 Nested sub-study 2, is a comparative bioavailability study to compare lumefantrine bioavailability after the first oral dose of AL among pediatric patients receiving standard care. Forty eight out of the 70 under five year old children with uncomplicated malaria will be randomized to receive AL with either milk n24 or local maize porridge plus oil n24. Venous plasma concentrations 1 ml, whole blood will be obtained up to 8 hours at 0, 1, 1.5, 2, 3, 4, 6, 8 after the first using an intensive pharmacokinetic sampling design. Thereafter 1 to 8 sparse venous blood samples will be obtained during a 28 day follow up period to contribute to the PPK study pool. Primary Pharmacokinetic endpoints and outcomes will be exposure parameters after first dose, up to 8 h. Peak concentrations Cmax and early exposure AUC0-8h will be used for relative bioavailability evaluations using confidence interval approach for average bioequivalence. Secondary end points will be day 28 in follow up with lumefantrine PK exposure AUC0-28d and AUC0- and day 28 treatment outcomes as secondary outcomes. Correlation of overall exposure AUC0-28d and AUC0- to clinical and parasitological response to AL treatment will be explored. 