December 16th 2022

Published in Nature Micobiology: a new monoclonal antibody neutralizing SARS-CoV-2 Omicron variants

Published in Nature Micobiology: a new monoclonal antibody neutralizing SARS-CoV-2 Omicron variants 

The CARE partner Centre Hospitalier Universitaire Vaudois (CHUV) isolated a monoclonal antibody (mAb) named P2G3 that does not lose activity towards Omicron BA.1 and BA.2 compared to other variants of concern (VOC) (Wild Type, Alpha, Beta and Delta) and is more potent than other current clinically authorized and/or clinically advanced mAbs in vitro.

The collaboration within CARE with the Vaccine Research Institute (Inserm-VRI, France), the French Alternative Energies and Atomic Energy Commission (CEA) and KU Leuven (KUL, Belgium) led to an extended characterisation of P2G3 in vitro and in vivo and gave some insight on why this mAb is a promising anti-Omicron drug. Indeed, P2G3 alone, or in combination with P5C3 (a broadly active Class 1 mAb previously identified; Fenwick et al, 2021), confers complete prophylactic or therapeutic protection in vivo.

P2G3 is a Class 3 mAb that recognizes an epitope on the receptor binding domain (RBD) different from those bound by all other therapeutic mAbs authorized or at an advanced stage of development. The binding epitope is largely non-overlapping with residues mutated in Omicron, a unique feature. Furthermore, the emerging Omicron BA.4 and BA.5 variants with RBD mutations L452R and F486V are distant from the P2G3 binding epitope and unlikely to impact neutralizing activity.

In a context where the emergence of the the Delta and Omicron variants reduced the efficacy of vaccines and potent neutralizing mAbs, leaving vulnerable populations such as immunocompromised individuals without protection, the broadly active combination of P2G3 and P5C3 has the potential to be a superior anti-SARS-CoV-2 mAb cocktail for prophylactic and therapeutic interventions against all current VOCs, and its breadth of activity suggests that it might be capable of neutralizing many future SARS-CoV-2 VOCs.

To learn more, click here: Patient-derived monoclonal antibody neutralizes SARS-CoV-2 omicron variants and confers full protection in monkeys.