Rising anti-SARS-CoV-2 titer in a human immunoglobulin preparation

Abstract

Aims: To assess potential changes of pharmacological activities of a novel normal immunoglobulin for intravenous administration from pooled normal plasma (IVIG). Methods: We assessed the impact of the SARS-CoV-2 pandemic on the level and activity of pathogen-specific antibodies in IVIG batches produced before and during the pandemic. Antibody levels were determined by immunoassays. The functional activity of SARS-CoV-2 antibodies was determined by in vitro neutralization. Results: In the IVIG, the antibody titer against bacteria, different viruses and a fungus were found to be in a defined range, whereas titers to common pathogens remained consistent over time, the level of antibodies to SARS-CoV-2 have increased within two years after onset of the pandemic to levels comparable to a hyperimmunoglobulin preparation. These antibodies could neutralize SARS-CoV-2 and cross-react with other coronaviruses. Conclusion: Increasing titers of SARS-CoV-2 antibodies might be beneficial for special vulnerable patient groups.