This is a Phase I, randomized, double-blind, placebo-controlled single ascending dose study of orally administered ALLN-346. The study will evaluate the safety and tolerability, inflammation and immunogenicity, pharmacokinetics and pharmacodynamics of ALLN-346 in healthy volunteers. The study consists of a Screening Period, a Treatment Period of 3 days, which includes 1 single day of dosing and 3 days of in-house observation, and a safety Follow-up Period through Day 28 following dosing.