Summary: This is a multi-center, Phase 1b, double-blind, placebo-controlled, SAD and MAD, first-in-human study in subjects with mild to severe AD receiving si-544. The study consists of 2 parts, an SAD and an MAD part. In both parts, subjects will be treated in cohorts and will be randomized within each cohort to treatment with si-544 or placebo. Initially, 2 sentinel subjects will be treated (randomized t...