Advances in bumped kinase inhibitors for human and animal therapy for cryptosporidiosis

[Display omitted] •Bumpked kinase inhibitor (BKI) 1369 selectively targets Cryptosporidium parvum calcium-dependent protein kinase 1.•It is more potent than nitazoxanide against Cryptosporidium hominis and three strains of C. parvum.•Two identified metabolites have no cytotoxicity against mammalian cell lines.•Pharmacokinetic, safety and efficacy studies support BKI 1369 use as therapy for human and animal cryptosporidiosis. Improvements have been made to the safety and efficacy of bumped kinase inhibitors, and they are advancing toward human and animal use for treatment of cryptosporidiosis. As the understanding of bumped kinase inhibitor pharmacodynamics for cryptosporidiosis therapy has increased, it has become clear that better compounds for efficacy do not necessarily require substantial systemic exposure. We now have a bumped kinase inhibitor with reduced systemic exposure, acceptable safety parameters, and efficacy in both the mouse and newborn calf models of cryptosporidiosis. Potential cardiotoxicity is the limiting safety parameter to monitor for this bumped kinase inhibitor. This compound is a promising pre-clinical lead for cryptosporidiosis therapy in animals and humans.