Omalizumab inhibits allergen challenge-induced nasal response.

Elevated serum levels of antigen-specific immunoglobulin (Ig)E are often associated with allergic respiratory diseases. This parallel-group, randomised, double-blind, placebo-controlled trial was designed to study the influence of omalizumab on the early nasal response to allergen challenge reflected by symptom score and inflammatory marker levels in nasal lavage fluid (NAL). A total of 23 patients with allergic rhinitis took part in the study, 11 were given placebo and omalizumab was administered subcutaneously in 12. Omalizumab or placebo were given at 2- or 4-week intervals based on a patient's body weight and IgE levels to a total dose of 0.016 mg x kg(-1) x IgE(-1) (IU x mL(-1)) every 4 weeks. Compared to placebo, 16 weeks of treatment with omalizumab significantly inhibited allergen challenge-induced nasal symptoms (median symptom score 7.0-0.5 versus 7.0-7.0) and inhibited the increase of human serum albumin (median 15.3-0.12 mg x mL(-1) versus 8.2-19.7 mg x mL(-1)) in the NAL after allergen challenge. Treatment with omalizumab induced a significant decrease in tumour necrosis factor-alpha levels in basal NAL, but no change was seen for histamine. These results indicate that subcutaneously administered monoclonal anti-immunoglobulin-E antibody, omalizumab, inhibits the nasal responses to allergen challenge of patients with allergic rhinitis. Omalizumab may provide a new strategy for the treatment of allergic rhinitis.