Clinical Characteristics and Safety of Plasma-Derived C1-Inhibitor Therapy in Children and Adolescents with Hereditary Angioedema-A Long-Term Survey

BACKGROUND: Plasma-derived C1-inhibitor (pdC1-INH) is a first-line therapy for hereditary angioedema (HAE) with C1-inhibitor deficiency (C1-INH-HAE) in pediatric patients. OBJECTIVE: We intended to study the clinical characteristics and safety of treatment with pdC1-INH in this population. METHODS: In the prospective, long-term survey, real-world data on pdC1-INH (Berinert, CSL Behring) use in pediatric patients, diagnosed and followed up at our Angioedema Reference Center, were analyzed for the period from 1986 to 2018. RESULTS: A total of 70 pediatric patients (31 boys and 39 girls) experienced a total of 3009 HAE attacks. The most common location of HAE attacks was subcutaneous. HAE attacks of any location were more frequent in girls versus boys, except for genital edema. Among the 70 patients, 37 received pdC1-INH for 456 HAE attacks, or as prophylaxis (69 vials). On average, 14.2 vials were administered per patient. The distribution of pdC1-INH use in the different age groups was as follows: no use (0-1 years), 0.11 vials/year (1-3 years), 0.7 vials/year (3-6 years), 1.26 vials/year (6-12 years), and 1.28 vials/year (12-18 years). No systemic allergic reactions, viral transmission, development of anti-C1-INH antibodies, or thromboembolic events occurred in relation to treatment with this drug. CONCLUSION: We confirmed that the clinical manifestations and the use of pdC1-INH are different in the various age groups of pediatric patients with C1-INH-HAE. Our long-term survey shows that the use of pdC1-INH is safe in this patient population. (C) 2020 The Authors. Published by Elsevier Inc. on behalf of the American Academy of Allergy, Asthma & Immunology.