Evaluate the Efficacy and Safety of XKH001 Injection in Patients With Moderate-to-Severe Atopic Dermatitis

"100 mg quaque 4 weeks dose group: Subjects will receive 1 mL (1 vial) of XKH001 injection (100 mg) and 5 mL (5 vials) of placebo injection subcutaneously each time, once every 4 weeks, for a total of 5 times.~300 mg quaque 4 weeks dose group: Subjects will receive 3 mL (3 vials) of XKH001 injection (300 mg) and 3 mL (3 vials) of placebo injection subcutaneously each time, once every 4 weeks, for a total of 5 times.~600 mg quaque 4 weeks dose group: Subjects will receive 6 mL (6 vials) of XKH001 injection (600 mg) subcutaneously each time, once every 4 weeks, for a total of 5 times."

Subjects will receive 6 mL (6 vials) of placebo injection subcutaneously each time, once every 4 weeks, for a total of 5 times.