Hereditary angioedema: New therapeutic options for a potentially deadly disorder

Although the biochemistry of hereditary angioedema (HAE) is fairly well understood today, the lag in diagnosis of a decade or more suggests that clinicians have low awareness of this disease. This lag in diagnosis and hence treatment certainly stems from the rarity and complexity of the presentation which can be easily mistaken for allergic and non-allergic reactions alike. The symptoms of the disease include acute swelling of any or multiple parts of the body. The attacks may be frequent or rare, and they may vary substantially in severity, causing stomach discomfort or periorbital swelling in mild cases and hypovolemic shock due to abdominal fluid shift or asphyxiation in the most severe cases. Given that these patients are at significant risk for poor quality of life and death, greater awareness of this disease is needed to ensure that newly available, effective medications are used in these patients. These new medications represent significant advances in HAE therapy because they are targeted at the plasma cascades implicated in the pathophysiology of this disease. The clinical presentation of HAE, overlapping symptoms with other angioedemas, and available therapies are reviewed

The establishment and utility of Sweha-Reg: a Swedish population-based registry to understand hereditary angioedema

<p>Abstract</p> <p>Background</p> <p>The importance of acquiring comprehensive epidemiological and clinical data on hereditary angioedema has increasingly caught the attention of physicians and scientists around the world. The development of networks and creation of comprehensive policies to improve care of people suffering from rare diseases, such as hereditary angioedema, is a stated top priority of the European Union.</p> <p>Hereditary angioedema is a rare disease, that it may be life-threatening. Although the exact prevalence is unknown, current estimates suggest that it is 1/10,000–1/150,000 individuals. The low prevalence requires combined efforts to gain accurate epidemiological data on the disease and so give us tools to reduce morbidity and mortality, and improve quality of life of sufferers.</p> <p>Methods</p> <p>Sweha-Reg is a population-based registry of hereditary angioedema in Sweden with the objectives of providing epidemiological data, and so creates a framework for the study of this disease. The registry contains individual-based data on diagnoses, treatments and outcomes.</p> <p>Conclusion</p> <p>The present manuscript seeks to raise awareness of the existence of Sweha-Reg to stimulate the international collaboration of registries. A synthesis of data from similar registries across several countries is required to approach an inclusive course understanding of HAE.</p

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

Abstract 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? This article is co-published with permission in Allergy and the World Allergy Organization Journal

Consensus on treatment goals in hereditary angioedema : a global Delphi initiative

Background: Hereditary angioedema (HAE) is a rare, life-threatening genetic disorder characterized by recurrent episodes of subcutaneous or submucosal angioedema. The ultimate goals of treatment for HAE remain ill-defined. Objectives: The aim of this Delphi process was to define the goals of HAE treatment and to examine which factors should be considered when assessing disease control and normalization of the patient's life. Methods: The Delphi panel comprised 23 participants who were selected based on involvement with scientific research on HAE or coauthorship of the most recent update and revision of the World Allergy Organization/European Academy of Allergy and Clinical Immunology guideline on HAE. The process comprised 3 rounds of voting. The final round aimed to aggregate the opinions of the expert panel and to achieve consensus. Results: Two direct consensus questions were posed in round 2, based on the responses received in round 1, and the panel agreed that the goals of treatment are to achieve total control of the disease and to normalize the patient's life. For the third round of voting, 21 statements were considered, with the participants reaching consensus on 18. It is clear from the wide-ranging consensus statements that the burdens of disease and treatment should be considered when assessing disease control and normalization of patients’ lives. Conclusions: The ultimate goal for HAE treatment is to achieve no angioedema attacks. The availability of improved treatments and disease management over the last decade now makes complete control of HAE a realistic possibility for most patients

Long-Term Outcomes with Subcutaneous C1-Inhibitor Replacement Therapy for Prevention of Hereditary Angioedema Attacks

Background: For the prevention of attacks of hereditary angioedema (HAE), the efficacy and safety of subcutaneous human C1-esterase inhibitor (C1-INH[SC]; HAEGARDA, CSL Behring) was established in the 16-week Clinical Study for Optimal Management of Preventing Angioedema with Low-Volume Subcutaneous C1-Inhibitor Replacement Therapy (COMPACT). Objective: To assess the long-term safety, occurrence of angioedema attacks, and use of rescue medication with C1-INH(SC). Methods: Open-label, randomized, parallel-arm extension of COMPACT across 11 countries. Patients with frequent angioedema attacks, either study treatment-naive or who had completed COMPACT, were randomly assigned (1:1) to 40 IU/kg or 60 IU/kg C1-INH(SC) twice per week, with conditional uptitration to optimize prophylaxis (ClinicalTrials.gov registration no. NCT02316353). Results: A total of 126 patients with a monthly attack rate of 4.3 in 3 months before entry in COMPACT were enrolled and treated for a mean of 1.5 years; 44 patients (34.9%) had more than 2 years of exposure. Mean steady-state C1-INH functional activity increased to 66.6% with 60 IU/kg. Incidence of adverse events was low and similar in both dose groups (11.3 and 8.5 events per patient-year for 40 IU/kg and 60 IU/kg, respectively). For 40 IU/kg and 60 IU/kg, median annualized attack rates were 1.3 and 1.0, respectively, and median rescue medication use was 0.2 and 0.0 times per year, respectively. Of 23 patients receiving 60 IU/kg for more than 2 years, 19 (83%) were attack-free during months 25 to 30 of treatment. Conclusions: In patients with frequent HAE attacks, long-term replacement therapy with C1-INH(SC) is safe and exhibits a substantial and sustained prophylactic effect, with the vast majority of patients becoming free from debilitating disease symptoms

Effect of Lanadelumab Compared with Placebo on Prevention of Hereditary Angioedema Attacks : a Randomized Clinical Trial

Importance: Current treatments for long-term prophylaxis in hereditary angioedema have limitations. Objective: To assess the efficacy of lanadelumab, a fully human monoclonal antibody that selectively inhibits active plasma kallikrein, in preventing hereditary angioedema attacks. Design, Setting, and Participants: Phase 3, randomized, double-blind, parallel-group, placebo-controlled trial conducted at 41 sites in Canada, Europe, Jordan, and the United States. Patients were randomized between March 3, 2016, and September 9, 2016; last day of follow-up was April 13, 2017. Randomization was 2:1 lanadelumab to placebo; patients assigned to lanadelumab were further randomized 1:1:1 to 1 of the 3 dose regimens. Patients 12 years or older with hereditary angioedema type I or II underwent a 4-week run-in period and those with 1 or more hereditary angioedema attacks during run-in were randomized. Interventions: Twenty-six-week treatment with subcutaneous lanadelumab 150 mg every 4 weeks (n = 28), 300 mg every 4 weeks (n = 29), 300 mg every 2 weeks (n = 27), or placebo (n = 41). All patients received injections every 2 weeks, with those in the every-4-week group receiving placebo in between active treatments. Main Outcome and Measures: Primary efficacy end point was the number of investigator-confirmed attacks of hereditary angioedema over the treatment period. Results: Among 125 patients randomized (mean age, 40.7 years [SD, 14.7 years]; 88 females [70.4%]; 113 white [90.4%]), 113 (90.4%) completed the study. During the run-in period, the mean number of hereditary angioedema attacks per month in the placebo group was 4.0; for the lanadelumab groups, 3.2 for the every-4-week 150-mg group; 3.7 for the every-4-week 300-mg group; and 3.5 for the every-2-week 300-mg group. During the treatment period, the mean number of attacks per month for the placebo group was 1.97; for the lanadelumab groups, 0.48 for the every-4-week 150-mg group; 0.53 for the every-4-week 300-mg group; and 0.26 for the every-2-week 300-mg group. Compared with placebo, the mean differences in the attack rate per month were -1.49 (95% CI, -1.90 to -1.08; P &lt;.001); -1.44 (95% CI, -1.84 to -1.04; P &lt;.001); and -1.71 (95% CI, -2.09 to -1.33; P &lt;.001). The most commonly occurring adverse events with greater frequency in the lanadelumab treatment groups were injection site reactions (34.1% placebo, 52.4% lanadelumab) and dizziness (0% placebo, 6.0% lanadelumab). Conclusions and Relevance: Among patients with hereditary angioedema type I or II, treatment with subcutaneous lanadelumab for 26 weeks significantly reduced the attack rate compared with placebo. These findings support the use of lanadelumab as a prophylactic therapy for hereditary angioedema. Further research is needed to determine long-term safety and efficacy. Trial Registration: EudraCT Identifier: 2015-003943-20; ClinicalTrials.gov Identifier: NCT02586805

Long-Term Outcomes with Subcutaneous C1-Inhibitor Replacement Therapy for Prevention of Hereditary Angioedema Attacks

Background For the prevention of attacks of hereditary angioedema (HAE), the efficacy and safety of subcutaneous human C1-esterase inhibitor (C1-INH[SC]; HAEGARDA, CSL Behring) was established in the 16-week Clinical Study for Optimal Management of Preventing Angioedema with Low-Volume Subcutaneous C1-Inhibitor Replacement Therapy (COMPACT). Objective To assess the long-term safety, occurrence of angioedema attacks, and use of rescue medication with C1-INH(SC). Methods Open-label, randomized, parallel-arm extension of COMPACT across 11 countries. Patients with frequent angioedema attacks, either study treatment-naive or who had completed COMPACT, were randomly assigned (1:1) to 40 IU/kg or 60 IU/kg C1-INH(SC) twice per week, with conditional uptitration to optimize prophylaxis (ClinicalTrials.gov registration no. NCT02316353). Results A total of 126 patients with a monthly attack rate of 4.3 in 3 months before entry in COMPACT were enrolled and treated for a mean of 1.5 years; 44 patients (34.9%) had more than 2 years of exposure. Mean steady-state C1-INH functional activity increased to 66.6% with 60 IU/kg. Incidence of adverse events was low and similar in both dose groups (11.3 and 8.5 events per patient-year for 40 IU/kg and 60 IU/kg, respectively). For 40 IU/kg and 60 IU/kg, median annualized attack rates were 1.3 and 1.0, respectively, and median rescue medication use was 0.2 and 0.0 times per year, respectively. Of 23 patients receiving 60 IU/kg for more than 2 years, 19 (83%) were attack-free during months 25 to 30 of treatment. Conclusions In patients with frequent HAE attacks, long-term replacement therapy with C1-INH(SC) is safe and exhibits a substantial and sustained prophylactic effect, with the vast majority of patients becoming free from debilitating disease symptoms