vaccination with beta-amyloid itself. In experiments with mice, passive vaccination has had the same plaque-clearing effects as active vaccination. Large, multicenter trials to test passive vaccination and a new version of active immunization are in progress.

Another passive immunization agent, intravenous immunoglobulin, was in phase III trials for Alzheimer's at the time this report was printed. Because this substance is already Food and Drug Administration (FDA)-approved to treat people with immune deficiencies, its safety profile is well known; whether it will be effective for Alzheimer's patients remains to be seen.

Continue Learning about Alzheimer's Disease Prevention

Alzheimer's Disease Prevention

Alzheimer's Disease Prevention

In simple terms, Alzheimer's disease is a progressive, but preventable, brain disease that causes a decline in memory and thinking skills over time. To prevent Alzheimer's disease, keep your brain and body active through exercise, ...

eat a healthy diet and load up on memory-saving vitamins E and B. Find out more ways to prevent Alzheimer's disease from our Sharecare experts

Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.