Hereditary angioedema: increased number of attacks after frequent treatments with C1 inhibitor concentrate

[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 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.

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.

Successful treatment with Cinryze® replacement therapy of a pregnant patient with hereditary angioedema: a case report

Background

Hereditary angioedema (HAE) is a rare disease characterized with recurrent swelling of subcutaneous or mucosal tissue that resolves in approximately 3 days. It can be presented with peripheral edema, abdominal and life-threatening laryngeal angioedema. A variety of triggers are known to cause episodes of angioedema including estrogen exposure. There are different reports regarding the effect of pregnancy on HAE attacks, and in some patients, the pregnancy is a recognized triggering factor.

Case presentation

We present a female Caucasian patient with pre-existing HAE and disease exacerbations during pregnancy, requiring prophylactic use of plasma-derived C1 inhibitor concentrate. She was treated with Cinryze® replacement therapy throughout the pregnancy 1000 IU i.v. 48 times. She gave birth to a healthy male infant, via C-section. After the delivery, the patient was symptom-free for 6 months and required no treatment for HAE.

Conclusions

In the case presented, the angioedema attacks worsened as the pregnancy progressed. The treatment with Cinryze® replacement therapy was effective and safe during pregnancy, with no adverse effects on the infant.

Acquired and hereditary forms of recurrent angioedema: Update of treatment

The aim of treatment of hereditary angioedema (HAE) due to C1 esterase inhibitor deficiency (HAE-C1-INH) is either treating acute attacks or preventing attacks by using prophylactic treatment. For treating acute attacks, plasma-derived C1 inhibitor (C1-INH) concentrates, a bradykinin B2 receptor antagonist, and a recombinant human C1-INH are available in Europe. In the United States, a plasma-derived C1-INH concentrate, a bradykinin B2 receptor antagonist, and a plasma kallikrein inhibitor were approved for the treatment of acute attacks. Fresh frozen plasma is also available for treating acute attacks. Short-term prophylactic treatment focuses on C1-INH and attenuated androgens. Long-term prophylactic treatments include attenuated androgens such as danazol, stanozolol, and oxandrolone, antifibrinolytics, and a plasma-derived C1-INH concentrate. Plasma-derived C1-INH and a bradykinin B2 receptor antagonist are admitted for self-administration and home therapy. So the number of management options increased considerably within the last few years thus helping to diminish the burden of HAE.

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?

Optimum Use of Acute Treatments for Hereditary Angioedema: Evidence-Based Expert Consensus

Acute treatment of hereditary angioedema due to C1 inhibitor deficiency has become available in the last 10 years and has greatly improved patients’ quality of life. Two plasma-derived C1 inhibitors (Berinert and Cinryze), a recombinant C1 inhibitor (Ruconest/Conestat alpha), a kallikrein inhibitor (Ecallantide), and a bradykinin B2 receptor inhibitor (Icatibant) are all effective. Durably good response is maintained over repeated treatments and several years. All currently available prophylactic agents are associated with breakthrough attacks, therefore an acute treatment plan is essential for every patient. Experience has shown that higher doses of C1 inhibitor than previously recommended may be desirable, although only recombinant C1 inhibitor has been subject to full dose–response evaluation. Treatment of early symptoms of an attack, with any licensed therapy, results in milder symptoms, more rapid resolution and shorter duration of attack, compared with later treatment. All therapies have been shown to be well-tolerated, with low risk of serious adverse events. Plasma-derived C1 inhibitors have a reassuring safety record regarding lack of transmission of virus or other infection. Thrombosis has been reported in association with plasma-derived C1 inhibitor in some case series. Ruconest was associated with anaphylaxis in a single rabbit-allergic volunteer, but no further anaphylaxis has been reported in those not allergic to rabbits despite, in a few cases, prior IgE sensitization to rabbit or milk protein. Icatibant is associated with high incidence of local reactions but not with systemic effects. Ecallantide may cause anaphylactoid reactions and is given under supervision. For children and pregnant women, plasma-derived C1 inhibitor has the best evidence of safety and currently remains first-line treatment.

Nanofiltrated C1-esterase-inhibitor in the prophylactic treatment of bradykinin-mediated angioedema

BACKGROUND

Patients suffering from bradykinin-induced angioedema show recurrent swelling of subcutaneous and submucosal structures. Increased bradykinin levels lead to an increase in vascular permeability and edema formation. Current therapy consists of B2 bradykinin receptor antagonists, C1-esterase-inhibitor (C1-INH) concentrate, or the kallikrein inhibitor ecallantide. In most cases the treatment of acute attacks is sufficient. Prophylactic therapy is recommended only in severe cases. C1-INHc has been shown a safe and efficient option. Its effect on the quality of life has not yet been analyzed.

STUDY DESIGN AND METHODS

Patients with inadequate disease control despite an "on-demand therapy" including C1-INHc and/or the B2 receptor antagonist icatibant were switched to long-term prophylaxis consisting in an individual dose of intravenous C1-INHc (Cinryze). None of the patients had been previously treated with ecallantide. Disease-specific quality-of-life questionnaires and patient records were used for evaluation. Disease control, quality of life, adverse events, and administered dosage per month were compared for 6 months on on-demand therapy and the following 6 months under prophylactic therapy.

RESULTS

Data of seven patients with hereditary angioedema (HAE) and one patient with acquired angioedema were evaluated. Prophylactic therapy with Cinryze led to a significant and clinically relevant reduction in the overall attack frequency from 6.7 to 2.3 per month without relevant side effects. The frequency of severe attacks was reduced by 89% and quality of life significantly improved.

CONCLUSION

Prophylaxis with Cinryze led to a significantly improved quality of life in our cohort of patients with high-frequency bradykinin-induced angioedema attacks that were not sufficiently treated with on-demand medication.

Stability of murine bradykinin type 2 receptor despite treatment with NO, bradykinin, icatibant, or C1-INH

BACKGROUND

Little is known about factors which trigger and/or contribute to hereditary angioedema or ACE-inhibitor-mediated angioedema including variations in bradykinin type 2 receptor (B2R) expression and activity.

METHODS

Protein and mRNA expression of B2R and the increase of intracellular calcium (iCa) in response to bradykinin were monitored in porcine and murine endothelial cells in response to NO donors or bradykinin. B2R protein expression was evaluated in skin, heart, and lung of (i) mice with endothelial-specific overexpression of eNOS (eNOS(tg) ), (ii) in eNOS(-/-) mice and (iii) in C57BL/6 mice treated with the NO donor pentaerythritol tetranitrate (PETN), the NOS inhibitor l-nitroarginine (L-NA), plasma pool C1-INH, and the B2R antagonist icatibant. Aortic reactivity to bradykinin was investigated including eNOS(-/-) mice.

RESULTS

B2R protein and mRNA expression remained unchanged in cells subjected to L-NA, NO donors, and bradykinin in a time- and concentration-dependent manner. Likewise, increases of iCa in murine brain endothelial cells remained unchanged. B2R protein levels were similar in eNOS(tg) and eNOS(-/-) as compared to transgene-negative littermates. Likewise, treatment of C57BL/6 mice with PETN, L-NA, C1-INH or icatibant did not change B2R protein expression. In aortic rings of C57BL/6 mice, bradykinin induced B2R-dependent constrictions which were attenuated by endothelial NO and abolished by diclofenac indicating the functional importance of B2R-induced activation of endothelial NO synthase and cyclooxygenase.

CONCLUSION

These data suggest that alterations of B2R protein expression induced by NO, bradykinin, C1-INH, or icatibant unlikely contribute to bradykinin-induced angioedema. This finding does not rule out a role for NO in bradykinin-induced extravasation and/or angioedema.

An evidence based therapeutic approach to hereditary and acquired angioedema

PURPOSE OF REVIEW

Hereditary angioedema (HAE) due to C1 esterase inhibitor (C1-INH) deficiency (HAE-C1-INH), HAE with normal C1-INH, and acquired angioedema due to C1-INH deficiency are rare but important diseases that can be associated with significant morbidity and mortality. Research into the pathogenesis of angioedema has expanded greatly and has led to new clinical trials with novel therapeutic agents and strategies.

RECENT FINDINGS

Strategies for managing HAE-C1-INH are aimed at treating acute attacks or preventing attacks through the use of prophylactic treatment. Agents available in Europe for treating acute attacks include plasma-derived C1-INH concentrates, a bradykinin B2 receptor (B2R) antagonist, and a recombinant human C1-INH. In the USA, a plasma-derived C1-INH concentrate, a bradykinin B2R antagonist, and a plasma kallikrein inhibitor have been approved for the treatment of acute HAE-C1-INH attacks. C1-INH concentrates and attenuated androgens are used for short-term prophylactic treatment. Long-term prophylactic treatments include attenuated androgens, a plasma-derived C1-INH concentrate, and antifibrinolytics. Plasma-derived C1-INH and a bradykinin B2R antagonist are approved for self-administration at home.

SUMMARY

The number of management options for HAE-C1-INH and similar conditions has increased considerably within the last few years, thus helping to alleviate the burden of these rare diseases.

Improving patient outcomes in hereditary angioedema: reducing attack frequency using routine prevention with C1 inhibitor concentrate

Hereditary angioedema (HAE) is a rare inherited disorder, characterised by recurrent oedema attacks in various regions of the body. In HAE, mutations in the C1 esterase inhibitor (C1-INH) gene result in decreased C1-INH concentrations (type I HAE) or functionally deficient C1-INH (type II HAE), leading to inappropriate activation of the kallikrein-kinin system and release of vasoactive mediators. Treatment of HAE aims to manage acute attacks (using replacement C1-INH or bradykinin B2 receptor antagonist) or prevent attacks through prophylaxis (using C1-INH or attenuated androgens). We present a case of a 67-year-old man with HAE who suffered a high number of breakthrough HAE attacks while undergoing long-term prophylaxis with attenuated androgens. Androgen therapy was safely discontinued and routine prevention therapy with C1-INH (1000 U) introduced as part of an individualised management approach, in line with published clinical trial data, which improved patient outcomes in terms of HAE attack frequency and severity.

WAO Guideline for the Management of Hereditary Angioedema

Hereditary Angioedema (HAE) is a rare disease and for this reason proper diagnosis and appropriate therapy are often unknown or not available for physicians and other health care providers. For this reason we convened a group of specialists that focus upon HAE from around the world to develop not only a consensus on diagnosis and management of HAE, but to also provide evidence based grades, strength of evidence and classification for the consensus. Since both consensus and evidence grading were adhered to the document meets criteria as a guideline. The outcome of the guideline is to improve diagnosis and management of patients with HAE throughout the world and to help initiate uniform care and availability of therapies to all with the diagnosis no matter where the residence of the individual with HAE exists.

Switch to icatibant in a patient affected by hereditary angioedema with high disease activity: a case report

Icatibant, an antagonist of the bradykinin B2 receptor, was approved for the treatment of acute attacks of hereditary angioedema in the EU in 2008. This paper presents the case of a 65-year-old woman affected by frequent acute attacks of hereditary angioedema who benefitted from a change of therapy to icatibant, following years of treatment with C1-inhibitor.

Hereditary angioedema (HAE) in children and adolescents--a consensus on therapeutic strategies

Hereditary angioedema due to C1 inhibitor (C1 esterase inhibitor) deficiency (types I and II 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 is important to avoid ineffective therapies and to properly treat swelling attacks. At a consensus meeting in June 2011, pediatricians and dermatologists from Germany, Austria, and Switzerland reviewed the currently available literature, including published international consensus recommendations for HAE therapy across all age groups. Published recommendations cannot be unconditionally adopted for pediatric patients in German-speaking countries given the current approval status of HAE drugs. This article provides an overview and discusses drugs available for HAE therapy, their approval status, and study results obtained in adult and pediatric patients. Recommendations for developing appropriate treatment strategies in the management of HAE in pediatric patients in German-speaking countries are provided.Conclusion Currently, plasma-derived C1 inhibitor concentrate is considered the best available option for the treatment of acute HAE-C1-INH attacks in pediatric patients in German-speaking countries, as well as for short-term and long-term prophylaxis.

C1 Esterase Inhibitor (Human) for the Treatment of Acute Hereditary Angioedema

Hereditary angioedema (HAE) is a relatively rare disease characterized by acute episodes of swelling. These swellings can be disfiguring, painful and life-threatening. Since the symptoms occur in different areas and most patients experience a delay in their diagnosis, resulting in unnecessary suffering and dangerous situations. HAE can have a tremendous impact on the quality of life. The major genetic deficiency in this disorder is either an absent or nonfunctional C1INH which regulates the complement, fibrinolitic, kalikrein and plasmin pathways.

A case of hereditary angioedema involving recurrent abdominal attacks

A 44-year-old Japanese woman was diagnosed with type 1 hereditary angioedema (HAE) at the age of 30. In March 2007, she began suffering from severe abdominal pain due to intestinal edema. After treatment with C1-INH concentrate, her symptoms disappeared. However, during the subsequent three years, the frequency of the attacks increased continuously, and C1-INH concentrate was necessary for treatment of every attack. The increase in the number of attacks might have been due to the frequent injection of C1-INH concentrate or the deterioration of her disease course. In a genetic investigation, the patient was found to have a novel mutation in the C1-INH gene.

Human C1-esterase inhibitor concentrate (Berinert)

Human C1-esterase inhibitor concentrate (C1-INH concentrate) is derived from human plasma and is indicated for the treatment of acute episodes of hereditary angioedema. Intravenous C1-INH concentrate provided rapid symptom relief in patients with acute abdominal or facial episodes associated with type I or II hereditary angioedema, according to the results of the randomized, double-blind, multicenter, placebo-controlled IMPACT-1 trial. The median time to the onset of symptom relief was significantly shorter with C1-INH concentrate 20 U/kg than with placebo (0.5 vs 1.5 hours). A subsequent noncomparative extension trial (IMPACT-2) showed the ongoing efficacy of 'on-demand' treatment with C1-INH concentrate; overall, the onset of symptom relief occurred in a median 30 minutes. Several additional studies demonstrated the efficacy of intravenous C1-INH concentrate in patients with laryngeal edema, skin swellings, or abdominal episodes associated with type I or II hereditary angioedema. Self-administered home therapy with intravenous C1-INH concentrate significantly improved health-related quality of life in patients with hereditary angioedema. Dermatology Life Quality Index and Short Form 36-item Health Survey scores were significantly improved from baseline by self-administered home therapy with C1-INH concentrate. Intravenous C1-INH concentrate was well tolerated in patients with hereditary angioedema, with no confirmed cases of viral transmission.

Hereditary angioedema: an update on available therapeutic options

There is no cure for hereditary angioedema (HAE). Therapeutic approaches consist of symptomatic therapy for acute attacks, short-term prophylaxis before surgery, and long-term prophylaxis for those with frequent and severe attacks. In Germany, C1-INH concentrate and icatibant are licensed for acute therapy. C1-INH concentrate, which is obtained from human plasma, is administered intravenously to restore the deficient C1-INH activity. This therapy, which has been available for decades, is effective and well-tolerated. Batch documentation is required by German law. The synthetic decapeptide icatibant is administered subcutaneously. It competes with bradykinin, the responsible inducer of edema formation, for binding to the bradykinin B2 receptor. Icatibant is also effective and well-tolerated, even on repeated administration. An additional human C1-inhibitor, a recombinant human C1-inhibitor and the recombinant inhibitor of kallikrein ecallantide are currently under development. There are no licensed treatment options available in Germany for long- and short-term prophylaxis. Androgen derivatives are established in long-term prophylaxis. However, they are associated with many adverse effects, some of which are severe. Many drug interactions also limit their use. They are contraindicated in pregnancy, lactation, for children and in cases of prostate cancer. Antifibrinolytics have fewer adverse effects but are also less effective than androgens. They are contraindicated in thromboembolic disease and impaired vision. If androgen therapy has too negative an effect on quality of life, it may be worth reducing the dose or discontinuing therapy entirely and treating attacks with acute therapy.