Study of Antibodies to Anti-TNF Agents in Juvenile Idiopathic Arthritis

Study Overview
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Brief Summary
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The purpose of this study is to analyze the frequency of the formation of antibodies against three different anti-TNF biologic agents used for the therapy of juvenile idiopathic arthritis.

Detailed Description
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Juvenile idiopathic arthritis (JIA) is the umbrella term for a heterogeneous group of inflammatory arthropathies that can affect children and young adults and is the most common rheumatic disease of the pediatric population. In high-income countries it has a yearly incidence of 2-20 cases per 100 000 population and a prevalence of 16-150 cases per 100 000 population. Treatment of JIA includes a combination of pharmacological interventions, physical and occupational therapy, and psychosocial support. Although a definitive cure is still not available, the prognosis for patients with JIA has improved greatly in recent years due to improved disease management and with the introduction of biologics that can provide an efficient alternative for patients who are nonresponsive to other treatments. Traditionally, biologic treatments in JIA have focused on blocking one of the central mediators of the inflammatory response, the cytokine tumor necrosis factor (TNF). Currently there are three anti-TNF agents available for the treatment of JIA: infliximab, adalimumab and etanercept. One of the major drawbacks of these therapeutics is the production of anti-drug antibodies (ADA) that have been correlated with an increased risk of adverse events and loss of drug efficacy. The study will evaluate the frequency of the formation of anti-infliximab antibodies in patients treated with infliximab, anti-adalimumab antibodies in patients treated with adalimumab and anti-etanercept antibodies in patients treated with etanercept. A common practice in cases nonresponsive to one of the described anti-TNF agents is the discontinuation of therapy and switching to a different ant-TNF agent. Therefore, the frequency of the formation of antibodies to each of the described anti-TNF agents will also be compared between patients who have previously received a different anti-TNF agent and patients who have not received any previous anti-TNF therapy. The results of this study will highlight the risks of formation of antibodies to three different anti-TNF biologic agents used for the therapy of JIA either alone or after the previous discontinuation of a different anti-TNF agent.

Official Title
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Analysis of Anti-infliximab, Anti-adalimumab and Anti-etanercept Antibodies in Children and Young Adolescents With Juvenile Idiopathic Arthritis

Conditions
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Juvenile Idiopathic Arthritis

Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Clinical diagnosis of juvenile idiopathic arthritis Must be treated either with infliximab, adalimumab or etanercept Exclusion Criteria: Contraindications to anti-TNF therapy Concurrent treatment with any biologic agent other than infliximab, etanercept, or adalimumab Previous treatment with rituximab

Ages Eligible for Study
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Minimum Age: 1 Year
Maximum Age: 16 Years

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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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| anti-TNF treatment<br>Children or young adolescents with juvenile idiopathic arthritis receiving either infliximab, adalimumab or etanercept. | |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determination of the presence and quantification of anti-drug antibodies by ELISA or other immunoassay. | In patients receiving infliximab anti-infliximab antibodies will be measured, in patients receiving adalimumab anti-adalimumab antibodies will be measured and in patients receving etanercept anti-etanercept antibodies will be measured. In all cases the primary outcome measure will be the determination of the presence of these antibodies (YES/NO) and their quantification (in EqU compared to a reference serum) using ELISA or other suitable immunoassay. | Up to one year | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Determination of the presence and quantification of the serum level of the anti-TNF agent used for JIA therapy by ELISA or other immunoassay. | In patients receiving infliximab the trough serum level of infliximab will be measured, in patients receiving adalimumab the trough serum level of adalimumab will be measured and in patients receiving etanercept the trough serum level of etanercept will be measured by ELISA or other suitable immunoassay. | Up to one year | 
| Determination of the presence and quantification of the isotypes and subtypes of the anti-drug antibodies by ELISA or other immunoassay. | In samples where the presence of anti-infliximab, anti-adalimumab or anti-etanercept antibodies will be confirmed, the isotypes and/or subtypes of the antibodies will be determined by ELISA or other suitable immunoassay. | Up to one year. | 
| Time to first detection of anti-drug antibodies. | The elapsed time from start of therapy until first detection of anti-drug antibodies will assessed. | Up to one year. | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Juvenile idiopathic arthritis, Rheumatic diseases, Antibodies, Biological therapy