A Post-Stroke Vaccine That Could Save Lives

By Jane Farrell

A vaccine may someday replace oral blood thinners to reduce the risk of secondary strokes, researchers say.

The discovery was published in the American Heart Association’s journal Hypertension.

People who have had a stroke caused by a blood clot (ischemic strokes) often need to take oral medications that make their blood less likely to clot, which helps prevent another stroke.

The vaccine worked as well as the oral blood thinner clopidogrel.

Japanese researchers successfully tested an experimental vaccine in mice and found that it provided protection against blood clots for more than two months without increasing the risk of bleeding or causing an autoimmune response. The lack of an autoimmune response is important, because it means the animal’s immune system did not perceive the vaccine as an “intruder” that needed to be attacked.

The vaccine, S100A9, also worked as well as the oral blood thinner clopidogrel in a major artery, according to Hironori Nakagami, M.D., Ph.D., study co-author and professor at Osaka University, in Japan.

Developing a vaccine to replace and/or complement dailyoral medications might save many lives and help prevent both secondary strokes and possibly heart attacks, according to Nakagami. “Many stroke patients don’t take their blood thinning drugs as prescribed, which makes it more likely they will have another stroke,” he said. “This vaccine might one day help solve this issue since it would only need to be injected periodically.