Table 1. IC50s from neutralization of authentic SARS-CoV-2 VOCs and fold-reduction in neutralization efficacy compared with WA1 variant.

	IC50 WA1	SEM WA1	IC50 B.1.351	SEM B.1.351	IC50 B.1.617.2	SEM B.1.617.2	IC50 BA.1	SEM BA.1	IC50 B.1.351 foldΔ from WA1	IC50 B.1.617.2 foldΔ from WA1	IC50 BA.1 foldΔ from WA1
Group 1	2589	993	835	461	879	437	66	28	3.1	2.9	39.0
Group 2	1637	196	1091	384	763	153	80	20	1.5	2.1	20.4
Group 3	2321	756	231	84	404	99	10	4	10.0	5.7	223.4
Group 4	2364	1136	616	357	864	518	6	4	3.8	2.7	379.5

IC50s were derived from neutralization curves in Figs 4–6. IC50s were determined by nonlinear curve fit as described in Material and Methods.