The Food and Drug Administration (FDA) issued an emergency use authorization yesterday for the utilization of convalescent plasma as a treatment for COVID-19. Convalescent plasma contains antibodies against the novel coronavirus that causes COVID-19. The plasma is harvested from patients who have recovered from the disease.

"The FDA determined that it is reasonable to believe that COVID-19 convalescent plasma may be effective in lessening the severity or shortening the length of COVID-19 illness in some hospitalized patients," the agency said in a press release announcing the decision.

If "reasonable" doesn't sound like a ringing endorsement, that's because it isn't. The authorization is based on two small randomized clinical trials -- neither of which reached statistical significance. The authorization also included data from nonrandomized studies and data on patients treated under an expanded access program, both of which don't have a control group, making the data hard to interpret.

This is an emergency use authorization rather than a full approval because the FDA believes "COVID-19 convalescent plasma does not yet represent a new standard of care based on the current available evidence." The agency encouraged clinical trials testing convalescent plasma to continue unaltered, to gain better evidence on whether the treatment actually helps patients.

Doctors in personal protective equipment talking to a patient

Image source: Getty Images.

Over 70,000 patients have been treated with convalescent plasma, so it seems reasonable that the agency has enough data to conclude that the treatment is relatively safe. Nevertheless, there are still some risks associated with plasma transfusion, including acute lung injury, cardiac overload, reactions to the treatment, and infections from the donors.

A consortium of biotechs and pharmaceutical companies, including CSL Behring (CSLL.Y -0.10%) and Takeda Pharmaceutical (TAK 0.15%), is working on a commercial plasma-derived antibody treatment, as is Emergent BioSolutions (EBS 2.15%).