Convalescent Plasma to Treat Covid-19: a Randomized Double Blind 2 Centers Trial

Abstract In SARS-CoV-2, there is an overactivation of the immune system that triggers systemic hyperinflammation that causes lung damage; therefore, the use of convalescent plasma (CP) has been considered for its immunological mechanisms that could benefit patients in moderate and severe stages of the disease. This study evaluated the safety and efficacy of the use of convalescent donor plasma for COVID-19 to reduce mortality in patients with SARS-CoV-2 stage II (moderate) and stage III (severe) disease.Material and methodsA double-blind, randomized controlled clinical trial was conducted from May 20 to December 10, 2020. Thirty-nine participants with moderate (II) and severe (III) stage COVID-19 confirmed by RT-PCR and tomography were included. The study randomization rate was set at 3:1. Convalescent plasmas were chosen for application with a neutralizing antibody titer of ≥ 1:32. Patient follow-up included assessment by Sequential Organ Failure Assessment (SOFA) score and use of the Oxygenation Index (PAO2/FIO2) index and monitoring of blood markers, such as C Reactive Protein (CRP), D-Dimer (DD), ferritin, IgG antibody titers against SARS-COV-2, and inflammatory cytokines at days three and seven post-treatment.ResultsWe observed a significantly lower 21-day post-transfusion mortality HR: 0.17 [95.0% CI 0.07-0.45, p<0.001] in the group receiving convalescent plasma compared to the control group; protective units (PU) in the group receiving convalescent plasma after seven days were significantly higher 512 (32-16384) vs 96 (32-256), p=0.01; the SOFA scale decreased to 3.7 ± 2.02 vs 7.1 ± 2.8, p<0.001 and the PAO2/FIO2 index showed a significant improvement in the group receiving convalescent plasma 251.01 ± 109.4 vs 109.2 ± 62.4, p<0.001, vs the control group. In terms of safety, no adverse events related to the transfusion of convalescent plasma were observed.ConclusionConvalescent plasma is safe and effective, as it decreases mortality in the convalescent plasma group compared to the control group.