A Randomized Comparison of Chloroquine Versus Dihydroartemisinin–Piperaquine for the Treatment of Plasmodium vivax Infection in Vietnam
Thuan PD., Ca NTN., Van Toi P., Nhien NTT., Thanh NV., Anh ND., Phu NH., Thai CQ., Thai LH., Hoa NT., Dong LT., Loi MA., Son DH., Khanh TTN., Dolecek C., Nhan HT., Wolbers M., Thwaites G., Farrar J., White NJ., Hien TT.
A total of 128 Vietnamese patients with symptomatic Plasmodium vivax mono-infections were enrolled in a prospective, open-label, randomized trial to receive either chloroquine or dihydroartemisinin–piperaquine (DHA-PPQ). The proportions of patients with adequate clinical and parasitological responses were 47% in the chloroquine arm (31 of 65 patients) and 66% in the DHA-PPQ arm (42 of 63 patients) in the Kaplan–Meier intention-to-treat analysis (absolute difference 19%, 95% confidence interval = 0–37%), thus establishing non-inferiority of DHA-PPQ. Fever clearance time (median 24 versus 12 hours, P = 0.02), parasite clearance time (median 36 versus 18 hours, P < 0.001), and parasite clearance half-life (mean 3.98 versus 1.80 hours, P < 0.001) were all significantly shorter in the DHA-PPQ arm. All cases of recurrent parasitemia in the chloroquine arm occurred from day 33 onward, with corresponding whole blood chloroquine concentration lower than 100 ng/mL in all patients. Chloroquine thus remains efficacious for the treatment of P. vivax malaria in southern Vietnam, but DHA-PPQ provides more rapid symptomatic and parasitological recovery.