title: New treatment options for acute edema attacks caused by hereditary angioedema.
abstract: OBJECTIVE
  New treatment options for acute edema attacks caused by hereditary angioedema (HAE) are reviewed.
  
  
  CONCLUSIONS
  HAE is characterized by mutations in the C1 inhibitor gene leading to either a reduced expression of C1 inhibitor in the plasma or expression of a functionally impaired C1 inhibitor. HAE is classified into two major types based on the cause of the C1 inhibitor deficiency. Type I HAE is defined by a reduced expression of C1 inhibitor in the plasma, whereas type II HAE is characterized by the expression of a dysfunctional C1 inhibitor protein. Clinical data were reviewed for C1 inhibitor, ecallantide, and icatibant in the treatment of acute edema attacks caused by HAE. C1 inhibitor leads to a faster onset of edema relief and is effective in decreasing the duration of edema. Dosing strategies include fixed dosing and weight-based dosing. Optimal dosing strategies have not been established, but fixed dosing (500-1000 units) or 20 units/kg has been effective in clinical trials and reports. No comparative trials suggest that one strategy is superior to another; however, the approved labeling for acute treatment is based on weight. Ecallantide is also efficacious for treating acute episodes; however, the available evidence is limited to a single published trial. Icatibant has shown variable effects in two trials with placebo and active controls.
  
  
  CONCLUSIONS
  In patients with HAE, most edema episodes only involve the skin and gastrointestinal tract, though airway obstruction caused by laryngeal angioedema is the most common cause of death. I.V. C1 inhibitor should be considered first-line treatment for acute edema attacks because of its fast onset of action and effectiveness, though it is not clear whether fixed or weight-based dosing is preferred. Ecallantide can be considered as a second-line treatment option.
authors: South University School of Pharmacy, 709 Mall Boulevard, Savannah, GA 31406, USA. mcthomas@southuniversity.edu
authors: Michael C
authors: MC
authors: Thomas
authors: Samit
authors: S
authors: Shah
mesh_terms: D000208:Acute Disease; D054179:Angioedemas, Hereditary / Q000188:drug therapy* / Q000453:epidemiology / Q000503:physiopathology; D003174:Complement C1 Inactivator Proteins / Q000627:therapeutic use; D050718:Complement C1 Inhibitor Protein / Q000008:administration & dosage / Q000627:therapeutic use*; D051056:Complement Inactivating Agents / Q000008:administration & dosage / Q000627:therapeutic use*; D004487:Edema / Q000188:drug therapy* / Q000209:etiology; D006801:Humans; D010455:Peptides / Q000008:administration & dosage / Q000627:therapeutic use
chemical_list: D003174:Complement C1 Inactivator Proteins; D050718:Complement C1 Inhibitor Protein; D051056:Complement Inactivating Agents; D010455:Peptides; C469952:SERPING1 protein, human; C511194:ecallantide