Development and Characterization of Hyperimmune Anti-SARS-CoV-2 Intravenous Immunoglobulin From COVID-19 Convalescent Plasma

Abstract

Background: Polyclonal immunoglobulin G (IgG) medications have successfully treated different bacterial and viral infections for several decades. Herein, we describe the development process of hyperimmune anti-Coronavirus disease 2019 (COVID-19) intravenous immunoglobulin (COVID-globulin) from anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibody (nAb)-containing plasma. Furthermore, we investigate the safety and protective activity of the COVID-globulin in animal models.Methods: COVID-19 convalescent plasma samples collected from Russian blood service organizations with known anti-SARS-CoV-2 nAb titers were used for COVID-globulin production. The manufacturing process included standard ethanol fractionation, chromatographic purification steps, and virus removal or inactivation. Immunoglobulin batches were characterized based on Russian and EU Pharmacopeia guidelines, with the anti-SARS-CoV-2 nAb titers determined using a virus neutralization test (performed in Vero E6 cells) and enzyme-linked immunosorbent assay (ELISA). COVID-globulin safety was assessed by evaluating its toxicity and thrombogenic potential. COVID-globulin protective efficacy was evaluated in immunosuppressed Syrian hamsters via the intraperitoneal administration of COVID-globulin or a placebo Changes in animal body weight and health status were observed daily. Lungs were subjected to macroscopic, histological, and virological studies. The lung virus load was determined using titration of 10% lung tissue homogenate in Vero E6 cells, and the cytopathic effect was visually evaluated.Findings: We produced pure and safe immunoglobulin for intravenous administration, with 98·1±6·5 mg/mL protein content.. The concentration factor of SARS-CoV-2 nAbs in ten COVID-globulin lots was 9·4±1·4 times. Safety studies in animals showed no signs of acute/chronic toxicity or allergenic or thrombogenic properties. COVID-globulin demonstrated protective effects against SARS-CoV-2 in immunosuppressed hamsters. The survival rate in the COVID-globulin groups was 66·6–100% compared with total mortality in the control groups.Interpretation: COVID-globulin, manufactured in accordance with the Ph. Eur. requirements, protected immunosuppressed hamsters against SARS-Cov-2.Funding Information: This work was sponsored and performed by JSC Nacimbio.Declaration of Interests: We declare no competing interests.Ethics Approval Statement: Studies were performed at The National Research Center for epidemiology and Microbiology named after Honorary Academician N.F. Gamaleya of the Ministry of Health of the Russian Federation, after receiving bioethical approval №26 from 08.10.2020 and №28 from 16.11.2020.