The primary objective of this study is to evaluate the efficacy of multiple-dose HSK47388 versus placebo in participants with moderate-to-severe plaque psoriasis.

Inclusion Criteria:

1. Confirmed diagnosis of plaque psoriasis with a disease duration of at least 26 weeks before the first administration of the study intervention
2. Total Body Surface Area (BSA) involvement ≥ 10% at both screening and baseline visits
3. Psoriasis Area and Severity Index (PASI) total score ≥ 12 at both screening and baseline visits
4. Investigator Global Assessment (IGA) for plaque psoriasis total score ≥ 3 (moderate or severe disease) at both screening and baseline visits
5. Participants deemed appropriate candidates for systemic therapy for plaque psoriasis

Exclusion Criteria:

1. Non-plaque psoriasis (e.g., erythrodermic, guttate, or pustular psoriasis)
2. Current drug-induced psoriasis
3. Current diagnosis, signs, or symptoms of severe, progressive, or uncontrolled disease involving the renal, hepatic, cardiac, vascular, pulmonary, gastrointestinal, endocrine, neurologic, hematologic, rheumatologic, psychiatric, or metabolic systems
4. Known allergy, hypersensitivity, or intolerance to HSK47388。
5. A history of malignant tumor before screening;
6. Subjects deemed unsuitable for participation due to other factors as determined by the investigator