The World Health Organization (WHO) recommends combination drug therapy, with formulations containing an artemisinin compound, for the first-line treatment of multi-drug resistant Plasmodium falciparum malaria.
Ronan Jambou, Eric Legrand, and colleagues from the Pasteur Institute Network tested blood samples from 530 patients from 3 countries (Cambodia, French Guiana, and Senegal), which have different patterns of artemisinin use. They measured the response to drugs in common use in each country. The investigators found that some samples from French Guiana and Senegal, where use of artemisinin is uncontrolled, were resistant to artemisinin. The samples from Cambodia, which has controlled use of arteminsinin, did not show this loss of sensitivity. The researchers also found that the loss of sensitivity was associated with mutations in the gene (SERCA-type Pftpase6) thought to be the target of artemisinin derivatives.
Dr Jambou concludes: "All resistant isolates came from areas with uncontrolled use of artemisinin derivatives. This rise in resistance indicates the need for increased vigilance and a coordinated rapid deployment of drug combinations."
In an accompanying Comment Patrick Duffy (Seattle Biomedical Research Institute, Washington, USA) and Carol Sibley (University of Washington, USA) state: "Jambou and colleagues' paper is a wake-up call; resistance to artemisinins may indeed be selected by uncontrolled use of artemisinins as monotherapy or in conjunction with ineffective partners."
Contact: Dr R Jambou, Unité d'immunologie, Institut Pasteur de Dakar, PO Box 220, Dakar, Senegal. T) +221 839 92 43 firstname.lastname@example.org
Comment: Dr Patrick E Duffy, Malaria Antigen Discovery Program, Seattle Biomedical Research Institute, 307 Westlake Avenue North, Suite 500, Seattle, WA 98109, USA. T) 206-256-7311, email@example.com