Efficacy and effectiveness of five day treatment of uncomplicated falciparum with artemisinin or artesunate in Vietnam

A study on efficacy and effectiveness of artemisinin (total dose of 60 mg/kg) and artesunate (total dose of 12 mg/kg over five days) in treatment of uncomplicated malaria was conducted in highly malaria transmitted areas in Vietnam. 126 uncomplicated malaria cases finished 14 day follow-up. 100% cure rate achieved at day 14 in patients of the efficacy groups received either artemisinin or artesunate, while it was 83% and 93% in patients treated respectively with artemisinin and artesunate of the effectiveness groups. Compliance of the treatment regimens was discussed.

The pharmacokinetics of a single dose of artemisinin in patients with uncomplicated falciparum malaria

The pharmacokinetics of artemisinin was studied in 11 Vietnamese patients with uncomplicated falciparum malaria after a single 500 mg oral dose. Curative treatment with mefloquine (15 mg/kg) was provided 24 hr after the artemisinin dose. Artemisinin concentrations were measured by high-performance liquid chromatography with electrochemical detection. The following pharmacokinetic results were found (all mean +/- SD); calculated volume of distribution/bioavailability = 22.8 +/- 16.6 L.kg-1, mean absorption time = 1.16 +/- 0.92 hr, calculated maximum concentration = 364 +/- 250 micrograms.L-1 occurring at 2.88 +/- 1.71 hr after drug intake, and an elimination half-life of 2.72 +/- 1.76 hr. Bioavailability was low. These results do not differ from results in healthy subjects. Parasites disappeared rapidly, with a mean parasite clearance time of 36 hr. No relationship was found between pharmacokinetics and the parasite elimination rate. Tolerance to the single dose of artemisinin was good. No adverse effects were detected. In conclusion, pharmacokinetics of a single dose of artemisinin for uncomplicated falciparum malaria is not different from findings in healthy subjects. A single dose of 500 mg of artemisinin is effective in reducing parasitemia in nonsevere lalciparum malaria and is well-tolerated.