Safety and efficacy of rituximab in nonviral cryoglobulinemia vasculitis: data from the French Autoimmunity and Rituximab registry.

Abstract

Management of nonviral cryoglobulinemia vasculitis has yet to be defined. Rituximab has emerged as a novel and promising therapeutic alternative, but data are scarce. Our objective was to evaluate the safety and efficacy of rituximab in nonviral cryoglobulinemia vasculitis in off-trial real-life patients. Prospective data from the French AutoImmunity and Rituximab (AIR) registry, which includes data on patients with autoimmune disorders treated with rituximab in off-label conditions, were analyzed. Twenty-three patients received treatment with rituximab for cryoglobulinemia vasculitis. Tolerance was marked by the occurrence of side effects in almost half of the patients, including severe infections in 6 (26%) of 23, with a rate of 14.1 per 100 patient-years. These infections occurred in a particular subset of patients ages>70 years, with essential type II mixed cryoglobulinemia and renal failure with a glomerular filtration rate of <60 ml/minute, and receiving high-dose corticosteroids. Three of these patients died. In contrast, clinical and immunologic efficacy was noted in all evaluable patients. Clinical relapses occurred in half of the patients after a median time of 13.5 months following rituximab administration, and were more frequent in patients refractory to previous immunosuppressive therapy than in previously untreated patients. Data from the AIR registry show a dramatic efficacy and a steroid-sparing effect of rituximab, but also show the occurrence of severe infections in elderly patients with renal failure and high-dose steroids. The role of rituximab in nonviral cryoglobulinemia vasculitis remains to be defined in well-designed randomized controlled trials.