Current and Future Treatment Options for Eosinophilic Granulomatosis With Polyangiitis

Anti-cytokine targeted therapies for ANCA-associated vasculitis

BACKGROUND

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.

OBJECTIVES

To assess the benefits and harms of anti-cytokine targeted therapy for adults with AAV.

SEARCH METHODS

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.

SELECTION CRITERIA

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.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

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/m2 on days 1, 8, 15 and 22) in participants with refractory GPA for up to 12 months. None of the studies were assessed as low risk of bias in all domains: one study did not report randomisation or blinding methods clearly. Three studies were at high risk and one study was at unclear risk of bias for selective outcome reporting. One trial with 136 participants with relapsing or refractory EGPA compared mepolizumab with placebo during 52 weeks of follow-up and observed one death in the mepolizumab group (1/68, 1.5%) and none in the placebo group (0/68, 0%) (Peto odds ratio (OR) 7.39, 95% confidence interval (CI) 0.15 to 372.38; low-certainty evidence). Low-certainty evidence suggests that more participants in the mepolizumab group had ≥ 24 weeks of accrued remission over 52 weeks compared to placebo (27.9% versus 2.9%; risk ratio (RR) 9.5, 95% CI 2.30 to 39.21), and durable remission within the first 24 weeks sustained until week 52 (19.1% mepolizumab versus 1.5% placebo; RR 13.0, 95% CI 1.75 to 96.63; number needed to treat for an additional beneficial outcome (NNTB) 6, 95% Cl 4 to 13). Mepolizumab probably decreases risk of relapse (55.8% versus 82.4%; RR 0.68, 95% CI 0.53 to 0.86; NNTB 4, 95% CI 3 to 9; moderate-certainty evidence). There was low-certainty evidence regarding similar frequency of adverse events (AEs): total AEs (96.9% versus 94.1%; RR 1.03, 95% CI 0.96 to 1.11), serious AEs (17.7% versus 26.5%; RR 0.67, 95% CI 0.35 to 1.28) and withdrawals due to AEs (2.9% versus 1.5%; RR 2.00, 95% CI 0.19 to 21.54). Disease flares were not measured. Based on two trials with different follow-up periods (mean of 27 months for etanercept study; up to four years for belimumab study) including people with GPA (n = 263) and a small group of participants with MPA (n = 22) analysed together, we found low-certainty evidence suggesting that adding an active drug (etanercept or belimumab) to standard therapy does not increase or reduce mortality (3.4% versus 1.4%; Peto OR 2.45, 95% CI 0.55 to 10.97). Etanercept may have little or no effect on remission (92.3% versus 89.5%; RR 0.97, 95% CI 0.89 to 1.07), durable remission (70% versus 75.3%; RR 0.93, 95% CI 0.77 to 1.11; low-certainty evidence) and disease flares (56% versus 57.1%; RR 0.98, 95% CI 0.76 to 1.27; moderate-certainty evidence). Low-certainty evidence suggests that belimumab does not increase or reduce major relapse (1.9% versus 0%; RR 2.94, 95% CI 0.12 to 70.67) or any AE (92.5% versus 82.7%; RR 1.12, 95% CI 0.97 to 1.29). Low-certainty evidence suggests a similar frequency of serious or severe AEs (47.6% versus 47.6%; RR 1.00, 95% CI 0.80 to 1.27), but more frequent withdrawals due to AEs in the active drug group (11.2%) compared to the placebo group (4.2%), RR 2.66, 95% CI 1.07 to 6.59). One trial involving 17 participants with refractory GPA compared infliximab versus rituximab added to steroids and cytotoxic agents for 12 months. One participant died in each group (Peto OR 0.88, 95% CI, 0.05 to 15.51; 11% versus 12.5%). We have very low-certainty evidence for remission (22% versus 50%, RR 0.44, 95% Cl 0.11 to 1.81) and durable remission (11% versus 50%, RR 0.22, 95% CI 0.03 to 1.60), any severe AE (22.3% versus 12.5%; RR 1.78, 95% CI 0.2 to 16.1) and withdrawals due to AEs (0% versus 0%; RR 2.70, 95% CI 0.13 to 58.24). Disease flare/relapse and the frequency of any AE were not reported.

AUTHORS' CONCLUSIONS

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.

Lung involvement in ANCA-associated vasculitis

Lung involvement is one of the most common clinical features in ANCA-associated vasculitides (AAV), including granulomatosis with polyangiitis (GPA), microscopic polyangiitis (MPA), and eosinophilic granulomatosis with polyangiitis (EGPA). In this review, we detail the five main presentations of pulmonary involvement in AAV: necrotizing granulomatous inflammation, tracheobronchial inflammation, pulmonary capillaritis, interstitial lung disease (ILD) and asthma with their clinical, radiological and therapeutic characteristics. The prevalence of these manifestations is variable according to the subtype of AAV, necrotizing granulomatous inflammation and tracheobronchial inflammation being defining features of GPA whereas ILD is primarily seen in patients with MPA, especially in association with ANCA directed against myeloperoxydase (MPO-ANCA), and asthma is characteristic of EGPA. Despite recent progresses in the diagnosis and management of these conditions, several questions remain and are discussed here, including local treatments for subglottic stenosis, the uncertain efficacy of plasma exchanges for alveolar hemorrhage, the potential role of antifibrotic agents in ILD associated with MPA, and the use of novel anti-IL-5 strategies in EGPA.

Eosinophilic Granulomatosis With Polyangiitis: Clinical Predictors of Long-term Asthma Severity

BACKGROUND

The long-term clinical course of asthma in patients with eosinophilic granulomatosis with polyangiitis (EGPA) remains unclear. We aimed to characterize long-term asthma in EGPA and to identify baseline predictors of long-term asthma severity.

METHODS

This retrospective cohort study included patients who fulfilled standardized criteria for EGPA who were followed up in a single referral center between 1990 and 2017. Baseline and 3 (± 1) years of follow-up clinical, laboratory, and pulmonary function data were analyzed.

RESULTS

Eighty-nine patients with EGPA and a documented asthma assessment at baseline and at 3 years from diagnosis were included. Severe/uncontrolled asthma was observed in 42.7% of patients at diagnosis and was associated with previous history of respiratory allergy (P < .01), elevated serum total IgE levels (P < .05), and increased use of high-dose inhaled corticosteroids (ICSs; P < .05) and oral corticosteroids (OCSs; P < .001) for respiratory symptoms the year before the EGPA diagnosis. During follow-up, an improvement or worsening in asthma severity was noted in 12.3% and 10.1% of patients, respectively. Severe/uncontrolled asthma was present in 40.5% of patients at 3 years and was associated with increased airway resistance on pulmonary function tests (PFTs; P < .05). Long-term PFTs did not improve during long-term follow-up regardless of ICS or OCS therapy. Multivariate binary logistic regression results indicated that severe rhinosinusitis (P = .038), pulmonary infiltrates (P = .011), overweight (BMI ≥ 25 kg/m²; P = .041), and severe/uncontrolled asthma at vasculitis diagnosis (P < .001) independently predicted severe/uncontrolled asthma at the 3-year end point.

CONCLUSIONS

In patients with asthma with EGPA, long-term severe/uncontrolled asthma is associated with baseline pulmonary and ear, nose, and throat manifestations but not with clear-cut vasculitic features.

Eosinophilic granulomatosis with polyangiitis: the multifaceted spectrum of clinical manifestations at different stages of the disease

Introduction: Eosinophilic granulomatosis with polyangiitis (EGPA) usually occurs in patients with late-onset asthma and sustained peripheral blood eosinophilia and classically presents with a clinical multifaceted spectrum of manifestations, which may vary at the different stages of the natural history of the disease.Areas covered: We reviewed EGPA clinical presentation, focusing on clinical manifestations at three different phases of the disease: 1/before the development of overt vasculitis, 2/at vasculitis diagnosis and 3/during the long-term follow-up. An update on current classification criteria and recent therapeutic advances has been provided as well.Expert opinion: Asthma, chronic rhinosinusitis and blood eosinophilia could anticipate the overt vasculitis for years. An atopic background may be present in a subset of patients (25-30%), while ANCA presence varies between 10 and 40%. Systemic vasculitis rapidly occurs and clinical features demonstrating vasculitis processes (neuropathy, purpura, scleritis, alveolar hemorrhage and glomerulonephritis) develop along with systemic symptoms (50%). After vasculitis resolution, asthma remains severe in up to 50% of patients and incidence of isolated-asthma and rhinosinus exacerbations remains constantly high. Different sets of classification criteria have been published so far, and DCVAS diagnostic criteria will be presented soon. Interleukin-5 blockers seem to be promising to control the disease and to spare corticosteroids.