Activities ofN,N′-Diarylurea MMV665852 Analogs against Schistosoma mansoni

Abstract

ABSTRACTThere is an unmet need to discover and develop novel antischistosomal drugs. As exemplified by MMV665852,N,N′-diarylureas have recently emerged as a promising antischistosomal chemotype. In this study, we evaluated the structure-activity relationships of 46 commercially available analogs of MMV665852 on newly transformed schistosomula (NTS) and adultSchistosoma mansoniwormsin vitro. Active compounds were evaluated with a cytotoxicity assay,in silicocalculations, metabolic stability studies, and anin vivoassay with mice harboring adultS. mansoniworms. Of the 46 compounds tested at 33.3 μM, 13 and 14 compounds killed NTS and adult worms, respectively, within 72 h. Nine compounds had 90% inhibitory concentrations (IC90s) of ≤10 μM against adult worms, with selectivity indexes of ≥2.8. Their physicochemical properties and permeation through an artificial membrane indicated good to moderate intestinal absorption. Their metabolic stabilities ranged from low to high. Despite satisfactoryin vitroresults andin silicopredictions, only one compound resulted in a statistically significant worm burden reduction (66%) after administration of a single oral dose of 400 mg/kg of body weight toS. mansoni-infected mice. Worm burden reductions of 0 to 43% were observed for the remaining eight compounds tested. In conclusion, several analogs of theN,N′-diarylurea MMV665852 had high efficacy againstS. mansoniin vitroand favorable physicochemical properties for permeation through the intestinal wall. To counteract the low efficacy observed in the mouse model, further investigations should focus on identifying compounds with improved solubility and pharmacokinetic properties.