The activity of raltegravir and 4 other integrase inhibitors (MK-2048, L870,810,
IN2, and IN5) was investigated in primary human macrophages, PBMC and
C8166-lymphocytic T cells, in order to determine their relative potency and
efficacy in different cellular systems of HIV infection. Raltegravir showed
better protective efficacy in all cell types; MK-2048, L870,810 and IN5 showed a
potent anti-HIV-1 activity in macrophages, while in lymphocytes only MK-2048 and
L870,810 showed an inhibitory effect comparable to raltegravir. IN2 was a poorly
effective anti-HIV-1 compound in all cellular systems. All effective integrase
inhibitors exhibited a potent antiviral activity against both X4 and R5 HIV-1
strains. In general, raltegravir, MK-2048, L870,810 and IN5 showed anti HIV
activity similar or slightly higher in macrophages compared to PBMC and C8166 T
cells: for MK-2048, the EC(50) was 0.4, 0.9, 11.5nM in macrophages, in PBMCs and
T cells, respectively; for L870,810, the EC(50) was 1.5, 14.3, and 10.6nM,
respectively; for IN5 the EC(50) was 0.5, 13.7, and 5.7nM, respectively
