The Icatibant Outcome Survey: experience of hereditary angioedema management from six European countries

Oral Sebetralstat for On-Demand Treatment of Hereditary Angioedema Attacks

BACKGROUND

Approved on-demand treatments for hereditary angioedema attacks need to be administered parenterally, a route of administration that is associated with delays in treatment or withholding of therapy.

METHODS

In this phase 3, double-blind, three-way crossover trial, we randomly assigned participants at least 12 years of age with type 1 or type 2 hereditary angioedema to take up to two oral doses of sebetralstat (300 mg or 600 mg) or placebo for an angioedema attack. The primary end point, assessed in a time-to-event analysis, was the beginning of symptom relief, defined as a rating of "a little better" on the Patient Global Impression of Change scale (ratings range from "much worse" to "much better") at two or more consecutive time points within 12 hours after the first administration of the trial agent. Key secondary end points, assessed in a time-to-event analysis, were a reduction in attack severity (an improved rating on the Patient Global Impression of Severity [PGI-S] scale, with ratings ranging from "none" to "very severe") at two or more consecutive time points within 12 hours and complete attack resolution (a rating of "none" on the PGI-S scale) within 24 hours.

RESULTS

A total of 136 participants were assigned to one of six trial sequences, with 110 treating 264 attacks. The time to the beginning of symptom relief with the 300-mg dose and the 600-mg dose was faster than with placebo (P<0.001 and P = 0.001 for the two comparisons, respectively), with median times of 1.61 hours (interquartile range, 0.78 to 7.04), 1.79 hours (1.02 to 3.79), and 6.72 hours (1.34 to >12), respectively. The time to reduction in the attack severity with the 300-mg dose and the 600-mg dose was faster than with placebo (P = 0.004 and P = 0.003), with median times of 9.27 hours (interquartile range, 1.53 to >12), 7.75 hours (2.19 to >12), and more than 12 hours (6.23 to >12). The time to complete resolution was faster with the 300-mg and 600-mg doses than with placebo (P = 0.002 and P<0.001). The percentage of attacks with complete resolution within 24 hours was 42.5% with the 300-mg dose, 49.5% with the 600-mg dose, and 27.4% with placebo. Sebetralstat and placebo had similar safety profiles; no serious adverse events related to the trial agents were reported.

CONCLUSIONS

Oral sebetralstat provided faster times to the beginning of symptom relief, reduction in attack severity, and complete attack resolution than placebo. (Funded by KalVista Pharmaceuticals; KONFIDENT ClinicalTrials.gov number, NCT05259917; EudraCT number, 2021-001226-21.).

Efficacy and Safety of Rituximab-Based Treatments in Angioedema With Acquired C1-Inhibitor Deficiency

BACKGROUND

Angioedema (AE) due to acquired C1-inhibitor (C1-INH) deficiency (AAE-C1-INH) is related to excessive consumption of C1-INH or to anti-C1-INH antibodies, and is frequently associated with lymphoproliferative syndromes or monoclonal gammopathies. Standard of care for prophylactic treatment in this condition is not established. Rituximab may be effective to prevent attacks, especially if the lymphoid hemopathy is controlled, but data are scarce.

OBJECTIVE

To evaluate efficacy of rituximab in AAE-C1-INH.

METHODS

A retrospective multicenter study was carried out in France, including patients with AAE-C1-INH treated with rituximab between April 2005 and July 2019.

RESULTS

Fifty-five patients with AAE-C1-INH were included in the study, and 23 of them had an anti-C1-INH antibody. A lymphoid malignancy was identified in 39 patients, and a monoclonal gammopathy in 9. There was no associated condition in 7 cases. Thirty patients received rituximab alone or in association with chemotherapy (n = 25). Among 51 patients with available follow-up, 34 patients were in clinical remission and 17 patients had active AE after a median follow-up of 3.9 years (interquartile range, 1.5-7.7). Three patients died. The presence of anti-C1-INH antibodies was associated with a lower probability of AE remission (hazard ratio, 0.29 [95% CI, 0.12-0.67]; P = .004). Relapse was less frequent in patients with lymphoma (risk ratio, 0.27 [95% CI, 0.09-0.80]; P = .019) and in patients treated with rituximab and chemotherapy (risk ratio, 0.31 [95% CI, 0.12-0.79]; P = .014).

CONCLUSIONS

Rituximab is an efficient and well-tolerated therapeutic option in AE, especially in lymphoid malignancies and in the absence of detectable anti-C1-INH antibodies.

Current challenges and future opportunities in patient-focused management of hereditary angioedema: A narrative review

Patients with hereditary angioedema (HAE) experience a high burden of disease due to unpredictable, painful, disfiguring, and potentially life-threatening HAE attacks. Multiple HAE-specific medications for the on-demand treatment, short-term and long-term prophylaxis of HAE attacks have entered the market in recent years; however, the availability and access to these medications may vary between different countries. For this review, PubMed and EMBASE databases were searched for guidelines, consensus statements, and other publications on HAE management as well as publications on quality of life in patients with HAE. The current guidelines and recent literature on HAE management in specific countries are summarized with the aim to highlight the similarities and differences between guideline recommendations and the country-specific clinical practice. Improvement in quality of life, which is a key goal in HAE management, is also discussed and the country-specific trends are highlighted. Finally, the ways to achieve a more patient-centric approach to HAE management within the framework set by the clinical management guidelines are examined.

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.

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.

Identification of novel biomarkers to distinguish bradykinin-mediated angioedema from mast cell-/histamine-mediated angioedema

BACKGROUND

The pathophysiology of the underlying paroxysmal permeability disturbances in angioedema (AE) is not well understood.

METHODS

To identify clinical and laboratory parameters specific for a certain AE subtype, 40 AE patients were prospectively enrolled: 15 hereditary (HAE), 13 ACE-inhibitor induced (ACE-AE), and 12 mast cell-mediated without wheals in chronic spontaneous urticaria (CSU-AE). Ten healthy subjects served as controls. Serum levels of markers indicating activation of the ficolin-lectin pathway, of endothelial cells, or those indicating impairment of vascular integrity or inflammation were assessed by enzyme-linked immunosorbent assay.

RESULTS

New routine clinical diagnostic criteria could not be identified, not even for distinguishing bradykinin-mediated (BK-) AE (ie, HAE and ACE-AE) from mast cell-/histamine-mediated CSU-AE. However, FAP-α and tPA were significantly increased in all AE compared to controls. In HAE, FAP- α, tPA, uPAR, pentraxin-3, Tie-2, sE-selectin, and VE-cadherin were significantly increased compared to controls. In HAE compared to CSU-AE and ACE-AE, sE-Selectin, Tie-2, and VE-Cadherin were significantly increased, whereas for Ang-2 the difference was significant compared to CSU-AE only. Tie-2 correlated strongly negatively with C4, C1-INH activity, and C1-INH function.

CONCLUSIONS

This study is the first to compare HAE, ACE-AE, and CSU-AE. Although significance is limited by small sample size, Tie-2 was identified as a new promising biomarker candidate for HAE. FAP- α and tPA might serve as a marker for AE in general, whereas sE-selectin and Ang-2 were increased in BK-AE only. Our results add information to the role of endothelial dysfunction and serine proteases in different AE subtypes.

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.

Clinical Characteristics and Management of Angioedema Attacks in Polish Adult Patients with Hereditary Angioedema Due to C1-Inhibitor Deficiency

Hereditary angioedema (HAE) due to C1-inhibitor (C1-INH) deficiency is a rare disease characterized by recurrent swellings. This study aims to determine (i) the clinical characteristics of the HAE patient population from Poland, and (ii) real-life patients' treatment practices. A cross-sectional study involved 138 adult HAE patients (88 females, 50 males) treated in six regional HAE centers in Poland. Consecutive patients during routine follow-up visits underwent a structured medical interview on the clinical characteristics of the course and treatment of HAE attacks within the last six months. A total of 118 of 138 patients was symptomatic. They reported in total 2835 HAE attacks predominantly peripheral and abdominal, treated with plasma-derived C1-INH (61.4%), icatibant (36.7%) and recombinant C1-INH (1.9%). An amount of 116 patients carried the rescue medication with them while traveling, and 74 patients self-administrated on demand treatment. There were twice as many symptomatic women (n = 78) as there were men (n = 40). Women treated their HAE attacks significantly more often than men. Older patients (≥65 years) reported a longer delay in diagnosis, and practiced the self-administration of rescue medication less frequently in comparison to other patients. Clinical features of the surveyed population are similar to other European, but not Asian, HAE patient groups. Self-administration still remains an unmet medical need. Some distinct HAE patients may require special attention due to the severe course of the disease (females) or a delay in diagnosis (the elderly).

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.

National Audit of a Hereditary and Acquired Angioedema Cohort in New Zealand

BACKGROUND

HAE leads to significant morbidity and mortality from unpredictable intermittent peripheral, abdominal and laryngeal swelling. Access to appropriate healthcare and effective therapies which can prevent and treat attacks, reduce the suffering and greatly improve quality of life. Although treatments such as C1 inhibitor (Berinert®), and Icatibant® are available in New Zealand (Aotearoa), there is no published data available on their use.

AIMS

This study presents a national audit of Hereditary Angioedema (HAE) and Acquired Angioedema (AAE) in 2019.

RESULTS

The total number of known adult (48) and children (3) HAE and Acquired Angioedema (3) patients is 54. Of these, 41/ 54 (75%) of HAE and AAE patients were recruited to the audit. Icatibant® has been available for treatment of acute HAE attacks since 2016, and is now used in 73% of HAE patients. Icatibant® is also used by patients for laryngeal attacks in the community, who may not then present to hospital. Androgens are used in half of the patients as prophylaxis but 33% of the latter were identified as not having regular liver ultrasound screening. Tranexamic acid is used as prophylaxis in one fifth of patients. Participants have had 40 children, half of whom may be affected. Three have been diagnosed with HAE, suggesting that the majority have not yet been tested.

CONCLUSIONS

Corrective actions arising from this audit will improve our capacity to provide long term care for HAE patients and their families. This article is protected by copyright. All rights reserved.

Demographic and clinical characteristics of patients with hereditary angioedema in Canada

BACKGROUND

Data on the clinical and demographic features of Canadian patients with hereditary angioedema (HAE) are lacking.

OBJECTIVE

To describe the clinical and demographic features in a large Canadian HAE cohort and compare them with patients with HAE in other countries.

METHODS

An online questionnaire was distributed to the members of 2 Canadian HAE patient groups to collect information on demographics and HAE clinical characteristics. All participants 18 years of age or older with HAE type I or II were eligible. Frequency, location, prodromes, and triggers of HAE attacks, including types of HAE treatment, were characterized.

RESULTS

Among the 90 participants who completed the online survey, 57% self-identified as having HAE type 1 and 26% HAE type II. The average diagnostic delay was 11 years. In the preceding 6 months, 24% of the participants had no attacks and 35% experienced greater than 5 attacks. The most frequently affected regions of the body were the abdomen (83%), arms orlegs (63%), face (41%), and larynx or throat (41%). Approximately 87% of the participants reported having access to C1 inhibitor at home, and 69% reported using it for long-term prophylaxis.

CONCLUSION

Canadian patients with HAE share common clinical characteristics with patients with HAE in other countries. They had a delay in HAE diagnosis and a high burden of disease, as indicated by the high frequency of attacks in the preceding 6 months. This study provides a better understanding of the demographic and clinical characteristics of Canadian patients with HAE.

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.

A Germany-wide survey study on the patient journey of patients with hereditary angioedema

Background

Hereditary angioedema (HAE) is a rare genetic disease and characterized by clinical features such as paroxysmal, recurrent angioedema of the skin, the gastrointestinal tract, and the upper airways. Swelling of the skin occurs primarily in the face, extremities and genitals. Gastrointestinal attacks are accompanied by painful abdominal cramps, vomiting and diarrhea. Due to the low prevalence and the fact that HAE patients often present with rather unspecific symptoms such as abdominal cramps, the final diagnosis is often made after a long delay. The aim of this German-wide survey was to characterize the period between occurrence of first symptoms and final diagnosis regarding self-perceived health, symptom burden and false diagnoses for patients with HAE.

Results

Overall, 81 patients with HAE were included and participated in the telephone-based survey. Of those, the majority reported their current health status as “good” (47.5%) or “very good” (13.8%), which was observed to be a clear improvement compared to the year before final diagnosis (“good” (16.3%), “very good” (11.3%)). Edema in the extremities (85.2%) and in the gastrointestinal tract (81.5%) were the most currently reported symptoms and occurred earlier than other reported symptoms (mean age at onset 18.1 and 17.8 years, respectively). Misdiagnoses were observed in 50.6% of participating HAE patients with appendicitis and allergy being the most frequently reported misdiagnoses (40.0 and 30.0% of those with misdiagnosis, respectively). Patients with misdiagnosis often received mistreatment (80.0%) with pharmaceuticals and surgical interventions as the most frequently carried out mistreatments (65.6 and 56.3% of those with mistreatment, respectively). The mean observed diagnostic delay was 18.1 years (median 15.0 years). The diagnostic delay was higher in older patients and index patients.

Conclusions

This study showed that self-perceived status of health for patients is much better once the final correct diagnosis has been made and specific treatment was available. Further challenge in the future will still be to increase awareness for HAE especially in settings which are normally approached by patients at occurrence of first symptoms to assure early referral to specialists and therefore increase the likelihood of receiving an early diagnosis.

Modeling Cost-Effectiveness of On-Demand Treatment for Hereditary Angioedema Attacks

BACKGROUND

Hereditary angioedema (HAE) is a rare C1-inhibitor (C1-INH) deficiency disease. Low levels of functional C1-INH can lead to recurrent attacks of severe swelling occurring in areas such as the limbs, face, gastrointestinal tract, and throat. These attacks are both painful and disabling and, if not treated promptly and effectively, can result in hospitalization or death. Agents targeting the specific physiologic pathway of HAE attacks can offer improved outcomes with limited side effects compared with nonspecific therapies. However, these treatments display varying efficacy in HAE patients, including the need to redose or seek additional care if the treatment does not resolve symptoms effectively.

OBJECTIVE

To analyze the expected cost and utility per HAE attack when treated on-demand with HAE therapies indicated for the treatment of acute attacks.

METHODS

A decision-tree model was developed using TreeAge Pro software. Four on-demand HAE treatments were included: ecallantide, icatibant, plasma-derived (pd)C1-INH, and recombinant human (rh)C1-INH. The model uses probabilities for redosing, self-administration versus health care provider administration, and risk of hospitalization. Costs within the model consisted of the HAE treatments and associated health care system expenses. Nonattack baseline utility and attack utility were implemented for effectiveness calculations; time to attack resolution was considered as well. Effectiveness and overall costs per attack were calculated and used to estimate cost per quality-adjusted life-year (QALY). Variability and ranges in cost-effectiveness were determined using probabilistic sensitivity analyses. Finally, a budget impact model for a health plan with 1 million covered lives was also developed.

RESULTS

The base case model outputs show costs and calculated effectiveness per attack at $12,905 and 0.806 for rhC1-INH, $14,806 and 0.765 for icatibant, $14,668 and 0.769 for pdC1-INH, and $21,068 and 0.792 for ecallantide, respectively. Cost per QALY was calculated using 26.9 attacks per person-year, leading to results of $420,941 for rhC1-INH, $488,349 for icatibant, $483,892 for pdC1-INH, and $689,773 for ecallantide. Sensitivity analyses demonstrate that redose rates (from 3% for rhC1-INH to 44% for icatibant) are a primary driver of variability in cost-effectiveness. Annual health plan costs from the budget impact model are calculated as $6.94 million for rhC1-INH, $7.97 million for icatibant, $7.90 million for pdC1-INH, and $11.33 million for ecallantide.

CONCLUSIONS

Accounting for patient well-being and additional cost components of HAE attacks generates a better estimation of cost-effectiveness than drug cost alone. Results from this model indicate that rhC1-INH is the dominant treatment option with lower expected costs and higher calculated effectiveness than comparators. Further analyses reinforce the idea that low redose rates contribute to improved cost-effectiveness.

DISCLOSURES

Funding support was contributed by Pharming Healthcare. Relan and Adams are employed by Pharming Healthcare. Tyson and Magar are employed by AHRM, which received fees to perform the analysis and develop the manuscript. Bernstein reports grants, personal fees, and nonfinancial support from Shire, CSL Behring, and Pharming Healthcare; grants and personal fees from Biocryst; and nonfinancial support from HAEA, unrelated to this study.

Cost-Effectiveness of Prophylactic Medications for the Treatment of Hereditary Angioedema Due to C1 Inhibitor Deficiency: A Real-World U.S. Perspective

DISCLOSURES

No funding supported the writing of this commentary. The author reports personal fees from BioCryst, CSL Behring, Shire, and Pharming and grants from Ionis. He is chair of the US HAEA Medical Advisory Board and scientific advisor for HAE International.

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.

Real-world outcomes in hereditary angioedema: first experience from the Icatibant Outcome Survey in the United Kingdom

Background

Hereditary angioedema (HAE) is a potentially life-threatening, bradykinin-mediated disease, often misdiagnosed and under-treated, with long diagnostic delays. There are limited real-world data on best-practice management of HAE in the UK.

Objectives

To characterize the clinical profile, management and outcomes of patients with HAE type I and II from three specialist centres in the UK using data from the Icatibant Outcome Survey (IOS; Shire, Zug, Switzerland), an international observational study monitoring safety and effectiveness of icatibant, a selective bradykinin B2 receptor antagonist.

Methods

We performed retrospective analyses of IOS data for patients with HAE type I and II from three centres in the UK and compared UK data with pooled IOS data from 10 countries (48 centres).

Results

Analyses included 73 UK and 579 non-UK patients with HAE type I or II. Median diagnostic delay was 6.2 and 5.9 years, respectively. Analysis of data collected from February 2008 to July 2016 included 286 icatibant-treated attacks in 58 UK patients and 2553 icatibant-treated attacks in 436 non-UK patients (median of 3.0 attacks per patient in both groups). More attacks were treated by icatibant self-administration in UK patients (95.8%) than in non-UK patients (86.8%, p < 0.001). Time to icatibant treatment, time to resolution and attack duration were not significantly different in the UK versus non-UK patients.

Conclusion

UK patients from the specialist centres studied report similar diagnostic delay and similar icatibant treatment outcomes to their non-UK counterparts. However, improvements in the timely diagnosis of HAE are still required.

Trial registration ClinicalTrials.gov NCT01034969

Disease Severity, Activity, Impact, and Control and How to Assess Them in Patients with Hereditary Angioedema

Hereditary angioedema (HAE) is a group of rare, potentially life-threatening, and frequently debilitating diseases characterized by recurrent, and often with an unpredictable onset, of swelling attacks. HAE is heterogeneous, with considerable differences between its subtypes, patients, and even within the same patient over time. During the past few years, several new on demand and prophylactic therapies have become available for HAE, allowing for individualized treatment. Therefore, to optimize HAE management, it is important to determine in all patients, the severity of their attacks, their disease activity, its therapeutic control, and its impact on their quality of life. In this manuscript, we review the existing tools to assess these aspects of HAE management, many of which are patient-reported outcome instruments. Also, we outline the current gaps of knowledge and what tools are still missing to allow for a comprehensive assessment of all patients with HAE including children.