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

Yadav, Pragya D; Mendiratta, Sanjeev Kumar; Mohandas, Sreelekshmy; Singh, Arun K; Abraham, Priya; Shete, Anita; Bandyopadhyay, Sanjay; Kumar, Sanjay; Parikh, Aashini; Kalita, Pankaj; Sharma, Vibhuti; Pandya, Hardik; Patel, Chirag G; Patel, Mihir; Soni, Swagat; Giri, Suresh; Jain, Mukul

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.