Sustained response of recombinant human C1 esterase inhibitor for acute treatment of hereditary angioedema attacks

Ann Allergy Asthma Immunol. 2017 Apr;118(4):452-455. doi: 10.1016/j.anai.2017.01.029. Epub 2017 Mar 9.


Background: Symptoms of hereditary angioedema (HAE) attacks can recur soon after initial treatment; the durability of response for recombinant human C1 esterase inhibitor (rhC1INH) treatment is unknown.

Objective: To examine the efficacy and durability of rhC1INH for acute HAE attacks.

Methods: In this pooled post hoc analysis of 2 trials, patients with type I or II HAE (functional C1INH levels <50% of normal) and a baseline visual analog scale score of at least 50 mm were included if they had received at least 1 intravenous dose of 50 IU/kg of rhC1INH. Response was defined as symptom relief within 4 hours after treatment with persistence (≥20-mm decrease in visual analog scale scores [0 mm {"no symptoms at all"} to 100 mm {"extremely disabling"}] at 2 consecutive time points) during the 4 hours. Durability was the response without an increase of at least 20 mm in the minimum post-treatment visual analog scale score up to 24 hours. Recurrence and new attack symptoms were determined for patients with 72-hour post-treatment data.

Results: Data were analyzed for 127 patients treated with 50 IU/kg of rhC1INH in 2 studies. Most attacks (90.7%) responded within 4 hours, with differences in response rates among attack locations (61.5%-94.4%). The median time to the beginning of symptom relief was 75.0 minutes (95% confidence interval 65.0-80.0). No relapse occurred during 24 hours for attacks that initially responded. Only 7.1% of attacks were associated with symptom recurrence within 72 hours of initial rhC1INH treatment.

Conclusion: This integrated analysis supports the efficacy of rhC1INH for treatment of acute HAE across multiple attacks, with a sustained response for at least 3 days.

Trial registration: Identifiers: NCT00225147 and NCT00262301.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Complement C1 Inhibitor Protein / administration & dosage
  • Complement C1 Inhibitor Protein / therapeutic use*
  • Disease Progression
  • Female
  • Hereditary Angioedema Types I and II / drug therapy*
  • Humans
  • Male
  • Middle Aged
  • Recombinant Proteins / administration & dosage
  • Recombinant Proteins / therapeutic use*
  • Recurrence
  • Time-to-Treatment
  • Treatment Outcome
  • Young Adult


  • Complement C1 Inhibitor Protein
  • Recombinant Proteins

Associated data