Table 1.

IC₅₀s and IC₉₀s obtained with different in vitro assays

Assay	IC50a/IC90b (nM)				P value for MV HRC2 vs MV HRC4
	MV HRC1	MV HRC2	MV HRC3	MV HRC4
Plaque reduction	6,941/>10,000	2.03/26.6	285/2,837	<1/2.7	0.0016
Spreading	∼2,132	56.91	∼2,286	56.71
Fusion at 2 h	58.44	<1	68.57	<1
Fusion at 4 h	1,992	15.57	381.5	<1
Fusion at 6 h	2,088/>10,000	580/2,259	2,305/2,768	1.05/3.2	<0.0001
Ex vivo culture	ND	9.38	ND	10.07

^aThe IC₅₀s of MV HRC1, HRC2, HRC3, and HRC4 were determined by entry, spreading, fusion, and ex vivo assays.

^bThe IC₉₀ was calculated when the IC₅₀ could not be determined. Statistical comparisons of MV HRC2 and HRC4 fits were performed with the F test.