TABLE 2.

In vitro IC₅₀s and IC₉₀s of racemic and enantiomeric PZQ and 4-OH metabolites against NTS at 72 h postincubation

Compound	IC50 (μg/ml) at 72 h	IC90 (μg/ml) at 72 h	Eudysmic ratio
Rac-PZQ	1.5	34.5
R-PZQ	0.03	18.8	1,196
S-PZQ	40.0	522a
Rac-trans-4-OH-PZQ	133a	5,852a
R-trans-4-OH-PZQ	28.5	747
S-trans-4-OH-PZQ	NAb	NA
Rac-cis-4-OH-PZQ	911a	2,448,837a
R-cis-4-OH-PZQ	34.3	1,161a
S-cis-4-OH-PZQ	NA	NA

^aExtrapolated value determined by CompuSyn.

^bNA, not active at 100 μg/ml.