A human antibody derived from original SARS-CoV-2 infection effectively neutralizes omicron

SARS-CoV-2 (Severe acute respiratory syndrome coronavirus 2) Variants of Concern (VOCs), such as the Omicron sub-variants, present significant challenges in pandemic control due to their capacity to escape antibodies and breach vaccine protections. Discovering antibodies that can tolerate mutations in VOCs and understanding their underlying mechanisms is crucial for developing therapeutics for COVID-19 patients, particularly those for whom other therapies may be unsuitable. Here, we report the neutralization of the Omicron variant by FD20, a broadly active human monoclonal antibody. In contrast to a clinically approved control antibody, FD20 neutralizes Omicron with comparable IC₅₀ values to those observed for previously circulating VOCs and the original strain reported in Wuhan. Leveraging structural information, we provide insights into its resilience against mutations in Omicron. The results encourage the prospective development of FD20 as a therapeutic option for COVID-19 caused by current and potentially future VOCs.