Vaccine to Prevent Recurring Strokes Shows Early Promise

An experimental vaccine could one day be used to prevent reccurring or secondary strokes, according to research published in Hypertension.

The vaccine, S100A9, currently being tested in mice, works by preventing the formation of blood clots and could be used to either replace or supplement oral blood thinners.

“Many stroke patients don’t take their blood thinning drugs as prescribed, which makes it more likely they will have another stroke. This vaccine might one day help solve this issue since it would only need to be injected periodically,” Hironori Nakagami, MD, PhD, a co-author of the study said in a statement about the vaccine.

Japanese researchers recently studied the use of the vaccine in mice and found that it provided protection against blood clots for more than two months. Importantly, the researchers also found that it didn't increase the risk of bleeding or cause an autoimmune response, meaning the mice's immune system did not see the vaccine as an "intruder," they said.

The vaccine was found to be as effective as clopidogrel in a major artery when tested in the mice.

Researchers are hopeful that one day the vaccine could either replace or be used as a complement to oral medications, giving physicians more treatment options and potentially saving more lives by preventing a secondary stroke.

Nakagami said they plan to continue to research the vaccine and would like to start clinical trials on humans in the next five to ten years.

One challenge is that differences in the immune system of mice and humans could impact how the vaccine would be recognized in the human body.

"We should be able to overcome such problems and believe this vaccine provides a very promising strategy in secondary prevention of stroke," Nakagami said.

According to the

, secondary strokes are often more deadly and are more likely to cause disability because portions of the brain have already been injured during the original stroke. It is estimated that 24% of women who've had a stroke will have a secondary stroke within five years. The rate for secondary stroke is higher for men and is estimated to occur in 42% of men within that same time frame.