Figure 4: AN3661 susceptibility of drug-pressured P. falciparum parasites.

(a) Selection process of W2 and Dd2 parasites subjected to AN3661 at either a single concentration or increasing concentrations over time. (b) Susceptibility to AN3661 of W2-strain wild-type (WT) and drug-pressured lines (replicates: WT, 13; W2-R1, 6; W2-R3, 3; W2-R3^rev, 3; W2-R4, 6; W2-R4^rev, 3; W2-R5, 2; W2-R5^rev, 3). (c) Susceptibility to AN3661 of Dd2 strain WT and drug-pressured lines (replicates: WT, 27; Dd2-Ra, 9; Dd2-Rb, 11; Dd2-Rc, 3; Dd2-R1, 3; and Dd2-R2, 3). For all assays, details are in Supplementary Table 1, bar graphs represent mean±s.e.m. IC₅₀ values, and pfmdr1 copy numbers are indicated for each parasite line. Significance was determined using a two-tailed unpaired t-test, comparing drug-pressured parasites to parental strains, unless otherwise indicated. *P<0.05, **P<0.005, ***P<0.001, ****P<0.0001. n.s., not significant (P>0.05); n.d., not determined.