Effect of lanadelumab on attack frequency and QoL in Japanese patients with hereditary angioedema: Report of five cases.

Lanadelumab, a recombinant human anti-kallikrein monoclonal antibody, is recommended as the first-line option for long-term prophylaxis (LTP) in hereditary angioedema (HAE). However, the efficacy of lanadelumab and its effects on the quality of life (QoL) in Japanese HAE patients using real-world data have not been reported. Herein, we report the outcomes of five HAE patients who were treated with lanadelumab at two Japanese institutions. We retrospectively collected data on attack frequency and on-demand treatment frequency using an angioedema quality of life (AE-QoL) questionnaire. Our data corresponded to five Japanese HAE patients who started lanadelumab treatment: four with HAE due to C1-inhibitor deficiency (HAE-1) and one with HAE with a normal C1-inhibitor (HAE-nC1-INH). Two HAE-1 patients showed a reduction in both attacks and number of on-demand treatments. The other HAE-1 patients had an increase in the number of on-demand treatments, although there was no apparent reduction in attacks. The HAE-nC1-INH patient showed a slight increase in both attacks and number of on-demand treatments. Only one HAE-1 patient discontinued treatment after 1 month owing to side effects, including dizziness and headache. All four who continued treatment showed improved AE-QoL total and domain scores. Therefore, in this study, using real-world data, we demonstrated that lanadelumab reduced attack frequency and improved QoL in Japanese HAE patients.

Indirect Comparison of Lanadelumab and Intravenous C1-INH Using Data from the HELP and CHANGE Studies: Bayesian and Frequentist Analyses.

BACKGROUND: Hereditary angioedema (HAE) with C1-esterase inhibitor (C1-INH) deficiency is a rare disease associated with painful, potentially fatal swelling episodes affecting subcutaneous or submucosal tissues. HAE attacks recur with unpredictable severity and frequency throughout patients' lives; long-term prophylaxis is essential for some patients. In the absence of head-to-head studies, indirect treatment comparison (ITC) of long-term prophylactic agents is a valid approach to evaluate comparative efficacy. METHODS: We conducted an ITC using data from the placebo-controlled HELP study (assessing patients receiving lanadelumab 300 mg every 2 or 4 weeks) and the 12-week, parallel arm, crossover CHANGE study (assessing intravenous C1-INH). Outcomes of interest were attack rate ratio (ARR) and time to attack after day 0 (TTA0) and after day 70 (TTA70). Two ITC methodologies were used: a Bayesian approach using study results to update non-informative prior distributions to posterior distributions on relative treatment effects, and a frequentist approach using patient-level data from HELP and CHANGE to generate Poisson regressions (for ARR) and Cox models (for TTA0 and TT70). RESULTS: Both Bayesian and frequentist analyses suggested that lanadelumab reduced HAE attack rate by 46-73% versus intravenous C1-INH. Relative to intravenous C1-INH, risk of first attack after day 0 was comparable between intravenous C1-INH and both lanadelumab doses; risk of first attack after day 70 was reduced by 81-83% with lanadelumab 300 mg every 2 weeks, compared with C1-INH. CONCLUSIONS: Findings from these two ITC methodologies support the favorable efficacy of lanadelumab in reducing the HAE attack rate and extending attack-free intervals in patients with HAE.

Assessing the cost and quality-of-life impact of on-demand-only medications for adults with hereditary angioedema.

Background: Novel subcutaneous (SC) prophylactic therapies are transforming the treatment landscape of hereditary angioedema (HAE). Although questions are being raised about their cost, little attention has been paid to the cost and quality of life (QoL) impact of using on-demand-only medications. Objective: We assessed the overall economic burden of on-demand-only treatment for HAE and compared patient QoL with patients who received novel SC prophylactic therapies. Methods: US Hereditary Angioedema Association members were invited to complete an anonymous online survey to profile attack frequency, treatment use, and the presence of comorbidities as well as economic and socioeconomic variables. We modeled on-demand treatment costs by using net pricing of medications in 2018, indirect patient and caregiver costs, and attack-related direct billed costs for emergency department admissions, physician office visits, and/or hospitalizations. QoL was assessed by using the Angioedema Quality of Life questionnaire. Results: A total of 1225 patients (31.4%) responded. Of these, 737 adults with HAE (type I or II) met the inclusion criteria and completed the survey. Per patient/year direct costs associated with modeled on-demand-only treatment totaled $363,795, with additional indirect socioeconomic costs of $52,576 per patient/year. The greatest improvement in QoL was seen in patients who used novel SC prophylactic therapies, with a 59.5% (p < 0.01) improvement in median impairment scores versus on-demand-only treatment. In addition, patients who used novel SC prophylactic therapies reported a 77% reduction in the number of attacks each year when compared with those who used on-demand-only treatment. Conclusion: Our real-world patient data showed the cost and QoL burden of HAE treatment with on-demand-only therapy. Use of novel SC prophylaxis can lead to sizeable reductions in attack frequency and statistically significant and clinically relevant improvements in QoL. These data could be useful to clinicians and patients as they consider therapy options for patients with HAE.

Evaluation of the efficacy and safety of icatibant and C1 esterase/kallikrein inhibitor in severe COVID-19: study protocol for a three-armed randomized controlled trial.

BACKGROUND: SARS-CoV-2, the virus that causes COVID-19, enters the cells through a mechanism dependent on its binding to angiotensin-converting enzyme 2 (ACE2), a protein highly expressed in the lungs. The putative viral-induced inhibition of ACE2 could result in the defective degradation of bradykinin, a potent inflammatory substance. We hypothesize that increased bradykinin in the lungs is an important mechanism driving the development of pneumonia and respiratory failure in COVID-19. METHODS: This is a phase II, single-center, three-armed parallel-group, open-label, active control superiority randomized clinical trial. One hundred eighty eligible patients will be randomly assigned in a 1:1:1 ratio to receive either the inhibitor of C1e/kallikrein 20 U/kg intravenously on day 1 and day 4 plus standard care; or icatibant 30 mg subcutaneously, three doses/day for 4 days plus standard care; or standard care alone, as recommended in the clinical trials published to date, which includes supplemental oxygen, non-invasive and invasive ventilation, antibiotic agents, anti-inflammatory agents, prophylactic antithrombotic therapy, vasopressor support, and renal replacement therapy. DISCUSSION: Accumulation of bradykinin in the lungs is a common side effect of ACE inhibitors leading to cough. In animal models, the inactivation of ACE2 leads to severe acute pneumonitis in response to lipopolysaccharide (LPS), and the inhibition of bradykinin almost completely restores the lung structure. We believe that inhibition of bradykinin in severe COVID-19 patients could reduce the lung inflammatory response, impacting positively on the severity of disease and mortality rates. TRIAL REGISTRATION: Brazilian Clinical Trials Registry Universal Trial Number (UTN) U1111-1250-1843. Registered on May/5/2020.

Recombinant human C1 esterase inhibitor (conestat alfa) in the prevention of severe SARS-CoV-2 infection in hospitalized patients with COVID-19: A structured summary of a study protocol for a randomized, parallel-group, open-label, multi-center pilot trial (PROTECT-COVID-19).

OBJECTIVES: Conestat alfa, a recombinant human C1 esterase inhibitor, is a multi-target inhibitor of inflammatory cascades including the complement, the kinin-kallikrein and the contact activation system. The study objective is to investigate the efficacy and safety of conestat alfa in improving disease severity and short-term outcome in COVID-19 patients with pulmonary disease. TRIAL DESIGN: This study is an investigator-initiated, randomized (2:1 ratio), open-label, parallel-group, controlled, multi-center, phase 2a clinical trial. PARTICIPANTS: This trial is conducted in 3 hospitals in Switzerland, 1 hospital in Brazil and 1 hospital in Mexico (academic and non-academic). All patients with confirmed SARS-CoV-2 infection requiring hospitalization for at least 3 calendar days for severe COVID-19 will be screened for study eligibility. INCLUSION CRITERIA: - Signed informed consent - Age 18-85 years - Evidence of pulmonary involvement on CT scan or X-ray of the chest - Duration of symptoms associated with COVID-19 ≤ 10 days - At least one of the following risk factors for progression to mechanical ventilation on the day of enrolment: 1) Arterial hypertension 2) ≥ 50 years 3) Obesity (BMI ≥ 30 kg/m2) 4) History of cardiovascular disease 5) Chronic pulmonary disease 6) Chronic renal disease 7) C-reactive protein > 35mg/L 8) Oxygen saturation at rest of ≤ 94% when breathing ambient air Exclusion criteria: - Incapacity or inability to provide informed consent - Contraindications to the class of drugs under investigation (C1 esterase inhibitor) - Treatment with tocilizumab or another IL-6R or IL-6 inhibitor before enrolment - History or suspicion of allergy to rabbits - Pregnancy or breast feeding - Active or anticipated treatment with any other complement inhibitor - Liver cirrhosis (any Child-Pugh score) - Admission to an ICU on the day or anticipated within the next 24 hours of enrolment - Invasive or non-invasive ventilation - Participation in another study with any investigational drug within the 30 days prior to enrolment - Enrolment of the study investigators, their family members, employees and other closely related or dependent persons INTERVENTION AND COMPARATOR: Patients randomized to the experimental arm will receive conestat alfa in addition to standard of care (SOC). Conestat alfa (8400 U followed by 4200 U every 8 hours) will be administered as a slow intravenous injection (5-10 minutes) over a 72-hour period (i.e. 9 administrations in total). The first conestat alfa treatment will be administered on the day of enrolment. The control group will receive SOC only. SOC treatment will be administered according to local institutional guidelines, including supplemental oxygen, antibiotics, corticosteroids, remdesivir, and anticoagulation. MAIN OUTCOMES: The primary endpoint of this trial is disease severity on day 7 after enrolment assessed by an adapted WHO Ordinal Scale for Clinical Improvement (score 0 will be omitted and score 6 and 7 will be combined) from 1 (no limitation of activities) to 7 (death). Secondary outcomes include (i) the time to clinical improvement (time from randomization to an improvement of two points on the WHO ordinal scale or discharge from hospital) within 14 days after enrolment, (ii) the proportion of participants alive and not having required invasive or non-invasive ventilation at 14 days after enrolment and (iii) the proportion of subjects without an acute lung injury (defined by PaO2/FiO2 ratio of ≤300mmHg) within 14 days after enrolment. Exploratory outcomes include virological clearance, C1 esterase inhibitor pharmacokinetics and changes in routine laboratory parameters and inflammatory proteins. RANDOMISATION: Subjects will be randomised in a 2:1 ratio to treatment with conestat alfa in addition to SOC or SOC only. Randomization is performed via an interactive web response system (SecuTrial®). BLINDING (MASKING): In this open-label trial, participants, caregivers and outcome assessors are not blinded to group assignment. NUMBERS TO BE RANDOMISED (SAMPLE SIZE): We will randomise approximately 120 individuals (80 in the active treatment arm, 40 in the SOC group). Two interim analyses after 40 and 80 patients are planned according to the Pocock adjusted levels αp = 0.0221. The results of the interim analysis will allow adjustment of the sample size (Lehmacher, Wassmer, 1999). TRIAL STATUS: PROTECT-COVID-19 protocol version 3.0 (July 07 2020). Participant recruitment started on July 30 2020 in one center (Basel, Switzerland, first participant included on August 06 2020). In four of five study centers patients are actively recruited. Participation of the fifth study center (Mexico) is anticipated by mid December 2020. Completion of trial recruitment depends on the development of the SARS-CoV-2 pandemic. TRIAL REGISTRATION: Clinicaltrials.gov, number: NCT04414631 , registered on 4 June 2020 FULL PROTOCOL: The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest of expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

Long-Term Efficacy of Subcutaneous C1 Inhibitor in Pediatric Patients with Hereditary Angioedema.

Background: Hereditary angioedema (HAE) due to C1 inhibitor (C1INH) deficiency is characterized by recurrent attacks of edema of the skin and mucosal tissues. Symptoms usually present during childhood (mean age at first attack, 10 years). Earlier symptom onset may predict a more severe disease course. Subcutaneous (SC) C1INH is indicated for routine prophylaxis to prevent HAE attacks in adolescents and adults. We analyzed the long-term efficacy of C1INH (SC) in subjects ≤17 years old treated in an open-label extension (OLE) of the pivotal phase III Clinical Study for Optimal Management of Preventing Angioedema with Low-Volume Subcutaneous C1 Inhibitor Replacement Therapy (COMPACT) trial. Methods: Eligible subjects (age ≥6 years, with ≥4 attacks over 2 consecutive months before entry into the OLE or placebo-controlled COMPACT trial) were treated with C1INH (SC) 40 or 60 IU/kg twice weekly for 52-140 weeks. Subgroup analyses by age (≤17 vs. >17 years) were performed for key efficacy endpoints. Results: Ten subjects were ≤17 years old [mean (range) age, 13.3 (8-16) years, 3 subjects <12 years old; exposure range, 51-133 weeks]. All 10 pediatric subjects experienced ≥50% reduction (mean, 93%) in number of attacks versus the prestudy period, with a 97% reduction in the median number of attacks/month (0.11). All subjects had <1 attack/4-week period and 4 had <1 attack/year (1 subject was attack free). No subject discontinued treatment due to a treatment-related adverse event. Conclusions: Data from pediatric subjects treated with C1INH (SC) for up to 2.55 years and adult subjects revealed similar efficacy. C1INH (SC) is effective and well tolerated as long-term prophylaxis in children, adolescents, and adults with HAE.

[EFFICACY, PHARMACOKINETICS, PHARMACODYNAMICS, AND SAFETY OF INTRAVENOUS C1 INHIBITOR FOR LONG-TERM PROPHYLAXIS AND TREATMENT OF BREAKTHROUGH ATTACKS IN JAPANESE SUBJECTS WITH HEREDITARY ANGIOEDEMA: A PHASE 3 OPEN-LABEL STUDY].

BACKGROUND: Hereditary angioedema (HAE) is associated with recurrent, painful, and potentially lifethreatening attacks characterized by swelling of subcutaneous or submucosal tissues. PURPOSE: To investigate the efficacy, safety, pharmacokinetics, and pharmacodynamics of repeat-use C1 inhibitor (C1-INH) replacement therapy for long-term prophylaxis and treatment of breakthrough attacks in the management of Japanese patients with HAE type I or II. METHODS: An open-label, single-arm, Phase 3 study was conducted in Japanese patients with HAE (NCT02865720). For patients 6 years of age or older, 1000U were administered biweekly (by a healthcare professional or self-administered) via intravenous infusion. RESULTS: In 8 enrolled patients, the mean number of attacks normalized per month was lower during C1-INH treatment than during the 3 months prior (1.826 vs. 3.375). Clinically meaningful mean change from baseline in the angioedema-quality of life (AE-QoL) total score was shown during treatment with C1-INH. Pharmacokinetic data showed markedly higher and enduring post-baseline plasma levels of C1-INH functional activity and C1-INH antigen concentration, starting from 0.5h after first dose of C1-INH and lasting up to 72 hours. C1-INH was well tolerated with no new safety signals identified in this population of Japanese patients with HAE. CONCLUSION: C1-INH was effective for long-term prophylaxis and treatment of breakthrough attacks with favourable safety profile in Japanese patients with HAE.

Advances in Hereditary Angioedema: The Prevention of Angioedema Attacks With Subcutaneous C1-Inhibitor Replacement Therapy.

Hereditary angioedema (HAE) is a debilitating condition caused by a functional C1-inhibitor (C1-INH) deficiency and characterized clinically by episodes of subcutaneous or submucosal swelling. C1-INH replacement is highly effective for preventing HAE attacks and can improve health-related quality of life. Once available only for intravenous use, C1-INH is now available as a subcutaneous formulation for self-administration, shown to provide sustained plasma levels of C1-INH and reducing the monthly median HAE attack rate by 95% versus placebo in the phase 3 COMPACT study. Subcutaneously administered C1-INH satisfies multiple unmet needs in the management of patients with HAE.

Evaluation of the efficacy and safety of home treatment with the recombinant human C1-inhibitor in hereditary angioedema resulting from C1-inhibitor deficiency.

OBJECTIVE: Conestat alpha, a C1-inhibitor produced by recombinant technology (rhC1-INH) is an acute treatment for edematous attacks occurring in hereditary angioedema (HAE) with C1-inhibitor deficiency (C1-INH-HAE). Our study evaluated the efficacy and safety of rhC1-INH administered during HAE attacks, and for short-term prophylaxis (STP). MATERIALS & METHOD: Our prospective study analyzed the course of 544 HAE attacks experienced by the 21 C1-INH-HAE patients treated, as well as the outcome of 97 instances of STP implemented with rhC1-INH. Using a purpose-designed questionnaire, the patients recorded relevant, treatment-related information. RESULTS: Time to the administration of rhC1-INH was 90.0 min (median) after the onset of HAE attacks. The symptoms started to improve as early as 60 min after the injection of rhC1-INH, and the attack resolved 730.0 min after treatment. The interval between the onset of the HAE attack and the administration of rhC1-INH correlated with time until the onset of improvement (R = 0.2053 p < 0.0001), and with time to the complete resolution of symptoms (R = 0.2805, p < 0.0001). Nine patients received STP with rhC1-INH in 97 instances. STP successfully prevented the HAE attack within 72 h of the event on 93/97 occasions. No local and serious systemic adverse events/effects were observed. CONCLUSIONS: Treatment with rhC1-INH is effective and safe both for acute management, and for STP. Following the onset of an HAE attack, early administration of rhC1-INH may reduce time to the improvement and to the complete resolution of symptoms. Repeated administration of rhC1-INH does not impair its efficacy.

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

BACKGROUND: Hereditary angioedema (HAE) is a rare C1-inhibitor (C1-INH) deficiency disease. Low levels of functional C1-INH can lead to recurrent attacks of severe swelling occurring in areas such as the limbs, face, gastrointestinal tract, and throat. These attacks are both painful and disabling and, if not treated promptly and effectively, can result in hospitalization or death. Agents targeting the specific physiologic pathway of HAE attacks can offer improved outcomes with limited side effects compared with nonspecific therapies. However, these treatments display varying efficacy in HAE patients, including the need to redose or seek additional care if the treatment does not resolve symptoms effectively. OBJECTIVE: To analyze the expected cost and utility per HAE attack when treated on-demand with HAE therapies indicated for the treatment of acute attacks. METHODS: A decision-tree model was developed using TreeAge Pro software. Four on-demand HAE treatments were included: ecallantide, icatibant, plasma-derived (pd)C1-INH, and recombinant human (rh)C1-INH. The model uses probabilities for redosing, self-administration versus health care provider administration, and risk of hospitalization. Costs within the model consisted of the HAE treatments and associated health care system expenses. Nonattack baseline utility and attack utility were implemented for effectiveness calculations; time to attack resolution was considered as well. Effectiveness and overall costs per attack were calculated and used to estimate cost per quality-adjusted life-year (QALY). Variability and ranges in cost-effectiveness were determined using probabilistic sensitivity analyses. Finally, a budget impact model for a health plan with 1 million covered lives was also developed. RESULTS: The base case model outputs show costs and calculated effectiveness per attack at $12,905 and 0.806 for rhC1-INH, $14,806 and 0.765 for icatibant, $14,668 and 0.769 for pdC1-INH, and $21,068 and 0.792 for ecallantide, respectively. Cost per QALY was calculated using 26.9 attacks per person-year, leading to results of $420,941 for rhC1-INH, $488,349 for icatibant, $483,892 for pdC1-INH, and $689,773 for ecallantide. Sensitivity analyses demonstrate that redose rates (from 3% for rhC1-INH to 44% for icatibant) are a primary driver of variability in cost-effectiveness. Annual health plan costs from the budget impact model are calculated as $6.94 million for rhC1-INH, $7.97 million for icatibant, $7.90 million for pdC1-INH, and $11.33 million for ecallantide. CONCLUSIONS: Accounting for patient well-being and additional cost components of HAE attacks generates a better estimation of cost-effectiveness than drug cost alone. Results from this model indicate that rhC1-INH is the dominant treatment option with lower expected costs and higher calculated effectiveness than comparators. Further analyses reinforce the idea that low redose rates contribute to improved cost-effectiveness. DISCLOSURES: Funding support was contributed by Pharming Healthcare. Relan and Adams are employed by Pharming Healthcare. Tyson and Magar are employed by AHRM, which received fees to perform the analysis and develop the manuscript. Bernstein reports grants, personal fees, and nonfinancial support from Shire, CSL Behring, and Pharming Healthcare; grants and personal fees from Biocryst; and nonfinancial support from HAEA, unrelated to this study.

C1 esterase inhibitor in pediatric cardiac surgery with cardiopulmonary bypass plays a vital role in activation of the complement system.

Our prospective study was therefore designed to determine which part of the systemic inflammatory response after cardiac operations resulted from Cardiopulmonary bypass (CPB) in neonates and infants. After approval by the human ethical committee of the Gunma Children's Medical Center (GCMC) and informed consent of the parents, 40 consecutive term congenital heart disease patients aged until 1 year who underwent long CPB time (> 3 h) at surgery were included in the prospective study between January 2012 and December 2014. C1 esterase inhibitor (C1-inh) drug (@Berinert) was generously provided by CSL Behring (King of Prussia, PA). The C1-inh (20 IU/kg) was given intravenously 60 min after CPB. Blood samples for complement factors were obtained before and 48 h after administration of C1-inh. Six patients did not survive and their data were not included. Of 34 patients included, median age was 6.5 months, median body weight was 6050 g, and 16 (47%) were female. According to the Mann-Whitney U test, there were no differences between the two groups concerning demographic and intraoperative data, postoperative chemical data. C1q concentration was only significant lower in patients with C1-inh non-treated group than in patients with C1-inh treated group. But, the consumption of C1q, C3, C4, CH50, and C1-inh in patients with C1-inhibitor non-treated group was observed early postoperatively. There is a significant difference in the values before and after C1-inh treatment between the two groups. The lower value in the C1-inh-treated group is explained by the activation of the classical pathway through the replenishment of complements by C1-inh treatment. This study proposes the administration of C1-inh is an effective therapy to reduce the activation and improve the clinical capillary leak syndrome.

Hereditary angioedema in children: a review and update.

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.

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

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

The Effectiveness and Value of Lanadelumab and C1 Esterase Inhibitors for Prophylaxis of Hereditary Angioedema Attacks.

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.

Update on the Use of C1-Esterase Inhibitor Replacement Therapy in the Acute and Prophylactic Treatment of Hereditary Angioedema.

In the vast majority of patients with hereditary angioedema (HAE), angioedema attacks are due to the quantitative or functional deficiency of C1-esterase inhibitor (C1-INH), which leads to increased vascular permeability and unregulated release of bradykinin. Exogenous administration of C1-INH is a rational way to restore the concentration and functional activity of this protein, regulate the release of bradykinin, and attenuate or prevent subcutaneous and submucosal edema associated with HAE. Recent international guidelines for the management of HAE include C1-INH as an option for acute treatment of HAE. In addition, these guidelines recommend C1-INH as first-line treatment for long-term prophylaxis and as the therapy of choice for short-term/preprocedural prophylaxis. Several C1-INH products are available, with approved indications varying across regions. For the acute treatment of HAE, both plasma-derived and recombinant C1-INH formulations have been shown to be effective and well tolerated in adolescents and adults with HAE, with onset of relief within 30 min to a few hours. Plasma-derived C1-INH is approved for use in children, and recombinant C1-INH is being evaluated in this population. Intravenous (IV) and subcutaneous (SC) formulations of C1-INH have been approved for routine prophylaxis to prevent HAE attacks in adolescents and adults. Both formulations when administered twice weekly have been shown to reduce the frequency and severity of HAE attacks. The SC formulation of C1-INH obviates the need for repeated venous access and may facilitate self-administration of HAE prophylaxis at home, as recommended in HAE treatment guidelines. As with most rare diseases, the costs of HAE treatment are high; however, the development of additional acute and prophylactic medications for HAE may result in competitive pricing and help drive down the costs of HAE treatment.

Treatment of Hereditary Angioedema Attacks with Icatibant and Recombinant C1 Inhibitor During Pregnancy.

PURPOSE: Hereditary angioedema (HAE) is a rare disease caused by a C1 inhibitor (C1-INH) deficit. Clinically, HAE is manifested by repeated episodes of localized subcutaneous or submucosal oedema attacks. Managing HAE patients in pregnancy is challenging, since there are only limited data on the safety and efficacy of various therapeutic approaches. METHODS: We present our clinical experience treating acute HAE attacks during pregnancy in six consecutive patients. RESULTS: During the pregnancies, 79 HAE attacks occurred. The most frequent were abdominal 53 (67.1%) followed by peripheral 21 (26.6%), facial 10 (12.7%), and laryngeal 10 (12.7%) oedemas; 13 (16.5%) attacks were combined. Fifty (63.3%) attacks were treated with recombinant human C1-INH (rhC1-INH); 17 (21.5%) with plasma-derived, pasteurized, nanofiltered C1-INH (pnfC1-INH); 13 (16.5%) with icatibant; and 1 (1.3%) with plasma-derived, nanofiltered C1-INH (nfC1-INH). Treatment had to be repeated in 5 attacks (6.3%). All six deliveries (one caesarean section and five spontaneous vaginal deliveries) were complication free. All pregnancies went to the full term and the patients delivered healthy babies with a birth weight ranging from 2850 to 3690 g. No congenital abnormalities were detected in the neonates. No abortions occurred. CONCLUSIONS: Our results show good C1-INH or icatibant treatment efficacy for HAE attacks in pregnancy. The treatment by the first drug used was effective in 93.7% of all attacks. In 6.3% of attacks, a second treatment had to be used. No adverse effects were observed.

Subcutaneous C1-esterase inhibitor to prevent hereditary angioedema attacks: Safety findings from the COMPACT trial.

BACKGROUND: The first subcutaneous (SC) C1-esterase inhibitor concentrate (C1-INH) was approved by the U.S. Food and Drug Administration in June 2017 as routine prophylaxis to prevent hereditary angioedema attacks in adolescents and adults at a dose of 60 IU/kg twice weekly based on the phase III Clinical Study for Optimal Management of Preventing Angioedema With Low-volume Subcutaneous C1-Inhibitor Replacement Therapy (COMPACT) trial. OBJECTIVE: This article aimed to evaluate the relationship of the C1-INH (SC) dose regimens tested in the COMPACT trial (40 IU/kg and 60 IU/kg twice weekly) and the occurrence of adverse events (AEs). METHODS: Patients were instructed to record any AEs in their e-diary daily. Safety and tolerability were assessed based on reported AEs, including injection-site reactions (ISRs); unsolicited AEs (AEs other than ISRs); serious AEs; thrombotic, thromboembolic, anaphylactic, hypersensitivity, sepsis, and bacteremia events; inhibitory antibodies to C1-INH; and clinically significant abnormalities in laboratory assessments. Information on ISRs was specifically solicited. RESULTS: No relationship between the dose of C1-INH (SC) and the incidence of ISRs or unsolicited AEs was observed. The proportion of injections followed by at least one ISR was 12% with C1-INH (SC) 40 IU/kg versus 5% with 60 IU/kg and 6% with placebo. No ISRs were serious or led to treatment discontinuation, and all resolved. There were no anaphylaxis, thromboembolic, sepsis, or bacteremia events reported during treatment with C1-INH (SC). All hypersensitivity AEs were nonserious, and the majority were assessed as being unrelated to treatment. No inhibitory antibodies to C1-INH were observed. CONCLUSION: C1-INH (SC) is safe and well tolerated with no dose-dependent safety concerns, as demonstrated in the COMPACT trial.Clinical trial NCT01912456, www.clinicaltrials.gov.