Safety and tolerability of omalizumab

Clin Exp Allergy. 2009 Jun;39(6):788-97. doi: 10.1111/j.1365-2222.2009.03214.x. Epub 2009 Mar 17.


Background: Omalizumab (Xolair) is a recombinant humanized monoclonal anti-IgE antibody with proven efficacy in patients with moderate-to-severe and severe persistent allergic (IgE-mediated) asthma.

Objective: To review clinical study data to assess the safety profile of omalizumab.

Methods: We analysed the safety of omalizumab using data from completed clinical studies (up to 1 year) involving more than 7500 patients with asthma, rhinitis or related conditions and up to 4 years in one study of patients with severe allergic asthma, as well as post-marketing safety data. Analysis focuses on the risk of immune-system effects, hypersensitivity reactions, malignant neoplasia, parasitic infections and thrombocytopenia.

Results: Omalizumab exhibited a good safety and tolerability profile that was maintained up to 4 years in one study. The incidence of anaphylaxis was 0.14% in omalizumab-treated patients and 0.07% in control patients. No omalizumab-treated patient developed measurable anti-omalizumab antibodies. Post-marketing, based on estimated exposure of 57,300 patients (June 2003-December 2006), the frequency of anaphylaxis attributed to omalizumab use was estimated to be at least 0.2% of patients. Current clinical trial data do not support an increased risk of malignant neoplasia or thrombocytopenia with omalizumab.

Conclusion: Data indicate that the proven efficacy of add-on omalizumab in patients with moderate-to-severe or severe allergic asthma is accompanied by a favourable safety and tolerability profile.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Anaphylaxis / immunology
  • Anti-Asthmatic Agents / adverse effects
  • Anti-Asthmatic Agents / therapeutic use*
  • Antibodies, Anti-Idiotypic / adverse effects
  • Antibodies, Anti-Idiotypic / therapeutic use*
  • Antibodies, Monoclonal / adverse effects
  • Antibodies, Monoclonal / therapeutic use*
  • Antibodies, Monoclonal, Humanized
  • Asthma / drug therapy*
  • Churg-Strauss Syndrome / immunology
  • Clinical Trials as Topic
  • Humans
  • Infections / immunology
  • Neoplasms / immunology
  • Omalizumab
  • Thrombocytopenia / immunology


  • Anti-Asthmatic Agents
  • Antibodies, Anti-Idiotypic
  • Antibodies, Monoclonal
  • Antibodies, Monoclonal, Humanized
  • anti-IgE antibodies
  • Omalizumab