title: Omalizumab pretreatment decreases acute reactions after rush immunotherapy for ragweed-induced seasonal allergic rhinitis.
abstract: BACKGROUND
  Rush immunotherapy (RIT) presents an attractive alternative to standard immunotherapy. However, RIT carries a much greater risk of acute allergic reactions, including anaphylaxis.
  
  
  OBJECTIVE
  We hypothesized that omalizumab, a humanized monoclonal anti-IgE antibody, would be effective in enhancing both safety and efficacy of RIT.
  
  
  METHODS
  Adult patients with ragweed allergic rhinitis were enrolled in a 3-center, 4-arm, double-blind, parallel-group, placebo-controlled trial. Patients received either 9 weeks of omalizumab (0.016 mg/kg/IgE [IU/mL]/mo) or placebo, followed by 1-day rush (maximal dose 1.2-4.0 mug Amb a 1) or placebo immunotherapy, then 12 weeks of omalizumab or placebo plus immunotherapy.
  
  
  RESULTS
  Of the 159 patients enrolled, 123 completed all treatments. Ragweed-specific IgG levels increased >11-fold in immunotherapy patients, and free IgE levels declined >10-fold in omalizumab patients. Patients receiving omalizumab plus immunotherapy had fewer adverse events than those receiving immunotherapy alone. Post hoc analysis of groups receiving immunotherapy demonstrated that addition of omalizumab resulted in a 5-fold decrease in risk of anaphylaxis caused by RIT (odds ratio, 0.17; P = .026). On an intent-to-treat basis, patients receiving both omalizumab and immunotherapy showed a significant improvement in severity scores during the ragweed season compared with those receiving immunotherapy alone (0.69 vs 0.86; P = .044).
  
  
  CONCLUSIONS
  Omalizumab pretreatment enhances the safety of RIT for ragweed allergic rhinitis. Furthermore, combined therapy with omalizumab and allergen immunotherapy may be an effective strategy to permit more rapid and higher doses of allergen immunotherapy to be given more safely and with greater efficacy to patients with allergic diseases.
authors.affiliation: Creighton University School of Medicine, Omaha, NE 68131, USA. tbcasale@creighton.edu
authors.forename: Thomas B
authors.initials: TB
authors.lastname: Casale
authors.forename: William W
authors.initials: WW
authors.lastname: Busse
authors.forename: Joel N
authors.initials: JN
authors.lastname: Kline
authors.forename: Zuhair K
authors.initials: ZK
authors.lastname: Ballas
authors.forename: Mark H
authors.initials: MH
authors.lastname: Moss
authors.forename: Robert G
authors.initials: RG
authors.lastname: Townley
authors.forename: Masoud
authors.initials: M
authors.lastname: Mokhtarani
authors.forename: Vicki
authors.initials: V
authors.lastname: Seyfert-Margolis
authors.forename: Adam
authors.initials: A
authors.lastname: Asare
authors.forename: Kirk
authors.initials: K
authors.lastname: Bateman
authors.forename: Yamo
authors.initials: Y
authors.lastname: Deniz
mesh_terms: D000293:Adolescent; D000328:Adult; D031164:Ambrosia / Q000276:immunology*; D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal / Q000627:therapeutic use*; D061067:Antibodies, Monoclonal, Humanized; D003888:Desensitization, Immunologic / Q000009:adverse effects*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D007073:Immunoglobulin E / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008875:Middle Aged; D000069444:Omalizumab; D006255:Rhinitis, Allergic, Seasonal / Q000276:immunology / Q000628:therapy*
chemical_list: D000888:Antibodies, Anti-Idiotypic; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D007074:Immunoglobulin G; D000069444:Omalizumab; D007073:Immunoglobulin E