Table 2.
Comparison of the susceptibility of the culture-adapted P. knowlesi A1-H.1 line with a recent Malaysian P. knowlesi isolate, UM01.
| Compound | a UM01 (macaque RBC) EC50 (nM) (range/2) | b A1-H.1 (human RBC) EC50 (nM) ± SEM | Fold difference (A1-H.1/UM01) |
|---|---|---|---|
| Endoperoxides | |||
| Dihydroartemisinin | 2.1 (0.4) | 2.0 ± 0.3 | 0.95 |
| Artesunate | 13.8 (3.6) | 10.9 ± 1.7 | 0.79 |
| Artefenomel (OZ439) | 4.4 (1.6) | 6.6 ± 1.4 | 1.5 |
| Quinolines and amino-alcohols | |||
| Chloroquine | 21.5 (4.9) | 29.3 ± 4.7 | 1.36 |
| Mefloquine | 13.1 (2.5) | 10.9 ± 1.7 | 0.83 |
| Quinine | 40.3 (0.4) | 54.8 ± 3.0 | 1.36 |
| Ferroquine | 9.8 (2.32) | 12.2 ± 1.6 | 1.24 |
| Dihydrofolate reductase inhibitors | |||
| Pyrimethamine | 3.2 (0.5) | 5.1 ± 0.8 | 1.59 |
| Cycloguanil | 0.7 (0.1) | 1.3 ± 0.3 | 1.86 |
| Trimethoprim | 137 (54) | 265 ± 47 | 1.93 |
| P218 | 0.68 (0.04) | 4.1 ± 0.7 | 6.03 |
| Other | |||
| Atovaquone | 4.1 (0.04) | 2.6 ± 0.4 | 0.63 |
| Pyronaridine | 4.9 (0.84) | 10.7 ± 1.6 | 2.18 |
| DSM265 | 170 (66) | 303 ± 15 | 1.78 |
| DSM421 | 142 (71) | 194 ± 23 | 1.37 |
| Cipargamin (KAE609) | 3.8 (1.6) | 6.1 ± 0.5 | 1.61 |
| PA21A092 | 35.7 (2.8) | 63.8 ± 7.6 | 1.79 |
| AN13762 | 3618 (110) | 2762 ± 296 | 0.76 |
Parasites were exposed to the compounds for a single life cycle (27 h).
a
UM01 data are the mean of two independent experiments each performed in duplicate. The range/2, calculated for the two experiments, is shown in parentheses.
b
Data reported previously (van Schalkwyk et al., 2017) or from Table 1 above. Data are the mean ± SEM for at least three experiments each performed in duplicate.