The purpose of this study is to evaluate the efficacy and safety of IMC-002 and IMM0306S in the treatment of active SLE.

This two-stage study consists of a multicenter dose-escalation study（Phase Ib）and a multicenter randomized, double-blind, placebo-controlled study（Phase II）.

Primary objectives of the dose-finding stage: 1) Evaluate the efficacy, safety, pharmacokinetic (PK) and pharmacodynamic (PD) profiles of intravenous IMC-002 and subcutaneous IMM0306S in adult patients with active systemic lupus erythematosus (SLE); 2) Determine the absolute bioavailability of subcutaneous IMM0306S relative to intravenous IMC-002 in adults with moderate-to-severe active SLE; 3) Select the recommended Phase II dose (RP2D).

Primary objectives of the proof-of-concept (PoC) stage: Compare the efficacy of 1.2 mg/kg or 1.6 mg/kg IMC-002 versus placebo in adults with moderate-to-severe active SLE, and assess the efficacy and population PK (popPK) profiles of IMM0306S in patients with active SLE.

Inclusion Criteria:

• Has had a diagnosis of SLE for at least 12 weeks prior to the screening Visit.
• SLEDAI-2000 score ≥8. For screening eligibility only, headache and fever items shall be excluded from SLEDAI-2K scoring. Skin lesions shall meet morphological and distributive characteristics of active cutaneous lupus, with a total active Cutaneous Lupus Erythematosus Area and Severity Index (CLASI) score ≥2.
• BILAG-2004 organ system scores of at least 1 A or 2 B at screening.
• Currently receiving at least one of the SOC SLE medications: oral corticosteroid, antimalarial and/or immunosuppressive agent.
• Other protocol defined inclusion criteria may apply.

Exclusion Criteria:

• Active or unstable neuropsychiatric SLE or lupus nephritis
• Autoimmune or rheumatic disease other than SLE
• Significant, uncontrolled medical conditions not related to SLE
• Active and/or severe viral, bacterial or fungal infection
• History of malignancy within 5 years
• Other protocol defined exclusion criteria may apply.