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Volume 14, Number 5—May 2008

Declining Artesunate-Mefloquine Efficacy against Falciparum Malaria on the Cambodia–Thailand Border

Chansuda Wongsrichanalai*Comments to Author  and Steven R Meshnick†
Author affiliations: *US Naval Medical Research Unit No. 2, Jakarta, Indonesia; †University of North Carolina at Chapel Hill School of Public Health, Chapel Hill, North Carolina, USA

Main Article


Studies that demonstrated poor artesunate-mefloquine efficacy, Cambodia–Thailand border*

Reference Study site, country, y ACT No. patients Follow-up duration, d Efficacy, %
Denis et al., 2006 (5) Pailin, Cambodia, 2002 ATS ≈12 mg/kg in 2 doses on days 0, 1, and 2 + MFQ ≈20 mg/kg in 2 doses on day 0 70 children 
and adults 28 85.7 (PCR-corrected)
Vijaykadga et al., 2006 (6) Trat, Thailand, 2003 ATS 12 mg/kg (maximum 600 mg) in 2 doses on days 0 and 1 + MFQ 25 mg/kg (maximum 1,250 mg) in 2 doses on day 0 44, age >10 y, mostly adults 28 78.6
Denis et al., 2006 (5)† Pailin, Cambodia, 2004 ATS 12 mg/kg in 2 doses on days 0, 1, and 2 + MFQ 25 mg/kg in 2 doses on day 0 58 children 
and adults 42 79.3 (PCR-corrected)

*ACT, artemisinin-based combination therapy; ATS, artesunate; MFQ, mefloquine; day 0, first 24 h of enrollment and start of therapy.
†Also in this study, increased copy numbers of Plasmodium falciparum multidrug resistance 1 gene were found to be associated with parasite recrudescence, and as many as 44% of patients did not clear parasites until after 48 hours.

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