POTENTIATION OF THE ANTIMALARIAL ACTIVITY OF ATOVAQUONE BY DOXYCYCLINE AGAINST PLASMODIUM-FALCIPARUM IN-VITRO

The effect of doxycycline, obtained from human volunteers administered doxycycline, on the minimum inhibitory concentration (MIC) of atovaqu one was determined against the K1 and FC27 isolates of Plasmodium falc iparum in vitro. Doxycycline concentrations ranging from 0.10-1.18 mu g/ml added to atovaquone produced MIC ratios [atovaquone + doxycycline /atovaquone alone] ranging from 0.38 to 0.70. These results suggest th at the antimalarial activity of atovaquone is potentiated by doxycycli ne. Additionally, these drugs may be rational partners for the treatme nt and prophylaxis of falciparum malaria.