Avacopan vs Reduced-dose Glucocorticoids in ANCA-associated Vasculitis

Anti-neutrophil cytoplasm antibody (ANCA)-associated vasculitis is characterized by a small to medium-size vasculitis and the presence of ANCA. ANCA-associated vasculitis includes microscopic polyangiitis, granulomatosis with polyangiitis and eosinophilic granulomatosis with polyangiitis. ANCA-associated vasculitis can be a life-threatening disease and the mortality is 80% at 1 year in untreated patients. In 2010s, standard therapies for remission induction of ANCA-associated vasculitis were the combination of high-dose glucocorticoids and either cyclophosphamide or rituximab. Although those therapies have high remission rates of 80-90%, mortality at 5 years is still high at 10-20% mainly due to treatments-related adverse events.

In the LoVAS trial (2021, JAMA), the combination of reduced-dose glucocorticoid and rituximab showed non-inferiority to high-dose glucocorticoid and rituximab in remission rates at 6 months. In addition, adverse events were dramatically less in the reduced-dose group than in the high-dose group.

In the ADVOCATE trial (2021, NEJM), the combination of avacopan, newly developed complement C5a inhibitor, and rituximab or cyclophosphamide showed non-inferiority to high-dose glucocorticoid and rituximab or cyclophosphamide in remission rates at 6 months. The avacopan group was allowed to use glucocorticoid within 1 month from the trial entry, and over 80% of patients used glucocorticoid indeed. Regarding adverse events, they were less in the avacopan group than in the glucocorticoid group.

Although both the reduced-dose glucocorticoid regimen in the LoVAS trial and the avacopan regimen in the ADVOCATE trial are effective and safe for patients with ANCA-associated vasculitis, there is no trial directly comparing both regimens at the moment. Thus, in this multicenter, open-label, randomized, non-ineriority, phase 4 trial, the investigators aim to investigate if the combination of avacoapn, short-term (4 weeks) reduced-dose glucocorticoid and rituximab is non-inferior to the combination of reduced-dose glucocorticoid (20 weeks) and rituximab. The investigators also compare safety profiles and disease relapse between the two groups. A total of 160 patients with new-onset ANCA-associated vasculitis (microscopic polyangiitis and granulomatosis with polyangiitis) will be recruited and randomized to the two treatments groups. The primary end point is remission rate at 26 weeks, and the patients will be followed until 104 weeks for assessing disease relapse and long-term safety.