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bioRxiv · 10.1101/2021.09.16.460724

ZRC3308 monoclonal antibody cocktail shows protective efficacy in Syrian hamsters against SARS-CoV-2 infection

Yadav, P.·Mendiratta, S. K.·Mohandas, S.·Singh, A. K.·Abraham, P.·Shete, A.·Bandhyopadhyay, S.·Kumar, S.·Parikh, A.·Kalita, P.·Sharma, V.·Pandya, H.·Patel, C. G.·Patel, M.·Soni, S.·Giri, S.·Jain, M.
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Abstract

We have developed a monoclonal antibody (mAb) cocktail (ZRC-3308) comprising of ZRC3308-A7 and ZRC3308-B10 in the ratio 1:1 for COVID-19 treatment. The mAbs were designed to have reduced immune effector functions and increased circulation half-life. mAbs showed good binding affinities to non-competing epitopes on RBD of SARS-CoV-2 spike protein and were found neutralizing SARS-CoV-2 variants B.1, B.1.1.7, B.1.351, B.1.617.2 and B.1.617.2 AY.1 in vitro. The mAb cocktail demonstrated effective prophylactic and therapeutic activity against SARS-CoV-2 infection in Syrian hamsters. The antibody cocktail appears to be a promising candidate for the prophylactic use and for therapy in early COVID-19 cases which have not progressed to severe disease.

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Yadav, P., Mendiratta, S. K., Mohandas, S., Singh, A. K., Abraham, P., Shete, A., Bandhyopadhyay, S., Kumar, S., Parikh, A., Kalita, P., Sharma, V., Pandya, H., Patel, C. G., Patel, M., Soni, S., Giri, S., Jain, M.. 2021-09-17. ZRC3308 monoclonal antibody cocktail shows protective efficacy in Syrian hamsters against SARS-CoV-2 infection. https://doi.org/10.1101/2021.09.16.460724

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