Successful pregnancy in the setting of eosinophil depletion by benralizumab

Safety of biologic agents for the management of rheumatic diseases during pregnancy

PURPOSE OF REVIEW

To discuss the current understanding regarding the use of biologic therapeutics in pregnancy.

RECENT FINDINGS

Our understanding of the mechanisms underlying the potential fetal and infant exposure to biologics as well as a growing body of empirical evidence from real world use of biologics in pregnancy have demonstrated that biologics are generally compatible preconception and during pregnancy. Long-term effects of exposure to biologic agents in utero are not known, but will be uncovered in time. Biosimilars, which are becoming more popular, may not always share the same safety profiles as their originators.

SUMMARY

Biologics have revolutionized the management of rheumatologic disease and ushered in a new era of clinical remission among patients. These agents, developed and introduced into clinical use at the beginning of the new millennium, are very potent, yet their efficacy in treating disease often in reproductive aged women, raises questions regarding their safety during pregnancy. These therapeutics can cause immunosuppression and can inhibit immunologic circuits that are not only involved in disease pathophysiology but hypothetically could impact the development of the fetal immune system. Reassuringly, biologics, typically antibodies or antibody-based proteins, are introduced to the fetus via the typical route of transplacental antibody transfer, and thus only begin to be transferred in appreciable amounts in the second trimester (after organogenesis). From theoretic and empirical standpoints, biologic use during pregnancy appears well tolerated for fetal development and to not substantially affect infant immune development.

Asthma in pregnancy: a review of recent literature

PURPOSE OF REVIEW

Asthma remains the most common respiratory disease in pregnancy. Identifying risk factors for asthma exacerbations during pregnancy is critical, as uncontrolled asthma can have detrimental effects for both mother and baby. In this review, we discuss recent literature exploring risk factors, fetal and maternal effects, and treatment options for asthma during pregnancy.

RECENT FINDINGS

Recent literature suggests that optimizing asthma during pregnancy improves outcomes for both mother and baby, as well as later in childhood. Current research affirms that the benefit of asthma medication use outweighs any potential risks related to the medications themselves. Limited information is available regarding the use of newer therapies such as biologics during pregnancy.

SUMMARY

Identifying risk factors for asthma exacerbations during pregnancy is critical to prevent adverse outcomes for both mother and baby. Recent evidence continues to affirm the safety of asthma medication use; more studies are needed regarding the use of new therapies during pregnancy.

French guidelines for the etiological workup of eosinophilia and the management of hypereosinophilic syndromes

Eosinophilic-related clinical manifestations are protean and the underlying conditions underpinning eosinophilia are highly diverse. The etiological workup of unexplained eosinophilia/hypereosinophilia can be challenging, and can lead sometimes to extensive, inappropriate, costly and/or invasive investigations. To date, guidelines for the etiological workup and management of eosinophilia are mainly issued by hematologists, and thus mostly cover the scope of clonal hypereosinophilic syndromes (HES). Here, thanks to an extensive literature review, and thanks to the joint work of a large panel of experts involving physicians from both adult and pediatric medicine and from various subspecialties (as well as a representative of a patients' association representative), we provide recommendations for both the step-by step diagnostic workup of eosinophilia (whether unexplained or within specific contexts) as well as the management and follow-up of the full spectrum of eosinophilic disorders (including clonal, reactive, lymphocytic and idiopathic HES, as well as single-organ diseases). Didactic prescription summaries intended to facilitate the prescription of eosinophil-targeted drugs are also provided, as are practical diagnostic and therapeutic algorithms. Lastly, this set of recommendations also includes a summary intended for general practitioners, as well as an overview of the therapeutic patient education program set up by the French reference center for HES. Further updates will be mandatory as new validated information emerges.

Monoclonal Antibodies (Biologics) for Allergic Rhinitis, Asthma, and Atopic Dermatitis During Pregnancy and Lactation

Asthma, allergic rhinitis, chronic urticaria, and atopic dermatitis are common diseases that affect hundreds of thousands of pregnant women each year. The authors discuss the use of biologics in women who are pregnant or lactating, indications, available safety information, and knowledge gaps. There are pregnant patients for which standard treatment is either inadequate or contraindicated; in those cases, monoclonal antibodies (biologics) should be considered despite the unknown risk to the fetus. In severe asthma, omalizumab is the best studied with reassuring available safety data. Insufficient safety data exist on mepolizumab, reslizumab, benralizumab, dupilumab, and tezepelumab use during pregnancy and lactation.

Expected impact of immunomodulatory agents during pregnancy: A newborn's perspective

The neonatal immune ontogeny begins during pregnancy to ensure that the neonate is well-suited for perinatal life. It prioritizes Th2/M2 and regulatory responses over Th/M1 activity to avoid excessive inflammatory responses and to ensure immune tolerance and homeostasis. Newborns also present increased Th17/Th22 responses providing effective anti-fungal immunity and mucosal protection. Intrauterine exposure to immune modulatory drugs with the placental transfer may influence the natural course of the fetal immune development. The vertical transfer of both biological therapy and small molecules begins during the first trimester through neonatal Fc receptor or placental diffusion, respectively, reaching its maximum transfer potential during the third trimester of pregnancy. Most of the biological therapy have a prolonged half-life in newborn's blood, being detectable in infants up to 12 months after birth (usually 6-9 months). The use of immunomodulators during pregnancy is gaining global interest. Current evidence mainly reports birth-related outcomes without exhaustive analysis of the on-target side effect on the perinatal immune system ontogeny, the infection risk, or the immune dysregulation. The present review will focus on: (1) the main characteristics of the perinatal immune system to understand its specific features and vulnerabilities to immune modulation; (2) the mechanisms of placental transfer of immunomodulators; and (3) the immune changes reported to date in newborns exposed to immunomodulators with emphasis on the current concerns and gaps in knowledge.

Risks and safety of biologics: A practical guide for allergists

Biologic agents are a rapidly expanding class of medications, and several options are now available for the management of allergic and immunologic disorders. The risks of biologic therapy need to be understood in order to adequately counsel patients and appropriately monitor for potential adverse events. We sought to provide a comprehensive review of the risks and adverse effects reported for the current FDA-approved biologics used in management of allergic and immunologic disorders, including omalizumab, benralizumab, dupilumab, mepolizumab, reslizumab, tezepelumab and tralokinumab. Our review focuses on the risk of hypersensitivity reactions, pregnancy-specific considerations, risk of infection and risk of malignancy. We also highlight drug-specific adverse events and unique safety issues identified in case reports.

Living without eosinophils: evidence from mouse and man

The enduring view of eosinophils, as immune effector cells whose primary function is host defence against infection by helminths and other microbial pathogens, sets the stage for a fundamental question regarding the safety of therapeutic eosinophil depletion. If eosinophils are significantly reduced or altogether depleted in an effort to alleviate the negative effects of tissue eosinophilia and eosinophilic inflammation in conditions such as asthma, COPD, chronic rhinosinusitis with nasal polyps, eosinophilic granulomatosis with polyangiitis and hypereosinophilic syndrome, would these patients become susceptible to infection or another illness? Development of mouse models in which the eosinophil lineage has been ablated, observations in patients naturally lacking eosinophils and data from studies of eosinophil-depleting medical therapies indicate that the absence of eosinophils is not detrimental to health. The evidence available to date, as presented in this review, supports the conclusion that even if certain homeostatic roles for the eosinophil may be demonstrable in controlled animal models and human in vitro settings, the evolution of the human species appears to have provided sufficient immune redundancy such that one may be hale and hearty without eosinophils.

Approach to the patient with suspected hypereosinophilic syndrome

Hypereosinophilic syndromes (HES) are a heterogenous group of rare disorders with clinical manifestations ranging from fatigue to life-threatening endomyocardial fibrosis and thromboembolic events. Given the broad differential diagnosis of HES, a comprehensive approach is needed to identify potential secondary (treatable) causes and define end-organ manifestations. Classification by clinical HES subtype is also useful in terms of assessing prognosis and guiding therapy. Corticosteroids remain the mainstay of initial therapy in the setting of acute, life-threatening PDGFR mutation-negative HES. Whereas the recent availability of eosinophil-targeted therapies with extraordinary efficacy and little apparent toxicity is changing the treatment paradigm, especially for idiopathic HES and overlap syndromes, questions remain unanswered regarding the choice of agent, impact of combination therapies, and long-term effects of eosinophil depletion. This review provides a case-based discussion of the differential diagnosis of HES, including the classification by clinical HES subtype. Treatment options are reviewed, including novel eosinophil-targeted agents recently approved for the treatment of HES and/or other eosinophil-associated disorders. Primary (myeloid) disorders associated with hypereosinophilia are not be addressed in depth in this review.

Safety of Biologics for Atopic Diseases During Pregnancy

The high prevalence of atopic diseases in women of childbearing age reveals the need to determine the safety of biologics during pregnancy. This review summarizes the effects of 7 Food and Drug Administration-approved biologics (omalizumab, mepolizumab, reslizumab, benralizumab, dupilumab, tezepelumab, and tralokinumab) on maternal and fetal outcomes. For this purpose, we reviewed English-language publications to investigate whether the use of biologics for atopic diseases during pregnancy increased the risk of preterm delivery, stillbirth, low birth weight, or congenital malformations. Most publications found were case reports, case series, or observational studies reporting outcomes in a total of 313 pregnancies. No randomized controlled studies were identified. We found that biologics do not seem to influence maternal or fetal outcomes. Indeed, worsening of the underlying atopic disease during pregnancy appears to be more detrimental to the viability of the pregnancy. Given the small sample size and scarcity of studies, future research should include prospective studies with comparable control groups without exposure to biologics and multicenter registries for long-term follow-up.

Treatment of allergic eosinophilic asthma through engineered IL-5-anchored chimeric antigen receptor T cells

Severe eosinophilic asthma (SEA) is a therapy-resistant respiratory condition with poor clinical control. Treatment efficacy and patient compliance of current therapies remain unsatisfactory. Here, inspired by the remarkable success of chimeric antigen receptor-based cellular adoptive immunotherapies demonstrated for the treatment of a variety of malignant tumors, we engineered a cytokine-anchored chimeric antigen receptor T (CCAR-T) cell system using a chimeric IL-5-CD28-CD3ζ receptor to trigger T-cell-mediated killing of eosinophils that are elevated during severe asthma attacks. IL-5-anchored CCAR-T cells exhibited selective and effective killing capacity in vitro and restricted eosinophil differentiation with apparent protection against allergic airway inflammation in two mouse models of asthma. Notably, a single dose of IL-5-anchored CCAR-T cells resulted in persistent protection against asthma-related conditions over three months, significantly exceeding the typical therapeutic window of current mAb-based treatments in the clinics. This study presents a cell-based treatment strategy for SEA and could set the stage for a new era of precision therapies against a variety of intractable allergic diseases in the future.

Eosinophils are an essential element of a type 2 immune axis that controls thymus regeneration

Therapeutic interventions used for cancer treatment provoke thymus damage and limit the recovery of protective immunity. Here, we show that eosinophils are an essential part of an intrathymic type 2 immune network that enables thymus recovery after ablative therapy. Within hours of damage, the thymus undergoes CCR3-dependent colonization by peripheral eosinophils, which reestablishes the epithelial microenvironments that control thymopoiesis. Eosinophil regulation of thymus regeneration occurs via the concerted action of NKT cells that trigger CCL11 production via IL4 receptor signaling in thymic stroma, and ILC2 that represent an intrathymic source of IL5, a cytokine that therapeutically boosts thymus regeneration after damage. Collectively, our findings identify an intrathymic network composed of multiple innate immune cells that restores thymus function during reestablishment of the adaptive immune system.

Effect of benralizumab in a patient with uncontrolled severe eosinophilic asthma and comorbid chronic rhinosinusitis with nasal polyps refractory to mepolizumab treatment

Severe eosinophilic asthma is associated with a high corticosteroid burden, particularly in patients with comorbid chronic sinusitis/nasal polyps. This case study reports a 33-year-old woman who presented to the severe asthma center with uncontrolled severe eosinophilic asthma and chronic rhinosinusitis with nasal polyps (CRSwNP). Despite maximized asthma treatment, including maintenance oral corticosteroids (OCS) for 7 years, the patient experienced one to two hospitalizations per year, had daily symptoms that substantially impacted her quality of life, and elevated type 2 inflammatory markers (blood eosinophils, 0.72 × 10⁹/L; fractional exhaled nitric oxide, 134 to 300 parts per billion). Her asthma worsened during her first pregnancy, in which she required five hospital admissions despite treatment with maintenance OCS. Mepolizumab treatment was commenced after pregnancy but showed limited efficacy (blood eosinophil levels up to 0.94 × 10⁹/L); treatment was discontinued because of a second pregnancy. The patient's asthma worsened and resulted in four hospitalizations and an increase in monthly OCS dose. Mepolizumab was recommenced after pregnancy, but her asthma remained uncontrolled, symptoms persisted, and one hospitalization and nine OCS courses were required. The patient was switched to benralizumab treatment when it became available. Although her CRSwNP symptoms remained, benralizumab treatment resulted in a marked improvement in asthma control, zero hospitalizations, and suppressed blood eosinophil levels. Notably, the patient was successfully weaned off maintenance OCS after >11 years of treatment. In summary, these findings support the use of benralizumab as a corticosteroid-sparing treatment option in difficult-to-treat severe eosinophilic asthma refractory to mepolizumab treatment.

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Benralizumab was a potent suppressor of blood eosinophils in this case study.

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Benralizumab resulted in a marked reduction in maintenance corticosteroid use.

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Benralizumab improved asthma exacerbations, control, and symptoms.

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Benralizumab had efficacy in severe asthma after unsuccessful mepolizumab treatment.

Recent Insights into the Management of Inflammation in Asthma

The present prevailing inflammatory paradigm in asthma is of T2-high inflammation orchestrated by key inflammatory cells like Type 2 helper lymphocytes, innate lymphoid cells group 2 and associated cytokines. Eosinophils are key components of this T2 inflammatory pathway and have become key therapeutic targets. Real-world evidence on the predominant T2-high nature of severe asthma is emerging. Various inflammatory biomarkers have been adopted in clinical practice to aid asthma characterization including airway measures such as bronchoscopic biopsy and lavage, induced sputum analysis, and fractional exhaled nitric oxide. Blood measures like eosinophil counts have also gained widespread usage and multicomponent algorithms combining different parameters are now appearing. There is also growing interest in potential future biomarkers including exhaled volatile organic compounds, micro RNAs and urinary biomarkers. Additionally, there is a growing realisation that asthma is a heterogeneous state with numerous phenotypes and associated treatable traits. These may show particular inflammatory patterns and merit-specific management approaches that could improve asthma patient outcomes. Inhaled corticosteroids (ICS) remain the mainstay of asthma management but their use earlier in the course of disease is being advocated. Recent evidence suggests potential roles for ICS in combination with long-acting beta-agonists (LABA) for as needed use in mild asthma whilst maintenance and reliever therapy regimes have gained widespread acceptance. Other anti-inflammatory strategies including ultra-fine particle ICS, leukotriene receptor antagonists and macrolide antibiotics may show efficacy in particular phenotypes too. Monoclonal antibody biologic therapies have recently entered clinical practice with significant impacts on asthma outcomes. Understanding of the efficacy and use of those agents is becoming clearer with a growing body of real-world evidence as is their potential applicability to other treatable comorbid traits. In conclusion, the evolving understanding of T2 driven inflammation alongside a treatable traits disease model is enhancing therapeutic approaches to address inflammation in asthma.

Lessons learned from targeting eosinophils in human disease

Eosinophils are a minor subset of the granulocyte lineage distinguished by their unique morphology, phenotype, cytoplasmic contents, and function. Evolutionarily, these are ancient cells whose existence has been conserved within vertebrates for millions of years, suggesting that their contribution to innate immunity and other pathologic and homeostatic responses are important to the host. Knowledge regarding the role of eosinophils in health and disease took a leap forward in 2004 with the creation of mouse strains deficient in eosinophils. This advance was paralleled in humans using pharmacology, namely, with the development of drugs capable of selectively reducing and sometimes even eliminating human eosinophils in those receiving these agents. As a result, a more definitive picture of what eosinophils do, and do not do, is emerging. This review will summarize recent advances in our understanding of the role of eosinophils in human disease by focusing mainly on data from clinical studies with anti-eosinophil therapies, even though the first of such agents, mepolizumab, was only approved in the USA in November 2015. Information regarding both efficacy and safety will be highlighted, and where relevant, intriguing data from animal models will also be mentioned, especially if there are conflicting effects seen in humans.