Moderator's view: Should all patients with ANCA-associated vasculitis be primarily treated with rituximab?

Experience with rituximab in patients with new ANCA-associated vasculitis (AAV) is still very limited, especially in patients with severe (organ- or life-threatening) AAV. Rituximab may be more effective in anti-PR3 AAV, but potentially less effective in some granulomatous manifestations of AAV. We do not know what the response is to rituximab on the tissue level. Rituximab induction needs to be followed by maintenance treatment, and potentially very long rituximab maintenance may result in higher risk of rituximab-related complications (e.g. decrease in IgG levels). Long-term experience with rituximab in AAV is insufficient. Treatment with rituximab is more expensive than the standard treatment with cyclophosphamide and corticosteroids and seems to be cost-effective only in patients primarily treated with cyclophosphamide. Rituximab can be used in some newly diagnosed patients with AAV (e.g. women with child-bearing potential, or patients with active vasculitis and severe infection), but with the available information, it may be too early to use it as a first-line treatment in all new AAV patients.