Treatment to Target Using Recombinant Interleukin-1 Receptor Antagonist as First-Line Monotherapy in New-Onset Systemic Juvenile Idiopathic Arthritis: Results From a Five-Year Follow-Up Study

Interleukin-1 Blockade in Systemic Juvenile Idiopathic Arthritis

Systemic juvenile idiopathic arthritis (sJIA) is a severe disorder now linked more to autoinflammation than to autoimmunity. Clinical and laboratory evidence support the pathogenetic role of interleukin-1 (IL-1), and blockade of this cytokine has proved to be very effective in the treatment of sJIA. There are now several agents that block IL-1 available on the market. This article reviews the efficacy and safety of these drugs for the treatment of sJIA on the basis of published data, and offers the current view on treating sJIA according to its different phenotypes. There are no head to head trials among the different IL-1 inhibitors, and although efficacy has been demonstrated for all of them, it is still unknown which one would be more appropriate for which particular situation. The presence of synovitis in addition to active systemic features might be relevant for these choices. In addition, complications such as macrophage activation syndrome can be important since, on one hand, it has been associated with biologic therapy administration and, on another, there have been some reports of this complication being treated with anti-IL-1. Current recommendations by the American College of Rheumatology are now outdated, and new ones are being prepared. In the meantime, basic and clinical research is advancing in order to identify new treatment targets and to evaluate the different protocols currently in use.

Predicting disease severity and remission in juvenile idiopathic arthritis: are we getting closer?

PURPOSE OF REVIEW

To summarize current research on the prediction of severe disease or remission in children with juvenile arthritis, and define further steps needed towards developing prediction tools with sufficient accuracy for clinical use.

RECENT FINDINGS

High disease activity, poor patient-reported outcomes, ankle or wrist involvement, and a longer time from onset to the start of treatment herald a severe disease course and a low chance of remission. Other studies confirmed that age less than 7 years and positive ANA are the strongest predictors of uveitis development. Preliminary evidence suggests ultrasound findings may predict flare in patients with clinically inactive disease, and several new biomarkers show promise. A few prediction tools that combine predictors to estimate the chance of remission or a severe disease course in the medium-term to long-term have shown good accuracy when internally validated in the population in which they were developed.

SUMMARY

Promising candidate tools for predicting disease severity and long-term remission in juvenile arthritis are now available. These tools need external validation in other populations, and ideally formal trials to assess whether their use in practice improves patient outcomes. We are definitively getting closer, but we are not there yet.

Anakinra in children and adults with Still's disease

Systemic juvenile idiopathic arthritis and adult-onset Still’s disease are rare autoinflammatory disorders with common features, supporting the recognition of these being one disease—Still’s disease—with different ages of onset. Anakinra was recently approved by the European Medicines Agency for Still’s disease. In this review we discuss the reasoning for considering Still’s disease as one disease and present anakinra efficacy and safety based on the available literature. The analysis of 27 studies showed that response to anakinra in Still’s disease was remarkable, with clinically inactive disease or the equivalent reported for 23–100% of patients. Glucocorticoid reduction and/or stoppage was reported universally across the studies. In studies on paediatric patients where anakinra was used early or as first-line treatment, clinically inactive disease and successful anakinra tapering/stopping occurred in >50% of patients. Overall, current data support targeted therapy with anakinra in Still’s disease since it improves clinical outcome, especially if initiated early in the disease course.

Th17 reprogramming of T cells in systemic juvenile idiopathic arthritis

Systemic juvenile idiopathic arthritis (sJIA) begins with fever, rash, and high-grade systemic inflammation but commonly progresses to a persistent afebrile arthritis. The basis for this transition is unknown. To evaluate a role for lymphocyte polarization, we characterized T cells from patients with acute and chronic sJIA using flow cytometry, mass cytometry, and RNA sequencing. Acute and chronic sJIA each featured an expanded population of activated Tregs uncommon in healthy controls or in children with nonsystemic JIA. In acute sJIA, Tregs expressed IL-17A and a gene expression signature reflecting Th17 polarization. In chronic sJIA, the Th17 transcriptional signature was identified in T effector cells (Teffs), although expression of IL-17A at the protein level remained rare. Th17 polarization was abrogated in patients responding to IL-1 blockade. These findings identify evolving Th17 polarization in sJIA that begins in Tregs and progresses to Teffs, likely reflecting the impact of the cytokine milieu and consistent with a biphasic model of disease pathogenesis. The results support T cells as a potential treatment target in sJIA.

Current and emerging biologics for the treatment of juvenile idiopathic arthritis

INTRODUCTION

The management of a child with juvenile idiopathic arthritis (JIA) requires a combination of pharmacological, physical, and psychosocial therapies in order to induce disease remission, by controlling articular and systemic inflammation. This review aims to provide a comprehensive discussion on the biological therapies currently in use in the treatment of JIA referring to existing recommendations and clinical evidence. We also discuss on the emerging biological drugs actually under consideration.

AREAS COVERED

Recent findings on immunological mechanisms involved in the pathogenesis of the disease allowed us to identify several specific targets for biologic therapies. A systematic literature review was conducted between January 1997 and January 2020 on PubMed including national and international guidelines and recommendations, trials and case-control studies.

EXPERT OPINION

There is now a plethora of therapies that are directed against variable targets, and the physician has to choose the most appropriate available medication in order to achieve early and sustained remission with as few side effects as possible. Research is advancing very fast in order to be more and more specific in suppressing inflammatory pathways without harming natural defenses. Finally, pharmacoeconomic considerations will also be very important to deal with, considering the high cost of most of these molecules.

Comparison of Early vs. Delayed Anakinra Treatment in Patients With Adult Onset Still's Disease and Effect on Clinical and Laboratory Outcomes

Background: Aim of this study was to search for any difference in the outcome of patients with adult onset Still's disease (AOSD) treated with anakinra (ANK) in relation with the interval between disease onset and the start of anti-interleukin(IL)-1 treatment and according with the different lines of ANK treatment.

Patients and Methods: One hundred and forty-one AOSD patients treated with ANK have been retrospectively assessed. Statistically significant differences (p < 0.05) were analyzed in the frequency of ANK effectiveness, primary or secondary inefficacy to ANK and rate of resolution of clinical and laboratory AOSD manifestations after 3, 6, and 12 months since ANK treatment according with different lines of treatment and different times between AOSD onset and start of ANK.

Results: No significant differences were identified in the ANK effectiveness and frequency of primary or secondary inefficacy for patients starting ANK within 6 months (p = 0.19, p = 0.14, and p = 0.81, respectively) or 12 months (p = 0.37, p = 0.23, and p = 0.81, respectively) since AOSD onset compared with patients starting ANK thereafter; no significant differences were identified in ANK effectiveness and primary or secondary inefficacy according with different lines of ANK treatment (p = 0.06, p = 0.19, and p = 0.13, respectively). Patients starting ANK within 6 and 12 months since AOSD onset showed a significantly quicker decrease of erythrocyte sedimentation rate and C-reactive protein than observed among patients undergoing ANK treatment after 6 and 12 months. The number of swollen joints at the 3 month follow-up visit was significantly lower among patients undergoing ANK within 6 months since AOSD onset (p = 0.01), while no significance was identified at the 6 and 12 month assessments (p = 0.23 and p = 0.45, respectively). At the 3 and 6 month visits, the number of swollen joints was significantly higher among patients previously treated with conventional and biological disease modifying anti-rheumatic drugs (DMARDs) compared with those formerly treated only with conventional DMARDs (p < 0.017).

Conclusions: Clinical and therapeutic outcomes are substantially independent of how early ANK treatment is started in AOSD patients. However, a faster ANK effectiveness in controlling systemic inflammation and resolving articular manifestations may be observed in patients benefiting from IL-1 inhibition as soon as after disease onset.

Macrophage Activation Syndrome and Secondary Hemophagocytic Lymphohistiocytosis in Childhood Inflammatory Disorders: Diagnosis and Management

Macrophage activation syndrome (MAS), a form of secondary hemophagocytic lymphohistiocytosis, is a frequently fatal complication of a variety of pediatric inflammatory disorders. MAS has been most commonly associated with systemic juvenile idiopathic arthritis (sJIA), as approximately 10% of children with sJIA develop fulminant MAS, with another 30-40% exhibiting a more subclinical form of the disease. Children with other rheumatologic conditions such as systemic lupus erythematosus and Kawasaki disease are also at risk for MAS. Moreover, MAS also complicates various genetic autoinflammatory disorders such as gain of function mutations in the cytosolic inflammasome NLRC4, pediatric hematologic malignancies (e.g., T-cell lymphoma), and primary immunodeficiencies characterized by immune dysregulation. Disease-specific and broadly inclusive diagnostic criteria have been developed to facilitate the diagnosis of MAS. Recently, simple screening tools such as the serum ferritin to erythrocyte sedimentation rate ratio have been proposed. Early diagnosis and rapid initiation of immunosuppression are essential for the effective management of MAS. With a better understanding of the pathophysiology of MAS and the advent of novel therapeutics, a broad immunosuppressive approach to treatment is giving way to targeted anti-cytokine therapies. These treatments include agents that block interleukin-1 (IL-1), IL-6, IL-18, interferon-γ, as well as inhibitors of downstream targets of cytokine signaling (e.g., Janus kinases). Increased early recognition of MAS among pediatric inflammatory disorders combined with the use of effective and less toxic cytokine-targeted therapies should lower the mortality of this frequently fatal disorder.

Innately Adaptive or Truly Autoimmune: Is There Something Unique About Systemic Juvenile Idiopathic Arthritis?

Systemic juvenile idiopathic arthritis (JIA) is a form of arthritis in childhood that is initially dominated by innate immunity-driven systemic inflammation and is thus considered a polygenic autoinflammatory disease. However, systemic JIA can progress toward an adaptive immunity-driven afebrile arthritis. Based on this observation of biphasic disease progression, a "window of opportunity" for optimal, individualized and target-directed treatment has been proposed. This hypothesis requires testing, and in this review we summarize current evidence regarding molecular factors that may contribute to the progression from an initially predominantly autoinflammatory disease phenotype to autoimmune arthritis. We consider the involvement of innately adaptive γδ T cells and natural killer T cells that express γδ or αβ T cell receptors but cannot be classified as either purely innate or adaptive cells, versus classic B and T lymphocytes in this continuum. Finally, we discuss our understanding of how and why some primarily autoinflammatory conditions can progress toward autoimmune-mediated disorders over the disease course while others do not and how this knowledge may be used to offer individualized treatment.

Case Report: Case Series of Children With Multisystem Inflammatory Syndrome Following SARS-CoV-2 Infection in Switzerland

Since the beginning of the severe SARS-CoV-2 pandemic, an increasing number of countries reported cases of a systemic hyperinflammatory condition defined as multi-system inflammatory syndrome in children (MIS-C). The clinical features of MIS-C can be an overlap of Kawasaki Disease (KD), Toxic Shock Syndrome (TSS), Macrophage Activation Syndrome (MAS), or have often an acute abdominal presentation. Intravenous immunoglobulin (IVIG) is recommended as first line therapy in KD. Recent evidence suggests intravenous immunoglobulins (IVIG) resistance in some cases of SARS-CoV-2 related MIS-C, thereby questioning the benefit of immunomodulators such as IL-1 or IL-6 blocking agents. We report on a cohort of 6 Swiss children with SARS-CoV2 related MIS-C presenting with clinical features compatible with Incomplete KD and Toxic Shock Syndrome associated to a cytokine storm. Serum cytokine profile investigations showed increased IL1RA levels (8 to 22-fold) in 5 of the 6 patients (one patient had not been tested), whereas, IL-6 serum levels were increased only in the 3 patients of the 6 who were tested. With exception of one patient who had only benefited by Anakinra, all patients received at least one dose of IVIG. One patient has only received Anakinra with favorable evolution, and three patients had also a steroid treatment. In addition to all this anti-inflammatory medication two patients have also received one dose of anti-IL6. In conclusion, our case series reports on clinical and laboratory findings of most of Swiss cases with MIS-C and suggests the use of Anakinra as an alternative to steroids in these children, most of whom presented with high IL-1RA levels.

Emergent high fatality lung disease in systemic juvenile arthritis

OBJECTIVE

To investigate the characteristics and risk factors of a novel parenchymal lung disease (LD), increasingly detected in systemic juvenile idiopathic arthritis (sJIA).

METHODS

In a multicentre retrospective study, 61 cases were investigated using physician-reported clinical information and centralised analyses of radiological, pathological and genetic data.

RESULTS

LD was associated with distinctive features, including acute erythematous clubbing and a high frequency of anaphylactic reactions to the interleukin (IL)-6 inhibitor, tocilizumab. Serum ferritin elevation and/or significant lymphopaenia preceded LD detection. The most prevalent chest CT pattern was septal thickening, involving the periphery of multiple lobes ± ground-glass opacities. The predominant pathology (23 of 36) was pulmonary alveolar proteinosis and/or endogenous lipoid pneumonia (PAP/ELP), with atypical features including regional involvement and concomitant vascular changes. Apparent severe delayed drug hypersensitivity occurred in some cases. The 5-year survival was 42%. Whole exome sequencing (20 of 61) did not identify a novel monogenic defect or likely causal PAP-related or macrophage activation syndrome (MAS)-related mutations. Trisomy 21 and young sJIA onset increased LD risk. Exposure to IL-1 and IL-6 inhibitors (46 of 61) was associated with multiple LD features. By several indicators, severity of sJIA was comparable in drug-exposed subjects and published sJIA cohorts. MAS at sJIA onset was increased in the drug-exposed, but was not associated with LD features.

CONCLUSIONS

A rare, life-threatening lung disease in sJIA is defined by a constellation of unusual clinical characteristics. The pathology, a PAP/ELP variant, suggests macrophage dysfunction. Inhibitor exposure may promote LD, independent of sJIA severity, in a small subset of treated patients. Treatment/prevention strategies are needed.

Treatment Withdrawal Following Remission in Juvenile Idiopathic Arthritis: A Systematic Review of the Literature

BACKGROUND

Early diagnosis and treatment of juvenile idiopathic arthritis (JIA) with conventional and biologic disease-modifying anti-rheumatic drugs have vastly improved outcomes for children with these diseases. Currently, a large proportion of children with JIA are able to achieve clinical inactive disease and remission. With this success, important questions have arisen about when medications can be stopped and how to balance the risks and benefits of continuing medications versus the potential for flare after stopping.

AIM

The aim was to conduct a systematic review of the available literature to summarize current evidence about medication withdrawal for JIA in remission.

METHODS

We conducted a systematic literature search in PubMed and Embase from 1990 to 2019. References were first screened by title and then independently screened by title and abstract by two authors. A total of 77 original papers were selected for full-text review. Data were extracted from 30 papers on JIA and JIA-associated uveitis, and the quality of the evidence was evaluated using National Institutes of Health (NIH)/National Heart, Lung, and Blood Institute (NHLBI) tools. Studies on biochemical and radiologic biomarkers were also reviewed and summarized.

RESULTS

Most studies investigating treatment withdrawal in JIA have been observational and of poor or fair quality; interpretations of these studies have been limited by differences in study populations, disease and remission durations, the medications withdrawn, approaches to withdrawal, and definitions of disease outcomes. Overall the data suggest that flares are common after stopping JIA medications, particularly biologic medications. Clinical characteristics associated with increased risks of flare have not been consistently identified. Biochemical biomarkers and ultrasound findings have been shown to predict outcomes after stopping medications, but to date, no such predictor has been consistently validated across JIA populations. Studies have also not identified optimal strategies for withdrawing medication for well-controlled JIA. Promising withdrawal strategies include discontinuing methotrexate before biologic medications in children receiving combination therapy, dose reduction for children on biologics, and treat-to-target approaches to withdrawal. These and other strategies require further investigation in larger, high-quality studies.

CONCLUSIONS

The published literature on treatment withdrawal in JIA has varied in design and quality, yielding little conclusive evidence thus far on the management of JIA in remission. Given the importance of this question, international collaborative efforts are underway to study clinical and biologic predictors of successful medication withdrawal in JIA. These efforts may ultimately support the development of personalized approaches to withdrawing medication in children with JIA in remission.