The U.S. Food and Drug Administration (FDA) is revising its emergency use authorization of convalescent blood plasma for the treatment of patients with COVID-19, originally issued in August 2020.
The agency will limit the use of plasma to treat hospitalized patients with a medical condition impairing their ability to make antibodies or who are early in the course of the disease. Only plasma containing high concentrations of antibodies will be authorized for use.
“The update is meant so convalescent plasma can best be used on those who will benefit,” Peter Marks, MD, PhD, director of the FDA’s Center for Biologics Evaluation and Research, said. “It is being used somewhat more indiscriminately.”
The FDA reached its decision to scale back the authorization after evaluating contradictory results from several clinical trials. Two studies shut down in January after researchers found no benefit. Three other clinical trials recently reported some benefit, but only when patients received plasma soon after hospital admission. Another showed that elderly non-hospitalized patients who received plasma shortly after first showing symptoms were less likely to develop severe disease.
Currently, a large National Institutes of Health study is evaluating convalescent plasma in patients with COVID-19 who are sick enough to come to the emergency room but have yet to be admitted to the hospital, and other trials are testing the treatment’s efficacy in outpatients.
“Physicians in the U.S. for the first time are going to have guidance on when to use [convalescent plasma] and how to use [it],” said Arturo Casadevall, MD, PhD, chair of molecular microbiology and immunology at the Johns Hopkins Bloomberg School of Public Health, calling the authorization’s revision a step forward.