CTSB and ancylostomiasis: Here, we report the striking therapeutic effect of the Clan CA (MEROPS nomenclature [34]) cysteine protease inhibitor (CPI), K11777 (N-methyl-piperazine-phenylalanyl-homophenylalanyl-vinylsulfone phenyl), in a well-established animal model of hookworm infection [31], [35], [36], [37], [38] that employs the golden Syrian hamster and A. ceylanicum.