Omalizumab for severe allergic asthma in clinical trials and real-life studies: what we know and what we should address

Benralizumab Efficacy in Late Non-Responders to Mepolizumab and Variables Associated with Occurrence of Switching: A Real-Word Perspective

Overlapping eligibility to different biologics for severe asthma is still challenging, especially when addressing the same target. We aimed to characterize severe eosinophilic asthma patients according to their maintained or reduced response to mepolizumab over time and to explore baseline variables significantly associated with the occurrence of switching to benralizumab. We performed a multicentre retrospective observational study evaluating OCS reduction, exacerbation rate, lung function, exhaled nitric oxide levels (FeNO), Asthma control test (ACT), and blood eosinophil concentrations at baseline and before and after switching occurrence among 43 female and 25 male patients with severe asthma aged 23 to 84 years. Younger age, higher OCS daily dose and lower blood eosinophils at baseline were associated with a significantly higher risk (odds) for switching occurrence. All the patients showed an optimal response to mepolizumab, up to six months. The need for switching, according to the above-mentioned criterion, occurred for 30 out of 68 patients after a median time of 21 months (Q1-Q3: 12-24) from mepolizumab initiation. At the follow-up time-point after the switch (median time: 31 months, Q-Q3: 22-35), all the outcomes substantially improved and no cases of poor clinical response to benralizumab were detected. Although the small sample size and the retrospective design represent major limitations, to our knowledge, our study provides the first real-word focus on clinical variables potentially predicting a better response to anti IL-5r in patients fully eligible for both mepolizumab and benralizumab and suggests that in late non responder patients to mepolizumab, more robustly targeting the IL-5 axis may be effective.

Biologicals for severe asthma: what we can learn from real-life experiences?

PURPOSE OF REVIEW

Severe asthma is a serious disease affecting about 5-10% of asthmatic patients. Often patients with this kind of asthma requires periodical courses or daily intake of oral corticosteroids, to control symptoms. In the last few years several biological drugs have been developed with the aim to decrease exacerbations and reduce or suspend intake of systemic steroids in severe asthmatic patients. Clinical trials demonstrated the efficacy and the safety of biological antibodies in asthma, but it is already known that randomized controlled trials alone are not sufficient to provide complete information on a drug.

RECENT FINDINGS

After marketing of monoclonal antibodies has been developed several real-life studies with the aim to observe how drugs, tested only on trial patients, are able to provide adequate effectiveness even on 'real' patients; indeed, it is well known that the latter differ in some characteristics from the patients of the trials.

SUMMARY

The results of this analysis confirm the good efficacy of the biologics similarly in real-life patients, also ensuring a promising safety even in periods of observation longer than those of the randomized controlled trials.

Biologics for the Treatments of Allergic Conditions: Severe Asthma

By selectively targeting specific steps of the immune inflammation cascade, biologic drugs for severe asthma have substantially contributed to increase the standard of care, to reduce drug-related morbidity. and most importantly to ameliorate patients' quality of life. Upcoming molecules are going to provide a chance for severe phenotypes besides Th2 high through the interaction with epithelial and innate immunity. Some practical aspects including optimal treatment duration, the possibility of a dose treatment modulation, the place and relevance of ICS in best responders are still under debate. Long-term safety, especially when interacting with innate immunity needs to be further investigated.

Long-term omalizumab efficacy in allergic rhinitis

BACKGROUND

Omalizumab therapy was found to be safe and effective as an add-on therapy for patients with poorly controlled severe asthma. Although several studies over the last decade have demonstrated its efficacy in other Immunoglobulin E related diseases, its use in such conditions is off-label.

OBJECTIVE

This study aimed to assess the effectiveness of long-term therapy with Omalizumab in patients with persistent severe allergic rhinitis and inadequately controlled severe asthma.

METHODS

Patients with poorly controlled severe asthma and persistent allergic rhinitis were enrolled and treated with Omalizumab for 36 months with every four-week subcutaneous administration. The efficacy assessment included the severity of AR symptoms every six months using Visual Analogue Scale, Asthma Control Test, nasal endoscopy, spirometry, and biomarkers (blood eosinophils and neutrophils, fractional exhaled nitric oxide, total IgE).

RESULTS

Eleven patients aged between 26 and 70 years were enrolled, and 10 completed the study. A significant improvement of allergic rhinitis symptoms, Asthma Control Test, and lung function was observed. There was also a reduction in the status of the biomarkers at the end of the study.

CONCLUSION

Long-term therapy with Omalizumab was effective and safe in treating severe persistent allergic rhinitis and concomitant asthma.

Evolving phenotypes to endotypes: is precision medicine achievable in asthma?

Introduction: The development of biologic molecules led to a drastic change in the therapeutic approach to asthma. With the prospect of acting on different pathophysiological mechanisms of the disease, the idea of precision medicine was developed, in which a single molecule is able to modify a specific triggering mechanism. Thus, it seemed limiting to stop at the distinction of patients phenotypes and the concept of endotypes became more relevant in the therapeutic approach.Areas covered: This review deepened the topic of precision medicine through the transition from phenotyping to endotyping. We performed a review of the literature, preferring articles quoted in Medline and published in journals with an impact factor. Results showed that it is fundamental to take into consideration the role of biomarkers and the related therapies currently available for precision medicine.Expert opinion: The possible overlap of patients in different phenotypes requires a more precise classification, which considers endotypization. With the development of biological drugs able to modify and modulate some pathophysiological mechanisms of the disease, the theoretical concept of endotyping becomes practical, allowing the clinician to choose the specific mechanism to 'attack' in order to control the disease.

What have recent advances in therapy taught us about severe asthma disease mechanisms?

Introduction: Severe asthma still represents a worldwide challenge. The need for further treatment options has stimulated basic and pharmacological research to focus on the immune and inflammatory background of asthma. The new biologic drugs express the considerable advances in the field and besides providing a revolutionary treatment option for severe asthma, contribute themselves to better understand the pathophysiologic mechanisms they address, paving the way to new potential targets.Areas covered: A selective search on PubMed and Medline was performed, including the evidence on immunology of severe asthma published up to May 2019 by focusing on the immunological effects of biologic drugs underlying their clinical outcomes.Expert opinion: The recent pharmacological research in the field of biologics has represented an exceptional opportunity for exploring severe asthma mechanisms. However, some points deserve to be addressed by further investigation. Although in the absence of safety warnings so far, interfering with the immune system may raise some safety concerns, especially in the long-term use. Particularly when interacting with epithelial and innate immunity the selection of candidates probably deserves special caution. Also, whether biologics exert a true disease-modifying effect is not completely clear. As a direct practical implication, the optimal treatment duration is still controversial.

Mepolizumab for severe eosinophilic asthma: a real-world snapshot on clinical markers and timing of response

Background: Few studies have provided real-world evidence of mepolizumab efficacy and safety. We aimed to evaluate mepolizumab for severe eosinophilic asthma in daily clinical practice.Research design and methods: Patients included in the RINOVA (Interdisciplinary Network for the management of severe asthma in Veneto region, Italy) database were investigated. Blood eosinophil count, forced expiratory volume in 1 second, % of predicted (FEV1%), fractional exhaled nitric oxide (FeNO), asthma control test (ACT), oral steroid (OCS) intake, and exacerbation rate were evaluated during mepolizumab treatment.Results: 69 patients were enrolled (mean age: 55.1 years; 60.9% females). A significant improvement was detected at one month with respect to blood eosinophils (median level at baseline: 710/μl; -620/μl, p < 0,001), FEV1% (median value at baseline 87; range: 79-101; +4, p = 0.001) and ACT (median value at baseline 18; range: 14-20.5;+4, <0.001). A significant reduction of FeNO was observed six months after the treatment start, when the exacerbation rate and the mean OCS dose significantly decreased (respectively: Δ reduction -3; p < 0.001 and -5 mg; p < 0.001).Conclusions: Our study provides real-world evidence of mepolizumab safety and confirms its dramatic steroid sparing effect. The greatest clinical change (ACT and FEV1) was observed within the first month.

Effectiveness and safety of mepolizumab in severe refractory eosinophilic asthma: results in clinical practice

Background

Asthma is an inflammatory disease of the airways with symptoms that vary over time and intensity, sometimes leading to disability or even death. Eosinophilic asthma accounts for 25% of cases of severe asthma. It is mediated by eosinophils regulated by interleukin-5 (IL-5), the target of mepolizumab, which has been recently licensed as an add-on treatment of severe refractory eosinophilic asthma. The aim of this study was to evaluate the effectiveness and safety of mepolizumab in clinical practice.

Methods

A multicentre, retrospective, and descriptive study covering a year was conducted in a province of Spain with more than 500,000 inhabitants. Every patient prescribed with mepolizumab since its introduction into the hospital was included in the study. Clinical parameters were collected from the pharmacists' counselling reports from electronic prescription software and electronic patient records. Effectiveness was assessed as a decrease in the exacerbation frequency and/or a reduction in the use of oral corticosteroids (OCS) compared to the previous year.

Results

A total of 25 patients were studied, but only 23 could be evaluated by the cut-off date. A decrease in the exacerbation frequency was observed in 19 (82.6%) patients, 11 of them without any exacerbation during the treatment. A relative reduction of 87% in the exacerbation rate per year was obtained. A total of 15 patients were on regular OCS - 9 patients (60%) reduced their average dose, whilst 4 (26.7%) patients completely abandoned OCS. Safety was evaluated based on reported adverse effects. Adverse events were observed in 12 patients, the most common being headache, arthralgia, and dizziness/nausea.

Conclusion

Mepolizumab has been shown to be effective based on the high decrease in the exacerbation frequency and reduced use of OCS. Reported adverse effects were mostly mild and appeared in half of the patients; some of the adverse events had not been previously described in pivotal trials.

New horizons for the treatment of severe, eosinophilic asthma: benralizumab, a novel precision biologic

In the last decades, the increasing evidence concerning inflammation mechanisms underlying severe eosinophilic asthma has highlighted new potential therapeutic targets and has paved the way to new selective biologic drugs. Understanding the mechanism of action and the clinical outcomes of a particular drug along with the clinical and biological characteristics of the patient population for which that drug was intended may ensure appropriate selection of patients that will respond to that drug. Under this perspective, the present review will focus on the mechanisms of action and clinical evidence of benralizumab as a treatment option for severe eosinophilic asthma, in order to provide a concise overview and a reference for clinical practice. Benralizumab is a fully humanized afucosylated IgG1κ mAb that binds to an epitope on IL-5 Rα, and inhibits IL-5 signaling. Benralizumab also sustains antibody-directed cell-mediated cytotoxicity (ADCC) of eosinophils and basophils and consequently depletes IL-5Rα-expressing cells. As a result, it is responsible for a substantial depletion of blood, tissue, and bone marrow eosinophilia. This unique mechanism of action may account for a more complete and rapid action profile. Randomized clinical trials have demonstrated that benralizumab provides an optimal safety profile, and is able to significantly reduce asthma exacerbations, oral steroid intake, and to improve lung function. Some clinical predictors of enhanced clinical response to benralizumab have also been identified, including: a level of blood eosinophils ≥300 μL⁻¹, oral steroids use, the presence of nasal polyposis, FVC <65% of predicted, and a history of three or more exacerbations per year at baseline. These results can be helpful in identifying the best responder patients to benralizumab. As a step forward, the definition of the responder profile for each of the available biological treatment options will potentially support even more the pathway to precision medicine and the critical matching of the right drug with the right patient.

The North-Western Italian experience with anti IL-5 therapy amd comparison with regulatory trials

BACKGROUND

The severe forms of asthma represent a major burden, because of severity of symptoms, costs and impact on everyday life. Recently, Mepolizumab (MEP) was approved and marketed for the treatment of hypereosinophilic severe asthma. This anti-IL-5 monoclonal antibody reduced exacerbation rates and oral corticosteroid (OCS) use in well selected patients. The aim of this study was to evaluate the characteristics of patients receiving MEP in a real-life setting. Thus, we describe a retrospective analysis of patients treated with MEP in six centres in North Western Italy, including those who participated in the main regulatory trials.

METHODS

The baseline data, before prescription, from six North Western Italy severe asthma clinics, between June 1st 2017 and December 31st 2017, were evaluated. The collected real-life data were then compared with those of SIRUS, MENSA, DREAM and MUSCA trials.

RESULTS

Sixty-five patients were included (45% female; mean age 56 years; age range 19-84). Main observed differences with regulatory trials could be observed in eosinophils blood count at baseline, where the mean of our real-life patients (653 cells/μL) was overall higher than the one of all trials (240 cells/μL, 296 cells/μL, 253 cells/μL; p <  0.0001). The incidence of polyposis was also significantly higher in our sample (72% vs. 24%, 49%, 10%, 19%; p <  0.0001). The daily average dose of OCS was lower in our real-life patients (9 mg), if compared with SIRIUS (13.7 mg), MENSA (13.2) and MUSCA (13), and similar to the data published in DREAM (10.8).

CONCLUSIONS

The comparison of real-life patients' characteristics with regulatory trials, displayed several apparent discrepancies. The demographic and clinical aspects were similar in all groups, whereas other features (eosinophil count, pulmonary function FEV1%) differed. These data, for the first time, could represent a basis for a more accurate prescription of the drug.

Long-Term Omalizumab Treatment: A Multicenter, Real-Life, 5-Year Trial

BACKGROUND

Omalizumab has demonstrated therapeutic benefits both in controlled clinical trials and real-life studies. However, research concerning the long-term effects and tolerability of omalizumab is needed. The main objective of this study was to evaluate the effectiveness and tolerability of treatment with omalizumab for up to 5 years.

METHODS

A multicenter, retrospective, chart-based study was carried out to compare documented exacerbations, hospitalizations, systemic steroid requirement, FEV1, and asthma control test (ACT) results during 1 year prior to omalizumab treatment versus at 1, 3, and 5 years of treatment. Adverse events and reasons for discontinuation were also recorded at each time point.

RESULTS

Four hundred and sixty-five patients were enrolled in the study. Outcome variables had improved after the 1st year and were sustained after the 3rd and 5th years of treatment with omalizumab. Omalizumab treatment reduced the asthma exacerbation rate by 71.3% (p < 0.001) at 1 year, 64.3% (p < 0.001) at 3 years, and 54.8% (p = 0.002) at 5 years. The hospitalization rate also decreased; by the 5th year of the treatment no patients were hospitalized. ACT results had also improved significantly: 12 (p < 0.001) at 1 year, 12 (p < 0.001) at 3 years, and 12 (p = 0.002) at 5 years. Overall, 12.7% of patients reported adverse events (most of these were mild-to-moderate) and the overall dropout rate was 9.0%.

CONCLUSION

Omalizumab had a significant effect on asthma outcomes and this effect was maintained over 5 years. The drug was found to be generally safe and treatment compliance was good.

Nordic consensus statement on the systematic assessment and management of possible severe asthma in adults

Although a minority of asthma patients suffer from severe asthma, they represent a major clinical challenge in terms of poor symptom control despite high-dose treatment, risk of exacerbations, and side effects. Novel biological treatments may benefit patients with severe asthma, but are expensive, and are only effective in appropriately targeted patients. In some patients, symptoms are driven by other factors than asthma, and all patients with suspected severe asthma ('difficult asthma') should undergo systematic assessment, in order to differentiate between true severe asthma, and 'difficult-to-treat' patients, in whom poor control is related to factors such as poor adherence or co-morbidities. The Nordic Consensus Statement on severe asthma was developed by the Nordic Severe Asthma Network, consisting of members from Norway, Sweden, Finland, Denmark, Iceland and Estonia, including representatives from the respective national respiratory scientific societies with the aim to provide an overview and recommendations regarding the diagnosis, systematic assessment and management of severe asthma. Furthermore, the Consensus Statement proposes recommendations for the organization of severe asthma management in primary, secondary, and tertiary care.

Biologic agents for severe asthma patients: clinical perspectives and implications

Asthma is a chronic inflammatory multifactorial disorder of the airways characterized by the involvement of immune cells and mediators in its onset and maintenance. Traditional therapeutic strategies have been unsatisfactory in controlling the underlying pathology, especially in the more severe states. Hence in the last couple of decades, new biological approaches targeting molecular mediators have been developed. In this narrative review we examine biological agents currently available for the management of severe asthma, focusing our attention on their clinical application, pros and cons, and in particular on gaps regarding the use of these agents. The most well-known and used biologic agent in clinical practice is omalizumab, though there is emerging evidence for mepolizumab too. The future of these biological therapies is to broaden our knowledge of their practical use and ascertain predictive biomarkers, or define an algorithm, useful in the optimal application of these 'biological weapons'.

Effectiveness and response predictors of omalizumab in a severe allergic asthma population with a high prevalence of comorbidities: the Australian Xolair Registry

BACKGROUND

Severe asthma is a high impact disease. Omalizumab targets the allergic inflammatory pathway; however, effectiveness data in a population with significant comorbidities are limited.

AIMS

To describe severe allergic asthma, omalizumab treatment outcomes and predictors of response among the Australian Xolair Registry participants.

METHODS

A web-based post-marketing surveillance registry was established to characterise the use, effectiveness and adverse effects of omalizumab (Xolair) for severe allergic asthma.

RESULTS

Participants (n = 192) (mean age 51 years, 118 female) with severe allergic asthma from 21 clinics in Australia were assessed, and 180 received omalizumab therapy. They had poor asthma control (Asthma Control Questionnaire, ACQ-5, mean score 3.56) and significant quality of life impairment (Asthma-related Quality of Life Questionnaire score 3.57), and 52% were using daily oral corticosteroid (OCS). Overall, 95% had one or more comorbidities (rhinitis 48%, obesity 45%, cardiovascular disease 23%). The omalizumab responder rate, assessed by an improvement of at least 0.5 in ACQ-5, was high at 83%. OCS use was significantly reduced. The response in participants with comorbid obesity and cardiovascular disease was similar to those without these conditions. Baseline ACQ-5 ≥ 2.0 (P = 0.002) and older age (P = 0.05) predicted the magnitude of change in ACQ-5 in response to omalizumab. Drug-related adverse events included anaphylactoid reactions (n = 4), headache (n = 2) and chest pains (n = 1).

CONCLUSION

Australian patients with severe allergic asthma report a high disease burden and have extensive comorbidity. Symptomatic response to omalizumab was high despite significant comorbid disease. Omalizumab is an effective targeted therapy for severe allergic asthma with comorbidity in a real-life setting.

dNP2-ctCTLA-4 inhibits German cockroach extract-induced allergic airway inflammation and hyper-responsiveness via inhibition of Th2 responses

German cockroaches are major household allergens that can trigger allergic airway inflammatory diseases with sensitive T-cell responses. Although the use of immune modulatory biologics, such as antibodies, to mediate allergic responses has recently been examined, only systemic administration is available because of the size limitations on intranasal administration. Here we utilized a cell-permeable peptide, dNP2, to deliver the cytoplasmic domain of cytotoxic T-lymphocyte antigen-4 (ctCTLA-4) through the airway epithelium to modulate Th2 responses in a German cockroach extract (GCE)-induced allergic airway inflammation model. The intranasal delivery efficiency of the dNP2-dTomato protein to the lungs was higher in GCE-induced asthmatic lung parenchymal cells compared to the sham cells. Intranasal administration of the dNP2-ctCTLA-4 protein inhibited airway hyper-responsiveness and reduced airway inflammation and remodeling, including goblet cell metaplasia and collagen deposition around the bronchi. The number of infiltrated cells, including eosinophils, and the levels of IL-4, IL-5, IL-13 and IFN-γ in the lungs were significantly reduced, presumably owing to inhibition of Th2 differentiation. However, intranasal administration of CTLA4-Ig did not inhibit airway inflammation. These results collectively suggest that dNP2-ctCTLA-4 is an efficient intranasally applicable candidate biologic for treating allergic asthma.

SANI-Severe Asthma Network in Italy: a way forward to monitor severe asthma

Even if severe asthma (SA) accounts for 5-10% of all cases of the disease, it is currently a crucial unmet need, owing its difficult clinical management and its high social costs. For this reason several networks, focused on SA have been organized in some countries, in order to select these patients, to recognize their clinical features, to evaluate their adherence, to classify their biological/clinical phenotypes, to identify their eligibility to the new biologic therapies and to quantify the costs of the disease. Aim of the present paper is to describe the ongoing Italian Severe Asthma Network (SANI). Up today 49 centres have been selected, widespread on the national territory. Sharing the same diagnostic protocol, data regarding patients with SA will be collected and processed in a web platform. After their recruitment, SA patients will be followed in the long term in order to investigate the natural history of the disease. Besides clinical data, the cost/benefit evaluation of the new biologics will be verified as well as the search of peculiar biomarker(s) of the disease.

Can the response to Omalizumab be influenced by treatment duration? A real-life study

OBJECTIVE

It is unknown whether Omalizumab effectiveness changes over the course of time. Our retrospective real-life study tried to analyze whether Omalizumab response may be influenced by treatment duration.

METHODS

340 severe asthmatics treated with Omalizumab for different periods of time were recruited. They were subdivided into 4 groups according to the Omalizumab treatment length: <12, between 12 and 24, between 24 and 60 and >60 months. Omalizumab treatment results (FEV₁, exacerbations, ACT, SABA use, asthma control levels, medications used e and ICS doses) were compared.

RESULTS

ACT, exacerbations, GINA control levels, ICS doses and SABA use were similar in all groups with different Omalizumab treatment durations. Using a linear regression model, corrected for all confounding variables, a higher significant positive increase in FEV₁% in subjects treated for 12-24 (β = 9.49; p = 0.034) or 24-60 months (β = 8.56; p = 0.043) was found when compared with subjects treated for a shorter period. Treatment duration was positively associated with a step down of the other associated therapies (OR: 1.013; p = 0.019). This association was more relevant (OR: 4.167; p = 0.005) when we considered Omalizumab treatment duration >60 months compared to the shorter therapy. In particular, the percentage of subjects that were taking Montelukast, LABAs and oral corticosteroids was lower in the group treated with Omalizumab for a longer period of time.

CONCLUSION

In real-life, the positive Omalizumab response remained stable for over 60 months. Long term Omalizumab treatment may lead to a discontinuation of some associated medications and to a slowing down of FEV₁ decline.

Evaluation of long-term safety and efficacy of omalizumab in elderly patients with uncontrolled allergic asthma

BACKGROUND

Severe asthma management in elderly patients may be difficult because of increased comorbid conditions, polypharmacy, physiologic changes that occur with aging, incorrect use of inhaler devices, and poor adherence.

OBJECTIVE

To evaluate the long-term safety and efficacy of the anti-IgE antibody omalizumab in elderly (aged ≥65 years) patients with uncontrolled allergic asthma.

METHODS

The efficiency and adverse effects of omalizumab treatment were evaluated based on data extracted from medical records. Patients were evaluated monthly for efficacy and adverse reactions. Treatment efficacy was evaluated by level of asthma symptom control, using the Global Initiative for Asthma guideline.

RESULTS

Nineteen consecutive elderly patients with asthma (female to male ratio, 14:5) formed our cohort. The mean (SD) age, disease duration, and total IgE level were 69.3 (5.8) years, 19.4 (8.6) years, and 299.1 (197.2) IU/mL, respectively. The mean (SD) duration of omalizumab treatment was 35.6 (17.8) months (range, 9-66 months). All the patients had at least 1 perennial inhalant allergen sensitivity and had uncontrolled allergic asthma. Elderly patients experienced no significantly important adverse reaction considered to be related to omalizumab treatment. Only 1 patient had a local adverse reaction and 1 had myalgia that was considered to be drug related. After omalizumab treatment, asthma symptoms were well controlled in 9 patients (47.4%) and partly controlled in 8 patients (42.1%). Two of the patients (10.5%) still had uncontrolled asthma.

CONCLUSION

Our study found that omalizumab is a well-tolerated and effective therapy for elderly patients with uncontrolled asthma.

Effects of omalizumab in severe asthmatics across ages: A real life Italian experience

BACKGROUND

This retrospective study aimed at evaluating long-term effects of Omalizumab in elderly asthmatics in a real-life setting.

METHODS

105 consecutive severe asthmatics (GINA step 4-5; mean FEV₁% predicted:66 ± 15.7) treated with Omalizumab for at least 1 year (treatment mean duration 35.1 ± 21.7 months) were divided into 3 groups according to their age at Omalizumab treatment onset: 18-39, 40-64 and ≥ 65 years.

RESULTS

Comorbidities, number of overweight/obese subjects and patients with late-onset asthma were more frequent among older people. A similar reduction of inhaled corticosteroids dosage and SABA on-demand therapy was observed in all groups during Omalizumab treatment; a similar FEV₁ increased was also observed. Asthma Control Test (ACT) improved significantly (p < 0.001) in the three groups, increasing from 15 [IQR:12-18] to 24 [IQR:22-25] in younger subjects, from 14 [IQR:10-16] to 21 [IQR:20-23] in the 40-64-year-group and from 15 [IQR:12-16] to 20 [IQR:18-22] in elderly patients where improvement was lower (p = 0.039) compared to younger people. Asthma exacerbations decreased significantly after Omalizumab but the percentage of exacerbation-free patients was higher in younger people (76.9%) compared to middle aged patients (49.2%) and the elderly (29%) (p = 0.049). After Omalizumab treatment, the risk for exacerbations was lower in subjects aged 40-64 (OR = 0.284 [CI95% = 0.098-0.826], p = 0.021) and 18-39 (OR = 0.133 [CI95% = 0.026-0.678], p = 0.015), compared to elderly asthmatics. Also, a significantly reduced ACT improvement (β = -1.070; p = 0.046) passing from each age class was observed.

CONCLUSION

Omalizumab improves all asthma outcomes independently of age, although the magnitude of the effects observed in the elderly seems to be lower than in the other age groups.

Drop-out rate among patients treated with omalizumab for severe asthma: Literature review and real-life experience

Background

In patients with asthma, particularly severe asthma, poor adherence to inhaled drugs negatively affects the achievement of disease control. A better adherence rate is expected in the case of injected drugs, such as omalizumab, as they are administered only in a hospital setting. However, adherence to omalizumab has never been systematically investigated. The aim of this study was to review the omalizumab drop-out rate in randomized controlled trials (RCTs) and real-life studies. A comparative analysis was performed between published data and the Italian North East Omalizumab Network (NEONet) database.

Results

In RCTs the drop-out rate ranged from 7.1 to 19.4 %. Although the reasons for withdrawal were only occasionally reported, patient decision and adverse events were the most frequently reported causes. In real-life studies the drop-out rate ranged from 0 to 45.5 %. In most cases lack of efficacy was responsible for treatment discontinuation. According to NEONet data, 32 % of treated patients dropped out, with an increasing number of drop outs observed over time. Patient decision and lack of efficacy accounted for most treatment withdrawals.

Conclusions

Treatment adherence is particularly crucial in patients with severe asthma considering the clinical impact of the disease and the cost of non-adherence. The risk of treatment discontinuation has to be carefully considered both in the experimental and real-life settings. Increased knowledge regarding the main reasons for patient withdrawal is important to improve adherence in clinical practice.

CD11b+ and Sca-1+ Cells Exert the Main Beneficial Effects of Systemically Administered Bone Marrow-Derived Mononuclear Cells in a Murine Model of Mixed Th2/Th17 Allergic Airway Inflammation

A murine model of severe clinical asthma was used to study which bone marrow-derived mononuclear cells (BMDMCs) are responsible for ameliorating airway hyperresponsiveness and lung inflammation. BMDMCs depleted of either CD11b-positive cells (monocytes, macrophages, dendritic cells) or Sca-1-positive cells (bone marrow-derived mesenchymal stromal cells) were unable to ameliorate these conditions in this model. Depletion of the other cell types did not diminish the ameliorating effects of BMDMC administration.

Systemic administration of bone marrow-derived mononuclear cells (BMDMCs) or bone marrow-derived mesenchymal stromal cells (MSCs) reduces inflammation and airway hyperresponsiveness (AHR) in a murine model of Th2-mediated eosinophilic allergic airway inflammation. However, since BMDMCs are a heterogeneous population that includes MSCs, it is unclear whether the MSCs alone are responsible for the BMDMC effects. To determine which BMDMC population(s) is responsible for ameliorating AHR and lung inflammation in a model of mixed Th2-eosinophilic and Th17-neutrophilic allergic airway inflammation, reminiscent of severe clinical asthma, BMDMCs obtained from normal C57Bl/6 mice were serially depleted of CD45, CD34, CD11b, CD3, CD19, CD31, or Sca-1 positive cells. The different resulting cell populations were then assessed for ability to reduce lung inflammation and AHR in mixed Th2/Th17 allergic airway inflammation induced by mucosal sensitization to and challenge with Aspergillus hyphal extract (AHE) in syngeneic C56Bl/6 mice. BMDMCs depleted of either CD11b-positive (CD11b+) or Sca-1-positive (Sca-1+) cells were unable to ameliorate AHR or lung inflammation in this model. Depletion of the other cell types did not diminish the ameliorating effects of BMDMC administration. In conclusion, in the current model of allergic inflammation, CD11b+ cells (monocytes, macrophages, dendritic cells) and Sca-1+ cells (MSCs) are responsible for the beneficial effects of BMDMCs.

Significance

This study shows that bone marrow-derived mononuclear cells (BMDMCs) are as effective as bone marrow-derived mesenchymal stromal cells (MSCs) in ameliorating experimental asthma. It also demonstrates that not only MSCs present in the pool of BMDMCs are responsible for BMDMCs’ beneficial effects but also monocytes, which are the most important cell population to trigger these effects. All of this is in the setting of a clinically relevant model of severe allergic airways inflammation and thus provides further support for potential clinical use of cell therapy using MSCs, BMDMCs, and also adult cells such as monocytes in patients with severe asthma.

Current and emerging treatments for severe asthma

Severe asthma, which is poorly controlled despite the elimination of modifiable factors and the correct use of standard therapy, accounts only for 5% of people with asthma but it contributes to approximately 50% of the economic costs of asthma. Because of this unmet need, novel therapies have been developed for optimal treatment of these patients. The use of tiotropium, omalizumab, mepolizumab and thermoplasty in well-selected patients provides better control and most importantly a reduction in asthma exacerbations.