Anaphylaxis to Etanercept in Two Children With Juvenile Idiopathic Arthritis:

Hypersensitivity to Biological Treatments in Juvenile Idiopathic Arthritis: How Should It Be Managed?

Juvenile idiopathic arthritis (JIA) is one of the most frequent diseases in the practice of pediatric rheumatology. JIA treatments have been modified and improved with the use of biological drugs along with technological innovations. However, different types of hypersensitivity reactions to biological drugs have also been reported. Anaphylaxis and infusion reactions occurring during the intravenous infusion require a critical approach in the acute period. On the other hand, the detection of drug-related late-type reactions and the development of antibodies to the agent highlight the need for an understanding of the drug-induced etiology to prevent the patient from continuing the treatment with the culprit drug. The chronic disease process, concomitant immune dysregulation, and multiple drug use may result in these hypersensitivity reactions. In this review, the hypersensitivity reactions to the biological treatments used in patients with juvenile idiopathic arthritis and the management of these conditions are discussed.

Biologics and anaphylaxis

PURPOSE OF REVIEW

The use of biologicals as therapeutic agents in oncology and other inflammatory diseases has dramatically increased during the last years. Due to their biological nature and inherent immunological activity, they are able to induce important adverse events, such as cytokine release reactions (rapid release of proinflammatory cytokines), serum sickness disease, and immediate or delayed hypersensitivity reactions, including anaphylaxis. The aim of the current article is to review the state of the art of anaphylaxis because of biological agents.

RECENT FINDINGS

Different phenotypes, and potential underlying endotypes, have been described in anaphylactic reactions to biologicals. There seems to be a spectrum from type 1 reactions (IgE or non-IgE-mediated) to cytokine release reactions, with some reactions falling in between both. Management should be directed according to such phenotypes.

SUMMARY

There is ongoing research to further define immediate adverse reactions to biologicals and to find relevant biomarkers to aid in their diagnosis. Such information will serve in defining their immediate and long term management.

Subcutaneous Injectable Drugs Hypersensitivity and Desensitization: Insulin and Monoclonal Antibodies

Injectable drugs, including monoclonal antibodies, are becoming crucial components in the management of chronic diseases. The most common side effects are local reactions at the site of administration. With the increased and prolonged use of these medications, we are seeing increased reports of hypersensitivity reactions. The aim of this article is to discuss the signs and symptoms of these reactions as well as management, which may involve desensitization for 3 commonly encountered injectable drugs: tumor necrosis factor-α inhibitors (etanercept and adalimumab), insulin, and omalizumab.

Treatment of juvenile idiopathic arthritis: a revolution in care

A generation ago, children with arthritis faced a lifetime of pain and disability. Today, there are a multitude of treatment options, including a variety of biologics targeting key cytokines and other inflammatory mediators. While non-steroidal anti-inflammatory drugs and corticosteroids were once the mainstay of therapy, they are now largely used as bridge or adjunctive therapies. Among the conventional disease-modifying anti-rheumatic drugs, methotrexate remains first-line therapy for most children with juvenile idiopathic arthritis (JIA) due to its long track record of safety and effectiveness in the management of peripheral arthritis. Sulfasalazine and leflunomide may also have a secondary role. The tumor necrosis factor inhibitors (TNFi) have shown tremendous benefit in children with polyarticular JIA and likely in enthesitis-related arthritis and psoriatic JIA as well. There may be additional benefit in combining TNFi with methotrexate. Abatacept and tocilizumab also appear to benefit polyarticular JIA; the role of rituximab remains unclear. For the treatment of systemic JIA, while the TNFi are of less benefit, blockade of interleukin-1 or interleukin-6 is highly effective. Additionally, interleukin-1 blockade appears to be effective treatment of macrophage activation syndrome, one of the most dangerous complications of JIA; specifically, anakinra in combination with cyclosporine and corticosteroids may obviate the need for cytotoxic approaches. In contrast, methotrexate along with the TNFi and abatacept are effective agents for the management of uveitis, another complication of JIA. Overall, the biologics have demonstrated an impressive safety record in children with JIA, although children do need to be monitored for rare but potentially dangerous adverse events, such as tuberculosis and other infections; paradoxical development of additional autoimmune diseases; and possibly an increased risk of malignancy. Finally, there may be a window of opportunity during which children with JIA will demonstrate most optimal responses to aggressive therapy, underscoring the need for rapid diagnosis and initiation of treatment.

Clinical utility of etanercept in the treatment of arthritides in children and adolescents

Juvenile idiopathic arthritis (JIA) is a group of chronic inflammatory diseases affecting approximately 300,000 children and adolescents in the United States of unknown cause. It can affect children from the age of 0 years up to the age of 16 years. The International League of Associations of Rheumatology has defined seven subsets of JIA based on several factors including the number of affected joints and the involvement of other tissues; the prognosis for each affected child also depends on multiple factors including age of onset, number of joints involved, and systemic features. As with rheumatoid arthritis in adults, the goal of therapy is remission and resolution of disease activity; however, as a cure does not seem attainable in the near future, a reasonable goal of therapy is prevention of joint damage, inhibition of inflammation, and a high level of quality of life. Even with available therapies, many children with JIA enter adulthood with persistently active disease, suboptimal function, and impaired quality of life. Methotrexate remains the standard of care for children with JIA; etanercept was approved in 2000 in the United States for the treatment of JIA resistant to methotrexate. The efficacy and safety of etanercept therapy in children with JIA is reviewed and its place in the therapeutic regimen is discussed; the available long term data is also presented. The data presented was obtained from a PubMed search as well as a review of the references presented in the 2011 American College of Rheumatology Recommendations for the Treatment of Juvenile Idiopathic Arthritis and the 2013 Update. It is hoped that treatment with etanercept and other biologic therapies will lead to improved outcomes for children with JIA in the future.