The intravascular parasitic worm Schistosoma mansoni is a causative agent of
schistosomiasis, a disease of great global public health significance.
Praziquantel is the only drug available to treat
schistosomiasis and there is an urgent demand for new
anthelmintic agents. Adopting a phenotypic drug screening strategy, here, we evaluated the
antiparasitic properties of 46 commercially available
cardiovascular drugs against S. mansoni. From these screenings, we found that
amiodarone,
telmisartan,
propafenone,
methyldopa, and
doxazosin affected the viability of schistosomes in vitro, with effective concentrations of 50% (EC50) and 90% (EC90) values ranging from 8 to 50 µM. These results were further supported by scanning electron microscopy analysis. Subsequently, the most effective drug (
amiodarone) was further tested in a murine model of
schistosomiasis for both early and chronic S. mansoni
infections using a single oral dose of 400 mg/kg or 100 mg/kg daily for five consecutive days.
Amiodarone had a low efficacy in
chronic infection, with the worm and egg burden reduction ranging from 10 to 30%. In contrast,
amiodarone caused a significant reduction in worm and egg burden in early
infection (>50%). Comparatively, treatment with
amiodarone is more effective in early
infection than
praziquantel, demonstrating the potential role of this
cardiovascular drug as an
antischistosomal agent.