B-cell-targeted therapy in systemic vasculitis

The present review discusses the evidence supporting the use of B-cell-targeted therapy in the treatment of various forms of systemic vasculitis with a focus on the use of rituximab (RTX), in the antineutrophil cytoplasmic autoantibody (ANCA)-associated vasculitides (AAV).

Long-term follow-up of the two studies establishing the efficacy of a RTX-based induction regimen for severe AAV have demonstrated noninferiority of a single course of RTX compared with conventional therapy for remission maintenance. In addition, these observations highlight an association between relapse and B-cell reconstitution in patients treated with RTX. The maintenance of remission using rituximab in systemic ANCA-associated vasculitis trial compared a regimen of RTX infusions every 6 months to azathioprine for remission maintenance and concluded that serial RTX lead to higher rates of sustained remission.RTX is also an established therapy for cryoglobulinemic vasculitis associated with hepatitis C viral (HCV) infection. Recently published data support the long-term efficacy and safety of RTX for cryoglobulinemic vasculitis.

B-cell depletion with RTX is an established therapy for both remission induction and maintenance in severe AAV and in HCV-related cryoglobulinemic vasculitis. There are limited data to support use of B-cell-targeted therapy in refractory cases of other forms of systemic vasculitis such as eosinophilic granulomatosis with polyangiitis and Takayasu's arteritis.