Clinical application of SARS-CoV-2 antibody detection and monoclonal antibody therapies against COVID-19

Table 3 Sensitivity of Omicron variants to therapeutic monoclonal antibodies

mAb (s)	FDA EUA	Target on S	Omicron variant
			BA.1	IC50	BA.2	IC50
Bamla/Etese	Yes	BRD or S	Reduction in activity vs control approximately 1000-fold (highly resistant)	> 10000 ng/mL	Reduction in activity vs control approximately 1000-fold (highly resistant)	> 10000 ng/mL
Casir/Imdev	Yes	BRD	Reduction in activity vs control approximately 1000-fold (highly resistant)	> 10000 ng/mL	Reduction in activity vs control approximately 1000-fold (highly resistant)	> 10000 ng/mL
Sotro	Yes	BRD	Median fold reduction in susceptibility 4.0 (IQR: 2.6 to 6.9)	Median 276 ng/mL (IQR: 163 to 423)	Median fold reduction in susceptibility 17 (IQR: 13 to 30)	Median 1250 ng/mL (IQR: 567 to 1456)
Cilag/Tixag	Yes	BRD	Median fold reduction in susceptibility 86 (IQR:27 to 151). The FDA recommended that the dosage for each mAb in this combination be increased 300 mg and administered intramuscularly	Median 256 ng/mL (IQR: 170 to 750)	Median fold reduction in susceptibility 5.4 (IQR: 3.7 to 6.9). Nearly complete restoration BA.2 susceptibility to cilgavimab	Median 44 ng/mL (IQR: 27 to 73)
Bebte	Yes	BRD	Median fold reduction in susceptibility 1.0 (IQR: 0.7 to 1.4) Bebtelovimab is the only mAb active against the current dominant circulating Omicron variant; in non- hospitalized adults, bebtelovimab may be used as an alternative therapy when no preferred therapy (e.g., nirmatrelvir/ritonavir, remdesivir) available	Median 2.6 ng/mL (IQR: 1.8 to 5.0)	Median fold reduction in susceptibility 1.0 (IQR: 0.7 to 1)	Median 4.0 ng/mL (IQR: 0.8 to 5.0)
Regda	No	BRD	Displayed little residual activity	NA	Displayed little residual activity	NA
Amuba	No	BRD	Displayed little residual activity	NA	Displayed little residual activity	NA
Romlu	No	BRD	Retained partial activity	NA	Displayed little residual activity	NA
Adint	No	BRD	Retained partial activity	NA		NA

Adint: Adintrevimab; Amuba: Amubarvimab; Bamla/Etese: Bamlanivimab/Etesevimab; Bebte: Bebtelovimab; BRD: Spike receptor binding domain; Casir/Imdev: Casirivimab/Imdevimab; Cilag/Tixa: Cilgavimab/Tixagevimab; EUA: Emergency use authorization; FDA: United States Food and Drug Administration; IC₅₀: 50% inhibitory concentration; IQR: Interquartile range; mAbs: Monoclonal antibodies; NA: Not available; Regda: Regdanvimab; Romlu: Romlusevimab; S: Spike protein; Sotro: Sotrovimab.