Convalescent Plasma Early on Helps Prevent Severe COVID-19, Study Finds

A small randomized trial in Argentina has found that the early use of convalescent plasma in COVID-19-infected adults helped to reduce progression to severe disease.

The study in 160 patients age 65 years and older treated with either convalescent plasma or a placebo found that only 13 of 80 participants (16 percent) given the treatment developed severe respiratory disease. The patients were given convalescent plasma or placebo within 72 hours of showing mild COVID-19 symptoms.

By comparison, 25 of 80 patients (31 percent) give a placebo developed severe respiratory disease, according to findings published in the New England Journal of Medicine. The researchers found that treatment with convalescent plasma provided a relative risk reduction of 48 percent and caused no adverse events.

“Early administration of high-titer convalescent plasma against SARS-CoV-2 to mildly ill infected older adults reduced the progression of COVID-19,” the researchers concluded, though they noted they had to stop the trial at 76 percent enrollment due to declining numbers of coronavirus cases in Buenos Aires.

The researchers said that their trial was different than previous trials of convalescent plasma because it focused on older patients and they administered the treatment within three days of diagnosis compared to the eight to 30-day range seen in other studies.

“Our findings underscore the need to return to the classic approach of treating acute viral infections early,” they said.

The findings are significant because convalescent plasma is currently cleared by the FDA under Emergency Use Authorization (EUA) for treating hospitalized patients. The agency’s authorization was controversial, with experts balking at the lack of data supporting a benefit for treating severe COVID-19 and some suggesting the EUA was in response to political pressure. The outcry intensified when FDA Commissioner Stephen Hahn publicly misrepresented the treatment’s efficacy (DID, Aug. 26, 2020). The commissioner later apologized.

Mixed results have been seen for convalescent plasma as a treatment for severe COVID-19 and experts have called for larger, randomized trials to evaluate the treatment’s safety and efficacy. National Institutes of Health guidelines neither recommend nor discourage it as a coronavirus treatment, citing insufficient data.

Read the trial results here: bit.ly/3hSGGT5. — James Miessler