This is a randomized, double-blind, placebo-controlled clinical trial with 500 participants. In this study, the safety evaluation used the common toxic reaction criteria of the National Cancer Institute to evaluate the adverse events of the drugs, and the effectiveness evaluation used the eczema area and severity score and the overall investigator score to confirm the efficacy.

Inclusion Criteria:

• The age of signing the informed consent is 18-75 years old, regardless of gender.
• Meet the 2014 American Academy of Dermatology (AAD) standards, diagnosed as AD.
• During screening and baseline visit, eczema area and severity score (EASI) ≥16 points; Investigator global score (IGA) ≥3 points; Affected body surface area (BSA) ≥10%; Baseline pruritus Peak Value Scale (NRS) weekly mean ≥4 points.
• Have received at least 4 weeks of moderate-to-strong action or at least 2 weeks of super effective external glucocorticoid (TCS) treatment or sufficient duration of systemic glucocorticoid treatment, the efficacy is not sufficient; Or subjects cannot receive the above treatment due to adverse reactions or potential risks.

Exclusion Criteria:

• Used immunosuppressants/immunomodulatory drugs, ultraviolet phototherapy, systemic Chinese medicine treatment within 4 weeks before randomization.
• Received topical calcineurin inhibitors (TCS), topical calcineurin inhibitors (TCI), and other topical preparations within 2 weeks before randomization.
• Received anti-interleukin-4 receptor alpha (IL-4R) monoclonal antibodies, anti-ige monoclonal antibodies, or other biologic agents within 12 weeks or 5 half-lives (whichever is longer) prior to randomization.
• Had received live attenuated vaccine within 12 weeks prior to randomization or planned to receive it during the study period.
• Use of antihistamines within 1 week prior to randomization (unless you have received steady doses of antihistamines for at least 7 days).
• Received allergen specific immunotherapy within 6 months before randomization.
• There are skin comorbidities that may interfere with study evaluation.
• There is a history of clinically significant illness that the investigator believes poses a risk to the safety of the subject and is poorly controlled.
• A known or suspected history of immunosuppression (immune deficiency).
• Subjects with any type of active malignancy or a history of malignancy (except cervical cancer or non-metastatic cutaneous squamous cell carcinoma, basal cell carcinoma, and papillary thyroid carcinoma that have been cured for more than 5 years prior to the screening period).
• Subject may have active Mycobacterium tuberculosis infection.
• Subjects with severe liver and kidney function impairment.
• Screening period HIV antibody positive, or have a history of HIV infection.
• Screening period of treponema pallidum antibody positive.
• Participated in clinical trials of other drugs or medical devices within 12 weeks prior to randomization.
• Treatment-requiring infections were present in the 4 weeks prior to randomization.
• During the study period, subjects plan to undergo major surgical operations.
• Pregnant or lactating women.
• Alcohol, drug abuse and known drug dependence.
• History of atopic keratoconjunctivitis with corneal involvement.
• The subject has any medical or psychiatric symptoms that interfere with participation in the study or with the interpretation of the study results.