ACE1831 in Adult Subjects With Relapsed/Refractory Systemic Lupus Erythematosus （SLE）

Inclusion Criteria: * Male or female 18 to 60 years (inclusive) * History of meeting the 2019 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) criteria, or the 1997 ACR criteria, or the 2012 Systemic Lupus International Collaborating Clinics (SLICC) * Presence of anti-dsDNA antibodies and/or anti-nuclear antibodies (ANA) and/or anti-Smith (anti-Sm) antibodies positive * SLE is in the moderate to severe active phase with the SLEDAI-2000 score ≥ 8 * At least one British Isle Lupus Rating Group Index (BILAG-2004) Class A (severe manifestation) or two Class B (moderate manifestation) organ scores, or both * Inadequate response to glucocorticoids and at least 2 of treatments used for at least 3 months * Women of childbearing potential and their partners must agree to use at least 1 highly effective method of contraception throughout the study period and for 1 year after treatment * Signed informed consent Exclusion Criteria: * Severe lupus nephritis requiring prohibited medications for active nephritis treatment，or hemodialysis, or eGFR \< 50 ml/min/1.73m² * Central nervous system disease caused by SLE or other conditions * Significant medical history that would pose a risk to the patients safety from the investigator's opinion, or patients medical condition could worsen during the study * Malignancies within 5 years * Presence of active, recurrent, chronic infection requiring treatment , or latent infection (HBV, HCV, HIV, TB, syphilis) * Received any B-cell depletion biologic therapy * Received immunosuppressive small molecule drug therapy， or other systemic corticosteroid therapy ， or prednisone * Pregnant or lactating women