Idiopathic non-histaminergic acquired angioedema (InH-AAE) is a rare disease, with unknown etiology and pathogenesis, characterized by recurrent clinical manifestations and resistance to antihistamines and corticosteroids. We aim to evaluate clinical features and potential markers of disease in an Italian cohort of patients with InH-AAE. We enrolled 26 patients diagnosed with InH-AAE. Information about clinical features, treatments, routine laboratory investigations, immunological and genetic tests were collected. We assessed plasma levels of complement components, angiogenic and lymphangiogenic mediators, proinflammatory cytokines and chemokines, and activity of phospholipases A2. Finally, patients underwent nailfold videocapillaroscopy (NVC); both quantitative and qualitative capillaroscopic parameters were analyzed. Plasma levels of VEGFs were similar in healthy controls and in InH-AAE patients. ANGPT1 was decreased in InH-AAE patients compared to controls while ANGPT2 was similar to controls. Interestingly, the ANGPT2/ANGPT1 ratio (an index of vascular permeability) was increased in InH-AAE patients compared to controls. sPLA2 activity, elevated in patients with C1-INH-HAE, showed differences also when measured in InH-AAE patients. TNF-α concentration was higher in InH-AAE patients than in healthy controls, conversely, the levels of CXCL8, and IL-6 were similar in both groups. At the NVC, the capillary loops mainly appeared short and tortuous in InH-AAE patients. InH-AAE represents a diagnostic challenge. Due to the potential life-threatening character of this condition, a prompt identification of the potentially bradykinin-mediated forms is crucial. A better comprehension of the mechanism involved in InH-AAE would also lead to the development of new therapeutic approaches to improve life quality of patients affected by this disabling disease.

BACKGROUND: Determination of control level in recurrent angioedema (RAE) is necessary to guide management. Here, we validated a Turkish version of the angioedema control test (AECT) for 4-week (AECT-4wk) and for 3-month (AECT-3mth) and assessed their utility in monitoring RAE.
METHODS: The recommended structured translation process for patient-reported outcome measures was completed. The final versions were administered to 51 patients with mast cell-mediated angioedema (MMAE) and 38 patients with hereditary angioedema, and the minimal clinically important difference (MCID) was determined. Additionally, anchor surveys comprising angioedema activity score for 28 days (AAS-28 day), visual analog score for angioedema control, Likert scale for the control level from the patient\'s perspective (LS-AEC), angioedema quality of life, short form-12 (SF-12) and patients\' assessment of treatment sufficiency were applied.
RESULTS: The Turkish AECT versions showed good convergent validity with a substantial correlation with anchor tools and known-group validity. Excellent internal consistency and reproducibility were observed. Equal or more than 10 of 16 points scored with the AECT-4wk and AECT-3mth identified patients with well-controlled disease. The disease activity, control and burden parameters were consistent with the disease control level defined depending on the cut-off point 10 of AECT. Three-point changes in AECT-4wk and -3 mt could detect MCID in disease control in all patients.
CONCLUSIONS: Turkish AECT versions are valid and reliable tools for assessing and monitoring disease control in patients with RAE. The use of the Turkish versions of the AECT in routine patient care, clinical trials and angioedema research is recommended.

BACKGROUND: Hereditary angioedema (HAE) is a rare potentially life-threatening genetic disorder characterized by recurrent episodes of angioedema without wheals that can affect any part of the body. The unpredictability of the attacks and the risk of passing the disease to the offspring result in significant physical and emotional burdens for patients, with a negative impact on quality of life. Data about the health-related quality of life in HAE patients from Romania are scarce. This study aimed to evaluate the disease-specific quality of life in patients with HAE from Romania and to determine associated factors.
METHODS: The study included adult patients with HAE enrolled in the Romanian HAE Registry. Disease-specific quality of life was measured using the Hereditary Angioedema Quality of Life questionnaire, a cross-culturally adapted, internationally validated structured survey.
RESULTS: The survey was completed by 94 patients (64.9% females; 35.1% males). The mean age of the participants was 44.9 years (SD 14.1). Most patients (88.3%) had type I HAE and were from urban areas (63.8%). The mean ages at symptom onset and diagnosis were 15.1 (SD 11.1) and 36.1 (SD 14.1) years, respectively. The mean diagnosis delay was 20.5 years (SD 14.2). In the evaluated period, all patients had at least one vial of on-demand treatment at home, and 10 were on long-term prophylaxis treatment. The general and dimensional quality of life scores were slightly above the median values of the reference scales. While the general score was not associated with sex or residence, a statistically significant, negative, weak correlation was detected with diagnostic delay.
CONCLUSIONS: The results suggest that despite the availability of on-demand treatment for all patients, there is a need for other diagnostic and therapeutic interventions to improve the management of the disease and the quality of life for HAE patients from Romania.

Hereditary angioedema (HAE) is a potentially fatal disease characterized by unpredictable, recurrent, often disabling swelling attacks. In a randomized phase 2 study, donidalorsen reduced HAE attack frequency and improved patient quality-of-life (ISIS721744-CS2, NCT04030598). We report the 2-year interim analysis of the phase 2 open-label extension (OLE) study (ISIS 721744-CS3, NCT04307381).
In the OLE, the on-treatment study period consisted of fixed (weeks 1-13, donidalorsen 80 mg subcutaneously every 4 weeks [Q4W]) and flexible (weeks 17-105, donidalorsen 80 mg Q4W, 80 mg every 8 weeks [Q8W], or 100 mg Q4W) dosing periods. The primary outcome was incidence and severity of treatment-emergent adverse events (TEAEs). The secondary outcomes included efficacy, pharmacodynamic, and quality-of-life assessments.
Seventeen patients continued in the OLE study. No serious TEAEs or TEAEs leading to treatment discontinuation were reported. Mean monthly HAE attack rate was 96% lower than the study run-in baseline rate (mean, 0.06/month; 95% confidence interval [CI], 0.02-0.10; median, 0.04 on-treatment vs. mean, 2.70/month; 95% CI, 1.94-3.46; median, 2.29 at baseline). Mean monthly attack rate for Q8W dosing (n = 8) was 0.29 (range, 0.0-1.7; 95% CI, -0.21 to 0.79; median, 0.00). Mean plasma prekallikrein and D-dimer concentrations decreased, and Angioedema Quality of Life Questionnaire total score improved from baseline to week 105 with donidalorsen.
The 2-year interim results of this phase 2 OLE study of donidalorsen in patients with HAE demonstrated no new safety signals; donidalorsen was well tolerated. There was durable efficacy with a 96% reduction in HAE attacks.

BACKGROUND: Hereditary angioedema (HAE) is a potentially life-threatening inherited disease that causes recurrent, serious, and debilitating episodes of swelling. While evidence has improved in adult patients, data on the epidemiology and treatment of pediatric patients with HAE remain very limited. The aim of this study was to determine the incidence and prevalence of pediatric patients with HAE aged <12 years, as well as treatment patterns, co-medication, and specialties involved.
METHODS: In this retrospective study (2016-2021), the German IQVIATM pharmacy claims (LRx) database was used to analyze prescriptions of HAE-specific treatments and co-medications.
RESULTS: We found an HAE prevalence in pediatric patients aged <12 years of 2.51:100,000 and a 12-month prevalence of up to 1.02:100,000 between 2016 and 2021. Most HAE treatments were prescribed by outpatient clinics and pediatricians, with an increasing proportion of icatibant as an on-demand treatment and low rates of long-term prophylaxis (LTP). The prescription rate of analgesics as the most common co-medication decreased notably after HAE diagnosis.
CONCLUSIONS: Our findings provide insights into the epidemiology and current pediatric HAE treatment landscape in Germany. The obtained HAE prevalence in pediatric patients aged <12 years was even higher than the previously reported average of overall cohorts, whereas the LTP rate was low, which might indicate an unmet need for newer LTP treatment options in pediatric patients.

BACKGROUND: Hereditary angioedema (HAE) with C1-inhibitor deficiency (HAE-C1-INH) is characterized by recurrent, debilitating episodes of swelling. Sebetralstat, an investigational oral plasma kallikrein inhibitor, demonstrated promising efficacy for on-demand treatment of HAE-C1-INH in a phase 2 trial. We describe the multipronged approach informing the design of KONFIDENT, a phase 3 randomized, placebo-controlled, three-way crossover trial evaluating the efficacy and safety of sebetralstat in patients aged ≥12 years with HAE-C1-INH.
METHODS: To determine an optimal endpoint to measure the beginning of symptom relief in KONFIDENT, we engaged patients with HAE on clinical outcome measures and subsequently conducted analyses of phase 2 outcomes. Sample size was determined via a simulation-based approach using phase 2 data.
RESULTS: Patient interviews revealed a strong preference (71%) for the Patient Global Impression of Change (PGI-C) over other measures and indicated a rating of \"A Little Better\" as a clinically meaningful milestone. In phase 2, a rating of \"A Little Better\" demonstrated agreement with attack severity improvement and resolution on the Patient Global Impression of Severity and had better sensitivity than \"Better.\" Simulations indicated that 84 patients completing treatment would ensure at least 90% power for assessing the primary endpoint of time to beginning of symptom relief defined as a PGI-C rating of at least \"A Little Better\" for two time points in a row.
CONCLUSIONS: Patient feedback and phase 2 data support PGI-C as the primary outcome measure in the phase 3 KONFIDENT trial evaluating sebetralstat, which has the potential to be the first oral on-demand treatment for HAE-C1-INH attacks.

Symptoms of hereditary angioedema (HAE) often first occur during childhood, and HAE attacks in children can be severe and substantially affect health-related quality of life (HRQoL). However, there are no approved long-term prophylaxis treatments for children aged less than 6 years.
The SPRING Study (NCT04070326) evaluated the safety, pharmacokinetics, and efficacy of lanadelumab and HRQoL in patients aged 2 to less than 12 years.
Over 52 weeks of treatment, patients aged 2 to less than 6 years received lanadelumab 150 mg every 4 weeks (Q4W) and patients aged 6 to less than 12 years received 150 mg every 2 weeks (Q2W) but could switch to Q4W if they were attack-free for 26 weeks.
We enrolled 21 patients (aged 2 to less than 6 years: n = 4; aged 6 to less than 12 years: n = 17), 20 of whom completed the study. There were no reported serious treatment-emergent adverse events or discontinuations resulting from such events. Treatment-emergent adverse events were reported for 17 patients (81.0%). The most common TEAE was injection site pain. Overall systemic exposure was comparable for both age groups. The mean (SD) attack rate during treatment decreased by 94.8% from baseline (1.84 [1.53] to 0.08 [0.17] attacks/mo), and 16 (76.2%) patients were attack-free. The attack rate reduction in both age groups was similar during the first 26-week fixed-dosing treatment. Seven patients switched from Q2W to Q4W and remained attack-free. A large, clinically meaningful increase in the Pediatric Quality of Life Inventory Generic Core Scale Total Score and a large increase in the Pediatric Quality of Life Inventory Generic Core Scale-Family Impact Module Total Score from baseline to end of study (better HRQoL) were observed.
Findings support safety, efficacy, and improved HRQoL with lanadelumab 150 mg Q2W and Q4W regimens for the prevention of HAE attacks in patients aged 2 to less than 12 years.

Hereditary angioedema (HAE) is an autosomal dominant inherited disease in which patients suffer from local attacks primarily affecting skin and gastrointestinal tract, and sometimes even the upper respiratory tract leading to asphyxiation. Since head-to-head trials between authorized treatments are lacking, this study compares efficacy and safety of lanadelumab and intravenous plasma-derived C1-esterase inhibitor (pdC1-INH i.v.) in HAE patients on long-term prophylaxis by means of an indirect treatment comparison.
Efficacy and safety of lanadelumab against pdC1-INH i.v. were analyzed in a fully prespecified indirect comparison based on individual patient data (n = 231) from the HELP and CHANGE clinical trials. Primary and secondary efficacy endpoints were compared using a generalized linear model for count data. Confounding variables were identified a priori via systematic literature research and validated by clinical experts. Adjustment of confounders was implemented using a conditional regression model.
Lanadelumab showed a statistically significant improvement in reduction of HAE attack rates compared to pdC1-INH i.v. across multiple endpoints: Monthly attack rate of patients treated with lanadelumab was less than half compared to pdC1-INH i.v. (Rate ratio: 0.486; 95% CI: 0.253, 0.932). Monthly rate of laryngeal attacks was found to be five times lower for lanadelumab (Rate ratio: 0.2; 95% CI: 0.044, 0.915) and monthly rate of acute treated HAE attacks among lanadelumab patients was about one third of the attack rate of pdC1-INH i.v. patients (Rate ratio: 0.366; 95% CI: 0.185, 0.727).
This study contributes to current knowledge in the treatment of HAE by indicating a statistically significant reduction of HAE attacks under lanadelumab compared to pdC1-INH i.v.

The safety and efficacy of lanadelumab for the prevention of hereditary angioedema (HAE) attacks have not been studied in Japanese patients. We report outcomes from a phase 3, multicenter, open-label study (NCT04180163) of lanadelumab in Japanese patients with HAE. Japanese patients with HAE aged ≥12 years with ≥1 investigator-confirmed HAE attack during the 4-week run-in baseline period were enrolled into the study and received lanadelumab 300 mg every 2 weeks subcutaneously for 52 weeks. Dosing could be reduced to 300 mg every 4 weeks during the second 26-week treatment period if patients had well-controlled symptoms (e.g., attack-free) for 6 months. The primary efficacy endpoint was no investigator-confirmed HAE attacks (attack-free status) during days 0-182. Other outcomes included the rate of investigator-confirmed HAE attacks per month (28 days) and lanadelumab safety. Twelve patients (mean ± SD age 41.9 ± 12.4 years) were enrolled. During the first 26 weeks (days 0-182), five (41.7%) patients were attack-free. The mean ± SD HAE attack rate per month decreased by 74.0%, from 3.8 ± 2.4 during baseline to 1.2 ± 2.6 during the overall 52-week treatment period. There were no deaths or discontinuations due to treatment-emergent adverse events (TEAEs), no severe or serious TEAEs related to lanadelumab, and no positive anti-drug antibody results. The most frequent TEAEs were injection-site reactions (37 events in six patients). Most of the injection-site reaction adverse events were mild in severity. Results of this study support the findings from two global phase 3 studies for lanadelumab use as prophylactic therapy in Japanese patients with HAE.

We evaluated the safety, efficacy, and pharmacokinetics of subcutaneous weight-adjusted icatibant for the treatment of acute hereditary angioedema attacks in Japanese pediatric patients. Two patients (aged 10-13 and 6-9 years) received icatibant for a total of four attacks. Each attack was abdominal and/or cutaneous and was treated with a single icatibant injection. Mild or moderate injection-site reactions were the only adverse events reported. Time to onset of symptom relief was 0.9-1.0 h. Icatibant was rapidly absorbed, with a pharmacokinetic profile consistent with previous studies. Simulated exposure levels were consistent with non-Japanese pediatric patients. These results support the safety and efficacy of icatibant in Japanese pediatric patients.