Patients with G6PD deficiency who are treated with 8-aminoquinolines have a risk of severe hemolysis.17 G6PD testing is recommended before administration of the primaquine regimen used in this trial, and it will be required before administration of tafenoquine.35 The qualitative test evaluated here failed to identify 16 patients most at risk for hemolysis. This evidence concerns the gene G6PD and G6PD deficiency.