A Clinical Study to Evaluate the Efficacy and Safety of Subcutaneous JS005 Injection in the Treatment of Adults With Moderate to Severe Chronic Plaque Psoriasis

Inclusion Criteria:

1. Subjects voluntarily particpate in this clinical study and sign the informed consentform.

2. Male and female patients aged 18-75 years at the time of screening (both inclusive).

3. Fertile female subjects must be willing to use a highly effective contraceptivemethod during the study period and 20 weeks (expected 5 half-lives) after the laststudy drug administration and have a negative pregnancy test during the screeningperiod and prior to randomization.

Exclusion Criteria:

1. Pregnant and lactating women.

2. A history of inflammatory bowel disease or other conditions with a high risk ofperforation (e.g., severe gastrointestinal ulcers, etc.) or with other activeautoimmune diseases (e.g., systemic lupus erythematosus, Sarcoidosis, etc.).

3. Have a type of psoriasis other than chronic plaque psoriasis (e.g., pustular,erythrodermic, and guttate psoriasis), drug-induced psoriasis, or have an activeinflammatory skin disease other than psoriasis

4. Use of phototherapy, including but not limited to ultraviolet A phototherapy (withor without psoralens), ultraviolet B phototherapy, or excimer laser within 4 weeksprior to randomization. Subjects are unwilling to avoid excessive sunlight exposurewithin 4 weeks prior to randomization and during the study period;

5. A (current) history of systemic infection or serious infection requiringhospitalization and/or intravenous anti-infective therapy (e.g., antibiotics,antifungal agents, antiviral agents) within 12 weeks prior to randomization; ahistory of any active infection, other than common upper respiratory infections,within 2 weeks prior to randomization;