Faculty Bibliography

Scientific and clinical progress together with the development of effective novel therapeutic options has engendered multiple important changes in the diagnosis and management of hereditary angioedema (HAE). We now update and extend the 2013 United States Hereditary Angioedema Association Medical Advisory Board guidelines for the treatment and management of HAE. The guidelines are based on a comprehensive literature review with recommendations indicating both the strength of our recommendation and the quality of the underlying evidence. Guidelines are provided regarding the classification, diagnosis, on-demand treatment, prophylactic treatment, special considerations for women and children, development of a comprehensive management and monitoring plan, and assessment of burden of illness for both HAE due to C1 inhibitor deficiency and HAE with normal C1 inhibitor. Advances in HAE treatment now allow the development of management plans that can help many patients with HAE lead a normal life. Achieving this goal requires that physicians be familiar with the diagnostic and therapeutic transformations that have occurred in recent years.

BACKGROUND:Hereditary angioedema (HAE) symptoms may be triggered by dental procedures, thereby complicating dental care in individuals affected by the condition. OBJECTIVE:This study investigated the self-perceived dental care needs, perceived susceptibility to acute angioedema (AE) attacks after dental procedures, and dental care behavior of patients with HAE. METHODS:tests, logistic regression, and classification trees. RESULTS:A total of 46.4% of HAE versus 55.5% of control patients had dental visits within 6 months (P = .04). Dental insurance was a barrier to seeking routine dental visits among both groups. However, significantly fewer patients with HAE had routine dental visits within 6 months despite having dental insurance compared with control patients (48% vs 60%, P = .01). Within the HAE group, a significantly greater number of patients with dental visits at intervals greater than 6 months had a history of recurrent postprocedural AE attacks (odds ratio [OR]: 3.9 [1.7, 8.8], P = .0005) and used antibacterial toothpaste more frequently than those without recurrent AE attacks (OR: 4.7 [1.5, 15.4], P = .005). CONCLUSIONS:These data support the hypothesis that patients with HAE who are predisposed to having AE episodes in response to medical or physical trauma visit the dentist less and engage in specific oral hygiene practices more frequently than matched control patients and patients with HAE who reported that they were less likely to swell after a dental procedure.

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

Hereditary angioedema (HAE) is a rare genetic disease resulting in unpredictable and potentially life-threatening subcutaneous and submucosal attacks mediated by the vasoactive peptide, bradykinin. HAE often presents within the first or second decade of life, with attacks increasing in both frequency and severity over time. First-line therapies exert their action by replacing C1 inhibitor (C1-INH) or via blocking the production or function of bradykinin. Cinryze^® is a nanofiltered C1-INH, approved in Europe for the acute treatment, preprocedure prevention and routine prophylaxis of HAE attacks, and for routine prophylaxis of attacks in the USA. Of the current C1-INH preparations available, Cinryze shows particular promise in the safe and effective treatment and prophylaxis of HAE attacks in pediatric age patients.

BACKGROUND:We conducted our first patient survey at the 2013 hereditary angioedema (HAE) patient summit and learned that, despite several novel therapies, the burden of disease was high. OBJECTIVE:To determine, from the patient's perspective, if any improvements in the current state of HAE care occurred over a two-year period between HAE patient summits. METHODS:A patient survey was conducted at the 2015 Hereditary Angioedema Association conference by using paper surveys that aimed at understanding the current state of HAE care. Questions included patient characteristics, burden of disease, and satisfaction with care and treatment options. Comparisons between patients with HAE with C1-inhibitor (HAE-C1INH) and patients with HAE with normal C1-inhibitor (HAE-nlC1INH), as well as between patients with HAE in 2013 and 2015, were performed by using χ2 tests. RESULTS:There were 232 surveys distributed, and 143 surveys were identified as complete for inclusion and analysis from patients with self-reported HAE. Most patients had type I or type II HAE (67.5% [n = 106]), with a smaller number of patients with HAE-nlC1INH (23.6% [n = 37]). In 2015, almost half of the patients with HAE-C1INH (47.1%) and 56.7% of the patients with HAE-nlC1INH experienced a delay of ≥10 years between initial symptoms and diagnosis. Among the patients with HAE-C1INH, 25% reported one or more attacks per week and another 48% reported experiencing one or more attacks per month (fewer than one attack per week). The patients with HAE-nlC1INH reported attacks more frequently than did the patients with HAE-C1INH (p = 0.002), with 59.5% who reported attacks at least once a week. Emergency care was reported one or more times per month in 5% of the patients with HAE-C1INH and in 24.3% of the patients with HAE-nlC1INH. CONCLUSION/CONCLUSIONS:Similar to 2013, although significant progress has been made, there is still a high burden of disease that faces patients with HAE.

BACKGROUND:Hereditary angioedema (HAE) is a rare genetic disorder with substantial morbidity and mortality. Despite expanded choices for effective acute treatment, prophylactic options are more limited. Intravenous C1 esterase inhibitor (C1-INH[IV]) is licensed and used to prevent HAE symptoms. OBJECTIVE:To better understand patient experiences with using C1-INH(IV), including level of satisfaction and types and frequency of complications. METHODS:Fifty adult members (≥18 years of age) of the US HAE Association who had HAE type I or II completed a self-administered internet survey. Eligible participants were experiencing at least 1 HAE attack per month and must have been receiving treatment with C1-INH(IV) as prophylaxis or acute therapy. RESULTS:Almost all respondents (n = 47; 94%) were using C1-INH(IV) for HAE prophylaxis. Most patients reported administration of C1-INH(IV) through a peripheral vein (n = 34) and 19 were currently (n = 17) or previously (n = 2) using a central venous port. Most respondents (62%) who used a peripheral vein to administer treatment reported having difficulty finding a usable vein or getting the infusion to work properly at least some of the time. Issues accessing veins, exhausted veins, and frequency of attacks were the main reasons physicians recommended ports to respondents. Although ports allow easier administration of therapy, 47% of respondents with ports experienced problems such as occlusion, thrombosis, and infection. Respondents using C1-INH prophylaxis reported a mean of 2.3 attacks per month during the previous 6 months. CONCLUSION:The survey results identified clinical challenges with IV HAE medication use, including venous access issues and ongoing monthly attack occurrence despite prophylactic C1-INH(IV) administration.

BACKGROUND:Hereditary angioedema with C1 inhibitor deficiency is characterized by recurrent, unpredictable swelling episodes caused by uncontrolled plasma kallikrein generation and excessive bradykinin release resulting from cleavage of high-molecular-weight kininogen. Lanadelumab (DX-2930) is a new kallikrein inhibitor with the potential for prophylactic treatment of hereditary angioedema with C1 inhibitor deficiency. METHODS:We conducted a phase 1b, multicenter, double-blind, placebo-controlled, multiple-ascending-dose trial. Patients with hereditary angioedema with C1 inhibitor deficiency were randomly assigned in a 2:1 ratio to receive either lanadelumab (24 patients) or placebo (13 patients), in two administrations 14 days apart. Patients assigned to lanadelumab were enrolled in sequential dose groups: total dose of 30 mg (4 patients), 100 mg (4 patients), 300 mg (5 patients), or 400 mg (11 patients). The pharmacodynamic profile of lanadelumab was assessed by measurement of plasma levels of cleaved high-molecular-weight kininogen, and efficacy was assessed by the rate of attacks of angioedema during a prespecified period (day 8 to day 50) in the 300-mg and 400-mg groups as compared with the placebo group. RESULTS:No discontinuations occurred because of adverse events, serious adverse events, or deaths in patients who received lanadelumab. The most common adverse events that emerged during treatment were attacks of angioedema, injection-site pain, and headache. Dose-proportional increases in serum concentrations of lanadelumab were observed; the mean elimination half-life was approximately 2 weeks. Lanadelumab at a dose of 300 mg or 400 mg reduced cleavage of high-molecular-weight kininogen in plasma from patients with hereditary angioedema with C1 inhibitor deficiency to levels approaching that from patients without the disorder. From day 8 to day 50, the 300-mg and 400-mg groups had 100% and 88% fewer attacks, respectively, than the placebo group. All patients in the 300-mg group and 82% (9 of 11) in the 400-mg group were attack-free, as compared with 27% (3 of 11) in the placebo group. CONCLUSIONS:In this small trial, administration of lanadelumab to patients with hereditary angioedema with C1 inhibitor deficiency reduced cleavage of high-molecular-weight kininogen and attacks of angioedema. (Funded by Dyax; ClinicalTrials.gov number, NCT02093923 .).