Untreated, Granulomatosis with polyangiitis is rapidly fatal, with a median survival of 5 months, and more than 90% of patients are dead within 2 years of diagnosis.
Therapy usually involves
1. steroids
2. immune modulators: includes cyclophosphamide (Cytoxan®), methotrexate, mofetil (CellCept®)
3. antibodies: rituximab (Rituxan®) especially for disease relapse. Belimumab (Benlysta®) is under investigation
4. under investigation: plasma exchange, anti B- & T-cell biologics, and interleukin-5