Abstract
Objective
To conduct a longโterm, prospective, randomized controlled trial evaluating rituximab (RTX) therapy for severe mixed cryoglobulinemia or cryoglobulinemic vasculitis (CV).
Methods
Fiftyโnine patients with CV and related skin ulcers, active glomerulonephritis, or refractory peripheral neuropathy were enrolled. In CV patients who also had hepatitis C virus (HCV) infection, treatment of the HCV infection with antiviral agents had previously failed or was not indicated. Patients were randomized to the nonโRTX group (to receive conventional treatment, consisting of 1 of the following 3: glucocorticoids; azathioprine or cyclophosphamide; or plasmapheresis) or the RTX group (to receive 2 infusions of 1 gm each, with a lowering of the glucocorticoid dosage when possible, and with a second course of RTX at relapse). Patients in the nonโRTX group who did not respond to treatment could be switched to the RTX group. Study duration was 24 months.
Results
Survival of treatment at 12 months (i.e., the proportion of patients who continued taking their initial therapy), the primary end point, was statistically higher in the RTX group (64.3% versus 3.5% [P < 0.0001]), as well as at 3 months (92.9% versus 13.8% [P < 0.0001]), 6 months (71.4% versus 3.5% [P < 0.0001]), and 24 months (60.7% versus 3.5% [P < 0.0001]). The Birmingham Vasculitis Activity Score decreased only after treatment with RTX (from a mean ยฑ SD of 11.9 ยฑ 5.4 at baseline to 7.1 ยฑ 5.7 at month 2; P < 0.001) up to month 24 (4.4 ยฑ 4.6; P < 0.0001). RTX appeared to be superior therapy for all 3 target organ manifestations, and it was as effective as conventional therapy. The median duration of response to RTX was 18 months. Overall, RTX treatment was well tolerated.
Conclusion
RTX monotherapy represents a very good option for severe CV and can be maintained over the long term in most patients.