Proguanil plus sulfamethoxazole in the treatment of uncomplicated Plasmodium falciparum malaria.

In a malaria endemic area of Brazil where P. falciparum is highly resistant to chloroquine and Fansidar, we conducted an in vivo study to evaluate the therapeutic response of proguanil plus sulfametoxazole against Plasmodium falciparum malaria. Twenty-five adult subjects with uncomplicated P. falciparum malaria received supervised drug administration and were followed for 28 days in an inpatient hospital or in a malaria free-transmission area. The therapeutic regimen was proguanil 100 mg BID plus sulfamethoxazole 1,000 mg BID for 7 days. Of those who took all medications (n=21), 17 (81%) were cured. Recrudescent parasitemia during follow-up occurred in four (19%) patients on days 14, 19, 20 and 21 after beginning of treatment. The remaining four (16%) subjects did not complete their therapeutic regimen because the incidence of side effects. Considering the shortage of falciparum malaria therapeutic options and the urgent need for new regimens to deal with the spread of drug resistant P. falciparum, one might consider the study results as a lead to study analogous compounds, hopefully with fewer adverse reactions.