In Tanzania, hemolysis after a single dose of primaquine coadministered with an artemisinin is not restricted to glucose-6-phosphate dehydrogenase-deficient (G6PD A-) individuals

The current interest in malaria elimination has led to a renewed interest in drugs that can be used for mass administration to minimize malaria transmission. Primaquine (PQ) is the only generally available drug with a strong activity against mature P lasmodium falciparum gametocytes, the parasite stage responsible for transmission. Despite concerns about PQ-induced hemolysis in glucose-6-phosphate dehydrogenase (G6PD)-deficient individuals, a single dose of PQ may be safe and efficacious in clearing gametocytes that persist after conventional treatment. As part of a mass drug intervention, we determined the hemolytic effect of sulfadoxine-pyrimethamine (SP) plus artesunate (AS) plus a single dose of primaquine (PQ; 0.75 mg/kg of body weight) in children aged 1 to 12 years. Children were randomized to receive SP+AS+PQ or placebo; those with a hemoglobin (Hb) level below 8 g/dl were excluded from receiving PQ and received SP+AS. The Hb concentration was significantly reduced 7 days after SP+AS+PQ treatment but not after placebo or SP+AS treatment. This reduction in Hb was most pronounced in G6PD-deficient (G6PD A−) individuals (−2.5 g/dl; 95% confidence interval [95% CI], −1.2 to −3.8 g/dl) but was also observed in heterozygotes (G6PD A) (−1.6 g/dl; 95% CI, −0.9 to −2.2 g/dl) and individuals with the wild-type genotype (G6PD B) (−0.5 g/dl; 95% CI, −0.4 to −0.6 g/dl). Moderate anemia (Hb level of