In a U.K. study involving 11,558 hospitalized COVID-19 patients, the use of convalescent plasma did not improve survival rates or other clinical outcomes, according to findings published May 14 in The Lancet.
The findings, part of the U.K.'s Randomized Evaluation of COVID-19 Therapy trial, known as RECOVERY, compared the outcomes of 5,795 hospitalized patients who received convalescent plasma to those of 5,763 hospitalized patients who did not get the treatment and received usual care.
The 28-day mortality rate was 24 percent in each group, the findings showed. The share of patients released from the hospital within 28 days was also the same across both groups at 66 percent. Additionally, researchers did not find convalescent plasma to reduce the need of requiring mechanical ventilation.
"Convalescent plasma has been widely used for COVID-19 outside of clinical trials, but, until now, there has been insufficient evidence from randomized trials to reliably assess its safety and efficacy," researchers said. "In RECOVERY, the largest clinical trial of convalescent plasma for any infectious indication, we did not find evidence that high-titre convalescent plasma improved survival or other prespecified clinical outcomes in patients hospitalized with COVID-19. Whether convalescent plasma would benefit other patient groups is unknown and would need to be evaluated in other, adequately powered, randomized clinical trials."
In the U.S., hospitals have largely abandoned the use of convalescent plasma, citing a growing body of underwhelming evidence about the treatment's effectiveness.