2021 American College of Rheumatology/Vasculitis Foundation Guideline for the Management of Antineutrophil Cytoplasmic Antibody–Associated Vasculitis (Part 9)

Let us continue with our discussion of the guidelines of the American College of Rheumatology (ACR) in relation to the  antineutrophil cytoplasmicantibody (ANCA)–associated vasculitides (AAV).
Let me emphasize that ANCA-AAV is a group of diseases composed of granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA).
For patients with GPA/MPA who are getting rituximab for remission maintenance, it is conditionally recommended for a scheduled re-dosing over using ANCA titers to guide in re-dosing.
It has been known that patients who received rituximab for remission maintenance based on ANCA titers had similar rates of relapse as those getting rituximab as a scheduled dose.
However, this study  is limited. 
It is recognized that flares can occur when patients’ test results for ANCA are negative.
Moreover, the patients with severe GPA/MPA whose disease has entered remission it is best to use methotrexate or azathioprine over mycophenolate mofetil for remission maintenance.
Methotrexate and azathioprine are  effective in remission maintenance. Azathioprine is favored over mycophenolate mofetil.
Mycophenolate mofetil can be considered for those unable to tolerate or with contraindications to methotrexate, azathioprine, or rituximab.
We will provide more insights on the medications worthy of consideration for remission maintenance of AAV-ANCA.