A Safety Study of Xolair (Omalizumab) in Patients With Chronic Idiopathic Urticaria (CIU) Who Remain Symptomatic Despite Treatment With H1 Antihistamines, H2 Blockers, and/or Leukotriene Receptor Antagonists

The weekly itch severity score is the sum of the daily itch severity scores over 7 days and ranges from 0 to 21. The daily itch severity score is the average of the morning and evening scores on a scale of 0 (none) to 3 (severe). The Baseline weekly itch severity score is the sum of the daily itch severity scores over the 7 days prior to the first treatment. A higher itch severity score indicates more severe itching. A negative change score indicates improvement.

The UAS7 is the sum of the daily urticarial activity scores over 7 days and ranges from 0 to 42. The daily urticarial activity score is the average of the morning and evening urticarial activity scores and ranges from 0 to 6. The urticarial activity score is the sum of ratings on a scale of 0 to 3 (0=none to 3=intense/severe) for (1) the number of wheals (hives) and (2) itch intensity over the previous 12 hours, ranges from 0 to 6, and is measured twice daily (morning and evening). The Baseline score is the sum of the daily urticarial activity scores over the 7 days prior to the first treatment. A higher urticarial activity score indicates more urticaria activity. A negative change score indicates improvement.

The weekly hives score is the sum of the daily hives scores over 7 days and ranges from 0 to 21. The number of hives is measured twice daily (morning and evening) on a scale of 0 (none) to 3 (> 12 hives per 12 hours). The daily hives score is the average of the morning and evening scores. The Baseline score is the sum of the daily hives scores over the 7 days prior to the first treatment. A higher score indicates more hives. A negative change score indicates improvement.

The time to the MID response is the number of weeks from the start of treatment (Baseline) until the time point at which the first MID response occurs. The MID response is defined as a reduction ≥ 5 points from Baseline in the weekly itch severity score. The weekly itch severity score is the sum of the daily itch severity scores over 7 days and ranges from 0 to 21. The daily itch severity score is the average of the morning and evening scores on a scale of 0 (none) to 3 (severe). The Baseline weekly itch severity score is the sum of the daily itch severity scores over the 7 days prior to the first treatment. A higher itch severity score indicates more severe itching.

The UAS7 is the sum of the daily urticarial activity scores over 7 days and ranges from 0 to 42. The daily urticarial activity score is the average of the morning and evening urticarial activity scores and ranges from 0 to 6. The urticarial activity score is the sum of ratings on a scale of 0 to 3 (0=none to 3=intense/severe) for (1) the number of wheals (hives) and (2) itch intensity over the previous 12 hours, ranges from 0 to 6, and is measured twice daily (morning and evening). The Baseline score is the sum of the daily urticarial activity scores over the 7 days prior to the first treatment. A higher urticarial activity score indicates more urticaria activity.

The percentage of participants with an itch severity score at 12 Weeks at least 5 points lower than at Baseline. The weekly itch severity score is the sum of the daily itch severity scores over 7 days and ranges from 0 to 21. The daily itch severity score is the average of the morning and evening scores on a scale of 0 (none) to 3 (severe). The Baseline weekly itch severity score is the sum of the daily itch severity scores over the 7 days prior to the first treatment. A higher itch severity score indicates more severe itching.

The weekly size of the largest hive score is the sum of the daily size of the largest hive scores over 7 days and ranges from 0 to 21. The daily size of the largest hive score is assessed twice daily (morning and evening) on a scale of 0 (none) to 3 (> 2.5 cm). The daily size of the largest hive score is the average of the morning and evening scores. The Baseline weekly size of the largest hive score is calculated over the 7 days prior to the first treatment. A higher score indicates larger hives. A negative change score indicates a reduction in hive size.

The DLQI is a 10-item dermatology-specific health-related quality of life measure. Patients rated their dermatology symptoms as well as the impact of their skin condition on various aspects of their lives on a scale of 0 (Not at all) to 3 (Very much). The overall DLQI is the sum of the responses to the 10 items and ranges from 0 to 30. A lower score indicates a better quality of life. A negative change score indicates improvement.

The percentage of angioedema-free days from Weeks 4 to 12 was defined as the number of days for which a patient responded "No" to the angioedema question in the daily diary divided by the total number of days with a non-missing diary entry, starting at the Week 4 visit and ending the day prior to the Week 12 visit.

A complete responder was defined as a participant with a UAS7 score = 0 at Week 12. The UAS7 is the sum of the daily urticarial activity scores over 7 days and ranges from 0 to 42. The daily urticarial activity score is the average of the morning and evening urticarial activity scores and ranges from 0 to 6. The urticarial activity score is the sum of ratings on a scale of 0 to 3 (0=none to 3=intense/severe) for (1) the number of wheals (hives) and (2) itch intensity over the previous 12 hours, ranges from 0 to 6, and is measured twice daily (morning and evening). The Baseline score is the sum of the daily urticarial activity scores over the 7 days prior to the first treatment. A higher urticarial activity score indicates more urticaria activity.