Merkel, Peter A.

Objective To provide evidence‐based recommendations and expert guidance for the management of antineutrophil cytoplasmic antibody–associated vasculitis (AAV), including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Methods Clinical questions regarding the treatment and management of AAV were developed in the population, intervention, comparator, and outcome (PICO) format (47 for GPA/MPA, 34 for EGPA). Systematic literature reviews were conducted for each PICO question. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence and formulate recommendations. Each recommendation required ≥70% consensus among the Voting Panel. Results We present 26 recommendations and 5 ungraded position statements for GPA/MPA, and 15 recommendations and 5 ungraded position statements for EGPA. This guideline provides recommendations for remission induction and maintenance therapy as well as adjunctive treatment strategies in GPA, MPA, and EGPA. These recommendations include the use of rituximab for remission induction and maintenance in severe GPA and MPA and the use of mepolizumab in nonsevere EGPA. All recommendations are conditional due in part to the lack of multiple randomized controlled trials and/or low‐quality evidence supporting the recommendations. Conclusion This guideline presents the first recommendations endorsed by the American College of Rheumatology and the Vasculitis Foundation for the management of AAV and provides guidance to health care professionals on how to treat these diseases.

Objective To provide evidence‐based recommendations and expert guidance for the management of giant cell arteritis (GCA) and Takayasu arteritis (TAK) as exemplars of large vessel vasculitis. Methods Clinical questions regarding diagnostic testing, treatment, and management were developed in the population, intervention, comparator, and outcome (PICO) format for GCA and TAK (27 for GCA, 27 for TAK). Systematic literature reviews were conducted for each PICO question. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to rate the quality of the evidence. Recommendations were developed by the Voting Panel, comprising adult and pediatric rheumatologists and patients. Each recommendation required ≥70% consensus among the Voting Panel. Results We present 22 recommendations and 2 ungraded position statements for GCA, and 20 recommendations and 1 ungraded position statement for TAK. These recommendations and statements address clinical questions relating to the use of diagnostic testing, including imaging, treatments, and surgical interventions in GCA and TAK. Recommendations for GCA include support for the use of glucocorticoid‐sparing immunosuppressive agents and the use of imaging to identify large vessel involvement. Recommendations for TAK include the use of nonglucocorticoid immunosuppressive agents with glucocorticoids as initial therapy. There were only 2 strong recommendations; the remaining recommendations were conditional due to the low quality of evidence available for most PICO questions. Conclusion These recommendations provide guidance regarding the evaluation and management of patients with GCA and TAK, including diagnostic strategies, use of pharmacologic agents, and surgical interventions.

Objective To provide evidence‐based recommendations and expert guidance for the management of antineutrophil cytoplasmic antibody–associated vasculitis (AAV), including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). Methods Clinical questions regarding the treatment and management of AAV were developed in the population, intervention, comparator, and outcome (PICO) format (47 for GPA/MPA, 34 for EGPA). Systematic literature reviews were conducted for each PICO question. The Grading of Recommendations Assessment, Development and Evaluation methodology was used to assess the quality of evidence and formulate recommendations. Each recommendation required ≥70% consensus among the Voting Panel. Results We present 26 recommendations and 5 ungraded position statements for GPA/MPA, and 15 recommendations and 5 ungraded position statements for EGPA. This guideline provides recommendations for remission induction and maintenance therapy as well as adjunctive treatment strategies in GPA, MPA, and EGPA. These recommendations include the use of rituximab for remission induction and maintenance in severe GPA and MPA and the use of mepolizumab in nonsevere EGPA. All recommendations are conditional due in part to the lack of multiple randomized controlled trials and/or low‐quality evidence supporting the recommendations. Conclusion This guideline presents the first recommendations endorsed by the American College of Rheumatology and the Vasculitis Foundation for the management of AAV and provides guidance to health care professionals on how to treat these diseases.

ObjectiveTo describe clinical manifestations and outcomes in patients with eosinophilic granulomatosis with polyangiitis (EGPA) in North America.MethodsAnalysis of patients aged 18 years or older who fulfilled the 1990 American College of Rheumatology Classification Criteria for EGPA enrolled in the Vasculitis Clinical Research Consortium from 2003 to 2019. Main clinical characteristics, treatments, outcomes, and accumulated damage were studied.ResultsThe cohort included 354 patients; 59% female; age at diagnosis of 50.0 (±14) years; 39% were antineutrophil cytoplasm antibody (ANCA) positive. Time from diagnosis to last follow‐up was 7.0 (±6.2) years; 49.4% had one or more relapse. Patients positive for ANCA more commonly had neurological and kidney involvement when compared with patients negative for ANCA, who had more cardiac and lung manifestations. At last study visit, only 35 (12.6%) patients had been off all therapy for more than 2 years during their follow‐up. The overall mortality rate was 4.0% and did not differ by ANCA status or cyclophosphamide use. Scores on the Vasculitis Damage Index (VDI) for 134 patients with two or more visits and more than 1 year of follow‐up increased from 1.7 (±1.8) at enrollment (3.7 [±5.1] years after diagnosis) to 3.35 (±2.1) at last follow‐up (7.5 [±5.8] years after diagnosis), mainly represented by chronic asthma (67.5%), peripheral neuropathy (49.6%), and chronic sinusitis (31.3%). Longer duration of glucocorticoid use and relapse were associated with higher VDI scores.ConclusionThis analysis describes the many clinical manifestations and varied outcomes of EGPA and highlights the ongoing need to attain more sustained, long‐term remission to limit the accrual of disease‐related damage.

ObjectiveDeficiency of adenosine deaminase 2 (DADA2) is a monogenic form of vasculitis that can resemble polyarteritis nodosa (PAN). This study was undertaken to identify potential disease‐causing sequence variants in ADA2 in patients with idiopathic PAN, granulomatosis with polyangiitis (GPA), or microscopic polyangiitis (MPA).MethodsPatients with idiopathic PAN (n = 118) and patients with GPA or MPA (n = 1,107) were screened for rare nonsynonymous variants in ADA2 using DNA sequencing methods. ADA‐2 enzyme activity was assessed in selected serum samples.ResultsNine of 118 patients with PAN (7.6%) were identified as having rare nonsynonymous variants in ADA2. Four patients (3.4%) were biallelic for pathogenic or likely pathogenic variants, and 5 patients (4.2%) were monoallelic carriers for 3 variants of uncertain significance and 2 likely pathogenic variants. Serum samples from 2 patients with PAN with biallelic variants were available and showed markedly reduced ADA‐2 enzyme activity. ADA‐2 enzyme testing of 86 additional patients revealed 1 individual with strongly reduced ADA‐2 activity without detectable pathogenic variants. Patients with PAN and biallelic variants in ADA2 were younger at diagnosis than patients with 1 or no variant in ADA2, with no other clinical differences noted. None of the patients with GPA or MPA carried biallelic variants in ADA2.ConclusionA subset of patients with idiopathic PAN meet genetic criteria for DADA2. Given that tumor necrosis factor inhibition is efficacious in DADA2 but is not conventional therapy for PAN, these findings suggest that ADA‐2 testing should strongly be considered in patients with hepatitis B virus–negative idiopathic PAN.

BACKGROUND Baseline expression of FCRL5 , a marker of naive and memory B cells, was shown to predict response to rituximab (RTX) in rheumatoid arthritis. This study investigated baseline expression of FCRL5 as a potential biomarker of clinical response to RTX in granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA). METHODS A previously validated quantitative PCR–based (qPCR-based) platform was used to assess FCRL5 expression in patients with GPA/MPA (RAVE trial, NCT00104299). RESULTS Baseline FCRL5 expression was significantly higher in patients achieving complete remission (CR) at 6, 12, and 18 months, independent of other clinical and serological variables, among those randomized to RTX but not cyclophosphamide-azathioprine (CYC/AZA). Patients with baseline FCRL5 expression ≥ 0.01 expression units (termed FCRL5 hi ) exhibited significantly higher CR rates at 6, 12, and 18 months as compared with FCRL5 lo subjects (84% versus 57% [ P = 0.016], 68% versus 40% [ P = 0.02], and 68% versus 29% [ P = 0.0009], respectively). CONCLUSION Our data taken together suggest that FCRL5 is a biomarker of B cell lineage associated with increased achievement and maintenance of complete remission among patients treated with RTX and warrant further investigation in a prospective manner. FUNDING The analysis for this study was funded by Genentech Inc.

ObjectiveThe present study was undertaken to conduct a phase IV, open‐label, prospective study to characterize the long‐term safety of rituximab in a 4‐year observational registry of adult patients with granulomatosis with polyangiitis (GPA) or microscopic polyangiitis (MPA) within the US.MethodsPatients initiating treatment with rituximab were evaluated every 6 months for up to 4 years. Outcomes included the incidence of serious adverse events (SAEs), infusion‐related reactions (IRRs), and SAEs of specific interest, including serious infections, serious cardiac events, serious vascular events, and malignancies.ResultsOverall, 97 patients (72 with GPA and 25 with MPA) received rituximab through a median of 8 (range 1–28) infusions and were followed up for a median of 3.94 years (range 0.05–4.32 years). The estimated incidence rates (95% confidence interval [95% CI]) of serious infections, serious cardiac events, and serious vascular events were 7.11 (4.55–10.58), 5.03 (2.93–8.06), and 2.37 (1.02–4.67) per 100 patient‐years (PYs), respectively. No IRRs or SAEs occurred within 24 hours of an infusion of rituximab. None of the 9 deaths reported (crude mortality rate 2.67 [95% CI 1.22–5.06] per 100 PYs) were considered to be related to use of rituximab.ConclusionThe safety profile of long‐term treatment with rituximab in patients with GPA or MPA was consistent with that of rituximab administered for shorter durations and with rituximab’s known safety profile in other autoimmune diseases for which it has received regulatory approval. These findings provide clinicians with long‐term, practice‐level safety data for rituximab in the treatment of GPA or MPA.

Objective To identify and validate, using computer‐driven methods, patterns of arterial disease in Takayasu arteritis (TAK) and giant cell arteritis (GCA). Methods Patients with TAK or GCA were studied from the Diagnostic and Classification Criteria for Vasculitis (DCVAS) cohort and a combined North American cohort. Case inclusion required evidence of large‐vessel involvement, defined as stenosis, occlusion, or aneurysm by angiography/ultrasonography, or increased 18 F‐fluorodeoxyglucose (FDG) uptake by positron emission tomography (PET) in at least 1 of 11 specified arterial territories. K‐means cluster analysis identified groups of patients based on the pattern of arterial involvement. Cluster groups were identified in the DCVAS cohort and independently validated in the North American cohort. Results A total of 1,068 patients were included (DCVAS cohort: TAK = 461, GCA = 217; North American cohort: TAK = 225, GCA = 165). Six distinct clusters of patients were identified in DCVAS and validated in the North American cohort. Patients with TAK were more likely to have disease in the abdominal vasculature, bilateral disease of the subclavian and carotid arteries, or focal disease limited to the left subclavian artery than GCA ( P < 0.01). Patients with GCA were more likely to have diffuse disease, involvement of bilateral axillary/subclavian arteries, or minimal disease without a definable pattern than TAK ( P < 0.01). Patients with TAK were more likely to have damage by angiography, and patients with GCA were more likely to have arterial FDG uptake by PET without associated vascular damage. Conclusion Arterial patterns of disease highlight both shared and divergent vascular patterns between TAK and GCA and should be incorporated into classification criteria for large‐vessel vasculitis.