Study of ADSTEM Injection for Patients With Moderate to Severe Subacute and Chronic Atopic Dermatitis

Inclusion Criteria: 1. Adults aged 19 to 70 years at the time of informed consent. 2. Diagnosis of atopic dermatitis according to the Hanifin and Rajka criteria at screening. 3. History of atopic dermatitis for at least 24 weeks prior to screening. 4. Moderate-to-severe atopic dermatitis at screening, defined as: * EASI score ≥16 * SCORAD score ≥25 * Body Surface Area (BSA) involvement ≥10% * vIGA score ≥3 5. Inadequate response to prior standard topical and/or systemic treatments for atopic dermatitis, or inability to receive such treatments due to safety concerns. 6. Voluntary written informed consent provided. Exclusion Criteria: 1. Presence of clinically significant comorbidities at screening, including: * Active infection requiring antimicrobial treatment within 2 weeks prior to baseline, or superficial skin infection within 1 week prior to baseline; * Skin diseases that require ongoing treatment or may interfere with safety or efficacy assessments; * Uncontrolled asthma requiring oral corticosteroids; * Positive test results for hepatitis B virus (HBV), hepatitis C virus (HCV), human immunodeficiency virus (HIV), or syphilis; * Other uncontrolled or clinically significant medical conditions that may affect study participation or assessments; * Clinically significant abnormal laboratory results at screening (e.g., AST or ALT \> 3 × ULN, serum creatinine \> 2 × ULN). 2. History of prohibited treatments prior to baseline, including: * Use of JAK inhibitors within 4 weeks; * Use of biologic therapies for atopic dermatitis within 12 weeks; * Use of systemic immunosuppressants, immunomodulators, or systemic corticosteroids within 4 weeks; * Use of topical corticosteroids, topical PDE-4 inhibitors, or topical calcineurin inhibitors within 2 weeks; * Participation in another clinical trial with an investigational drug or device within 4 weeks prior to screening; * Prior treatment with cell therapy or gene therapy. 3. History of malignancy within 5 years prior to screening, except adequately treated non-melanoma skin cancer without recurrence. 4. History of tanning within 4 weeks prior to baseline. 5. Pregnant or breastfeeding women, or women planning pregnancy during the study period. 6. Women of childbearing potential who are unwilling to use adequate contraception from the time of informed consent through the end of the study. 7. Known or suspected hypersensitivity to the investigational product or any of its components. 8. Any other condition that, in the investigator's judgment, makes the participant unsuitable for participation in the study.