Randomized dose-ranging study of the safety and efficacy of WR 238605 (Tafenoquine) in the prevention of relapse of Plasmodium vivax malaria in Thailand

• Main Authors: Douglas S. Walsh, Sornchai Looareesuwan, Polrat Wilairatana, D. Gray Heppner, Douglas B. Tang, Thomas G. Brewer, Watcharee Chokejindachai, Parnpen Viriyavejakul, Dennis E. Kyle, Wilbur K. Milhous, Brian G. Schuster, John Horton, David J. Braitman, Ralf P. Brueckner
• Other Authors: Mahidol University
• Format: Article
• Published: 2018
• Subjects: Immunology and Microbiology; Medicine
• Online Access: https://repository.li.mahidol.ac.th/handle/123456789/25422

WR 238605 is an 8-aminoquinoline developed for the radical cure of Plasmodium vivax. Forty-four P. vivax-infected patients were randomly assigned to 1 of 4 treatment regimens: 3 groups received a blood schizonticidal dose of chloroquine followed by WR 238605: group A (n = 15) received 300 mg daily for 7 days; group B (n = 11), 500 mg daily for 3 days, repeated 1 week after the initial dose; group C (n = 9), 1 dose of 500 mg. A fourth group (D; n = 9) received chloroquine only. Among patients who completed 2-6 months of follow-up (n = 23), there was 1 relapse in group B (day 120) and 1 in group C (day 112). Among patients treated with chloroquine only, there were 4 relapses (days 40, 43, 49, and 84). WR 238605 was safe, well tolerated, and effective in preventing P. vivax relapse.