Rituximab Plus Avacopan increases remission rates in ANCA-associated vasculitis

Patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) treated with rituximab (RTX) showed a significantly higher remission rate, which was maintained at week 52, in patients in the avacopan group compared to patients in the prednisone cohort.

Patients in the avacopan cohort also showed numerical improvements in remission at week 26, albuminuria, relapse rate, estimated glomerular filtration rate (eGFR), and less glucocorticoid toxicity, according to the study “Efficacy and Safety of Avacopan in Patients with ANCA-Associated Vasculitis”. Receive Rituximab in a Phase 3 trial,” presented at the 2023 Convergence of the American College of Rheumatology in San Diego, California.¹

In the randomized, double-blind, double-dummy, controlled phase 3 ADVOCATE trial, investigators evaluated whether avacopan, an oral selective C5a receptor inhibitor, could replace a glucocorticoid-tapering regimen. Patients were categorized by ANCA status (either anti-proteinase 3 [PR3] positive or anti-myeloperoxidase positive), vasculitis disease status (recurrent or newly diagnosed), and immunosuppressive treatment (cyclophosphamide). [CYC] or RTX).

“The American College of Rheumatology (ACR)/Vasculitis Foundation guidelines recommend induction treatment with RTX over cyclophosphamide (CYC),” wrote principal investigator Anisha Dua, MD, MPH, associate professor at Northwestern University. , and colleagues. “For relapsing disease, the European Alliance of Societies for Rheumatology (EULAR) recommends RTX.”

The co-primary efficacy endpoints were the proportion of patients who could achieve remission at week 26 and those who could achieve a sustained remission at week 52. Remission was defined as a Birmingham Vasculitis Activity Score. [BVAS] of 0 and no glucocorticoid use for AAV 4 weeks prior to measurement.

Patients were given intravenous RTX 375 mg/m2 once a week for 4 weeks from the first day of the study. Repeated doses of RTX were not included, for the labeled regimen approved at the beginning of the trial.

In total, 330 patients were included in the study, of which 214 (64.8%) were in the RTX layer. The average age of the patients was 60 years, 76% of the patients had renal vasculitis according to the BVAS score, 46% were PR3-ANCA positive, and 58% had diagnosed AAV. More (57%) patients in the avacopan cohort were men compared with 48.6% in the prednisone group. The eGFR at baseline in the avacopan and prednisone groups was 57.1±32.2 and 56.0±33.4 mL/min/1.73 m2, respectively.

At the 26-week mark, 77.6% (n = 83) of patients in the avacopan group and 75.7% (n = 81) of patients in the prednisone group achieved remission. However, sustained remission was achieved in 71.0% (n = 76) of patients receiving avacopan and 56.1% (n = 60) of those treated with prednisone at week 52.

Treatment-emergent serious adverse events (TEAEs) were observed in 34.6% (n = 37, 62 total events) of those in the avacopan cohort compared with 39.3% (n = 42, 91 total events) in the prednisone group. The relapse rate was lower in those treated with avacopan (8.7%, n = 9) compared to prednisone (20.2%, n = 21). Improvements were also observed in glucocorticoid-associated toxicity and albuminuria for patients in the avacopan cohort.

“These results demonstrate the effectiveness of avacopan in achieving and sustaining remission in patients with AAV treated with RTX”, concluded the researcher.

Reference

1. ^{Duvuru G, Dua A, Yue H, Salvarani C, et al. Efficacy and Safety of Avacopan in Patients with ANCA-Associated Vasculitis Receiving Rituximab in a Phase 3 Trial. Presented at: American College of Rheumatology Convergence 2023. San Diego, CA. November 10-15, 2023.}