The purpose of this trial is to compare the efficacy of 4 to 5 months of three treatments - omalizumab, corticosteroid therapy boost, and placebo - in reducing fall exacerbations in inner-city children and adolescents with allergic persistent asthma when initiated approximately 4 -6 weeks prior to the start of the first day of each participant's school year.

While the increase in the prevalence of asthma has abated, levels of asthma morbidity and mortality remain near record highs. An asthma exacerbation is a major factor contributing to morbidity, and even mortality in patients with asthma. Although current approaches to treatment have reduced these risks, asthma exacerbations are major problems for inner-city patients and their families, and prevention of these events continues to be a significant challenge. In children with asthma, there are predictable seasonal epidemics of exacerbations, especially during the fall season, otherwise known as the "September epidemic."