Efficacy and safety of transfusing plasma from COVID-19 survivors to COVID-19 victims with severe illness. A double-blinded controlled preliminary study

Background: COVID-19 is highly contagious, potentially deadly current pandemic with no evidence-based cure or vaccines. The efficacy and safety of transfusion plasma of recovered patients were tested to treat patients with severe infection. Method: In this preliminary, controlled study, 30 patients were allocated to one of two groups: Standard therapy group (control, n = 15) and recovered COVID-19 plasma group (RCP, n = 15). Control group, received standard therapy alone, while patients allocated to RCP group, were given a single dose,250 ml, of plasma of recovered COVID-19 individuals, plus standard COVID-19 therapy. Neutralizing antibodies and severe COVID-19 serum biomarkers e.g. C-reactive protein, ferritin and d-dimer were measured in all patients before and after transfusion. Our primary outcome was reduction of two or more of a four-category illness-severity scale over 5 days study period: Respiratory frequency >= 24/min, blood oxygen saturation <= 93% on room air, partial pressure of arterial oxygen to fraction of inspired oxygen ratio < 300 mmHg, pulmonary infiltrates >50% of both lungs. Results: Plasma of recovered COVID-19 resulted in improvement of laboratory and radiological findings. In RCP group, there was statistically significant improvement of clinical parameters, as well as serum ferritin, D-dimer, c-reactive protein, and the size of lung lesion compared to control group (P <= 0.05). COVID-19 neutralizing antibodies appeared in serum of RCV patients, but failed to show in the control group patients during 5 days study period. Conclusion: Plasma of recovered COVID-19 individuals is safe and effective therapeutic modality that significantly accelerated clinical improvement in patients with severe COVID-19 infection.