Eosinophils depletion therapy for severe asthma management following favorable response to mepolizumab

Biological therapy management from the initial selection of biologics to switching between biologics in severe asthma

The aim of this review is to elaborate the management of biologic therapy from initial selection to switching biologics in severe asthma. A nonsystematic review was performed for biological therapy management in severe asthma. Depending on clinical characteristics and biomarkers, selecting the preferred biologic based on super-responder criteria from previous studies may result in adequate clinical efficacy in most patients. On the other hand, no matter how carefully the choice is made, in some patients, it may be necessary to discontinue the drug due to suboptimal clinical response or even no response. This may result in the need to switch to a different biological therapy. How long the biological treatment of patients whose asthma is controlled with biologics will be continued and according to which criteria they will be terminated remains unclear. It has been shown that in patients with a long history of good response to biologics, asthma control may be impaired when biologics are discontinued, while it may persist in others. Therefore, discontinuation of biologics may be a viable strategy in a particular patient group. Clinicians should make the best use of all predictive factors to identify patients who will most benefit from each biologic. Patients who do not meet a predefined response criterion after sufficient time for response evaluation and who are eligible for one or more alternative biological agents should be offered the opportunity to switch to another biologic. There is no consensus on when the biologics used in severe asthma that produce favorable results should be discontinued. In our opinion, treatment should continue for at least five years, as premature termination may potentially deteriorate asthma control.

A patient case demonstrating the efficacy of benralizumab in uncontrolled severe eosinophilic asthma refractory to omalizumab and mepolizumab treatment

Severe eosinophilic asthma is associated with a heavy burden and impact on daily living in patients experiencing uncontrolled symptoms, exacerbations, and treatment side effects. This case study reports a 49-year-old woman who presented to the severe asthma center with uncontrolled severe asthma despite multiple maintenance medications and omalizumab treatment. On presentation, the patient had experienced two to three hospitalizations per year, frequent asthma exacerbations requiring courses of oral corticosteroids, and symptoms that impacted her quality of life. Omalizumab was previously discontinued, and bronchial thermoplasty was also unsuccessful. The patient stabilized on injectable steroids and commenced mepolizumab once available on prescription. Owing to continued exacerbations and an inability to reduce steroid treatment without exacerbating, mepolizumab was discontinued and the patient commenced benralizumab (30 mg subcutaneously every 4 weeks for the first three doses, every 8 weeks thereafter) under the sole care of the severe asthma center. Benralizumab treatment resulted in a reduction in steroid treatment, zero asthma exacerbations, improved asthma control and lung function, and a marked improvement in activity levels that allowed the patient to participate in a long-distance running event. Additionally, 7 months following the initiation of benralizumab treatment, her blood eosinophils were completely depleted. These findings support the use of benralizumab in patients with refractory uncontrolled severe eosinophilic asthma despite previous biologic treatment with omalizumab and mepolizumab, as improvements in clinical and patient outcomes, including quality of life, can be achieved in difficult-to-treat cases.

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Blood eosinophils reduced to zero in this severe eosinophilic asthma case study.

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Benralizumab allowed a substantial reduction in maintenance corticosteroid use.

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Benralizumab improved exacerbations, asthma control, and quality of life.

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Benralizumab had efficacy after inadequate biologic therapy/bronchial thermoplasty.

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A positive patient-clinician relationship can enhance patient outcomes.

Eosinophils, a Jack of All Trades in Immunity: Therapeutic Approaches for Correcting Their Functional Disorders

BACKGROUND AND OBJECTIVE

Eosinophils are primitive myeloid cells derived from bonemarrow precursors and require the intervention of interleukin (IL)-5 for their survival and persistence in blood and tissues. Under steady-state conditions, they contribute to immune regulation and homeostasis. Under pathological circumstances, eosinophils are involved in host protection against parasites and participate in allergy and inflammation.

DISCUSSION

Mostly, in asthma, eosinophils provoke airway damage via the release of granule contents and IL-13 with mucus hypersecretion and differentiation of goblet cells. Then, tissue remodeling follows with the secretion of transforming growth factor-β. Eosinophils are able to kill helminth larvae acting as antigen-presenting cells with the involvement of T helper (h)-2 cells and subsequent antibody response. However, they also exert pro-worm activity with the production of suppressive cytokine (IL- 10 and IL-4) and inhibition of nitric oxide. Eosinophils may play a pathogenic role in the course of chronic and autoimmune disease, e.g., inflammatory bowel disease and eosinophilic gastroenteritis, regulating Th2 responses and promoting a profibrotic effect. In atopic dermatitis, eosinophils are commonly detected and may be associated with disease severity. In cutaneous spontaneous urticaria, eosinophils participate in the formation of wheals, tissue remodeling and modifications of vascular permeability. With regard to tumor growth, it seems that IgE can exert anti-neoplastic surveillance via mast cell and eosinophil-mediated cytotoxicity, the so-called allergo-oncology. From a therapeutic point of view, monoclonal antibodies directed against IL-5 or the IL-5 receptors have been shown to be very effective in patients with severe asthma. Finally, as an alternative treatment, polyphenols for their anti-inflammatory and anti-allergic activities seem to be effective in reducing serum IgE and eosinophil count in bronchoalveolar lavage in murine asthma.

CONCLUSION

Eosinophils are cells endowed with multiple functions and their modulation with monoclonal antibodies and nutraceuticals may be effective in the treatment of chronic disease.

CD52-targeted depletion by Alemtuzumab ameliorates allergic airway hyperreactivity and lung inflammation

Allergic asthma is a chronic inflammatory disorder associated with airway hyperreactivity (AHR) whose global prevalence is increasing at an alarming rate. Group 2 innate lymphoid cells (ILC2s) and T helper 2 (T_H2) cells are producers of type 2 cytokines, which may contribute to development of AHR. In this study, we explore the potential of CD52-targeted depletion of type 2 immune cells for treating allergic AHR. Here we show that anti-CD52 therapy can prevent and remarkably reverse established IL-33-induced AHR by reducing airway resistance and alleviating lung inflammation. We further show that CD52 depletion prevents and treats allergic AHR induced by clinically relevant allergens such as Alternaria alternata and house dust mite. Importantly, we leverage various humanized mice models of AHR to show new therapeutic applications for Alemtuzumab, an anti-CD52 depleting antibody that is currently FDA approved for treatment of multiple sclerosis. Our results demonstrate that CD52 depletion is a viable therapeutic option for reduction of pulmonary inflammation, abrogation of eosinophilia, improvement of lung function, and thus treatment of allergic AHR. Taken together, our data suggest that anti-CD52 depleting monoclonal antibodies, such as Alemtuzumab, can serve as viable therapeutic drugs for amelioration of T_H2- and ILC2-dependent AHR.

EAACI Biologicals Guidelines-Recommendations for severe asthma

Severe asthma imposes a significant burden on patients, families and healthcare systems. Management is difficult, due to disease heterogeneity, co-morbidities, complexity in care pathways and differences between national or regional healthcare systems. Better understanding of the mechanisms has enabled a stratified approach to the management of severe asthma, supporting the use of targeted treatments with biologicals. However, there are still many issues that require further clarification. These include selection of a certain biological (as they all target overlapping disease phenotypes), the definition of response, strategies to enhance the responder rate, the duration of treatment and its regimen (in the clinic or home-based) and its cost-effectiveness. The EAACI Guidelines on the use of biologicals in severe asthma follow the GRADE approach in formulating recommendations for each biological and each outcome. In addition, a management algorithm for the use of biologicals in the clinic is proposed, together with future approaches and research priorities.

Switching between biologics in severe asthma patients. When the first choice is not proven to be the best

During the last decades, new treatments targeting disease mechanisms referred as biologics have been introduced in the therapy of asthma and currently, five monoclonal antibodies have been approved. Although these therapeutic agents have been formulated to target specific asthma endotypes, it is often difficult for the treating physician to identify which patient is the best candidate for each one of these specific treatments especially in the clinical scenario of a patient in whom clinical characteristics overlap between different endotypes, allowing the selection of more than one biologic agent. As no head-to-head comparisons between these biologics have been attempted, there is no evidence on the superiority of one biologic agent over the other. Furthermore, a physician's first therapeutic decision, no matter how carefully has been made, may often result in suboptimal clinical response and drug discontinuation, indicating the need for switching to a different biologic. In this short review, we discuss the available evidence regarding the switching between biologics in patients with severe asthma and we propose a simple algorithm on switching possibilities in case that the physicians' initial choice is proven not to be the best.

Three cases of severe adolescent asthma treated with mepolizumab: lung function trajectories

Real-world experience with mepolizumab for pediatric asthma is still limited. We report 3 patients who were treated with mepolizumab for severe adolescent asthma. Two patients, a 12-year-old boy and a 14-year-old girl, responded well to mepolizumab and showed apparent improvement in lung function from a downward trend over time before treatment. The third patient, a 16-year-old boy, whose treatment was switched from omalizumab to mepolizumab, did not have satisfactory response. The 2 successful cases had eosinophil counts of 440 and 371/μL and multiple comorbid allergic diseases including food allergies. The clinical benefit to them included elimination of both exacerbation and exercise-induced asthma. Interestingly, the boy's food-induced gastrointestinal symptoms disappeared following start of mepolizumab treatment.