 In the current study the investigators aim to assess safety of PQ, in particular the risk of acute haemolysis, when given together with dihydroartemisinin-piperaquine DHAP in G6PD deficient individuals. Forty male participants with haemoglobin levels 11gdL, reduced G6PD enzyme function, and aged 10years will be sequentially enrolled into two dosing cohorts consisting of 20 individuals and doses of 0.25 and 0.4 mgkg PQ in combination with a full three-day course of DHAP. Participants will first be assigned to the lowest open cohort; enrolment in the next cohort is initiated after tolerability and short-term safety is demonstrated at the preceding lower dose. Furthermore, the investigators will include 3 control groups into the first cohort: i 10 male participants aged 10years with normal haemoglobin levels 11gdL and a reduced G6PD enzyme function will receive DHAP only, ii 10 male participants with normal haemoglobin levels 11gdL and normal G6PD enzyme function will receive 0.25 mgkg PQ in combination with a full three-day course of DHAP, and iii 10 male participants with normal haemoglobin levels 11gdL and normal G6PD enzyme function will receive 0.4 mgkg PQ with DHAP. 