Convalescent Plasma in COVID-19; Mortality-Safety First Results of the Prospective Multicenter FALP 001-2020 Trial

Background: The use of Convalescent Plasma (CP) to treat COVID-19 has shown promising results; however, its effectiveness remains uncertain. The purpose of this study was to determine the safety and mortality of CP among patients hospitalized with COVID-19. Study design and methods: This multicenter, open-label, uncontrolled clinical trial is currently being conducted at nine hospitals in Chile. Patients hospitalized due to COVID-19 with less than 14 days since symptom onset were eligible. Enrolled patients were classified into four groups: Patients with cancer and severe COVID-19. Patients with cancer and non-severe COVID-19. Patients with severe COVID-19 and patients with non-severe COVID-19 only. The intervention involved two 200-cc. CP transfusions with anti-SARS-CoV-2 IgG titers ≥ 1:320 collected from COVID-19-recovered donors Results: 192 patients hospitalized for COVID-19 received CP transfusions. At the first transfusion, 90.6% fulfilled the criteria for severity, and 41.1% required mechanical ventilation. 11.5% of the patients had cancer. Overall, 7-day and 30-day mortality since the first CP transfusion was 5.7% and 16.1% respectively. There were no differences at either time point in mortality between the four groups. Patients on mechanical ventilation when receiving CP had higher mortality rates than those who were not: 22.8% (95% C.I. 14.1-33.6%) vs. 11.5% (95% C.I. 6.3–18.9%) (p=0.037). Overall, 30-day mortality was higher in patients over 65 than in younger patients: 26.7% (95% C.I. 16.1– 39.7%) (p=0.019). Severe adverse events were reported in four patients (2.1%) with an overall transfusion-related lung injury rate of 1.56%. No CP-related deaths occurred. Discussion: CP is safe when used in patients with COVID-19 even when also presenting severity criteria or risk factors. Our mortality rate is comparable to reports from larger studies. Controlled clinical trials are required to determine efficacy. Conclusion: CP is safe when used in the COVID-19 population even for those who present severity criteria and/or risk factors for poor prognosis including cancer. In-depth analyses of the serological and molecular characteristics of CP are needed to evaluate the efficacy of this intervention through controlled clinical trials. Registration: NCT04384588