Interleukin-5 in the Pathophysiology of Severe Asthma

Interleukin-5 (IL-5) exerts a central pathogenic role in differentiation, recruitment, survival, and degranulation of eosinophils. Indeed, during the last years, significant advances have been made in our understanding of the cellular and molecular mechanisms underlying the powerful actions of IL-5 finalized to the induction, maintenance, and amplification of eosinophilic inflammation. Therefore, IL-5 is a suitable target for add-on biological therapies based on either IL-5 inhibition (mepolizumab, reslizumab) or blockade of its receptor (benralizumab). These modern treatments can result in being definitely beneficial for patients with severe type 2 (T2)-high eosinophilic asthma, refractory to conventional anti-inflammatory drugs such as inhaled and even systemic corticosteroids.

Omalizumab, the first available antibody for biological treatment of severe asthma: more than a decade of real-life effectiveness

Omalizumab was the first, and for a long time the only available monoclonal antibody for the add-on treatment of severe allergic asthma. In particular, omalizumab selectively targets human immunoglobulin (Ig)E, forming small-size immune complexes that inhibit IgE binding to its high- and low-affinity receptors. Therefore, omalizumab effectively blunts the immune response in atopic asthmatic patients, thus significantly improving the control of asthma symptoms and successfully preventing disease exacerbations. These very positive effects of omalizumab make it possible to drastically decrease both referrals to the emergency room and hospitalizations for asthma exacerbations. Such important therapeutic actions of omalizumab have been documented by several randomized clinical trials, and especially by more than 10 years of real-life experience in daily clinical practice. Omalizumab can also interfere with airway remodelling by inhibiting the activation of IgE receptors located on structural cells such as bronchial epithelial cells and airway smooth muscle cells. Moreover, omalizumab is characterized by a very good safety and tolerability profile. Hence, omalizumab represents a valuable therapeutic option for the add-on biological treatment of severe allergic asthma.

Benralizumab: From the Basic Mechanism of Action to the Potential Use in the Biological Therapy of Severe Eosinophilic Asthma

Asthma is a very frequent chronic airway disease that includes many different clinical phenotypes and inflammatory patterns. In particular, eosinophilic bronchial inflammation is often associated with allergic as well as nonallergic asthma. The most important cytokine involved in the induction, maintenance, and amplification of airway eosinophilia in asthma is interleukin-5 (IL-5), released by both T helper 2 (Th2) lymphocytes and group 2 innate lymphoid cells (ILC2). Hence, IL-5 and its receptor are suitable targets for selective biologic drugs which can play a key role in add-on treatment of severe eosinophilic asthma refractory to corticosteroids. Within such a context, the anti-IL-5 monoclonal antibodies mepolizumab and reslizumab have been developed and approved for biological therapy of uncontrolled eosinophilic asthma. In this regard, on the basis of several successful randomized controlled trials, the anti-IL-5 receptor benralizumab has also recently obtained the approval from US Food and Drug Administration (FDA).

Lung under attack by COVID-19-induced cytokine storm: pathogenic mechanisms and therapeutic implications

The lung is a key target of the cytokine storm that can be triggered by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2), responsible for the widespread clinical syndrome known as coronavirus disease 2019 (COVID-19). Indeed, in some patients, SARS-CoV-2 promotes a dysfunctional immune response that dysregulates the cytokine secretory pattern. Hypercytokinemia underlies the hyperinflammatory state leading to injury of alveolar epithelial cells and vascular endothelial cells, as well as to lung infiltration sustained by neutrophils and macrophages. Within such a pathogenic context, interleukin-6 (IL-6) and other cytokines/chemokines play a pivotal pro-inflammatory role. Therefore, cytokines and their receptors, as well as cytokine-dependent intracellular signalling pathways can be targeted by potential therapies aimed to relieve the heavy burden of cytokine storm. In particular, the anti-IL-6-receptor monoclonal antibody tocilizumab is emerging as one of the most promising pharmacologic treatments. The reviews of this paper are available via the supplemental material section.

Molecular Targets for Biological Therapies of Severe Asthma

Asthma is a heterogeneous respiratory disease characterized by usually reversible bronchial obstruction, which is clinically expressed by different phenotypes driven by complex pathobiological mechanisms (endotypes). Within this context, during the last years several molecular effectors and signalling pathways have emerged as suitable targets for biological therapies of severe asthma, refractory to standard treatments. Indeed, various therapeutic antibodies currently allow to intercept at different levels the chain of pathogenic events leading to type 2 (T2) airway inflammation. In addition to pro-allergic immunoglobulin E (IgE), that chronologically represents the first molecule against which an anti-asthma monoclonal antibody (omalizumab) was developed, today other targets are successfully exploited by biological treatments of severe asthma. In particular, pro-eosinophilic interleukin 5 (IL-5) can be targeted by mepolizumab or reslizumab, whereas benralizumab is a selective blocker of IL-5 receptor. Moreover, dupilumab behaves as a dual receptor antagonist of pleiotropic interleukins 4 (IL-4) and 13 (IL-13). Besides these drugs that are already available in medical practice, other biologics are under clinical development such as those targeting innate cytokines, also including the alarmin thymic stromal lymphopoietin (TSLP), which plays a key role in the pathogenesis of type 2 asthma. Therefore, ongoing and future biological therapies are significantly changing the global scenario of severe asthma management. These new therapeutic options make it possible to implement phenotype/endotype-specific treatments, that are delineating personalized approaches precisely addressing the individual traits of asthma pathobiology. Such tailored strategies are thus allowing to successfully target the immune-inflammatory responses underlying uncontrolled T2-high asthma.

Severe eosinophilic asthma: from the pathogenic role of interleukin-5 to the therapeutic action of mepolizumab

Mepolizumab is an anti-interleukin-5 (IL-5) humanized monoclonal antibody that has been recently approved as an add-on biological treatment for severe eosinophilic asthma, by both the US Food and Drug Administration (FDA) and the European Medicines Agency (EMA). Moreover, mepolizumab is also currently included within the step 5 of the Global Initiative for Asthma guidelines, as an add-on therapy for severe uncontrolled asthma. The relevant therapeutic benefits detectable in patients with refractory eosinophilic asthma receiving mepolizumab depend on the pivotal pathogenic role played by IL-5 in these subjects. Indeed, IL-5 is the key cytokine responsible for maturation, activation, proliferation, and survival of eosinophils. Therefore, IL-5 represents a strategic molecular target for anti-eosinophilic treatments. By selectively inhibiting the biological actions of IL-5, mepolizumab provides a valuable therapeutic option for patients with severe eosinophilic asthma, refractory to standard treatments including inhaled and even systemic corticosteroids. In particular, the very important advantages linked to the use of mepolizumab in these difficult-to-treat asthmatic individuals have been well documented by several different trials performed worldwide.

Interleukins 4 and 13 in Asthma: Key Pathophysiologic Cytokines and Druggable Molecular Targets

Interleukins (IL)-4 and -13 play a pivotal role in the pathobiology of type-2 asthma. Indeed, IL-4 is crucially involved in Th2 cell differentiation, immunoglobulin (Ig) class switching and eosinophil trafficking. IL-13 cooperates with IL-4 in promoting IgE synthesis, and also induces nitric oxide (NO) production, goblet cell metaplasia and fibroblast proliferation, as well as elicits contractile responses and hyperplasia of airway smooth muscle cells.

IL-4 and IL-13 share common signaling pathways, activated by the binding of both cytokines to receptor complexes including the α-subunit of the IL-4 receptor (IL-4Rα). Therefore, the subsequent receptor dimerization is responsible for the pathophysiologic effects of IL-4 and IL-13. By selectively blocking IL-4Rα, the fully human IgG4 monoclonal antibody dupilumab behaves as a dual receptor antagonist of both IL-4 and IL-13. Through this mechanism of action, dupilumab exerts effective therapeutic actions in type-2 inflammation, thus decreasing asthma exacerbations, FeNO (fractional exhaled NO) levels, and the intake of oral corticosteroids (OCS). In addition to being approved for the add-on biological therapy of severe asthma, dupilumab has also been licensed for the treatment of nasal polyposis and atopic dermatitis.

Real-life evaluation of mepolizumab efficacy in patients with severe eosinophilic asthma, according to atopic trait and allergic phenotype

BACKGROUND

Anti-interleukin-5 (IL-5) monoclonal antibodies can be used as add-on biological therapies in allergic and non-allergic patients with severe eosinophilic asthma. However, within such a therapeutic context real-life investigations are lacking.

OBJECTIVE

Therefore, the aim of the present observational study was to evaluate the effects of mepolizumab in allergic and non-allergic subjects with severe eosinophilic asthma.

METHODS

Relevant clinical, functional, laboratory, and pharmacotherapeutic parameters were assessed in the above patient subgroups.

RESULTS

After one year of add-on biological treatment with mepolizumab, our 88 patients experienced a remarkable improvement of their severe asthma, documented by a better symptom control, expressed by a significant improvement in asthma control test (ACT) score. Indeed, the mean value (±standard deviation) of ACT score increased from 12.55 (±3.724) to 21.08 (±3.358). Moreover, significant improvements were also detected with regard to the median values (interquartile range) of forced expiratory volume in one second (FEV₁ ), blood eosinophil numbers, annual rate of disease exacerbations, and daily intake of oral corticosteroids (OCS). In particular, FEV₁ enhanced from 1640 mL (1110-2275) to 1920 mL (1525-2615), blood eosinophil count dropped from 711.0 cells/μL (500.0-1022) to 90.00 cells/μL (50.00-117.5), the annual rate of asthma exacerbations decreased from 3.000 (2.000-6.000) to 0.000 (0.000-1.000), and the daily prednisone intake fell from 6.250 mg (0.000-25.00) to 0.000 mg (0.000-0.000). After one year of mepolizumab treatment, the improvements in clinical, functional, and haematological parameters were quite similar in patient subgroups characterized by skin prick test (SPT) negativity or positivity, respectively. A significant correlation was observed between serum IgE levels and OCS intake decrease (r = -0.2257; P < .05).

CONCLUSION AND CLINICAL RELEVANCE

Hence, our real-life data suggest that mepolizumab can represent a valid add-on therapeutic option for patients with severe eosinophilic asthma, irrespective of IgE serum concentrations, and allergic sensitization.

Benralizumab Effectiveness in Severe Eosinophilic Asthma with and without Chronic Rhinosinusitis with Nasal Polyps: A Real-World Multicenter Study

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) affects around 60% of patients with severe eosinophilic asthma (SEA). Benralizumab was recently approved for SEA add-on treatment.

OBJECTIVE

To assess the real-world effectiveness of benralizumab in SEA with or without CRSwNP.

METHODS

We conducted a multicenter observational study, including patients with SEA treated with benralizumab for 24 weeks in 12 Italian specialized facilities. Asthma exacerbations, Asthma Control Test (ACT), lung function, oral corticosteroid (OCS) dosage, and eosinophil and basophil count in peripheral blood were recorded at baseline and after 4, 12, and 24 weeks. The 22-item Sino-Nasal Outcome Test (SNOT-22) and Lund-Mackay scores were assessed at baseline and after 24 weeks in SEA+CRSwNP.

RESULTS

A total of 137 patients with late-onset SEA were included; 57.7% (79 of 137) showed the copresence of CRSwNP. Overall, severe asthma exacerbations decreased from 4 (3-6) to 0 (0-2) (P < .0001) after 24 weeks of treatment, and significant improvements were observed as early as 4 weeks in ACT score, OCS dosage, forced expiratory volume in the 1st second (FEV₁)%, FEV₁ (L), forced vital capacity (FVC)%, FEV₁/FVC% (P < .0001), and forced expiratory flow between 25% and 75% of FVC (FEF_25-75)% (P = .0022). Eosinophils and basophils in peripheral blood were rapidly depleted. In patients with SEA+CRSwNP, SNOT-22 decreased from 46 (39.5-64.5) to 32 (19-46) (P < .0001). Furthermore, in comparison with SEA, they showed enhanced responses with regard to ACT minimal clinically important difference (P = .0387), FEV₁% (P = .017), FEV₁ (L) (P = .02), and FEF_25-75% (P = .0362).

CONCLUSIONS

These real-world data suggest that benralizumab can represent a valid add-on therapeutic option for patients with SEA, especially with comorbid CRSwNP.

Benralizumab in the treatment of severe asthma: design, development and potential place in therapy

Asthma is a widespread and heterogeneous inflammatory disease of the airways, which is characterized by several different phenotypes and endotypes. In particular, eosinophilic airway inflammation is a common pathologic trait of both allergic and nonallergic asthma. The key cytokine responsible for maturation, activation, recruitment, and survival of eosinophils is interleukin (IL)-5, which is mainly produced by T helper 2 (Th2) lymphocytes and group 2 innate lymphoid cells. Therefore, for uncontrolled patients with severe eosinophilic asthma, who are not fully responsive to corticosteroids, IL-5 represents a very important molecular target for add-on biological therapies. Among these new treatments, anti-IL-5 monoclonal antibodies such as mepolizumab and reslizumab have been developed and clinically evaluated. Furthermore, benralizumab is currently the only available biologic drug that specifically binds to the IL-5 receptor, thus preventing the interaction with its ligand and the consequent pro-inflammatory effects. The effectiveness of benralizumab in improving severe eosinophilic asthma has been well-documented by many randomized controlled trials.

Therapeutic Effects of Benralizumab Assessed in Patients with Severe Eosinophilic Asthma: Real-Life Evaluation Correlated with Allergic and Non-Allergic Phenotype Expression

BACKGROUND

Benralizumab can be utilized as add-on biological treatment of severe eosinophilic asthma. However, so far only a few real-life studies have been published with regard to the use of this anti-IL-5 receptor humanized monoclonal antibody.

OBJECTIVE

The primary aim of this multicenter observational investigation has been to assess the therapeutic effects of benralizumab in patients with severe uncontrolled, corticosteroid refractory eosinophilic asthma. The secondary objective was to evaluate the efficacy of benralizumab with regard to positive or negative skin prick test (SPT).

METHODS

Clinical, functional, and laboratory parameters were evaluated in order to verify the therapeutic actions of benralizumab in atopic and non atopic subjects with difficult-to-treat eosinophilic asthma. Moreover, a comparative evaluation was carried out in relation to the presence or absence of SPT positivity.

RESULTS

After 6 months of add-on biological therapy with benralizumab, our 111 patients experienced a marked improvement of their severe eosinophilic asthma, expressed by significant changes in asthma exacerbation rate, prednisone intake, daily use of short-acting β2-adrenergic agonists (SABA), asthma control test (ACT) score, asthma quality of life questionnaire (AQLQ) score (56 patients), forced expiratory volume in one second (FEV1), forced vital capacity (FVC), blood eosinophil count, blood basophil count (59 patients), and fractional exhaled nitric oxide (FeNO) levels (39 patients). In addition, significantly more effective outcomes were detected in patients with positive SPT, when compared to subjects with negative SPT, only in regard to asthma exacerbation number, ACT score, and daily SABA utilization. No significant correlation was found between serum IgE concentrations and each of all measured parameters.

CONCLUSION AND CLINICAL RELEVANCE

Taken together, the results of this real-world study indicate that in both allergic and non-allergic subjects benralizumab can be used as a valuable pharmacotherapeutic option for add-on biological therapy of severe eosinophilic asthma, regardless of SPT positivity or negativity.

Mepolizumab effectiveness on small airway obstruction, corticosteroid sparing and maintenance therapy step-down in real life

BACKGROUND

Mepolizumab (MEP) has been recently introduced to treat severe eosinophilic asthma. Trials have demonstrated a significant effectiveness in this asthma phenotype. We evaluated MEP efficacy on lung function, symptoms, asthma exacerbations, biologic markers, steroid dependence and controller treatment level in real-life.

METHODS

We retrospectively analyzed 134 severe asthmatics (61 males; mean age 58.3 ± 11; mean FEV₁%:72 ± 21), treated with MEP for at least 6 months (mean duration:10.9 ± 3.7 months).

RESULTS

FEV₁% improved significantly after MEP. Mean FEF_25-75 also increased from 37.4 ± 25.4% to 47.2 ± 27.2% (p < 0.0001). Mean baseline blood eosinophil level was 712 ± 731/μL (8.4 ± 5.2%) decreasing to 151 ± 384/μL (1.6 ± 1.6%) (p < 0.0001), FENO levels decreased likewise. MEP treatment also led to a significant ACT improvement (mean pre:14.2 ± 4.4; mean post:20.5 ± 28) and exacerbations significantly fell from 3.8 ± 1.9 to 0.8 ± 1.1 (p < 0.0001). 74% of patients were steroid-dependent before MEP. 45.4% and 46.4% of them showed a suspension and dose reduction respectively (p < 0.0001). A significant number reduced also ICS doses. Only 67% of subjects used SABA as needed before MEP, falling to 20% after MEP. About 40% of patients highlighted a maintenance therapy step-down. Subjects showing an omalizumab treatment failure before MEP had a similar positive response when compared with omalizumab untreated patients.

CONCLUSION

In real-life, MEP improved significantly all outcomes even small airway obstruction, suggesting its possible role also in distal lung region treatment. Furthermore, it demonstrated its high effectiveness in OC/ICS-sparing, in reducing SABA as needed and in stepping-down maintenance therapy. MEP is a valid alternative for patients with previous omalizumab treatment failure.

Real-life rapidity of benralizumab effects in patients with severe allergic eosinophilic asthma: Assessment of blood eosinophils, symptom control, lung function and oral corticosteroid intake after the first drug dose

Benralizumab is a humanized monoclonal antibody which binds to the α subunit of the interleukin-5 (IL-5) receptor and to the FcγRIIIa receptor expressed by natural killer cells, thus suppressing the pro-eosinophil actions of IL-5 and triggering eosinophil apoptosis via the very effective mechanism of antibody-dependent cell-mediated cytotoxicity (ADCC). Because of its recent approval and introduction in clinical practice for the add-on biological therapy of severe eosinophilic asthma, real-life investigations are still lacking. In this regard, our present real-life study refers to 13 patients with severe allergic eosinophilic asthma, currently under treatment with benralizumab at the Respiratory Unit of "Magna Græcia" University Hospital located in Catanzaro, Italy. Already 4 weeks after the first subcutaneous injection of benralizumab at the dosage of 30 mg, blood eosinophil count rapidly dropped down from 814.7 ± 292.3 cells/μL to 51.3 ± 97.5 cells/μL (p < 0.0001). This relevant hematologic change was associated with quick and significant increases in asthma control test (ACT) score (from 15.31 ± 2.78 to 21.15 ± 3.58; p < 0.0001), pre-bronchodilator forced expiratory volume in 1 s (FEV₁) (from 1441 ± 757.9 mL to 1887 ± 837.3 mL; p < 0.001), and morning peak expiratory flow (PEF) (from 4.21 ± 2.20 to 5.33 ± 1.99 L/sec; p < 0.01). Furthermore, the marked improvement in global health status experienced by our patients allowed them to progressively lower and then completely interrupt, within 4 weeks, their daily intake of oral corticosteroids (OCS), which thereby fell from 15.58 ± 8.30 to 0 mg (p < 0.0001) of prednisone. Therefore, such preliminary results suggest that in patients with severe allergic eosinophilic asthma benralizumab can exert, within a real-life context, a very rapid and effective therapeutic action, already detectable 4 weeks after the first drug administration.

Real-life effects of benralizumab on allergic chronic rhinosinusitis and nasal polyposis associated with severe asthma

The aim of this study has been to evaluate the efficacy of the IL-5 receptor blocker benralizumab on chronic rhinosinusitis with nasal polyposis (CRSwNP), associated with severe eosinophilic allergic asthma. Ten patients with severe eosinophilic allergic asthma and CRSwNP were enrolled. Sino-nasal outcome test (SNOT-22), numerical rating scale (NRS), endoscopic nasal polyp score, Lund Mackey CT (computed tomography) score, and blood eosinophil count were measured at baseline and after 24 weeks of treatment with benralizumab. All the above clinical, endoscopic, imaging, and hematological parameters significantly improved after 24 weeks of treatment with benralizumab. In particular, SNOT-22 decreased from 61.10 ± 17.20 to 26.30 ± 19.74 (P < 0.001), NRS decreased from 7.20 ± 1.55 to 3.40 ± 2.22 (P < 0.001), the endoscopic polyp nasal score decreased from 4.20 ± 1.32 to 2.50 ± 1.78 (P < 0.001), the Lund-Mackay CT score decreased from 16.60 ± 5.50 to 6.90 ± 5.99 (P < 0.001), and blood eosinophil count decreased from 807.3 ± 271.1 cells/μL to 0 cells/μL (P < 0.0001). These results strongly suggest that benralizumab exerted a very effective therapeutic action on CRSwNP associated with severe asthma, thus improving nasal symptoms and decreasing polyp size.

Tezepelumab: A Potential New Biological Therapy for Severe Refractory Asthma

Thymic stromal lymphopoietin (TSLP) is an innate cytokine, belonging to the group of alarmins, which plays a key pathogenic role in asthma by acting as an upstream activator of cellular and molecular pathways leading to type 2 (T2-high) airway inflammation. Released from airway epithelial cells upon tissue damage induced by several noxious agents including allergens, viruses, bacteria, and airborne pollutants, TSLP activates dendritic cells and group 2 innate lymphoid cells involved in the pathobiology of T2-high asthma. Tezepelumab is a fully human monoclonal antibody that binds to TSLP, thereby preventing its interaction with the TSLP receptor complex. Preliminary results of randomized clinical trials suggest that tezepelumab is characterized by a good safety and efficacy profile in patients with severe, uncontrolled asthma.

Real-life evaluation of the clinical, functional, and hematological effects of mepolizumab in patients with severe eosinophilic asthma: Results of a single-centre observational study

Mepolizumab is a humanized monoclonal antibody which targets interleukin-5 (IL-5) and is nowadays available in many countries for add-on biological therapy of severe eosinophilic asthma. Although the approval of mepolizumab use in clinical practice has been made possible by several successful pre-marketing controlled trials, so far only a very few studies have been performed in a real-life setting. Within such a context, our present observational investigation refers to 14 patients with refractory eosinophilic asthma, currently treated with mepolizumab at the Respiratory Unit of "Magna Græcia" University Hospital located in Catanzaro, Italy, whose anti-IL-5 treatment began between June 2017 and January 2018. These patients experienced a significant increase in asthma control test (ACT) score, that was evaluated at baseline (13.64 ± 3.00), as well as after 4 weeks (18.86 ± 3.15; p < 0.0001) and 24 weeks (20.07 ± 1.94; p < 0.0001) of add-on therapy with mepolizumab. This relevant improvement in symptom control was paralleled by a dramatic fall of blood eosinophil numbers, counted at baseline (647.1 ± 274.7 cells/μl), and at the 4th (147.8 ± 66.5 cells/μl; p < 0.0001) and 24th week (98.6 ± 40.3 cells/μl; p < 0.0001) after starting add-on treatment with mepolizumab. These changes were associated with significant and stable increases in FEV₁, which was recorded at baseline (1389 ± 454.3 mL), as well as after 4 weeks (1711 ± 482.3 mL; p < 0.001) and 24 weeks (1701 ± 456.0 mL; p < 0.01). Moreover, in comparison to the 6 months preceding the beginning of treatment with mepolizumab, after 24 weeks of anti-IL-5 therapy significant decreases were detected with regard to exacerbation numbers (from 3.64 ± 1.86 to 1.0 ± 0.78; p < 0.001) and oral intake of prednisone (from 24.11 ± 10.36 mg/day to 1.78 ± 3.82 mg/day). Therefore, these preliminary data referring to our single-centre observational study corroborate, in a real-life environment, the efficacy of mepolizumab for treatment of patients with exacerbation-prone, corticosteroid-refractory, severe eosinophilic asthma.

Switching from omalizumab to mepolizumab: real-life experience from Southern Italy

BACKGROUND

Current availability of several biologic treatments for severe asthma makes it possible to choose the most appropriate for each patient. Sometimes a good percentage of patients with severe asthma may be eligible for biologics that target either the allergic phenotype or the eosinophilic one, but not all respond to that selected as first choice. The aim of our real-life study was to assess whether, for patients with severe eosinophilic allergic asthma, not previously controlled by the anti-IgE omalizumab, the shift to another biologic targeting interleukin-5, such as mepolizumab, may represent a good therapeutic choice.

METHODS

A total of 41 consecutive patients with severe, persistent allergic, eosinophilic asthma, uncontrolled despite treatment with omalizumab, were enrolled in seven certified Clinical Respiratory Units of Southern Italy (Catania, Catanzaro, Foggia, Bari, Palermo, and two University Respiratory Units of Naples) and shifted to mepolizumab without a wash-out period. Data at baseline, after at least 12 months of therapy with omalizumab, and after at least 12 months of treatment with mepolizumab were collected.

RESULTS

After at least 12 months of therapy with mepolizumab, patients experienced a significant decrease in the number of exacerbations/year (5.8 ± 1.8 versus 0.7 ± 0.9, p < 0.0001), an increment of asthma control test score (12 ± 2.7 versus 21.9 ± 2.7, p < 0.0001), an increase in pre-bronchodilator forced expiratory volume in 1 s (1.56 ± 0.45 l versus 1.86 ± 0.52 l, p < 0.0001), and a reduction of blood eosinophils (584 ± 196 cells/µl versus 82 ± 56 cells/µl, p < 0.0001). The percentage of patients who were dependent on corticosteroids significantly decreased from 46% at baseline to 5% during treatment with mepolizumab.

CONCLUSION

Results of our real-life multicentric experience confirms that the shift to mepolizumab could be a good therapeutic strategy in severe eosinophilic allergic asthma not previously controlled by omalizumab. The reviews of this paper are available via the supplemental material section.

Real-life effectiveness of mepolizumab in patients with severe refractory eosinophilic asthma and multiple comorbidities

Background

Data on mepolizumab in patients with severe eosinophilic asthma (EA) and comorbidities are needed to assess whether randomized controlled trial results are applicable in the real world.

Objective

To evaluate real-life effectiveness and the presence/absence of predictors of treatment response in patients with one or more comorbidities (nasal polyps, allergic rhinitis, gastro-esophageal reflux disease, nonallergic rhinitis with eosinophilia syndrome, obesity, bronchiectasis) who received mepolizumab (MEPO) for the treatment of severe EA.

Methods

We performed a single-center retrospective study in patients with severe asthma and presence of comorbidities treated with mepolizumab at the respiratory outpatient clinic, Policlinico-Vittorio Emanuele, Catania, Italy. Health records of 31 severe asthmatic patients were retrieved and analyzed. Asthma control test (ACT) score, blood eosinophil count, forced expiratory volume in 1 s (FEV₁), FEV₁% of predicted and FEV₁/FVC (Forced Vital Capacity) ratio, oral corticosteroid (OCS) dosage, and exacerbations were recorded at baseline (T0), after 3 (T1), 6 (T3), 9 (T6), and 12 months (T12). Clinical response was defined when 3 of these 4 criteria were fulfilled: i) 30% exacerbation decrease; ii) 80% blood eosinophilia reduction; iii) 3 point ACT increase; iv) FEV₁ increase ≥200 mL.

Results

83.87% of patients were classified as responsive to MEPO treatment. Substantial depletion of the blood eosinophils (>80%) was found in 87.1% of patients, FEV₁ > 200 mL was seen in 54.84% of patients, a 3-point ACT improvement from baseline was recorded in 80.65% 25 of patients and a 30% reduction of exacerbations rates was seen in 96.77% of patients. Moreover, the majority 38.71% of patients met 3/4 parameters after 12 months. Neither the comorbidities nor other characteristics (sex, BMI, age, smoking) influenced treatment response.

Conclusions

MEPO in patients with severe EA is effective regardless of the presence of comorbidities.

Patient-ventilator asynchrony in adult critically ill patients

INTRODUCTION

Patient-ventilator asynchrony is considered a major clinical problem for mechanically ventilated patients. It occurs during partial ventilatory support, when the respiratory muscles and the ventilator interact to contribute generating the volume output. In this review article, we consider all studies published on patient-ventilator asynchrony in the last 25 years.

EVIDENCE ACQUISITION

We selected 62 studies. The different forms of asynchrony are first defined and classified. We also describe the methods used for detecting and quantifying asynchronies. We then outline the outcome variables considered for evaluating the clinical consequences of asynchronies. The methodology for detection and quantification of patient-ventilator asynchrony are quite heterogeneous. In particular, the Asynchrony Index is calculated differently among studies.

EVIDENCE SYNTHESIS

Sixteen studies established some relationship between asynchronies and one or more clinical outcomes, such as duration of mechanical ventilation (seven studies), mortality (five studies), length of intensive care and hospital stay (four studies), patient comfort (four studies), quality of sleep (three studies), and rate of tracheotomy (three studies). In patients with severe patient-ventilator asynchrony, four of seven studies (57%) report prolonged duration of mechanical ventilation, one of five (20%) increased mortality, one of four (25%) longer intensive care and hospital lengths of stay, four of four (100%) worsened comfort, three of four (75%) deteriorated quality of sleep, and one of three (33%) increased rate of tracheotomy.

CONCLUSIONS

Given the varying outcomes considered and the erratic results, it remains unclear whether asynchronies really affects patient outcome, and the relationship between asynchronies and outcome is causative or associative.

Short-Term Evaluation of Dupilumab Effects in Patients with Severe Asthma and Nasal Polyposis

Background

Having been approved for biological treatment of atopic dermatitis, dupilumab has also been recently licensed as add-on therapy for severe asthma and nasal polyposis. With regard to the latter diseases, few real-life clinical investigations have been carried out to date.

Objective

The primary end point of this single-center observational study was to evaluate in a real-life setting the short-term therapeutic effects of dupilumab in patients with severe asthma and nasal polyposis.

Methods

At baseline and after 4 weeks of add-on therapy with dupilumab, several clinical and functional parameters were assessed in 20 patients with severe asthma and nasal polyposis, including both allergic and nonallergic subjects.

Results

After 4 weeks of treatment with dupilumab, all patients experienced remarkable improvement in both severe asthma and nasal polyposis. In particular, asthma-control test and sinonasal outcome test 22 scores had significantly increased (p<0.0001) and decreased (p<0.0001), respectively. Oral corticosteroid intake got to zero within 4 weeks (p<0.0001). Moreover, in week 4, significant increases were detected with regard to both prebronchodilator forced expiratory volume in the first second (p<0.01) and forced vital capacity (FVC; p<0.05). At the same time point, dupilumab had significantly reduced residual volume (p<0.0001) and total lung capacity (p<0.001), whereas it had enhanced forced midexpiratory flow of 25%–75% FVC (p<0.01) and peak expiratory flow (p<0.01). After 4 weeks of treatment, dupilumab had also lowered levels of fractional exhaled nitric oxide (p<0.0001).

Conclusion

The results of this real-life study suggest that dupilumab can be utilized in both allergic and nonallergic patients with severe asthma and nasal polyposis as a valuable add-on biological therapy with rapid onset of action.

Uric Acid and Vascular Damage in Essential Hypertension: Role of Insulin Resistance

Increased levels of uric acid (UA) have been shown to be correlated with many clinical conditions. Uric acid may adversely affect the insulin signalling pathway inducing insulin resistance (IR). Several studies report the association between arterial stiffness (AS), an early indicator of atherosclerosis, and UA. The purpose of the present study was to evaluate the association between UA and AS, considering the potential role of IR. We enrolled 1114 newly diagnosed, never-treated hypertensive patients. Insulin resistance was assessed by the homeostatic model assessment (HOMA) index. Arterial stiffness was evaluated as the measurement of the carotid-femoral pulse wave velocity (PWV). The study cohort was divided into subgroups, according to increasing tertiles of UA. The mean values of UA were 5.2 ± 1.6 mg/dL in the overall population. Pulse wave velocity was linearly correlated with UA (p < 0.0001), HOMA (p < 0.0001), high sensitivity C-reactive protein (p < 0.0001), systolic blood pressure (p < 0.0001) and LDL cholesterol (p = 0.005). Uric acid was the strongest predictor of PWV and was associated with the highest risk for increased AS. The interaction analysis showed that the joint effect of increased UA and HOMA was significantly higher than that expected in the absence of interaction under the additive model, indicating that the two biomarkers synergically interacted for promoting vascular damage. Our data showed that UA interacted with IR to increase AS in a large cohort of newly diagnosed, never-treated hypertensive patients.

Comparisons of two diaphragm ultrasound-teaching programs: a multicenter randomized controlled educational study

Background

This study aims to ascertain whether (1) an educational program is sufficient to achieve adequate Diaphragm Ultrasound (DUS) assessments on healthy volunteers and (2) combining a video tutorial with a practical session is more effective in making learners capable to obtain accurate DUS measurements, as opposed to sole video tutorial.

Results

We enrolledstep 1: 172 volunteers naïve to ultrasound. After watching a video tutorial, a questionnaire was administered and considered to be passed when at least 70% of the questions were correctly answered. Course participants who passed the theoretical test were randomized to either intervention or control group. Learners randomized to the interventional group underwent to a practical training, tutored by an expert, before accessing DUS examination. Participants randomized to the control group directly accessed DUS examination, without any practical training. DUS measurements by learners and tutors were recorded and checked for accuracy, according to predefined criteria. Detection of both acoustic windows and accurate DUS assessment was achieved by 83.7% learners of the intervention group while 3.5% only among controls (p < 0.0001). The subcostal view of the diaphragm was correctly identified by 92% and 65% learners in the intervention and control groups, respectively (p < 0.0001) while the apposition zone by 86% and 71% learners, respectively (p = 0.026). An accurate diaphragm displacement (DD) measurement was obtained by 91% and 45% learners in the intervention and control groups, respectively (p < 0.0001) while an accurate thickening fraction (TF) measurement by 99% and 21%, respectively (p < 0.0001). DD measurements by both groups of learners were significantly correlated with those assessed by expert tutors; however, a significant improvement of measurement accuracy was found in learners randomized to receive also the practical training, compared to controls.

Conclusions

A combined approach consisting of a theoretical module followed by a practical training is more effective in managing acoustic windows and performing accurate measurements when compared to an exclusively theoretical course.

Trial registration prospectively registered on clinicaltrials.gov (Identifier: NCT03704129; release date 17th October 2018).

High-flow nasal cannula oxygen therapy for outpatients undergoing flexible bronchoscopy: a randomised controlled trial

INTRODUCTION

High-flow nasal cannula (HFNC) provides benefits to patients undergoing flexible bronchoscopy (FOB). We compared the effects of HFNC versus standard therapy (ST) on gas exchange, lung volume and diaphragm function in patients undergoing FOB for bronchoalveolar lavage (BAL).

METHODS

36 outpatients were randomised to ST or HFNC. Arterial blood gases, episodes of severe desaturation, changes of end-expiratory lung impedance (ΔEELI), diaphragm ultrasound were recorded. Measurements were done at baseline (T0), after bronchoscope insertion (T1), at the end of the procedure (T2) and 10 min afterwards (T3).

RESULTS

Arterial partial oxygen pressure (PaO₂) was not different between T0 (10.8 (95% CI 8.7 to 12.0) kPa and T2 (11.1 (95% CI 10.4 to 12.0) kPa) with HFNC, while decreased from 11.1 (95% CI 10.5 to 12.1) to 9.1 (95% CI 8.4 to 9.8) kPa with ST. At T2, PaO₂ was significantly higher with HFNC than with ST (p<0.001). Also, with HFNC, compared with ST, fewer desaturations occurred (11% vs 56%; p<0.01). ΔEELI was no different at the different time points with HFNC, while with ST there was a significant decrease at T1 (-170 (95% CI -382 to -32) mL, p=0.003), T2 (-211 (95% CI -425 to -148) mL, p<0.001) and T3 (-213 (95% CI -398 to -81) mL, p<0.001), as opposed to T0. EELI was lower with ST than HFNC at T1 (p=0.006), T2 (p=0.001) and T3 (p=0.002). Diaphragm displacement was no different between groups (p=0.748), while the thickening fraction significantly increased at T1 and T2 with ST only (p<0.01).

CONCLUSIONS

During FOB for BAL, HFNC improves gas exchange, avoiding loss of end-expiratory lung volume and preventing increase of diaphragm activation.

TRIAL REGISTRATION NUMBER

NCT04016480.

Role of p38 Mitogen-Activated Protein Kinase in Asthma and COPD: Pathogenic Aspects and Potential Targeted Therapies

Among the various members of the mitogen-activated protein kinase (MAPK) family, p38 MAPK subgroup is the most involved in airway and lung inflammation underlying asthma and chronic obstructive pulmonary disease (COPD). In particular, several environmental agents including aeroallergens, cigarette smoke, airborne pollutants, viral and bacterial pathogens activate the p38α isoform which in turn up-regulates the expression of multiple proinflammatory cytokines and chemokines, as well as the production of some fibrogenic factors. Therefore, p38 MAPK-induced bronchial inflammation and remodelling significantly contribute to the development, persistence and amplification of airflow limitation, which is the hallmark of asthma and COPD. Such advances in our understanding of p38 role in the pathobiology of the above widespread, chronic obstructive respiratory diseases, have led to consider p38 MAPK as a suitable molecular target for novel treatment strategies. Indeed, many studies have been carried out in both animal and clinical settings, with the aim of evaluating the potential therapeutic effects of p38 MAPK inhibitors in both asthma and COPD.

Electrical impedance tomography during spontaneous breathing trials and after extubation in critically ill patients at high risk for extubation failure: a multicenter observational study

Background

This study aims to assess the changes in lung aeration and ventilation during the first spontaneous breathing trial (SBT) and after extubation in a population of patients at risk of extubation failure.

Methods

We included 78 invasively ventilated patients eligible for their first SBT, conducted with low positive end-expiratory pressure (2 cm H₂O) for 30 min. We acquired three 5-min electrical impedance tomography (EIT) records at baseline, soon after the beginning (SBT_0) and at the end (SBT_30) of SBT. In the case of SBT failure, ventilation was reinstituted; otherwise, the patient was extubated and two additional records were acquired soon after extubation (SB_0) and 30 min later (SB_30) during spontaneous breathing. Extubation failure was defined by the onset of post-extubation respiratory failure within 48 h after extubation. We computed the changes from baseline of end-expiratory lung impedance (∆EELI), tidal volume (∆Vt%), and the inhomogeneity index. Arterial blood was sampled for gas analysis. Data were compared between sub-groups stratified for SBT and extubation success/failure.

Results

Compared to SBT success (n = 61), SBT failure (n = 17) showed a greater reduction in ∆EELI at SBT_0 (p < 0.001) and SBT_30 (p = 0.001) and a higher inhomogeneity index at baseline (p = 0.002), SBT_0 (p = 0.003) and SBT_30 (p = 0.005). RR/Vt was not different between groups at baseline but was significantly greater at SBT_0 and SBT_30 in SBT failures, compared to SBT successes (p < 0.001 for both). No differences in ∆Vt% and arterial blood gases were observed between SBT success and failure. The ∆Vt%, ∆EELI, inhomogeneity index and arterial blood gases were not different between patients with extubation success (n = 39) and failure (n = 22) (p > 0.05 for all comparisons).

Conclusions

Compared to SBT success, SBT failure was characterized by more lung de-recruitment and inhomogeneity. Whether EIT may be useful to monitor SBT remains to be determined. No significant changes in lung ventilation, aeration or homogeneity related to extubation outcome occurred up to 30 min after extubation.

Trial registration Retrospectively registered on clinicaltrials.gov (Identifier: NCT03894332; release date 27th March 2019).

Electronic supplementary material

The online version of this article (10.1186/s13613-019-0565-0) contains supplementary material, which is available to authorized users.