THE ACTIVITY OF PS-15 IN COMBINATION WITH SULFAMETHOXAZOLE

PS-15 is a novel biguanide folate antagonist that is metabolized in vi vo to WR99210, a metabolite that is extremely active in vitro against multi-drug resistant strains of Plasnodium falciparum. When PS-15 was administered in combination with sulfamethoxazole to healthy Saimiri s ciureus monkeys, the serum antimalarial activity was considerably grea ter than that observed in monkeys that received PS-15 alone. Further s tudies should be carried out to determine the value of PS-15/sulfonami de combinations in the treatment of human malaria infections and in pr eventing the emergence of drug-resistant parasites.