Use of plasma therapy shouldn't be considered as standard of care for Covid-19, NIH disputes Trump endorsement
At a press conference on August 23, US President Donald Trump hailed the treatment, calling it safe and effective
There isn't enough evidence to support the use of plasma therapy for treating hospitalized Covid-19 patients, a panel of experts from the National Institute of Health said. The statement comes days after the US Food and Drug Administration (FDA) announced an emergency approval of the treatment, despite a lack of data on its safety and efficacy.
"There are insufficient data to recommend either for or against the use of convalescent plasma for the treatment of Covid-19," the NIH panel said in a statement. This was because there was no data from experiments that are considered gold-standard for evaluating a treatment: well-controlled, adequately powered randomized clinical trials. Plasma is a yellow liquid portion of the blood that is rich in antibodies. The idea behind the treatment [convalescent plasma] is collecting plasma from survivors of the disease and administering it to the infected patients. It is a century-old practice that was used against the flu and measles in the past.
At a press conference on August 23, US President Donald Trump hailed the treatment, calling it safe and effective. FDA Commissioner Stephen Hahn told reporters that convalescent plasma could cut Covid-19 deaths by 35%. That claim, however, was found to be inaccurate.
Writing an open letter to Hahn, Eric Topol, the editor-in-chief of Medscape and a professor of molecular medicine at The Scripps Research Institute said: "We cannot entrust the health of 330 million Americans to a person who is subservient to President Trump’s whims, unprecedented promotion of unproven therapies, outrageous lies, and political motivations". He added: “You have two choices to do the right thing. We cannot and will not rest until you make that choice. Following the backlash, the FDA Commissioner has walked back on his claim.
I have been criticized for remarks I made Sunday night about the benefits of convalescent plasma. The criticism is entirely justified. What I should have said better is that the data show a relative risk reduction not an absolute risk reduction.— Dr. Stephen M. Hahn (@SteveFDA) August 25, 2020
Hahn's claim comes from an unpublished study, which compared patients who received plasma with a high concentration of antibodies with those who were given a lower amount. The authors found “no difference in 7-day survival overall”. But the findings showed some benefits for people hooked to a ventilator: 11% of participants who received the treatment with high antibody levels died within 7 days, compared with 14% who were given lower levels.
Although the data suggest that plasma with high antibody may benefit patients who are not connected to a ventilator for breathing support, there is still uncertainty about the efficacy and safety of the treatment, the experts said of the unpublished study.
The current data suggest that adverse reactions to the plasma therapy were "infrequent". But, they add, the data on long-term risks and whether it could weaken a patient's immune response to a second infection is not clear. "Convalescent plasma should not be considered standard of care for the treatment of patients with Covid-19," they noted.
"Prospective, well-controlled, adequately powered randomized trials are needed to determine whether convalescent plasma is effective and safe for the treatment of Covid-19," they wrote. "Members of the public and health care providers are encouraged to participate in these prospective clinical trials."