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Recruiting Phase 3 NCT06666491

NCT06666491 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

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Clinical Trial Summary
NCT ID NCT06666491
Status Recruiting
Phase Phase 3
Sponsor GlaxoSmithKline
Condition Malaria, Vivax
Study Type INTERVENTIONAL
Enrollment 300 participants
Start Date 2024-11-13
Primary Completion 2026-05-25

Eligibility & Interventions

Sex All sexes
Min Age 2 Years
Max Age 64 Years
Study Type INTERVENTIONAL
Interventions
TafenoquinePrimaquineChloroquine

Eligibility Fast-Check

Enter your details for a quick preliminary check. This does not replace medical advice.

What to Expect as a Participant

You will actively receive the study intervention — which may be a drug, biologic, device, or procedure.

Phase 3 trials are large pivotal studies comparing the treatment to current standard of care or placebo. Your participation directly contributes to the evidence needed for regulatory approval.

This trial targets 300 participants in total. It began in 2024-11-13 with a primary completion date of 2026-05-25.

⚠ This information is for research awareness only. Always consult your physician before joining any clinical trial. Participation is voluntary and you may withdraw at any time.

Brief Summary

The aim of this study is to collect efficacy and safety data to support the registration of tafenoquine in India.

Eligibility Criteria

Inclusion Criteria: 1. Males and females \>=2 years of age and under (\<) 65 years of age, weighing \>10 kg. 2. The participant has a positive malarial smear for P. vivax with a parasite density of \>100/microliter and \<100,000/microliter. 3. The participant has a screening Hb value \>8 g/dL. 4. The participant has an axillary temperature of 37.5°C or history of fever 48 hours before recruitment. 5. The participant has a G6PD value (measured using the SD Biosensor STANDARDTM G6PD test) 6.1 units/gram (U/g) Hb for G6PD activity (6.1 U/g Hb cut-off is applicable for both males and females). 6. A female participant is eligible to participate if she is not pregnant or breastfeeding, and if one of the following conditions applies: * Is a woman of non-childbearing potential (WONCBP) as defined in * Is a Women of Childbearing Potential (WOCBP) and using a contraceptive method that is highly effective (with a failure rate of \<1% per year), with low user dependency, during the study intervention period and for at least 90 days after the last dose of study intervention. The investigator should evaluate the potential for contraceptive method failure (e.g., noncompliance, recently initiated) in relationship to the first dose of study intervention. The investigator is responsible for review of medical history, menstrual history, and recent sexual activity to decrease the risk for inclusion of a woman with an early undetected pregnancy. 7. A WOCBP must test negative on a highly sensitive pregnancy test (urine or serum as required by local regulations) before the first dose of study intervention. 8. The participant is willing and able to comply with the procedures described in the study protocol. The participant or parent/legal guardian, as applicable, has given written informed, dated consent; and the participant has given written assent, if applicable, to participate in the study. 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).

Contact & Investigator

Central Contact

US GSK Clinical Trials Call Center

✉ GSKClinicalSupportHD@gsk.com

📞 877-379-3718

Frequently Asked Questions

Who can join the NCT06666491 clinical trial?

This trial is open to participants of all sexes, aged 2 Years or older, up to 64 Years, studying Malaria, Vivax. Full inclusion and exclusion criteria are listed in the Eligibility Criteria section. Always confirm your eligibility with the research team before applying.

What phase is the NCT06666491 trial and what does that mean for participants?

Phase 3 trials are large-scale studies comparing the new treatment to existing standards of care or a placebo. They provide the evidence needed for regulatory approval. This trial targets 300 participants.

Is NCT06666491 currently recruiting?

Yes, NCT06666491 is actively recruiting participants. Contact the research team at GSKClinicalSupportHD@gsk.com for enrollment information.

Where is the NCT06666491 trial being conducted?

This trial is being conducted at Ahmedabad, India, Kolkata, India, Mumbai, India, Surat, India.

Who is sponsoring the NCT06666491 clinical trial?

NCT06666491 is sponsored by GlaxoSmithKline. The trial plans to enroll 300 participants.

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