EFFICACY AND SAFETY OF ATOVAQUONE PROGUANIL AS SUPPRESSIVE PROPHYLAXIS FOR PLASMODIUM-FALCIPARUM MALARIA/

Currently recommended prophylactic regimens for Plasmodium falciparum malaria are associated with a high incidence of adverse events and/or suboptimal efficacy. In a double-blind, placebo-controlled, randomized clinical trial in western Kenya, adult volunteers received a treatmen t course of atovaquone/proguanil hydrochloride (250 mg/100 mg per tabl et) to eliminate preexisting infection. Immediately thereafter, subjec ts were randomized to one of the three prophylactic regimens to receiv e one atovaquone/proguanil tablet daily (n = 68), two atovaquone/progu anil tablets daily (n = 65), or placebo (n = 65) for 10 weeks. The stu dy endpoint for any subject was the development of parasitemia, eviden t on blood smear, during prophylaxis. Of the evaluable subjects, all i n the low-dose (54 of 54) and high-dose (54 of 54) atovaquone/proguani l groups remained malaria-free during the 10-week prophylaxis period, in contrast to only 48% (26 of 54) in the placebo group (P < .001). Bo th atovaquone/proguanil prophylactic regimens were as well tolerated a s placebo. Thus, atovaquone/proguanil appears to be highly efficacious and safe as prophylaxis for P. falciparum malaria.