A Single-center Retrospective Study on the Clinical Characteristics of Patients with Hereditary Angioedema and the Therapeutic Effect of Lanadelumab

Background: Hereditary angioedema (HAE) is a rare monogenic disease, and there are few reports on the clinical characteristics of HAE, particularly the drug efficacy, in China. The objective of this study is to gain insight into the clinical characteristics of Chinese HAE patients, and the efficacy and safety of prophylactic treatment with Lanadelumab. Results: The cohort included 22 patients with a median age of 35.0 years (IQR: 27.0-48.3 years). The male-to-female ratio was 1:1.75. The median age at onset was 15.5 years (IQR: 10.0-21.3 years), with a median diagnostic delay of 18.5 years. Of the cohort, 18 patients (81.8%) had Type I HAE, while 4 patients (18.2%) had Type II HAE. The average monthly frequency of attacks was 1.3. 10 patients (45.5%) experienced onset following minor trauma/local bumps/pressure/heat exposure, which was the most common precipitating factor; 7 patients (31.8%) had spontaneous onset without apparent precipitating factors. A family history was reported in 16 patients (72.7%). 6 patients (27.3%) had concomitant diseases involving various positive autoantibodies or confirmed autoimmune diseases. 11 patients (50.0%) in this cohort were either currently receiving or had previously received Lanadelumab treatment, with a median treatment duration of 7 months (IQR: 3-10 months). 9 patients reached the steady state period of treatment (>70 days). 8 patients experienced no edema attack during treatment. There was a significant reduction in the frequency of attacks and a significant improvement in quality of life by Day 28 (D28) post-treatment, with a decrease of 91.5%in the average monthly frequency of attacks. The average monthly frequency of attacks decreased by 94.6% and 96.2% on D70 and at the time of the last injection, respectively, with no life-threatening laryngeal edema attacks. Only 5 patients (45.5%) had local adverse reactions during treatment, and no severe adverse reactions were reported. Conclusion: (1) The median age at onset, diagnostic delay, and precipitating factors in this cohort were consistent with previously reported data in domestic studies. However, the proportion of Type II patients was higher compared to prior domestic reports; notably, this cohort identified a high proportion (27.3%) of patients with positive autoantibodies or confirmed autoimmune diseases for the first time in China. (2) After treatment with Lanadelumab, patients experienced significant improvements in symptoms, quality of life, and anxiety/depression levels; Symptom control was achieved by D28 prior to the drug steady state period and was maintained throughout the drug steady state period (i.e., 70 days of dosing, D70) and the entire treatment period. No serious adverse reactions were observed during the treatment, indicating a high safety profile for the medication. Trial registration: National National Health security information platform medical research registration and filing information system of China, MR-31-24-044427. Registered 25 November 2024, https://www.medicalresearch.org.cn/clinicalResearch/researchInfo?id=1390c58c-5ada-41ce-bea3-ce83e5d8844b