Randomized controlled trials in vasculitis associated with anti-neutrophil cytoplasmic antibodies

To review three major randomized clinical trials in forms of vasculitis associated with anti-neutrophil cytoplasmic antibodies.

The design features, results, and context of the Cyclophosphamide versus Azathioprine for the Remission Phase of Vasculitis, Non-renal AAV alternatively treated with Methotrexate, and Wegener Granulomatosis Etanercept Trial are reviewed.

Until recently, therapies for Wegener granulomatosis and microscopic polyangiitis have been based primarily on a relatively small number of nonrandomized studies. During the past 18 months, three randomized, controlled trials (one double-blinded) have been performed in vasculitis associated with anti-neutrophil cytoplasmic antibodies. Careful comparisons of the results of these trials yield insights into new standards of care for vasculitis associated with anti-neutrophil cytoplasmic antibodies. This paper summarizes the designs of these three trials; highlights their principal conclusions, strengths, and shortcomings; and distills from their results several recommendations on major questions related to the therapy of vasculitis associated with anti-neutrophil cytoplasmic antibodies.