title: Efficacy and safety of recombinant C1 inhibitor for the treatment of hereditary angioedema attacks: a North American open-label study.
abstract: BACKGROUND
  The efficacy of recombinant human C1 inhibitor (rhC1INH) for the treatment of patients with acute hereditary angioedema (HAE) attacks has been demonstrated in 2 randomized, double-blind, placebo-controlled studies.
  
  
  OBJECTIVE
  To assess the safety and efficacy of rhC1INH for repeated treatment of acute attacks of HAE.
  
  
  METHODS
  In this open-label extension study, patients with eligible HAE attacks were treated with an intravenous 50-U/kg dose of rhC1INH with an option for an additional dose of 50 U/kg based on clinical response. Time to beginning of relief was assessed by patients using a 100-mm visual analogue scale (VAS). Safety evaluation was based on the clinical laboratory results and adverse events.
  
  
  RESULTS
  Sixty-two patients were treated for 168 attacks (range, 1-8 attacks per patient). A total of 90% of the attacks were treated with a single 50-U/kg dose of rhC1INH. Median times to beginning of symptom relief for the first 5 attacks were 37 to 67 minutes. More than 90% of attacks responded within 4 hours after treatment with rhC1INH. There was no requirement for increased dosing with successive treatments. Thirty-nine patients (63%) reported at least 1 treatment-emergent adverse event, with most events rated mild to moderate. Seven severe treatment-emergent adverse events were reported, and all were considered to be unrelated to treatment with rhC1INH.
  
  
  CONCLUSIONS
  The results of this open-label extension support continued efficacy of rhC1INH after repeated treatments for subsequent HAE attacks. There was no increase in adverse event reporting after repeated exposure to rhC1INH.
authors.affiliation: University of California Los Angeles, David Geffen School of Medicine, Los Angeles, California 90095-1680, USA. mriedl@mednet.ucla.edu
authors.forename: Marc A
authors.initials: MA
authors.lastname: Riedl
authors.forename: Robyn J
authors.initials: RJ
authors.lastname: Levy
authors.forename: Daniel
authors.initials: D
authors.lastname: Suez
authors.forename: Richard F
authors.initials: RF
authors.lastname: Lockey
authors.forename: James W
authors.initials: JW
authors.lastname: Baker
authors.forename: Anurag
authors.initials: A
authors.lastname: Relan
authors.forename: Bruce L
authors.initials: BL
authors.lastname: Zuraw
mesh_terms: D000293:Adolescent; D000328:Adult; D054179:Angioedemas, Hereditary / Q000188:drug therapy* / Q000276:immunology; D050718:Complement C1 Inhibitor Protein / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009656:North America; D011994:Recombinant Proteins / Q000008:administration & dosage / Q000009:adverse effects* / Q000627:therapeutic use*; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D050718:Complement C1 Inhibitor Protein; D011994:Recombinant Proteins