Medical Literature - 2014

Nanda MK, Singh U, Wilmot J, Bernstein JA. 08/2014 The Annals of Allergy, Asthma & Immunology (Ann.Allergy Asthma Immunol.)

BACKGROUND: Current guidelines recommend short-term prophylaxis (STP) before invasive procedures to prevent hereditary angioedema (HAE) attacks; however, adherence to these guidelines may be variable because this indication lacks Food and Drug Administration approval in the United States. OBJECTIVE: To ascertain the STP experiences of patients with HAE and HAE-treating physicians.

METHODS: Online questionnaires focusing on STP experiences were distributed by the US Hereditary Angioedema Association to the first 250 patients with HAE and to registered HAE-treating physicians. SAS 9.3 was used to perform descriptive statistics and to test the difference between patients who underwent procedures and those who did not using Pearson chi(2) test, Fisher exact test, and 2-sample t test.

RESULTS: For the patient survey, 219 respondents met the criteria for HAE type 1 and 2; 37 (17%) underwent 66 invasive procedures, and all reported receiving STP. Eight patients (22%) reported failed STP, but only 3 required on-demand therapy. For STP, anabolic steroids and plasma-derived C1 inhibitor were the most and second-most commonly used, respectively. For the physician survey, 37 physicians reported caring for 433 patients with HAE. Depending on the procedure, 19% to 54% of physicians used STP and 30% to 86% prescribed on-demand therapy; 69% and 78% of physicians prescribed plasma-derived C1 inhibitor as STP for minimally invasive and invasive procedures, respectively. Physicians reported excellent efficacy for the STP treatments used.

CONCLUSION: Physicians reported excellent outcomes using primarily newer STP therapies, namely plasma-derived C1 inhibitor, which was discordant to patient-reported outcomes using older STP therapies, namely anabolic steroids. Well-controlled STP studies are needed to clarify use for patients with HAE in the United States. Copyright 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

2014 Aug;113(2):198-203

Available from: annallergy.org/article/S1081-1206%2814%2900309-3/fulltext (small fee)

Chyung Y, Vince B, Iarrobino R, Sexton D, Kenniston J, Faucette R, et al. 10/2014 Annals of Allergy, Asthma and Immunology

BACKGROUND: DX-2930 is a human monoclonal antibody inhibitor of plasma kallikrein under investigation for long-term prophylaxis of hereditary angioedema.

OBJECTIVE: To assess the safety, tolerability, pharmacokinetics, and pharmacodynamics of DX-2930 in healthy subjects.

METHODS: A single-center, double-blinded study was performed in 32 healthy subjects randomized 3:1 to receive a single subcutaneous administration of DX-2930 or placebo within 1 of 4 sequential, ascending dose cohorts (n = 8 each): 0.1, 0.3, 1.0, or 3.0 mg/kg.

RESULTS: No dose-limiting toxicity was observed. Headache was the most commonly reported treatment emergent adverse event (AE), occurring at a rate of 25% in the DX-2930- and placebo-treated groups; none were severe and all resolved. There were no serious AEs, discontinuations owing to an AE, or deaths. Two subjects had a severe AE reported as related to treatment by the blinded investigator; the 2 AEs were asymptomatic creatinine phosphokinase elevations of 902 U/L in 1 subject receiving 0.1 mg/kg DX-2930 and 1,967 U/L in 1 subject receiving placebo. For the 0.1-, 0.3-, 1.0-, and 3.0-mg/kg dose groups, respectively, mean maximum plasma concentrations were 0.6, 1.4, 5.6, and 14.5 mug/mL and mean elimination half-lives were 20.6, 16.8, 17.6, and 21.2 days. Exploratory biomarker assays, involving ex vivo activation of the kallikrein pathway, showed dose- and time-dependent inhibition of plasma kallikrein, with evidence of sustained bioactivity consistent with the pharmacokinetics profile.

CONCLUSION: A single administration of DX-2930 in healthy subjects up to doses of 3.0 mg/kg was well tolerated without dose-limiting toxicity. Pharmacokinetic and pharmacodynamic data provide evidence for a long-acting biological effect relevant to long-term prophylaxis for hereditary angioedema with C1-inhibitor deficiency.

TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT01923207. Copyright © 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Available from: annallergy.org/article/S1081-1206%2814%2900377-9/fulltext

Rubinstein E, Stolz LE, Sheffer AL, Stevens C, Bousvaros A. 4/2014 BMC Gastroenterology

BACKGROUND: Hereditary angioedema (HAE) is characterized by unpredictable attacks of debilitating subcutaneous and mucosal edema. Gastrointestinal attacks are painful, of sudden onset and often mistaken for acute abdomen leading to unnecessary surgery. The purpose of this study was to analyze symptom presentation of gastrointestinal angioedema in pediatric and adult HAE patients.

METHODS: Information collected during the clinical development of ecallantide for treatment of acute HAE attacks included affected anatomic location, accompanying symptoms, medical history, and pain assessments. Efficacy endpoints included Treatment Outcome Score (TOS, maximum score = 100; minimally important difference = 30), a point-in-time measure of treatment response, and time to treatment response.

RESULTS: Forty-nine percent of 521 HAE attacks only involved abdominal symptoms. The most commonly reported abdominal symptoms were distension (77%), cramping (73%) and nausea (67%). The most common pain descriptors were tender, tiring-exhausting, aching, cramping and sickening. White blood cell counts were elevated (>10 x 10(9)/L) in 23% of attacks (mean +/- SD: 15.1 +/- 11.27 x 10(9)/L). A high proportion of patients reported a history of abdominal surgery, including appendectomy (23%), cholecystectomy (16.4%), and hysterectomy (8.2%). Mean TOS at 4 hours post ecallantide was 77 +/- 33 versus 29 +/- 65 for placebo. Median time to significant symptom resolution was 165 minutes (95% CI 136, 167) for ecallantide versus >4 hours (95% CI 161, >4 hours) for placebo. Anaphylactic reactions occurred in 6 of the 149 treated patients.

CONCLUSIONS: HAE should be considered in the differential diagnosis of patients with recurrent discrete episodes of severe, unexplained crampy abdominal pain associated with nausea.

TRIALS REGISTRATION: The data used in the analysis were gathered across multiple clinical trials conducted during the clinical development program for ecallantide. All of the studies were conducted using Good Clinical Practices (GCP) and in accordance with the ethical principles that have their origins in the Declaration of Helsinki. Each site that participated in the clinical trials obtained the appropriate IRB or Ethics Committee approval prior to enrolling any patients. All patients provided written informed consent prior to undergoing any study-related procedures. Pediatric patients provided written assent and their parents or guardians gave written informed consent.The following trials have been registered at http://www.clinicaltrials.gov.proxy1.lib.uwo.ca EDEMA2 (identifier NCT01826916); EDEMA3 (identifier NCT00262080); EDEMA4 (identifier NCT00457015); and DX-88/19 (identifier NCT00456508).

Available from: ncbi.nlm.nih.gov/pmc/articles/PMC4101849/

Bork K. 8/2014 Current Opinion in Allergy and Clinical Immunology

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.

Available from: journals.lww.com/co-allergy/Abstract/2014/08000/An_evidence_based_therapeutic_approach_to.16.aspx (small fee)

Kim SJ, Brooks JC, Sheikh J, Kaplan MS, Goldberg BJ. 12/2014 Ann.Allergy Asthma Immunol.

BACKGROUND: Hospital admission data indicate that the angioedema incidence has increased during the past several decades. Little is known about mortality trends.

OBJECTIVES: To count the number of deaths associated with angioedema in the United States, investigate correlations with age, sex, race, and other contributory causes, and analyze trends from 1979 to 2010. METHODS: All US death certificates in which angioedema was listed as an underlying or contributing cause of death during 1979 to 2010 were analyzed. Age-adjusted mortality rates were analyzed by age, sex, and race. Other conditions designated as the underlying cause of death were investigated.

RESULTS: From 1979 to 2010, there were 5,758 deaths in which angioedema was listed as a contributing cause. The age-adjusted death rate for hereditary angioedema decreased from 0.28 (95% confidence interval [CI] 0.25-0.32) to 0.06 (95% CI 0.05-0.08) per million persons per year. Conversely, mortality for angioedema increased from 0.24 (95% CI 0.21-0.27) to 0.34 (95% CI 0.31-0.37) per million. Blacks constituted 55% of angioedema deaths that were associated with use of angiotensin-converting enzyme inhibitors. On death certificates that listed hereditary angioedema as the underlying cause of death, cancer (frequently lymphoma or leukemia) was the second most commonly listed cause.

CONCLUSION: Angioedema-associated deaths were very rare from 1979 to 2010. Hereditary angioedema deaths became even more so, whereas nonhereditary angioedema deaths increased. Risks associated with angiotensin-converting enzyme inhibitors were higher in blacks. Lack of specific coding for acquired angioedema most likely explains the observed association between cancer and hereditary angioedema. In the future, more granular coding systems may help distinguish hereditary from acquired angioedema. Copyright © 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Available from: sciencedirect.com/science/article/pii/S1081120614006371 (small fee)

Rasmussen ER, Mey K, Bygum A. 5/2014 Acta Dermato Venereologica

Angioedema is a sudden localised and often asymmetric swelling of the skin or mucous membranes caused by transient increased endothelial permeability causing plasma extravasation. In the last decades the incidence of severe angioedema involving the upper airways and even fatal outcome due to asphyxia has increased. This is mainly due to pharmaceuticals such as angiotensin converting enzyme-inhibitors, which are extensively used worldwide. Some aspects of the pathophysiology have been elucidated and the vasoactive molecule bradykinin is shown to be one of the main causative agents. The diagnosis is often delayed and traditional treatment usually ineffective. Complement C1 inhibitor concentrate and bradykinin receptor antagonists, normally used to treat patients with hereditary angioedema, have shown good results when used in patients with bradykinin-mediated angioedema. This review discusses the disease, prognosis and treatment options.

Available from: medicaljournals.se/acta/content/?doi=10.2340/00015555-1760&html=1

Feussner A, Kalina U, Hofmann P, Machnig T, Henkel G. 10/2014 Transfusion

BACKGROUND: For safe and efficacious treatment of hereditary angioedema, C1 esterase inhibitor (C1-INH) concentrates should have high purity and high amounts of functional protein. As no pharmacopoeia requirements exist for C1-INH concentrate lot release, biochemical characteristics as declared by the manufacturers may not be compared directly. This study compared the characteristics and purity profiles of four commercially available C1-INH concentrates.

STUDY DESIGN AND METHODS: The analysis included one transgenic (Ruconest) and three plasma-derived (Berinert, Cetor, Cinryze) C1-INH concentrates. C1-INH antigen concentration was determined by nephelometry, total protein (specific activity) with a Bradford assay, purity by size-exclusion chromatography and gel electrophoresis, and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry was performed.

RESULTS: Functionality (inversely proportional to antigen-to-activity ratio) was lowest for Ruconest (1.67), followed by Cetor (1.42), Berinert (1.24), and Cinryze (1.22). Specific activity (U/mg) and purity (%) were highest in Ruconest (12.13; 98.6) and Berinert (11.57; 97.0), followed by Cinryze (10.41; 89.5) and Cetor (9.01; 88.6). Main protein bands were found for all plasma-derived products at approximately 105kDa, and for Ruconest, at approximately 98kDa. Additional bands in the plasma-derived products were alpha1-antichymotrypsin, ceruloplasmin, Factor C3 (Cinryze/Cetor), and immunoglobulin heavy constant mu (Berinert).

CONCLUSION: Ruconest has a very high purity profile but is not identical to the human C1-INH protein. Of the plasma-derived products, Berinert has the highest purity profile. The impact of the nontherapeutic proteins identified has not yet been evaluated. For harmonization of the analysis for drug release, we recommend the establishment of regulatory requirements for purity determination and the implementation of threshold levels in C1-INH concentrates. Copyright © 2014 The Authors. Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

Available from: onlinelibrary.wiley.com/doi/10.1111/trf.12678/full

Kaplan AP. /2014 Chemical Immunology and Allergy

Diseases which have been demonstrated to be caused by increased plasma levels of bradykinin all have angioedema as the common major clinical manifestation. Angioedema due to therapy with angiotensin-converting enzyme (ACE) inhibitors is caused by suppressed bradykinin degradation so that it accumulates. This occurs because ACE metabolizes bradykinin by removal of Phe-Arg from the C-terminus, which inactivates it. By contrast, angioedema due to C1 inhibitor deficiency (either hereditary types I and II, or acquired) is caused by bradykinin overproduction. C1 inhibitor inhibits factor XIIa, kallikrein and activity associated with the prekallikrein-HK (high-molecular-weight kininogen) complex. In its absence, uncontrolled activation of the plasma bradykinin cascade is seen once there has been an initiating stimulus. C4 levels are low in all types of C1 inhibitor deficiency due to the instability of C1 (C1r, in particular) such that some activated C1 always circulates and depletes C4. In the hereditary disorder, formation of factor XIIf (factor XII fragment) during attacks of swelling causes C4 levels to drop toward zero, and C2 levels decline. A kinin-like molecule, once thought to be a cleavage product derived from C2 that contributes to the increased vascular permeability seen in hereditary angioedema (HAE), is now thought to be an artifact, i.e. no such molecule is demonstrable. The acquired C1 inhibitor deficiency is associated with clonal disorders of B cell hyperreactivity, including lymphoma and monoclonal gammopathy. Most cases have an IgG autoantibody to C1 inhibitor which inactivates it so that the presentation is strikingly similar to type I HAE. New therapies for types I and II HAE include C1 inhibitor replacement therapy, ecallantide, a kallikrein antagonist, and icatibant, a B2 receptor antagonist. A newly described type III HAE has normal C1 inhibitor, although it is thought to be mediated by bradykinin, as is an antihistamine-resistant subpopulation of patients with ‘idiopathic’ angioedema. The mechanism(s) for the formation of bradykinin in these disorders is unknown. Copyright © 2014 S. Karger AG, Basel.

Available from: karger.com/Article/Abstract/358619

Hofman ZL, Relan A, Hack CE. 07/2014 Clinical & Experimental Immunology (Clin.Exp.Immunol)

Hereditary angioedema (HAE) patients experience recurrent episodes of angioedema attacks that can be painful, disfiguring and even life-threatening. The disorder results from a mutation in the gene that controls the synthesis of C1-inhibitor (C1INH). C1INH is a major regulator of activation of the contact system. It is often assumed that attacks results from uncontrolled local activation of the contact system with subsequent formation of bradykinin. To evaluate the involvement of inflammatory reactions in HAE, we analysed C-reactive protein (CRP) levels. HAE patients included in a clinical database of recombinant human C1-inhibitor (rhC1INH) studies were evaluated. For the current study we analysed CRP levels when patients were asymptomatic, during a clinical attack and in a follow-up period, and correlated these with the clinical manifestations of the attack. Data from 68 HAE patients were analysed and included CRP levels on 273 occasions. While asymptomatic, 20% of the patients analysed had increased CRP. At the onset of the attack (P=0049) and during the next 24h CRP rose significantly (P=0002) in patients with an abdominal location, and post-attack levels were significantly higher in these patients than in patients with attacks at other locations (P=0034). In conclusion, CRP levels are elevated in a substantial proportion of asymptomatic HAE patients. Levels of CRP increase significantly during an abdominal attack. These data suggest low-grade systemic inflammatory reactions in HAE patients as well as a triggering event for attacks that starts prior to symptom onset. 2014 British Society for Immunology.

2014 Jul;177(1):280-286

Available from: onlinelibrary.wiley.com/doi/10.1111/cei.12314/full (small fee)

Schurmann D, Herzog E, Raquet E, Nolte MW, May F, Muller-Cohrs J, et al. 11/2014 Thrombosis and Haemostasis

Human plasma-derived C1-esterase inhibitor (C1-INH) is an efficacious and safe treatment for hereditary angioedema. However, thrombotic events in subjects treated with C1-INH at recommended or off-label, high doses have been reported. In this study, we addressed the potential prothrombotic risk of C1-INH treatment in high doses using a non-clinical rabbit model. Following intravenous infusion of C1-INH to rabbits at doses up to 800 IU/kg, the exposure and the pharmacodynamic efficacy of C1-INH in rabbits were confirmed by activity measurements of C1-esterase, and coagulation factors XIa and XIIa, respectively. Potential prothrombotic effects were assessed following induction of venous and arterial thrombosis using in vivo models of venous and arterial stasis, complemented by various in vitro assays of coagulation markers. Administration of C1-INH at doses up to 800 IU/kg did not potentiate thrombus formation during venous stasis. In contrast, inhibition of arterial occlusion was observed upon C1-INH administration when compared with isotonic saline treatment, indicating antithrombotic rather than prothrombotic activity of high dose C1-INH treatment in vivo. This was further confirmed in vitro by decreased thrombin generation, increased activated partial thromboplastin time, clotting time and clot formation time, and inhibition of platelet aggregation. No relevant changes in fibrinolysis or in the levels of thrombin-antithrombin complexes, and prothrombin fragment 1+2 were observed upon high dose C1-INH treatment. The data suggest that treatment of healthy rabbits with high doses of C1-INH could potentially inhibit coagulation and thrombus formation rather than induce a prothrombotic risk.

Available from: th.schattauer.de/en/contents/archive/manuscript/22277.html

de Maat S, de Groot PG, Maas C. 11/2014 Seminars in Thrombosis and Hemostasis

When the contact system assembles and activates on negatively charged surface materials, plasma coagulation rapidly follows. This mechanism is redundant for hemostasis but mediates pathological thrombus formation, as was reported in a multitude of in vivo studies. The epidemiological data are presently scarce to firmly support a role for the contact system in human thrombotic disease, while its physiological function and mode of activation remains mysterious. Besides its role in blood coagulation in vitro, the contact system is responsible for the production of bradykinin. This inflammatory peptide is involved in episodes of pathological tissue swelling in (hereditary) angioedema, but potentially also in the physiological regulation of vascular permeability. A body of evidence indicates that contact system factors are recruited to the surface of activated endothelial cells, where proteins that are locally released can activate them. Furthermore, clinical and biochemical studies indicate that plasmin, the effector enzyme of the fibrinolytic system, can evoke contact system activation. This auxiliary role for plasmin may so far not have been fully appreciated in pathophysiology. To conclude this review, we propose a complementary model for contact system activation on the endothelial cell surface that is initiated by plasmin activity. Copyright Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

Available from: europepmc.org/abstract/med/25389102 (small fee)

Hassen GW, Tu TJ, Wei DH, Hwang A, Lamothe R, Costea A, et al. 10/2014 J.Emerg.Med.

BACKGROUND: Approximately 2% of angioedema (AE) patients have a hereditary or an acquired deficiency of the complement 1 (C1) esterase inhibitor (C1 INH) gene. Some case reports indicate an association between angiotensin-converting enzyme inhibitor (ACEI) use and exacerbation of hereditary AE (HAE).

OBJECTIVE: The aim of this retrospective study is to investigate the association between HAE and ACEI use in a larger patient population.

METHODS: A retrospective chart review of patients who presented with AE and patients with diagnostic serum assays for functional C1 INH, C1 INH antigenic protein, C1q, C1q immune complex (C1q IC), and complement 4 (C4) regardless of medical complaint. Descriptive statistics were used to analyze the data.

RESULTS: A total of 1594 patients had complement levels measured (136 C1 INH, 55 C1q, 10 C1q IC, and 1500 C4), of which 156 (9.7%) patients presented with AE. Angiotensin-converting enzyme inhibitor use was documented in 747 (47%) patients. Low C1 INH was detected in one patient with recurrent AE who was not taking ACEI. Another patient who presented with recurrent AE was found to have systemic lupus erythematosus with abnormal C4, C1q, and C1q IC, but normal C1 INH. A low C4 level was present in 94 patients, 4 of which had AE.

CONCLUSIONS: The risk of exacerbating HAE by ACEI might be present, but we did not find any association in this retrospective study. Further studies are needed to determine the existence of this association. Copyright 2013 Elsevier Inc. All rights reserved.

2013 Oct;45(4):602-608

Available from: jem-journal.com/article/S0736-4679%2813%2900577-5/fulltext (small fee)

Bernstein JA, Manning ME, Li H, White MV, Baker J, Lumry WR, et al. 01/2014 J.Allergy Clin.Immunol.Pract.

BACKGROUND: Nanofiltered C1 inhibitor (human) is approved in the United States for routine prophylaxis of angioedema attacks in patients with hereditary angioedema, a rare disease caused by a deficiency of functional C1 inhibitor.

OBJECTIVE: To assess the safety of escalating doses of nanofiltered C1 inhibitor (human) in patients who were not adequately controlled on the indicated dose (1000 U every 3 or 4 days).

METHODS: Eligible patients had >1 attack/month over the 3 months before the trial. Doses were escalated to 1500 U every 3 or 4 days for 12 weeks, at which point, the patients were evaluated. If treatment was successful (1 attack/month were eligible for further escalation to 2000 U and then 2500 U.

RESULTS: Twenty patients started at 1500 U; 13 were escalated to 2000 U, and 12 were escalated to 2500 U. Eighteen patients reported adverse events. Two patients reported 4 serious adverse events (cerebral cystic hygroma, laryngeal angioedema attack, anemia, and bile duct stone) that were considered by investigators to be unrelated to treatment. Notably, there were no systemic thrombotic events or discontinuations due to adverse events. Fourteen patients were treated successfully (70%), continued to the follow-up period at the investigator’s discretion, or experienced a reduction in attacks of >1.0/month.

CONCLUSIONS: Dose escalation of nanofiltered C1 inhibitor (human) up to 2500 U was well tolerated and reduced attack frequency in the majority of patients. Copyright 2013 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

2014 Jan-Feb;2(1):77-84

Available from: jaci-inpractice.org/article/S2213-2198%2813%2900383-8/fulltext

Emmens RW, Naaijkens BA, Roem D, Kramer K, Wouters D, Zeerleder S, et al. 6/2014 Drug Deliv.

CONTEXT: C1-esterase inhibitor (C1-inh) therapy is currently administered to patients with C1-inh deficiency through intravenous injections. The possibility of subcutaneous administration is currently being explored since this would alleviate need for hospitalization and increase mobility and well-being of patients. Recently, it was observed in pigs that C1-inh indeed can effectively be applied by subcutaneous injection. For studies on the effectiveness of C1-inh therapy for other indications than acquired and hereditary angioedema, rats are commonly used as model animal. For rats, however, subcutaneous C1-inh administration has never been investigated.

OBJECTIVE: To evaluate the efficacy of subcutaneous C1-inh administration in rats.

MATERIALS AND METHODS: Three boli of 100 U/kg human plasma-derived C1-inh were administered to Wistar rats on three consecutive days through subcutaneous injection or intravenous injection. Blood samples were collected from the tail veins 3, 4.5 or 6 h after C1-inh administration for measurement of C1-inh plasma levels. Antigen and activity levels of C1-inh of each plasma sample were determined by means of a specific ELISA.

RESULTS: For both C1-inh antigen and C1-inh activity, 21- to 119-fold higher plasma levels were measured after intravenous administration compared with subcutaneous administration. Subcutaneous administration also resulted in C1-inh plasma levels that were less stable and with decreased relative activity.

CONCLUSION: These combined results indicate that in rats, subcutaneous injections in the present formulation are not effective as alternative administration route for C1-inh.

Available from: informahealthcare.com/doi/abs/10.3109/10717544.2013.853211

Gregory C, Landmesser LM, Corrigan L, Mariano D. 1/2014 Journal of Infusion Nursing

Hereditary angioedema (HAE) is a rare, chronic disease of C1 inhibitor deficiency. Study researchers evaluated the prevalence of home and self-administration of nanofiltered, human-derived C1 esterase inhibitor infusions and the implementation of a nursing training and support program. Home administration rate increased from 49.0% to 75.8%. The percentage who self-administered increased from 20.3% to 43.9%. Doses per week averaged 1.85 at home compared with 1.40 in infusion centers and physicians’ offices. Patients required an average of 5 visits to be trained. Self-administration is a viable, feasible option in the management of HAE, which is facilitated by a nurse-managed training and support program.

Available from: journals.lww.com/journalofinfusionnursing/Citation/2014/01000/Feasibility_of_Home_Infusion_and.4.aspx (small fee)

Zotter Z, Veszeli N, Csuka D, Varga L, Farkas H. 2/2014 Orphanet Journal of Rare Diseases

BACKGROUND: Danazol, a drug extensively used in the management of hereditary angioedema due to C1 inhibitor deficiency (C1-INH-HAE), has various side effects. This study investigated the virilizing actions of this drug in 31 danazol-treated female patients with HAE-C1-INH. We compared our findings with those of healthy controls and with literature data.

METHODS: The patients were interviewed individually about the type and severity of the virilizing effects, as well as about their satisfaction with danazol therapy.

RESULTS: The average duration of danazol treatment was 10.31 years [2 to 23] and its mean daily dose was 131.7 mg [33 to 200]. The most common adverse effects were hirsutism (n=14), weight gain (n=13), and menstrual disturbances (n=8). The severity of danazol adverse effects did not differ by duration of treatment or by daily drug dose. The mean level of patient satisfaction with the treatment was high. The comparison of age-matched healthy controls and of HAE-C1-INH patients receiving danazol did not demonstrate a statistically higher incidence of any of the monitored symptoms in the danazol group.

CONCLUSIONS: Our findings indicate that long-term danazol treatment – using the lowest effective dose – has only a mild virilizing effect.

Available from: link.springer.com/article/10.1186/s13023-014-0205-6/fulltext.html

Bygum A. 7/2014 Acta Dermato Venereologica

Experiences from a Danish patient cohort with hereditary angioedema are reported with focus on home therapy and burden of illness. Eighty patients have been prospectively followed over 11 years, having experienced a total of 7,809 attacks over 469 patient years. More than half of the patients stopped long-term prophylaxis with danazol or tranexamic acid and changed treatment regimen to on-demand treatment with C1 inhibitor concentrate or icatibant. At least 10% of the attacks remained un-treated. More than half of the patients felt that hereditary angioedema had a significant psychological impact on their lives and restricted their physical activities. By December 2012, a total of 39 patients (49%) were practicing home treatment of acute attacks. Home therapy reduced the mean number of acute hospital visits by 84% and significantly improved burden of illness items. In conclusion, home therapy has profoundly improved the lives of hereditary angioedema patients.

Available from: medicaljournals.se/acta/content/?doi=10.2340/00015555-1743&html=1

Psarros F, Koutsostathis N, Farmaki E, Speletas MG, Germenis AE. 10/2014 International Archives of Allergy and Immunology

BACKGROUND: No published data presently exist concerning hereditary angioedema (HAE) in Greece. The aim of this study was to present the results from patients recorded by the Greek Hereditary Angioedema Registry over the last 3 years (July 2010 to June 2013).

METHODS: A systematic recording of HAE cases was undertaken following a physician awareness campaign and confirmation of diagnosis. A questionnaire was also used for the assessment of key parameters of the patients’ disease-specific quality of life.

RESULTS: One hundred and sixteen patients from 41 non-related families were recorded. There were 33 (80.5%) families with type I HAE, 7 (17%) with type II HAE and 1 (2.5%) with non-C1 inhibitor (C1-INH), non-FXII HAE. Two further non-C1-INH, non-FXII HAE sporadic cases were recorded. An investigation of non-symptomatic family members revealed another 6 asymptomatic individuals with C1-INH deficiency. The average delay in diagnosis was 16.5 years and the incidence of death in the families of patients was 1 for every 2 families. The use of newer therapeutic agents seems to fall significantly short of the existing needs. HAE was found to affect the quality of life slightly in 14%, greatly in 63% and significantly in 23% of the patients.

CONCLUSION: Until recently, there has been a significant degree of underdiagnosis of HAE in Greece. Very low compliance with the provisions of the applicable international guidelines and consensus positions, with adverse consequences on the patients’ quality of life, was also observed. The centralized model we used to uncover the patients could be effective in other countries presenting with comparable disease characteristics. Copyright © 2014 S. Karger AG, Basel.

Available from: karger.com/Article/Abstract/366276

Altman KA, Naimi DR. 5/2014 Current Medical Research and Opinion

BACKGROUND: Angioedema is a serious medical condition characterized by recurrent non-pitting tissue edema. Hereditary (HAE) forms of this disorder are potentially fatal.

METHODS: PubMED, Up to Date and Cochrane Library databases were used to identify scholarly peer reviewed original research or review articles on angioedema. Search terms used were: angioedema, HAE, ACE inhibitor induced angioedema, acquired angioedema, type III HAE (now termed HAE with normal C1-INH), diagnosis of HAE, and treatment of HAE. Inclusive dates of the search were 1946 through 2013. Articles on urticaria were excluded.

RESULTS: The pathophysiology, clinical manifestations, differential diagnosis and treatments of angioedema are presented. Three variants of HAE are discussed and differentiated from acquired, ACE induced and allergic types of angioedema. Emphasis is placed on understanding that HAE is mediated by bradykinin, not histamine, and is therefore unresponsive to antihistamines, corticosteroids and epinephrine. In contrast, newer therapies that replace C1-INH or block bradykinin production or action are the appropriate treatments for prophylaxis and acute treatment of HAE.

CONCLUSION: Recognition of HAE by primary care providers and distinguishing it from allergic histamine mediated angioedema is essential in preventing recurrent attacks and avoiding inappropriate therapy, and may be life-saving.

Available from: informahealthcare.com/doi/abs/10.1185/03007995.2013.879441

Suffritti C, Zanichelli A, Maggioni L, Bonanni E, Cugno M, Cicardi M. 12/2014 Clinical and Experimental Allergy

BACKGROUND: The inherited deficiency of C1-inhibitor (C1-INH), which can be quantitative (type I) or qualitative (type II), is characterized by recurrent attacks of oedema, and it is known as hereditary angioedema due to C1-INH deficiency (HAE-C1-INH). The frequency of symptoms varies widely among patients and in the same patient during life.

OBJECTIVE: To identify laboratory markers of disease severity in HAE-C1-INH patients.

METHODS: We studied 162 patients with differently severe HAE-C1-INH during remission, 31 HAE-C1-INH patients during attacks, and 81 normal controls, evaluating complement parameters, spontaneous plasma kallikrein activity, the capacity of plasma to inhibit exogenous kallikrein activity, and cleavage of high-molecular-weight kininogen (HK). Sixty-five HAE-C1-INH patients were screened for mutations in the C1-INH gene.

RESULTS: As expected, plasma C1-INH levels and activity and C4 levels were low in the HAE-C1-INH patients. Spontaneous plasma kallikrein activity in patients in remission was higher than in controls (P = 0.001) and increased during acute attacks (P = 0.01), whereas the capacity of inhibiting kallikrein activity was lower in patients in remission than in controls (P = 0.001) and further reduced during attacks (P = 0.001). HAE-C1-INH patients in remission had higher levels of cleaved HK than controls (P = 0.001), and these further increased during acute attacks (P = 0.001). Cleaved HK levels were higher in highly symptomatic HAE-C1-INH patients than in those with less frequent attacks (P = 0.001). Thirty-five different mutations in the C1-INH gene were equally distributed in patients with different attack frequencies.

CONCLUSIONS: Measuring plasma levels of cleaved HK may be a sensitive mean of assessing disease severity in HAE-C1-INH patients.Copyright © 2014 John Wiley & Sons Ltd.

Available from: onlinelibrary.wiley.com/wol1/doi/10.1111/cea.12293/full

Farkas H, Csuka D, Veszeli N, Zotter Z, Szabo E, Varga L. 5/2014 Allergy and Asthma Proceedings

Conestat alfa, a recombinant human C1 inhibitor (rhC1-INH) is a novel therapeutic option for the acute treatment of hereditary angioedema due to C1-INH (HAE-C1-INH) deficiency. Our aim was to investigate the efficacy and safety profile of conestat alfa in patients with HAE-C1-INH, under real-life conditions. We analyzed 65 edematous episodes requiring acute treatment and occurring in two female HAE-C1-INH patients. The patients were treated at home with rhC1-INH per occasion. They recorded the time of rhC1-INH administration, the time to the onset of improvement, and time to the complete resolution of symptoms, as well as the side effects. Symptom severity and patient satisfaction were measured with a visual analog scale (VAS). Thirty-three HAE attacks occurred in submucosal tissue, 17 in subcutaneous tissue, and 15 had mixed locations. After the administration of rhC1-INH, clinical symptoms improved within 0.50 (0.17-4.50 hours) hours and resolved completely within 9.00 (1.67-58.75 hours) hours. The time between the onset of the attack and the administration of rhC1-INH was correlated with the time when the symptoms stopped worsening (R = 0.3212; p = 0.0096) and the time to complete resolution of the symptoms (R = 0.4774; p < 0.0001). The time to response to the drug differed with attack location. The efficacy and safety of rhC1-INH persisted after repeated use. None of the patients experienced a recurrence of the HAE attack or drug-related systemic adverse events. The mean VAS score of patient satisfaction was 93.14. Home treatment with rhC1-INH was an effective and well-tolerated therapy for all types of HAE attacks.

Available from: dx.doi.org/10.2500/aap.2014.35.3743

Campos RA, Valle SO, Franca AT, Cordeiro E, Serpa FS, Mello YF, et al. /2014 Sao Paulo Medical Journal

CONTEXT AND OBJECTIVE: Hereditary angioedema (HAE) with C1 inhibitor deficiency manifests as recurrent episodes of edema involving the skin, upper respiratory tract and gastrointestinal tract. It can be lethal due to asphyxia. The aim here was to evaluate the response to therapy for these attacks using icatibant, an inhibitor of the bradykinin receptor, which was recently introduced into Brazil.

DESIGN AND SETTING: Prospective experimental single-cohort study on the efficacy and safety of icatibant for HAE patients.

METHODS: Patients with a confirmed HAE diagnosis were enrolled according to symptoms and regardless of the time since onset of the attack. Icatibant was administered in accordance with the protocol that has been approved in Brazil. Symptom severity was assessed continuously and adverse events were monitored.

RESULTS: 24 attacks in 20 HAE patients were treated (female/male 19:1; 19-55 years; median 29 years of age). The symptoms were: subcutaneous edema (22/24); abdominal pain (15/24) and upper airway obstruction (10/24). The time taken until onset of relief was: 5-10 minutes (5/24; 20.8%); 10-20 (5/24; 20.8%); 20-30 (8/24; 33.4%); 30-60 (5/24; 20.8%); and 2 hours (1/24; 4.3%). The time taken for complete resolution of symptoms ranged from 4.3 to 33.4 hours. Adverse effects were only reported at injection sites. Mild to moderate erythema and/or feelings of burning were reported by 15/24 patients, itching by 3 and no adverse effects in 6.

CONCLUSION: HAE type I patients who received icatibant responded promptly; most achieved improved symptom severity within 30 minutes. Local adverse events occurred in 75% of the patients.

Available from: scielo.br/scielo.php?script=sci_arttext&pid=S1516-31802014000500261

Pedrosa M, Lobera T, Panizo C, Jurado J, Caballero T. 01/2014 The Journal of Investigational Allergology and Clinical Immunology (J.Investig.Allergol.Clin.Immunol.)

2014;24(4):271-273

Available from: jiaci.org/issues/vol24issue4/vol24issue04-9.htm

Aberer W, Maurer M, Reshef A, Longhurst H, Kivity S, Bygum A 03/2014 Wiley

BACKGROUND: Historically, treatment for hereditary angioedema (HAE) attacks has been administered by healthcare professionals (HCPs). Patient self-administration could reduce delays between symptom onset and treatment, and attack burden. The primary objective was to assess the safety of self-administered icatibant in patients with HAE type I or II. Secondary objectives included patient convenience and clinical efficacy of self-administration.

METHODS: In this phase IIIb, open-label, multicenter study, adult patients were trained to self-administer a single 30-mg icatibant subcutaneous injection to treat their next attack. Icatibant-naive patients were treated by an HCP prior to self-administration. Evaluations included adverse event (AE) reporting, a validated questionnaire for convenience, and visual analog scale for efficacy.

RESULTS: A total of 151 patients were enrolled; 104 had an attack requiring treatment during the study, and 97 patients (19 naive) were included in the self-administration cohort. Recurrence or worsening of HAE symptoms (22 of 97) was the most commonly reported AE; rescue medications including icatibant (N = 3) and C1-inhibitor concentrate (N = 6) were used in 13 cases. Overall, 89 of 97 patients used a single injection of icatibant. No serious AEs or hospitalizations were reported. Most patients (91.7%) found self-administration preferable to administration in the clinic. The median time to symptom relief (3.8 h) was comparable with results from controlled trials of icatibant.

CONCLUSIONS: With appropriate training, patients were successfully able to recognize HAE attacks and decide when to self-administer icatibant. This, coupled with the patient-reported high degree of satisfaction, convenience and ease of use supports the adoption of icatibant self-administration in clinical practice.

Mar;69(3):305-314

Online access: onlinelibrary.wiley.com/doi/10.1111/all.12303/full (small fee)

Bouckaert M, Wood NH, Khammissa R, Lemmer J, Feller L. 10/2014 SADJ: journal of the South African Dental Association = tydskrif van die Suid-Afrikaanse Tandheelkundige Vereniging

Angioedema refers to a localized oedematous swelling of subcutaneous or submucosal tissues, caused by dilatation and increased permeability of blood vessels, usually mediated either by histamine or by bradykinin. Deficiency or loss of functional activity of the complement component C1 esterase inhibitor (C1-INH) affects multiple systems, including the kallikrein-kinin, complement, coagulation and fibrinolytic pathways, and in the context of angioedema, the result is increased production and release of bradykinin and other vasoactive substances such as C3a. Owing to impairment of C1-INH, factors Xlla and kallikrein, by a positive feedback mechanism, bring about persistent activation of the kallikrein-kinin pathway with amplification of production of bradykinin, resulting in angioedema. Histamine can cause histaminergic angioedema. As the name implies, this oedema is caused by degranulation of mast cells/basophils as a result of an IgE-dependant allergic reaction to extracts of food, drugs, infectious agents, or to physical stimulation; or as the result of direct degranulation of mast cells/basophils independently of IgE, caused by releasing agents such as opiates, antibiotics or radiocontrast media. As dental, oral and maxillofacial operative procedures may trigger the development of angioederria in susceptible individuals, the dental practitioner should be familiar with its signs and symptoms, its pathophysiology and with the firstline treatment of this disorder.

Available from: scielo.org.za/scielo.php?script=sci_arttext&pid=S0011-85162014000900011

Bork K. 5/2014 Immunotherapy

Hereditary angioedema (HAE) is a relatively rare autosomal dominant disorder that is typically characterized by recurrent episodes of edema in various body locations. It is most commonly caused by an inherited deficiency of functionally active C1 esterase inhibitor (C1-INH). Replacement therapy with a human plasma-derived C1-INH concentrate is recommended for the treatment and prophylaxis of acute attacks of HAE due to C1-INH deficiency (HAE-C1-INH). This article will discuss the current therapies available for the treatment of HAE-C1-INH, latest treatment guidelines, results of several studies demonstrating the efficacy and safety of the plasma-derived, pasteurized and nanofiltered C1-INH concentrate Berinert() (CSL Behring GmBH, Marburg, Germany), and future perspectives for the treatment and management of HAE-C1-INH.

Available from: futuremedicine.com/doi/pdf/10.2217/imt.14.33

Martinez-Saguer I, Cicardi M, Suffritti C, Rusicke E, Aygoren-Pursun E, Stoll H, et al. 06/2014 Transfusion

BACKGROUND: Hereditary angioedema (HAE) is a rare disease caused by C1-esterase inhibitor (C1-INH) deficiency, characterized by periodic attacks of acute edema affecting subcutaneous (SC) tissues and mucous membranes. Human C1-INH concentrate given intravenously (IV) is effective and safe, but venous access may be difficult. We compared SC and IV administration of human pasteurized C1-INH concentrate with respect to pharmacokinetics, pharmacodynamics, and safety.

STUDY DESIGN AND METHODS: This was a prospective, randomized, open-label, crossover study. Twenty-four subjects with mild or moderate HAE were randomly assigned during an attack-free interval to receive 1000 units of human pasteurized C1-INH concentrate IV or SC. Plasma levels of C1-INH activity and antigen, C4 antigen, cleaved high-molecular-weight kininogen (clHK), and C1-INH antibodies were measured.

RESULTS: The mean relative bioavailability of functional C1-INH after SC administration was 39.7%. Maximum C1-INH activity after SC administration occurred within 48 hours and persisted longer than after IV administration. C4 antigen levels increased and clHK levels decreased after IV and SC administration, indicating the pharmacodynamic action of C1-INH. The mean half-life of functional C1-INH was 62 hours after IV administration and 120 hours after SC administration (p=0.0595). C1-INH concentrate was safe and well tolerated when administered via both routes. As expected, SC administration resulted in a higher incidence of injection site reactions, all of which were mild.

CONCLUSION: With a relative bioavailability of 39.7%, SC administration of human pasteurized C1-INH yields potentially clinically relevant and sustained plasma levels of C1-INH and is safe and well tolerated. 2013 The Authors. Transfusion published by Wiley Periodicals, Inc. on behalf of AABB.

2014 Jun;54(6):1552-1561

Available from: onlinelibrary.wiley.com/doi/10.1111/trf.12501/full

Wadelius M, Marshall SE, Islander G, Nordang L, Karawajczyk M, Yue QY, et al. 10/2014 Clinical Pharmacology and Therapeutics

Angioedema is a potentially life-threatening adverse reaction to angiotensin-converting enzyme inhibitors and angiotensin receptor blockers. To study the genetic etiology of this rare adverse event, international consortia and multicenter recruitment of patients are needed. To reduce patient heterogeneity, we have standardized the phenotype. In brief, it comprises swelling in the head and neck region that first occurs during treatment. It should not coincide with urticaria or have another likely cause such as hereditary angioedema.

Available from: ncbi.nlm.nih.gov/pmc/articles/PMC4172548/

Tradtrantip L, Asavapanumas N, Phuan PW, Verkman AS /2014 PloS one

Neuromyelitis optica (NMO) is an autoimmune demyelinating disease of the central nervous system in which binding of anti-aquaporin-4 (AQP4) autoantibodies (NMO-IgG) to astrocytes causes complement-dependent cytotoxicity (CDC) and inflammation resulting in oligodendrocyte and neuronal injury. There is compelling evidence for a central role of complement in NMO pathogenesis. Here, we evaluated the potential of C1-esterase inhibitor (C1-inh) for complement-targeted therapy of NMO. C1-inh is an anti-inflammatory plasma protein with serine protease inhibition activity that has a broad range of biological activities on the contact (kallikrein), coagulation, fibrinolytic and complement systems. C1-inh is approved for therapy of hereditary angioedema (HAE) and has been studied in a small safety trial in acute NMO relapses (NCT 01759602). In vitro assays of NMO-IgG-dependent CDC showed C1-inh inhibition of human and rat complement, but with predicted minimal complement inhibition activity at a dose of 2000 units in humans. Inhibition of complement by C1-inh was potentiated by ~10-fold by polysulfated macromolecules including heparin and dextran sulfate. In rats, intravenous C1-inh at a dose 30-fold greater than that approved to treat HAE inhibited serum complement activity by <5%, even when supplemented with heparin. Also, high-dose C1-inh did not reduce pathology in a rat model of NMO produced by intracerebral injection of NMO-IgG. Therefore, although C1r and C1s are targets of C1-inh, our in vitro data with human serum and in vivo data in rats suggest that the complement inhibition activity of C1-inh in serum is too low to confer clinical benefit in NMO.

Available from: journals.plos.org/plosone/article?id=10.1371/journal.pone.0106824

Lumry WR, Miller DP, Newcomer S, Fitts D, Dayno J. 9/2014 Allergy and Asthma Proceedings

Patients with hereditary angioedema (HAE) have impaired health-related quality of life (HRQoL), but the effect of preventative treatment strategies on HRQoL has not been evaluated. This study was designed to evaluate the effect of routine prevention therapy with nanofiltered C1 inhibitor (C1 INH-nf; human) on the HRQoL of patients with HAE. Thiry-six-item Short Form (SF-36) Version 1.0 questionnaires were administered at the beginning and end of two 12-week treatment periods in this multicenter, randomized, placebo-controlled, crossover study. Patients (n = 22) received intravenous injections of 1000 U of C1 INH-nf or placebo every 3-4 days for 12 weeks and then crossed over to the other treatment arm for a second 12-week period. Patients could receive open-label C1 INH-nf (1000 U) for the acute treatment of angioedema attacks in either arm of the study. Sixteen patients had evaluable SF-36 data. Mean physical component summary scores (PCSs) were 36.41 at baseline, 37.06 at the end of the placebo period, and 43.92 at the end of the C1 INH-nf period. Mean mental component summary scores (MCSs) were 49.90, 44.98, and 54.00, respectively. Least square mean differences (95% confidence intervals) between C1 INH-nf and placebo in norm-based SF-36 scores at the end of each treatment period were 6.55 (1.48, 11.62; p = 0.015) for PCS and 8.70 (1.67, 15.72; p = 0.019) for MCS. In a clinical trial setting, patients with HAE had significantly better HRQoL after 12 weeks of C1 INH-nf for routine prevention compared with acute treatment of individual angioedema attacks in the absence of routine prevention while on placebo. This study was a part of the clinical trial NCT01005888 registered in www.clinicaltrials.gov.

Available from: ingentaconnect.com/content/ocean/aap/2014/00000035/00000005/art00006#

Riedl MA, Bernstein JA, Li H, Reshef A, Lumry W, Moldovan D, et al. 02/2014 Ann.Allergy Asthma Immunol.

BACKGROUND: Hereditary angioedema (HAE), caused by C1 inhibitor (C1INH) deficiency or dysfunction, is characterized by recurrent attacks of tissue swelling affecting multiple anatomic locations. Recombinant human C1INH (rhC1INH) has been shown effective for acute treatment of HAE attacks.

OBJECTIVE: To evaluate the efficacy and safety of rhC1INH (50 IU/kg to maximum 4,200 IU/treatment) vs placebo in a larger HAE population.

METHODS: Seventy-five patients experiencing peripheral, abdominal, facial, and/or oropharyngeal laryngeal attacks were randomized (3:2) to rhC1INH (n = 44) or placebo (saline; n = 31). Efficacy was assessed by patient responses on a Treatment Effect Questionnaire (TEQ) and visual analog scale (VAS). Safety also was evaluated.

RESULTS: Median (95% confidence interval) time to beginning of symptom relief at the primary attack location was 90 minutes (61-150) in rhC1INH-treated patients vs 152 minutes (93, not estimable) in placebo-treated patients (P = .031) based on the TEQ and 75 minutes (60-105) vs 303 minutes (81-720, P = .003) based on a VAS decrease of at least 20 mm. Median time to minimal symptoms was 303 minutes (240-720) in rhC1INH-treated patients vs 483 minutes (300-1,440) in placebo-treated patients based on the TEQ (P = .078) and 240 minutes (177-270) vs 362 minutes (240, not estimable; P = .005), based on an overall VAS less than 20 mm. Overall, rhC1INH was safe and well tolerated; no thromboembolic events, anaphylaxis, or neutralizing antibodies were observed.

CONCLUSION: Relief of symptoms of HAE attacks was achieved faster with rhC1INH compared with placebo as assessed by the TEQ and VAS, with a positive safety profile. Results are consistent with previous studies showing efficacy and safety of rhC1INH in patients with HAE. Copyright 2014 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

2014 Feb;112(2):163-169.e1

Available from: annallergy.org/article/S1081-1206%2813%2900925-3/fulltext (small fee)

Malbran A, Riedl M, Ritchie B, Smith WB, Yang W, Banerji A, et al. 08/2014 Clinical & Experimental Immunology (Clin.Exp.Immunol.)

Hereditary angioedema (HAE) is characterized by potentially life-threatening recurrent episodes of oedema. The open-label extension (OLE) phase of the For Angioedema Subcutaneous Treatment (FAST)-1 trial (NCT00097695) evaluated the efficacy and safety of repeated icatibant exposure in adults with multiple HAE attacks. Following completion of the randomized, controlled phase, patients could receive open-label icatibant (30mg subcutaneously) for subsequent attacks. The primary end-point was time to onset of primary symptom relief, as assessed by visual analogue scale (VAS). Descriptive statistics were reported for cutaneous/abdominal attacks 1-10 treated in the OLE phase and individual laryngeal attacks. Post-hoc analyses were conducted in patients with >5 attacks across the controlled and OLE phases. Safety was evaluated throughout. During the OLE phase, 72 patients received icatibant for 340 attacks. For cutaneous/abdominal attacks 1-10, the median time to onset of primary symptom relief was 10-20h. For laryngeal attacks 1-12, patient-assessed median time to initial symptom improvement was 03-12h. Post-hoc analyses showed the time to onset of symptom relief based on composite VAS was consistent across repeated treatments with icatibant. One injection of icatibant was sufficient to treat 882% of attacks; rescue medication was required in 53% of attacks. No icatibant-related serious adverse events were reported. Icatibant provided consistent efficacy and was well tolerated for repeated treatment of HAE attacks. 2014 British Society for Immunology.

2014 Aug;177(2):544-553

Available from: onlinelibrary.wiley.com/doi/10.1111/cei.12358/full (small fee)

Bernstein JA, Machnig T, Keinecke HO, Whelan GJ, Craig TJ 4/2014 Clinical therapeutics

BACKGROUND: Despite the worldwide obesity epidemic, there have been very few studies investigating the influence of body weight on treatment dosing and outcomes in patients with hereditary angioedema (HAE).

OBJECTIVE: The purpose of this analysis was to determine whether the standard weight-based dosing recommendation of C1 esterase inhibitor (C1-INH) concentrate (20 IU/kg) is adequate in HAE patients with a high body mass index (BMI).

METHODS: Data from patients treated for HAE attacks with 20 IU/kg of C1-INH concentrate were retrospectively analyzed from the open-label IMPACT2 study (International Multicenter Prospective Angioedema C1-INH Trial). Patients were categorized according to BMI as being normal body weight, overweight, or obese. Efficacy end points were time to onset of symptom relief and time to complete resolution of symptoms. The safety profile was evaluated according to adverse events occurring within 7 to 9 days of treatment.

RESULTS: Of 57 patients, 24 (42%) were of normal body weight, 20 (35%) were overweight, and 13 (23%) were obese. Median (95% CI) time to onset of symptom relief was 0.37 hour (0.29-0.57) in normal-weight patients, 0.48 hour (0.39-0.53) in overweight patients, and 0.58 hour (0.41-0.94) in obese patients. Median time (95% CI) to complete resolution of symptoms was 15.2 hours (9.3-23.2) in normal-weight patients, 22.6 hours (11.3-44.6) in overweight patients, and 11.0 hours (5.6-23.6) in obese patients (differences not significant). There were no relevant differences in the incidence of adverse events in normal-weight patients (54%), overweight patients (30%), and obese patients (54%).

CONCLUSIONS: Treatment of HAE attacks with weight-based doses of C1-INH concentrate provided reliable treatment response, regardless of body weight, in these patients with HAE. Copyright © 2014 Elsevier HS Journals, Inc. All rights reserved.

Available from: clinicaltherapeutics.com/article/S0149-2918(14)00074-5/fulltext

Crowther M, Bauer KA, Kaplan AP. 11/2014 Allergy and Asthma Proceedings

Thromboembolic events associated with human plasma-derived C1 esterase inhibitor (C1-INH) use in patients with hereditary angioedema (HAE) have been reported in the U.S. Food and Drug Administration (FDA) Adverse Event Reporting System database. The purpose of this article is to review and assess the strength of available evidence regarding the thrombogenicity of human plasma-derived C1-INH. A PubMed search was conducted of English language articles from January 1990 to December 2013 reporting the thrombogenicity of C1-INH. Original research articles were selected if the following criteria were met: (1) C1-INH was the focus of the study and (2) the authors addressed the pro- or antithrombotic potential of C1-INH. Additional articles on the clinical use of C1-INH in disease states other than HAE were obtained using reference lists of selected articles. Pivotal studies and prescribing information for C1-INH products were also reviewed. Limited animal and clinical data suggest that C1-INH, particularly at high doses of up to 500 U/kg (compared with the U.S. FDA-approved 20-U/kg dose), may be prothrombotic. In contrast, C1-INH has been used in some patients with myocardial infarction, ischemic stroke, sepsis, and capillary leak syndrome at off-label supratherapeutic doses (up to 100 U/kg) without evidence of a thrombogenic effect. Based on our review, thromboembolic events reported with C1-INH use are rare and patients with HAE who experienced such events often have underlying thromboembolic risk factors.

Available from: ingentaconnect.com/content/ocean/aap/2014/00000035/00000006/art00004

Shapiro RS, Zacek L 7/2014 Journal of infusion nursing : the official publication of the Infusion Nurses Society

Hereditary angioedema (HAE) is a rare disorder that causes periodic attacks of sometimes painful swelling that may affect any organ system. HAE results in significant morbidity and diminished quality of life and requires patients to seek urgent medical care. HAE can be treated with C1 esterase inhibitor concentrate (C1-INH), icatibant, and ecallantide. Recent consensus guidelines recommend that all HAE patients be considered for training in self-administration of therapy to treat acute attacks or to prevent attacks. Many patients have safely and successfully self-administered intravenous infusions of C1-INH, resulting in rapid treatment, shortened attacks, and improved quality of life. With proper patient selection and adequate guidance and follow-up, self-administered C1-INH therapy is a viable and favorable option to treat HAE, particularly in patients with a moderate to high frequency of attacks.

Available from: journals.lww.com/journalofinfusionnursing/Abstract/2014/07000/Training_Hereditary_Angioedema_Patients_to.10.aspx

Wintenberger C, Boccon-Gibod I, Launay D, Fain O, Kanny G, Jeandel PY, et al. 10/2014 Clinical and Experimental Immunology

Angioedema (AE) is a clinical syndrome characterized by localised swelling lasting several hours. The swelling is often recurring and can be lethal if it is located in the laryngeal region. Much progress has been made recently in the treatment of acute episodes, but no consensus has been reached on maintenance treatment. We have performed a national retrospective observational study to assess the use of tranexamic acid (TA) as maintenance treatment for non-histaminergic AE [hereditary AE (HAE) or idiopathic non-histaminergic AE]. Records for 64 cases were collected from 1 October 2012 to 31 August 2013; 37 of these were included (12 HAE with C1-inhibitor deficiency, six with HAE with normal C1-inhibitor and 19 idiopathic non-histaminergic AE). When treated with TA over six months, the number of attacks was reduced by 75% in 17 patients, 10 patients showed a lower level of reduction and 10 had the same number of attacks. In no instances were symptoms increased. No thromboembolic events were observed, and the main side effects were digestive in nature. Thus, TA, which is well tolerated and inexpensive, appears to be an effective maintenance treatment for some patients with HAE or idiopathic non-histaminergic AE. Copyright © 2014 British Society for Immunology.

Available from: onlinelibrary.wiley.com/doi/10.1111/cei.12379/full

Maurer M, Longhurst HJ, Fabien V, Li HH, Lumry WR. 9/2014 Allergy and Asthma Proceedings

Icatibant was efficacious and generally well tolerated for type I or II hereditary angioedema (HAE) attacks in adults in the phase III, randomized, placebo-controlled For Angioedema Subcutaneous Treatment (FAST)-3 trial. The Icatibant Outcome Survey (IOS) is an international, observational study assessing icatibant treatment of HAE attacks. We conducted a posthoc analysis to compare for the first time the treatment of HAE type I or II attacks in patients prescribed icatibant in real-world (IOS) versus controlled trial settings (FAST-3). In FAST-3, patients received icatibant administered by health care professionals (HCPs). In IOS, patients self-administered icatibant or were treated by HCPs. Median time to treatment, time to resolution (almost complete resolution [FAST-3] or complete resolution [IOS]), and attack duration in patients who were treated by an HCP were compared between IOS and FAST-3. Descriptive statistical methods compared nonlaryngeal attacks treated less than 12 hours from attack onset. Analysis included 102 patients (376 attacks) from IOS and 43 patients (43 attacks) from FAST-3 (controlled phase). All endpoints were significantly longer for patients in FAST-3 (HCP administration) versus IOS (HCP administration) (p < .001; all comparisons). For FAST-3 (HCP administered) versus IOS (HCP administered), median time from attack onset to treatment was 6.5 versus 2.0 hours, median time to symptom resolution was 8.0 versus 3.5 hours, and median attack duration was 16.9 versus 7.3 hours, respectively. For combined HCP and self-administration in IOS, these endpoints were 1.6, 4.4, and 7.8 hours, respectively. This posthoc analysis showed for the first time that type I and II HAE attacks were treated earlier with icatibant in a real-world versus a phase III setting, with a shortened time to symptom resolution and attack duration. ClinicalTrials.gov NCT00912093 (FAST-3); NCT01034969 (IOS).

Available from: ingentaconnect.com/content/ocean/aap/2014/00000035/00000005/art00007

Bhardwaj N, Craig TJ. 11/2014 Transfusion

Hereditary angioedema (HAE) is a rare autosomal dominant disorder characterized by recurrent attacks of self-limiting tissue swelling. The management of HAE has transformed dramatically with recently approved therapies in the United States. However, there is lack of awareness among physicians about these new modalities. The aim of this review is to update the practicing physician about various therapeutic options available for HAE patients. An exhaustive literature search of PubMed and OVID was performed to develop this article. Management of HAE is traditionally classified into treatment of acute attacks or on-demand therapy, short-term (preprocedural) prophylaxis, and long-term prophylaxis. Newer therapies include C1 esterase inhibitor (C1-INH) and contact system modulators, namely, ecallantide and icatibant. Recombinant C1-INH, which is available in Europe, is awaiting approval in the United States. C1-INH concentrate is approved for prophylaxis as well as on-demand therapy while ecallantide and icatibant are approved for acute treatment only. Effective HAE management further includes patient education, reliable access to specific medications, and regular follow-up to monitor therapeutic response and safety. Copyright © 2014 AABB.

Available from: onlinelibrary.wiley.com/doi/10.1111/trf.12674/full

Spickett G. 01/2014 Royal College of Physicians of Edinburgh (J.R.Coll.Physicians.Edinb.)

Urticaria, also known as hives, and angioedema, where the swelling occurs below the skin instead of on the skin, are extremely common but there is a misconception that the most likely cause is an allergic reaction. Chronic urticaria in particular is rarely due to allergy. Equally for angioedema, many will consider the exceptionally rare hereditary angioedema (HAE), but in fact other medical causes are the most likely, in particular the use of angiotensin-converting enzyme inhibitor (ACE-I) drugs. Approximately 3-5% of patients receiving ACE-I will develop angioedema at some time in the course of their treatment.1 Stress is a major contributor to both chronic urticaria and recurrent angioedema. Treatment needs to focus on the use of long-acting, non-sedating, antihistamines. Corticosteroids may be used acutely but not long term.

2014;44(1):50-54

Available from: rcpe.ac.uk/sites/default/files/spickett.pdf