Efficacy and Safety Study of Tafenoquine (TQ) Co-administered With Dihydroartemisinin-piperaquine (DHA-PQP) for the Radical Cure of Plasmodium Vivax (P. Vivax) Malaria

This intervention is provided as tablet containing 150 mg of tafenoquine. Two tablets of this formulation will be administered orally with water as a single dose after a meal. Dose will be taken at least 3 hours after DHA-PQP.

This intervention contains tafenoquine matched-placebo. Two tablets of this formulation will be administered orally with water as a single dose after a meal. Dose will be taken at least 3 hours after DHA-PQP.

This intervention is provided as over-encapsulated tablet containing 15 mg of primaquine. One capsule of this formulation will be administered orally with water as a single dose after a meal for 14 days. Dose will be taken at least 3 hours after DHA-PQP (Days 1, 2 and 3).

This intervention contains primaquine matched-placebo. One capsule of this formulation will be administered orally with water as a single dose after a meal for 14 days. Dose will be taken at least 3 hours after DHA-PQP (Days 1, 2 and 3).

This formulation is provided as tablet containing 320 mg of piperaquine tetrasphosphate (as the tetrahydrate; PQP) and 40 mg dihydroartemisinin (DHA). This tablet will be administered orally as single dose for 3 days. For subjects weighing \<75 kg, 3 tablets will be administered per day. For subjects weighing \>=75 kg, 4 tablets will be administered per day. Dose will be taken at least 3 hours after last food intake. No food will be allowed for at least 3 hours after dosing.

Subjects with relapse during the 180 day follow up period will be given an ACT plus PQ 0.5 mg/kg for 14 days as rescue medication.

Subjects who do not relapse during the study will receive PQ 0.5mg/kg for 14 days at the end of the study.