Population pharmacokinetic and pharmacodynamic modelling of artemisinin and mefloquine enantiomers in patients with falciparum malaria.
2002 (English)In: European Journal of Clinical Pharmacology, ISSN 0031-6970, E-ISSN 1432-1041, Vol. 58, no 5, 339-351 p.Article in journal (Refereed) Published
Objectives: The aims of this study were to investigate whether artemisinin influences the pharmacokinetics of mefloquine enantiomers or vice versa and to model the antiparasitic effect of these drugs alone and in combination in Plasmodium falciparum malaria patients. Methods: Forty-two male and female patients., were randomised to treatment with either oral artemisinin 500 mg daily for 3 days followed by oral mefloquine 750 mg on day 4, oral artemisinin 5,00 mg daily for 3 days plus oral mefloquine 750 mg on day 1 or a single 750-mg oral dose of mefloquine. The data was modelled using NONMEM. Results: All patients were successfully treated regardless of treatment. The fastest parasite clearance rates were observed in patients receiving artemisinin together with mefloquine on the first day of treatment. Apharmacodynamic model based on the life cycle of P. falciparum successfully described the efficacy ofartemisinin, me floquine and the combination. The time artemisinin concentration stays above a minimum inhibitory concentration was estimated to 2.97 h (relative standard error 4.7 h). The two mefloquineenantiomers exhibited different pharmacokinetics, with an oral clearance of 3.51 (7.9) l/h and 0.602 (6.9) l/h for RS-mefloquine and SRL mefloquine, respectively. In patients receiving only artemisinin the first 3 days,artemisinin oral clearance was 6.9-fold higher the last day of treatment compared with the first day. There was no difference in the pharmacokinetics of mefloquine enantiomers when mefloquine was given alone, incombination with artemisinin or after a 3-day regimen of artemisinin. There was a tendency towards, although non-significant, higher artemisinin concentrations when artemisinin was given together with mefloquinecompared with when given alone. Conclusions: No significant pharmacokinetic interactions were observed after co-administration of artemisininand mefloquine. The P. falciparum malaria pharmacodynamic model successfully described the antimalarial effect of artemisinin, mefloquine and a combination of the two drugs.
Place, publisher, year, edition, pages
2002. Vol. 58, no 5, 339-351 p.
Adolescent, Adult, Antimalarials/chemistry/pharmacokinetics/*pharmacology/therapeutic use, Artemisinins/chemistry/pharmacokinetics/*pharmacology/therapeutic use, Drug Interactions, Drug Therapy; Combination, Humans, Malaria; Falciparum/drug therapy/*metabolism, Mefloquine/chemistry/pharmacokinetics/*pharmacology/therapeutic use, Middle Aged, Models; Biological, Research Support; Non-U.S. Gov't, Sesquiterpenes/chemistry/pharmacokinetics/*pharmacology/therapeutic use, Stereoisomerism, Structure-Activity Relationship
Medical and Health Sciences
IdentifiersURN: urn:nbn:se:uu:diva-72669DOI: 10.1007/s00228-002-0485-yISI: 000177938300007PubMedID: 12185558OAI: oai:DiVA.org:uu-72669DiVA: diva2:100580