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

The study consisted of four periods: screening period (up to 4 weeks), induction period (12 weeks), maintenance period (40 weeks) and follow-up period (8 weeks). This study planned to recruit 702 subjects, who were randomized into JS005 300mg group (234 subjects), JS005 150mg group (234 subjects) and placebo group (234 subjects) at a ratio of 1:1:1, and were stratified by whether they had previsouly received biologic treatments (continuous biologic treatment for ≥3 months at recommended doses or intolerance for safety reasons) and body weight (≥70 kg or < 70 kg).

Inclusion criteria

• Subjects voluntarily particpate in this clinical study and sign the informed consent form.
• Male and female patients aged 18-75 years at the time of screening (both inclusive).
• Fertile female subjects must be willing to use a highly effective contraceptive method during the study period and 20 weeks (expected 5 half-lives) after the last study drug administration and have a negative pregnancy test during the screening period and prior to randomization.

Exclusion criteria

• Pregnant and lactating women.
• A history of inflammatory bowel disease or other conditions with a high risk of perforation (e.g., severe gastrointestinal ulcers, etc.) or with other active autoimmune diseases (e.g., systemic lupus erythematosus, Sarcoidosis, etc.).
• Have a type of psoriasis other than chronic plaque psoriasis (e.g., pustular, erythrodermic, and guttate psoriasis), drug-induced psoriasis, or have an active inflammatory skin disease other than psoriasis
• Use of phototherapy, including but not limited to ultraviolet A phototherapy (with or without psoralens), ultraviolet B phototherapy, or excimer laser within 4 weeks prior to randomization. Subjects are unwilling to avoid excessive sunlight exposure within 4 weeks prior to randomization and during the study period;
• A (current) history of systemic infection or serious infection requiring hospitalization and/or intravenous anti-infective therapy (e.g., antibiotics, antifungal agents, antiviral agents) within 12 weeks prior to randomization; a history of any active infection, other than common upper respiratory infections, within 2 weeks prior to randomization;