The purpose of this study is to evaluate the tolerability and safety of increasing doses of primaquine in combination with artemether-lumefantrine in G6PD deficient males with an asymptomatic P. falciparum malaria infection.

Inclusion Criteria:

1. Male gender
2. Age ≥18 years and ≤45 years
3. BMI ≥16
4. P. falciparum parasitaemia at any density
5. G6PD deficiency by Beutler Fluorescent Spot test for intervention groups and control group receiving AL only (N=50)
6. G6PD normal activity by Beutler Fluorescent Spot test for control groups (N=20)
7. Informed consent by participant

Exclusion Criteria:

1. Enrolled in another clinical trial
2. Fever >37.5°C (tympanic) or history of fever in the last 24 hours
3. Evidence of severe illness / danger signs or active infection other than malaria
4. Known allergy to study medications
5. Hb <11 g/dL
6. Antimalarials taken within the last 2 weeks
7. PQ taken within the last 4 weeks and blood transfusion within the last 90 days
8. Non-falciparum malaria co-infection
9. Current use of tuberculosis or anti-retroviral medication, sulphonamides, dapsone, nitrofurantoin, , nalidixic acid, ciprofloxacin, , methylene blue, toluidine blue phenazopyridine and co-trimoxazole.
10. History of severe chronic illness