An Interventional Study to Compare the Efficacy and Safety of Tafenoquine (TQ) and Primaquine (PQ) When Either Are Taken Together With Chloroquine (CQ) for the Treatment of P. Vivax Malaria in Indian Participants Aged 2 Years and Older

Exclusion Criteria

• •1. The participant has severe P. vivax malaria as defined by WHO criteria \[WHO, 2023\].
• •2. The participant has a mixed malaria infection (identified by a malarial smear).
• •3. The participant has a condition that may affect absorption of study medication, such as severe vomiting (no food or inability to take food during the previous 8 hours).
• •4. The participant has a history of porphyria, psoriasis, or epilepsy.
• •5. The participant has a history of allergy, intolerance to or a known contraindication to the use of mefloquine (or other aryl amino alcohol drugs), chloroquine, tafenoquine, primaquine, any other 4- or 8-AQ or any of their respective excipients.
• •6. The participant has received treatment with any investigational drug within 30 days of study entry, or within 5 half-lives, whichever is longer.
• •7. The participant has previously enrolled in this study.
• •8. The participant has a recent history of illicit drug abuse or heavy alcohol intake that in the opinion of the investigator could compromise full participation in the study or adherence to study procedures.
• •9. Participants with a current or past history of serious psychiatric disorders.
• •10. The participant has a clinically significant concurrent illness (e.g., pneumonia, tuberculosis, meningitis, septicemia, dengue, coagulopathy, severe hemorrhage, or febrile convulsions prior to consent) or a pre-existing condition (e.g., renal disease, malignancy, or severe malnutrition according to WHO child growth standards) or systemic disease predisposing patients to suffer from granulocytopenia, such as rheumatoid arthritis and lupus erythematosus or severe ocular disease.
• •11. The participant is known to be HIV-infected and/or is currently on antiretroviral therapy.
• •12. The participant is regularly using drugs with hemolytic potential.
• •13. The participant has a QT corrected by Fridericia's formula (QTcF) \>450 msec, evidence of bradycardia (\<50 beats per min) or ventricular arrhythmias on the screening ECG, a history of cardiac disease (e.g., myocardial infarction, congenital heart disease, or arrhythmia), hypokalemia (\<2.9 millimoles per liter \[mmol/L\]) or hyperkalemia (\>=6.0 mmol/L) at Screening.
• •14. The participant has taken drugs with antimalarial activity (e.g., artemisinin-based combination therapies, mefloquine, primaquine, chloroquine, tafenoquine or any other 4-AQ) within 30 days prior to study entry.
• •15. The participant has taken or will likely require during the study the use of:
• •1. Histamine-2 blockers (restricted to first 3 days whilst receiving CQ)
• •2. Antacids (restricted to first 3 days whilst receiving CQ)
• •3. Drugs of the biguanide class (i.e., phenformin, metformin, buformin)
• •4. Anti-arrhythmic agents (i.e., dofetilide, procainamide, pilsicainide)
• •5. Medications that prolong the QTc interval
• •16. The participant has liver transaminases (ALT/AST) \>2 times the upper limit of normal (ULN).