TABLE 2.

Ex vivo drug susceptibility of P. falciparum laboratory strains to CQ and CQRRAs

Drug or drug combination	FC27a		3D7a		K1b		W2b
	Median (range) IC50 (nM)c	Fold changed	Median (range) IC50 (nM)c	Fold change	Median (range) IC50 (nM)c	Fold change	Median (range) IC50 (nM)c	Fold change
VP	27,270 (10,280–34.430)		13,640 (13,630–18,380)		28,530 (13,930–48.570)		6,490 (5,820–6,530)
MF	8,962 (8,614–9,774)		3,820 (3,760–3,920)		1,544 (1,309–1,699)		2,600 (2,540–2,610)
L7	12,810 (11,860–24,350)		8,550 (8,430–10,150)		6,466 (5,098–12,372)		5,400 (5,280–5,670)
PQe	NAf		NA		9,599		14,442
CQ	9.3 (8.5–10.8)		6.7 (6.6–7.8)		138.9 (116.9–150.2)		174.6 (173.6–181.0)
CQV (1 μM)	12.8 (11.9–24.3)	0.73	7.3 (6.7–7.6)	0.92	24.6 (20.9–33.1)	5.65	14.6 (14.5–20.2)	11.96
CQM (0.35 μM)	12.1 (11.2–13.9)	0.77	7.8 (6.9–7.9)	0.86	21.9 (14.0–39.3)	6.34	22.9 (22.1–23.7)	7.62
CQL (1.5 μM)	10.8 (10.6–14.9)	0.86	6.9 (6.7–7.6)	0.97	27.2 (14.9–41.9)	5.11	7.7 (7.3–8.2)	22.68
CQPQ (0.5 μM)	7.7 (7.1–7.7)	1.21	11.9 (10.0–20.8)	0.56	86.8 (81.0–96.8)	1.6	120.0 (118.6–138.0)	1.46

^aA chloroquine-sensitive laboratory strain.

^bA chloroquine-resistant laboratory strain.

^cData are derived from three independent experiments unless indicated otherwise.

^dFold change of the median CQ-CQRRA IC₅₀ from the CQ IC₅₀.

^eDerived from one experiment only.

^fNA, not tested in this strain.