Section : Conference Notes

Omalizumab (Xolair) for Urticaria Treatment

Omalizumab (Xolair):

  • recombinant humanized monoclonal antibody that binds to the free Immunoglobin IgE (produced byB lymphocytes), more specifically on the C3 domain of the IgE heavy chain complete, it block free IgE.
  • Unlike ordinary anti-IgE antibodies, it does not bind to IgE that is already bound by the high affinity IgE receptor (FcεRI) on the surface of mast cells, basophils, and antigen-presenting dendritic cells.
  • It also acts in many different ways
  • Indications
    • moderate-to-severe asthma
    • chronic urticaria unresponsive to antihistamines
    • Note: studies suggest that physical urticaria responds to omalizumab
  • monomeric murine IgE anti-bodies have been seen in atopic dermatitis
  • Dosing
    • asthma = weight dependent
    • chronic urticaria 300mg subcutaneous injection
  • study done in Germany which showed the following response rates:
    • “hive free”:
      • placebo group: 10% of untreated patients
      • 75mg dosage group: 18% of treated patients
      • 150mg dosage group: 23 % of treated patients
      • 300mg dosage group: 53% of treated patients
    • “itch and hive free”:
      • placebo group: 5% of untreated patients
      • 75mg dosage group: 16% of treated patients
      • 150mg dosage group: 22 % of treated patients
      • 300mg dosage group: 43% of treated patients
    • no safety effects reported: recommendation of surveillance one hour following the injection
  • Remarks:
    • studies show that the 300mg dosage effect is similar to 600mg and of course far superior to placebo, 75mg or 150mg
    • the dosing schedule is unclear but in practice, it is administered monthly

Contributors

Dr Christophe Hsu – dermatologist. Geneva, Switzerland

S002 – Jackson JM et al. Systemic Therapies for Dermatologists: a Comprehensive Review and Update. AAD 2015 Annual Meeting, San Francisco CA – United States