A Study of Lebrikizumab (LY3650150) in Combination With Topical Corticosteroids in Japanese Participants With Moderate-to-Severe Atopic Dermatitis

Inclusion Criteria: * Have chronic Atopic Dermatitis (AD) that has been present for ≥1 year before the screening. * Have moderate-to-severe AD, including all of the following: * EASI score ≥16 at the baseline * IGA score ≥3 (scale of 0 to 4) at the baseline * AD involvement on ≥10% of Body Surface Area (BSA) at the baseline * Have a documented history provided by a physician and/or investigator of inadequate response to existing topical medications within 6 months preceding screening as defined by at least 1 of the following: * Inability to achieve good disease control, defined as mild disease or better (for example, IGA ≤2) after use of at least a medium-potency topical corticosteroids (TCS) for at least 4 weeks, or for the maximum duration recommended by the product prescribing information (for example, 14 days for super-potent TCS), whichever is shorter. Topical corticosteroids may be used with or without Topical calcineurin inhibitors (TCI) and/or topical Janus Kinase (JAK) inhibitors. * Participants who failed systemic therapies intended to treat AD within 6 months preceding screening, such as cyclosporine, methotrexate (MTX), azathioprine, and mycophenolate mofetil (MMF), will also be considered as surrogates for having inadequate response to topical therapy. * Body weight ≥40 kilogram (kg) Exclusion Criteria: * Have a history of anaphylaxis * Have uncontrolled chronic disease that might require bursts of oral corticosteroids for example, comorbid severe uncontrolled asthma within the past 12 months requiring systemic corticosteroid treatment or hospitalization for \>24 hours at baseline. * Have an active chronic or acute infection requiring treatment with systemic antibiotics, antivirals, antiparasitics, antiprotozoals, or antifungals within 2 weeks before the baseline or superficial skin infections within 1 week before the baseline. * Evidence of acute or chronic hepatitis or known liver cirrhosis. * Have a history of pneumocystis pneumonia (PCP) or a positive beta-D-glucan test at screening and a confirmed diagnosis of PCP. * Have a history of human immunodeficiency virus (HIV) infection or positive HIV serology at screening. * Have presence of skin comorbidities (for example, sclerosis, psoriasis, or lupus erythematosus) that may interfere with study assessments. * Have presence of significant uncontrolled neuropsychiatric disorder. * Have been exposed to a live vaccine within 12 weeks prior to baseline or are expected to need/receive a live vaccine during the study or up to 125 days after the last dose of study drug.