Previous Article | Next Article ![]()
Antimicrobial Agents and Chemotherapy, December 2008, p. 4400-4406, Vol. 52, No. 12
0066-4804/08/$08.00+0 doi:10.1128/AAC.00673-07
Copyright © 2008, American Society for Microbiology. All Rights Reserved.

Department of Child Health, Korle Bu Teaching Hospital, Accra, Ghana,1 Department of Clinical Pharmacology, Astra Zeneca Ltd., Lund, Sweden,2 Centre for Medical Parasitology at the Department of Clinical Microbiology and Department of Infectious Diseases, Copenhagen University Hospital (Rigshospitalet), and Department of International Health, Immunology, and Microbiology, University of Copenhagen, Copenhagen, Denmark3
Received 23 May 2007/ Returned for modification 15 October 2007/ Accepted 30 August 2008
Artesunate (AS) is used in combination with amodiaquine (AQ) as first-line treatment for uncomplicated malaria in many countries. We investigated the effect of concomitant AS administration on the pharmacokinetics of AQ and compared concentrations of desethylamodiaquine (DEAQ), the main metabolite of AQ, in plasma between patients with different variants of the cytochrome P4502C8 (CYP2C8) gene. A two-compartment model was fitted to 169 plasma DEAQ concentrations from 103 Ghanaian children aged 1 to 14 years with uncomplicated malaria treated either with AQ alone (n = 15) or with AS plus AQ (n = 88). The population clearance of DEAQ appeared to increase nonlinearly with body weight, and the central volume of distribution of DEAQ was higher (P < 0.001) in the AS-plus-AQ group than in the AQ-only group. The maximum plasma DEAQ concentration was higher (P < 0.001), and the population distribution half-life was shorter (P < 0.01), in the AQ-only group than in the AS-plus-AQ group. The total areas under the plasma DEAQ concentration-time curves (P = 0.68) and elimination half-lives (P = 0.39) were similar for the two groups. There was a high frequency (0.179) of the non-wild-type allele of CYP2C8, but no differences between CYP2C8 genotypes with regard to AQ efficacy or safety were evident. The sample size, however, was limited, so monitoring of AQ toxicity in the study area is still indicated. The nonlinear clearance of DEAQ and the wide variability in kinetic parameters have safety implications for weight-based dosing of higher-body-weight children with AQ. The pharmacokinetics of artemisinin combination therapies should be studied in malaria patients, because the rapid parasite clearance caused by the artemisinin may affect the kinetics of the partner drug and the combination.
Published ahead of print on 8 September 2008.
Copyright © 2009 by the American Society for Microbiology. For an alternate route to Journals.ASM.org, visit: http://intl-journals.asm.org | More Info»