Inclusion Criteria:
- Total IgE ≥30 IU (historical values obtained within 3 months of screening visit will be accepted). If historic result not available, to be obtained at screening visit.
- Diagnosis of asthma for at least 12 months prior to screening visit date, or symptoms compatible with asthma for at least 12 months if diagnosis made within 12 months of screening visit
- Documented sensitivity to one or more perennial aeroallergens as evidenced by a positive skin prick test or in-vitro specific IgE test for dust mites, cat dander, dog dander or cockroach within the preceding one year of the screening visit
- Prescribed inhaled corticosteroid for at least 3 months prior to screening (A) and having evidence of inadequately controlled disease either with at least one from list (B) OR history of asthma-related exacerbations as defined in (C). [e.g., A and (B or C)]
A. Fluticasone DPI > 200 mcg/day or equivalent ex-valve dose ICS, or if ≤ 200 mcg fluticasone DPI or equivalent plus another daily controller medication (i.e. LABA, leukotriene antagonist or theophylline)
B. At least one of the following in the preceding 4 weeks prior to the screening visit:
- on average asthma symptoms > 2 days/week or multiple times in a day on ≤ 2 days/week
- nighttime awakenings ≥ 2 times/month due to asthma symptoms
- use of SABAs > 2 times/week on average
- some limitation in activity due to asthma
- on spirometric evaluation, FEV1 ≤ 80% of predicted, FEV1/FVC ≤ 80%, or peak expiratory flow rate ≤ 80% of personal best
C. Minimum of 2 asthma exacerbations requiring oral corticosteroid bursts in the 12 months previous to the screening visit
Exclusion Criteria:
- Subjects currently enrolled in a clinical study of a therapeutic agent or biologic agent or who participated in a clinical study of a therapeutic agent within 30 days of Visit 1 or a biologic agent within 120 days of Visit 1
- Subjects with a history of prior use of omalizumab
- Subjects with a severe medical condition that in the view of the investigator prohibits participation in the study by either impairment in the ability to answer questions or follow instructions (e.g., severe neurological or developmental disorder)
- Subjects with serious respiratory-related medical conditions other than allergic asthma such as, but not limited to, allergic bronchopulmonary aspergillosis, cystic fibrosis or bronchiectasis
- Subjects with elevated serum IgE levels for reasons other than allergy such as, but not limited to, parasitic infections, hyperimmunoglobulin E syndrome, and Wiskott-Aldrich Syndrome
Other protocol-defined inclusion/exclusion criteria may apply