In this study, we retrospectively evaluated the clinical and immunological effects of RTX treatment in patients with treatment refractory or relapsing ANCA-positive vasculitis. The decision to prefer RTX treatment was made in cyclophosphamide-resistant patients; thus, they were heavily treated. We observed in our overall

patient cohort a significant decrease in disease activity, with 21% of patients achieving complete remission and 41% displaying good treatment response as indicated with ≥50% decrease in BVAS score at 6 months. Good treatment effect was seen in patients with renal involvement, with 64% of patients being in remission at 6 months after RTX treatment. In addition, repeated treatment courses because of relapses also induced successful remission. To date, one CB-839 ic50 open-label, randomized, multicentre trial involving 44 patients with newly diagnosed ANCA-associated renal vasculitis treated with RTX has been published [11]. In this study cohort, RTX was used as a remission induction therapy together

with two pulses of CYC, and sustained remission at 12 months was achieved in 76% of patients with newly diagnosed ANCA-associated vasculitis. In addition, Stone et al. CAL-101 ic50 [10] reported recently in their multicentre, randomized, double-blind non-inferiority trial that RTX therapy was not inferior as compared to CYC for the induction of remission and may be superior in relapsing disease. In this study cohort, patients with severe ANCA-associated vasculitis, either newly diagnosed or with relapsing disease, were included, and Urocanase 64% in the RTX group reached remission at 6 months as compared to 52% in controls. Interestingly, RTX proved to be more efficacious than CYC, inducing remission in patients with relapsing

disease, 67% vs. 42%, respectively [10]. However, these studies did not assess the duration of remission beyond study end point and the effect of repeated RTX treatment. In our studied cohort, 50% of patients remained in sustained remission within a median follow-up time of 21 months regarding renal vasculitis. Thus, the positive additive immunosuppressive effect of RTX therapy in remission maintenance might be considered. Published evidence based mostly on case and retrospective reports regarding the effect of RTX on granulomatous orbital involvement is somewhat contradictory. Several case reports suggest a beneficial effect of anti-B cell treatment in refractory orbital granulomas [18–20]. Taylor et al. [21] recently reported beneficial effect of RTX treatment in seven patients with granulomatous orbital disease who all entered remission within 2–7 months without relapse. Of note, ocular biopsy samples from two patients obtained pre-RTX therapy showed the presence of numerous CD20+ cells in the ocular tissue, whereas these cells were undetectable post-treatment [21].