Table 4

IC₅₀s of recombinant neuraminidases tested in the fluorescent NI assay

NA substitution	Mean IC₅₀ ± SD^{^a} [nM (fold^{^b})]
NA substitution	Zanamivir	Oseltamivir	Peramivir	Laninamivir
E119V	0.54 ± 0.13 (3)	44.93 ± 3.76 (281)	0.12 ± 0.02 (1)	0.43 ± 0.08 (4)
T148I	1.33 ± 0.16 (6)	0.04 ± 0.00 (1)	0.06 ± 0.00 (1)	0.34 ± 0.02 (3)
E119V, T148I	220.48 ± 14.00 (1,050)	984.62 ± 76.60 (6,154)	9.54 ± 1.67 (119)	79.47 ± 10.30 (722)
None	0.21 ± 0.03	0.16 ± 0.07	0.08 ± 0.01	0.11 ± 0.04

↵a Based on at least three independent experiments.
↵b Fold change based on comparison to the respective IC₅₀ values of recNA E119 and T148 (wild type).