This trial was designed to evaluate the safety of SHR-1819 in children and adolescents with moderate-to-severe atopic dermatitis.

Inclusion Criteria:

1. Subjects and their parents or legal guardians have voluntarily signed the informed consent form prior to the start of any procedures related to the study, are able to communicate smoothly with the investigator, understand and are willing to strictly comply with the requirements of this clinical study protocol to complete the study;
2. At the time of signing the informed consent, the subjects were ≥ 6 years old and < 18 years old, male or female;
3. Have atopic dermatitis at screening.

Exclusion Criteria:

1. Before enrollment, the subjects weighed < 15kg;
2. Females who are pregnant or lactating and have a positive pregnancy test result;
3. Have other active skin disease or skin complications due to other conditions that may affect the evaluation of AD;
4. Have serious concomitant diseases and other conditions that the investigator considers inappropriate to participate in this trial;
5. Treated with biologics targeting IL-4Rα , or participated in previous clinical studies of biologics targeting IL-4Rα, including SHR-1819 injection;
6. Has malignancy or has a history of malignancy;
7. Hypersensitivity to the study drug or any ingredient in the study drug.