DSM502 is a pyrrole-based Dihydroorotate Dehydrogenase (DHODH) inhibitor. DSM502 exhibits nanomolar potency againsts Plasmodium DHODH and Plasmodium parasites, with no inhibition of mammalian DHODHs[1].
DSM502 shows inhibitory activity against P. falciparum DHODH (PfDHODH, IC50=20 nM), P. vivax DHODH (PvDHODH, IC50=14 nM) and Pf3D7 cells (EC50=14 nM), with no inhibition of the human enzyme[1].
DSM502 (10 and 50 mg/kg; p.o. once daily for 4 days) results in 97% parasite clearance in confirmatory SCID study compared to 85% clearance in the GSK study[1].DSM502 (18.3 and 50 mg/kg; a single p.o.) exhibits high oral bioavailability (>100%, >100%), apparent t1/2 (2.6, 3.6 h) and Cmax (8.4, 42.3 μM) in mice[1].DSM502 (2.8 mg/kg; a single i.v.) exhibits apparent t1/2 (2.8 h), plasma clearance (26.1 mL/min/kg), and Vss (1.2 L/kg) in mice[1].
[1]. Kokkonda S, et, al. Lead Optimization of a Pyrrole-Based Dihydroorotate Dehydrogenase Inhibitor Series for the Treatment of Malaria. J Med Chem. 2020 May 14;63(9):4929-4956.
[2]. 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.