With a vaccine for covid-19 still a long way from being realized, Johns Hopkins immunologist Arturo Casadevall is working to revive a century-old blood-derived treatment for use in the United States in hopes of slowing the spread of the disease. 

The technique uses antibodies from the blood plasma or serum of people who have recovered from COVID-19 infection to boost the immunity of newly infected patients and those at risk of contracting the disease. These antibodies contained in the blood’s serum have the ability to bind to and neutralize SARS-CoV-2, the virus that causes COVID-19.  

“Deployment of this option requires no research or development. It could be deployed within a couple of weeks since it relies on standard blood-banking practices,” says Casadevall, who published a paper on the proposal — “maybe the most important paper of my life,” he says — on March 13 in The Journal of Clinical Investigation. 

On March 24, the U.S. Food and Drug Administration (FDA) began allowing researchers to request emergency authorization for its use. Within three days, hospitals in Houston and New York City started treatments, and now under an FDA “expanded access program,” soon “a very large number” of U.S. hospitals will follow suit, says pathologist Aaron Tobian, director of the Division of Transfusion Medicine at The Johns Hopkins Hospital. 

At Johns Hopkins, the FDA has paved the way for researchers to proceed with clinical trials to test convalescent plasma therapy in people who are at high risk of severe COVID-19 illness and have been exposed to people who have tested positive for the virus.  

“We’ve received many inquiries from health care providers looking to ramp up their ability to deliver this therapy,” says Johns Hopkins pathologist Evan Bloch. In response, on April 7, Bloch and colleagues published a clinical guidebook in The Journal of Clinical Investigation to help hospitals rapidly scale up their ability to deliver convalescent plasma therapy. 

“This paper details the nuts and bolts of how to deploy convalescent plasma, and this information should be very helpful to colleagues worldwide who are preparing to use this therapy against COVID-19,” says Casadevall. 

The guidebook also outlines a range of clinical trials underway or planned at hospitals taking part in the Johns Hopkins-led network for convalescent plasma therapy.