Moving towards high-dose primaquine or single-dose tafenoquine for Plasmodium vivax treatment in Cambodia: a meeting report from dissemination of results of the EFFORT trial to stakeholders
Cambodia has targeted malaria elimination by 2025. As the malaria burden has decreased in Cambodia, transmission has become more focal, and Plasmodium vivax has become the predominant species. The recurrent nature of P. vivax, due to its dormant liver stages causing relapses, is the main obstacle to malaria elimination in Cambodia. In 2021, Cambodia's National Center for Parasitology, Entomology and Malaria Control (CNM) rolled out low-dose 14-day primaquine (total dose 3.5 mg/kg) supported by point-of-care quantitative testing for glucose-6-phosphate dehydrogenase deficiency. However, this treatment is limited by poor adherence to its prolonged duration and suboptimal efficacy of the low total dose. The EFFORT clinical trial was conducted in four malaria-endemic countries, including Cambodia, to assess the safety and effectiveness of a 7-day unsupervised high-dose course of primaquine (7 mg/kg total dose) and single dose tafenoquine (300 mg) compared to 14-day unsupervised low-dose primaquine for the treatment of patients presenting with P. vivax malaria. In addition, data were collected on the feasibility and cost-effectiveness of these treatment options. CNM organized the national dissemination of the EFFORT study results on March 27, 2025, to inform key stakeholders and discuss the implications of the study findings for policy and practice in Cambodia.
Authors
- Hok Kry
- Voeurng Bunreth
- Sovann Peng
- Sarah A. Cassidy-Seyoum (ORCID: https://orcid.org/0000-0003-0802-347X)
- Thoang Sokha
- Yok Sovann
- Ung Soviet
- Koung Lo
- Angela Devine (ORCID: https://orcid.org/0000-0002-3321-8706)
- Bipin Adhikari (ORCID: https://orcid.org/0000-0001-8981-3910)
- Sarith Oum
- Hannah Brindle (ORCID: https://orcid.org/0000-0003-1684-5801)
- Caroline A. Lynch (ORCID: https://orcid.org/0000-0003-0072-0473)
- Prak Vonn
- Ke Kimmen
- Khoy Dy
- Aaryan Dahal (ORCID: https://orcid.org/0009-0004-0992-0601)
- Kamala Thriemer
- Pascal Ringwald
- Jayme Hughes
- Rupam Tripura
- Nead Phoumen
- Sam Vantha
- Leng Naren
- Ric N. Price
- Huot Khlok
- Pov Rathana
- Yang Hu
- Chhun Bunmeng
- Pen Kim Heng
- Rin Ravuth
- Socheat Heoy
- Sodavuth Preap
- Siv Samol
- Lorenz von Seidlein
- Keo Vannak
- Tov Moeng
- Sin Srey
- Oum Sovanarath
- Farooq Sabawoon
- Yim Heng
- Touch Phalla
- Iv Makara
- Ly Kanha
- Hor Mengkea
- Ma Sokhann
- Nuon Sokunthea
- Prum Mardi
- But Engrkruy
- Khourn Pong
- Im Chanry
- Lek Dysoley
- Ros Channavuth
Institutions
- World Health Organization - Pakistan (PK)
- Catholic Relief Services (US)
- The University of Melbourne (AU)
- Ministry of Health (KH)
- Mahidol University (TH)
- Cambodia National Malaria Center (KH)
- Charles Darwin University (AU)
- University of Cambodia (KH)
- University of Oxford (GB)
- Menzies School of Health Research (AU)
- Chea Sim University of Kamchaymear (KH)
- National Institute of Public Health (KH)
- National Defense University (KH)
- Cambodia-Oxford Medical Research Unit (KH)
- Chab Dai (KH)
- Documentation Center of Cambodia (KH)
- Mahidol Oxford Tropical Medicine Research Unit (TH)
- National Meanchey University (KH)
- Sihanouk Hospital Center of HOPE (KH)
- Medicines for Malaria Venture (CH)
- Royal University of Phnom Penh (KH)
Publication Details
- Journal
- Malaria Journal
- Published
- 2026-01-03
- DOI
- https://doi.org/10.1186/s12936-025-05691-1
- Primary Topic
- Malaria Research and Control
- Type
- article
- Field-Weighted Citation Impact
- 0.00
Funders
- Bill and Melinda Gates Foundation
- Medical Research Council
- National Health and Medical Research Council