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Study renews hope in using convalescent plasma to treat COVID-19

One key is timing: Patients need to get it before they’re hospitalized, according to the study, which has not been peer-reviewed

Hasbro Children’s Hospital, one of the top sites for the study.Pat Greenhouse/Globe Staff

PROVIDENCE — The treatment is made in human bodies, instead of a lab: the blood plasma from people who have recovered from COVID-19.

So-called convalescent plasma has also proved medically uncertain, with a scientific consensus that seems to shift as often as the dietary benefits of eggs: After initial promise, multiple studies showed that when people were hospitalized with COVID-19, they were not significantly less likely to die after being given the blood plasma of donors who had recovered from the virus.

But a new study from researchers around the country, including in Rhode Island, is bringing renewed hope for the use of convalescent plasma. One key is timing: Patients need to get it before they’re hospitalized. The study showed a 54 percent reduction in the risk of hospitalization among people who received convalescent plasma versus those who received a placebo.


“This is an important treatment that can keep you out of the hospital,” said Dr. Adam Levine, an emergency medicine physician at Lifespan who led the study in Rhode Island. “It’s important as an individual. It’s also important in terms of reducing hospitalizations to avoid overwhelming the health care system.”

Rhode Island was one of the top centers for the Johns Hopkins University-based study, which enrolled 1,181 patients around the country. The study is available on the site MedRxiv as a pre-print, meaning it hasn’t been peer reviewed.

In Rhode Island, adults who started having COVID-19 symptoms within eight days came into one of two rooms in the emergency department of Hasbro Children’s Hospital to get the infusion treatment. (The children’s hospital was markedly less busy throughout the pandemic because children are much less susceptible than older people to COVID-19, and because limits on social activities and sports kept kids from getting hurt.)

The study showed that getting the treatment to people before they were hospitalized can help, even as other studies have showed it won’t make a difference by the time patients need to be in the hospital. That makes medical sense, Levine said: By the time patients are in the hospital, the virus itself had already done its damage, and the cascade of inflammation had begun. Antibodies from donors’ blood would no longer be of much use. Instead patients need something to deal with the inflammation and related complications.


But getting it to people early would give their bodies a chance to fight off the virus, heading it off before it can do its most significant damage.

Another key, Levine said: They used “high titer” plasma, or plasma that’s rich with antibodies. Some people who recover from COVID have high titer plasma, and some do not. Levine said early indications show that people who are vaccinated, but have breakthrough infections, have blood with very high antibody levels.

The study is particularly important in the context of Omicron and other variants of the virus that causes COVID-19, Levine said. Omicron in particular has proven resistant to some of the lab-made monoclonal antibodies. But when someone gets sick with Omicron, their body makes antibodies specifically against Omicron. That could help people who get the same variant, or new ones as they arise. Our bodies, in other words, are retooling to help fight off the virus more quickly than researchers in a lab can.

That’s potentially good news not just in the U.S., but in areas of the world with less access to scarce resources.


Levine noted that the U.S. Food and Drug Administration last Tuesday updated its authorization for the use of convalescent plasma to include use in outpatient settings, in addition to inpatient settings. The authorization is for use in people who are immunosuppressed. That can include broad swaths of people vulnerable to the disease, like those with heart conditions, diabetes or the elderly.

Levine said policymakers in Rhode Island could use convalescent plasma in the very same settings that it’s now using the lab-made monoclonal antibodies. They require the same set-up: a transfusion site and somewhere to sit for an hour for observation.

Levine said the medical community also needs to redouble its efforts to get people who have recovered from COVID-19 to donate their plasma, an effort that fell off when it proved ineffective in people who were already hospitalized.

“Now we have to ramp that up again,” Levine said.

Brian Amaral can be reached at brian.amaral@globe.com. Follow him on Twitter @bamaral44.