Phase IIa Study of Pharmacokinetics, Safety and Efficacy of QY201 Tablets in Adolescent Subjects With Moderate to Severe Atopic Dermatitis

Inclusion criteria

• . The participant and their parent/legal guardian (if applicable) shall have effective communication with the investigator, fully understand the purpose, nature, methods and potential adverse reactions of this trial, comprehend and comply with all requirements of the study, and sign the Informed Consent Form (ICF) prior to initiation of any study procedures.
• . Age ≥12 years and \<18 years (calculated based on the date of ICF signature), any gender, body weight ≥40 kg.
• . Has a documented history of atopic dermatitis (AD) for at least 6 months at screening, and meets the Hanifin-Rajka diagnostic criteria at screening.
• . Meets criteria for moderate to severe AD at screening and baseline:
• . Within 6 months prior to screening, documented evidence of inadequate response to or intolerance of topical therapies including topical corticosteroids (TCS) and/or topical calcineurin inhibitors (TCI); or documented indication for systemic therapy (e.g., systemic corticosteroids, conventional immunosuppressants, biologics, JAK inhibitors, etc.) for disease control.
• . The participant is able and willing to regularly apply fragrance-free and inactive-ingredient-free emollients twice daily for at least 7 consecutive days prior to randomization, and continue such application throughout the study period.
• . Participants of childbearing potential (females post-menarche, males post-spermarche) must agree to and implement effective contraception from the date of ICF signature through 3 months after the last study drug administration. For female participants of childbearing potential, serum human chorionic gonadotropin (HCG) test shall be negative at screening, and the subject must not be breastfeeding.