To evaluate the in vivo antiviral efficacy of IBP-CP24 and CP24 against HIV-1 JR-CSF infection in humanized mice, we first evaluated the in vitro inhibitory activity of IBP-CP24 and CP24 against infection of HIV-1 JR-CSF (a CCR5-tropic strain commonly used for infection of humanized mice) in TZM-bl cells. This evidence concerns the gene CYP24A1 and infection.