The study is a phase I, single center, double-blind, placebo-controlled dose finding clinical study to evaluate the safety, tolerability and immunogenicity of the live attenuated, oral vaccine ACE527. The study is designed to evaluate 2 doses of the ACE527 in 2 cohorts. Each cohort will consist of approximately 18 subjects (healthy subjects), approximately 12 of them receiving ACE527 and approximately 6 receiving placebo.~Within a cohort, the second dose will only be given if safety and tolerability of the first dose is acceptable. This assessment will be based on evaluation of data up until Day 7 by the Independent Safety Committee (ISC) as per written guidance. The first dose of each cohort will be administered during an inpatient stay. Escalation to the next dose level will be dependent on an acceptable safety profile of the first dose at the previous dose level, based on evaluation of safety data by an Independent Safety Committee (ISC). The decision to administer the second dose at the higher level will also require review of the safety and tolerability of the second dose at the lower level.~The second dose will be administered at the outpatient clinic and the subjects will be observed for at least 60 minutes after vaccination prior to discharge from unit.
The purpose of this study is to evaluate the safety and immune response to ACE527.