Gabon

A thermostable suppository of artesunate (artesunic acid) has been developed. In Gabon, 12 children with Plasmodium falciparum malaria received two administrations of this suppository in a 4-hr interval. Parasitemia and fever were then measured and the plasma levels of artesunate and its active metabolite, dihydroartemisinin, were determined by means of a reversed phase high-pressure liquid chromatography method using reductive electrochemical detection.

The sensitivity of Plasmodium falciparum to chloroquine, mefloquine, quinine, quinidine, halofantrine, artemisinin, and sulfadoxine/pyrimethamine was investigated in Lambarene, Gabon in 1994. The development of in vitro susceptibility has been traced from 1983 or 1992 to 1994 for chloroquine, mefloquine, halofantrine, and quinine. Standard in vitro microtests according to World Health Organization methodology were performed.

Recently, artemisinin derivatives have been shown to be efficacious in chemoprophylaxis of and chemotherapy for Schistosoma japonicum and S. mansoni infections. Therefore, a double-blind, randomized, placebo-controlled study was carried out to investigate the efficacy and tolerability of artesunate plus placebo and the combination of artesunate and praziquantel in the treatment of S. haematobium infections in Gabon.

Artesunate (ARS) is a water-soluble artemisinin derivative that is a potential alternative to quinine for the treatment of severe childhood malaria. We studied the pharmacokinetics and bioavailability of ARS given by the intramuscular (i.m.) route in an open crossover study design. Fourteen children were randomized to receive intravenous (i.v.) ARS in a loading dose (2.4 mg/kg of body weight) followed 12 h later by an i.m. dose (1.2 mg/kg) (group I), and 14 children were randomized to receive i.m. ARS (2.4 mg/kg) followed by an i.v. dose of ARS (1.2 mg/kg) (group II).

Artesunate is one of the most important antimalarial agents available, since it is effective against parasites that have developed resistance to conventional antimalarials in sub-Saharan Africa. Antimalarial combination chemotherapies with artesunate (4 mg/kg of body weight once daily for 3 days) as one partner have been proposed.

BACKGROUND: Artemisinin-based drug combinations are the mainstay in the fight against drug-resistant malaria in Africa. Currently available antimalarial drug combinations that include artemisinins are pharmacokinetically unmatched and are therefore potentially increasing the risk of selection of resistant mutants in areas in which the rate of transmission of malaria is high. We tested the potential value of artemisinin-based combination therapy with a short elimination half-life for the treatment of uncomplicated Plasmodium falciparum malaria in sub-Saharan Africa.

Despite different recommendations from WHO and national authorities, artesunate monotherapy is increasingly used for treating African children with malaria. A 5-day course of oral artesunate (first day: 4 mg/kg body weight, observed intake; and 2 mg/kg body weight on the following days with nonobserved drug intake) yielded a PCR-corrected Day 28 cure rate of 90% (45 of 50 patients; CI 78-97%) in Gabonese children aged between 2 and 18 months. Artesunate was well tolerated, and no severe adverse events were reported.

BACKGROUND: It has been shown that Plasmodium falciparum submicroscopic infections (SMI) can contribute to malaria-associated anemia as well as to cerebral malaria. Polymerase chain reaction (PCR) assays are usually used as an alternative to microscopy in detecting subpatently infected individuals. OBJECTIVES: The main objective of this study was to investigate the occurrence of SMI before and after a suppressive antimalarial treatment in the population of the village of Dienga in Gabon. METHODS: Nested PCR was used to detect SMI and to determine genotypes.

BACKGROUND: Artesunate-amodiaquine combination for the treatment of childhood malaria is one of the artemisinin combination therapies (ACTs) recommended by National authorities in many African countries today. Effectiveness data on this combination in young children is scarce. METHODS: The effectiveness of three daily doses of artesunate plus amodiaquine combination given unsupervised (n = 32), compared with the efficacy when given under full supervision (n = 29) to children with falciparum malaria were assessed in an unrandomized study.

OBJECTIVES: Paediatric drug formulations of artemisinin combination therapies and pharmacokinetic data supporting their use in African children are urgently needed for the effective treatment of young children suffering from falciparum malaria in sub-Saharan Africa. PATIENTS AND METHODS: In this study, the pharmacokinetic characteristics of a novel paediatric granule formulation of artesunate-mefloquine therapy were evaluated in comparison to the standard tablet formulation in the treatment of uncomplicated malaria in paediatric patients.