ST. LOUIS — Researchers at Washington University could be on the verge of a breakthrough treatment for people suffering from COVID-19.

Tuesday, the FDA signed off on the emergency use of something known as "convalescent plasma." It's the process of taking blood from survivors of a disease and using the antibodies they develop to treat critically ill patients. 

"This is a stone-age approach for the modern age," said Dr. Jeffery Henderson, a physician and researcher with the Washington University School of Medicine. 

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Henderson, along with researchers at Johns Hopkins University and the Mayo Clinic, requested permission from the FDA to use "convalescent plasma" to treat COVID-19 patients. 

"The immune system of somebody who's already seen the disease can be used to give an assist to somebody who hasn't yet seen the disease," Henderson said.

This is not a cure for the virus, he added. Instead, the process could prevent the disease "for a short period of time," Henderson said. "Another possibility is that it is a treatment or makes the disease less severe."

Which is how it is likely to be used first -- as a way to help the most critically ill beat the disease. While Henderson and his team are testing this technique on COVID-19, the FDA approval allows them to use it immediately on the critically ill.

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"In medicine ... to use some St. Louis metaphors ... we're always going for a home run," Henderson said. "But I think it's important we don't forget about getting base hits every so often as well. And I think this is perhaps an example of that."

Even though this process has been approved to help critically ill patients right away, Henderson says it will likely take a few weeks to get qualified donors and get their plasma to the people who need it. 

The doctor stresses that when they start trying this treatment only recovered patients with a documented positive test and two weeks symptom-free will be eligible to donate their plasma to help other people.

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