DSM705 hydrochloride, an orally active antimalarial compound, is a pyrrole-based Dihydroorotate Dehydrogenase (DHODH) inhibitor. DSM705 hydrochloride exhibits nanomolar potency against Plasmodium DHODH and Plasmodium parasites (IC50=95, 52 nM for P. falciparum and P. vivax DHODH, respectively), with no inhibition of mammalian DHODHs[1].
DSM705 hydrochloride shows inhibitory activity against P. falciparum DHODH (PfDHODH, IC50=95 nM), P. vivax DHODH (PvDHODH, IC50=52 nM) and Pf3D7 cells (EC50=12 nM), with no inhibition of the human enzyme[1].
DSM705 (3-200 mg/kg; p.o. twice a day for 6 days) hydrochloride provides the maximum rate of parasite killing at the dose of 50 mg/kg and fully suppresses parasitemia by days 7-8[1].DSM705 (2.6 and 24 mg/kg; a single p.o.) hydrochloride exhibits high oral bioavailability (74%, 70%), apparent t1/2 (3.4, 4.5 h) and Cmax (2.6, 20 μM) in Swiss outbred mice[1].DSM705 (2.3 mg/kg; a single i.v.) hydrochloride exhibits plasma clearance (CL=2.8 mL/min/kg) and Vss (1.3 L/kg) in mice[1].
[1]. Palmer MJ, et, al. Potent Antimalarials with Development Potential Identified by Structure-Guided Computational Optimization of a Pyrrole-Based Dihydroorotate Dehydrogenase Inhibitor Series. J Med Chem. 2021 May 13;64(9):6085-6136.