Development and characterization of anti-SARS-CoV-2 intravenous immunoglobulin from COVID-19 convalescent plasma.

ABSTRACT

Background: The authors describe the developmental process of intravenous anti-COVID-19 hyperimmune immunoglobulin from anti-SARS-CoV-2 neutralizing antibody-containing plasma. Furthermore, the authors investigated its safety and protective activity in animal models. Materials & methods: The manufacturing process included standard ethanol fractionation, chromatographic purification steps and virus removal or inactivation. Results: The authors produced pure and safe immunoglobulin for intravenous administration, with 98.1 ± 6.5 mg/ml protein content, of which 97.6 ± 0.7% was IgG. The concentration factor of SARS-CoV-2 neutralizing antibodies was 9.4 ± 1.4-times. Safety studies in animals showed no signs of acute/chronic toxicity or allergenic or thrombogenic properties. Intravenous anti-COVID-19 hyperimmune immunoglobulin protected immunosuppressed hamsters against SARS-Cov-2. Conclusion: The obtained results can allow the start of clinical trials to study the safety and efficacy in healthy adults.

An intravenous immunoglobulin with a high concentration of SARS-CoV-2-neutralizing antibodies was prepared from COVID-19 convalescent plasma, which could be utilized as a passive immunization tool in regard to COVID-19 treatment. The manufacturing process employed conforms to commonly held business standards within the intravenous immunoglobulin industry and includes plasma ethanol fractionation following chromatographic purification and special virus removal or inactivation steps. The results of the preclinical in vitro and in vivo experiments demonstrate that the immunoglobulin produced in this study is pure and safe enough to be considered for intravenous applications. The SARS-CoV-2 neutralizing antibody concentration was found to have increased 9.4 ± 1.4-times compared with human plasma. The anti-COVID-19 hyperimmune immunoglobulin showed no signs of toxicity and did not cause any blood clot formations when administered to rabbits. Furthermore, the anti-COVID-19 hyperimmune immunoglobulin was demonstrated to protect immunosuppressed hamsters against SARS-CoV-2.