A novel antifungal drug candidate, 1-tetrazole VT-1161 [(R)-2-(2,4-difluorophenyl)-1,1-difluoro-3- (1H-tetrazol-1-yl)-1-(5-(4-(2,2,2-trifluoroethoxy)phenyl)pyridin-2-yl)propan-2-ol], which is currently in two Phase 2b antifungal clinical trials, was found to be a tight-binding ligand (the apparent dissociation constant (Kd) = 24 nM) and a potent inhibitor of cytochrome P450 sterol 14α- demethylase (CYP51) from the protozoan pathogen Trypanosoma cruzi. Moreover, VT-1161 revealed high antiparasitic efficiency in cellular experiments against amastigotes of the Tulahuen strain of T. cruzi (EC50=2.5 nM) and was active in vivo, causing >99.8% of peak parasitemia suppression in a mouse model of infection with the naturally drug-resistant Y strain of the parasite. The data strongly support the potential utility of VT-1161 in the treatment of Chagas disease. Structural characterization of T. cruzi CYP51 in complex with VT-1161 provides insights into the molecular basis for the compound inhibitory potency and paves the way for further rational development of this novel, tetrazole-based inhibitory chemotype, both for antiprotozoan, and for antifungal chemotherapy