Study of HXN6005 in Healthy Participants and Patients With Moderate-to-Severe Atopic Dermatitis

Inclusion Criteria:

1. Participants must be able to understand and comply with the study requirements and voluntarily sign the informed consent form (ICF).
2. (Healthy Participants) Male or female participants aged 18 to 55 years (inclusive) at the time of signing the ICF.
3. (Healthy Participants) Male participants weighing ≥ 50.0 kg and female participants weighing ≥ 45.0 kg, with a body mass index (BMI) between 18.0 and 28.0 kg/m² (inclusive).
4. (Patients with AD) Male or female participants aged 18 to 70 years (inclusive) .
5. (Patients with AD) Participants must have documented AD history, moderate-to-severe disease, and inadequate response to topical therapy at screening.

Exclusion Criteria:

1. Presence of any clinically significant disease at randomization, as judged by the investigator.
2. Known or suspected allergy or intolerance to any component or excipient of HXN6005 injection or placebo.
3. History of severe drug allergy or systemic anaphylactic reactions, such as anaphylactic shock, laryngeal edema, etc.
4. Known or suspected history of immunosuppression, or history of invasive opportunistic infections, including infections that are unusually frequent, recurrent, or prolonged in duration as judged by the investigator, even after resolution of the infection.
5. History of malignancy or malignant disease, with the exception of surgically excised cutaneous squamous cell carcinoma in situ, basal cell carcinoma, and cervical carcinoma in situ that have been in complete remission for more than 5 years without any evidence of recurrence.