A Phase 2 interventional study of Chloroquine and Primaquine in Vivax Malaria and G6PD Deficiency, sponsored by Fundação de Medicina Tropical Dr. Heitor Vieira Dourado. Completed at 2 sites in Brazil. Open to participants aged 6 Months and older. Per ClinicalTrials.gov, last updated 2025-02-20.
Sponsored by Fundação de Medicina Tropical Dr. Heitor Vieira Dourado · Phase 2, Interventional, and Treatment
A clinical study to assess the safety and efficacy of alternative regimens of primaquine for radical cure of vivax malaria in glucose 6-phosphate dehydrogenase (G6PD) deficient. G6PD deficient patients with P. vivax monoinfection will be treated with either weekly or delayed one-week course of primaquine, and the currently recommended by national guideline, 12-week chloroquine regimen to compare treatment safety among groups. All groups will be actively monitored for hemolysis during treatment and will have six-month follow-up period to assess treatment efficacy.
This is an open-label, randomized, phase II, clinical trial of safety and efficacy. Patients will be screened for eligibility and treated at the Fundação de Medicina Tropical Dr Heitor Vieira Dourado in Manaus and the Centro de Pesquisa em Medicina Tropical (Cepem) in Porto Velho, Brazil. A total of 104 vivax malaria patients will be recruited into the study, 52 G6PD deficient (Arm 1) and 52 G6PD normal (Arm 2). Patients with spectrophotometrically-confirmed G6PD deficiency (10-60% of adjusted mean male activity) will be divided into three subgroups of 10 patient each. All arms will receive standard 3-day chloroquine course. Additionally, Arm 1a will receive a delayed course of primaquine for 7 days, starting only at the fifth-day post-chloroquine initiation [ARM HALTED DUE TO SAFETY CONCERNS]. Arm 1b will receive weekly primaquine, once a week, for 8 weeks. Arm 1c will receive prophylactic 12-week course of chloroquine, as recommended by national guidelines for such patients (control group in terms of safety). Arm 2, the control group of efficacy, will receive standard regimen, comprised of 3-day chloroquine plus concomitant 7-day primaquine. All patients will receive directly observed therapy (DOT) and will be closely monitored for clinical parameters and laboratory markers of hemolysis including hemoglobin, methemoglobin, lactate dehydrogenase, haptoglobin, reticulocytes, indirect bilirubin, aspartate aminotransferase, and urinalysis. All groups will be followed for 6 months after treatment to assess relapse rate. Primary endpoint is the tolerability of the regimens defined by hemoglobin fall. Secondary endpoints include treatment failure (relapse during follow-up), frequency of adverse effects, and rate of hemoglobin fall during treatment.
1,299 studies on the registry are indexed under Malaria; 86 are open to participants now.
This study's enrollment of 106 is below the median of 220 across 1,027 interventional studies indexed under Malaria.
Browse Malaria studies →Fundação de Medicina Tropical Dr. Heitor Vieira Dourado is the lead sponsor of 11 studies on the registry; none are open to participants now.
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Exclusion Criteria:
\[ARM HALTED PREMATURELY DUE TO SAFETY CONCERNS\]
Drug: Chloroquine · Drug: Primaquine
26 G6PD deficient patients. Directly observed therapy.
Drug: Chloroquine · Drug: Primaquine
26 G6PD deficient patients. Control group in terms of safety. Directly observed therapy.
Drug: Chloroquine
52 G6PD normal patients. Control group in terms of efficacy. Directly observed therapy.
Drug: Chloroquine · Drug: Primaquine
Standard chloroquine (three days)
Daily Primaquine (0.5 mg of base/kg/day for seven days) starting only at the fifth day post chloroquine initiation.
Weekly primaquine (0.75 mg of base/kg/week for eight weeks) starting with first dose of chloroquine.
Weekly, once a week chloroquine (5 mg of base/kg/week for twelve weeks)
Standard primaquine (0.5mg of base/kg/day for seven days) concomitant with chloroquine.
Absolute or relative change in hemoglobin < 3g/dL or 30% from baseline
Hemoglobin reduction from baseline after exposure to primaquine for P. vivax treatment
Time frame: From date of randomization until the date of last dose, assessed up to 12 weeks.
Regimen efficacy
Relapse rate over follow-up period after treatment
Time frame: 6 months post treatment
Adverse effects
Presence of adverse reactions as a result of intervention, measured by clinical and laboratory tests
Time frame: From date of randomization until the date of first documented event, assessed up to 12 weeks.
Change in hemoglobin values over treatment
Absolute variation of hemoglobin levels before and during intervention.
Time frame: through study completion: before intervention and up to 12 weeks during intervention.
Plan to share: Undecided
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This study is completed, as verified in Feb 2025. You cannot join it, but the record below documents what was studied.
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Fundação de Medicina Tropical Dr. Heitor Vieira Dourado