Table 3. Viral NA inhibition by oseltamivir carboxylate and zanamivir.
| Virus | Oseltamivir carboxylate | Zanamivir |
|---|---|---|
| IC50 ± SD (nM) | IC50 ± SD (nM) | |
| 292R (n = 6) | 0.19 ± 0.12 | 0.37 ± 0.13 |
| 292K (n = 5) | 2,900 ± 410 | 3.7 ± 1.5 |
Mean concentrations of drugs ± standard deviations that inhibited 50% (IC50) of the viral NA activity in a functional assay with the MUNANA substrate. 292R = arginine at NA residue 292. 292K = lysine at NA residue 292. Values were calculated on duplicates of six wild type (292R) and five mutated (292K) viral samples.