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bioRxiv · 10.1101/2022.02.21.481341

Potent Neutralizing Activity of Polyclonal Equine Antibodies against Omicron SARS-CoV-2

Luczkowiak, J.·Radreau, P.·Nguyen, L.·Labiod, N.·Lasala, F.·Herbreteau-Delale, C.·Delgado, R.
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Abstract

Using a polyclonal approach of equine anti-SARS-CoV-2 F(ab)2 antibodies we have achieved a high level of neutralizing potency against all SARS-CoV-2 variants tested. Neutralization titers were in the range of 105-106 IU/mL including Omicron: 111,403 UI/mL, which is 2-3 orders of magnitude what is normally achieved in response to SARS-CoV-2 infection and/or vaccination. The presence of high titers of a repertoire of antibodies targeting conserved epitopes in different regions of the spike protein could plausibly account for this remarkable breadth of neutralization. These results warrant the clinical investigation of anti-SARS-CoV-2 equine polyclonal F(ab)2 antibodies as a novel therapeutic strategy against COVID-19

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Luczkowiak, J., Radreau, P., Nguyen, L., Labiod, N., Lasala, F., Herbreteau-Delale, C., Delgado, R.. 2022-02-23. Potent Neutralizing Activity of Polyclonal Equine Antibodies against Omicron SARS-CoV-2. https://doi.org/10.1101/2022.02.21.481341

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