The main objective of this study is to explore the efficacy of avacopan in participants affected by AAV.
Male and female children and adolescents from 6 to < 18 years old of age.
Clinical diagnosis of Granulomatosis with Polyangiitis (GPA) or microscopic polyangiitis (MPA), consistent with Chapel-Hill Consensus Conference definitions (Jennette et al, 2013).
Positive anti-PR3(Anti-Proteinase 3) or anti-MPO(Anti-Myeloperoxidase) antibody documented at Screening or historically. Historical positivity is acceptable (even if Screening is negative) if supported by verifiable lab source documentation obtained during AAV diagnosis or disease course; use the most recent positive result.
At least 1 PVAS major item, at least 3 PVAS nonmajor items, or atleast the 2 renal items of proteinuria and hematuria.
Any other known multisystem autoimmune disease including and not limited to eosinophilic granulomatosis with polyangiitis (EGPA, previously, Churg-Strauss disease), systemic lupus erythematosus, IgA vasculitis / Henoch-Schönlein, Purpura, rheumatoid vasculitis, Sjögren's syndrome, anti-glomerular basement membrane disease, or cryoglobulinemic vasculitis.
Renal replacement therapy / plasmapheresis: subjects will be excluded who received, require, or initiate CRRT (continuous renal replacement therapy), hemodialysis, any renal dialysis, or plasmapheresis within 14 days prior to Screening or between Screening and Day 1.
History of kidney transplantation or is anticipated to require renal transplantation during the study.
Alveolar hemorrhage requiring invasive pulmonary ventilation support anticipated to last beyond the screening period of the study.
Single group
Avacopan
DrugOral administration
Proportion of Participants Achieving Disease Remission at Week 26 According to the Pediatric Vasculitis Activities Score (PVAS)
Proportion of Participants With Sustained Disease Remission at Week 52 According to the PVAS
Plasma Concentrations of Avacopan
Number of Participants Experiencing Treatment-emergent Adverse Events (TEAE)
TEAEs are any event that occurred after the participant received study treatment. Any clinically significant changes in vital signs, electrocardiograms, and clinical laboratory tests that occurred after study treatment administration were recorded as TEAEs. A serious TEAE is any untoward medical occurrence in a clinical study participant after first dose irrespective of a causal relationship with the study treatment(s) that resulted in death, was immediately life threatening, required in-patient hospitalization or prolongation of existing hospitalization, resulted in persistent or significant disability/incapacity, a congenital anomaly/birth defect, or another medically important serious event.
Proportion of Participants Achieving Disease Remission at Week 26 According to the Birmingham Vasculitis Activity Score (BVAS)
Proportion of Participants Achieving Disease Remission at Week 52 According to the BVAS
