title: Analysis of characteristics associated with reinjection of icatibant: Results from the icatibant outcome survey.
abstract: OBJECTIVE
  Phase 3 icatibant trials showed that most hereditary angioedema (HAE) (C1 inhibitor deficiency) acute attacks were treated successfully with one injection of icatibant, a selective bradykinin B2 receptor antagonist. We conducted a post hoc analysis of icatibant reinjection for HAE type I and II attacks in a real-world setting by using data from the Icatibant Outcome Survey, an ongoing observational study that monitors the safety and effectiveness of icatibant treatment.
  
  
  METHODS
  Descriptive retrospective analyses of icatibant reinjection were performed on Icatibant Outcome Survey data (February 2008 to December 2012). New attacks were defined as the onset of new symptoms after full resolution of the previous attack. Potential associations between the patient and attack characteristics and reinjection were explored by using logistic regression analysis.
  
  
  RESULTS
  Icatibant was administered for 652 attacks in 170 patients with HAE type I or II. Most attacks (89.1%) were treated with a single icatibant injection. For attacks that required two or three injections, the second injection was given a median of 11.0 hours after the first injection, with 90.4% of second injections administered ≥6 hours after the first injection. Time to resolution and attack duration were significantly longer for two or three injections versus one icatibant injection (p < 0.0001 and p < 0.05, respectively). Multivariate logistic regression analysis identified sex, attack severity, and laryngeal attacks as significantly correlated with reinjection (all p ≤ 0.05). These factors did not remain predictors for reinjection when two outlier patients with distinct patterns of icatibant use were excluded.
  
  
  CONCLUSIONS
  In this real-world setting, most HAE attacks resolved with one icatibant injection. There was no distinct profile for patients or attacks that required reinjection when outliers with substantially different patterns of use were excluded. Because new attacks were not distinguished from the recurrence of symptoms, reinjection rates may be slightly higher than shown here. Clinical trial identifier: NCT01034969.
authors: Department of Immunology, Barts Health NHS Trust, London, UK.
authors: Hilary J
authors: HJ
authors: Longhurst
authors: Werner
authors: W
authors: Aberer
authors: Laurence
authors: L
authors: Bouillet
authors: Teresa
authors: T
authors: Caballero
authors: Vincent
authors: V
authors: Fabien
authors: Andrea
authors: A
authors: Zanichelli
authors: Marcus
authors: M
authors: Maurer
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D055815:Young Adult; D001920:Bradykinin / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000494:pharmacology; D065094:Bradykinin B2 Receptor Antagonists / Q000008:administration & dosage / Q000494:pharmacology; D004334:Drug Administration Schedule; D056829:Hereditary Angioedema Types I and II / Q000175:diagnosis / Q000188:drug therapy; D007267:Injections; D043782:Receptor, Bradykinin B2 / Q000378:metabolism; D012189:Retrospective Studies; D011795:Surveys and Questionnaires; D016896:Treatment Outcome
chemical_list: D001920:Bradykinin; D065094:Bradykinin B2 Receptor Antagonists; C065679:icatibant; D043782:Receptor, Bradykinin B2