Activity of artemether and mefloquine against juvenile and adult Schistosoma mansoni in athymic and immunocompetent NMRI mice.

Immune effector mechanisms can enhance the activity of antischistosomal drugs. We examined the in vivo effect of single oral doses of the antimalarials artemether (400 mg/kg) and mefloquine (200 mg/kg), recently described to have promising antischistosomal properties, against juvenile and adult Schistosoma mansoni in T cell-deficient and in comparably infected age- and sex-matched immunologically intact control mice. Artemether and mefloquine are equally effective in athymic and immunocompetent mice. Artemether treatment resulted in total and female worm burden reductions ranging between 71.1% and 85.3%, whereas mefloquine achieved total and female worm burden reductions of 80.4-97.8%. In conclusion, artemether and mefloquine act T-cell independently and no synergistic interaction with the immune response was involved.