TABLE 2.

Sensitivities of different HIV-1 group O proteases to indinavir and saquinavir using the lambda-based phenotypic method and the standard in vitro drug susceptibility assay

MethodSample (mutation pattern)IC50 (nM) (fold increase) of:
IndinavirSaquinavir
Lamda phageHXB2 (WTa)25 ± 22.57 ± 0.88
ESP2-0 (WT)28 ± 5.755.08 ± 0.41
ESP2-4 (L10V, G48M, F53L, 154V)150 ± 32.25 (5,4)122.67 ± 39.5 (24)
Standard cell culture assayHXB2NDbND
ESP1-2 (WT)15.135 ± 0.78
ESP2-3 (L10V, G48M, F53L, 154V)185.5 ± 53.5 (12)1,264.7 ± 285 (> 200)
  • a WT, wild type.

  • b ND, not done.