Impact of Omalizumab on Quality of Life Measures and Angioedema Occurrence in Patients With CSU Refractory to Therapy (X-ACT)

• Chronic urticaria quality of life questionnaire (CU-Q2oL) [ Time Frame: Baseline/week 28 ] [ Designated as safety issue: No ]
  The CU-Q2oL is a questionnaire that measures the relative burden of chronic urticaria on subjective well-being. It consists of 23 questions in 3 domains (symptoms, general impairment, difficulties and problems due to urticaria). Patients are asked to respond how much they are troubled by each problem on a 5-point Likert scale (1= not at all to 5= very much). An overall score is calculated and normalized to a scale of 1 to 100.
  
  

• Angioedema Quality of Life Score (AE-Q2oL) [ Time Frame: Baseline/week 28 ] [ Designated as safety issue: No ]
  The AE-Q2oL is a questionnaire for patients suffering from angioedema. It consists of 29 questions relevant to angioedema and its specific impact on quality of life. Patients are asked to respond how much they are troubled be each problem on a 5-point Likert scale (1= does not apply to 5= very much). An overall score is calculated and a higher score indicates lower quality of life. A negative change score (week 28 score minus baseline score) indicates improvement.
  
  
• Weekly Urticaria Score (UAS7) [ Time Frame: Baseline/week 28 ] [ Designated as safety issue: No ]
  A cumulative activity score, evaluated in the screening period and throughout the study. The records each evening on a daily basis symptoms of itch and hives into a patient diary. The UAS is a composite score with numeric severity intensity ratings on a scale of 0 - 3 for the number of wheals (hives) and the itch intensity. The UAS7 is the sum of the daily UAS scores over 7 days.
  
  
• Use of rescue medication [ Time Frame: Baseline/week 28 ] [ Designated as safety issue: No ]
  The intake of sedating anti-histamines as well as the use of corticosteroids will be measured on a daily basis throughout the study and summarized descriptively. The amount and rate of required rescue medication will be summarized and compared inferentially between treatment groups.
  
  

This study will be conducted using a double-blind, placebo-controlled, randomized, multicenter design to investigate the impact of omalizumab on Quality of Life (QoL) in Chronic Spontaneous Urticaria (CSU) and will assess its effectiveness in reducing and/or inhibiting the occurrence, time-course and severity of angioedema episodes.

Omalizumab is administered subcutaneously every 4 weeks as an add-on therapy to the current approved treatment of adult CSU patients. The treatment period is 28 weeks which is followed by an 8-week follow-up. The study aims to enroll approximately 70 patients.

The study is divided into a 2-week screening period, a 28-week double-blind treatment phase with omalizumab or placebo-omalizumab, and an 8-week follow-up phase.