Efficacy Study of Canakinumab to Treat Urticaria

Inclusion criteria * Diagnosis of chronic idiopathic urticaria for more than 6 weeks as confirmed by clinical and, if necessary, histological examination * CIU of moderate to severe severity defined by all of the following * Physician severity score of 2 or 3 (on a scale from 0 - 3) * Run-in period of the diary-based UAS7 score of \> 21 (on a scale from 0 - 42) * Symptomatic despite use of non-sedating antihistamine with or without concomitant leukotriene antagonist/corticosteroids * Use of maintenance non-sedating antihistamine at a stable dose for at least 1 week prior to entering run-in period * Maintenance corticosteroids at a dose of \<20 mg/day or \<0.4 mg/kg stable for at least the week prior to study entry for treatment of the patient's CIU will be allowed. * Age: \> 18 years. * Signed informed consent * Negative or unreactive QuantiFERON test (QFT-TB G In-Tube) or history of adequate treatment of active or latent tuberculosis. Exclusion criteria: * Age \< 18 or \> 70 years * History of cancer except for treated basal cell carcinoma of the skin * With active or recurrent bacterial, fungal or viral infection at the time of enrollment, including patients with evidence of Human Immunodeficiency Virus (HIV) infection, Hepatitis B and Hepatitis C infection, active or untreated latent tuberculosis. * Patients currently treated with systemic immunosuppressive agents or following treatments in the specified period before the baseline visit: * corticosteroids =20 mg/day or \>0.4 mg/kg for 1 week prior to study entry; * leukotriene antagonists for 1 week prior to study entry * colchicine, dapsone or mycophenolate mofetil for 3 weeks; * etanercept, leflunomide (documentation of a completion of a full cholestyramine elimination treatment after most recent leflunomide use will be required), thalidomide or ciclosporin for 4 weeks; * adalimumab or intravenous immunoglobulin for 8 weeks; * infliximab, 6-mercaptopurine, azathioprine, cyclophosphamide or chlorambucil for 12 weeks * Live vaccinations within 3 months prior to the start of the trial, during the trial, and up to 3 months following the last dose * Contraindications to the class of drugs under study, e.g. known hypersensitivity or allergy to class of drugs or the investigational product, * Pregnant or lactating women, patients (men or women) planning a pregnancy during the duration of the study, lack of safe contraception. * Safe contraception is defined as follows: * Double-barrier contraception such as oral, injectable, or implantable contraceptives, or intrauterine contraceptive devices together with condom use. * Both men and women must use safe contraception (double-barrier as defined above) during the duration of the study and until 6 months after the study. * Please note that female subjects who are surgically sterilized/hysterectomized or post-menopausal for longer than 2 years are not considered as being of child bearing potential. * Inability to follow the procedures of the study, e.g. due to language problems, psychological disorders, dementia, etc. of the subject. * Participation in another study with investigational drug within the 30 days preceding and during the present study. * Previous enrolment into the current study. * Enrolment of the investigator, his/her family members, employees and other dependent persons.