A Study to Evaluate the Equivalence of IBI3027 and Dupilumab Injection in Participants With Moderate to Severe Atopic Dermatitis

Key inclusion criteria: 1. Understand the requirements and process, voluntarily participate in clinical trials and sign consent, willing and able to comply with the requirements of protocol; 2. Male or female participants aged 18 to 75; 3. AD diagnosis at screening meeting the Hanifin-Rajka criteria, and the course of AD ≥ 1 year before screening as judged by the investigator; 4. Moderate to severe AD at screening and baseline, meeting all the following criteria: a. IGA score ≥ 3; b. EASI score ≥ 16; c. BSA≥10%; 5. Average daily PP-NRS score within 7 days prior to randomization ≥ 4 points; 6. As assessed by investigator, records indicating poor treatment response with topical local medications, or not suitable for topical treatment due to other medical reasons (such as severe adverse reactions or safety risks, etc.), within 6 months prior to the screening Key exclusion criteria： 1. Have active skin diseases that may affect the assessment of AD (such as psoriasis or lupus erythematosus), or other skin complications caused by other diseases. Those who are in an acute exacerbation state of AD at the time of randomization (such as participants having rapidly progressing erythroderma or a tendency towards erythroderma, as assessed by the investigators); 2. Have history of active spring keratoconjunctivitis (VKC) and atopic keratoconjunctivitis (AKC) within 6 months prior to screen; 3. Suspected immunosuppressive disease within 6 months prior to screen; 4. Within 2 weeks prior to screen, systemic use of antimicrobial treatment (for viral, bacterial, fungal, or parasitic infections) or having superficial skin infections (such as impetigo); 5. Participants at high risk of infection; 6. Within 1 year prior to screen, recurrent herpes zoster or Kaposi's varicelliform eruption (≥ 2 times), disseminated herpes zoster or disseminated herpes simplex; 7. Positive for human immunodeficiency virus (HIV) antibody; 8. Participants with syphilis infection; 9. Positive for the hepatitis C virus (HCV) antibody and HCV RNA (if HCV antibody positive); 10. Positive for hepatitis B surface antigen (HBsAg) and HBV-DNA (if HBsAg positive); 11. Previous use IL-4 and/or IL-13 targeting drugs (such as dupilumab, etc.) for the treatment of AD with no response or poor efficacy; 12. Systemic use of IL-4Rα or IL-13 antibody treatment ≤ 3 months or 5 half-lives (if the half-life is known) prior to randomization; 13. ≥ 2 bleach baths ≤ 2 weeks prior to randomization; 14. Use of drugs containing main active ingredients such as compound glycyrrhizin or total polysaccharides of peony ≤ 2 weeks prior to randomization; 15. Following treatments ≤4 weeks prior to randomization: a. systemic use of glucocorticoids or immunosuppressants; b. systemic use of traditional Chinese medicine; c. calcium channel-based anti-epileptic drugs, anti-serotonin agents, and opioid receptor antagonists, with antipruritic effects; d. ultraviolet therapy. 16. Treatment of allergen-specific immunotherapy ≤ 6 months prior to randomization; 17. Use of any cell depletion agents including but not limited to rituximab ≤12 months prior to randomization.