Reslizumab in the management of poorly controlled asthma: the data so far

Subsets of Eosinophils in Asthma, a Challenge for Precise Treatment

The existence of eosinophils was documented histopathologically in the first half of the 19th century. However, the term “eosinophils” was first used by Paul Ehrlich in 1878. Since their discovery and description, their existence has been associated with asthma, allergies, and antihelminthic immunity. Eosinophils may also be responsible for various possible tissue pathologies in many eosinophil-associated diseases. Since the beginning of the 21st century, the understanding of the nature of this cell population has undergone a fundamental reassessment, and in 2010, J. J. Lee proposed the concept of “LIAR” (Local Immunity And/or Remodeling/Repair), underlining the extensive immunoregulatory functions of eosinophils in the context of health and disease. It soon became apparent that mature eosinophils (in line with previous morphological studies) are not structurally, functionally, or immunologically homogeneous cell populations. On the contrary, these cells form subtypes characterized by their further development, immunophenotype, sensitivity to growth factors, localization, role and fate in tissues, and contribution to the pathogenesis of various diseases, including asthma. The eosinophil subsets were recently characterized as resident (rEos) and inflammatory (iEos) eosinophils. During the last 20 years, the biological therapy of eosinophil diseases, including asthma, has been significantly revolutionized. Treatment management has been improved through the enhancement of treatment effectiveness and a decrease in the adverse events associated with the formerly ultimately used systemic corticosteroids. However, as we observed from real-life data, the global treatment efficacy is still far from optimal. A fundamental condition, “sine qua non”, for correct treatment management is a thorough evaluation of the inflammatory phenotype of the disease. We believe that a better understanding of eosinophils would lead to more precise diagnostics and classification of asthma subtypes, which could further improve treatment outcomes. The currently validated asthma biomarkers (eosinophil count, production of NO in exhaled breath, and IgE synthesis) are insufficient to unveil super-responders among all severe asthma patients and thus give only a blurred picture of the adepts for treatment. We propose an emerging approach consisting of a more precise characterization of pathogenic eosinophils in terms of the definition of their functional status or subset affiliation by flow cytometry. We believe that the effort to find new eosinophil-associated biomarkers and their rational use in treatment algorithms may ameliorate the response rate to biological therapy in patients with severe asthma.

A comparison of biologicals in the treatment of adults with severe asthma - real-life experiences

BACKGROUND

Anti-IgE (omalizumab) and anti-IL5/IL5R (reslizumab, mepolizumab and benralizumab) treatments are available for severe allergic and eosinophilic asthma. In these patients, studies have shown beneficial effects in oral corticosteroid use and exacerbations. The aim of this retrospective single-center study was to evaluate the effect of biological therapy on severe asthma and to compare different therapies.

METHODS

We collected and analysed results of anti-IL5/IL5R and anti-IgE therapies for asthma from January 2009 until October 2019 in specialized care. We compared number of exacerbations, asthma symptoms and use of per oral corticosteroids and antimicrobics because of asthma before and during biological therapy, and in a separate analysis need for per oral corticosteroids, antimicrobics or surgery due to upper respiratory tract diseases in asthmatics receiving biologicals. The analyses were done using the Chi square test, T-test or Mann-Whitney U -test, the Kruskall-Wallis test or the Wilcoxon test.

RESULTS

Of 64 patients, 40 used continuous per oral corticosteroid therapy prior to biological therapy. The mean daily dose of per oral corticosteroid was reduced in those with anti-IL5/IL5R therapy (- 3.0 mg, p = 0.02). The number of annual per oral corticosteroid courses decreased in both the anti-IL5/IL5R (- 2.8 courses, p < 0.05) and anti-IgE groups (- 1.3 courses, p < 0.05). The number of annual antibiotic courses (- 0.7 courses, p = 0.04) and total number of exacerbation events (- 4.4 events/year, p < 0.05) were reduced in the anti-IL5/IL5R group. In the 55 asthma patients analysed for upper respiratory tract findings, the results suggested a reduction in need for chronic rhinosinusitis surgery during biological therapy.

CONCLUSIONS

Results with biological therapies in this real-life clinical setting are comparable to those reported in clinical trials. Biological therapy reduces exacerbations and per oral corticosteroid use.

TRIAL REGISTRATION

NCT04158050, retrospectively registered 6.11.2019.

Predicting Responders to Reslizumab after 16 Weeks of Treatment Using an Algorithm Derived from Clinical Studies of Patients with Severe Eosinophilic Asthma

RATIONALE

Reslizumab is a humanized anti-IL-5 monoclonal antibody used as add-on maintenance treatment for patients with uncontrolled eosinophilic asthma.

OBJECTIVES

To predict response and nonresponse to intravenous reslizumab at 52 weeks with an algorithm we developed based on clinical indicators from pivotal clinical trials.

METHODS

Patients aged 18 years and older who met Global Initiative for Asthma 4 or 5 criteria and received intravenous reslizumab (n = 321) in two trials ( www.clinicaltrials.gov identifiers, NCT01287039 and NCT01285323) were selected as the data source. A mathematical model was constructed that was based on change from baseline to 16 weeks in Asthma Control Questionnaire and Asthma Quality of Life Questionnaire scores and FEV₁, and number of clinical asthma exacerbations during the year before enrollment and in the first 16 weeks of treatment, and these measures were evaluated for their ability to predict the outcome at 52 weeks: responder, nonresponder, or indeterminate.

MEASUREMENTS AND MAIN RESULTS

The algorithm predicted that 276 patients would be classified as responders; in 248 (89.9%), the prediction was correct. In comparison, 26 patients were predicted to be nonresponders; 50.0% of these predictions were correct. Nineteen patients were classified as indeterminate. The algorithm had 95.4-95.5% sensitivity and 40.6-54.1% specificity. Jackknife and cross-study validation confirmed the robustness of the algorithm.

CONCLUSIONS

Our algorithm enabled prediction at 16 weeks of treatment of the response to intravenous reslizumab treatment at 52 weeks, but it was not suitable for predicting nonresponse. A positive score at 16 weeks should encourage continued treatment, and a negative score should prompt close monitoring to determine whether discontinuation is warranted.

Comparison of Monoclonal Antibodies for Treatment of Uncontrolled Eosinophilic Asthma

OBJECTIVE

To summarize the current literature for Food and Drug Administration (FDA)-approved monoclonal antibodies used as add-on maintenance therapy in uncontrolled eosinophilic asthma.

DATA SOURCES

PubMed was searched on December 17, 2018 using keywords: asthma, eosinophilic asthma, omalizumab, reslizumab, mepolizumab, benralizumab, and dupilumab.

STUDY SELECTION

Studies evaluating safety and efficacy of monoclonal antibodies for treatment of severe or eosinophilic asthma were included.

RESULTS

Twenty-one randomized, double-blind, placebo-controlled trials evaluating the current FDA-approved monoclonal antibodies (omalizumab, mepolizumab, reslizumab, benralizumab, and dupilumab) for the treatment of uncontrolled eosinophilic asthma were included. The studies demonstrated clinically significant reductions in asthma exacerbations, symptoms, emergency room visits, eosinophil counts, and improvements in pulmonary function and asthma-related quality of life.

CONCLUSION

Five monoclonal antibodies are available for uncontrolled eosinophilic asthma. Choice depends on patient factors. Future studies should focus on cost-effectiveness of treatment, drug-drug comparisons, and long-term efficacy and safety.

[Patients in the IDEAL cohort: A snapshot of severe asthma in France]

INTRODUCTION

This paper reports the French data from a post-hoc analysis of the international IDEAL study, which aimed to describe a recent cohort of patients with severe asthma, the impact of the disease on quality of life, as well as the population of patients eligible for treatment with omalizumab, mepolizumab and reslizumab.

METHODS

Eligible patients were≥12 years of age, with severe asthma (GINA steps 4 and 5).

RESULTS

A total of 129 patients were included in this post-hoc analysis. Their mean age was 53 years, the majority were overweight, they were mainly women (64%) and had at least one medical comorbidity (85%). More than half had suffered from asthma for more than 25 years and were non-smokers. Lung function was moderately impaired. Blood eosinophil count was≥150 cells/μL in 66% of patients,≥300 cells/μL in 34% of patients, and≥500 cells/μL in 12% of patients. One out of three patients was currently treated with omalizumab and 24% had maintenance oral corticosteroids. Asthma was poorly controlled with a negative impact on quality of life (ACQ≥1.5) in 67% of patients. In this population 40% of patients were eligible for omalizumab, 27% for mepolizumab and 2% for reslizumab.

CONCLUSIONS

These findings show that a considerable proportion of patients with severe asthma remain uncontrolled and are not eligible for any of the available biological treatments. This underlines the need for therapeutic innovations in this disease.

Precision medicine in asthma: the role of bronchial thermoplasty

PURPOSE OF REVIEW

The inflammatory makeup of severe asthma is heterogeneous. Identification of the predominant cellular endotype via biomarkers can aid in the selection of more advanced therapies. This review is clinically focused on how to use these biomarkers to help select between biologic agents and/or bronchial thermoplasty.

RECENT FINDINGS

Several Th2 biomarkers exist for the detection of eosinophilic disease; however, the best biomarker for clinical practice is debatable depending upon local resources. Currently, there are three federal drug agency-approved biologic agents (omalizumab, mepolizumab and reslizumab) to treat severe asthma with frequent exacerbations despite standard medical therapy. Several others are either in clinical trials or in the development phase for the treatment of eosinophilic asthma. To date, agents targeting neutrophilic inflammation have been largely unsuccessful. Bronchial thermoplasty has emerged as an option for the treatment of severe asthma.

SUMMARY

The appropriate selection of patients through the use of eosinophilic biomarkers has led to significant reductions in exacerbations with the use of mAb therapy. Bronchial thermoplasty has also shown reductions in asthma exacerbations and improved quality of life; however, it is unclear which patients may respond best to this intervention.

Pharmacokinetic/pharmacodynamic profile of reslizumab in asthma

INTRODUCTION

Allergic asthma is a Th2-driven inflammatory process characterized by the infiltration of eosinophils into the airways. IL-5 is a key trigger for eosinophil expansion and release from the bone marrow and plays a crucial role in the entire life span of eosinophils from differentiation to maturation and survival. IL-5 can be considered among the most obvious targets to selectively inhibit eosinophilic airway inflammation. Areas covered: The preclinical and clinical development of reslizumab, a humanized mAb against IL-5 that has been developed to block IL-5 bioactivity and reduce biologically available IL-5, are described with a particular focus on its pharmacodynamics (PK)/pharmacokinetic (PD) profile. Expert opinion: Although pivotal trials have documented that reslizumab can be recommended as add-on therapy for the treatment of patients with severe eosinophilic asthma, there is still important information that is lacking and some PK and PD properties of reslizumab are still not fully understood.