Schizontocidal effects of oral artesunate on Plasmodium berghei in mice and P knowlesi in monkeys

AIM: To study the blood schizontocidal effect of oral artesunate on P bergh ei in mice and P knowlesi in monkey. METHODS: Effects of artesunate and chl oroquine were detected with "4-day test" and "28-day test" on P berghei in mice and "7-day test" on P knowlesi in Macaca mudatta. RESULTS: The suppres sive efficacy of oral artesunate was inferior to chloroquine on P berghei K -173 Strain but the time for 50 % and 90 % reduction and the time of cleara nce of parasitemia was 10 - 15 h shorter than that of chloroquine. Its cura tive effect on RC/K-173 line was markedly superior to that of chloroquine. Moreover, artesunate showed no cross-resistance with chloroquine, index of resistance I-90 was only 1.4. At 31.6, 10.0, and 3.16 mg . kg(-1), artesuna te and chloroquine oral administrations cured P knowlesi in all monkeys. Re crudescence did not occur in 105 d. CONCLUSION: The study of effects of ora l artesunate in P berghei/mice and P knowlesi/Macaca mulatta model provided a useful index for clinical trial.