Preventative treatment with a monthly dose of a newer antimalarial drug can reduce the risk of malarial infection among young children, according to a study published in this week's PLOS Medicine. The study, conducted by Victor Bigira and colleagues at San Francisco General Hospital and the Makerere University College of Health Sciences in Kampala, Uganda, finds that treating young children with dihydroartemisinin-piperaquine (DP) decreased their risk of contracting malaria.
Preventative treatment of malaria is a useful strategy to protect young children in Africa, but it is unclear which drug and dosing strategy is most effective, especially with the rise of resistance to a class of drug known as antifolates, such as sulfadoxine-pyrimethamine (SP) and trimethoprim-sulfamethoxozole (TS). In this randomized controlled trial, the authors compared three treatment regimens, monthly SP, daily TS, monthly DP (a newer artemisinin-based combination therapy), and a no treatment control. The study enrolled 393 infants from Tororo, Uganda, and treated them from 6 to 24 months of age. The authors found that the incidence of malaria among the children treated with DP was lower than those with no treatment, 3.02 vs 6.95 episodes per person year (a protective efficacy of 58%). The protective efficacies of SP and TS were lower (7% and 28%) than DP.
There was no significant increase in adverse events with any of the treatments over the control group, nor was there any difference in malaria incidence between groups during the one year period after the study treatment was stopped, suggesting that monthly administration of DP is a safe and effective treatment for reducing malaria among infants in regions with year-round transmission and high resistance to antifolates.
The authors say: "The excellent efficacy of DP for the treatment of malaria in multiple countries and for chemoprevention in our high transmission area suggest that this regimen will offer benefit in many regions in need of improved control measures."
They continue: "... future studies are needed to evaluate the preventive efficacy of DP in other areas, maintain surveillance for potential selection of drug-resistant parasites, and evaluate the role of chemoprevention in the context of other available malaria control interventions such as the scale up of [insecticide treated nets] and use of indoor residual spraying of insecticides."