SM101 In systemic lupus erythematosus patients with or without a history of lupus nephritis

INTERVENTION: Three treatment arms, two interventions groups and a placebo in parallel fashion: 1. Intervention group 1: 6 mg/kg/week SM101 for 4 weeks 2. Intervention group 2: 12 mg/kg/week SM101 for 4 weeks 3. Placebo CONDITION: Systemic lupus erythematosus patients with or without a history of lupus nephritis ; Musculoskeletal Diseases ; Systemic lupus erythematosus PRIMARY OUTCOME: Incidence of adverse events (AEs) during the study period according to Common Terminology Criteria for Adverse Events (CTCAE) SECONDARY OUTCOME: 1. Physical examination (screening); 2. Vital signs (screening, treatment, follow‐up); 3. Body temperature (screening, treatment, follow‐up); 4. Body weight (screening, treatment); 5. Electrocardiogram (ECG) (screening, treatment, follow‐up); 6. Safety laboratory assessments (screening, treatment, follow‐up); 7. Anti‐drug antibody (ADA) (treatment, follow‐up); 8. AE recording (continuously); 9. Overall and renal disease score assessments, proteinuria, urine sediment, glomerular filtration rate (GFR), biological markers, anti‐double‐stranded DNA (dsDNA), anti‐C1q, C3, C4, urinary neutrophil gelatinase‐associated lipocalin (uNGAL) (continuously); 10. Use of rescue medication (all during screening, treatment, follow‐up) INCLUSION CRITERIA: 1. Patient has provided written informed consent prior to any study‐related procedure 2. Male or female adult patients aged 18 years or older 3. Diagnosis of SLE meeting at least four revised main classification criteria of the American College of Rheumatology (ACR) with or without a history of glomerulonephritis 4. Clinically active patients with a SLE Disease Activity Index (SELENA‐SLEDAI) score of = 6 5. Patients with a current serological active status (anti‐dsDNA or C3) 6. Concurrent maintenance immunosuppressant SLE treatment (if any) with prednisone alone or in combination with either azathioprine or mycophenolate mofetil 7. Adequate liver function