Despite previously saying an emergency use authorization would not be declared by the Food and Drug Administration for convalescent plasma, the organization this week changed course and approved plasma to treat patients with COVID-19 – what President Donald Trump hailed as a “game-changer.”

The human immune system creates antibodies to fight off infection, which remain in the plasma.

Convalescent plasma is an antibody-rich product from blood donated by people who have recovered from the disease. The blood is then transfused into patients actively sick to try to help their immune systems kill the virus.

Although promising, convalescent plasma has not yet been shown to be safe and effective as a treatment for COVID-19, according to the FDA. Plasma is also difficult to scale up for treatment of millions of people. 

Dr. Carlos del Rio, distinguished professor of medicine, epidemiology and global health and executive associate dean of Emory University School of Medicine at Grady Health System, said the move appears political.

“Both Dr. Francis Collins, the director of the National Institutes of Health, and Dr. Anthony Fauci recommended against an emergency use authorization,” del Rio said. “And, in fact, initially the FDA said, ‘We're not going to do an emergency use authorization’ and then the White House convinced them to do this.”

The NIH and the Infections Disease Society of America treatment guidelines do not include plasma as standard of care, and del Rio said the data is not conclusive that this treatment makes a huge difference.

To call the therapy “a game-changer” is a long shot, he said.

While del Rio supported the White House’s emergency use authorization for remdesivir, he said, he is concerned when he hears the president or any political leader pushing for a therapy.

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“I think, unfortunately, during this epidemic, we've seen the president tout as game-changers, hydroxychloroquine and other therapies that don't have that scientific basis,” del Rio said. “And, yes, I worry when that happens, because obviously we want to be science-based.”

Mayo Clinic researchers and collaborators in June found investigational convalescent plasma to be safe following transfusion in a diverse group of 20,000 patients, but ongoing clinical trials are needed to determine the efficacy of COVID-19 convalescent plasma, he said.

Not all plasma is created equal, del Rio said. Some patients produce far more antibodies than others and, often, those willing to provide plasma were not sick enough long enough to have antibody-rich plasma.

Del Rio compared convalescent plasma to monoclonal antibodies, which are laboratory-made versions of proteins naturally produced by the immune system in response to invading viruses or other pathogens.

He said he is far more excited about monoclonal clinical trials, comparing the treatment to being like a Ferrari and convalescent plasma like a horse and buggy.

Ultimately, del Rio said he doesn't believe convalescent plasma is a breakthrough therapy.

“I'm not convinced this is the solution to our problems,” he said. “I just think this is an incremental advance in the therapy of COVID-19 that deserves further study.”