Matched Cohort Study of Convalescent COVID-19 Plasma Treatment in Severely or Life Threateningly Ill COVID-19 Patients

Background: The utility of convalescent coronavirus disease 2019 (COVID-19) plasma (CCP) in the current pandemic is not well defined. We sought to evaluate the safety and efficacy of CCP in severely or life threateningly ill COVID-19 patients when matched with a contemporaneous cohort.

Methods: Patients with severe or life-threatening COVID-19 were treated with CCP according to Food and Drug Administration criteria, prioritization by an interdisciplinary team, and based on CCP availability. Individual-level matched controls (1:1) were identified from patients admitted during the prior month when no CCP was available. The safety outcome was freedom from adverse transfusion reaction, and the efficacy outcome was a composite of death or worsening O₂ support. Demographic, clinical, and laboratory data were analyzed by univariate and multivariable regression analyses accounting for matched design.

Results: Study patients (n = 94, 47 matched pairs) were 62% male with a mean age of 58, and 98% (90/94) were minorities (53% Hispanic, 45% Black, non-Hispanic) in our inner-city population. Seven-day composite and mortality outcomes suggested a nonsignificant benefit in CCP-treated patients (adjusted hazard ratio [aHR], 0.70; 95% CI, 0.23-2.12; P = .52; aHR, 0.23; 95% CI, 0.04-1.51; P = .13, respectively). Stratification by pretransfusion mechanical ventilation status showed no differences between groups. No serious transfusion reactions occurred.

Conclusions: In this short-term matched cohort study, transfusion with CCP was safe and showed a nonsignificant association with study outcomes. Randomized and larger trials to identify appropriate timing and dosing of CCP in COVID-19 are warranted.

Trial registration: ClinicalTrials.gov Identifier: NCT04420988.