In vitro selection predicts malaria parasite resistance to dihydroorotate dehydrogenase inhibitors in a mouse infection model

Sci Transl Med. 2019 Dec 4;11(521):eaav1636. doi: 10.1126/scitranslmed.aav1636.


Resistance has developed in Plasmodium malaria parasites to every antimalarial drug in clinical use, prompting the need to characterize the pathways mediating resistance. Here, we report a framework for assessing development of resistance of Plasmodium falciparum to new antimalarial therapeutics. We investigated development of resistance by P. falciparum to the dihydroorotate dehydrogenase (DHODH) inhibitors DSM265 and DSM267 in tissue culture and in a mouse model of P. falciparum infection. We found that resistance to these drugs arose rapidly both in vitro and in vivo. We identified 13 point mutations mediating resistance in the parasite DHODH in vitro that overlapped with the DHODH mutations that arose in the mouse infection model. Mutations in DHODH conferred increased resistance (ranging from 2- to ~400-fold) to DHODH inhibitors in P. falciparum in vitro and in vivo. We further demonstrated that the drug-resistant parasites carrying the C276Y mutation had mitochondrial energetics comparable to the wild-type parasite and also retained their fitness in competitive growth experiments. Our data suggest that in vitro selection of drug-resistant P. falciparum can predict development of resistance in a mouse model of malaria infection.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Dihydroorotate Dehydrogenase
  • Disease Models, Animal
  • Drug Resistance / drug effects
  • Enzyme Inhibitors / chemistry
  • Enzyme Inhibitors / pharmacology
  • Enzyme Inhibitors / therapeutic use*
  • Female
  • Malaria, Falciparum / drug therapy*
  • Malaria, Falciparum / parasitology*
  • Mice, SCID
  • Oxidoreductases Acting on CH-CH Group Donors / antagonists & inhibitors*
  • Oxidoreductases Acting on CH-CH Group Donors / genetics
  • Oxidoreductases Acting on CH-CH Group Donors / metabolism
  • Parasites / drug effects
  • Parasites / enzymology*
  • Phenotype
  • Plasmodium falciparum
  • Point Mutation / genetics
  • Pyrimidines / chemistry
  • Pyrimidines / pharmacology
  • Pyrimidines / therapeutic use
  • Triazoles / chemistry
  • Triazoles / pharmacology
  • Triazoles / therapeutic use


  • Dihydroorotate Dehydrogenase
  • Enzyme Inhibitors
  • Pyrimidines
  • Triazoles
  • DSM265
  • Oxidoreductases Acting on CH-CH Group Donors