ATOVAQUONE AND RIFABUTINE-LOADED NANOCAPSULES - FORMULATION STUDIES

Atovaquone and rifabutine have potential therapeutic activity against toxoplasmosis but the low water solubility of these drugs reduces thei r bioavailability. Their formulation as a colloidal suspension of poly (D,L) lactic acid nanocapsules can increase that effectiveness. The a tovaquone formulation was more stable than the rifabutine one and was injected at 15 mg/kg per day by the intragastric route to mice infecte d with Toxoplasma gondii. A better survival rate was observed in mice treated with nanocapsules than in mice treated with a suspension of th e drug. Parasites were undetectable in brains of mice treated with ato vaquone nanocapsules one month previously whereas control mice treated with drug suspension showed signs of central nervous system infection . (C) 1997 Elsevier Science B.V.