To Evaluate the Efficacy and Safety of SG301 SC Injection in Systemic Lupus Erythematosus

Prior treatment

• Previous use of CD38 or monoclonal antibodies targeting CD38.
• Active central nervous system (CNS) disease within 2 months before the first dose, or CNS disease that the investigator believes may require treatment with prohibited therapies specified in the protocol.
• Participation in any other clinical trial within 4 weeks before the first dose (excluding participants who provided informed consent but did not receive trial treatment, or only received placebo).
• Receipt of any B cell-depleting drugs (such as belimumab, telitacicept) within 4 weeks or 5 half-lives (whichever is shorter) before the first dose.
• Receipt of JAK inhibitor treatment within 2 weeks before the first dose.

Other illness

• Diagnosis of mixed connective tissue disease or a history of any overlap syndrome between SLE and systemic sclerosis.
• Current acute or chronic infection meeting any of the following criteria.
• Presence of severe cardiovascular and cerebrovascular diseases.
• Mycobacterium tuberculosis infection.
• Presence of HIV infection, active hepatitis B, or hepatitis C.
• Known history of active syphilis.
• History of major organ transplantation (e.g., heart, lung, kidney, liver) or hematopoietic stem cell/or bone marrow transplantation.
• Other conditions that the investigator believes would prevent the participant from participating in the study.

Lab values

• Laboratory abnormalities.
• Use of any targeted T or B lymphocyte drugs (e.g., rituximab) within 3 months before the first dose.

• Voluntarily participate in the clinical study and sign a written informed consent form.
• Participants must be diagnosed with SLE in accordance with the 2019 European League Against Rheumatism (EULAR)/American College of Rheumatism (ACR) SLE classification criteria and have inadequate response to standard treatment, intolerance to standard treatment, or recurrent disease.
• SLEDAI-2K score ≥ 8 points, with clinical features corresponding to a SLEDAI-2K score ≥ 4 points.
• Positive serological test results for autoantibodies, defined as antinuclear antibody (ANA) positivity and/or anti-double-stranded DNA (anti-dsDNA) antibody positivity.
• Body weight ≥ 35 kg.
• Must have received standard treatment for at least 8 weeks before the first dose and maintained a stable dose of the treatment unchanged for at least 4 weeks before the first dose.
• Participants of childbearing potential or whose partners are of childbearing potential must agree to use effective contraceptive measures throughout the entire study period and within 6 months after the last dose.