Maintenance of remission of ANCA vasculitis by rituximab based on B cell repopulation versus serological flare: a randomised trial.

OBJECTIVE: To compare two long-term remission maintenance strategies for antineutrophil cytoplasmic antibody (ANCA) vasculitis. METHODS: We conducted a prospective, single-centre, open-label, randomised controlled trial of patients with ANCA vasculitis in remission after completing at least 2 years of fixed-schedule rituximab. In the B cell arm, rituximab was reinfused upon B cell repopulation; in the ANCA arm, rituximab was reinfused upon significant rise in ANCA level. Evaluations were conducted every 3 months. The primary endpoint was clinical relapse, defined as a modified BVAS/WG >0 by 36 months. Secondary endpoints included serious adverse events (SAEs) and rituximab exposure. RESULTS: 115 patients were enrolled. Median follow-up time was 4.1 years (IQR 2.5-5.0). By Kaplan-Meier analysis, 4.1% (95% CI 1.0 to 15.6) of patients had a clinical relapse in the B cell arm, compared with 20.5% (95% CI 11.9 to 34.1) in the ANCA arm, at 3 years after study entry (log-rank p=0.045). Total SAEs, including infectious SAEs, and deaths did not differ. The number of SAEs due to COVID-19 was higher in the B cell arm (p=0.049). In the B cell arm, patients received a mean of 3.6 (SD 2.4) infusions (3.6 g) per person over the median study follow-up time of 4.1 years, compared with 0.5 (SD 1.4) infusions (0.5 g) per patient in the ANCA arm (p<0.001). CONCLUSIONS: Rituximab dosed for B cell repopulation results in fewer clinical relapses than when dosed for a rise in ANCA level in maintenance of remission for ANCA vasculitis. Overall safety was equivalent; SAEs due to COVID-19 and rituximab exposure were higher with the B cell strategy. TRIAL REGISTRATION NUMBER: NCT02749292.

Long-term maintenance therapy using rituximab-induced continuous B-cell depletion in patients with ANCA vasculitis.

BACKGROUND AND OBJECTIVES: Remission in the majority of ANCA vasculitis patients is not sustained after a single course of rituximab, and risk of relapse warrants development of a successful strategy to ensure durable remission. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: A retrospective analysis of ANCA vasculitis patients who underwent maintenance therapy using rituximab-induced continuous B-cell depletion for up to 7 years was performed. Maintenance therapy with rituximab was initiated after achieving remission or converting from other prior maintenance therapy. Continuous B-cell depletion was achieved in all patients by scheduled rituximab administration every 4 months. Disease activity, serologic parameters, adverse events, and survival were examined. RESULTS: In the study, 172 patients (mean age=60 years, 55% women, 57% myeloperoxidase-ANCA) treated from April of 2006 to March of 2013 underwent continuous B-cell depletion with rituximab. Median remission maintenance follow-up time was 2.1 years. Complete remission (Birmingham Vasculitis Activity Score [BVAS] = 0) was achieved in all patients. Major relapse (BVAS ≥ 3) occurred in 5% of patients and was associated with weaning of other immunosuppression drugs. Remission was reinduced in all patients. Survival mirrored survival of a general age-, sex-, and ethnicity-matched United States population. CONCLUSION: This analysis provides evidence for long-term disease control using continuous B-cell depletion. This treatment strategy in ANCA vasculitis patients also seems to result in survival rates comparable with rates in a matched reference population. These findings suggest that prospective remission maintenance treatment trials using continuous B-cell depletion are warranted.

Contaminated cocaine and antineutrophil cytoplasmic antibody-associated disease.

BACKGROUND AND OBJECTIVES: Approximately 70% of illicit cocaine consumed in the United States is contaminated with levamisole. Most commonly used as a veterinary antihelminthic agent, levamisole is a known immunomodulating agent. Prolonged use in humans has been associated with cutaneous vasculitis and agranulocytosis. We describe the development of a systemic autoimmune disease associated with antineutrophil cytoplasmic antibodies (ANCA) in cocaine users. This complication appears to be linked to combined cocaine and levamisole exposure. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Cases were identified between March 2009 and November 2010 at Massachusetts General Hospital's ANCA laboratory. Cocaine exposure was identified from patient history in all cases. Medical records were reviewed for clinical presentation and for laboratory and diagnostic evaluation. RESULTS: Thirty cases of ANCA positivity associated with cocaine ingestion were identified. All had antimyeloperoxidase antibodies and 50% also had antiproteinase 3 antibodies. Complete clinical and laboratory data were available for 18 patients. Arthralgia (83%) and skin lesions (61%) were the most frequent complaints at presentation. Seventy-two percent of patients reported constitutional symptoms, including fever, night sweats, weight loss, or malaise. Four patients had biopsy-proven vasculitis. Two cases of acute kidney injury and three cases of pulmonary hemorrhage occurred. From the entire cohort of 30, two cases were identified during the first 3 months of our study period and nine cases presented during the last 3 months. CONCLUSIONS: We describe an association between the ingestion of levamisole-contaminated cocaine and ANCA-associated systemic autoimmune disease. Our data suggest that this is a potentially life-threatening complication of cocaine use.

Rituximab as maintenance therapy for anti-neutrophil cytoplasmic antibody-associated vasculitis.

BACKGROUND AND OBJECTIVES: Ongoing randomized trials seek to validate the efficacy of rituximab as an induction agent for anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV). However, no studies directly address the role of rituximab as maintenance therapy. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: This retrospective study reports the authors' experience with continuous rituximab administration in 39 patients in complete or partial remission at the time of rituximab initiation. All 39 patients had at least 1 year of follow-up, and 20 had 2 years of follow-up. RESULTS: Disease activity, as measured by a modified Birmingham Vasculitis Activity Score, decreased from a median of 1 at baseline to 0 at 12 (P < 0.001) and 24 months (P = 0.02). Three patients experienced nonorgan-threatening flares during 708 patient-months of follow-up. Each flare occurred after at least 20 months of follow-up. The percentage of patients on cytotoxic immunosuppression decreased from 87% at baseline to 41% at 12 months (P < 0.001) and 30% at 24 months (P = 0.002). The percentage of patients on prednisone decreased from 92% at baseline to 59% at 12 months (P < 0.001) and 55% at 24 months (P = 0.02). Two patients developed late-onset neutropenia; both responded to treatment with recombinant granulocyte colony-stimulating factor. CONCLUSIONS: The successful use of continuous anti-B cell therapy in patients with AAV in complete or partial remission is reported. This extends the potential role of rituximab beyond induction to include maintenance therapy. However, more data are required regarding the delayed adverse effects of rituximab.