Table 2. Antiviral activity of mCD4.2, mCD4.3 and mCD4-conjugates in comparison with mAb VRC01, b12 and the NNRTI dapivirine.

Viral strains	Clade-tropism	mCD4.2 (nM)	mCD4.2 PS1(nM)	mCD4.3 (nM)	mCD4.3PS1 (nM)	mAb VRC01 (nM)	mAb b12 (nM)	TMC120 Dapivirine (nM)
VI820	A-X4R5	6.1	0.031	4.2	0.024	12	>100	2
Bal	B-R5	2	0.035	2.3	0.031	0.64	1	1.7
IIIB	B-X4	0.22	0.0073	0.16	0.0025	0.64	0.09	0.84
MN	B-X4	0.59	0.046	0.37	0.026	2	1.5	1.5
SF162	B-R5	1.3	0.01	0.66	0.0075	5.2	0.36	1.3
SHIV162P3	B-R5	69	2.2	29	1.4	8.2	6	>1000
pREJO.c/2864 cl2	T/F B-R5	76	0.28	46	0.28	0.77	>100	1.6
pTHRO.c/2626	T/F B-R5	19	8.9	15	6.4	>100	35	1.9
pWITO.c/2474	T/F B-R5	184	1.3	178	1.5	2	>100	1.1
VI829	C-R5	512	4	221	3.6	9.3	>100	1.3
P246F10	T/F C-R5	718	58	510	33	85	>100	1.4
pZM247Fv2	T/F C-R5	>1000	206	>1000	192	5.7	>100	2.3
VI824	D-R5	56	0.68	39	0.7	>100	>100	1.2
VI1888 (CRF01)	AE-R5	5382	1064	4509	1212	16	80	2.1
Ca10-3 (CRF01)	AE-X4	4.7	0.12	3.1	0.076	13	>100	1.2
MP568 (CRF02)	AG-R5	155	4.9	204	4.2	54	>100	1.1
CC50		24036	>50000	15540	>50000	>100	>300	2524

Various replication competent HIV-1 or SHIV162P3 viruses at 10⁻³ MOI were incubated with a range of concentrations of the indicated compounds and TZM-bl cells for 48 h. Infection was determined as explained in the methods section. IC₅₀ values (expressed in nM) represent the mean of at least 2 independent experiments, each with triplicate measurements and were calculated in GraphPad Prism 5.03 using non-linear regression. (T/F transmitted founder virus; X4: CXCR4 tropic; R5: CCR5 tropic, IC₅₀: 50% inhibitory concentration; CC₅₀: 50% cytotoxic concentration).