Proteases of malaria parasites: new targets for chemotherapy.

The increasing resistance of malaria parasites to antimalarial drugs is a major contributor to the reemergence of the disease as a major public health problem and its spread in new locations and populations. Among potential targets for new modes of chemotherapy are malarial proteases, which appear to mediate processes within the erythrocytic malarial life cycle, including the rupture and invasion of infected erythrocytes and the degradation of hemoglobin by trophozoites. Cysteine and aspartic protease inhibitors are now under study as potential antimalarials. Lead compounds have blocked in vitro parasite development at nanomolar concentrations and cured malaria-infected mice. This review discusses available antimalarial agents and summarizes experimental results that support development of protease inhibitors as antimalarial drugs.