 Malaria and HIV are among the two most important global health problems of our time. Malaria accounts for up to 3 million deaths each year, of which 90 occur in Africa where malaria is the leading cause of mortality in young children. Artemisinin-based combination therapy ACT are the mainstay of antimalarial therapy throughout much of the world, yet pediatric pharmacokinetic data on the most widely adopted ACT regimen, artemetherlumefantrine AL are lacking. Of equal importance is the assessment of key drug-drug interactions in HIV co-infected children as ARVs are known to affect the metabolic enzyme activity responsible for ACT elimination. This study proposes to investigate the drug-drug interaction between the antimalarial artemetherlumefantrine and nevirapine based antiretroviral ARV treatment for HIV in children co-infected in resource limited settings. 