Abstract
Background There is a critical need for effective therapies that are immediately available to control the spread of COVID-19 disease. In this study, we assessed currently marketed intravenous immunoglobulin (IVIG) products for antibodies against human common coronaviruses that may cross-react with the SARS-CoV-2 virus.
Methods Gamunex®-C and Flebogamma® DIF (Grifols) IVIG were tested against several betacoronaviruses antigens using ELISA techniques: HCoV (undetermined antigen), HCoV-HKU1 (N protein), SARS-CoV (culture lysate), MERS-CoV (N protein; S1 protein/RBD; S protein), and SARS-CoV-2 (S1 protein).
Results Both IVIG products showed consistent reactivity to components of the tested viruses. Positive cross-reactivity was seen in SARS-CoV, MERS-CoV, and SARS-CoV-2. For SARS-CoV-2, positive reactivity was observed at IVIG concentrations ranging from 100 μg/mL with Gamunex-C to 1 mg/mL with Flebogamma 5% DIF.
Conclusion Gamunex-C and Flebogamma DIF IVIG contain antibodies reacting against SARS-CoV-2 antigens. These preparations may be useful for immediate treatment of COVID-19 disease.
Competing Interest Statement
The authors are full-time employees of Grifols, the manufacturer of Gamunex-C and Flebogamma DIF.
Footnotes
A mistake has been corrected in the section "IVIG Products": 50 mg/mL and 100 mg/mL instead of 5 mg/mL and 10 mg/mL IgG concentrations.