Real Life Use of Omalizumab in Chronic Urticaria

Study Overview
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Brief Summary
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Chronic urticaria affects up to 1% of the population. Chronic urticaria refractory to updosing antihistamines can benefit from OMALIZUMAB, which is an anti-IgE IgG1 monoclonal antibody administrated every 4 weeks subcutaneously which represents a cost of nearly 800€/month excluding nurse fees. Efficacy and good tolerance have already been demonstrated in real-life large cohorts of patients. A 6 months treatment duration is proposed before evaluating the efficacy and discontinuating the treatment in the absence of adequate response. Mean duration of chronic urticaria is 3 to 5 years with high standard deviations. Therefore, optimal duration of treatment with OMALIZUMAB is unknown and discontinuation modalities differ between physicians. The aim of this study is to evaluate the mean duration between initiation and first discontinuation of OMALIZUMAB in patients treated for chronic urticaria and explore the different factors influencing this duration and its outcome.

Detailed Description
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Chronic urticaria affects up to 1% of the population. Rarely, chronic urticaria may be refractory to updosing four-fold antihistamine drugs and then can be improved with subcutaneous OMALIZUMAB. OMALIZUMAB is available for chronic urticaria since 2015. It is an IgG1 monoclonal antibody targeting IgE and administrated every 4 weeks which represent a cost of nearly 800€/month excluding nurse fees. Efficacy and good tolerance have already been demonstrated in real-life large cohorts of patients. A 6 months treatment duration is proposed before evaluating the efficacy and discontinuating the treatment in the absence of adequate response. Mean duration of chronic urticaria is 3 to 5 yearss with high standard deviations. Therefore, optimal duration of treatment with OMALIZUMAB is unknown and discontinuation modalities differ between physicians. The aim of this study is to evaluate the mean duration between initiation and first discontinuation of OMALIZUMAB in patients treated for chronic urticaria and explore the different factors influencing this duration and its outcome. To accomplish this, the investigators will conduct a restrospective analyse of all patients treated with OMALIZUMAB for chronic urticaria from 2010 to 2020 in the major French hospital reference centers for chronic urticaria management : Paris, Lyon, Grenoble, Lille, Bordeaux, Nantes, Rouen, Saint-Etienne, Montpellier.

Official Title
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Drug Survival of Omalizumab in Chronic Urticaria : a Retrospective Multicentric Study

Conditions
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Chronic Urticaria

Participation Criteria
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Eligibility Criteria
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Inclusion criteria: chronic spontaneous or inducible urticaria treated with omalizumab at least once between January the 1st 2010 and july 2020. Exclusion criteria: unknown intiation and discontinuation date of omalizumab omalizumab initiated for asthma other diagnosis (vascularitis, aquagenic pruritus)
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| duration between initiation and first discontinuation of OMALIZUMAB | assessed at the time of inclusion Description: duration between initiation and first discontinuation of OMALIZUMAB | 1 day | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| predictive factors of duration between initiation and first discontinuation of omalizumab | predictive factors of duration between initiation and first discontinuation of omalizumab | 1 day | 
| efficacy of omalizumab and relapse at discontinuation | efficacy of omalizumab and relapse at discontinuation | 1 day | 
| discontinuation cause | discontinuation cause | 1 day | 
| rechallenge with omalizumab and efficacy | rechallenge with omalizumab and efficacy | 1 day | 
| persistance of antihistamine intake at 1year, 2 years and 3 years | persistance of antihistamine intake at 1year, 2 years and 3 years | at 1year, 2years and 3years | 
| mid and long-term tolerance of omalizumab. | mid and long-term tolerance of omalizumab. | 1 day | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Chronic urticaria treated with OMALIZUMAB