title: Open-label crossover study of primaquine and dihydroartemisinin-piperaquine pharmacokinetics in healthy adult thai subjects.
abstract: Dihydroartemisinin-piperaquine is an artemisinin-based combination treatment (ACT) recommended by the WHO for uncomplicated Plasmodium falciparum malaria, and it is being used increasingly for resistant vivax malaria where combination with primaquine is required for radical cure. The WHO recently reinforced its recommendations to add a single dose of primaquine to ACTs to reduce P. falciparum transmission in low-transmission settings. The pharmacokinetics of primaquine and dihydroartemisinin-piperaquine were evaluated in 16 healthy Thai adult volunteers in a randomized crossover study. Volunteers were randomized to two groups of three sequential hospital admissions to receive 30 mg (base) primaquine, 3 tablets of dihydroartemisinin-piperaquine (120/960 mg), and the drugs together at the same doses. Blood sampling was performed over 3 days following primaquine and 36 days following dihydroartemisinin-piperaquine dosing. Pharmacokinetic assessment was done with a noncompartmental approach. The drugs were well tolerated. There were no statistically significant differences in dihydroartemisinin and piperaquine pharmacokinetics with or without primaquine. Dihydroartemisinin-piperaquine coadministration significantly increased plasma primaquine levels; geometric mean ratios (90% confidence interval [CI]) of primaquine combined versus primaquine alone for maximum concentration (Cmax), area under the concentration-time curve from 0 h to the end of the study (AUC0-last), and area under the concentration-time curve from 0 h to infinity (AUC0-∞) were 148% (117 to 187%), 129% (103 to 163%), and 128% (102 to 161%), respectively. This interaction is similar to that described recently with chloroquine and may result in an enhanced radical curative effect. (This study has been registered at ClinicalTrials.gov under registration no. NCT01525511.).
authors.affiliation: Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Borimas
authors.initials: B
authors.lastname: Hanboonkunupakarn
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: Elizabeth A
authors.initials: EA
authors.lastname: Ashley
authors.affiliation: Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Podjanee
authors.initials: P
authors.lastname: Jittamala
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: Joel
authors.identifier: http://orcid.org/0000-0003-4566-4030
authors.initials: J
authors.lastname: Tarning
authors.affiliation: Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Sasithon
authors.initials: S
authors.lastname: Pukrittayakamee
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Warunee
authors.initials: W
authors.lastname: Hanpithakpong
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Palang
authors.initials: P
authors.lastname: Chotsiri
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Thanaporn
authors.initials: T
authors.lastname: Wattanakul
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand.
authors.forename: Salwaluk
authors.initials: S
authors.lastname: Panapipat
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: Sue J
authors.initials: SJ
authors.lastname: Lee
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom.
authors.forename: Nicholas P J
authors.initials: NP
authors.lastname: Day
authors.affiliation: Mahidol Oxford Tropical Medicine Research Unit, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand Centre for Tropical Medicine, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom nickw@tropmedres.ac.
authors.forename: Nicholas J
authors.initials: NJ
authors.lastname: White
mesh_terms: D000284:Administration, Oral; D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D000962:Antimalarials / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D037621:Artemisinins / Q000097:blood / Q000493:pharmacokinetics*; D001219:Aspartate Aminotransferases / Q000097:blood; D001682:Biological Availability; D018592:Cross-Over Studies; D004334:Drug Administration Schedule; D004359:Drug Therapy, Combination; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011319:Primaquine / Q000097:blood / Q000493:pharmacokinetics*; D011804:Quinolines / Q000097:blood / Q000493:pharmacokinetics*; D013785:Thailand; D010879:Piperazines
chemical_list: D000410:Alanine Transaminase; D000962:Antimalarials; D037621:Artemisinins; D001219:Aspartate Aminotransferases; D011319:Primaquine; D011804:Quinolines; C039060:artenimol; C034759:piperaquine; D010879:Piperazines