Double blind protocol treatment of 2/3 of the patients with omalizumab and 1/3 placebo administer for 4 months. Patients selected for the study must have both aspirin exacerbated respiratory disease and allergic asthma and rhinitis. They must also have completed aspirin desensitization and be taking aspirin on a daily basis for the treatment of AERD.

60 patients with Aspirin Exacerbated respiratory Disease will be screened to determine if they also have allergic respiratory tract disease as a co-morbid complication. This will involve history, allergy skin tests and a serum IgE level. They must also have been desensitized to aspirin and be taking aspirin 325 or 650 mg morning and night.

40/60 patients will receive omalizumab injections every month for the next 4 months and the other 20 patients, via a random program, will receive placebo injections.

Monthly visits with the nurse co-ordinator will involve the following assessments: daily symptom scores, daily use of medications (particularly prednisone and rescue albuterol inhalers), lung function tests, nasal breathing test, measurement of smell and quality of life scores pre and post study.

Inclusion Criteria:

aspirin exacerbated respiratory disease and allergic asthma

Exclusion Criteria:

• pregnant females,starting immunotherapy in the past 3 months, prior treatment with Xolair, negative allergy skin tests,unable to participate in lung function tests, unable to complete data forms,low platelets, serum IGE greater than 700 iu,cancer,another uncontrolled medical condition, unacceptable concomitant medication, under the age of 18 years.