Convalescent Plasma in Critically ill Patients with COVID-19

BACKGROUND The evidence for benefit of convalescent plasma for critically ill patients with Covid–19 is inconsistent. We hypothesized that convalescent plasma would improve outcomes for critically ill adult patients with Covid–19. METHODS In an ongoing adaptive platform trial, critically ill patients with confirmed Covid–19, defined as receiving intensive care–level organ support, were randomized to open–label convalescent plasma or not (i.e., control group). The primary end point was organ support–free days (i.e., days alive and free of ICU–based organ support) up to day 21. The primary analysis was a Bayesian cumulative logistic model with predefined criteria for superiority or futility. An odds ratio greater than 1 represented improved survival, more organ support–free days, or both. RESULTS The convalescent plasma intervention was stopped after pre–specified criteria for futility were met. At that time, 1084 participants had been randomized to convalescent plasma and 916 to no convalescent plasma (control). The median organ support-free days were 0 (interquartile range, −1 to 16) for the convalescent plasma group and 3 (interquartile range, −1 to 16) days for the control group. The median adjusted odds ratio (OR) was 0.97 (95% credible interval 0.83 to 1.15) and posterior probability of futility (OR < 1.2) was 99.4% for convalescent plasma compared to control. In-hospital mortality was 37.3% (401/1075) in convalescent plasma group, and 38.4% (347/904) in controls. The observed treatment effects were consistent across primary and secondary outcomes. CONCLUSIONS In critically ill adults with confirmed Covid-19, treatment with convalescent plasma, did not improve clinical outcomes. Clinicaltrials.gov: NCT02735707