On Apr. 2, 2020, Cerus announced that the International Society of Blood Transfusion (ISBT) Working Party on Global Blood Safety issued a new document titled ‘Points to consider in the preparation and transfusion of COVID-19 convalescent plasma.’

The document indicates that following the donation of the convalescent plasma, the use of a licensed pathogen inactivation technology is ﾓhighly desirable to reduce the risk of transfusion transmitted infections and alleviate concerns about ‘possible superinfections with SARS-CoV-2’.

Passive immunity has been demonstrated effective for treatment of infections caused by cytomegalovirus (CMV), hepatitis B virus, rabies, tetanus, varicella, prior SARS viruses, Argentine Hemorrhagic Fever, and various other illnesses. Convalescent plasma has been cited as a potential therapy for viral infection dating back to the 1918 Spanish influenza A (H1N1) pandemic. Since that time, convalescent plasma as passive immune therapy has been evaluated in the treatment of: Ebola, SARS coronavirus (SARS-CoV), 2009 pandemic influenza A (H1N1), Argentine Hemorrhagic Fever, CMV, Parvovirus B19, and others.

Two preliminary clinical series from China reported that transfusion of COVID-19 convalescent plasma resulted in improved clinical status for patients requiring mechanical ventilation (Shen, Wang et al. 2020) and significant improvement in clinical symptoms, blood oxygen saturation, and clearance of SARS-CoV-2 virus (Duan, Liu et al. 2020).

The transfusions were well tolerated in both studies. Use of convalescent plasma is supported by a February 2020 WHO report which states “The cellular infectivity of the isolated viruses could be completely neutralized by the sera collected from convalescent patients.”