Targeting eosinophils: severe asthma and beyond

Eosinophil-derived extracellular vesicles: isolation and classification techniques and implications for disease pathophysiology

Eosinophils are leukocytes characterized by their ability to release granule content that is highly rich in enzymes and proteins. Besides the antihelminthic, bactericidal, and antiviral properties of eosinophils and their secretory granules, these also play a prominent role in the pathophysiology of diseases such as asthma, eosinophilic esophagitis, and other hypereosinophilic conditions by causing tissue damage and airway hyperresponsiveness. Although this cell was first recognized mainly for its capacity to release granule content, nowadays other capabilities such as cytokine secretion have been linked to its physiology, and research has found that eosinophils are not only involved in innate immunity, but also as orchestrators of immune responses. Nearly 10 yr ago, eosinophil-derived extracellular vesicles (EVs) were first described; since then, the EV field has grown exponentially, revealing their vital roles in intracellular communication. In this review, we synthesize current knowledge on eosinophil-derived EVs, beginning with a description of what they are and what makes them important regulators of disease, followed by an account of the methodologies used to isolate and characterize EVs. We also summarize current understanding of eosinophil-derived vesicles functionality, especially in asthma, the disease in which eosinophil-derived EVs have been most widely studied, describing how they modulate the role of eosinophils themselves (through autocrine signaling) and the way they affect airway structural cells and airway remodeling. Deeper understanding of this cell type could lead to novel research in eosinophil biology, its role in other diseases, and possible use of eosinophil-derived EVs as therapeutic targets.

Real-World Safety Profile of Biologic Drugs for Severe Uncontrolled Asthma: A Descriptive Analysis from the Spanish Pharmacovigilance Database

Background: The present investigation provides a thorough analysis of adverse drug reactions (ADRs) reported in the Database of the Spanish Pharmacovigilance System (FEDRA) for biologic medications primarily indicated for severe refractory asthma, including omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab, and tezepelumab. Our main objective was to identify ADRs not documented in the drugs' Technical Sheets (summary of product characteristics, SmPC), potentially indicating unrecognized risks meriting pharmacovigilance attention. Methods: Data spanning from each drug's market introduction until 22 January 2024, were analyzed, sourced from direct submissions to the Spanish Pharmacovigilance System, industry communications, and literature reviews. We evaluated notifications impartially to ensure a comprehensive review of all the ADRs associated with these medications. Results: This investigation underlines the critical role of post-marketing surveillance in enhancing patient safety. It emphasizes the necessity for healthcare professionals to report ADRs comprehensively to foster a robust pharmacovigilance system. Furthermore, the study highlights gaps between the reported ADRs and the information provided in SmPCs, signaling potential areas for improvement in drug safety monitoring and regulatory oversight. Conclusions: Finally, these findings may contribute to informed decision making in clinical practice and regulatory policy, ultimately advancing patient care and safety in the management of severe uncontrolled asthma.

IL-13 and IL-13-induced periostin levels are specifically decreased in patients following endoscopic sinus surgery for chronic rhinosinusitis

BACKGROUND

Type 2 (T2) inflammation plays a pathogenic role in chronic rhinosinusitis (CRS). The effects of endoscopic sinus surgery (ESS) on T2 inflammation are unknown.

OBJECTIVE

The aim of this study was to compare T2 inflammatory biomarkers from middle meatal (MM) mucus for distinguishing patients with CRS from CRS-free patients, identifying major phenotypes (CRS without nasal polyps [CRSsNP] and CRS with nasal polyps [CRSwNP]), assessing endotypic change, and establishing cross-sectional and longitudinal outcomes in patients undergoing ESS.

METHODS

MM mucus samples were collected from patients with CRSsNP and patients with CRSwNP before and 6 to 12 months after ESS and compared with samples from CRS-free control patients. T2 biomarkers were evaluated both continuously and using threshold-based definitions of T2 endotype to identify relationships with patient-reported (based on the 22-Item Sinonasal Outcomes Test and Chronic Rhinosinusitis Patient-Reported Outcomes Measure) and clinician-reported (radiographic and endoscopic) severity. Linear mixed models were developed to analyze clinical variables associated with T2 biomarker levels.

RESULTS

A total of 154 patients with CRS (89 with CRSsNP and 65 with CRSwNP) were enrolled, with a mean interval of 9 months between ESS and follow-up. An analysis of pre-ESS MM mucus samples revealed elevated levels of T2 mediators in patients with CRSwNP versus in patients with CRSsNP and CRS-free controls. Temporally stable correlations between levels of IL-13 and IL-5, levels of periostin and complement 5a, and levels of eosinophil cationic protein (ECP) and eotaxin-3 were observed. On this basis and on the basis of pathologic significance, levels of IL-13, periostin and ECP were further analyzed. After ESS, levels of IL-13 and periostin decreased significantly, whereas ECP levels remained unchanged. Across pre- and post-ESS evaluation, the T2 endotype was associated with radiographic severity but did not predict outcomes. CRSwNP status and African American race were associated with higher levels of IL-13 and periostin, whereas ECP level was higher in patients undergoing extensive surgery.

CONCLUSION

ESS decreased levels of IL-13 and periostin in the middle meatus. T2 inflammation after ESS was correlated with patient- and clinician-reported severity across phenotypes. Pre-ESS T2 inflammation did not predict post-ESS outcomes.

Anti-IL-5 biologics and rheumatoid arthritis: a single-centre 500 patient year exposure analysis

OBJECTIVE

The increasing use of biological therapies has led to the paradoxical finding that monoclonal antibody therapy for one inflammatory disease can sometimes induce another inflammatory disease. Recently, the use of anti-IL-5 (IL, interleukin) antibody therapies for severe asthma has been associated with the onset of rheumatoid arthritis (RA) and other inflammatory rheumatological disease. We undertook this audit to identify the prevalence of this finding across a large clinical cohort of patients receiving anti-IL-5 therapy.

METHODS

All patients currently receiving mepolizumab or benralizumab for severe asthma across the Leeds Teaching Hospitals NHS Trust's (LTHT) Respiratory Service were included. Electronic records for each patient were searched to identify clinical and biochemical manifestations of inflammatory rheumatological disease following the initiation of anti-IL-5 therapy.

RESULTS

142 patients, with a mean duration of 3.5 years on therapy, were included (89 mepolizumab, 53 benralizumab). 17 patients developed new arthralgias (nine mepolizumab, eight benralizumab), however only one of these patients (on mepolizumab) had raised acute phase reactants and newly positive anti-CCP antibody (ACPA) and rheumatoid factor and was the only patient to receive a formal diagnosis of RA.

CONCLUSION

Although ACPA positive RA has now been reported in a handful of case reports, we noted a very low rate of evolution into RA or inflammatory arthritis, at least in the short-medium term under anti-IL-5 therapy. This challenges the emerging suggestion that anti-IL-5 biologics may be triggering RA.

The role of anti-eosinophilic therapies in eosinophilic granulomatosis with polyangiitis: a systematic review

Eosinophilic granulomatosis with polyangiitis (EGPA) is an antineutrophil cytoplasmic antibody (ANCA)-associated vasculitis, mostly affecting small-sized arteries and usually occurring in patients with an allergic background. Eosinophils seem to play a significant role in the pathogenesis of the disease and, therefore, biologics targeting interleukin 5 (IL5), a cytokine tightly linked to eosinophils, have emerged as a promising therapeutic tool. A systematic review of Medline was conducted from 2007 to 2022 to search for data regarding the use of anti-IL5 therapies in patients with EGPA. Ongoing or unpublished trials were also searched in ClinicalTrials.gov and the World Health Organization trials portal. The efficacy and safety of mepolizumab, an anti-IL5 monoclonal antibody (mAb), was confirmed by a randomized controlled trial (RCT), although a significant proportion of patients did not respond to this treatment. Other studies showed that both doses of 100 mg and 300 mg of mepolizumab are almost equally effective in EGPA. Benralizumab, an anti-IL5 receptor mAb has preliminary promising results and an RCT is planned to be conducted. Apart from their clinical efficacy in EGPA, anti-IL5 therapies may have steroid-sparing properties. Anti-IL5 therapies seem to be effective and safe in patients with refractory/relapsing EGPA and can be used as a steroid-sparing treatment. Nevertheless, more research is needed to clarify the pathophysiology of the disease; this may potentially lead to the identification of biomarkers to pinpoint patients most likely to respond to anti-IL5-blockade.

Apurinic/apyrimidinic endonuclease 1 mRNA level in peripheral blood neutrophils is associated with asthma

Apurinic/apyrimidinic endonuclease 1 (APE1) is a multifunc-tional key protein. Recent studies suggest APE1 is closely associated with in-flammatory response, but its role in asthma remains unknown. We recruited 116 patients with asthma, including 50 with severe asthma (NSA) and 66 with non-severe asthma (SA), and 140 controls. Serum APE1 was detected using the ELISA method. APE1 mRNA in peripheral blood neutrophils and eosinophils were detected using real-time PCR assays. Compared to healthy controls, we observed significant elevations of serum APE1 mRNA levels in peripheral neu-trophils (~1.75 folds increase, p<0.05) and eosinophils (~2.2 folds increase, p<0.05) in patients with asthma. The peripheral blood neutrophil APE1 mRNA can distinguish asthmatic patients from healthy controls with the area under the curve (AUC) 0.893 and a 95% confidence interval (CI) 0.847-0.938 (p < 0.001). Also the APE1 mRNA can identify severe asthma from non-severe asth-ma (AUC 0.759, 95% CI, 0.674-0.846; p < 0.001). However, The serum APE1 and eosinophil mRNA levels did not correlate with asthma incidence and sever-ity. Our finding confirms the association between APE1 and asthma and sug-gests that peripheral blood neutrophil APE1 mRNA may be used as a marker for this condition.

Histological remission of eosinophilic esophagitis under asthma therapy with IL-5 receptor monoclonal antibody: A case report

BACKGROUND

Benralizumab is a monoclonal antibody targeting the IL-5 receptor used in the treatment of asthma. The use of benralizumab in other conditions is only emerging and could represent a therapeutic option for other eosinophil-associated diseases. Here, we report the case of a patient suffering from eosinophilic esophagitis and asthma who achieved histological remission of eosinophilic esophagitis (EoE) under benralizumab treatment for his asthma.

CASE SUMMARY

Our patient was a 56-year-old white male with a history of eosinophilic esophagitis and severe asthma. After years of usual treatments, including topical steroids, biological treatment with mepolizumab, and standard asthma treatment, only poor control of both conditions was obtained. A control gastroscopy after the initiation of benralizumab showed complete histological remission of his EoE.

CONCLUSION

Our case shows the effects of therapy with a novel agent not yet approved for this condition but for other diseases, with histological resolution of EoE after treatment. Complete clinical remission was not observed, which exemplifies the complex nature of EoE, its associated psychosomatic burden, and the chronification of the disease. Nevertheless, monoclonal antibodies targeting the Th2 response and, in our case, an IL5 receptor antagonist, achieved complete histological remission, which was not the case with an antibody against IL-5, which was also initiated to treat asthma.

Exploring the efficacy and contribution of Dupilumab in asthma management

IgG4 monoclonal antibody Dupilumab binds to the alpha chain (IL4R) of both types of the ligand-binding domains (IL4R/ IL13R1; equally IL4 and IL13 specific) of the IL-4 receptor. The current focus on precision medicine techniques to blocking pathways implicated in allergy disorders is crucial to the development of Dupilumab and broadening its therapeutic uses. Our review describes how the IL-4R complexes signaling pathway works, explores the probable mechanisms of Dupilumab activity and addresses its clinical usefulness and safety in asthma. The FDA (Food and Drug Administration) already licences it to treat Alzheimer's disease and moderate-to-severe asthma, and it has shown highly significant results in the management of chronic rhinosinusitis and Eosinophilic esophagitis (EoE). Previous investigations and clinical trials undertaken by various pharmaceutical firms are examined in this review article to assess the existing literature fully. The discovery of Dupilumab and the expanding range of therapeutic uses are pertinent to the current focus on precision medicine methods to blocking asthma-related pathways.

Switching from omalizumab to mepolizumab therapy improved extra-pulmonary abdominal and cutaneous vasculitis symptoms in a patient with eosinophilic granulomatosis with polyangiitis

Eosinophilic granulomatosis with polyangiitis (EGPA) is a systemic vasculitis of small-to-medium-sized vessels. Both eosinophilic infiltration and vasculitis are thought to contribute to multi-organ damage. Some biologics have been used to reduce the required dose of corticosteroids in EGPA, but no single agent can ensure a complete control of this disease. Here, we describe a patient with anti-neutrophil cytoplasmic antibodies-negative relapsing EGPA whose asthma control was improved by omalizumab, but she continued to develop flares of abdominal and cutaneous vasculitis symptoms. After switching to mepolizumab therapy, her blood hypereosinophilia and extra-pulmonary symptoms were significantly improved. Moreover, the dose of daily maintenance corticosteroid could be tapered off. The experience from our case suggests that biologics targeting interleukin-5 may be more effective than omalizumab in the management of extra-thoracic manifestations in EGPA.

Packaging and Delivery of Asthma Therapeutics

Asthma is a life-altering, chronic disease of heterogenous origin that features a complex interplay of immune and environmental signaling. Although very little progress has been made in prevention, diverse types of medications and delivery systems, including nanoscale systems, have been or are currently being developed to control airway inflammation and prevent exacerbations and fibrosis. These medications are delivered through mechanical methods, with various inhalers (with benefits and drawbacks) existing, and new types offering some variety in delivery. Of particular interest is the progress being made in nanosized materials for efficient penetration into the epithelial mucus layer and delivery into the deepest parts of the lungs. Liposomes, nanoparticles, and extracellular vesicles, both natural and synthetic, have been explored in animal models of asthma and have produced promising results. This review will summarize and synthesize the latest developments in both macro-(inhaler) and micro-sized delivery systems for the purpose of treating asthma patients.

Renal Involvement as Rare Acute Tubulointerstitial Nephritis in a Patient with Eosinophilic Disorder Treated with Early Add-on Administration of Mepolizumab

A 39-year-old man presented with peripheral eosinophilia, pulmonary eosinophilic infiltrate, and renal failure due to acute tubulointerstitial nephritis (TIN). He had experienced childhood asthma and was negative for anti-neutrophil cytoplasmic antibody (ANCA). He was tentatively diagnosed with ANCA-negative eosinophilic granulomatous polyangiitis (EGPA) or idiopathic hypereosinophilic syndrome (HES). Renal involvement of isolated TIN with eosinophil infiltration is rare in EGPA and HES and does not seem to have a good prognosis in the literature. However, his condition improved well with corticosteroids and mepolizumab. The revised classification of EGPA based on the etiology should dictate the proper treatment in suspected EGPA patients with nonsystemic vasculitis.

Severe hypereosinophilic syndrome successfully treated with a monoclonal antibody against interleukin 5 receptor α - benralizumab

Hypereosinophilic syndrome (HES) is a group of a rare diseases characterized by marked eosinophilia in blood or tissue and eosinophil-related clinical manifestations. Benralizumab is a humanized, monoclonal antibody against interleukin 5 (IL-5) receptor α, which is expressed on human eosinophils.

Here, we present the case of a patient with severe HES in whom treatment with benralizumab, an anti-IL-5 receptor monoclonal antibody, was initiated 6 months ago. Prior to benralizumab administration, the patient was treated with glucocorticoids (GS) and mepolizumab. However, instead of the applied treatment and normal level of peripheral eosinophils the patient presented with fluctuating lower respiratory tract symptoms and recurrent exacerbations of HES.

Treatment with benralizumab (30 mg s.c. every 4-6 weeks) was started, resulting in significant improvement of respiratory signs and symptoms, normalization of eosinophil count and significant reduction of the methylprednisolone dose (after 5 doses of benralizumab administration). No substantial side effects have been noted during treatment and 6-month follow-up.

We argue that in the severe and relapsing course of HES, rescue treatment with benralizumab should be taken into account, particularly in cases of relative inefficacy of GS and mepolizumab.

Reduction/elimination of blood eosinophils in severe asthma: should there be a safety consideration?

INTRODUCTION

Eosinophils play a central role in the inflammation of asthma and are the target of new biologic treatments for patients with severe asthma. Biologics targeting the IL-5 pathway have been shown to reduce asthma exacerbations, improve lung function, reduce oral corticosteroid use, and improve quality of life, accompanied by reduced or even eliminated blood eosinophils. Eosinophils have been associated with host protection and tumor growth, raising potential concerns about the consequences of these long-term therapies that reduce or eliminate them.

AREAS COVERED

In this review, we explore the current safety profile of biologics regarding the impact they may have on blood eosinophils, trying to answer the question about any safety consideration.

EXPERT OPINION

Eosinophils have been associated with host protection and tumor growth, raising potential concerns about the consequences of long-term therapies that reduce or eliminate these blood cells.

Mepolizumab for Eosinophilic Granulomatosis with Polyangiitis (EGPA): a European multicenter observational study

OBJECTIVE

Mepolizumab proved efficacious for eosinophilic granulomatosis with polyangiitis (EGPA, former Churg-Strauss) at the dosage of 300mg/4 weeks in the randomized controlled MIRRA trial. Few successful real-life experiences with the dosage approved for severe eosinophilic asthma (100mg/4 weeks) were recently reported. We retrospectively assessed the effectiveness and safety of mepolizumab 100 and 300mg/4 weeks in a large European EGPA cohort.

METHODS

We included all EGPA patients treated with mepolizumab at the recruiting centres in 2015-2020. Treatment response was evaluated from month 3 through 24 (T3-T24) after mepolizumab starting. Complete response (CR) was defined as no disease activity (Birmingham Vasculitis Activity Score, BVAS=0) and a prednisone dose ≤4mg/day. Respiratory outcomes included asthma and ear-nose-throat (ENT) exacerbations.

RESULTS

We included 203 patients, of whom 191 at stable dosage (158 mepolizumab 100mg/4 weeks, 33 300mg/4 weeks). At T3, 25 patients (12.3%) had a CR. CR rates increased to 30.4% and 35.7% at T12 and T24 and were comparable between mepolizumab 100 and 300mg/4 weeks. Mepolizumab led to a significant reduction in BVAS, prednisone dose, eosinophil counts from T3 through T24, with no significant differences between 100 and 300 mg/4weeks. Eighty-two patients (40.4%) experienced asthma exacerbations [57/158 (36%) on 100mg/4 weeks; 17/33 (52%) on 300mg/4 weeks]. Thirty-one (15.3%) experienced ENT exacerbations. Forty-four patients (21.7%) experienced adverse events, most being non-serious (38/44).

CONCLUSION

Mepolizumab both at 100 and 300mg/4 weeks is effective for EGPA. The two dosages should be compared in the setting of a controlled trial.

Initiation and Pathogenesis of Severe Asthma with Fungal Sensitization

Fungi represent one of the most diverse and abundant eukaryotes on earth, and their ubiquity and small proteolytically active products make them pervasive allergens that affect humans and other mammals. The immunologic parameters surrounding fungal allergies are still not fully elucidated despite their importance given that a large proportion of severe asthmatics are sensitized to fungal allergens. Herein, we explore fungal allergic asthma with emphasis on mouse models that recapitulate the characteristics of human disease, and the main leukocyte players in the pathogenesis of fungal allergies. The endogenous mycobiome may also contribute to fungal asthma, a phenomenon that we discuss only superficially, as much remains to be discovered.

Biologic Treatments for Asthma and Chronic Obstructive Pulmonary Disorder

The global COVID-19 pandemic has brought respiratory disease to the forefront of public health, but asthma prevalence has been rising globally for decades. Asthma is mediated by errant immune activation and airway remodeling, but the influences of environment, nutrition, and comorbidities (e.g., asthma-chronic obstructive pulmonary disorder-overlap [ACO]) are still poorly understood. Even as a new generation of biologic-based treatments offer better airway control and reductions in mortality, a lack of prophylactic treatments and mechanistic understanding complicates efforts to prevent pathogenesis. This review will explicate and synthesize current knowledge on the effect of ACO and biologics (omalizumab, mepolizumab, reslizumab, benralizumab, and dupilumab) on pathogenesis, treatment, and prognosis.

Results in clinical practice in the treatment of severe eosinophilic asthma with mepolizumab: a real-life study

OBJECTIVE

Add-on therapy with monoclonal antibodies is the recommended therapy for severe asthmatic patients refractory to maintenance treatment. In randomized control trials, mepolizumab reduced the number of exacerbations, the need of oral corticosteroids (OCS), increased asthma control, and lung function in a population of uncontrolled severe eosinophilic asthmatic patients. In this piece of work, we aimed to assess mepolizumab efficacy and safety in a cohort of patients with severe eosinophilic asthma in real-life conditions.

METHODS

A retrospective study was carried out at eight hospitals from Asturias (Spain). The sample included patients treated with mepolizumab from 1 January 2016 to 31 March 2019. Demographic and clinical variables were collected, including OCS use, asthma control, lung function, and exacerbation rate.

RESULTS

Sixty-nine patients (72% women) with mean age 56 ± 13 years were included. Annual exacerbation rate decreased from 4.7 (SD 3.7) to 1.3 (SD 2.5) (p < 0.001). The number of patients requiring OCS treatment decreased from 25 patients (36%, mean prednisone dose = 18 mg/day) to 13 patients (19%, mean prednisone dose = 9 mg/day) (p < 0.001). Twelve patients (48%) stopped OCS treatment. Forced expired volume in one second (FEV1) as percentage increased from 68% (SD 20) to 76% (SD 21) (p < 0.001). Fifty-six patients (81%) were considered responders to mepolizumab. No serious adverse events were detected during the study period.

CONCLUSIONS

Overall, this study demonstrates mepolizumab efficacy and safety in a cohort of patients with uncontrolled severe eosinophilic asthma in routine clinical practice.

Targetable pathogenic mechanisms in nasal polyposis

Chronic rhinosinusitis with nasal polyps (CRSwNP) represents a challenging disease entity with significant rates of recurrence following appropriate medical and surgical therapy. Recent approval of targeted biologics in CRSwNP compels deeper understanding of underlying disease pathophysiology. Both of the approved biologics for CRSwNP modulate the type 2 inflammatory pathway, and the majority of drugs in the clinical trials pathway are similarly targeted. However, there remain multiple other pathogenic mechanisms relevant to CRSwNP for which targeted therapeutics already exist in other inflammatory diseases that have not been studied directly. In this article we summarize pathogenic mechanisms of interest in CRSwNP and discuss the results of ongoing clinical studies of targeted therapeutics in CRSwNP and other related human inflammatory diseases.

A case of allergic bronchopulmonary aspergillosis with marked peripheral blood eosinophilia successfully treated with benralizumab

We herein report a case of allergic bronchopulmonary aspergillosis (ABPA) with marked eosinophilia and high attenuation mucus (HAM) on chest computed tomography (CT), which demonstrated a rapid and remarkable improvement with benralizumab treatment. A 67-year-old Japanese woman, who was diagnosed with asthma at the age of 64 years, was admitted with dyspnea. Her blood test results showed marked eosinophilia (peripheral blood eosinophil count 24403/μL) and elevated serum IgE levels. Chest CT also revealed ground-glass opacity. Sputum cytology detected filamentous fungi, suggesting an infection with Aspergillus spp. Based on these findings, ABPA was diagnosed. Following systemic corticosteroid treatment, her respiratory symptoms and chest radiography findings showed improvements. However, with the gradual tapering and eventual discontinuance of the corticosteroid therapy, a concomitant increase in the peripheral blood eosinophils and a recurrence of the clinical symptoms, was observed. In addition, her pulmonary function decreased and chest CT revealed worsened bronchial mucus plugs. To control the asthma with ABPA exacerbation, benralizumab was administered. Following treatment with benralizumab, the patient's asthmatic symptoms improved, together with a decrease in her peripheral eosinophil count. Mucus plugs were no longer visible on chest CT. Pulmonary function test result also showed a remarkable improvement. There was no relapse of dyspnea and no reappearance of the mucus plugs. This case suggests that benralizumab may be a suitable treatment option for patients with ABPA with marked eosinophilia and HAM on chest CT.

Biologics for the Treatment of Allergic Conditions: Eosinophil Disorders

Eosinophil-associated diseases are characterized by a common pathogenetic background, represented by eosinophil-led inflammation and overexpression of interleukin (IL)-5. IL-5 and its receptor are excellent therapeutic targets for eosinophil-associated diseases. Three monoclonal antibodies targeting IL-5 currently are available: mepolizumab and reslizumab block circulating IL-5 preventing the binding to its receptor, whereas benralizumab binds to IL-5 receptor α. They have a steroid-sparing effect in eosinophil disorders, such as eosinophilic granulomatosis with polyangiitis, hypereosinophilic syndrome, allergic bronchopulmonary aspergillosis, eosinophilic esophagitis, and chronic eosinophilic pneumonia. The biotechnological drugs targeting IL-5 are promising therapies; however, further studies are needed.

Anti-IL5 Therapies for Severe Eosinophilic Asthma: Literature Review and Practical Insights

Severe refractory asthma (SRA) still has a high economic and social impact, including a reduction in quality of life (QoL), productivity, a greater risk of exacerbations and emergency department (ED) visits. Another major issue is the need of oral corticosteroids (OCS), often due to a poor response to standard therapies or the lack of indication for currently available biological drugs. A thorough understanding of the immunological pathways and eosinophilopoietic processes allows a correct application of the new pharmacological strategies and leads to better clinical responses. For these unmet needs, several monoclonal antibody (mAb) drugs have been introduced over the past few years. These are mainly available for allergic and especially eosinophilic uncontrolled refractory asthma. As the number of therapeutic options increases, the choice of biological drugs can be made only after careful considerations of the particular asthma endotype, patients’ comorbidities and clinical data. The selection of the correct therapeutic option can therefore be guided after a careful evaluation of the particular endotype and phenotype, from the combined evaluation of inflammatory biomarkers, clinical picture and comorbidities. The careful evaluation of all these parameters can therefore help the physician in the optimal management of these complex patients, for whom it is often possible to achieve exceptional results by managing the available options in the best possible way. The aim of this review is to define the positioning of the biological drugs currently available for type 2 asthma, with a special focus on options for eosinophilic asthma in the context of the most recent knowledge of immunological pathways.