 ICAC-01 also includes a mechanistic sub-study ICAC-02. Its primary objective is to determine whether highly sensitized, compared to weakly sensitized asthmatic subjects have more severe asthma, as defined by the levels at randomization to the completion of ICAC-01. To address the primary objective of ICAC-02, the study will include all the participants enrolled in ICAC-01 with dust mite-, cockroach- andor alternaria-specific IgE levels within certain parameters. 