PfKRS1 inhibitor 5

LysRs-IN-2 is a lysyl-tRNA synthetase (KRS) inhibitor with IC50s of 0.015 μM and 0.13 μM for Plasmodium falciparum lysyl-tRNA synthetase (PfKRS) and Cryptosporidium parvum lysyl-tRNA synthetase (CpKRS), respectively[1].

Research Areas >> Infection

IC50: 0.015 μM (PfKRS), 0.13 μM (CpKRS)[1]

LysRs-IN-2 is active against whole-cell bloodstream P. falciparum 3D7 (EC50 = 0.27 μM), HsKRS (IC50 = 1.8 μM), HepG2 cells (EC50 = 49 μM), and Cryptosporidium parvum (EC50 = 2.5 µM)[1].

LysRs-IN-2 (1.5 mg/kg; orally once a day for 4 days) reduces parasitemia by 90% in the murine P. falciparum SCID model. LysRs-IN-2 (20 mg/kg; orally once a day for 7 days) reduces parasite shedding in NOD SCID gamma mice and INF-γ-knockout mice (Cryptosporidium mouse models)[1]. Animal Model: Murine P. falciparum NODscidIL2Rγnull (SCID) model[1] Dosage: 1.5 mg/kg Administration: Orally once a day for 4 days Result: Reduced parasitemia by 90% in the malaria SCID mouse model. Animal Model: NOD SCID gamma and INF-γ–knockout mouse models (Cryptosporidium mouse models)[1] Dosage: 20 mg/kg Administration: Orally once a day for 7 days Result: Reduced parasite shedding below detection level, and this reduction was sustained for 3 wk after treatment had stopped in INF-γ-knockout mice. Dosed orally at a concentration of 20 mg/kg once a day for 7 days showed 96% reduction of parasite shedding comparable to paromomycin in NOD SCID gamma mice.

[1]. Baragaña B, et al. Lysyl-tRNA synthetase as a drug target in malaria and cryptosporidiosis. Proc Natl Acad Sci U S A. 2019 Apr 2;116(14):7015-7020.