In vitro interactions between antiretroviral protease inhibitors and artemisinin endoperoxides against Plasmodium falciparum.

Antiretroviral protease inhibitors (APIs), which are effective at controlling the effects of human immunodeficiency virus (HIV) in patients, have also proven efficacious in inhibiting Plasmodium falciparum growth in vitro. Use of artemisinin-based combination therapies is being encouraged to reduce malaria mortality in areas of P. falciparum resistance to conventional antimalarial drugs. The aim of this study was to investigate drug interactions between HIV protease inhibitors and artemisinin drugs against malaria. In vitro cultures of P. falciparum provide a screen system for identifying and evaluating drug combinations. The derived isobolograms provide clear evidence of antagonistic interactions between artemisinin endoperoxides and several different APIs.