Discontinuation of MMF in ANCA Vasculitis Receiving Rituximab

Guideline-Based Maintenance Therapy Recommendations

The American College of Rheumatology recommends rituximab as a first-line maintenance agent following successful remission induction with either cyclophosphamide or rituximab 1, 2
The American College of Rheumatology conditionally recommends methotrexate or azathioprine over MMF for maintenance therapy, as azathioprine demonstrated superior efficacy with lower relapse rates compared to MMF in head-to-head trials 2, 3
The American College of Rheumatology explicitly positions MMF as a less preferred option, reserved only for patients who cannot tolerate or have contraindications to rituximab, methotrexate, or azathioprine 2, 3

No guideline recommends combining rituximab with MMF for maintenance therapy - all recommendations present these as alternative monotherapy options (plus low-dose glucocorticoids) 1, 2
The Kidney Disease Outcomes Quality Initiative commentary emphasizes that maintenance therapy consists of "either rituximab or azathioprine" with low-dose glucocorticoids, not combination immunosuppression 1
When rituximab is used for maintenance, scheduled re-dosing protocols (typically 500-1000 mg every 6 months) are recommended without additional immunosuppressive agents 2, 3

If plasma exchange is being used concurrently, hold plasma exchange for 48-72 hours after rituximab infusion to avoid removing the antibody 1
MMF can be discontinued at the time of rituximab initiation for maintenance therapy, as there is no transition period requiring overlap 2
Continue low-dose glucocorticoids during the transition, as these are part of the standard maintenance regimen with rituximab 1

Monitor serum immunoglobulins every 6 months during rituximab therapy 1
Continue Pneumocystis jirovecii pneumonia (PJP) prophylaxis with trimethoprim/sulfamethoxazole throughout rituximab maintenance 1
Use scheduled rituximab re-dosing rather than ANCA titers or CD19+ B cell counts to guide timing, as flares can occur despite B-cell depletion or negative ANCA 2, 3