Treatments of refractory eosinophilic lung diseases with biologics

Critical deterioration of chronic eosinophilic pneumonia during pregnancy

Chronic eosinophilic pneumonia (CEP) is a rare, idiopathic interstitial lung disease characterised by the accumulation of eosinophils in the pulmonary interstitia and alveoli. Patients with CEP respond well to systemic corticosteroid therapy and infrequently progress to end-stage lung disease. We report a case of a woman in her 40s with previously stable, steroid-responsive CEP who experienced a critical deterioration of her CEP at 25 weeks of gestation during her third pregnancy. The patient was admitted to the intensive care unit due to respiratory failure requiring intubation and mechanical ventilation. Follow-up investigation revealed advanced fibrotic lung disease requiring long-term oxygen therapy and referral for double lung transplantation. While CEP infrequently advances to permanent parenchymal damage, this case demonstrates the potential for severe exacerbations in the setting of pregnancy and highlights pregnancy as a potential risk factor for disease progression, reinforcing the need for further research to define optimal monitoring and treatment strategies.

Monoclonal antibodies in idiopathic chronic eosinophilic pneumonia: a scoping review

BACKGROUND

Idiopathic chronic eosinophilic pneumonia (ICEP) is a rare disease characterized by pulmonary radiological alterations, peripheral eosinophilia, and demonstrated pulmonary eosinophilia. Oral steroids (OSs) are the standard management, but relapses occur in up to 50% of patients during the decrease or suspension of steroids, usually requiring reinitiation of treatment, exposing patients to secondary events derived from the management. Management with monoclonal antibodies has been proposed in these cases to control the disease and limit the secondary effects. The objective is to describe the extent and type of evidence regarding the use of monoclonal antibodies for ICEP.

METHODS

A panoramic review of the literature was performed. Observational and experimental studies of pediatric and adult populations that managed recurrent ICEP with monoclonal antibodies were included. Data search, selection, and extraction were performed by two independent reviewers.

RESULTS

937 studies were found. After applying the inclusion and exclusion criteria, 37 titles remained for the final analysis: a retrospective, observational, real-life study, two case series publications, and 34 case reports published in academic poster sessions and letters to the editor. In general, the use of monoclonal antibodies approved for severe asthma could be useful for the control of ICEP, since most of the results show a good response for clinical and radiological outcomes. Biological drugs seem to be a safer option for controlling relapses in ICEP, allowing lowering/suspension of OSs, and sometimes replacing them in patients intolerant to them, patients with significant comorbidities, and patients who have already developed adverse events.

CONCLUSION

The extent of the evidence supporting management of ICEP with monoclonal antibodies against IL-5 and IgE (omalizumab) is limited, but it could be promising in patients who present frequent relapses, in cortico-dependent individuals, or in patients in whom the use of steroids is contraindicated. The extent of the evidence for management with dupilumab is more limited. Studies with better design and structure are needed to evaluate quality of life and outcomes during a clear follow-up period. To our knowledge, this is the first scoping review of the literature showing the extent of the evidence for the management of ICEP with monoclonal antibodies.

Allergic bronchopulmonary aspergillosis with atopic, nonatopic, and sans asthma-Factor analysis

BACKGROUND

Allergic bronchopulmonary aspergillosis (ABPA) develops in the presence or absence of asthma, either atopic or nonatopic. We have tried to explore the essential components in the pathogenesis of the disease, which are either consistent and variable according to the presence and type of asthma.

METHODS

Non-cystic fibrosis ABPA cases satisfying Asano's criteria were extracted from a prospective registry of ABPA and related diseases in Japan between 2013 and 2023. According to the type of preceding asthma, ABPA was classified into three groups: ABPA sans asthma (no preceding asthma), ABPA with atopic asthma, and ABPA with nonatopic asthma. Exploratory and confirmatory factor analyses were performed to identify the components that determined the clinical characteristics of ABPA.

RESULTS

Among 106 cases of ABPA, 25 patients (24%) had ABPA sans asthma, whereas 57 (54%) and 24 (23%) had ABPA with atopic and nonatopic asthma, respectively. Factor analysis identified three components: allergic, eosinophilic, and fungal. Patients with atopic asthma showed the highest scores for the allergic component (p < .001), defined by total and allergen-specific IgE titers and lung opacities, and the lowest scores for the fungal component defined by the presence of specific precipitin/IgG or positive culture for A. fumigatus. Eosinophilic components, including peripheral blood eosinophil counts and presence of mucus plugs/high attenuation mucus in the bronchi, were consistent among the three groups.

CONCLUSION

The eosinophilic component of ABPA is considered as the cardinal feature of ABPA regardless of the presence of preceding asthma or atopic predisposition.

Allergic fungal rhinosinusitis: What we can learn from allergic bronchopulmonary mycosis

Allergic fungal rhinosinusitis (AFRS) and allergic bronchopulmonary mycosis (ABPM) are inflammatory disorders of the respiratory tract resulting from type 1 and 3 hypersensitivity reactions against fungi. The hallmark features of both diseases are eosinophil infiltration into the airway mucosa caused by localized type 2 inflammation and concomitant viscid secretions in the airways. Eosinophilic mucin-induced compression of adjacent anatomic structures leads to bone erosion and central bronchiectasis in the upper and lower respiratory tracts, respectively. Although these diseases share common features in their pathogenesis, they also exhibit notable differences. Epidemiologic findings are diverse, with AFRS typically presenting at a younger age, exhibiting less complicated bronchial asthma, and displaying lower total immunoglobulin E levels in laboratory findings compared with ABPM. Furthermore, despite their similar pathogenesis, the rarity of sinio-bronchial allergic mycosis in both AFRS and ABPM underscores the distinctions between these two diseases. This review aims to clarify the similarities and differences in the pathogenesis of AFRS and ABPM to determine what can be learned about AFRS from ABPM, where more is known.

Eosinophilic granulomatosis with polyangiitis - Advances in pathogenesis, diagnosis, and treatment

Eosinophilic granulomatosis with polyangiitis (EGPA) is a rare disease characterized by eosinophil-rich granulomatous inflammation and necrotizing vasculitis, pre-dominantly affecting small-to-medium-sized vessels. It is categorized as a primary antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAVs) but also shares features of hypereosinophilic syndrome (HES); therefore, both vessel inflammation and eosinophilic infiltration are suggested to cause organ damage. This dual nature of the disease causes variable clinical presentation. As a result, careful differentiation from mimicking conditions is needed, especially from HES, given the overlapping clinical, radiologic, and histologic features, and biomarker profile. EGPA also remains a diagnostic challenge, in part because of asthma, which may pre-dominate for years, and often requires chronic corticosteroids (CS), which can mask other disease features. The pathogenesis is still not fully understood, however, the interaction between eosinophils and lymphocytes B and T seems to play an important role. Furthermore, the role of ANCA is not clear, and only up to 40% of patients are ANCA-positive. Moreover, two ANCA-dependent clinically and genetically distinct subgroups have been identified. However, a gold standard test for establishing a diagnosis is not available. In practice, the disease is mainly diagnosed based on the clinical symptoms and results of non-invasive tests. The unmet needs include uniform diagnostic criteria and biomarkers to help distinguish EGPA from HESs. Despite its rarity, notable progress has been made in understanding the disease and in its management. A better understanding of the pathophysiology has provided new insights into the pathogenesis and therapeutic targets, which are reflected in novel biological agents. However, there remains an ongoing reliance on corticosteroid therapy. Therefore, there is a significant need for more effective and better-tolerated steroid-sparing treatment schemes.

Real-world efficacy of anti-IL-5 treatment in patients with allergic bronchopulmonary aspergillosis

Despite standard treatment with systemic corticosteroids and/or antifungal triazoles, a substantial proportion of patients with allergic bronchopulmonary aspergillosis (ABPA) experience frequent relapses and require long-term treatment despite unfavorable adverse effects. We investigated the efficacy and safety of anti-interleukin (IL)-5/IL-5 receptor α chain (Rα) monoclonal antibodies (mAbs) in patients with ABPA complicated by asthma. ABPA cases treated with anti-IL-5/IL-5Rα mAbs were collected from 132 medical institutes in 2018 and published case reports in Japan. Clinical outcomes, laboratory and physiological data, and radiographic findings during 32 weeks before and after treatment were retrospectively evaluated. We analyzed 29 cases of ABPA: 20 treated with mepolizumab and nine with benralizumab. Treatment with anti-IL-5/IL-5Rα mAbs reduced the frequency of exacerbations (p = 0.03), decreased the dose of oral corticosteroids (p < 0.01), and improved pulmonary function (p = 0.01). Mucus plugs in the bronchi shrank or diminished in 18 patients (82%). Despite the clinical/radiographical improvement, serum levels of total IgE, the key biomarker for the pharmacological response in ABPA, were unchanged. Anti-IL-5/IL-5Rα mAbs that directly target eosinophils are promising candidates for the treatment of patients with ABPA, especially those with mucus plugs in the bronchi.