In vitro metabolism of chloroquine: identification of CYP2C8, CYP3A4, and CYP2D6 as the main isoforms catalyzing N-desethylchloroquine formation.

@article{Projean2003InVM,
  title={In vitro metabolism of chloroquine: identification of CYP2C8, CYP3A4, and CYP2D6 as the main isoforms catalyzing N-desethylchloroquine formation.},
  author={Denis Projean and Bruno Baune and Robert Farinotti and Jean Pierre Flinois and Philippe H. Beaune and Anne Marie Taburet and Julie Ducharme},
  journal={Drug metabolism and disposition: the biological fate of chemicals},
  year={2003},
  volume={31 6},
  pages={
          748-54
        }
}
  • D. Projean, B. Baune, J. Ducharme
  • Published 1 June 2003
  • Biology, Medicine, Chemistry
  • Drug metabolism and disposition: the biological fate of chemicals
In humans, the antimalarial drug chloroquine (CQ) is metabolized into one major metabolite, N-desethylchloroquine (DCQ). Using human liver microsomes (HLM) and recombinant human cytochrome P450 (P450), we performed studies to identify the P450 isoform(s) involved in the N-desethylation of CQ. In HLM incubated with CQ, only DCQ could be detected. Apparent Km and Vmax values (mean +/- S.D.) for metabolite formation were 444 +/- 121 microM and 617 +/- 128 pmol/min/mg protein, respectively. In… 

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