Research news: September 2009
N Engl J Med 2009;361:455-67
Artemisinin is the first line treatment of uncomplicated falciparum malaria in areas where malaria is endemic, but evidence is emerging that the parasite is becoming resistant to this drug at the Thai-Cambodian border. This is the site where, in the 1950s and 1960s, resistance to chloroquine and sulfadoxine-pyrimethamine originated, before it spread across Asia and to Africa, contributing to millions of deaths from malaria.
After previous reports of possible artemisinin resistance, two open label randomised trials of 40 patients each, one in Pailin, western Cambodia, and the other in Wang Pha, northwestern Thailand, compared the efficacies of two treatments for uncomplicated falciparum malaria—oral artesunate for seven days, and artesunate for three days followed by two doses of mefloquine.
The trials showed that in vivo susceptibility to artesunate is reduced in Plasmodium falciparum found in Cambodia compared with parasites from Thailand. The median parasite clearance time