A Phase 2 Study of Recombinant Anti-IL-17A Humanized Monoclonal Antibody in Chinese Participants With Moderate-to-Severe Plaque Psoriasis

Inclusion Criteria: Must be 18 Years to 65 Years, both male and female. BMI ≥18 kg/m^2 and ≤32 kg/m^2 ，and male weight ≥50 kg, female weight ≥45 kg during the screening. Chronic plaque psoriasis (PSO) for at least 6 months prior to the randomizationas as determined by the investigator.. Psoriasis Area Severity Index (PASI) >=12 and body surface area (BSA) affected by PSO >=10% and Static Physician Global Assessment (sPGA) score >=3. According to the judgment of the investigator, the subject needs to receive systemic treatment and / or phototherapy (including subjects who have used local treatment, and / or phototherapy, and / or poor control of previous systemic treatment). Subject must be able to understand and comply with the requirements of the study. and must participate voluntarily and sign the written informed consent. Exclusion Criteria: History of pustular or erythrodermic psoriasis other than plaque psoriasis at screening or baseline. History of drug-induced psoriasis. Ongoing use of prohibited treatments. Have previously received any drug that directly targets IL-17. Have concurrent or recent use of any biologic agent within washout periods or <5 half-lives prior to randomization. Chronic infections including HIV, viral hepatitis (hepatitis B, hepatitis C), syphilis and/ or active tuberculosis. Pregnant or lactating women.