An overview of pharmacotherapy for anti-neutrophil cytoplasmic antibody-associated vasculitis

A number of recently published prospective clinical trials have enabled the definition of the type, duration and intensity of immunosuppressive treatment in anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). Patients with early or localized nonrenal disease should receive an induction therapy consisting of oral prednisone in combination with oral or parenteral methotrexate. Patients with generalized or severe disease, including those with renal vasculitis, should receive 6-10 pulses of cyclophosphamide over 3-6 months or 3-6 months of daily oral cyclophosphamide plus tailing doses of prednisone. Remission therapy consists of azathioprine plus low-dose prednisone given for at least 18-24 months after the achievement of remission. Despite their efficacy, treatment with conventional agents is associated with a number of problems, including a high number of relapses and considerable morbidity. To overcome these issues, research has focused on novel immunosuppressive drugs, such as mycophenolate mofetil and leflunomide, and on molecular targeted therapy. B-cell depletion with rituximab has been shown to be at least as effective as cyclophosphamide in inducing remission in AAV, but it is not safer. TNF-α blockade with infliximab is a promising strategy for refractory disease, but evidence from controlled trials is still lacking. With increased understanding of the disease, novel agents and therapy principles are rapidly emerging and undergoing clinical testing.