Table 2. DSM265 activity against P. falciparum parasites at different stages in the life cycle.

Data represent EC50 values unless otherwise stated to be the minimum parasiticidal concentration (MPC).

AssayMPC or EC50
(μg/ml)
Fraction unbound
in assay media
Unbound MPC or
EC50 (μg/ml)
Blood-stage: P. falciparum 3D7 in vitro MPC (kill assay)0.014*0.170.0020
SCID mouse in vivo MPC (plasma)1.10.001§0.0011
Blood-stage: P. falciparum 3D7 in vitro growth assay0.0046*0.170.00078
Liver-stage: P. falciparum to schizont0.00570.2150.0012
P. falciparum early-stage gametocytes stages III to IV; strain NF54>0.420.004>0.0017
Gametocyte assay P. falciparum stages IV to VInactive >16NDND
P. falciparum dual gamete formation assayInactive >42NDND
P. falciparum stage V oocyst38% at 1.00.001§38% at 0.001

*Data taken from Fig. 2D.

†AlbuMAX II (0.5%) in RPMI 1640.

‡Blood to plasma ratio in the humanized SCID mouse of 0.5 was used to convert blood concentrations to plasma concentrations.

§Human plasma.

¶Fetal calf serum (10%) in Dulbecco’s modified Eagle’s medium or similar medium.

∥Human serum (10%) in RPMI 1640.