Systemic lupus erythematosus (SLE) is a systemic autoimmune disease characterized by heterogeneous clinical manifestations ranging from mild cutaneous involvement to severe multi-organ damage. While its pathogenesis involves complex cytokine dysregulation, emerging evidence implicates IL-17 as a potential contributor. Elevated serum IL-17 levels have been observed in SLE patients compared to healthy controls, with heightened expression detected in renal and cutaneous lesions. Ustekinumab, a monoclonal antibody targeting IL-23/IL-12 that indirectly modulates IL-17 signaling, demonstrated superior efficacy and safety to placebo in an SLE clinical trial, particularly in glucocorticoid dose reduction. Notably, no clinical trials have directly evaluated IL-17-targeted therapies for SLE, though case reports suggest secukinumab (an anti-IL-17A agent) may improve cutaneous manifestations in psoriasis-SLE overlap patients.

Vunakizumab, a humanized anti-IL-17A monoclonal antibody (IgG1/κ) with a unique epitope-binding profile, selectively inhibits IL-17A-mediated inflammatory signaling. Its established safety profile and infrequent dosing regimen in IL-17-mediated diseases (e.g., psoriasis, psoriatic arthritis) warrant investigation in SLE. The investigators aim to provide new treatment options for SLE patients

Inclusion Criteria:

1. Patients aged 18-65 years meeting the 2019 EULAR/ACR classification criteria for SLE.
2. SLEDAI score was within 2-12 scores (with clinical SLEDAI [cSLEDAI] ≠ 0).
3. Occurence of new or recurrent mucocutaneous or joint involvement.
4. Stable standard treatment regimen prior to study entry but not effect: Prednisone or equivalent corticosteroid dose ≤ 20 mg per day for more than 4 weeks; Immunosuppressant less than 1 type for more than 12 weeks, including methotrexate ≤15 mg per week, azathioprine ≤100mg per day, mycophenolate mofetil ≤1.5 g per day, tacrolimus ≤2 mg per day, cyclosporine ≤150 mg per day). Antimalarials was permitted.
5. Body mass index (BMI) 18-35 kg/m² at screening.
6. Clinically eligible for Vunakizumab combination therapy with corticosteroids after investigator assessment.
7. Willing to provide written informed consent with demonstrated compliance.

Exclusion Criteria:

1. SLE with major organ dysfunction including Encephalopathy/cognitive impairment, Renal insufficiency, Cardiac insufficiency (NYHA class III-IV), Pulmonary hypertension/interstitial lung disease
2. Active SLE-related organ involvement: Lupus cerebritis, Active lupus nephritis (proteinuria ≥1g/24h), Myocardial involvement, Gastrointestinal vasculitis, Diffuse alveolar hemorrhage, Thrombocytopenic purpura, Hemophagocytic syndrome, Retinopathy
3. Concurrent autoimmune diseases affecting efficacy assessment (e.g., rheumatoid arthritis, ankylosing spondylitis, psoriatic arthritis).
4. Liver dysfunction: ALT/AST >1.5×ULN or total bilirubin >1×ULN.
5. Active malignancy within 5 years or history of malignancy.
6. Comorbidities requiring corticosteroids (e.g., asthma, Crohn's disease).
7. Active infections requiring treatment:Tuberculosis, HBV/HCV/HIV/CMV infections
8. Major surgery within 3 months prior to screening.
9. Hypersensitivity or intolerance to funakizumab.
10. Pregnancy, lactation, or planned pregnancy.
11. Biologic therapy within 3 months (anti-CD20 agents, belimumab, TNF-α inhibitors).
12. Recent intensive therapies: Systemic corticosteroids within 3 months/ Plasmapheresis/IVIG/cyclophosphamide within 3 months
13. Any condition deemed by investigators to compromise study completion or patient safety.