Volume 76, Issue 4
  • ISSN: 0002-9637
  • E-ISSN: 1476-1645


Artemisinin combination therapies (ACTs) have recently been adopted as first-line therapy for infections in most malaria-endemic countries. In this study, we estimated the association between artesunate-mefloquine therapy failure and genetic changes in the putative transporter, . Blood samples were acquired from 80 patients enrolled in an 2004 efficacy study in Pailin, Cambodia, and genotyped for copy number and haplotype. Having parasites with three or more copies of before treatment was strongly associated with recrudescence (hazard ratio [HR] = 8.30; 95% CI: 2.60–26.43). This relationship was maintained when controlling for initial parasite density and hematocrit (HR = 7.91; 95% CI: 2.38–26.29). Artesunate-mefloquine treatment selected for increased copy number, because isolates from recurrent episodes had higher copy numbers than the paired enrollment samples (Wilcoxon rank test, = 0.040). copy number should be evaluated further as a surveillance tool for artesunate-mefloquine resistance in Cambodia.


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  • Received : 12 Sep 2006
  • Accepted : 01 Jan 2007

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