Spirogermanium: a new drug with antimalarial activity against chloroquine-resistant Plasmodium falciparum.

Spirogermanium, a new investigational drug of novel structure currently under clinical studies in various neoplastic diseases, has revealed significant in vitro activity against chloroquine-resistant (FCB, FTA, FVO) and sensitive (FSL, FUI, FH) strains of Plasmodium falciparum. Inhibition of the growth and maturation of parasites after 36-h exposures to Spirogermanium started at concentrations ranging from 2.48 to 9.9 nM/ml. These concentrations appear to be within the range of Spirogermanium plasma levels reported in clinical studies with this drug. Since its clinical toxicities are unusually low in comparison with other anticancer drugs, our results on its in vitro activity against Plasmodium falciparum indicate Spirogermanium is an antimalarial drug of entirely novel structure, active in resistant strains.