In 75 Zambian and Thai subjects with mild to moderate infection with Plasmodium falciparum or Plasmodium vivax, 3-day infusions of desferrioxamine B (100 mg/kg/day) as a single agent enhanced the clearance of asexual peripheral blood parasites, but recrudescence occurred in most subjects. In 83 Zambian children with cerebral malaria who were randomized to receive desferrioxamine B or placebo in addition to standard quinine-based therapy as part of a prospective double-blind trial, both parasite clearance and recovery from coma were faster with administration of the iron chelator. Retrospective studies in the children with cerebral malaria raised the possibility that, in addition to withholding iron from the parasite, desferrioxamine B may have enhanced the T helper 1 immune response and protected against iron-mediated peroxidant cerebral tissue damage.