Medical Literature - 2019

Aygoren-Pursun E, Soteres DF, Nieto-Martinez SA, Christensen J, Jacobson KW, Moldovan D, Van Leerberghe A, Tang Y, Lu P, Vardi M, Schranz J, Martinez-Saguer I 8/2019 Pediatric Allergy and Immunology: Official Publication of the European Society of Pediatric Allergy and Immunology

BACKGROUND: Patients with hereditary angioedema with C1 inhibitor deficiency or dysfunction have burdensome recurrent angioedema attacks. The safety, efficacy, and health-related quality of life (HRQoL) outcomes of C1 inhibitor (C1-INH) prophylaxis (intravenously administered) in patients aged 6-11 years were investigated.

METHODS: Eligible patients were enrolled in a randomized, single-blind, crossover, phase 3 trial. After a 12-week baseline observation period (BOP), patients received 500 or 1000 U C1-INH, twice weekly, for 12 weeks before crossing over to the alternate dose for 12 weeks. The primary efficacy end-point was the monthly normalized number of angioedema attacks (NNA). HRQoL was assessed using the EuroQoL 5-dimensional descriptive system youth version and visual analog scale (EQ-VAS).

RESULTS: Twelve randomized patients had a median (range) age of 10.0 (7-11) years. Mean (SD) percentage reduction in monthly NNA from BOP was 71.1% (27.1%) with 500 U and 84.5% (20.0%) with 1000 U C1-INH. Mean (SD) within-patient difference (-0.4 [0.58]) for monthly NNA with both doses was significant (P = 0.035 [90% CI, -0.706 to -0.102]). Cumulative attack severity, cumulative daily severity, and number of acute attacks treated were reduced. No serious adverse events or discontinuations occurred. Mean EQ-VAS change from BOP to week 9 of treatment (500 U C1-INH, 10.4; 1000 U C1-INH, 21.6) was greater than the minimal important difference, indicating a meaningful HRQoL change.

CONCLUSIONS: C1-INH prophylaxis was effective, safe, and well tolerated in children aged 6-11 years experiencing recurrent angioedema attacks. A post hoc analysis indicated a meaningful improvement in HRQoL with C1-INH.

TRIAL REGISTRATION: ClinicalTrials.gov identifier NCT02052141. Copyright © 2019 The Authors. Pediatric Allergy and Immunology Published by John Wiley & Sons Ltd.

Available from: onlinelibrary.wiley.com/doi/full/10.1111/pai.13060

Hwang G, Johri A, Ng S, Craig T 8/2019 Immunotherapy

Hereditary angioedema with C1 esterase inhibitor deficiency is a rare disorder characterized by unpredictable swelling of the face, larynx and gastrointestinal tract. Kallikreins are serine proteases that cleave kininogens to produce bradykinin leading to inflammation. A new prophylactic drug is lanadelumab (DX-2930, SHP-643), a recombinant, fully human IgG1 monoclonal antibody kallikrein inhibitor. Pharmacokinetics show a half-life of 14 days with a dose-dependent effect. Completed trials for lanadelumab include two Phase III studies with updated efficacy in preventing angioedema in hereditary angioedema patients. Ongoing data show the safety of the targeted therapy along with less frequent administration requirements. Information on long-term safety is still needed, as well as, further studies on the correlation of subcutaneous administered dosing requirements and severity of side effects.

Available from: dx.doi.org/10.2217/imt-2018-0197

Miller RL, Shtessel M, Robinson LB, Banerji A 8/2019 Journal of Allergy & Clinical Immunology

Many notable advances in drug allergy, urticaria, angioedema, and anaphylaxis were reported in 2018. Broad-spectrum antibiotic use and, consequently, antibiotic resistance are widespread, and algorithms to clarify beta-lactam allergy and optimize antibiotic use were described. Meaningful data emerged on the pathogenesis of delayed drug hypersensitivity reactions. Progress not only in defining biomarkers but also in understanding the effect on quality of life and developing better treatments has been made for patients with chronic idiopathic urticaria. Patients with hereditary angioedema (HAE) have gained additional access to highly efficacious therapies, with associated improvements in quality of life, and some progress was made in our understanding of recurrent angioedema in patients with normal laboratory results. Guidelines have defined clear goals to help providers optimize therapies in patients with HAE. The epidemiology and triggers of anaphylaxis and the mechanisms underlying anaphylaxis were elucidated further. In summary, these disorders (and labels) cause substantial burdens for individual persons and even society. Fortunately, publications in 2018 have informed on advancements in diagnosis and management and have provided better understanding of mechanisms that potentially could yield new therapies. This progress should lead to better health outcomes and paths forward in patients with drug allergy, urticaria, HAE, and anaphylaxis. Copyright © 2019 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Available from: dx.doi.org/10.1016/j.jaci.2019.06.010

Chen ZL, Singh P, Wong J, Horn K, Strickland S, Norris EH 11/2019 Proceedings of the National Academy of Sciences of the United States of America

Bradykinin is a proinflammatory factor that mediates angioedema and inflammation in many diseases. It is a key player in some types of hereditary angioedema and is involved in septic shock, traumatic injury, Alzheimer’s disease (AD), and stroke, among others. Activation of the plasma contact system leads to elevated levels of plasma kallikrein, which cleaves high molecular weight kininogen (HK) to release bradykinin. Drug development for bradykinin-meditated pathologies has focused on designing inhibitors to the enzymes that cleave HK (to prevent bradykinin release) or antagonists of endothelial bradykinin receptors (to prevent downstream bradykinin action). Here we show a strategy to block bradykinin generation by using an HK antibody that binds to HK, preventing its cleavage and subsequent bradykinin release. We show that this antibody blocks dextran sodium sulfate-induced HK cleavage and bradykinin production. Moreover, while the pathogenic AD peptide beta-amyloid (Abeta)42 cleaves HK and induces a dramatic increase in bradykinin production, our HK antibody blocked these events from occurring. These results may provide strategies for developing treatments for bradykinin-driven pathologies. Copyright © 2019 the Author(s). Published by PNAS.

Available from: pnas.org/content/116/46/22921.long

Liu J, Qin J, Borodovsky A, Racie T, Castoreno A, Schlegel M, Maier MA, Zimmerman T, Fitzgerald K, Butler J, Akinc A 2/2019 RNA (New York, N.Y.)

Hereditary angioedema (HAE) is a genetic disorder mostly caused by mutations in the C1 esterase inhibitor gene (C1INH) that results in poor control of contact pathway activation and excess bradykinin generation. Bradykinin increases vascular permeability and is ultimately responsible for the episodes of swelling characteristic of HAE. We hypothesized that the use of RNA interference (RNAi) to reduce plasma Factor XII (FXII), which initiates the contact pathway signaling cascade, would reduce contact pathway activation and prevent excessive bradykinin generation. A subcutaneously administered GalNAc-conjugated small-interfering RNA (siRNA) targeting F12 mRNA (ALN-F12) was developed, and potency was evaluated in mice, rats, and cynomolgus monkeys. The effect of FXII reduction by ALN-F12 administration was evaluated in two different vascular leakage mouse models. An ex vivo assay was developed to evaluate the correlation between human plasma FXII levels and high-molecular weight kininogen (HK) cleavage. A single subcutaneous dose of ALN-F12 led to potent, dose-dependent reduction of plasma FXII in mice, rats, and NHP. In cynomolgus monkeys, a single subcutaneous dose of ALN-F12 at 3 mg/kg resulted in >85% reduction of plasma FXII. Administration of ALN-F12 resulted in dose-dependent reduction of vascular permeability in two different mouse models of bradykinin-driven vascular leakage, demonstrating that RNAi-mediated reduction of FXII can potentially mitigate excess bradykinin stimulation. Lastly, ex vivo human plasma HK cleavage assay indicated FXII-dependent bradykinin generation. Together, these data suggest that RNAi-mediated knockdown of FXII by ALN-F12 is a potentially promising approach for the prophylactic treatment of HAE. Copyright © 2019 Liu et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.

Available from: rnajournal.cshlp.org/content/early/2018/11/21/rna.068916.118

Bork K, Staubach-Renz P, Hardt J 3/2019 Orphanet Journal of Rare Diseases

BACKGROUND: Acquired angioedema due to C1-inhibitor (C1-INH) deficiency (AAE-C1-INH) is a serious condition that may result in life-threatening asphyxiation due to laryngeal edema. It is associated with malignant B-cell lymphoma and other disorders. The purpose of this study was to describe the characteristics and associated disorders of patients with AAE-C1-INH and assess the efficacy of plasma-derived C1-INH concentrate (pdC1-INH) in the treatment of AAE-C1-INH. Forty-four patients with AAE-C1-INH from the Angioedema Outpatient Service of Mainz were assessed for associated disorders. In 32 of these patients, the duration of swelling attacks was measured before and after treatment with pdC1-INH (Berinert R (CSL Behring, Marburg, Germany)). The time between injection and complete resolution of symptoms and treatment effectiveness was provided by the patients.

RESULTS: The following underlying disorders were present: monoclonal gammopathy of undetermined significance (47.7%), non-Hodgkin lymphoma (27.3%), anti-C1-INH autoantibodies alone (11.4%), and other conditions (4.5%). In 9.1% patients, no associated disorder could be found. AAE-C1-INH led to the detection of lymphoma in 75% of patients with the malignancy. Treatment with pdC1-INH shortened attacks by an average (SD) 54.4 (+/- 32.8) hours (P < 0.0001). The earlier the attack was treated, the shorter the time between injection and resolution of symptoms (P = 0.0149). A total of 3553 (97.7%) of the 3636 attacks were effectively treated with pdC1-INH as assessed by the patient. The mean (SD) dose per-attack was 787 (+/- 442) U. pdC1-INH was effective in 1246 (93.8%) of 1329 attacks in 8 patients with anti-C1-INH autoantibodies and in 344 (99.4%) of 346 attacks in 6 patients without autoantibodies. The average (SD) dose per effectively treated attack was 1238.4 (+/- 578.2) U in patients with anti-C1-INH autoantibodies and 510.2 (+/- 69.1) U in patients without autoantibodies.

CONCLUSIONS: pdC1-INH is highly effective in treating AAE-C1-INH patients and is also effective in the vast majority of attacks in patients with anti-C1-INH autoantibodies. It is fast-acting and reduces attack duration.

Available from: ojrd.biomedcentral.com/articles/10.1186/s13023-019-1043-3

Matsuura H, Osuka A, Hirose T, Ogura H, Ueyama M, Shimazu T 10/2019 Journal of Burn Care & Research

Hereditary angioedema has been attributed to an inherited deficiency of C1 esterase inhibitor that increases vascular permeability. The role of C1 esterase inhibitor in burn patients has not been described previously. In this study, we attempted to identify the relationship between serial changes of C1 esterase inhibitor activity and the clinical course in major burn patients. This study was a single-center, prospective, observational study. C1 esterase inhibitor activity values were serially examined in major burn patients admitted into the burn center from April 2014 to December 2016. Inclusion criteria were age >=16 years old and %TBSA burned >=20%. This study included 38 patients with major burn. C1 esterase inhibitor activity after burn dropped acutely on days 1 and 2 but increased immediately until days 3 to 5, after which it continued to gradually increase to above the reference value. C1 esterase inhibitor activity on admission showed significant inverse correlation with the volume of infusion per body weight required in the first 24 hours after injury and %TBSA burned (r = -0.405, P = 0.01; r = -0.375, P = 0.02, respectively). C1 esterase inhibitor activity on admission was significantly lower in the nonsurvivors than in the survivors during the 28-day evaluation period (59% vs 90%, P = 0.01). These findings suggest that C1 esterase inhibitor may play a critical role in regulating vascular permeability in the acute phase following the burn injury. Copyright © American Burn Association 2019. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Available from: dx.doi.org/10.1093/jbcr/irz109

Perego F, Wu MA, Valerieva A, Caccia S, Suffritti C, Zanichelli A, Bergamaschini L, Cicardi M 6/2019 Expert Opinion on Biological Therapy

INTRODUCTION: Hereditary angioedema due to C1-INH deficiency (C1-INH-HAE) is a rare disease with unpredictable, self-limiting and localized swelling episodes involving the cutaneous and subcutaneous tissues. In the last decade, the spectrum of the possibilities to control the disease has considerably changed with the development of biologic therapies making necessary a careful evaluation of the differences among current and emerging treatments to properly optimize the management of patients.

AREAS COVERED: This review serves to summarize the literature regarding the use of biologics for the treatment of C1-INH-HAE. Medications already available on the market and new drugs in different phases of development are addressed.

EXPERT OPINION: The advent of biologic therapies dramatically improved the lives of patients with C1-INH-HAE although further improvement is still needed. Whether this is cost/effective will be answered in the next years when we will see if these major advances will benefit the majority of the patients.

Available from: tandfonline.com/doi/abs/10.1080/14712598.2019.1595581?journalCode=iebt20

Obtulowicz K, Dyga W, Natorska J, Zabczyk M, Undas A 12/2019 Polish Archives Of Internal Medicine

Available from: dx.doi.org/10.20452/pamw.15096

Lumry WR, Martinez-Saguer I, Yang WH, Bernstein JA, Jacobs J, Moldovan D, Riedl MA, Johnston DT, Li HH, Tang Y, Schranz J, Lu P, Vardi M, Farkas H, SAHARA study group 5/2019 The Journal of Allergy & Clinical Immunology in Practice

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

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

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

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

Available from: dx.doi.org/10.1016/j.jaip.2019.01.021

Nebenfuhrer Z, Szabo E, Kajdacsi E, Kohalmi KV, Karadi I, Zsary A, Farkas H, Cervenak L 1/2019 Annals of Allergy, Asthma & Immunology: Official Publication of the American College of Allergy, Asthma, & Immunology

BACKGROUND: Hereditary angioedema with C1 inhibitor deficiency (C1-INH-HAE) is a rare, potentially life-threatening disorder characterized by recurrent edematous attacks. The edema formation is the consequence of interaction of bradykinin and various vasoactive peptides with endothelium. Besides these agents, danazol, a modified testosterone derivative used in these patients to prevent edematous attacks, can also affect the function of the endothelium, because it shifts the blood lipid profile to a pro-atherogenic phenotype.

OBJECTIVE: To assess the endothelial function in C1-INH-HAE patients and in healthy matched controls.

METHODS: To evaluate the endothelial function, we used the flow-mediated dilation method measured in the region of the brachial artery in 33 C1-INH-HAE patients and in 30 healthy matched controls. Laboratory measurements of standard biochemical parameters were performed on computerized laboratory analyzers.

RESULTS: No difference was found in endothelial function (reactive hyperemia, RH) between patients (median, 9.0; 25%-75% percentile, 6.3-12.9) and controls (median, 7.37; 25%-75% percentile, 4.52-9.93). Although we found elevated cardiovascular risk (high body mass index and low-density lipoprotein/high-density lipoprotein ratio) in danazol-treated C1-INH-HAE patients, RH values did not differ between danazol-treated and nontreated patients. Furthermore, risk factors correlated with the endothelial function only in healthy controls and patients not treated with danazol.

CONCLUSION: In summary, our results did not indicate any signs of endothelial dysfunction in C1-INH-HAE patients. Moreover, the normal endothelial function in danazol-treated patients with pro-atherogenic lipid profile suggests that elevated bradykinin level or other factor(s) involved in the pathogenesis of edematous attacks may have a protective role against endothelial dysfunction and atherosclerosis. Copyright © 2018. Published by Elsevier Inc.

Available from: annallergy.org/article/S1081-1206(18)31295-X/fulltext

Qiu T, Chiuchiolo MJ, Whaley AS, Russo AR, Sondhi D, Kaminsky SM, Crystal RG, Pagovich OE 6/2019 Allergy

BACKGROUND: Hereditary angioedema (HAE) is a life-threatening, autosomal dominant disorder characterized by unpredictable, episodic swelling of the face, upper airway, oropharynx, extremities, genitalia, and gastrointestinal tract. Almost all cases of HAE are caused by mutations in the SERPING1 gene resulting in a deficiency in functional plasma C1 esterase inhibitor (C1EI), a serine protease inhibitor that normally inhibits proteases in the contact, complement, and fibrinolytic systems. Current treatment of HAE includes long-term prophylaxis with attenuated androgens or human plasma-derived C1EI and management of acute attacks with human plasma-derived or recombinant C1EI, bradykinin, and kallikrein inhibitors, each of which requires repeated administration. As an approach to effectively treat HAE with a single treatment, we hypothesized that a one-time intravenous administration of an adeno-associated virus (AAV) gene transfer vector expressing the genetic sequence of the normal human C1 esterase inhibitor (AAVrh.10hC1EI) would provide sustained circulating C1EI levels sufficient to prevent angioedema episodes.

METHODS: To study the efficacy of AAVrh.10hC1EI, we used CRISPR/Cas9 technology to create a heterozygote C1EI-deficient mouse model (S63+/-) that shares characteristics associated with HAE in humans including decreased plasma C1EI and C4 levels. Phenotypically, these mice have increased vascular permeability of skin and internal organs.

RESULTS: Systemic administration of AAVrh.10hC1EI to the S63+/- mice resulted in sustained human C1EI activity levels above the predicted therapeutic levels and correction of the vascular leak in skin and internal organs.

CONCLUSION: A single treatment with AAVrh.10hC1EI has the potential to provide long-term protection from angioedema attacks in affected individuals. Copyright © 2018 EAACI and John Wiley and Sons A/S. Published by John Wiley and Sons Ltd.

Available from: ncbi.nlm.nih.gov/pmc/articles/PMC6752709

Pancholy N, Craig T 12/2019 Current Opinion in Pediatrics

PURPOSE OF REVIEW: Hereditary angioedema (HAE) most often presents in the first two decades of life. Despite these patients often see multiple doctors and go many years before confirmation of the diagnosis. the impact on quality of life, productivity and risk of anxiety, depression, and posttraumatic stress emphasizes the need for early diagnosis and appropriate treatment.

RECENT FINDINGS: Over the past decade, therapy in the USA has emerged from fresh-frozen plasma and androgens to more than seven medications that are specific for bradykinin-induced disease. During the same time, treatment has evolved from intravenous to subcutaneous and the future will be a focus on oral therapy.

SUMMARY: Much optimism exists that patients with HAE will live a life with minimal disease and impact on their quality of life making it even more important to diagnose children at an early age.

Available from: journals.lww.com/co-pediatrics/Abstract/2019/12000/Hereditary_angioedema_in_children__a_review_and.26.aspx

Javaud N, Altar A, Fain O, Reuter PG, Desmaizieres M, Petrovic T, Ghazali A, Durand-Zaleski I, Bouillet L, Vicaut E, Launay D, Martin L, Floccard B, Gompel A, Sobel A, Boccon-Gibod I, Kanny G, Lapostolle F, Adnet F 9/2019 European Journal of Internal Medicine

OBJECTIVE: Hereditary angioedema (HAE) is a rare autosomal dominant disease characterized by recurrent, unpredictable, potentially life-threatening swelling. Objective is to assess the management of the acute HAE attacks in the real life setting through a call center in France.

METHODS: A pre-specified ancillary study of SOS-HAE, a cluster-randomized prospective multicenter trial, was conducted. HAE patients were recruited from 8 participating reference centers. The outcome of interest was the rate of hospitalization.

RESULTS: onerhundred patients were included. The median (quartile) age was 38 (29-53) years, and 66 (66%) were female. Eighty (80%) patients had HAE type I, 8 (8%) had HAE type II and 12 (12%) patients had FXII-HAE. Fifty-one (51%) patients had experienced at least one time the call center during the follow-up. Nine over 166 (5%) attacks for 9 different patients resulted in hospital admission to the hospital (in the short-stay unit, ie, <24h) during the follow-up period. During 2years, there were 166 calls to call center for 166 attacks. All attacks were treated at home after call center contact.

CONCLUSIONS: Use of emergency departments and hospitalizations are reduced by the use of a coordinated national call center in HAE after therapeutic education program that promoted self-administration of specific treatment and use of call to call center.

TRIAL REGISTRATION: clinicalTrials.gov identifier: NCT01679912. Copyright © 2019 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

Available from: sciencedirect.com/science/article/abs/pii/S0953620519301529

Longhurst HJ, Bork K 7/2019 British Journal of Hospital Medicine

Hereditary angioedema is a rare genetic disorder caused by deficiency of C1 esterase inhibitor (C1-INH) and characterized by recurrent episodes of severe swelling that affect the limbs, face, intestinal tract and airway. Since laryngeal oedema can be life-threatening as a result of asphyxiation, correct diagnosis and management of hereditary angioedema is vital. Hereditary angioedema attacks are mediated by bradykinin, the production of which is regulated by C1-INH. Hereditary angioedema therapy relies on treatment of acute attacks, and short- and long-term prophylaxis. Acute treatment options include C1-INH concentrate, icatibant and ecallantide. Self-administration of treatment is recommended and is associated with increased quality of life of patients with hereditary angioedema. Advances in diagnosis and management have improved the outcomes and quality of life of patients with hereditary angioedema.

Available from: magonlinelibrary.com/doi/full/10.12968/hmed.2019.80.7.391

Cosme J, Spinola A, Ferreira MB, Barbosa MP 11/2019 Acta Medica Portuguesa

INTRODUCTION: Hospitalizations due to angioedema are important especially in debilitating or life-threatening situations. The aim of this study was to evaluate the frequency and etiology of angioedema without urticaria in hospital admissions.

MATERIAL AND METHODS: The admissions between 2009 and 2013 in Centro Hospitalar Lisboa Norte with a diagnosis grouped under the ICD9 codes of angioedema were retrospectively analysed. The episodes of angioedema with urticaria were excluded. The admissions were categorized into 2 groups: A – hospitalizations motivated by the angioedema; B – hospitalizations in which the angioedema was an incidental finding.

RESULTS: There were 169 hospitalizations (52% females, 96% adults, mean age 52 +/- 20.8 years), distributed by 23 hospital departments, 51% in the Immunoallergology department. The mean annual angioedema admission rate was 72/100 000. In 68% of the cases, angioedema was the cause for the admission; in 32% an incidental finding. In 38% there was upper airway involvement. The etiologies were: hereditary angioedema in 24%, angiotensin converting enzyme inhibitor induced angioedema in 31%, idiopathic angioedema in 21%, thrombolysis induced angioedema in 13%, nonsteroidal anti-inflammatory drug-induced angioedema in 5%.

DISCUSSION: The main etiology was angiotensin converting enzyme inhibitor angioedema, followed by hereditary angioedema and thrombolysis induced angioedema, and these findings concur with the international literature.

CONCLUSION: The mean annual angioedema admission rate was 72/100 000 and there was airway involvement in 38% of hospitalizations.

Available from: actamedicaportuguesa.com/revista/index.php/amp/article/view/11893

Guo C, Greenberger PA 11/2019 Allergy & Asthma Proceedings

Idiopathic anaphylaxis (IA) is defined as anaphylaxis without any identifiable precipitating agent or event. The clinical manifestations of IA are the same as allergen-associated (immunologic) anaphylaxis and include urticaria, angioedema, hypotension, tachycardia, wheezing, stridor, pruritus, nausea, vomiting, flushing, diarrhea, dysphagia, light-headedness, and loss of consciousness. Patients usually tend to have the same manifestations on repeated episodes. IA is a prednisone-responsive disease that is ultimately a diagnosis of exclusion. Approximately 40% of patients are atopic. Serum tryptase (or urine histamine or its metabolite) will be elevated acutely, but, if elevated in the absence of anaphylaxis, should suggest alternative diagnoses, including indolent systemic mastocytosis. A focused history, examination, and follow-up will dictate whether a patient’s symptoms may be attributable to disorders that mimic anaphylaxis, such as indolent systemic mastocytosis, carcinoid syndrome, pheochromocytoma, hereditary angioedema or acquired C1 esterase inhibitor deficiency, or panic attacks. The presence of urticaria may help limit the differential diagnosis because urticaria does not usually accompany any of the above-mentioned disorders, except for indolent systemic mastocytosis. IA is classified according to the symptoms as well as the frequency of attacks. Patients who experience six or more episodes in a year, or two or more episodes in 2 months are classified as having IA-frequent (IA-F). Patients who experience fewer episodes are classified as having IA-infrequent (IA-I). This distinction is important because patients with IA-F will initially require prednisone as disease-modifying therapy, whereas most patients who with IA-I will not require prednisone. Patients with IA must carry and know when and how to self-administer epinephrine.

Available from: dx.doi.org/10.2500/aap.2019.40.4271

Bernstein JA, Li HH, Craig TJ, Manning ME, Lawo JP, Machnig T, Krishnarajah G, Fridman M 3/2019 Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology

INTRODUCTION: For prophylaxis of hereditary angioedema (HAE) attacks, replacement therapy with human C1-inhibitor (C1-INH) treatment is approved and available as intravenous [C1-INH(IV)] (Cinryze R) and subcutaneous [C1-INH(SC)] HAEGARDA R preparations. In the absence of a head-to-head comparative study of the two treatment modalities, an indirect comparison of data from 2 independent but similar clinical trials was undertaken.

METHODS: Two similar randomized, double-blind, placebo-controlled, crossover studies were identified which evaluated either C1-INH(SC) (COMPACT; NCT01912456; 16 weeks) or C1-INH(IV) (CHANGE; NCT01005888; 14 weeks) vs. placebo (on-demand treatment only) for routine prevention of HAE attacks. Individual patient data from each trial were used to conduct an indirect comparison of treatment effects. Attack reductions (absolute and percent of mean/median number of monthly HAE attacks reduction over placebo) were compared between the two C1-INH formulations at approved/recommended doses: C1-INH(SC) 60 IU/kg twice weekly (n = 45) and 1000 U of C1-INH(IV) twice weekly (n = 22). Point estimates were adjusted using mixed and quantile regression models that controlled for study design.

RESULTS: The absolute mean monthly numbers of HAE attack reductions were 3.6 (95% CI 2.9, 4.2) for C1-INH(SC) 60 IU/kg vs. placebo and 2.3 (1.4, 3.3) for C1-INH(IV) vs. placebo; between-product difference, 1.3 (0.1, 2.4; P = 0.034). The mean percent reduction in monthly attack rate was significantly greater with C1-INH(SC) as compared with C1-INH(IV) (84% vs. 51%; P < 0.001). The percentages of subjects experiencing >= 50%, >= 70%, and >= 90% reductions in monthly HAE attack rates versus placebo were significantly higher with C1-INH(SC) 60 IU/kg as compared to C1-INH(IV) 1000 U (>= 50% reduction: 91% vs. 50%, odds ratio [OR] = 10.33, P = 0.003; >= 70% reduction: 84% vs. 46%, OR = 6.19, P = 0.005; >= 90% reduction: 57% vs. 18%, OR = 6.04, P = 0.007).

CONCLUSION: Within the limitations of an indirect study comparison, this analysis suggests greater attack reduction with twice-weekly C1-INH(SC) 60 IU/kg as compared to twice-weekly C1-INH(IV) 1000 U for the routine prevention of HAE attacks.

Available from: ncbi.nlm.nih.gov/pmc/articles/PMC6407188

Valerieva A, Senter R, Wu MA, Zanichelli A, Cicardi M 12/2019 Expert Review of Clinical Immunology

INTRODUCTION: Hereditary angioedema (HAE) with C1 esterase inhibitor deficiency (C1-INH-HAE) is a rare disease that manifests with cutaneous and/or submucosal swellings due to uncontrolled activation of the contact/kinin system. Attacks recur with unpredictable frequency and severity, laryngeal edema is potentially lethal, and the disease burden may severely disrupt patients’ lives.

AREAS COVERED: This review provides an overview of lanadelumab, a human monoclonal antibody targeted against plasma kallikrein that was recently approved for prevention of symptoms in C1-INH-HAE.

EXPERT OPINION: The phase III HELP Study demonstrated the efficacy of lanadelumab in reducing HAE attacks. These positive results are being further confirmed in the open-label extension study. This agent addresses some of the limitations of existing prophylactic options as tolerability issues, the need for intravenous administration and frequent dosing. Therefore, lanadelumab can profoundly improve the quality of life of patients with C1-INH-HAE.

Available from: dx.doi.org/10.1080/1744666X.2020.1693261

Busse PJ, Farkas H, Banerji A, Lumry WR, Longhurst HJ, Sexton DJ, Riedl MA 2/2019 BioDrugs: Clinical Immunotherapeutics, Biopharmaceuticals and Gene Therapy

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

Available from: link.springer.com/article/10.1007/s40259-018-0325-y

Wu MA 12/2019 Expert Opinion on Biological Therapy

INTRODUCTION: Hereditary angioedema due to C1 inhibitor deficiency (C1-INH-HAE) is a rare yet still probably underdiagnosed clinical condition. Recurrent episodes of subcutaneous and sub-mucosal swelling may involve the skin, the gastrointestinal tract or even the upper airways, exposing the patients to the risk of death. With the aim of improving patients’ quality of life, the therapeutic scenario has expanded over the years.

AREAS COVERED: The focus of the present review is lanadelumab, a fully human, kappa-light-chain, monoclonal immunoglobulin G1 against plasma kallikrein, currently approved for long-term prophylaxis of C1-INH-HAE attacks in the USA and Canada and designated as an orphan drug by the European Medicines Agency.

EXPERT OPINION: Lanadelumab is able to inhibit plasma kallikrein with high selectivity and affinity. The subsequent phases of drug development and the ongoing open-label trial have proven its safety and efficacy. It overcomes some of the limitations of other drugs available for long-term prophylaxis, given the easy route of administration, the simple administration schedule and the possibility to tailor the treatment to each patient. Further studies are needed to test its efficacy also in other types of angioedema for which a central role of plasma kallikrein is envisaged.

Available from: dx.doi.org/10.1080/14712598.2019.1685490

Bova M, Valerieva A, Wu MA, Senter R, Perego F 11/2019 Drug Design, Development and Therapy

Despite the efficacy of the on-demand treatment for the control of acute attacks of Hereditary Angioedema due to C1-Inhibitor Deficiency (C1-INH-HAE), the number and severity of attacks and the impairment in the quality of life of the affected patients have led to the development of a new monoclonal antibody, lanadelumab, directly addressed to the blockage of bradykinin, the principal mediator of vasodilation during angioedema attacks. It is indicated for the prophylactic treatment, it is easy to administer, highly effective and with known limited side effects. The current review summarizes the development of the drug, its clinical background and its perspectives. Copyright © 2019 Bova et al.

Available from: dovepress.com/lanadelumab-injection-treatment-for-the-prevention-of-hereditary-angio-peer-reviewed-fulltext-article-DDDT

Wedi B 7/2019 Drugs of Today

Lanadelumab is a human monoclonal antibody against plasma kallikrein indicated for prevention of attacks of hereditary angioedema (HAE). HAE is caused by SERPING1 gene mutations resulting in decreased or dysfunctional plasma protease C1 inhibitor (C1-INH) leading to a loss of inhibition of plasma kallikrein activity with subsequent cleavage of high-molecular weight kininogen and release of bradykinin. There is a clear need for a non-plasma-derived, safe, effective and convenient prophylaxis of HAE attacks to reduce patients’ daily burden of disease and disability. The percentage of patients who were attack-free for the last 16 weeks of a controlled study was 77% in the group receiving 300 mg lanadelumab every 2 weeks, compared with 3% with placebo. The most common side effects were mild injection-site reactions. Lanadelumab has the potential to change the approach from on-demand treatment to prophylaxis in HAE. Future studies will have to confirm long-term safety and efficacy of prophylactic long-term inhibition of plasma kallikrein. Copyright 2019 Clarivate Analytics.

Available from: journals.prous.com/journals/servlet/xmlxsl/pk_journals.xml_summaryn_pr?p_JournalId=4&p_RefId=2985293

Syed YY 11/2019 Drugs

Lanadelumab (Takhzyro TM), a first-in-class fully human monoclonal antibody against plasma kallikrein, has been approved in several countries, including Australia, Canada, those of the EU, Switzerland and the USA, for the prevention of hereditary angioedema (HAE) attacks in patients aged >=12 years. Subcutaneous lanadelumab significantly reduced HAE attack rates relative to placebo in the pivotal HELP trial. The clinical benefits of lanadelumab were seen regardless of prior long-term prophylaxis use, baseline disease activity, sex or body mass index. Lanadelumab therapy was associated with clinically meaningful improvements in HAE-specific quality of life. Lanadelumab was generally well tolerated. The most common adverse events with lanadelumab were injection-site reactions, which were generally mild and transient. Lanadelumab has a low potential for immunogenicity. It offers the convenience of self-administered subcutaneous injections once every 2 weeks (starting dosage). Currently available data indicate that lanadelumab is an effective, well-tolerated, novel prophylactic option for patients with HAE aged >=12 years.

Available from: dx.doi.org/10.1007/s40265-019-01206-w

Craig T, Zuraw B, Longhurst H, Cicardi M, Bork K, Grattan C, Katelaris C, Sussman G, Keith PK, Yang W, Hebert J, Hanzlikova J, Staubach-Renz P, Martinez-Saguer I, Magerl M, Aygoren-Pursun E, Farkas H, Reshef A, Kivity S, Neri S, Crisan I, Caballero T, Baeza ML, Hernandez MD, Li H, Lumry W, Bernstein JA, Hussain I, Anderson J, Schwartz LB, Jacobs J, Manning M, Levy D, Riedl M, Christiansen S, Feuersenger H, Pragst I, Mycroft S, Pawaskar D, Jacobs I, COMPACT Investigators 7/2019 The Journal of Allergy & Clinical Immunology in Practice

BACKGROUND: For the prevention of attacks of hereditary angioedema (HAE), the efficacy and safety of subcutaneous human C1-esterase inhibitor (C1-INH[SC]; HAEGARDA, CSL Behring) was established in the 16-week Clinical Study for Optimal Management of Preventing Angioedema with Low-Volume Subcutaneous C1-Inhibitor Replacement Therapy (COMPACT).

OBJECTIVE: To assess the long-term safety, occurrence of angioedema attacks, and use of rescue medication with C1-INH(SC).

METHODS: Open-label, randomized, parallel-arm extension of COMPACT across 11 countries. Patients with frequent angioedema attacks, either study treatment-naive or who had completed COMPACT, were randomly assigned (1:1) to 40 IU/kg or 60 IU/kg C1-INH(SC) twice per week, with conditional uptitration to optimize prophylaxis (ClinicalTrials.gov registration no. NCT02316353).

RESULTS: A total of 126 patients with a monthly attack rate of 4.3 in 3 months before entry in COMPACT were enrolled and treated for a mean of 1.5 years; 44 patients (34.9%) had more than 2 years of exposure. Mean steady-state C1-INH functional activity increased to 66.6% with 60 IU/kg. Incidence of adverse events was low and similar in both dose groups (11.3 and 8.5 events per patient-year for 40 IU/kg and 60 IU/kg, respectively). For 40 IU/kg and 60 IU/kg, median annualized attack rates were 1.3 and 1.0, respectively, and median rescue medication use was 0.2 and 0.0 times per year, respectively. Of 23 patients receiving 60 IU/kg for more than 2 years, 19 (83%) were attack-free during months 25 to 30 of treatment.

CONCLUSIONS: In patients with frequent HAE attacks, long-term replacement therapy with C1-INH(SC) is safe and exhibits a substantial and sustained prophylactic effect, with the vast majority of patients becoming free from debilitating disease symptoms. Copyright © 2019 The Authors. Published by Elsevier Inc. All rights reserved.

Available from: dx.doi.org/10.1016/j.jaip.2019.01.054

Maurer M, Bork K, Martinez-Saguer I, Aygoren-Pursun E, Botha J, Andresen I, Magerl M 1/2019 Journal of the European Academy of Dermatology and Venereology: JEADV

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. Copyright © 2018 The Authors. Journal of the European Academy of Dermatology and Venereology published by John Wiley & Sons Ltd on behalf of European Academy of Dermatology and Venereology.

Available from: onlinelibrary.wiley.com/doi/full/10.1111/jdv.15232

Goubran H, Goubran M, Seghatchian J, Burnouf T 4/2019 Transfusion and Apheresis science: Official Journal of the World Apheresis Association: Official Journal of the European Society for Haemapheresis

Since the first successful transfusion in 1818, Transfusion Medicine has evolved significantly. The advent of plasma fractionation and availability of recombinant products allowed for precision replacement therapy to treat many hematological conditions, such as hemophilia, thrombotic thrombocytopenic purpura, and hereditary angioedema. A deeper understanding of the pathophysiology underlying those conditions along with the development of safer monoclonal and bispecific antibodies is now offering safe and effective alternatives to the simple conventional approach of replacing a missing plasma protein. Many biologicals are already in wide clinical use in areas such as rheumatology, gastroenterology, and medical oncology. The introduction of novel therapeutic antibodies within the realm of Transfusion Medicine will likely reshape the field and challenge the role of local blood establishments as the gate-keepers of such therapies. Copyright © 2019 Elsevier Ltd. All rights reserved.

Available from: trasci.com/article/S1473-0502(19)30022-9/fulltext

Komaravolu Y, Dama VR, Maringanti TC 2/2019 Amino Acids

Qualitative and quantitative determination of amino acid composition using amino acid analysis (AAA) is an important quality attribute and considered an identity of therapeutic peptide drugs by the regulatory agencies. Although huge literature is available on pre- and post- column derivatization AAA methods, arriving at an appropriate hydrolysis protocol coupled with adequate separation of the derivatized/underivatized amino acids is always challenging. Towards achieving a facile and comprehensive protocol for AAA, the present work is geared towards developing a deeper understanding of the extent of hydrolysis of peptide, and the nature and stability of amino acids present in the peptide backbone. This defines the suitability of the method in meeting the end goals and the regulatory requirement. Analysis of historical data generated during the method optimization of AAA for icatibant acetate (ICT) using head space oven hydrolysis (HSOH) and microwave-assisted hydrolysis (MAH) methods helped in arriving at fast (< 1 h) and efficient hydrolysis (0.9-1.1 of theoretical residue) conditions. Better separations for the natural and unnatural amino acids were achieved using 3.45 <= pH <= 10.85, and a column oven gradient program. This approach was useful in meeting the method quality attributes [resolution (Rs) > 2.0; plate count (N) > 5600; and USP tailing factor < 1.2] with a target analytical method profile of relative amino acid mole ratios (RAAMR) in the range of 0.9-1.1 for Ser, Oic, Tic, Hyp, Ala (Thi), Gly and Pro, and between 2.7 and 3.3 for Arg. The developed method was validated as per the ICH guidelines and is precise, accurate, linear and robust.

Available from: link.springer.com/article/10.1007%2Fs00726-018-2665-9

Hwang JR, Hwang G, Johri A, Craig T 12/2019 Immunotherapy

Hereditary angioedema (HAE) is rare disorder caused by a SERPING1 gene mutation that triggers severe swelling of the skin and upper airway. Treatment options for HAE with deficient and dysfunctional C1-inhibitor are expanding to include small-molecule drugs that inhibit protein interactions in the kallikrein-kinin system. Discovered by BioCryst Pharmaceuticals, BCX7353 is a synthetic, once-daily, small molecule drug that can be taken as an oral capsule to treat HAE attacks and for prophylaxis. This article will summarize recent and current BCX7353 clinical trials. Overall, results indicate BCX7353 is a promising form of therapy with a rapid 1 h onset of action, long duration of action, and acceptable tolerance.

Available from: dx.doi.org/10.2217/imt-2019-0128

Grumach AS, Longhurst HJ, Aberer W, Bouillet L, Caballero T, Bygum A, Zanichelli A, Botha J, Andresen I, Maurer M, Icatibant Outcome Survey investigators 3/2019 The Journal of Allergy & Clinical Immunology in Practice

Available from: dx.doi.org/10.1016/j.jaip.2018.07.047

Reshef A, Grivcheva-Panovska V, Kessel A, Kivity S, Klimaszewska-Rembiasz M, Moldovan D, Farkas H, Gutova V, Fritz S, Relan A, Giannetti B, Magerl M 8/2019 Pediatric Allergy and Immunology: Official Publication of the European Society of Pediatric Allergy and Immunology

BACKGROUND: Attacks of hereditary angioedema (HAE) due to C1 esterase inhibitor deficiency (C1-INH-HAE) usually begin during childhood or adolescence. However, limited data are available regarding indications and modalities of treatment of children. This study evaluated recombinant human C1-INH (rhC1-INH) for HAE attacks in children.

METHODS: This open-label, phase 2 study included children aged 2-13 years with C1-INH-HAE. Eligible HAE attacks were treated intravenously with rhC1-INH 50 IU/kg body weight (maximum, 4200 IU). The primary end-point was time to beginning of symptom relief (TOSR; >=20 mm decrease from baseline in visual analog scale [VAS] score, persisting for two consecutive assessments); secondary end-point was time to minimal symptoms (TTMS; <20 mm VAS score for all anatomic locations).

RESULTS: Twenty children (aged 5-14 years; 73 HAE attacks) were treated with rhC1-INH. Seventy (95.9%) of the attacks were treated with a single dose of rhC1-INH. Seven (35.0%) children were treated for four or more attacks. Overall, median TOSR was 60.0 minutes (95% confidence interval [CI], 60.0-65.0); data were consistent across attacks. Median TTMS was 122.5 minutes (95% CI, 120.0-126.0); data were consistent across attacks. No children withdrew from the study due to adverse events. No treatment-related serious adverse events or hypersensitivity reactions were reported; no neutralizing antibodies were detected.

CONCLUSIONS: Recombinant human C1-INH was efficacious, safe, and well tolerated in children. Data support use of the same dosing regimen for HAE attacks in children (50 IU/kg; up to 4200 IU, followed by an additional dose, if needed) as is currently recommended for adolescents and adults. Copyright © 2019 The Authors. Pediatric Allergy and Immunology Published by John Wiley & Sons Ltd.

Available from: onlinelibrary.wiley.com/doi/full/10.1111/pai.13065

Liu S, Wang X, Xu Y, Xu Q, Zhi Y 9/2019 Allergy & Asthma Proceedings

BACKGROUND: Hereditary angioedema (HAE) is still underdiagnosed or diagnosed after a serious delay. This study aimed to evaluate the diagnostic delay (DD) and misdiagnosis of HAE, and to explore the risk factors associated with a longer DD.

METHODS: An Internet-based survey was sent to 129 patients with type 1 and 2 HAE who presented to the Allergy Department, Peking Union Medical College Hospital between 1983 and 2017; 107 patients (82.9%) responded, among whom, a total of 96 patients provided complete information about medical visits. DD was divided into two subperiods according to the lower quartile, i.e., DD <= 6 years and DD > 6 years.

RESULTS: The median DD of all 96 patients with HAE was 11.04 years (interquartile range [IQR], 6.06-18.27 years). A significant difference (p < 0.001) in the median DD was found between different decades of onset, i.e., before 1999 (19.75 years [IQR, 13.58-29.50 years]), between 2000 and 2009 (8.67 years [IQR, 5.67-11.04 years]), and between 2010 and 2017 (3.79 years [IQR, 2.29-5.71 years]). Patients with a previous misdiagnosis experienced a longer median delay to complement 1 inhibitor HAE diagnosis (13.17 years [IQR, 7.40-20.50 years]) compared with patients without a previous misdiagnosis (median 6.96 years [IQR, 2.83-10.65 years]; p <= 0.001). According to the logistic regression analysis, a younger age of onset and earlier decade of onset were significant predictors of a DD of >6 years. The most frequently visited departments and most frequently misdiagnosed diseases were summarized.

CONCLUSION: The median DD of patients with HAE was 11.04 years (IQR, 6.06-18.27 years). A younger age of onset and earlier decade of onset were predictors of a DD of >6 years. Seventy-five percent of the patients reported receiving more than one previous misdiagnosis. The patients with a previous misdiagnosis had longer DDs compared with patients without a misdiagnosis.

Available from: dx.doi.org/10.2500/aap.2019.40.4234

Li HH, Zuraw B, Longhurst HJ, Cicardi M, Bork K, Baker J, Lumry W, Bernstein J, Manning M, Levy D, Riedl MA, Feuersenger H, Prusty S, Pragst I, Machnig T, Craig T, COMPACT Investigators 8/2019 Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology

BACKGROUND: Hereditary angioedema (HAE) is a debilitating disorder resulting from C1-esterase inhibitor (C1-INH) deficiency. In the COMPACT phase 3 study the prophylactic use of a subcutaneous C1 inhibitor (C1-INH [SC], HAEGARDA R, CSL Behring) twice weekly significantly reduced the frequency of acute edema attacks. Analysis of treatment effects by subgroups, onset of effect, and other exploratory analysis have not been reported.

METHODS: This is a post hoc exploratory analysis on data from the randomized, placebo-controlled COMPACT study. 90 patients with C1-INH-HAE were randomized to 1 of 4 treatment sequences: C1-INH (SC) 40 or 60 IU/kg of body weight twice weekly for 16 weeks, preceded or followed by a placebo period. The pre-specified primary efficacy endpoint was the time-normalized number of HAE attacks, and pre-specified secondary efficacy endpoints were the percentage of patients with a certain treatment response (>= 50% reduction on C1-INH (SC) versus placebo in the time-normalized number of attacks) and the time-normalized number of use of rescue medication. Pre-specified exploratory endpoints included severity of attacks, alone and combined with rescue medication use. Post hoc analyses included exploration of onset of effect and clinical assessment of patients with < 50% of response.

RESULTS: Subgroup findings by various patient characteristics showed a consistent preventive effect of C1-INH (SC). In a post hoc analysis of attacks, the onset of the preventive effect within the first 2 weeks after treatment initiation in COMPACT showed that 10/43 patients (23%) experienced attacks of any severity with 60 IU/kg versus 34/42 patients (81%) with placebo. The need for rescue medication was tenfold lower with 60 IU/kg (35 treated attacks) versus placebo (358 treated attacks). A qualitative analysis of the 4 patients treated with 60 IU/kg and with < 50% reduction of attacks demonstrated a reduction in severity of attacks, rescue medication use, and symptom days which was considered a clinically meaningful treatment effect.

CONCLUSIONS: C1-INH (SC) prophylaxis demonstrated a preventive treatment effect with evidence of benefit within 2 weeks. A consistent treatment effect at recommended C1-INH (SC) dosing was evident in all subgroups of patients with type I/II HAE and by various measures of disease and treatment burden. Trial registration EU Clinical Trials Register, 2013-000916-10, Registered 10 December 2013, clinicaltrialsregister.eu/ctr-search/trial/2013-000916-10; ClinicalTrials.gov Register, NCT01912456, Registered 31 July 2013, clinicaltrials.gov/ct2/show/NCT01912456.

Available from: ncbi.nlm.nih.gov/pmc/articles/PMC6714075

Agboola F, Lubinga S, Carlson J, Lin GA, Dreitlein WB, Pearson SD. 2/2019 Journal of Managed Care & Specialty Pharmacy

DISCLOSURES: Funding for this summary was contributed by the Laura and John Arnold Foundation, Blue Shield of California, and California Health Care Foundation to the Institute for Clinical and Economic Review (ICER), an independent organization that evaluates the evidence on the value of health care interventions. ICER’s annual policy summit is supported by dues from Aetna, AHIP Anthem, Blue Shield of California, CVS Caremark, Express Scripts, Harvard Pilgrim Health Care, Cambia Health Solutions, United Healthcare, Kaiser Permanente, Premera Blue Cross, AstraZeneca, Genentech, GlaxoSmithKline, Johnson & Johnson, Merck, National Pharmaceutical Council, Prime Therapeutics, Sanofi, Spark Therapeutics, Health Care Service Corporation, Editas, Alnylam, Regeneron, Mallinkrodt, Biogen, HealthPartners, and Novartis. Agboola, Dreitlein, and Pearson are ICER employees. Lin reports personal fees from ICER, during the conduct of this study, and grants from the National Institutes of Health and the California Department of Insurance, outside the submitted work. Carlson and Lubinga report grants from ICER, during the conduct of this study.

Available from: jmcp.org/doi/10.18553/jmcp.2019.25.2.143

Betschel S, Badiou J, Binkley K, Borici-Mazi R, Hebert J, Kanani A, Keith P, Lacuesta G, Waserman S, Yang B, Aygoren-Pursun E, Bernstein J, Bork K, Caballero T, Cicardi M, Craig T, Farkas H, Grumach A, Katelaris C, Longhurst H, Riedl M, Zuraw B, Berger M, Boursiquot JN, Boysen H, Castaldo A, Chapdelaine H, Connors L, Fu L, Goodyear D, Haynes A, Kamra P, Kim H, Lang-Robertson K, Leith E, McCusker C, Moote B, O'Keefe A, Othman I, Poon MC, Ritchie B, St-Pierre C, Stark D, Tsai E 11/2019 Allergy, asthma, and clinical immunology : official journal of the Canadian Society of Allergy and Clinical Immunology

This is an update to the 2014 Canadian Hereditary Angioedema Guideline with an expanded scope to include the management of hereditary angioedema (HAE) patients worldwide. It is a collaboration of Canadian and international HAE experts and patient groups led by the Canadian Hereditary Angioedema Network. The objective of this guideline is to provide evidence-based recommendations, using the GRADE system, for the management of patients with HAE. This includes the treatment of attacks, short-term prophylaxis, long-term prophylaxis, and recommendations for self-administration, individualized therapy, quality of life, and comprehensive care. New to the 2019 version of this guideline are sections covering the diagnosis and recommended therapies for acute treatment in HAE patients with normal C1-INH, as well as sections on pregnant and paediatric patients, patient associations and an HAE registry. Hereditary angioedema results in random and often unpredictable attacks of painful swelling typically affecting the extremities, bowel mucosa, genitals, face and upper airway. Attacks are associated with significant functional impairment, decreased health-related quality of life, and mortality in the case of laryngeal attacks. Caring for patients with HAE can be challenging due to the complexity of this disease. The care of patients with HAE in Canada, as in many countries, continues to be neither optimal nor uniform. It lags behind some other countries where there are more organized models for HAE management, and greater availability of additional licensed therapeutic options. It is anticipated that providing this guideline to caregivers, policy makers, patients, and advocates will not only optimize the management of HAE, but also promote the importance of individualized care. The primary target users of this guideline are healthcare providers who are managing patients with HAE. Other healthcare providers who may use this guideline are emergency and intensive care physicians, primary care physicians, gastroenterologists, dentists, otolaryngologists, paediatricians, and gynaecologists who will encounter patients with HAE and need to be aware of this condition. Hospital administrators, insurers and policy makers may also find this guideline helpful. Copyright © The Author(s) 2019.

Available from: ncbi.nlm.nih.gov/pmc/articles/PMC6878678