Anti-neutrophilic cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) are a group of rare auto-inflammatory diseases that affects mainly small vessels. AAV includes: granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA) and eosinophilic granulomatosis with polyangiitis (EGPA). Anti-cytokine targeted therapy uses biological agents capable of specifically targeting and neutralising cytokine mediators of the inflammatory response.
To assess the benefits and harms of anti-cytokine targeted therapy for adults with AAV.
We searched the Cochrane Central Register of Controlled Trials (2019, Issue 7), MEDLINE and Embase up to 16 August 2019. We also examined reference lists of articles, clinical trial registries, websites of regulatory agencies and contacted manufacturers.
Randomised controlled trials (RCTs) or controlled clinical trials of targeted anti-cytokine therapy in adults (18 years or older) with AAV compared with placebo, standard therapy or another modality and anti-cytokine therapy of different type or dose.
We used standard methodological procedures expected by Cochrane.
We included four RCTs with a total of 440 participants (mean age 48 to 56 years). We analysed the studies in three groups: 1) mepolizumab (300 mg; three separate injections every four weeks for 52 weeks) versus placebo in participants with relapsing or refractory EGPA; 2) belimumab (10 mg/kg on days 0, 14, 28 and every 28 days thereafter until 12 months after the last participant was randomised) or etanercept (25 mg twice a week) with standard therapy (median 25 months) versus placebo with standard therapy (median 19 months) in participants with GPA/MPA; and 3) infliximab (3 mg/kg on days 1 and 14, before the response assessment on day 42) versus rituximab (0.375g/m
We found four studies but concerns about risk of bias and small sample sizes preclude firm conclusions. We found moderate-certainty evidence that in patients with relapsing or refractory EGPA, mepolizumab compared to placebo probably decreases disease relapse and low-certainty evidence that mepolizumab may increase the probability of accruing at least 24 weeks of disease remission. There were similar frequencies of total and serious AEs in both groups, but the study was too small to reliably assess these outcomes. Mepolizumab may result in little to no difference in mortality. However, there were very few events. In participants with GPA (and a small subgroup of participants with MPA), etanercept or belimumab may increase the probability of withdrawal due to AEs and may have little to no impact on serious AEs. Etanercept may have little or no impact on durable remission and probably does not reduce disease flare.