A broadly neutralising monoclonal antibody overcomes the mutational landscape of emerging SARS-CoV2 variant of concerns

The emergence of new variants of SARS-CoV-2 necessitates unremitting efforts to discover novel therapeutic mAbs. Here, we report an extremely potent mAb named P4A2 that can neutralize all the circulating variants of concerns (VOCs) with high efficiency, including the highly transmissible Omicron. The crystal structure of the P4A2 Fab:RBD complex revealed that the residues of the RBD that interact with P4A2 are part of the ACE2-receptor-binding motif and are not mutated in any of the VOCs. The pan coronavirus pseudotyped neutralization assay confirmed that the P4A2 mAb is specific for SARS-CoV-2 and its VOCs. Passive administration of P4A2 to K18-hACE2 transgenic mice conferred protection, both prophylactically and therapeutically, against challenge with VOCs. Overall, our data shows that, the P4A2 mAb has immense therapeutic potential to neutralize the current circulating VOCs and will be highly effective against future variants as well due to its unique mode of binding.