- Prohibited medications: Subjects receiving any of the following: OCS: Subject requires an oral corticosteroid dose of >50 mg/day prednisolone/prednisone in the 4-week period prior to Baseline (Visit 2); Intravenous or SC corticosteroids in the 4-week period prior to Baseline (Visit 2); Omalizumab within 130 days prior to Screening (Visit 1); Cyclophosphamide: oral CYC within 2 weeks prior to Baseline (Visit 2) and IV CYC within 3 weeks prior to Baseline (Visit 2), if their total WBC is >=4x10^9/Liter (measured using the local laboratory if necessary); Rituximab within 12 months prior to Screening (Visit 1); in addition, the subject must have shown recovery of peripheral B-cell count to within the normal range; IV or SC immunoglobulin within 6 months prior to Screening (Visit 1); Interferon-α within 6 months prior to Screening (Visit 1); Anti-TNF therapy within 12 weeks prior to Screening (Visit 1); Anti-CD52 (alemtuzumab) within 6 months prior to Screening (Visit 1).