Table 1.

Activity and selectivity of L-742,001 in the virus yield and vRNP reconstitution assays^a

Compound	Virus yield assay in MDCK cells				vRNP reconstitution assay in HEK293T cells
	Antiviral activityb		Cytotoxicity (CC50c) at:		Activity (EC50d)	Cytotoxicity (CC50) at 24 h
	EC90	EC99	24 h	72 h
L-742,001	4.3 ± 0.8	6.6 ± 1.3	171 ± 23	62 ± 26	3.8 ± 1.5	255 ± 46
Ribavirin	7.8 ± 0.8	11 ± 1	>400	>400	9.7 ± 1.8	>400

^aData shown are the means ± standard errors of the means (SEM) from at least 3 independent tests.

^bCompound concentration causing a 1-log₁₀ (EC₉₀) or 2-log₁₀ (EC₉₉) reduction in virus yield at 24 h p.i., as determined by real-time RT-PCR.

^cCC₅₀, 50% cytotoxic concentration, as determined by MTS cell viability assay.

^dEC₅₀, 50% effective concentration, i.e., compound concentration producing 50% reduction in vRNP-driven firefly reporter signal, estimated at 24 h after transfection.