Role of Cyclophosphamide in ANCA-associated vasculitis

Carol Langford, MD (Clevelend Clinic)

Thursday 5/10/12

If you’re not careful, you could fall into a trap and think that Cyclophosphomide (CYC) has such a bad “rep” that is should not be used in ANCA-associated vasculitides (specifically GPA).  Dr. Langford gave a great talk explaining when CYC should be used.  Though CYC has a number of toxic effects, it is still considered a “go to” medication for *severe* GPA disease.  Unfortunately, we never walked away with a strict definition of what *severe* is, but presumably this would mean high creatinine, crescentic GN, and/or diffuse alveolar hemorrhage (+/- the need for mechanical ventilation).  CYC has a great track record of inducing remission, and both the IV and PO forms seem to be equally effective at achieving induction. The choice of using PO or IV forms will depend on the physician and the patient, as the former has a lower rate of relapse but the latter has a lower rate of infectious complications (though neither difference is so significant as to allow her to make a definitive recommendation of one route versus another).  However, it appears that both IV and PO forms will need to be followed by a maintenance drug, either a) methotrexate (MTX), b) azathioprine (AZA), or c) mycophenolate (MMF).  Regarding MTX versus AZA, both are equally well at maintaining remission, though some would consider using MTX if the disease is not too severe.  Unfortunately, the story isn’t the same for MMF versus AZA, where the former is less superior at maintaining remission (38% versus 55%, p 0.03).