title: Sustained response of recombinant human C1 esterase inhibitor for acute treatment of hereditary angioedema attacks.
abstract: 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.
  
  
  
  To examine the efficacy and durability of rhC1INH for acute HAE attacks.
  
  
  
  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.
  
  
  
  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.
  
  
  
  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.
  
  
  
  ClinicalTrials.gov Identifiers: NCT00225147 and NCT00262301.
authors.affiliation: Division of Immunology, Allergy and Rheumatology, Department of Internal Medicine, University of Cincinnati College of Medicine, Cincinnati, Ohio. Electronic address: bernstja@ucmail.uc.edu.
authors.forename: Jonathan A
authors.initials: JA
authors.lastname: Bernstein
authors.affiliation: Department of Clinical Research and Medical Affairs, Pharming Healthcare Inc., Berkeley Heights, New Jersey.
authors.forename: Anurag
authors.initials: A
authors.lastname: Relan
authors.affiliation: Department of Clinical Research and Medical Affairs, Pharming Healthcare Inc., Berkeley Heights, New Jersey.
authors.forename: Joseph R
authors.initials: JR
authors.lastname: Harper
authors.affiliation: Division of Rheumatology, Allergy and Immunology, Department of Medicine, University of California-San Diego, La Jolla, California.
authors.forename: Marc
authors.initials: M
authors.lastname: Riedl
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D050718:Complement C1 Inhibitor Protein / Q000008:administration & dosage / Q000627:therapeutic use*; D018450:Disease Progression; D005260:Female; D056829:Hereditary Angioedema Types I and II / Q000188:drug therapy*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000627:therapeutic use*; D012008:Recurrence; D061665:Time-to-Treatment; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D050718:Complement C1 Inhibitor Protein; D011994:Recombinant Proteins