Convalescent Plasma Falls Flat in New Study

November 25, 2020
Killian Meara

Important finding shows convalescent plasma provides no significant benefit in severe COVID-19 cases.

Convalescent plasma transfusions have long been touted as a potential treatment for patients with coronavirus disease 2019 (COVID-19) induced severe pneumonia. The treatment has been frequently administered to patients with COVID-19 based largely on observational data. However, there is a minimal amount of data from controlled, randomized studies to support the use of this therapy.

A new study, published in The New England Journal of Medicine, found that there was no observed significant difference in the clinical status or overall mortality in patients administered a convalescent plasma transfusion when compared to a placebo. This research supports other recently published studies that have come to a similar conclusion.

News of the research has been making the rounds on social media. On Twitter, Contagion® Editor-in-Chief Jason Gallagher, PharmD, tweeted, “swing and a miss in an RCT for convalescent plasma for severe Covid19. >90% received steroids Median days of symptoms were 8; 46% of those tested had no detectable antibodies at baseline. In the supplement, no trend towards efficacy for those ppl.”

The study was a double-blind- placebo-controlled, multicenter trial in 12 clinical sites throughout Argentina. The researchers were supported by the Hospital Italiano de Buenos Aires. Trial participants were assigned in a random 2:1 ratio, either receiving a placebo or the convalescent plasma transfusion in addition to standard treatment. The plasma was collected from donors with a total SARS-CoV-2 total antibody titer of 1:400.

The primary outcome of the study showed no significant difference between the plasma group and the placebo group after 30 days of treatment. Secondary outcomes included no significant difference in mortality rate or clinical status between the 2 groups. No noted differences were demonstrated in time to death or in the time to clinical improvement.

The discoveries from the study go against numerous findings from a series of nonrandomized studies that touted the power of convalescent plasma transfusion in treating patients with COVID-19. This apparent contrast demonstrates the importance of randomized, controlled trails, especially during a pandemic.

“In our trial, the use of convalescent plasma therapy in addition to standard treatment in patients with severe pneumonia due to Covid-19 did not reduce mortality or improve other clinical outcomes at day 30 as compared with placebo,” lead author Ventura A. Simonovich, MD, wrote. “We believe the use of convalescent plasma as a standard of care in such patients should be reevaluated.”