Rituximab (RTX) is an effective remission-induction and maintenance treatment for patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). The major challenge of patient care is the early detection of relapse to prevent organ damage and improve survival in these individuals. A recently published single-center cohort study assessed serial ANCA, CD19+ B-cell status and relapse rate in 110 ANCA-positive AAV patients treated with RTX. Overall, the absence of proteinase 3 (PR3)- or myeloperoxidase- ANCA positivity was highly predictive for remaining relapse-free. ANCA- and B-cell monitoring could guide therapeutic decision-making to prevent relapses in AAV patients treated with RTX.