Predicting relapse and infection to optimize patient outcomes in ANCA-associated vasculitis: data from the MAINRITSAN trials cohort

Why clinicians should know about it

• Picked for Rheumatology (paper of the day, 2 October 2026): Relapse and infection prediction models in ANCA-associated vasculitis

Abstract

OBJECTIVES: Long-term follow-up of the MAINRITSAN trials confirmed the efficacy of rituximab (RTX) in preventing relapses in ANCA-associated vasculitis (AAV). Extending RTX maintenance beyond 18 months may benefit high-risk patients. The aim of this study was to validate relapse and infection prediction models to guide individualized RTX extension decisions. METHODS: Data from 217 patients in the MAINRITSAN1 and MAINRITSAN2 trials treated with RTX for 18 months with follow-up through December 2020 were analyzed. We externally validated relapse and infection prediction models from McClure et al. Primary endpoints were relapse-free survival and serious infection-free survival. RESULTS: Relapse occurred in 76 patients, with a 72-month relapse-free survival rate of 55% (95% CI 48-64). Serious infections occurred in 33 patients, with a cumulative 72-month incidence of 20%. The relapse model (factors: male sex, age > 60 years, ANCA positivity, relapsing disease, ENT involvement, prednisone dose) predicted major relapse (coefficient 1.34, p = 0.04) and identified high-risk patients with shorter major relapse-free survival (HR 1.91, 95% CI 0.97-3.76, p = 0.059). The relapse score was associated with major relapse risk predominantly within the PR3-ANCA subgroup (coefficient 2.76, p = 0.01). The infection model (factors: male sex, structural lung disease, diabetes, occurrence of infections during maintenance therapy, and gammaglobulin level) identified high-risk patients with shorter serious infection-free survival (HR 2.93, 95% CI 1.28-6.72, p = 0.011). CONCLUSION: The relapse prediction model demonstrated reproducible performance in this external validation cohort and may contribute to clinically relevant risk stratification, especially in PR3-ANCA patients. The infection model showed stronger predictive performance and may support individualized discussions regarding RTX extension.

Abstract as published, via PubMed.