Comparisons of the outcomes between early and late tocilizumab treatment in systemic juvenile idiopathic arthritis

The inequity of global healthcare in pediatric rheumatology

In pediatric rheumatology, global health inequity relates to the uneven distribution of healthcare resources, accessibility, and health outcomes among children with rheumatic conditions across various countries, regions, and socioeconomic groups. This inequity can manifest in various ways. This review article provides an overview of common rheumatic diseases, such as juvenile idiopathic arthritis and systemic lupus erythematosus, which significantly contribute to and are affected by disparities in global healthcare. Subsequently, we delve into the inequalities in accessing patient care, encompassing issues related to diagnosis and treatment. Additionally, we address challenges in educational advancement and identify research gaps within the field of pediatric rheumatology. We also reveal successful global collaborations, such as a Global Task Force for Pediatric Musculoskeletal Health and special working groups among international organizations, aimed at bridging the disparities gap. Through these efforts, we try to enhance understanding, cooperation, and resource allocation to ensure equal access to quality care worldwide for children with rheumatic conditions. Futhermore, we present a case study from Thailand, highlighting their successful initiatives in developing pediatric rheumatology within their healthcare system.

Recent advances and evolving concepts in Still's disease

Still's disease is a rare inflammatory syndrome that encompasses systemic juvenile idiopathic arthritis and adult-onset Still's disease, both of which can exhibit life-threatening complications, including macrophage activation syndrome (MAS), a secondary form of haemophagocytic lymphohistiocytosis. Genetic insights into Still's disease involve both HLA and non-HLA susceptibility genes, suggesting the involvement of adaptive immune cell-mediated immunity. At the same time, phenotypic evidence indicates the involvement of autoinflammatory processes. Evidence also implicates the type I interferon signature, mechanistic target of rapamycin complex 1 signalling and ferritin in the pathogenesis of Still's disease and MAS. Pathological entities associated with Still's disease include lung disease that could be associated with biologic DMARDs and with the occurrence of MAS. Historically, monophasic, recurrent and persistent Still's disease courses were recognized. Newer proposals of alternative Still's disease clusters could enable better dissection of clinical heterogeneity on the basis of immune cell profiles that could represent diverse endotypes or phases of disease activity. Therapeutically, data on IL-1 and IL-6 antagonism and Janus kinase inhibition suggest the importance of early administration in Still's disease. Furthermore, there is evidence that patients who develop MAS can be treated with IFNγ antagonism. Despite these developments, unmet needs remain that can form the basis for the design of future studies leading to improvement of disease management.

The latest advances in the use of biological DMARDs to treat Still's disease

INTRODUCTION

Currently, the therapeutic management of Still's disease, a multisystemic inflammatory rare disorder, is directed to target the inflammatory symptoms and signs of patients. The treatment varies from glucocorticoids to disease-modifying antirheumatic drugs (DMARDs), both conventional synthetic and biological (bDMARDs). Usually, in refractory patients, bDMARDs are administered.

AREAS COVERED

Among bDMARDs, IL-1 and IL-6 inhibitors are frequently used, as data reported from both clinical trials and 'real-life' experiences. Recently, innovative therapeutic strategies have suggested an early administration of bDMARDs to increase the rate of clinical response and drug-free remission. Some new targets have been also proposed targeting IL-18, IFN-γ, and JAK/STAT pathway, which could be applied to Still's disease and its life-threatening evolution.

EXPERT OPINION

Many lines of evidence improved the knowledge about the therapeutic management of Still's disease with bDMARDs. However, many unmet needs may be still highlighted which could provide the basis to arrange further specific research in increasing the rate of clinical response. In fact, Still's disease remains a highly heterogeneous disease suggesting possible diverse underlying pathogenic mechanisms, at least partially, and consequent different therapeutic strategies. A better patient stratification may help in arranging specific studies to improve the long-term outcome of Still's disease.

Comparison of the outcomes between early and late anti-tumor necrosis factor therapy in patients with enthesitis-related subcategory of juvenile idiopathic arthritis: a multi-center study in Southeast Asia

BACKGROUND

Little is known about the impact of delayed initiation of anti-tumor necrosis factor (TNF) therapy in patients with enthesitis-related arthritis (ERA). Here, we compared the impact of delayed treatment on disease outcomes of ERA patients in Southeast Asia.

RESEARCH DESIGN AND METHODS

This retrospective study enrolled 149 ERA patients from Thailand and Singapore. Early (e-aTNF) and late (l-aTNF) treatment groups received anti-TNF therapy starting at ≤6 months and >6 months, respectively, after diagnosis. Outcomes included mean differences in disease activity parameters, Juvenile Spondyloarthritis Disease Activity (JSpADA) score, Juvenile Arthritis Diseases Activity (JADAS)-10 score, and American College of Rheumatology Pediatric (ACR Pedi) criteria, and the frequency of clinically inactive disease and first flare event.

RESULTS

The mean changes in JSpADA (p = 0.002) and JADAS-10 (p < 0.001) scores over time were significantly higher in the e-aTNF group than in the l-aTNF group. A significantly higher proportion of patients in the e-aTNF group than l-aTNF group satisfied ACR Pedi 100 criteria at 2 years (p = 0.042). All other long-term outcomes were not significantly different between the groups.

CONCLUSIONS

Although early anti-TNF treatment improved disease activity parameters somewhat better than delayed anti-TNF therapy, there was no significant difference in long-term outcomes.

Short-Term Outcomes and Predictors of Effectiveness of Tocilizumab in Systemic Juvenile Idiopathic Arthritis: A Prospective Cohort Study

Background: Systemic Juvenile Idiopathic Arthritis (sJIA) is a unique category of juvenile arthritis in which interleukin 6 plays a major pathogenic role. This study aimed to describe the therapeutic short-term outcomes among patients with sJIA starting tocilizumab (TCZ) therapy and to identify possible predictors of treatment response. Methods: We conducted a prospective observational study including 65 patients with sJIA meeting ILAR classification criteria with active disease despite conventional therapy that were treated by TCZ between August 2019 and October 2020 as the first-line biological therapy. Clinical and serological parameters were recorded at baseline and after 1 year of TCZ therapy. Results: After 1 year, 25% of the patients achieved minimal disease activity and 35% achieved clinically inactive disease. A significant reduction of the 10-joint juvenile arthritis disease activity score and acute phase reactants was also observed. Patients with younger age (≤7 years), shorter disease duration (≤3 years), lower disease activity, and higher serum ferritin and systemic manifestations showed more favorable results. Conclusion: Patients with sJIA showed favorable disease outcomes with TCZ treatment for 1 year, especially if the drugs were administered earlier in the disease course and in younger patients with a more pronounced inflammatory status. Our results may help to define the profile of patients with sJIA who are more likely to benefit from IL-6 blockade.

Tocilizumab in Systemic Juvenile Idiopathic Arthritis: Response Differs by Disease Duration at Medication Initiation and by Phenotype of Disease

Objective: We performed a single-center retrospective study to determine the different efficacy of tocilizumab (TCZ) in the early and late stages and in three phenotypic subgroups (monocyclic, polycyclic, and persistent) of systemic juvenile idiopathic arthritis (sJIA). Methods: Clinical and serological parameters of 77 sJIA patients treated by TCZ were collected from November 1, 2013 to May 1, 2019. Patients were grouped based on the duration group A < 6 months (n = 41) and group B > 6 months (n = 36) and divided into three phenotypes: monocyclic (n = 12), polycyclic (n = 14), and persistent (n = 51) course. Results: At baseline, group A had pronounced ESR, fever less active arthritis than group B (p < 0.05). After 12 weeks of therapy, TCZ alleviated fever, ESR, CRP, and systemic-onset juvenile arthritis disease activity score-27 (sJADAS27) in both group A and group B (p>0.05), while the efficacy of TCZ in relieving active arthritis in group A was better than that in group B (p<0.05). After 1 year of TCZ therapy, it showed that patients with monocyclic phenotype had the highest clinical response rate (91.7%, odds ratio = 0, 95% CI: 24-24, p = 0.00), followed by the polycyclic (28.6%, odds ratio = 2.1, 95% CI: 10.5-18.8, p = 0.00) and the persistent course (9.8%, odds ratio = 1.2, 95% CI: 9.5-13.8, p = 0.00). Conclusion: TCZ can quickly relieve fever and inflammation, especially when patients have less active arthritis with shorter disease duration. The long-term efficacy of TCZ is related to the phenotypes, among which the monocyclic is the best, and the persistent is the worst.

Cost-utility and budget impact analysis of tocilizumab for the treatment of refractory systemic juvenile idiopathic arthritis in Thailand

OBJECTIVES

This study aimed to analyse the cost-utility and budget impact of adding tocilizumab to the standard treatment for patients with refractory systemic juvenile idiopathic arthritis (sJIA) in Thailand.

DESIGN

Economic evaluation using a decision-analytical model.

SETTING

Thailand.

PARTICIPANTS

Patients with refractory sJIA who were ≥2 years old.

METHODS

The use of tocilizumab as an add-on therapy to standard treatment was compared with standard treatment alone. A simulated health state transition model was used to estimate the lifetime costs and health outcomes from a societal perspective. Direct medical costs were collected from tertiary hospital databases while direct non-medical costs were derived from interviews. Health-related quality of life (QoL) was measured using the proxy version of three-level EuroQol five-dimensional questionnaire (EQ-5D-3L). Future costs and outcomes were discounted at an annual rate of 3%. The base case population was patients aged 9.41 years old at refractory disease onset. The results were reported as incremental cost-effectiveness ratios (ICER) in US dollar (USD). One-way and probabilistic sensitivity analysis were conducted to investigate parameter uncertainty. The 5-year budget impact was estimated from a governmental perspective.

RESULTS

The ICER of standard treatment plus tocilizumab was US$35 799 per quality-adjusted life-year (QALY) gained compared with standard treatment alone, which was not cost-effective at the threshold of US$5128 per QALY gained. The estimated 5 years budget impact was approximately US$4.8 million.

CONCLUSIONS

The use of standard treatment plus tocilizumab was not cost-effective in the Thai context, which has limited data. However, there is currently no second-line treatment for refractory sJIA in the Thai National List of Essential Medicines; thus, patients must receive higher doses of standard treatment which can cause many side effects. In contrast, tocilizumab showed obvious efficacy in clinical trials in improving treatment response and QoL. Therefore, the price of tocilizumab should be negotiated to reduce the financial impact on the healthcare system.

Short-term outcomes in patients with systemic juvenile idiopathic arthritis treated with either tocilizumab or anakinra

Objectives

To investigate real-world short-term outcomes among patients with systemic JIA starting tocilizumab or anakinra.

Methods

This analysis included all systemic JIA patients within the UK Biologics for Children with Rheumatic Diseases study starting tocilizumab or anakinra between 2010 and 2016. Disease activity was assessed at baseline and one year. At one year the following outcomes were assessed: minimal disease activity, clinically inactive disease, 90% ACR Paediatric response (ACRPedi90). Univariable logistic regression was used to identify baseline characteristics associated with these outcomes. Multiple imputation was used to account for missing data.

Results

Seventy-six systemic JIA patients were included (54 tocilizumab; 22 anakinra). More patients starting anakinra as their first biologic compared with tocilizumab (86% vs 63%; P = 0.04), with shorter disease duration (1 vs 2 years; P = 0.003) and higher frequency of prior macrophage activation syndrome (37% vs 8%; P = 0.004). Overall, at one year, 42% achieved ACRPedi90, 51% minimal disease activity, and 39% clinically inactive disease, with similar responses seen between the two drugs. Response was not associated with baseline disease characteristics. Fifteen (20%) patients stopped biologic treatment by one year. Treatment survival was better with tocilizumab (89% at one year vs 59% anakinra; P = 0.002), with three stopping for anakinra injection-related problems.

Conclusion

In this real-world cohort of patients with systemic JIA receiving tocilizumab or anakinra, approximately half achieved a minimal disease state by one year. Treatment responses appeared similar between the two therapies albeit with better persistence observed with tocilizumab.

Interleukin-6 in juvenile idiopathic arthritis

Juvenile idiopathic arthritis (JIA) is a chronic childhood arthritis. Its pathogenesis is very complicated, with the involvement of not only immune cells but various types of parenchymal cells, and is affected by both genetic and environmental predispositions. The clinical spectrum from inflammation to related conditions is largely mediated by cytokines including interleukin (IL)-6. Fluctuations in IL-6 and its related molecules can modulate the pathogenesis and the clinical presentation positively or negatively. The recent clinical impact of IL-6 blockade on JIA has begun a therapeutic paradigm shift. This review describes the characteristics of JIA, mainly focused on IL-6 with the current therapeutic perspective.