Collecting and evaluating convalescent plasma for COVID‐19 treatment: why and how?

Abstract

Plasma provided by COVID-19 convalescent patients may provide therapeutic relief as the number of COVID-19 cases escalates steeply worldwide. Prior findings in various viral respiratory diseases including SARS-CoV-related pneumonia suggest that convalescent plasma can reduce mortality, although formal proof of efficacy is still lacking. By reducing viral spread early on, such an approach may possibly downplay subsequent immunopathology. Identifying, collecting, qualifying and preparing plasma from convalescent patients with adequate SARS-CoV-2-neutralizing Ab titres in an acute crisis setting may be challenging, although well within the remit of most blood establishments. Careful clinical evaluation should allow to quickly establish whether such passive immunotherapy, administered at early phases of the disease in patients at high risk of deleterious evolution, may reduce the frequency of patient deterioration, and thereby COVID-19 mortality.

The role of passive immunization in the age of SARS-CoV-2: an update

“…Meanwhile there a several publications, which show that the renaissance of passive immunization could be a bridging technology until effective medications or an active immunization is available. [2][3][4][5][6][7][8][9][10].…”

Passive Immunity for Coronavirus Disease 2019: A Commentary on Therapeutic Aspects Including Convalescent Plasma

“…No serious adverse events have been reported with convalescent plasma transfusions in a 2015 systematic review or in a trial for Ebola disease. 64 Minor adverse events, mostly temperature increase and/or itching or skin rash, were observed in 8% of patients. There are two case reports of possible transfusion-related acute lung injury (TRALI) reported on convalescent plasma in a patient with Ebola disease and in another patient with MERS-CoV; however, the plasmas did not contain anti-HLA or antihuman neutrophil antibodies.…”

“…The role of convalescent plasma and how to use it for treating COVID-19 was recently reviewed. 64 Neutralizing antibody responses peaked at 4 months and then decreased to undetectable levels in 16 to 48% of patients at 36 months. A significant portion of patients who had detectable antibodies at 36 months had persistent viral neutralizing activity.…”

“…Based on previous studies, the transfusion should occur early in the course of the severe COVID-19 infection, ideally within 5 days. 58,64 It is recommended to begin with one unit of plasma ( 200-250 mL) infused at a slow rate with close monitoring for adverse transfusion reactions including allergic and febrile reactions, circulatory overload, and possible evidence of systemic or pulmonary inflammatory reactions. If available, repeat convalescent plasma transfusions can be considered in the next 24 to 48 hours, depending on how the patient tolerated the first transfusion and on the clinical response.…”

Immunoglobulin fragment F(ab’)2 against RBD potently neutralizes SARS-CoV-2 in vitro

“…Polyclonal antibodies such as convalescent plasma from recovered patients were usually made as emergency treatments for emerging infectious diseases [10][11][12][13] . However, lack of blood source and risk of blood-borne diseases impede the wide clinical application of convalescent plasma 14 . Antisera produced by large animals like horses through passive immunization provides an alternative for that [15][16][17] .…”