Convalescent Plasma Immunotherapy - A Possible Mitigation Strategy for SARS-CoV-2 Pandemic

Abstract

Recently, a newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused a pandemic coronavirus disease (COVID-19). More than 10 million confirmed cases and 503,867 associated deaths of SARS-CoV-2 have been reported worldwide to WHO in the end of July 2020. According to WHO guidelines, there is no effective therapy available for treating devastating SARS-CoV-2. Consequently, lack of evidence for appropriate treatment and vaccines has led to the re-emergence of convalescent plasma (CP) immunotherapy. Herein, we discuss the historical perspectives of CP against SARS-CoV, MERS-CoV, H1N1 pandemic and mainly the clinical outcomes of COVID-19 patients with respect to neutralizing antibodies (nAbs). A brief possible clinical protocol for CP transfusion with its adverse effects and limitation were also highlighted. It is concluded that, CP transfusion with high neutralizing antibody titer administered in early course of disease significantly improved clinical outcomes in COVID-19 patients by reducing morbidity and mortality. Thus, CP immunotherapy is considered as noteworthy candidate to be further re-evaluated as a most suitable therapeutic option against SARS-CoV-2 pandemic.