BDB-001 Phase III Trial in ANCA-Associated Vasculitis

Inclusion Criteria: 1. 18 years old≤Age≤75 years old, male or female; 2. Diagnosis of granulomatosis with polyangiitis(GPA) or microscopic polyangiitis(MPA)； 3. Newly diagnosed or relapsed GPA or MPA that requires treatment with a full starting dose of prednisone plus cyclophosphamide/azathioprine or rituximab； 4. Positive test for anti-proteinase 3(PR3) or anti-myeloperoxidase (MPO)； 5. Estimated glomerular filtration rate ≥15 mL/minute/1.73 m\^2； 6. At least 1 major item, or at least 3 non-major items, or at least the 2 renal items on BVAS； Exclusion Criteria: 1. Active tuberculosis infection; 2. alveolar hemorrhage requiring pulmonary ventilation support； 3. History of any malignancy of any organ system within 5 years prior to the first dose, except for basal cell carcinoma of the skin or carcinoma in situ (e.g., cervical or breast carcinoma in situ) that has been completely resected and shows no evidence of local recurrence or metastasis. 4. Any other known multi-system autoimmune disease including eosinophilic granulomatosis with polyangiitis (Churg-Strauss), systemic lupus erythematosus, IgA vasculitis (Henoch-Schönlein), rheumatoid vasculitis,anti-glomerular basement membrane disease, or cryoglobulinemic vasculitis； 5. HBsAg positive,or HBcAb positive and HBV-DNA positive； 6. Received CYC within 3 months before the first administration or Received rituximab(RTX) or other B-cell antibody within 12 months before the first administration； 7. Received glucocorticoid shock therapy within 4 weeks before the first administration； 8. Received an oral daily dose of a GC of \> 10 mg prednisone-equivalent for more than 6 weeks continuously before the first administration； 9. Received a anti-tumor necrosis factor and other biological agents treatment within 12 weeks before the first administration； 10. Received Continuous dialysis treatment for 12 weeks or more before the first administration; Received Dialysis within 1 week before the first administration; 11. Received intravenous immunoglobulin (Ig) or plasma exchange within 4 weeks before the first administration; 12. Pregnant or lactating.