This study has the purpose to demonstrate prospect of benefit of EDI048 on clinical signs and symptoms of cryptosporidiosis to facilitate trial in target population, pediatric patients. This study aims to investigate the efficacy of a new chemical entity, EDI048, in a controlled human infection model of cryptosporidiosis induced by administration of ABO809 in healthy adults, who become symptomatic with disease thereby demonstrating a prospect of benefit for use of EDI048 in children afflicted with cryptosporidiosis.