ArticleMalaria journal2021
Increased primaquine total dose prevents Plasmodium vivax relapses in patients with impaired CYP2D6 activity: report of three cases.
Article in Malaria journal, 2021. The graph could read no effect estimate from its abstract, so it casts no vote on the map. Cited by 12 papers, 1 of them a synthesis that pooled it.
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Who cites it
12 citing papers in PubMed, 1 synthesis or guideline pooled it, 15 citations in OpenAlex.
- Effect of primaquine dose on the risk of recurrence in patients with uncomplicated Plasmodium vivax: a systematic review and individual patient data meta-analysis.The Lancet. Infectious diseases · 2024Pooled it
- CYP3A and CYP2D6 variability in antimalarial pharmacokinetics and pharmacogenetics across populations: a narrative review.Malaria journal · 2026Review
- Efficacy of primaquine-chloroquine combination onParasite epidemiology and control · 2026Article
- Reduced cytochrome P-450 (CYP) 2D6 activity and Plasmodium vivax malaria risk in Amazonians: A retrospective, population-based cohort study.PLoS neglected tropical diseases · 2026Article
- Efficacy of Primaquine for the Radical Cure of Plasmodium vivax Malaria in Northeast Myanmar and the Impact of Cytochrome P450 2D6 Genotypes.Clinical infectious diseases : an official publication of the Infectious Diseases Society of America · 2025Article
- Enhanced data quality to improve malaria surveillance in Papua, Indonesia.Malaria journal · 2025Article
- Towards malaria elimination: a case-control study to assess associated factors to malaria relapses in the extra-Amazon Region of Brazil from 2008 to 2019.Malaria journal · 2024Article
- Article
- RelapsingMalariaWorld journal · 2024Article
- Prevalence of G6PD deficiency and submicroscopic malaria parasites carriage in malaria hotspot area in Northwest, Tanzania.Malaria journal · 2023Article
- Magic bullets, magic shields, and antimicrobials in between.Pharmaceutical science advances · 2023Review
- Plasmodium vivax: the potential obstacles it presents to malaria elimination and eradication.Tropical diseases, travel medicine and vaccines · 2022Review
Corrections and comments
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Authors and funding
13 authors at 4 institutions in 1 country.
Funding
Abstract
backgroundThe relapsing nature of Plasmodium vivax infection is a major barrier to its control and elimination. Factors such as adequate dosing, adherence, drug quality, and pharmacogenetics can impact the effectiveness of radical cure of P. vivax and need to be adequately evaluated. CYP2D6 pathway mediates the activation of primaquine (primaquine) into an active metabolite(s) in hepatocytes, and impaired activity has been linked to a higher risk of relapse. CASES PRESENTATION: Three patients diagnosed with P. vivax malaria presented repeated relapses after being initially treated with chloroquine (25 mg/kg) and primaquine (3.5 mg/kg in 14 days) at a non-endemic travel clinic. Recurring episodes were subsequently treated with a higher dose of primaquine (7 mg/kg in 14 days), which prevented further relapses in two patients. However, one patient still presented two episodes after a higher primaquine dose and was prescribed 300 mg of chloroquine weekly to prevent further episodes. Impaired CYP2D6 function was observed in all of them.
conclusionLack of response to primaquine was associated with impaired CYP2D6 activity in three patients presenting multiple relapses followed in a non-endemic setting. Higher primaquine dosage was safe and effectively prevented relapses in two patients and should be further investigated as an option in Latin America. It is crucial to investigate the factors associated with unsuccessful radical cures and alternative therapeutic options.
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