A Study of the Efficacy and Safety of Omalizumab Through 48 Weeks in Participants With Chronic Idiopathic Urticaria
Condition: Urticaria
MeSH terms: Urticaria; Chronic Urticaria
Intervention: Omalizumab; Placebo
Intervention description: Omalizumab 300 mg administered SC Q4W.; Placebo matched to omalizumab administered SC Q4W.
Intervention MeSH terms: Omalizumab
Phase: Phase 4
Study type: Interventional
Primary purpose: Treatment
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Double (Participant, Investigator)
Enrollment: 206.0
Sex: All
Minimum age: 12 Years
Maximum age: 75 Years
Healthy volunteers: No

Summary:

      This multicenter, randomized, double-blind, placebo-controlled study will evaluate the
      efficacy and safety of subcutaneous (SC) omalizumab (Xolair) as an add-on therapy through 48
      weeks for treatment of H1 antihistamine refractory chronic idiopathic urticaria (CIU). After
      completing an initial 24-week open-label treatment period with omalizumab 300 milligrams (mg)
      every 4 weeks (Q4W), participants responding to omalizumab will be randomized at a 3:2 ratio
      (omalizumab:placebo) to either continue omalizumab or be transitioned to placebo for a
      further 24 weeks.
    

Eligibility criteria:

        Inclusion Criteria:

          -  Diagnosis of CIU refractory to H1 antihistamines at baseline

          -  Presence of itch and hives for at least 8 consecutive weeks at any time prior to
             enrollment despite current use of H1 antihistamine treatment (up to four times the
             approved dose) during this time period

          -  UAS7 score (range 0-42) ≥ 16 and itch component of UAS7 (range 0-21) ≥ 8 during 7 days
             prior to baseline

          -  Participants must have been on a non-sedating H1 antihistamine treatment (up to four
             times the approved dose) for CIU for at least 3 consecutive days immediately prior to
             screening visit with continued current use on the day of the initial screening visit

          -  CIU diagnosis for ≥ 6 months

          -  Willing and able to complete a daily symptom eDiary for the duration of the study

        Exclusion Criteria:

          -  Treatment with an investigational agent within 30 days of the initial screening visit

          -  Body weight less than 20 kilograms

          -  Clearly defined underlying etiology for chronic urticarias other than CIU

          -  Evidence of a parasitic infection

          -  Atopic dermatitis, bullous pemphigoid, dermatitis herpetiformis, senile pruritus or
             other skin disease associated with itch

          -  Previous treatment with omalizumab within 1 year prior to the initial screening visit

          -  Participants may not have taken during treatment period or have been taking within 30
             days before the initial screening visit any of the following medications or
             treatments:

        regular (daily/every other day during 5 or more consecutive days) systemic corticosteroids,
        hydroxychloroquine, methotrexate, mycophenolate, cyclosporine, cyclophosphamide,
        intravenous immunoglobulin G or plasmapheresis

          -  Regular (daily/every other day) oral doxepin use within 14 days prior to the initial
             screening visit

          -  Pregnant or lactating women, or women intending to become pregnant during the study