Inclusion Criteria: - Chronic atopic dermatitis (AD) diagnosed according to the Eichenfield modification of Hanifin's and Rajka's (E-HR) criteria at Screening - Disease duration of at least 24 months since diagnosis by any criteria - Documented history of inadequate control of AD by a stable regimen (≥ 4 weeks) of topical corticosteroids, calcineurin inhibitors or biologics, within 6 months of randomization, or inappropriateness of therapy due to side effects or safety risks leading to prior discontinuation - Application of fixed doses of an additive-free, basic bland emollient twice-daily for ≥ 7 days before baseline visit and for the duration of the study Exclusion Criteria: - Any major illness/condition or evidence of an unstable clinical condition or local active infection/infectious illness that, in the investigator's judgment, will substantially increase the risk to the participant if he or she participates in the study or interfere with the interpretation of study results - Clinically relevant cardiovascular conditions or pulmonary conditions - High likelihood - based on participant history, and investigator judgement - of requiring rescue therapy in < 4 weeks prior to randomization - Evidence of acute flare between the Screening and Baseline/ Randomization - Skin lesion(s) and/or pruritus due to conditions other than AD that would interfere with the study specified assessments Other protocol-defined inclusion/exclusion criteria apply