Blood schizontocidal activity of methylene blue in combination with antimalarials againstPlasmodium falciparum

Giovanny Garavito (1, 2) , Stephane Bertani (1, 3) , Javier Rincon (2) , Séverine Maurel (1) , Marie-Carmen Monje (1) , Irene Landau (3) , Alexis Valentin (1) , Eric Deharo (1)

1 PHARMA-DEV - Pharmacochimie et Biologie pour le Développement
2 UNAL - Universidad Nacional de Colombia [Bogotà]
3 MNHN - Muséum national d'Histoire naturelle

Methylene blue (MB) is the oldest synthetic antimalarial. It is not used anymore as antimalarial but should be reconsidered. For this purpose we have measured its impact on both chloroquine sensitive and resistant Plasmodium strains. We showed that around 5 nM of MB were able to inhibit 50% of the parasite growth in vitro and that late rings and early trophozoites were the most sensitive stages; while early rings, late trophozoites and schizonts were less sensitive. Drug interaction study following fractional inhibitory concentrations (FIC) method showed antagonism with amodiaquine, atovaquone, doxycycline, pyrimethamine; additivity with artemether, chloroquine, mefloquine, primaquine and synergy with quinine. These results confirmed the interest of MB that could be integrated in a new low cost antimalarial combination therapy.

Mots clés: Antimalarials; Plasmodium; Methylene blue; Drug interactions

Domaines: Génie chimique; Génie des procédés

Giovanny Garavito, Stephane Bertani, Javier Rincon, Séverine Maurel, Marie-Carmen Monje, et al.. Blood schizontocidal activity of methylene blue in combination with antimalarials againstPlasmodium falciparum. Parasite, 2007, 14 (2), pp.135-140. ⟨10.1051/parasite/2007142135⟩. ⟨hal-02143176⟩