Phase IIb Clinical Study to Assess the Efficacy and Safety of GenSci120 Injection in Patients With Moderately to Severely Active RA Who Have an Inadequate Response to at Least One DMARD

Inclusion Criteria: 1. Participants who voluntarily sign an informed consent form before the start of activities related to this study, understand the procedures and methods of this study, and are willing to strictly follow the clinical study protocol to complete this study; 2. Male or female participants aged 18- 70 years (inclusive) when signing the informed consent form; 3. Participants diagnosed with RA according to the 2010 RA classification criteria of the American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR), with ACR functional classification Class I-III at screening; 4. Moderately to severely active RA is defined as TJC ≥ 6 and SJC ≥ 6 at screening and baseline based on 68/66 joint counts, and ESR or C-reactive protein (CRP)/hsCRP exceeding the upper limit of normal at screening. Joints with major surgery history will not be included in TJC and SJC; Exclusion Criteria: 1. Known allergy to any component in the GenSci120 formulation, or a history of allergic reactions to any drugs, compounds, foods, or other substances, or a history of hypersensitivity. 2. Any autoinflammatory disease or autoimmune disease (excluding secondary Sjogren's syndrome) other than RA, including but not limited to psoriatic arthritis, inflammatory bowel disease, ankylosing spondylitis, systemic lupus erythematosus, systemic sclerosis or idiopathic inflammatory myopathy, multiple sclerosis or other central demyelinating diseases, primary Sjogren's syndrome, immunodeficiency syndrome, etc; 3. Other joint disorders which could interfere with the assessment of joint disease activity according to the investigators' judgement, such as severe osteoarthritis; 4. History of lymphoproliferative disorders, such as lymphoma, or presence of signs or symptoms of lymphoproliferative disorders, including abnormal lymph node enlargement or hepatosplenomegaly; 5. Those with malignant disease or with a history of malignant disease;