Table 2.

IC₅₀ values (i.e. concentrations required to reduce parasite proliferation by 50%) for growth inhibition of the spiroindolone-resistant parasite line NITD609-R^Dd2-clone#2 and its Dd2 parental line⁷ by the eleven Pathogen Box compounds of interest, the spiroindolone KAE609, and the non-PfATP4-associated antimalarial drugs chloroquine and artemisinin.

Compound	IC50 (µM) for inhibition of parasite proliferation
	Dd2 parent	NITD609-RDd2-clone#2	Fold difference	n	p
MMV000858	0.38 ± 0.02	2.94 ± 0.38	7.7 ± 0.1	4	<0.001
MMV001059	0.72 ± 0.06	3.74 ± 0.31	5.2 0.1	5	<0.001
MMV006239	0.24 ± 0.03	1.87 ± 0.17	7.8 ± 0.1	4	<0.001
MMV020081	0.11 ± 0.01	0.42 ± 0.03	3.8 ± 0.1	5	<0.001
MMV020136	0.52 ± 0.02	3.92 ± 0.28	7.6 ± 0.1	4	<0.001
MMV020391	0.28 ± 0.02	2.76 ± 0.32	9.9 ± 0.1	4	<0.001
MMV020520	0.32 ± 0.04	1.39 ± 0.15	4.3 ± 0.2	4	<0.001
MMV020623	0.37 ± 0.03	2.12 ± 0.31	5.7 ± 0.2	4	0.001
MMV020710	0.098 ± 0.012	0.55 ± 0.03	5.6 ± 0.1	4	<0.001
MMV085210	1.60 ± 0.07	6.8 ± 0.9	4.2 ± 0.1	4	<0.001
MMV688980	1.12 ± 0.07	7.2 ± 0.6	6.4 ± 0.1	5	<0.001
KAE609	0.0011 ± 0.0001	0.012 ± 0.001	11.6 ± 0.1	5	<0.001
Chloroquine	0.21 ± 0.02	0.22 ± 0.02	1.0 ± 0.1	6	0.8
Artemisinin	0.017 ± 0.005	0.019 ± 0.005	1.1 ± 0.4	3	0.8

The IC₅₀ values are averaged from those obtained in n experiments and are presented as mean ± SEM. The ‘fold difference’ is the IC₅₀ value obtained for NITD609-R^Dd2-clone#2 divided by the IC₅₀ value obtained for the Dd2 parent (shown as the mean ± SEM from the number of experiments indicated). The p values are derived from unpaired student t tests.