Recombinant human C1 esterase inhibitor treatment for hereditary angioedema attacks in children

Pediatr Allergy Immunol. 2019 Aug;30(5):562-568. doi: 10.1111/pai.13065. Epub 2019 May 29.


Background: Attacks of hereditary angioedema (HAE) due to C1 esterase inhibitor deficiency (C1-INH-HAE) usually begin during childhood or adolescence. However, limited data are available regarding indications and modalities of treatment of children. This study evaluated recombinant human C1-INH (rhC1-INH) for HAE attacks in children.

Methods: This open-label, phase 2 study included children aged 2-13 years with C1-INH-HAE. Eligible HAE attacks were treated intravenously with rhC1-INH 50 IU/kg body weight (maximum, 4200 IU). The primary end-point was time to beginning of symptom relief (TOSR; ≥20 mm decrease from baseline in visual analog scale [VAS] score, persisting for two consecutive assessments); secondary end-point was time to minimal symptoms (TTMS; <20 mm VAS score for all anatomic locations).

Results: Twenty children (aged 5-14 years; 73 HAE attacks) were treated with rhC1-INH. Seventy (95.9%) of the attacks were treated with a single dose of rhC1-INH. Seven (35.0%) children were treated for four or more attacks. Overall, median TOSR was 60.0 minutes (95% confidence interval [CI], 60.0-65.0); data were consistent across attacks. Median TTMS was 122.5 minutes (95% CI, 120.0-126.0); data were consistent across attacks. No children withdrew from the study due to adverse events. No treatment-related serious adverse events or hypersensitivity reactions were reported; no neutralizing antibodies were detected.

Conclusions: Recombinant human C1-INH was efficacious, safe, and well tolerated in children. Data support use of the same dosing regimen for HAE attacks in children (50 IU/kg; up to 4200 IU, followed by an additional dose, if needed) as is currently recommended for adolescents and adults.

Keywords: angioedema; child; complement C1 inactivator proteins; complement C1s; hereditary; hereditary angioedema type I and type II; recombinant proteins.

Publication types

  • Clinical Trial, Phase II
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Intravenous
  • Adolescent
  • Angioedemas, Hereditary / drug therapy*
  • Body Weight
  • Child
  • Child, Preschool
  • Clinical Protocols
  • Complement C1 Inhibitor Protein / therapeutic use*
  • Drug Dosage Calculations
  • Female
  • Humans
  • Male
  • Recombinant Proteins / therapeutic use*
  • Treatment Outcome


  • Complement C1 Inhibitor Protein
  • Recombinant Proteins