Triggers and Prodromal Symptoms of Angioedema Attacks in Patients With Hereditary Angioedema

Hereditary Angioedema: The Clinical Picture of Excessive Contact Activation

Hereditary angioedema is a rare, genetic disorder characterized by painful, debilitating and potentially life-threatening angioedema attacks in subcutaneous and submucosal tissue. While usually unpredictable, attacks can be provoked by a variety of triggers including physical injury and certain medication and are often preceded by prodromal symptoms. Hereditary angioedema has a profound influence on the patients' lives. The fundamental cause of hereditary angioedema in almost all patients is a mutation in the SERPING1 gene leading to a deficiency in C1-inhibitor. Subsequently, the contact activation cascade and kallikrein-kinin pathway are insufficiently inhibited, resulting in excessive bradykinin production triggering vascular leakage. While C1-inhibitor is an important regulator of the intrinsic coagulation pathway, fibrinolytic system and complement cascade, patients do not have an increased risk of coagulopathy, autoimmune conditions or immunodeficiency disorders. Hereditary angioedema is diagnosed based on C1-inhibitor level and function. Genetic analysis is only required in rare cases where hereditary angioedema with normal C1-inhibitor is found. In recent years, new, highly specific therapies have greatly improved disease control and angioedema-related quality of life. This article reviews the clinical picture of hereditary angioedema, the underlying pathophysiology, diagnostic process and currently available as well as investigational therapeutic options.

Hereditary angioedema: current therapeutic management and future approaches

PURPOSE OF REVIEW

The aim of this review is to provide an account of the focus of therapeutic strategies for hereditary angioedema (HAE), give a brief overview of those used in the past and set aside and toughly discuss those currently available as first line. Further research is ongoing and the future therapeutic approaches that are still in different phases of study will be reviewed as well.

RECENT FINDINGS

In the last two decades, major research advancements on HAE pathophysiology and management were made and numerous novel therapeutic options are now available. Compared to the past, drugs available nowadays are more effective, well tolerated, and possibly have a more convenient administration route. Moreover, numerous other drugs with innovative mechanisms of action are under development.

SUMMARY

HAE is a rare genetic disease that if not promptly treated, it can lead to death from asphyxiation. Furthermore, due to its disfiguring and painful manifestations, HAE implies an important burden on the quality of life. Recently, following great research progresses on HAE therapy, evidence-based guidelines on HAE management were released. The therapeutic landscape of HAE is still under florid development, and it is possible novel treatments will remarkably revolutionize HAE management in the future.

Case Report: Early presentation of hereditary angioedema symptoms in a 2-year-old boy

Hereditary angioedema (HAE) is a rare autosomal-dominant disease that is caused by a deficiency (type I) or dysfunction (type II) of the C1 inhibitor (C1-INH) due to a mutation in the SERPING1 gene, which codes for C1-INH. HAE with quantitatively and qualitatively normal C1-INH (type III) is often caused by a mutation in the F12 gene and no mutations in the SERPING1 gene and is a group of very rare diseases. The C1 esterase inhibitor (C1-INH) is a major regulator of critical enzymes that are implicated in the cascades of bradykinin generation, which increases vascular permeability and allows the flow of fluids into the extracellular space, resulting in angioedema. HAE clinically manifests with intermittent attacks of swelling of the subcutaneous tissue or submucosal layers of the respiratory and gastrointestinal tract. Young children are typically asymptomatic, and those affected by HAE usually present with symptoms in their early 20s. This article describes the case of very early onset of hereditary angioedema caused by C1-INH deficiency in a 2-year-old boy who experienced recurrent episodes of hand and abdominal angioedema not associated with urticaria or pruritus. His father suffered from severe HAE due to a de novo mutation of the SERPING1 gene. The same mutation of the SERPING1 gene was detected in his son at the age of 9-months prior to the occurrence of angioedema symptoms, during genetic family counseling. This paper advances the understanding of HAE and highlights the importance of genetic counseling of families with HAE to avoid late or inaccurate diagnosis and to initiate treatment on time.

Mast cell degranulation and bradykinin-induced angioedema - searching for the missing link

Initiation of the bradykinin generation cascade is responsible for the occurrence of attacks in some types of angioedema without wheals. Hereditary angioedema due to C1 inhibitor deficiency (HAE-C1-INH) is one such clinical entity. In this paper, we explore the existing evidence that mast cells (MCs) degranulation may contribute to the activation of the kallikrein-kinin system cascade, followed by bradykinin formation and angioedema. We present the multidirectional effects of MC-derived heparin and other polyanions on the major components of the kinin-kallikrein system, particularly on the factor XII activation. Although, bradykinin- and histamine-mediated symptoms are distinct clinical phenomena, they share some common features, such as some similar triggers and a predilection to occur at sites where mast cells reside, namely the skin and mucous membranes. In addition, recent observations indicate a high incidence of hypersensitivity reactions associated with MC degranulation in the HAE-C1-INH patient population. However, not all of these can be explained by IgE-dependent mechanisms. Mast cell-related G protein-coupled receptor-X2 (MRGPRX2), which has recently attracted scientific interest, may be involved in the activation of MCs through a different pathway. Therefore, we reviewed MRGPRX2 ligands that HAE-C1-INH patients may be exposed to in their daily lives and that may affect MCs degranulation. We also discussed the known inter- and intra-individual variability in the course of HAE-C1-INH in relation to factors responsible for possible variability in the strength of the response to MRGPRX2 receptor stimulation. The above issues raise several questions for future research. It is not known to what extent a prophylactic or therapeutic intervention targeting the pathways of one mechanism (mast cell degranulation) may affect the other (bradykinin production), or whether the number of mast cells at a specific body site and their reactivity to triggers such as pressure, allergens or MRGPRX2 agonists may influence the occurrence of HAE-C1-INH attacks at that site.

[Hereditary angioedema due to C1-inhibitor deficiency, a national disease management programme]

Hereditary angioedema (HAE) is a rare, painful, disabling and potentially fatal disease, where early diagnosis and effective treatment are critical. These Austrian guidelines for the diagnosis and management of HAE provide instructions and advice on the state of the art management of HAE in Austria in contrast to global guidelines, where the situation of all countries worldwide must be taken into account. Our goal is to help Austrian physicians to consider HAE as a differential diagnosis with corresponding symptoms, to make rational decisions for the diagnosis and management of HAE with C1-inhibitor deficiency (type 1 or type 2). The guidelines provide information on common and important clinical symptoms, diagnostic methods, treatment modalities, available HAE-specific medications in Austria and last but not least to motivate physicians to refer patients to HAE centers for confirmation of the diagnosis and adequate treatment decisions.

The multifactorial impact of receiving a hereditary angioedema diagnosis

Hereditary angioedema (HAE) is a rare, chronic, debilitating genetic disorder characterized by recurrent, unpredictable, and potentially life-threatening episodes of swelling that typically affect the extremities, face, abdomen, genitals, and larynx. The most frequent cause of HAE is a mutation in the serpin family G member 1 (SERPING1) gene, which either leads to deficient plasma levels of the C1-esterase inhibitor (C1-INH) protein (type I HAE-C1-INH) or normal plasma levels of dysfunctional C1-INH protein (type II HAE-C1-INH). Mutations in SERPING1 are known to be associated with dysregulation of the kallikrein-bradykinin cascade leading to enhancement of bradykinin production and increased vascular permeability. However, some patients present with a third type of HAE (HAE-nl-C1-INH) that is characterized by normal plasma levels and functionality of the C1-INH protein. While mutations in the factor XII, angiopoietin-1, plasminogen, kininogen-1, myoferlin, and heparan sulfate-glucosamine 3-O-sulfotransferase-6 genes have been identified in some patients with HAE-nI-C1-INH, genetic cause remains unknown in many cases with further research required to fully elucidate the pathology of disease in these patients. Here we review the challenges that arise on the pathway to a confirmed diagnosis of HAE and explore the multifactorial impact of receiving a HAE diagnosis. We conclude that it is important to continue to raise awareness of HAE because delays to diagnosis have a direct impact upon patient suffering and quality of life. Since many patients will seek help from hospitals during their first swelling attack it is vital that emergency department staff are aware of the different pathological pathways that distinguish HAE from other forms of angioedema to ensure that the most appropriate treatment is administered. As disease awareness increases, it is hoped that patients will be diagnosed earlier and that pre-authorization and insurance coverage of HAE treatments will become easier to obtain, ultimately reducing the burden of treatment for these patients and their caregivers.

Content validation and psychometric evaluation of the Angioedema Quality of Life Questionnaire for hereditary angioedema

BACKGROUND

There is considerable burden of illness in hereditary angioedema (HAE). However, instruments to assess health-related quality of life (HRQoL) in HAE are limited. The Angioedema Quality of Life Questionnaire (AE-QoL) was developed to measure HRQoL in patients with recurrent angioedema; the validity of the AE-QoL in patients with HAE is described.

METHODS

To identify disease-related experiences with a focus on the impact of HAE on HRQoL, interviews were conducted with a group of clinician experts and patients with HAE from Canada, France, Germany, Spain, the United Kingdom, and the United States, along with a targeted literature review. Concepts were mapped to the AE-QoL to assess item relevance, interpretation, and conceptual coverage. Cognitive interviews assessed item clarity and relevance. A psychometric validation was performed using data from a phase 3 trial.

RESULTS

Interviews were conducted with seven clinicians and 40 adult patients. Patients reported 35 unique impacts of HAE on their lives, the most frequent being on work/school, social relationships, physical activities, and emotions, particularly fear/worrying and anxiety. Saturation for these impacts was reached, and all concepts covered in the AE-QoL were reported during the interviews. Patients agreed that the questionnaire items and response options were clear and relevant, and the 4-week recall period was appropriate. The psychometric validation included data from 64 patients. For AE-QoL total scores, excellent internal consistency (Cronbach's alpha > 0.90), test-retest reliability (intraclass coefficient > 0.80), convergent validity with the Sheehan Disability Scale (r = 0.663), divergent validity with the EQ-5D-5L index (r = 0.292) and EQ-VAS (r = 0.337), and known-groups validity (p < 0.0001; ɳ2 = 0.56) were demonstrated.

CONCLUSIONS

Qualitative and psychometric analyses showed that the AE-QoL is a reliable and valid instrument for measuring HRQoL in adult patients with HAE from six countries.

Managing Diagnosis, Treatment, and Burden of Disease in Hereditary Angioedema Patients with Normal C1-Esterase Inhibitor

Hereditary angioedema (HAE) is a rare, chronic, and debilitating genetic disorder characterized by recurrent and unpredictable swelling episodes that primarily affect the subcutaneous and/or submucosal tissues of the extremities, larynx, face, abdomen, and genitals. Most cases of HAE are caused by mutations in the serpin family G member 1 gene (SERPING1), which encodes C1-esterase inhibitor (C1-INH) protein. Mutations in SERPING1 lead to deficient (type I HAE-C1-INH) or dysfunctional (type II HAE-C1-INH) C1-INH protein and subsequent dysregulation of the kallikrein-bradykinin cascade. However, some patients present with a third type of HAE (HAE-nI-C1-INH), which was first described in the year 2000 and is characterized by an absence of mutations in SERPING1. Although mutations in the coagulation factor XII, angiopoietin-1, plasminogen, kininogen-1, myoferlin, and heparan sulfate-glucosamine 3-O-sulfotransferase-6 genes have been identified in some patients with HAE-nI-C1-INH, genetic cause is still unknown in many cases, hindering full elucidation of the pathology of this HAE subtype. Diagnosis of HAE-nI-C1-INH is also further complicated by the fact that patients typically demonstrate normal plasma levels of C1-INH and complement component 4 protein and normal C1-INH functionality during laboratory analysis. Therefore, we review the challenges associated with diagnosing, treating, and living with HAE-nI-C1-INH. We conclude that raising awareness of the presenting features of HAE-nI-C1-INH within the clinical setting and among the general public is critical to aid earlier suspicion and diagnosis of the disease. Furthermore, adopting an individualized approach to HAE-nI-C1-INH treatment is essential to help address the current and significant unmet needs in this patient population.

Positive perception of COVID-19 vaccination in HAE: No significant impact of vaccination on disease course

Background: There are some adverse effects with coronavirus disease 2019 (COVID-19) vaccines, but the impact of COVID-19 vaccination on attacks in hereditary angioedema (HAE) is not well defined. Objective: We aimed to investigate the influence of COVID-19 vaccination on the course of HAE. Method: The COVID-19 vaccination status was determined in 140 adult patients with HAE. The number and severity of attacks recorded from patients' diaries were evaluated at four different periods, comprising 1 month before the first dose, the period between the first and the second doses of COVID-19 vaccine in all the patients, the period between the second dose and the third doses in those who received three doses, and 1 month after the last vaccination dose. The disease and attack severities were assessed with the disease severity score (DSS) and 10-point visual analog scale, respectively. The patients were divided into two main groups as group 1 (those who had at least two doses of COVID-19 vaccines [n = 114]) and group 2 (those who had no vaccination [n = 26]). Only Sinovac and Biontech, which were only approved in Turkey. Results: The mean ± standard deviation DSS was significantly higher in the patients who experienced an attack after vaccination within 48 hours (6.61 ± 1.88 versus 4.14 ± 1.69; p < 0.001). Long-term prophylaxis was less common in the patients with an increased number of attacks (n = 5 (27.8%) versus n = 54 (56.3%); p = 0.027). The number of patients with less than a high school education was higher in group 2 (n = 23 [88.5%]) than in group 1 (n = 26 [3.1%]) (p < 0.001). The number of patients who had concerns about the triggering of a vaccine-induced HAE attack or about the possible vaccine adverse effects was higher in group 2 (n = 26 [100%]) than in group 1 (n = 74 [64.9%]). Conclusion: It seems that COVID-19 vaccination does not increase HAE attacks regardless of the type of the vaccines. We recommend that HAE activity should be under control before COVID-19 vaccination, and the patients should be well informed about the safety of the vaccines.

Shared decision-making in the management of hereditary angioedema: An analysis of patient and physician perspectives

Background: Hereditary angioedema (HAE) is a rare genetic disorder characterized by recurrent, localized episodes of edema. Current treatment guidelines highlight the importance of shared decision-making (SDM) during implementation of HAE management plans. Objective: To determine what constitutes a successful SDM approach in HAE management. Method: Qualitative telephone interviews, which lasted ∼1 hour, were conducted with four HAE physicians and four patients from the APeX-S trial. The physicians were asked to describe the structure and/or content of typical HAE prophylaxis consultations and factors to consider when selecting medications for long-term treatment. Insights from these interviews were used to develop an SDM process diagram. The patients were interviewed to assess how closely the diagram fit their perspectives on the HAE consultation and their involvement in decisions that concerned their care. Interview transcripts were assessed by the interviewer to determine the degree of SDM involvement in each consultation by using qualitative criteria from the literature. Results: Two physicians followed a high-SDM format, and one physician used a "blended" approach. The fourth physician followed a standard (low SDM) format. A successful SDM approach was found to require pre-visit planning, a commitment on behalf of the physician to use SDM methods to learn more about the patient, and empowerment of the patient to reflect on and vocalize his or her preferences and/or needs. Patients engaged in SDM were more likely to proactively request a treatment switch. Conclusion: The adoption of validated HAE-specific treatment decision aids, as well as measures to change the mindsets of patients and physicians, may facilitate successful implementation of SDM in HAE.Clinical Trial Registration: The APeX-S trial was registered with clinicaltrials.gov (NCT03472040).

The Icatibant Outcome Survey: 10 years of experience with icatibant for patients with hereditary angioedema

In patients with hereditary angioedema (HAE), bradykinin causes swelling episodes by activating bradykinin B₂ receptors. Icatibant, a selective bradykinin B₂ receptor antagonist, is approved for on-demand treatment of HAE attacks. The Icatibant Outcome Survey (IOS; NCT01034969) is an ongoing observational registry initiated in 2009 to monitor effectiveness/safety of icatibant in routine clinical practice. As of March 2019, 549 patients with HAE type 1 or 2 from the IOS registry had been treated, for 5995 total attacks. This article reviews data published from IOS over time which have demonstrated that effectiveness of icatibant in a real-world setting is comparable to efficacy in clinical trials; one dose is effective for the majority of attacks; early treatment (facilitated by self-administration) leads to faster resolution and shorter attack duration; effectiveness/safety of icatibant has been shown across a broad range of patient subgroups, including children/adolescents and patients with HAE with normal C1 inhibitor levels; and tolerability has been demonstrated in patients aged ≥65 years. Additionally, this review highlights how IOS data have provided valuable insights into patients' diagnostic journeys and treatment behaviors across individual countries. Such findings have helped to inform clinical strategies and guidelines to optimize HAE management and limit disease burden. This research was sponsored by Takeda Development Center Americas, Inc. Takeda Development Center Americas, Inc., provided funding to Excel Medical Affairs for support in writing and editing this manuscript.

The international WAO/EAACI guideline for the management of hereditary angioedema - The 2021 revision and update

Hereditary Angioedema (HAE) is a rare and disabling disease for which early diagnosis and effective therapy are critical. This revision and update of the global WAO/EAACI guideline on the diagnosis and management of HAE provides up-to-date guidance for the management of HAE. For this update and revision of the guideline, an international panel of experts reviewed the existing evidence, developed 28 recommendations, and established consensus by an online DELPHI process. The goal of these recommendations and guideline is to help physicians and their patients in making rational decisions in the management of HAE with deficient C1-inhibitor (type 1) and HAE with dysfunctional C1-inhibitor (type 2), by providing guidance on common and important clinical issues, such as: 1) How should HAE be diagnosed? 2) When should HAE patients receive prophylactic on top of on-demand treatment and what treatments should be used? 3) What are the goals of treatment? 4) Should HAE management be different for special HAE patient groups such as children or pregnant/breast feeding women? 5) How should HAE patients monitor their disease activity, impact, and control? It is also the intention of this guideline to help establish global standards for the management of HAE and to encourage and facilitate the use of recommended diagnostics and therapies for all patients.

How satisfactory is on-demand icatibant from the patients' perspective in real life?

Background: Patients' satisfaction is important for the success of the management of chronic diseases. Objective: Our aim was to evaluate the satisfaction level of the patients with hereditary angioedema (HAE) for icatibant treatment. Methods: Patients with HAE C1 esterase inhibitor (C1-INH) were evaluated by using a questionnaire that included details of their icatibant-treated attacks. Patients' demographic and clinical features were collected from their medical records and personal attack diaries. The visual analog scale was used for determining the attack severity. Results: Of the total 161 patients with HAE C1-INH, 91% had HAE type I and were included in the study. Patients reported a median (interquartile range [IQR]) attacks of 2 (0.5-3) per month and 16 (4.5-36) attacks per year. The median (IQR) frequency of attacks treated with icatibant was 6 (0-20) per year. The mean ± standard deviation (SD) duration of treatment with icatibant was 3 ± 2.3 years. The self-administration rate was 91.3%. The mean ± SD time to administration and time to onset of symptom resolution were 1.6 ± 1.1 hours and 1.7 ± 1.3 hours, respectively. There was a correlation between the time to administration and time to onset of symptom resolution (r = 0.566; p < 0.0001). A total of 125 patients (77%) reported that they were very satisfied or satisfied with icatibant. No correlation was observed between the satisfaction level and the attack sites; however, the patients with more severe attacks were more satisfied with icatibant (p < 0.0001). A total of 52 patients reported 74 mild local reactions. Systemic reactions were not observed. Conclusion: The current real-life study showed that icatibant was safe and effective. Moreover, the patients' satisfaction level with icatibant was high. We believe that the availability of icatibant should be encouraged during HAE attacks because it enables patients to be more involved in their disease management.

Specific Targeting of Plasma Kallikrein for Treatment of Hereditary Angioedema: A Revolutionary Decade

Hereditary angioedema (HAE) is a rare, chronic, genetic disease that presents with nonpruritic angioedema of the face, extremities, airway (can be life-threatening), genitourinary system, and abdomen. These symptoms can significantly impair daily activities. Hereditary angioedema is classified into HAE owing to a deficiency of functional C1INH (HAE-C1INH) or HAE with normal C1INH (HAE-nl-C1INH). Both type I and II HAE-C1INH result from inherited or spontaneous mutations in the SERPING1 gene, which encodes for C1INH. These mutations result in C1INH dysfunction, leading to uncontrolled plasma kallikrein activity with excessive bradykinin production. Bradykinin receptor activation leads to vasodilation, increased vascular permeability, and smooth muscle contractions, resulting in submucosal angioedema through fluid extravasation. Hereditary angioedema nl-C1INH is caused by either a known or unknown genetic mutation. The underlying mechanism of HAE-nl-C1INH is less well understood but is thought to be related to bradykinin signaling. Plasma kallikrein inhibitors have been developed to inhibit the kallikrein-kinin pathway to prevent (prophylactic) and treat on-demand (acute) HAE attacks. Several of these medications are delivered through subcutaneous or intravenous injection, although new and emerging therapies include oral formulations. This article provides a historical review and describes the evolving landscape of available kallikrein inhibitors to treat HAE-C1INH.

The international WAO/EAACI guideline for the management of hereditary angioedema-The 2021 revision and update

Hereditary angioedema (HAE) is a rare and disabling disease for which early diagnosis and effective therapy are critical. This revision and update of the global WAO/EAACI guideline on the diagnosis and management of HAE provides up-to-date guidance for the management of HAE. For this update and revision of the guideline, an international panel of experts reviewed the existing evidence, developed 28 recommendations, and established consensus by an online DELPHI process. The goal of these recommendations and guideline is to help physicians and their patients in making rational decisions in the management of HAE with deficient C1 inhibitor (type 1) and HAE with dysfunctional C1 inhibitor (type 2), by providing guidance on common and important clinical issues, such as: (1) How should HAE be diagnosed? (2) When should HAE patients receive prophylactic on top of on-demand treatment and what treatments should be used? (3) What are the goals of treatment? (4) Should HAE management be different for special HAE patient groups such as children or pregnant/breast-feeding women? and (5) How should HAE patients monitor their disease activity, impact, and control? It is also the intention of this guideline to help establish global standards for the management of HAE and to encourage and facilitate the use of recommended diagnostics and therapies for all patients.

Hereditary angioedema due to C1 inhibitor deficiency: real-world experience from the Icatibant Outcome Survey in Spain

Background

The Icatibant Outcome Survey (IOS) is an international registry monitoring the use of icatibant, a bradykinin B2 receptor antagonist indicated for the acute treatment of hereditary angioedema (HAE) attacks. Our goal was to assess disease characteristics and icatibant treatment outcomes in patients with HAE due to C1 inhibitor deficiency (HAE type 1 or 2 (HAE-1/2)) from Spain relative to other countries participating in IOS.

Methods

Descriptive retrospective analyses of data are reported from 10 centers in Spain vs 51 centers in 12 other participating countries (July 2009 to January 2019).

Results

No meaningful differences were identified between patients in Spain (n = 119) and patients across other countries (n = 907) regarding median age at symptom onset (15.0 vs 12.0 years) or diagnosis (22.3 vs 20.5 years). Overall HAE attack rates (total attacks/total years of follow-up) were 2.66 in Spain and 1.46 across other countries. Patients in Spain reported fewer severe/very severe HAE attacks before treatment (41.0% vs 45.9%; P < 0.0001) and, for icatibant-treated attacks, longer median time to treatment (2.9 vs 1.0 h), time to attack resolution (18.0 vs 5.5 h), and total attack duration (24.6 vs 8.0 h). Use of androgens for long-term prophylaxis was higher in Spain (51.2% vs 26.7%).

Conclusion

Patients with HAE-1/2 in Spain reported fewer severe/very severe attacks, administered icatibant later, and had longer-lasting attacks than did patients across other countries in IOS. These differences may indicate varying disease management practices (e.g., delayed icatibant treatment) and reporting. Efforts to raise awareness on the benefits of early on-demand treatment may be warranted.

Trial registration: NCT01034969.

Considerations for transition from subcutaneous to oral prophylaxis in the treatment of hereditary angioedema

BACKGROUND

Hereditary angioedema (HAE) is a rare genetic disorder characterized by unpredictable localized episodes of edema, which is frequently managed with long-term prophylactic medications. Until recently, long-term prophylaxis has predominantly required regular intravenous or subcutaneous administration, however the recent approval of berotralstat (Orladeyo™) offers an orally administered prophylactic which may be associated with a lower burden of treatment compared to injectable options for some patients.

CASE PRESENTATION

This report describes four participants in the APeX-S trial who transitioned from subcutaneously administered lanadelumab (Takhzyro®) to daily oral berotralstat for long-term HAE prophylaxis. Lanadelumab dosing continued after berotralstat commencement in all patients and was tapered before discontinuation in three of the four patients. No substantial increases in HAE attack rates were observed after the transition to berotralstat monotherapy. One patient experienced a treatment-related adverse event (dyspepsia), which was mild and self-resolving.

CONCLUSIONS

All four patients described in this case series successfully transitioned from lanadelumab to berotralstat monotherapy for long-term prophylaxis without significant complications and without the use of a complex transition protocol. The decision to transition to berotralstat monotherapy and how the transition should be achieved was discussed between patient and physician, ensuring that the comfort and perspectives of the patients were considered during the treatment transition. This report highlights the importance of individualization of HAE management plans to address both the disease and treatment burdens of HAE, and thus to provide the best possible quality of life for each patient.

Variability of disease activity in patients with hereditary angioedema type 1/2: longitudinal data from the Icatibant Outcome Survey

BACKGROUND

Hereditary angioedema due to C1 inhibitor deficiency (HAE-1/2) is a chronic and debilitating disease. The unpredictable clinical course represents a significant patient burden.

OBJECTIVE

To analyse longitudinal registry data from the Icatibant Outcome Survey (IOS) in order to characterize temporal changes in disease activity in patients with HAE-1/2.

METHODS

Icatibant Outcome Survey (NCT01034969) is an international observational registry monitoring the clinical outcomes of patients eligible for icatibant treatment. The current analyses are based on data collected between July 2009 and July 2019. Retrospective data for attacks recorded in the 12 months prior to IOS enrolment and for each 12-month period up to 7 years were analysed.

RESULTS

Included patients reported angioedema attacks without long-term prophylaxis (LTP; n = 315) and with LTP (n = 292) use at the time of attack onset. Androgens were the most frequently used LTP option (80.8%). At the population level, regardless of LTP use, most patients (52-80%) reporting <5 attacks in Year 1 continued experiencing this rate; similarly, many patients (25-76%) who reported high attack frequency continued reporting ≥10 attacks/year. However, year on year, 31-51% of patients experienced notable changes (increase/decrease of ≥5 attacks) in annual attack frequency. Of patients who reported an absolute change of ≥10 attacks from Year 1 to 2, 17-50% continued to experience a change of this magnitude in subsequent years.

CONCLUSION

At the population level, attack frequency was generally consistent over 7 years. At the small group level, 28.8-34.5% of patients reported a change in attack frequency of ≥5 attacks from Year 1 to Year 2; up to half of these patients continued to experience this magnitude of variation in disease activity in later years, reflecting high intra-patient variability.

Differences and Similarities in the Mechanisms and Clinical Expression of Bradykinin-Mediated vs. Mast Cell-Mediated Angioedema

Angioedema (AE), transient localized swelling due to extravasated fluid, is commonly classified as mast cell mediator-induced, bradykinin-mediated or of unknown cause. AE often occurs more than once, and it is these recurrent forms of AE that are challenging for patients and physicians, and they are the ones we focus on and refer to as AE in this review. Since effective treatment depends on the causative mediator, reliable and early diagnosis is essential. Although their clinical presentations bear similarities, many forms of angioedema exhibit specific patterns of clinical appearance or disease history that may aid in diagnosis. Here, we describe the most common differences and similarities in the mechanisms and clinical features of bradykinin-mediated and mast cell mediator-induced types of angioedema. We first provide an overview of the diseases that manifest with mast cell mediator-induced versus bradykinin-mediated angioedema as well as their respective underlying pathogenesis. We then compare these diseases for key clinical features, including angioedema location, course and duration of swelling, attack frequency, prevalence and relevance of prodromal signs and symptoms, triggers of angioedema attacks, and other signs and symptoms including wheals, age of onset, and duration. Our review and comparison of the clinical profiles of different types of angioedema incorporate our own clinical experience as well as published information. Our aim is to highlight that mast cell mediator-induced and bradykinin-mediated angioedema types share common features but are different in many aspects. Knowledge of the differences in underlying pathomechanisms and clinical profiles between different types of angioedema can help with the diagnostic approach in affected patients and facilitate targeted and effective treatment.

Impact of anxiety, stress and depression related to COVID-19 pandemic on the course of hereditary angioedema with C1-inhibitor deficiency

BACKGROUND

Hereditary angioedema (HAE) attacks can be provoked with psychological factors. The aim of this study was to assess the effects of anxiety, depression and stress related to COVID-19 pandemic on disease activity of HAE patients during the quarantine period (QP) and the return to normal period (RTNP).

METHODS

This study was conducted between March 2020 and September 2020 in four allergy centres. Demographic, clinical features and mental health status were evaluated in QP (from March to the beginning of June) and RTNP (from June to the beginning of September) applied by the government. The 10-point visual analogue scale (VAS10) was used to define the severity of HAE attacks. Depression, Anxiety and Stress Scales-21 (DASS-21) and Fear of COVID-19 (FC-19) scale were performed to assess mental health status.

RESULTS

139 HAE patients were included in the study. In QP, median attack numbers and median VAS10 scores were 5 (min-max: 0-45) and 6 (min-max: 0-10), respectively. HAE attack numbers, DASS-21 stress, anxiety, depression and total DASS-21 scores, and FC-19 scores were higher in QP than RTNP (p = 0.001, p < 0.001, p = 0.001, p < 0.001, p < 0.001, p < 0.001, respectively). However, there was no difference in attack severity scores between the two periods (p > 0.05).

CONCLUSIONS

This study revealed that the restriction measures during COVID-19 outbreak cause an increase in the number of HAE attacks in relation to anxiety, depression, stress and fear of COVID-19 pandemic. Therefore, it is important to provide psychological support to HAE patients during the pandemic.

Triggers of Exacerbation in Chronic Urticaria and Recurrent Angioedema-Prevalence and Relevance

Patients with urticaria and angioedema often have triggers that cause an outbreak or a swelling episode or worsen their chronic condition. Exploring these factors with each patient may result in better understanding and control of their disease. Patients should be advised to avoid known triggers, if feasible, or prepare to prevent or control an exacerbation with appropriate pretreatment if avoidance is not possible. In this review, we describe and discuss a variety of factors for which there is evidence that they cause or exacerbate chronic spontaneous urticaria and angioedema. These potentially exacerbating factors include drugs, food additives, and naturally occurring pseudoallergens, mental stress, and trauma.

The importance of recognizing and managing a rare form of angioedema: hereditary angioedema due to C1-inhibitor deficiency

The majority of angioedema cases encountered in clinical practice are histamine-mediated (allergic); however, some cases are bradykinin-related (non-allergic) and do not respond to standard anti-allergy medications. Among bradykinin-related angioedema, hereditary angioedema (HAE) is a rare, but chronic and debilitating condition. The majority of HAE is caused by deficiency (type 1) or abnormal function (type 2) of the naturally occurring protein, C1-inhibitor (C1-INH)-a major inhibitor of proteases in the contact (kallikrein-bradykinin cascade), fibrinolytic pathway, and complement systems. Failure to recognize HAE and initiate appropriate intervention can lead to years of pain, disability, impaired quality of life (QoL) and, in cases of laryngeal involvement, it can be life-threatening. HAE must be considered in the differential diagnosis of non-urticarial angioedema, particularly for patients with a history of recurrent angioedema attacks, family history of HAE, symptom onset in childhood/adolescence, prodromal signs/symptoms before swellings, recurrent/painful abdominal symptoms, and upper airway edema. Management strategies for HAE include on-demand treatment for acute attacks, short-term prophylaxis prior to attack-triggering events/procedures, and long-term or routine prophylaxis for attack prevention. Patients should be evaluated at least annually to assess need for routine prophylaxis. HAE specific medications like plasma-derived and recombinant C1-INH products, kallikrein inhibitors, and bradykinin B2 receptor antagonists, have improved management of HAE. While the introduction of intravenous C1-INH represented a major breakthrough in routine HAE prophylaxis, some patients fail to achieve adequate control and others have psychological barriers or experience complications related to intravenous administration. Subcutaneous (SC) C1-INH, SC monoclonal antibody (mAb)-based therapies, and an oral kallikrein inhibitor offer effective alternatives for HAE attack prevention and may facilitate self-administration. HAE management should be individualized, with QoL improvement being a key goal. This can be achieved with broader availability of existing options for routine prophylaxis, including greater global availability of C1-INH(SC), mAb-based therapy, oral treatments, and multiple on-demand therapies.

Etiology and predictors of cluster attacks of hereditary angioedema that recur despite pharmaceutical treatment

Introduction: Hereditary angioedema (HAE) is a disease that leads to recurrent swelling of the skin and mucous membranes, including the upper airway tract. Apart from being deadly, these attacks can be debilitating, which leads to a poor quality of life in patients. Clinicians are occasionally confronted with patients who have recurrent attacks despite treatment with C1 esterase inhibitor concentrate or β₂-receptor antagonists. The goal of this study was to investigate repeated attacks that occur 48 hours to 7 days ("cluster attacks") after treatment, to determine why they occur and the factors that may be associated with them, and thus to prevent their occurrence. Methods: We conducted a multicenter mixed retrospective-prospective study with data acquired from all documented attacks in our patients with collective (n = 132) between 2015 and 2018. Results: Eighty-five percent (n = 132) of our total patient collective (N = 156) agreed to participate in the study. Nine percent of these patients (n = 12) had cluster attacks, with a total of 48 cluster attacks. The data procured from the patients were mixed retrospective-prospective. Approximately 72% of all the cluster attacks were caused by exogenous stimuli (41% due to psychological stress, 29% due to physical stimuli, and 2% due to menstruation). Cluster attacks occurred in 7% of the patients who received prophylactic therapy in comparison with 12.5% of patients who received on-demand therapy. Cluster attacks comprised 48.4% of all the attacks that patients with cluster-attacks (n= 9) experienced. In addition, the patients who were underdosing their C1 esterase inhibitor treatment had cluster attacks more often. A lower "time to repeated attack" was seen in the patients who received on-demand therapy compared with those who received prophylactic therapy. Discussion: The percentage of the patients who had attacks as a result of exogenous triggers was higher in the cluster-attack group (70.5%) compared with the general HAE population (30-42%). Repeated attacks, therefore, were strongly associated with external triggers. The patients who received prophylactic treatment and who experienced cluster attacks were highly likely to have been underdosing, which may explain the repeated attacks despite treatment. In the patients prone to cluster attacks, prophylaxis should be considered.

Psychosocial burden of type 1 and 2 hereditary angioedema: a single-center Canadian cohort study

BACKGROUND

Hereditary angioedema (HAE) is a rare but serious disorder associated with a multifaceted burden of illness including a high prevalence of psychiatric symptoms and impaired health-related quality of life (HRQoL). Despite recent efforts to clarify the psychosocial implications of HAE, important gaps still remain. The aim of this study was to characterize the psychosocial burden associated with HAE types 1 and 2.

METHODS

Type 1 or 2 HAE patients (n  =  17), aged 19 years or older, completed the Depression, Anxiety, Stress Scale (DASS-21) and the DSM-5 cross cutting measures to identify psychiatric symptomatology, Angioedema Quality of Life Questionnaire (AE-QoL) and the Short-Form 36-Item Health Survey version 2 (SF-36v2) to assess disease-related and generic HRQoL respectively, and the Work Productivity and Activity Impairment Questionnaire (WPAI) to measure impact on work productivity and daily activities. Data analyses were conducted using SPSS statistical software (Version 25.0; IBM, Armonk, NY). Descriptive statistics were used to summarize continuous demographics and clinical characteristics and outcomes of interest while frequency distributions were used for categorical variables. T tests were used to compare SF-36v2 domain scores to Canadian norms and sex differences in scale scores.

RESULTS

Depression [DASS-21 score  =  6.8  ±  10.2; n  =  12 (71%)] anxiety [DASS-21 score  =  6.2  ±  8.2; n  =  13 (76%)] and stress [DASS-21 score  =  10  ±  10.2; n  =  13 (76%)] were prevalent. Other psychiatric symptoms warranting inquiry included mania (n  =  14, 82.4%), anger (n  =  14, 82.4%), sleep disturbances (n  =  13, 76.5%), somatic symptoms (n  =  11, 64.7%) and impaired personality functioning (n  =  9, 52.9%). Mean AE-QoL score was 39  ±  18.2. Mean SF-36v2 domain scores were significantly lower than Canadian normative data for the entire sample (p  <  0.05). Impairment in work productivity was minimal; mean activity impairment was 20.6%  ±  21.1% [n  =  11 (64.7%)]. Female participants reported significantly greater HAE-related stress [DASS; t(15)  =   - 2.2, p  =  0.04], greater HAE-related fears [AEQoL; t(5.6)  =   - 2.7, p  =  0.04), and lower SF-36v2 domain scores than male patients.

CONCLUSIONS

Study findings offer specific, valuable insight into the psychosocial burden of HAE with the potential to improve clinical management of HAE. Best practices for effective management of HAE should include providing holistic care to address the psychosocial and mental health of HAE patients.

Assessment of disease activity and quality of life in patients with recurrent bradykinin-mediated versus mast cell-mediated angioedema

Objective

Recurrent Angioedema (RAE) is characterized by sudden swelling of mucosal surfaces or deep dermis and is either mast cell-(MMAE) or bradykinin-mediated (BMAE). How patients with BMAE and MMAE differ in terms of disease activity and impact remains largely unknown. Here, we determined validity, reliability, and sensitivity to change of Turkish versions of angioedema activity score (AAS) and quality of life questionnaire (AE-QoL) and used both instruments to investigate and compare patients with BMAE and MMAE.

Methods

Turkish versions of AAS28 and AE-QoL were applied to 94 patients with RAE (18–72 years). Patients’ global self-assessment of QoL (PGA-QoL), disease activity (PGA-DA-VRS, PatGA-DA-VAS), and 12-Item-Short Form Survey were used at week 4 (visit 2), and week 8 (visit 3). Demographic characteristics, clinical features, and AAS28 and AE-QoL values were compared between 31 patients with BMAE and 63 patients with MMAE.

Results

Turkish AAS28 and AE-QoL showed excellent internal consistency, high reproducibility and known-groups validity. Compared to patients with MMAE, BMAE patients were younger (34.6 ± 10.7 vs. 40.7 ± 13.3 years), had longer disease duration (236 ± 178 vs. 51 ± 78 months), high prevalence of family history (63% vs 14%), longer duration of attacks (65 ± 20 vs. 40 ± 25 h), and they were more commonly affected by upper airway angioedema (70% vs 23%). Disease activity (AAS28) was lower (29.3 ± 24.6 vs 55.2 ± 52.9), but AE-QoL was higher (44.2 ± 16.1 vs 34.5 ± 22.5) in BMAE patients as compared to MMAE patients.

Conclusions

Patients with BMAE and MMAE have distinct disease characteristics. Recurrent bradykinin-mediated angioedema impacts quality of life more than mast cell-mediated angioedema. The discriminating characteristics of patients with BMAE and MMAE may help to improve the diagnosis and management of patients with RAE.

Recombinant human C1 esterase inhibitor for hereditary angioedema attacks: A European registry

Background

Hereditary angioedema (HAE) due to C1 esterase inhibitor deficiency (C1-INH-HAE) is characterized by recurrent swelling attacks. A European treatment registry was established to review the adverse event profile and efficacy of recombinant human C1 esterase inhibitor (rhC1-INH) for HAE attacks.

Methods

Individuals with C1-INH-HAE were enrolled following a decision to treat with rhC1-INH and provision of written informed consent. Medical history and baseline HAE information were collected at screening. Healthcare providers entered data on HAE attacks, response to treatment, and adverse events using a web-based questionnaire.

Results

From July 1, 2011, through December 1, 2019, 71 patients with C1-INH-HAE (30 male/41 female; mean age, 47.3 years; age range, 19–78 years) in 9 countries reported 2356 attacks and were treated with rhC1-INH. Before registry entry, patients, including 20 (28.2%) who were on maintenance therapy/prophylaxis at registry enrollment, experienced a mean of 25 HAE attacks per year (median, 16 [range, 0–185]). Most treated HAE attacks were abdominal (46.1%), followed by peripheral (38.3%), oro-facial-pharyngeal (14.8%), urogenital (3.2%), and laryngeal (2.6%). The mean rhC1-INH dose was 3307 U (43.3 U/kg). Patients reported symptom improvement within 4 h for 97.8% of attacks (2305/2356) with rhC1-INH; most attacks (99.8%; 2351/2356) required only 1 dose. Five attacks were treated with a second dose (total rhC1-INH dose administered for attack, 4200 U). No hypersensitivity, thrombotic/thromboembolic events, or drug-related serious adverse events were reported.

Conclusion

The rhC1-INH treatment registry provided real-world data on the treatment of 2356 HAE attacks that were consistent with clinical trial data of rhC1-INH in patients with C1-INH-HAE.

Unnecessary Abdominal Surgeries in Attacks of Hereditary Angioedema with Normal C1 Inhibitor

Hereditary angioedema (HAE) is an autosomal dominant disease mostly due to the deficiency of C1 inhibitor (C1-INH). HAE with normal C1-INH was first described in 2000 and associated with mutations in the coagulation factor XII in 2006. Both diseases are associated with high bradykinin production, resulting in increased vascular permeability. Gastrointestinal edema due to HAE can be misdiagnosed as acute abdomen and unnecessary surgical procedures may be performed. The present study evaluates the prevalence of surgical procedures and/or acute abdomen in HAE patients with the coagulation factor XII mutation. It is a retrospective study where patients were diagnosed with recurrent angioedema without urticaria, normal C1-INH levels, and positive family history of angioedema. All patients were evaluated for the known mutations located at exon 9 of the F12 gene. Medical records were evaluated and questionnaires were applied to 52 patients with normal C1-INH levels (age range 13-76 years; 47/52, 90.38% women; 5/52, 9.61% men). F12 mutation was present in 32/52 patients (61.5%). Acute abdominal pain was diagnosed in 16/52 (30.76%) patients, appendicitis in 9/16 (56.2%), and undetermined diagnosis in 7/16 (43.7%). Among patients diagnosed with acute abdominal pain, 13/16 (81.2%) underwent surgery and 3/16 (18.7%) improved without surgical intervention. We conclude that many HAE patients with coagulation factor XII mutation were misdiagnosed with acute abdomen and subjected to unnecessary invasive procedures. It is critical to disseminate information about this rare mutation in patients with otherwise normal C1-INH activity, in order to speed up diagnosis and avoid misconduct.

The Enigma of Prodromes in Hereditary Angioedema (HAE)

A prodrome is a premonitory set of signs and symptoms indicating the onset of a disease. Prodromes are frequently reported by hereditary angioedema (HAE) patients, antedating attacks by a few hours or even longer. In some studies, high incidence of prodromes was reported by patients, with considerable number being able to predict oncoming attacks. Regrettably, prodromes have never received a consensual definition and have not been properly investigated in a systematic fashion. Therefore, their nature remains elusive and their contribution to the diagnosis and treatment of disorders is uncertain. The term "prodrome," as used in various pathologies, denotes different meanings, timing, and duration, so it may not be equally suitable for all clinical situations. Perception of a prodrome is unique for each individual patient depending on self-experience. As modern drugs delegate the administration decision to the patients, early detection of a developing attack may help mitigate its severity and allow deployment of appropriate therapy. New diagnostic instruments were recently developed that can assist in defining the attributes of prodromes and their association with attacks. We will review the prodrome phenomenon as exhibited in certain clinical situations, with an emphasis on prodromes of HAE.

Androgen use in hereditary angioedema: A critical appraisal and approaches to transitioning from androgens to other therapies

Background: Hereditary angioedema (HAE) is a rare genetic disorder clinically characterized by recurrent attacks of subcutaneous and mucosal swelling. Attenuated androgens have been a prophylactic treatment option to reduce the frequency of HAE attacks for > 4 decades. However, the advent of effective on-demand treatments and highly effective, more tolerable, long-term prophylactic therapies has led to a decline in the use of attenuated androgens for the management of HAE in regions where newer therapies are available. A consensus about the best approach for discontinuing or tapering off attenuated androgen therapy does not exist. Objective: To develop a consensus on androgen tapering for patients with HAE. Methods: We sent an open-ended survey about androgen tapering to 21 physicians who treat HAE, 12 of whom responded. We reviewed the collective experience of the participating physicians in combination with results from a literature review on the topic. Results: The survey and literature review underscored potential concerns related to rapid androgen withdrawal in patients with HAE, including physician and patient concerns that the frequency and severity of attacks would abruptly worsen. In addition, discontinuation of attenuated androgens may have the potential for transient adverse effects, such as an increase in the rate of attacks or effects related to hormone withdrawal. Our survey showed that physicians often taper androgens to prevent increases in HAE attacks and possible withdrawal complications. Conclusion: Based on both experiences of the physicians who responded to our survey and reports in the endocrine literature, we provided recommendations for androgen tapering. However, we noted that the likelihood of adverse effects due to androgen withdrawal in patients with HAE is poorly understood and requires further study.

Management of hereditary angioedema in Japan: Focus on icatibant for the treatment of acute attacks

Hereditary angioedema (HAE) is characterized by unpredictable, recurring and painful swelling episodes that can be disabling or even life-threatening. Awareness of HAE has progressively grown worldwide, and options for treatment of acute attacks and prevention of future attacks continue to expand; however, unmet needs in diagnosis and treatment remain. In Japan, recognition of HAE within the medical community remains low, and numerous obstacles complicate diagnosis and access to treatment. Importance of timely treatment of HAE attacks with on-demand therapies is continually demonstrated; recommended agents per the WAO/EAACI treatment guidelines published in 2018 include C1 inhibitor (C1-INH) concentrate, ecallantide, and icatibant. In Japan, multiple factors contribute to delayed HAE treatment (potentially leading to life-threatening consequences), including difficulties in finding facilities at which C1-INH agents are readily available. Recognition of challenges faced in Japan can help promote efforts to address current needs and expand access to effective therapies. Icatibant, a potent, selective bradykinin B₂ receptor antagonist, has demonstrated inhibition of various bradykinin-induced biological effects in preclinical studies and has shown efficacy in treating attacks in various clinical settings (e.g. clinical trials, real-world studies), and HAE patient populations (e.g. with C1-INH deficiency, normal C1-INH). Icatibant was approved in Japan for the treatment of HAE attacks in September 2018; its addition to the HAE treatment armamentarium contributes to improved patient care. In Japan, disease awareness and education campaigns are warranted to further advance the management of HAE patients in light of the unmet needs and the emerging availability of modern diagnostic approaches and therapies.

Hereditary angioedema in children and adolescents - A consensus update on therapeutic strategies for German-speaking countries

BACKGROUND/METHODS

At a consensus meeting in August 2018, pediatricians and dermatologists from German-speaking countries discussed the therapeutic strategy for the treatment of pediatric patients with type I and II hereditary angioedema due to C1 inhibitor deficiency (HAE-C1-INH) for Germany, Austria, and Switzerland, taking into account the current marketing approval status. HAE-C1-INH is a rare disease that usually presents during childhood or adolescence with intermittent episodes of potentially life-threatening angioedema. Diagnosis as early as possible and an optimal management of the disease are important to avoid ineffective therapies and to properly treat swelling attacks. This article provides recommendations for developing appropriate treatment strategies in the management of HAE-C1-INH in pediatric patients in German-speaking countries. An overview of available drugs in this age-group is provided, together with their approval status, and study results obtained in adults and pediatric patients.

RESULTS/CONCLUSION

Currently, plasma-derived C1 inhibitor concentrates have the broadest approval status and are considered the best available option for on-demand treatment of HAE-C1-INH attacks and for short- and long-term prophylaxis across all pediatric age-groups in German-speaking countries. For on-demand treatment of children aged 2 years and older, recombinant C1-INH and bradykinin-receptor antagonist icatibant are alternatives. For long-term prophylaxis in adolescents, the parenteral kallikrein inhibitor lanadelumab has recently been approved and can be recommended due to proven efficacy and safety.

Long-term safety and efficacy of subcutaneous C1-inhibitor in older patients with hereditary angioedema

BACKGROUND

Patients aged 65 years and older with hereditary angioedema (HAE) owing to C1-inhibitor (C1-INH) deficiency may have an altered response to treatment and are at higher risk for treatment-related adverse events (AEs) because of comorbidities and polypharmacy.

OBJECTIVE

To investigate the safety and efficacy of subcutaneous C1 esterase inhibitor (C1-INH) in patients aged 65 years and older treated in an open-label extension of a phase 3 trial.

METHODS

Eligible patients (≥4 attacks for more than 2 consecutive months) were randomized to receive twice-weekly subcutaneous C1-INH with a dosage of 40 IU/kg or 60 IU/kg for 52 to 140 weeks. Safety end points and efficacy outcomes were evaluated for patients aged 65 years and above and younger than 65 years.

RESULTS

Of the 126 patients treated, 10 were 65 years and older (mean age [range], 68 [65-72 years]). A total of 8 of 10 patients had multiple comorbidities, and 6 of these 10 patients were taking more than 5 non-HAE-related drugs concomitantly. AEs occurring in more than 1 patient included injection site bruising (n = 2, related), injection site pain (n = 2, related), urinary tract infection (n = 2, unrelated), and diarrhea (n = 2, unrelated). No thromboembolic events or cases of anaphylaxis were reported. Two patients aged 65 years and older experienced unrelated serious AEs (dehydration and hypokalemia in 1 and pneumonia and an HAE attack leading to hospitalization in another). A total of 6 of 9 evaluable patients were responders, with a greater than or equal to 50% reduction in HAE attacks vs prestudy; 6 of 10 patients had less than 1 attack over 4 weeks and 3 were attack-free (median attack rate, 0.52 attacks per month).

CONCLUSION

Subcutaneous C1-INH was well-tolerated and effective in the management of HAE in patients aged 65 years and older with multiple comorbid conditions and polypharmacy.

Patient-reported burden of hereditary angioedema: findings from a patient survey in the United States

BACKGROUND

Hereditary angioedema (HAE) with C1-inhibitor deficiency is associated with painful, potentially fatal attacks affecting subcutaneous or submucosal tissues.

OBJECTIVE

To evaluate HAE burden from the patients' perspective.

METHODS

This was a noninterventional survey of patients with HAE in the United States, conducted from March 17 to April 28, 2017. Patients were recruited through the US Hereditary Angioedema Association. Key eligibility criteria included the following: (1) aged 18 years and older, (2) self-reported physician diagnosis of HAE type I or II, (3) 1 or more HAE attacks or prodromal symptoms within the last year, and (4) receipt of HAE medication for an attack within the last 2 years. Descriptive analyses were conducted.

RESULTS

A total of 445 patients completed the survey. Most patients (92.8%) were aged 18 to 64 years with HAE type I (78.4%) and had a positive family history (78.4%). Mean (SD) ages at symptom onset and diagnosis were 12.5 (9.1) and 20.1 (13.7) years, respectively. Most patients (78.7%) experienced an attack within the past month. The abdomen (58.0%) and extremities (46.1%) were commonly affected sites; pain (73.9%) and abdominal (57.0%) and nonabdominal (55.1%) swelling were frequently reported symptoms. Most patients (68.5%) had received or were currently receiving long-term prophylaxis. Most patients (88.8%) reported visiting allergists or immunologists, whereas 9.2% visited emergency departments or urgent care clinics. Per the Hospital Anxiety and Depression Scale, 49.9% and 24.0% of respondents had anxiety and depression, respectively. Mean Hereditary Angioedema-Quality of Life scores were generally lower with higher attack frequency. General health was "poor" or "fair" for 24.8% of patients. Mean (SD) percentage impairments were 5.9% (14.1%) for absenteeism, 23.0% (25.8%) for presenteeism, 25.4% (28.1%) for work productivity loss, and 31.8% (29.7%) for activity impairment.

CONCLUSION

Despite treatment advances, patients with HAE in the United States continue to have a high burden of illness.

Changes of coagulation parameters during erythema marginatum in patients with hereditary angioedema

BACKGROUND

Hereditary angioedema (HAE) with C1-inhibitor deficiency (C1-INH-HAE) is characterized by recurrent episodes of subcutaneous/submucosal edema, which may be preceded by erythema marginatum (EM) as a prodromal symptom. Our aim was to analyze the changes occurring in the parameters of the coagulation system during the development of EM and HAE attacks.

MATERIALS AND METHODS

Eight C1-INH-HAE patients (1 male, 7 females, median age: 41.7 years) were studied. Blood samples were obtained from all patients (during symptom-free periods, EM, and HAE attacks), as well as from 20 sex- and age-matched healthy controls. Prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen, D-dimer, Factor V, Factor VII, Factor X, Factor XI, and Factor XII levels were measured.

RESULTS

D-dimer levels were significantly lower, whereas aPTT was significantly prolonged in healthy controls vs. the values measured during the symptom-free period (p = 0.0497; p = 0.0043), in the presence of EM (p = 0.002; p = 0.0002), or during HAE attacks (p < 0.0001; p = 0.0002). We observed the following differences between samples taken during HAE attacks vs. in symptom-free periods: D-dimer levels were significantly elevated (p = 0.0391), while aPTT was significantly shorter during HAE attacks (p = 0.0159). D-dimer levels were significantly higher during EM than in symptom-free periods (p = 0.0078). Comparing the samples drawn during EM or during HAE attacks, there were no significant differences in the study parameters.

CONCLUSIONS

D-dimer levels were elevated during EM and this suggests that EM may be part of the HAE attack. Nevertheless, further research into the complement and kinin-kallikrein systems is needed in more patients for a better understanding of the pathomechanism of EM.

Management of patients with hereditary angio-oedema in dental, oral, and maxillofacial surgery: a review

Hereditary angio-oedema (HEA) is an autosomal dominant, life-threatening genetic disorder that is caused by insufficiency or dysfunction of the C1 esterase inhibitor that develops coincidentally with recurrent oedema in the skin, internal organs, and upper respiratory tract. Increased production of bradykinin secondary to increased plasma kallikrein activity is the primary cause of attacks. Dental procedures cause emotional stress and mechanical trauma and may also initiate attacks. The most feared complication is asphyxiation as a result of laryngeal oedema. Cases that resulted in death after tooth extraction have been reported, so dentists and oral and maxillofacial surgeons should take maximum care in the treatment of patients with HAO, consult with the patient's doctor, and ensure that prophylaxis is given before the procedure. They should work as atraumatically as possible and use procedures to minimise stress. In the event of an attack of HAO, despite all the correct measures having been taken, the procedure should be terminated immediately and treatment of the attack started as soon as possible. The first drugs for the treatment of acute attacks are C1-INH (C1 inhibitor), ecallantide, or icatibant.

Successful Long-Term Prophylactic Treatment With Subcutaneous C1 Esterase Inhibitor in a Patient With Hereditary Angioedema

BACKGROUND

Hereditary angioedema (HAE) patients suffer from recurrent swellings. Current standard therapy consists of C1 esterase inhibitor (C1-INH) and bradykinin receptor B2 antagonists. Severe courses require prophylactic treatment. For such patients, it has been demonstrated that the intravenous (IV) administration of C1-INH [C1-INH(IV)] is safe and effective. A new prophylactic option is subcutaneous (SC) treatment with C1-INH.

METHODS AND CASE

We present the case of an HAE patient placed on prophylactic C1-INH(IV) therapy due to frequent attacks when managed with on-demand therapy. An implanted port allowed the periodical and safe application of medication until the device was explanted due to an infection. Due to the poor venous access, repeated IV application failed. Therefore, we began a SC treatment with 1500 IU C1-INH [C1-INH(SC)] as long-term prophylaxis and analyzed the clinical course over 16 months.

RESULTS

Under the SC prophylaxis, the number of attacks were reduced to 1/month in comparison to 4.33/month with no prophylactic treatment and 1.83/month with C1-INH(IV). No severe attacks and no attack within the upper airway occurred over the 16 months of C1-INH(SC) treatment. As a result, quality of life improved, as measured by the Angioedema quality of life questionaire (AE-QoL).

CONCLUSION

Self-administered SC prophylactic use of C1-INH over a period of 16 months seems to be a well tolerated and efficient. The patient's quality of life improved, and by learning self-application, the patient gained independence.

Hereditary Angio-Oedema for Dermatologists

Among angio-oedema patients, hereditary angio-oedema (HAE) should not be overlooked. Besides skin swellings, these patients might have very painful abdominal attacks and potentially life-threatening angio-oedema of the upper airway. They will not respond to traditional anti-allergic therapy with antihistamines, corticosteroids, and adrenaline, and instead need specific drugs targeting the kallikrein-kinin pathway. Classically, patients with HAE have a quantitative or qualitative deficiency of the C1 inhibitor (C1INH) due to different mutations in SERPING1, although a new subtype with normal C1INH has been recognised more recently. This latter variant is diagnosed based on clinical features, family history, or molecular genetic testing for mutations in F12, ANGPT1,or PLG.The diagnosis of HAE is often delayed due to a general unfamiliarity with this orphan disease. However, undiagnosed patients are at an increased risk of unnecessary surgical interventions or life-threatening laryngeal swellings. Within the last decade, new and effective therapies have been developed and launched for acute and prophylactic therapy. Even more drugs are under evaluation in clinical trials. It is therefore of utmost importance that patients with HAE are diagnosed as soon as possible and offered relevant therapy with orphan drugs to reduce morbidity, prevent mortality, and improve quality of life.

Lanadelumab for the Prophylactic Treatment of Hereditary Angioedema with C1 Inhibitor Deficiency: A Review of Preclinical and Phase I Studies

Hereditary angioedema (HAE) with C1 esterase inhibitor (C1-INH) deficiency (C1-INH-HAE) is a rare disease characterized by diminished levels or dysfunctional activity of C1-INH, leading to dysregulated plasma kallikrein activity within the kallikrein-kinin pathway. Symptoms manifest as painful, potentially life-threatening swelling of subcutaneous tissues throughout the body and/or submucosal edema in the upper airway or gastrointestinal tract. Attacks recur with unpredictable frequency, intensity, and duration, placing a heavy burden on patients' daily lives. Despite improved availability of medications for on-demand treatment during attacks and prophylaxis of future attacks, unmet needs remain. Lanadelumab, a fully human monoclonal antibody, may help address some of the limitations of existing prophylactic options (e.g., the need for intravenous administration or frequent dosing). Preclinical studies demonstrate that it is highly potent and specifically inhibits plasma kallikrein, and findings from phase Ia and Ib studies suggest this agent is well tolerated and provides sustained inhibition of plasma kallikrein, allowing for less frequent dosing. The phase III HELP Study (NCT02586805) evaluating the efficacy and safety of lanadelumab in preventing HAE attacks has been completed, and its open-label extension (NCT02741596) is ongoing. Lanadelumab is now approved in the USA and Canada for prophylaxis to prevent attacks of HAE in patients aged ≥ 12 years. This review provides an overview of the discovery and clinical development of lanadelumab, from preclinical through phase Ib studies, characterizing its safety/tolerability, efficacy, and pharmacokinetic and pharmacodynamic profiles. It also highlights how this agent may positively impact clinical care of patients with C1-INH-HAE.

Fixed-Dose Subcutaneous C1-Inhibitor Liquid for Prophylactic Treatment of C1-INH-HAE: SAHARA Randomized Study

BACKGROUND

Hereditary angioedema (HAE) with C1 inhibitor deficiency (C1-INH) is characterized by swelling of subcutaneous and/or submucosal tissues.

OBJECTIVE

To evaluate efficacy/safety of fixed-dose subcutaneous plasma-derived C1-INH (pdC1-INH) liquid for HAE attack prevention (NCT02584959).

METHODS

Eligible patients were ≥12 years with ≥2 monthly attacks prescreening or pre-long-term prophylaxis. In a partial crossover design, 80% of patients were randomized to placebo or pdC1-INH liquid for 14 weeks and crossed over from active to placebo or vice versa for another 14 weeks. The remainder were randomized to pdC1-INH liquid for 28 weeks. The primary efficacy endpoint was normalized number of attacks (NNA) versus placebo. Key additional endpoints were the proportion of patients achieving NNA reduction ≥50%, attack severity, number of attack-free days, and safety.

RESULTS

Seventy-five patients were randomized and 58 (77%) completed the study. Mean age 41 years; 88% HAE type I. Least-squares means of NNA were reduced from 3.9 with placebo to 1.6 with pdC1-INH (from day 1; P < .0001). Most patients had ≥50% NNA reduction with pdC1-INH (from day 1, 78%). A total of 8.8% of placebo-treated patients were attack-free and 5.3%, 22.8%, and 63.2% had mild, moderate, and severe attacks, respectively; 37.5% of pdC1-INH-treated patients were attack-free and 8.9%, 26.8%, and 26.8% had mild, moderate, and severe attacks, respectively. Treatment-emergent adverse event rates were similar between groups (52% vs 56% for pdC1-INH crossover vs placebo, respectively).

CONCLUSIONS

Fixed-dose subcutaneous pdC1-INH liquid was superior to placebo in preventing HAE attacks and demonstrated a favorable safety profile.

Isolated angioedema: An overview of clinical features and etiology

Angioedema can occur in isolation, accompanied by urticaria, or as a feature of anaphylaxis in mast cell-mediated disorders, bradykinin-mediated disorders, as well as in others with unknown mechanisms, such as infections, rare disorders, or idiopathic angioedema. In mast cell-mediated angioedema, other signs and symptoms of mast cell-mediator release are frequently seen. However, clear evidence of mast cell degranulation may be absent in histaminergic angioedema. Bradykinin-induced angioedema is not associated with urticaria or other symptoms of type I hypersensitivity reactions. For many of the known triggers of angioedema, the mechanism is unclear. While mast cell and bradykinin-mediated angioedema are relatively well defined in terms of diagnostic and therapeutic approach, angioedema with unknown mechanisms represents a challenge for patients and clinicians alike. Elucidating the clinical pattern and the possible causes of isolated angioedema is the key to a correct diagnosis. This review summarizes the causes, and clinical features of angioedema, with a focus on isolated angioedema.

Management of patients with hereditary angioedema in Germany: comparison with other countries in the Icatibant Outcome Survey

Background

The Icatibant Outcome Survey (IOS; NCT01034969) is a Shire‐sponsored, international, observational study monitoring the safety and effectiveness of icatibant, a bradykinin B2 receptor antagonist approved for the acute treatment of adults with hereditary angioedema with C1 inhibitor deficiency (HAE‐C1‐INH).

Objective

To report IOS data comparing demographic and icatibant treatment outcomes in patients with HAE‐C1‐INH from Germany to HAE‐C1‐INH patients from 11 other IOS countries.

Methods

A descriptive, retrospective, comparative analysis of data from 685 IOS patients with HAE‐C1‐INH from seven centres in Germany (n = 93) vs. centres from Austria, Brazil, Czech Republic, Denmark, France, Greece, Israel, Italy, Spain, Sweden and the United Kingdom (n = 592, July 2009–January 2017). Icatibant treatment outcomes were retrieved from patients with complete attack outcome data for time to treatment, time to resolution and attack duration (160 attacks in 42 German patients and 1442 attacks in 251 patients from other IOS countries).

Results

German patients reported significantly fewer severe/very severe attacks (38.7% vs. 57.5%, respectively; P < 0.001). The proportion of attacks treated with a single icatibant injection was significantly higher in German patients (97.1% vs. 91.6%, P = 0.0003). The median time to treatment (0.0 h vs. 1.5 h), time to resolution (3.0 h vs. 7.0 h) and attack duration (4.3 h vs. 10.5 h) in German patients vs. other IOS countries were all significantly shorter (all P < 0.0001). No meaningful differences were identified between patients from Germany and other countries with regard to sex, median age at enrolment, median age at symptom onset and median age at diagnosis.

Conclusion

German IOS patients share similar demographic characteristics to patients from other IOS countries yet treat their attacks with icatibant significantly earlier and have markedly fewer severe or very severe attacks. Factors including regional access to and availability of icatibant may drive these outcomes and warrant further investigation.

The international WAO/EAACI guideline for the management of hereditary angioedema-The 2017 revision and update

Hereditary Angioedema (HAE) is a rare and disabling disease. Early diagnosis and appropriate therapy are essential. This update and revision of the global guideline for HAE provides up-to-date consensus recommendations for the management of HAE. In the development of this update and revision of the guideline, an international expert panel reviewed the existing evidence and developed 20 recommendations that were discussed, finalized and consented during the guideline consensus conference in June 2016 in Vienna. The final version of this update and revision of the guideline incorporates the contributions of a board of expert reviewers and the endorsing societies. The goal of this guideline update and revision is to provide clinicians and their patients with guidance that will assist them in making rational decisions in the management of HAE with deficient C1-inhibitor (type 1) and HAE with dysfunctional C1-inhibitor (type 2). The key clinical questions covered by these recommendations are: (1) How should HAE-1/2 be defined and classified?, (2) How should HAE-1/2 be diagnosed?, (3) Should HAE-1/2 patients receive prophylactic and/or on-demand treatment and what treatment options should be used?, (4) Should HAE-1/2 management be different for special HAE-1/2 patient groups such as pregnant/lactating women or children?, and (5) Should HAE-1/2 management incorporate self-administration of therapies and patient support measures?

Emotional processes and stress in children affected by hereditary angioedema with C1-inhibitor deficiency: a multicenter, prospective study

Background

Hereditary angioedema with C1-inhibitor deficiency (C1-INH-HAE) is characterized by recurrent edema of unpredictable frequency and severity. Stress, anxiety, and low mood are among the triggering factors most frequently reported. Impaired regulation and processing of emotions, also known as alexithymia, may influence outcomes. The aim of this study was to confirm the presence of alexithymia and stress in children with C1-INH-HAE, to determine whether they are also present in children affected by other chronic diseases, and to investigate their relationship with C1-INH-HAE severity. Data from children with C1-INH-HAE (n = 28) from four reference centers in Italy were compared with data from children with type 1 diabetes (T1D; n = 23) and rheumatoid arthritis (RA; n = 25). Alexithymia was assessed using the Alexithymia Questionnaire for Children scale; perceived stress was assessed using the Coddington Life Event Scale for Children (CLES-C).

Results

Mean age (standard deviation [SD]) in the C1-INH-HAE, T1D, and RA groups was 11.8 (3.3), 11.7 (2.9), and 11.1 (2.6) years, respectively. Mean C1-INH-HAE severity score was 5.9 (2.1), indicating moderate disease. Alexithymia scores were similar among disease groups and suggestive of difficulties in identifying and describing emotions; CLES-C scores tended to be worse in C1-INH-HAE children. C1-INH-HAE severity was found to correlate significantly and positively with alexithymia (p = 0.046), but not with perceived stress. Alexithymia correlated positively with perceived stress.

Conclusions

Alexithymia is common in children with chronic diseases. In C1-INH-HAE, it may result in increased perceived stress and act as a trigger of edema attacks. Comprehensive management of C1-INH-HAE children should consider psychological factors.

Electronic supplementary material

The online version of this article (10.1186/s13023-018-0871-x) contains supplementary material, which is available to authorized users.