A Safety, Tolerability and Preliminary Efficacy Study of FRTX-02 Capsules in Healthy Subjects and Subjects With Atopic Dermatitis

Selected Inclusion Criteria Part 1 (SAD/MAD) * Healthy male or female * 18-55 years of age, inclusive * At least 50 kg in weight (males) and 45 kg in weight (females) * BMI 18.5-30.0 kg/m2, inclusive Part 2 (Subjects with AD) * Male or female with atopic dermatitis * 18-65 years of age, inclusive * BMI 18-40.0 kg/m2, inclusive * Validated Investigator's Global Assessment (vIGA-AD) score of ≥ 3 (moderate) * Body surface area (BSA) with AD involvement ≥ 10% * History of inadequate response to treatment with topical medications (e.g., corticosteroids, calcineurin inhibitors, etc.) or subjects for whom topical treatments are otherwise medically inadvisable. Selected Exclusion Criteria Part 1 (SAD/MAD) * Use of tobacco products within 3 months prior to drug administration * History of alcohol abuse or drug abuse * Positive urine drug screen, alcohol breath test, or urine cotinine test * Participation in a clinical research study involving the administration of an investigational or marketed drug within 30 days prior to drug administration * Donation of plasma within 7 days prior to dosing or donation or loss of 500 mL or more of whole blood within 8 weeks prior to dosing. Part 2 (Subjects with AD) * History of alcohol abuse or drug abuse * Positive urine drug screen, alcohol breath test, or urine cotinine test * Participation in a clinical research study involving the administration of an investigational or marketed drug within 12 weeks prior to drug administration