John H. Stone

BACKGROUND: Cyclophosphamide and glucocorticoids have been the cornerstone of remission-induction therapy for severe antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis for 40 years. Uncontrolled studies suggest that rituximab is effective and may be safer than a cyclophosphamide-based regimen. METHODS: We conducted a multicenter, randomized, double-blind, double-dummy, noninferiority trial of rituximab (375 mg per square meter of body-surface area per week for 4 weeks) as compared with cyclophosphamide (2 mg per kilogram of body weight per day) for remission induction. Glucocorticoids were tapered off; the primary end point was remission of disease without the use of prednisone at 6 months. RESULTS: Nine centers enrolled 197 ANCA-positive patients with either Wegener's granulomatosis or microscopic polyangiitis. Baseline disease activity, organ involvement, and the proportion of patients with relapsing disease were similar in the two treatment groups. Sixty-three patients in the rituximab group (64%) reached the primary end point, as compared with 52 patients in the control group (53%), a result that met the criterion for noninferiority (P<0.001). The rituximab-based regimen was more efficacious than the cyclophosphamide-based regimen for inducing remission of relapsing disease; 34 of 51 patients in the rituximab group (67%) as compared with 21 of 50 patients in the control group (42%) reached the primary end point (P=0.01). Rituximab was also as effective as cyclophosphamide in the treatment of patients with major renal disease or alveolar hemorrhage. There were no significant differences between the treatment groups with respect to rates of adverse events. CONCLUSIONS: Rituximab therapy was not inferior to daily cyclophosphamide treatment for induction of remission in severe ANCA-associated vasculitis and may be superior in relapsing disease. (Funded by the National Institutes of Allergy and Infectious Diseases, Genentech, and Biogen; ClinicalTrials.gov number, NCT00104299.)

BACKGROUND: The 18-month efficacy of a single course of rituximab as compared with conventional immunosuppression with cyclophosphamide followed by azathioprine in patients with severe (organ-threatening) antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis is unknown. METHODS: In a multicenter, randomized, double-blind, double-dummy, noninferiority trial, we compared rituximab (375 mg per square meter of body-surface area administered once a week for 4 weeks) followed by placebo with cyclophosphamide administered for 3 to 6 months followed by azathioprine for 12 to 15 months. The primary outcome measure was complete remission of disease by 6 months, with the remission maintained through 18 months. RESULTS: A total of 197 patients were enrolled. As reported previously, 64% of the patients in the rituximab group, as compared with 53% of the patients in the cyclophosphamide-azathioprine group, had a complete remission by 6 months. At 12 and 18 months, 48% and 39%, respectively, of the patients in the rituximab group had maintained the complete remissions, as compared with 39% and 33%, respectively, in the comparison group. Rituximab met the prespecified criteria for noninferiority (P<0.001, with a noninferiority margin of 20%). There was no significant difference between the groups in any efficacy measure, including the duration of complete remission and the frequency or severity of relapses. Among the 101 patients who had relapsing disease at baseline, rituximab was superior to conventional immunosuppression at 6 months (P=0.01) and at 12 months (P=0.009) but not at 18 months (P=0.06), at which time most patients in the rituximab group had reconstituted B cells. There was no significant between-group difference in adverse events. CONCLUSIONS: In patients with severe ANCA-associated vasculitis, a single course of rituximab was as effective as continuous conventional immunosuppressive therapy for the induction and maintenance of remissions over the course of 18 months. (Funded by the National Institute of Allergy and Infectious Diseases and others; RAVE ClinicalTrials.gov number, NCT00104299.)

OBJECTIVE: To refine and validate the Birmingham Vasculitis Activity Score (BVAS) as a disease-specific activity index for Wegener's granulomatosis (WG). METHODS: Sixteen members of the International Network for the Study of the Systemic Vasculitides (INSSYS) revised the BVAS, with 3 goals: to reduce the redundancy of some component items, to enhance its ability to capture important disease manifestations specific to WG, and to streamline the instrument for use in clinical research. We defined the items and weighted them empirically as either minor (e.g., nasal crusting = 1 point) or major (e.g., alveolar hemorrhage = 3 points). We then validated the new, disease-specific BVAS/WG in 2 simulation exercises and a clinical case series that involved 117 patients with WG. RESULTS: We removed 38 items from the original BVAS, revised 9 items, and added 7 new items. Correlations between the scores on the BVAS/WG and the physician's global assessment (PGA) of disease activity were high, even when patients in remission were excluded. In the clinical case series, Spearman's rank correlation coefficient between the BVAS/WG and the PGA was r = 0.81 (95% confidence interval 0.73-0.87). The interobserver reliability using intraclass (within-case) correlation coefficients in the 2 simulation exercises was r = 0.93 for the BVAS/WG and r = 0.88 for the PGA in the first and r = 0.91 for the BVAS/WG and r = 0.88 for the PGA in the second. There was no significant observer effect in the scoring of the BVAS/WG or the PGA. The discriminant validity of the BVAS/WG was good: r = 0.73 (95% confidence interval 0.43-0.83). CONCLUSION: The BVAS/WG is a valid, disease-specific activity index for WG. Tested in simulation exercises and in actual patients, the BVAS/WG correlates well with the PGA, is sensitive to change, and has good inter- and intraobserver reliability. The INSSYS will use the BVAS/WG to assess the primary outcome in a phase II/III trial of etanercept in WG.

OBJECTIVE: To assess the clinical effects of rituximab therapy in patients with antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). METHODS: The study group comprised 11 patients who had active AAV despite receiving maximally tolerated doses of cyclophosphamide or had contraindications for cyclophosphamide use. All patients had ANCA reactive against proteinase 3. The patients received rituximab infusions and glucocorticoids to induce remission. Three patients also received plasma exchange. No other immunosuppressive agents were used. Glucocorticoids were tapered as soon as control of disease activity was achieved. Disease activity was monitored using the Birmingham Vasculitis Activity Score, modified for Wegener's granulomatosis. RESULTS: Rituximab therapy was well tolerated by all patients, and adverse events were rare. Following the rituximab infusions, circulating B lymphocytes became undetectable, and ANCA titers decreased significantly. Remission was achieved in all patients and was maintained while B lymphocytes were absent. CONCLUSION: The ability to achieve stable remissions with rituximab in patients with AAV refractory to conventional therapy suggests that B lymphocyte depletion may be a safe, effective, mechanism-based treatment modality for treatment of patients with these conditions.