Preventative Omalizumab or Step-up Therapy for Severe Fall Exacerbations

Inclusion Criteria : * Combined body weight (as measured at the screening visit) and total serum IgE level (as measured within 3 months of the screening visit) suitable for omalizumab (Xolair®) dosing; * A diagnosis of asthma by a clinician made more than 1 year prior to recruitment; participants who received an asthma diagnosis by a clinician less than 1 year prior to recruitment must report that their respiratory symptoms were present for more than 1 year prior to recruitment; * Having a requirement for at least 100 mcg fluticasone 100 mcg twice a day or equivalent at the Assumption of Care Visit AND who meet at least one of the following criteria: i. ≥1 asthma-related exacerbations, separated by at least two weeks, requiring treatment with a systemic corticosteroid course in the previous 12 months ii. ≥1 asthma-related overnight hospitalizations in the past 12 months. * A positive prick skin-test to at least one perennial allergen (i.e. dust mite, cockroach, mold, cat, dog, rat, mouse) documented at the screening visit or at a ICAC study visit within 12 months of the screening visit; * Primary place of residence is in one of the pre-selected recruitment census tracts; * Able to perform spirometry; * Parent or legal guardian is willing to sign the written informed consent (age appropriate) prior to initiation of any study procedure; * Willing to sign the assent form, if age appropriate; * A history of chickenpox or receipt of the chickenpox vaccine; * Insurance which co…