Outcomes after anti-tumour necrosis factor originator to biosimilar switching in children and young people with juvenile idiopathic arthritis in the UK: a national cohort study.

BACKGROUND: For cost-saving purposes, children and young people with juvenile idiopathic arthritis (JIA) are being switched (for non-medical reasons) from biological originators to biosimilars. Here, we aimed to investigate those who switched from an anti-tumour necrosis factor (TNF) originator to a biosimilar, regarding drug survival and disease activity, compared with a matched cohort who continued the originator. METHODS: This analysis included all patients in the UK JIA Biologics Register switching directly from an anti-TNF originator to a biosimilar of the same product. All patients were matched (age, sex, disease duration, calendar year of when patients started originator therapy, line of therapy, and International League of Associations for Rheumatology [ILAR] category) to patients continuing the originator. For those matched successfully, a Cox proportional hazard model assessed whether drug persistence differed between those who switched compared with those who continued the originator. Overall change in the 71-joint juvenile arthritis disease activity score and the proportion of patients with a clinically important worsening score (by ≥1·7 units) after 6 months was compared between cohorts. This analysis was designed to address a priority research area set by our patient partners. FINDINGS: There were 224 children and young people with non-systemic JIA (139 [62%] were female, and 85 [38%] were male) identified as switching from a biological originator to a biosimilar of the same product from Jan 1, 2017, to July 7, 2023. 143 (64%) patients were originally on adalimumab, 56 (25%) on etanercept, and 25 (11%) on infliximab. Of these, 164 patients were matched successfully to those continuing the originator. There was no evidence that patients switching were more likely to stop treatment compared with those continuing the originator, with a hazard ratio of 1·46 (95% CI 0·93-2·30). Of the 51 patients in the biosimilar group who stopped treatment, 18 (35%) switched back to the originator (14 in the first year), 28 (55%) started a different biological drug, and five (10%) discontinued all treatment by the last follow-up. Of the 87 matched patients with available disease activity, there was no evidence that JADAS-71 worsened more after 6 months, with an odds ratio of 0·71 (95% CI 0·34-1·51; p=0·38). INTERPRETATION: In this matched comparative effectiveness analysis, children and young people with JIA switched from originators to biosimilars. Disease activity was similar between patients switching compared with those continuing the originator. Three quarters of patients were still receiving their biosimilar after 1 year, with switching back to originator uncommon, at only 9% after 1 year, suggesting good tolerability of non-medical switching in this patient population. This information is reassuring to clinicians and patients regarding the effect of non-medical biological switching. FUNDING: British Society for Rheumatology, Versus Arthritis, and National Institutes for Health Research Manchester Biomedical Research Centre.

Juvenile idiopathic arthritis: from aetiopathogenesis to therapeutic approaches.

Juvenile idiopathic arthritis (JIA) is the most common paediatric rheumatological disorder and is classified by subtype according to International League of Associations for Rheumatology criteria. Depending on the number of joints affected, presence of extra-articular manifestations, systemic symptoms, serology and genetic factors, JIA is divided into oligoarticular, polyarticular, systemic, psoriatic, enthesitis-related and undifferentiated arthritis. This review provides an overview of advances in understanding of JIA pathogenesis focusing on aetiology, histopathology, immunological changes associated with disease activity, and best treatment options. Greater understanding of JIA as a collective of complex inflammatory diseases is discussed within the context of therapeutic interventions, including traditional non-biologic and up-to-date biologic disease-modifying anti-rheumatic drugs. Whilst the advent of advanced therapeutics has improved clinical outcomes, a considerable number of patients remain unresponsive to treatment, emphasising the need for further understanding of disease progression and remission to support stratification of patients to treatment pathways.

Different corticosteroid induction regimens in children and young people with juvenile idiopathic arthritis: the SIRJIA mixed-methods feasibility study.

BACKGROUND: In the UK, juvenile idiopathic arthritis is the most common inflammatory disorder in childhood, affecting 10 : 100,000 children and young people aged < 16 years each year, with a population prevalence of around 1 : 1000. Corticosteroids are commonly used to treat juvenile idiopathic arthritis; however, there is currently a lack of consensus as to which corticosteroid induction regimen should be used with various disease subtypes and severities of juvenile idiopathic arthritis. OBJECTIVE: The main study objective was to determine the feasibility of conducting a randomised controlled trial to compare the different corticosteroid induction regimens in children and young people with juvenile idiopathic arthritis. DESIGN: This was a mixed-methods study. Work packages included a literature review; qualitative interviews with children and young people with juvenile idiopathic arthritis and their families; a questionnaire survey and screening log to establish current UK practice; a consensus meeting with health-care professionals, children and young people with juvenile idiopathic arthritis, and their families to establish the primary outcome; a feasibility study to pilot data capture and to collect data for future sample size calculations; and a final consensus meeting to establish the final protocol. SETTING: The setting was rheumatology clinics across the UK. PARTICIPANTS: Children, young people and their families who attended clinics and health-care professionals took part in this mixed-methods study. INTERVENTIONS: This study observed methods of prescribing corticosteroids across the UK. MAIN OUTCOME MEASURES: The main study outcomes were the acceptability of a future trial for children, young people, their families and health-care professionals, and the feasibility of delivering such a trial. RESULTS: Qualitative interviews identified differences in the views of children, young people and their families on a randomised controlled trial and potential barriers to recruitment. A total of 297 participants were screened from 13 centres in just less than 6 months. In practice, all routes of corticosteroid administration were used, and in all subtypes of juvenile idiopathic arthritis. Intra-articular corticosteroid injection was the most common treatment. The questionnaire surveys showed the varying clinical practice across the UK, but established intra-articular corticosteroids as the treatment control for a future trial. The primary outcome of choice for children, young people, their families and health-care professionals was the Juvenile Arthritis Disease Activity Score, 71-joint count. However, results from the feasibility study showed that, owing to missing blood test data, the clinical Juvenile Arthritis Disease Activity Score should be used. The Juvenile Arthritis Disease Activity Score, 71-joint count, and the clinical Juvenile Arthritis Disease Activity Score are composite disease activity scoring systems for juvenile arthritis. Two final trial protocols were established for a future randomised controlled trial. LIMITATIONS: Fewer clinics were included in this feasibility study than originally planned, limiting the ability to draw strong conclusions about these units to take part in future research. CONCLUSIONS: A definitive randomised controlled trial is likely to be feasible based on the findings from this study; however, important recommendations should be taken into account when planning such a trial. FUTURE WORK: This mixed-methods study has laid down the foundations to develop the evidence base in this area and conducting a randomised control trial to compare different corticosteroid induction regimens in children and young people with juvenile idiopathic arthritis is likely to be feasible. STUDY REGISTRATION: Current Controlled Trials ISRCTN16649996. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 24, No. 36. See the NIHR Journals Library website for further project information.

ABOUT JUVENILE IDIOPATHIC ARTHRITIS: Juvenile idiopathic arthritis refers to a group of conditions that cause inflammation and damage of the joints, starting in children and young people aged < 16 years. Treatments include anti-inflammatory medicines, disease-modifying/biologic medicines and corticosteroids. Young people often require corticosteroids at the start of their treatment, or in a flare with worsening inflammation, to get their juvenile idiopathic arthritis under control. A short course of corticosteroids can help and can be given by injection into the joint, through a drip into a vein, by injection into the muscle or in the form of tablets or liquid to be taken orally. Although they have been used for decades, there is no research to show the best way(s) of giving corticosteroids. STUDY AIMS: The study aimed to (1) agree on what corticosteroid treatments to compare in a treatment trial and the best way to measure changes in juvenile idiopathic arthritis to evaluate a quick-acting treatment and (2) find out if there are enough young people with active juvenile idiopathic arthritis in the UK to be included in such a study. METHODS: Published research on corticosteroids in juvenile idiopathic arthritis was reviewed. Health-care professionals were asked how they choose which corticosteroids to use and which method of administration to use. Interviews were carried out with children and young people and their families to (1) consider the design of a study comparing corticosteroid routes, (2) identify outcomes important to them and (3) determine whether or not they would be willing to take part in a future study. A 3-month feasibility study was carried out to collect details of children and young people with active juvenile idiopathic arthritis before and after corticosteroid treatment to measure improvements in juvenile idiopathic arthritis activity, and to see whether or not a larger study would be possible. FINDINGS: This study showed that corticosteroids are used in different ways across the UK. The views of children, young people and their families must be taken into account when designing a future study. This study calculated the number of young people who would be needed to take part in the future, showing that it would be possible to do a larger study that compared different corticosteroid treatments, which would help everyone to understand the best way to use corticosteroids.

The association between low socioeconomic status with high physical limitations and low illness self-perception in patients with juvenile idiopathic arthritis: results from the Childhood Arthritis Prospective Study.

OBJECTIVE: To examine the association between socioeconomic status (SES) and delay to a pediatric rheumatology clinic, disease severity, and illness perception in patients with juvenile idiopathic arthritis in England. METHODS: Using the Index of Multiple Deprivation, 923 consecutive children from the Childhood Arthritis Prospective Study were assigned to SES groups: high-SES (19.1%), middle-SES (44.5%), or low-SES (36.4%). At baseline, disease activity was assessed, and the Childhood Health Assessment Questionnaire (C-HAQ), the Illness Perception Questionnaire, and the Child Health Questionnaire, version Parent Form 50, were completed. Linear median regression analyses or zero-inflated negative binominal (ZINB) regression analyses were used. RESULTS: Delay to first pediatric rheumatology consultation was the same between the 3 SES groups. Although disease activity scores assessed by the pediatric rheumatologist did not differ between the 3 SES groups, persons in the low-SES group recorded higher C-HAQ scores compared to the high-SES group (zero-inflated part of ZINB odds ratio 0.28 [95% confidence interval (95% CI) 0.14, 0.55], count part of ZINB ß 0.26 [95% CI 0.05, 0.48]). Parents with low SES also reported more often that their children's school work or activities with friends had been limited. Furthermore, the low-SES group had a worse perception about the consequences of the disease and the effect of treatment than those in the high-SES group. CONCLUSION: Patients from a low-SES background report more problems with daily activities and have a lower perception of the consequences of the disease than patients from a high-SES background, warranting special attention from a multidisciplinary team.

Agreement between proxy and adolescent assessment of disability, pain, and well-being in juvenile idiopathic arthritis.

OBJECTIVES: Adolescents with juvenile idiopathic arthritis have demonstrated substantial disagreement with their proxy's assessment of their disability, pain, and well-being. Our objective was to describe the clinical and psychological factors associated with discordance. STUDY DESIGN: This analysis included 204 proxy-adolescent (median age, 13 years) dyads that completed a Childhood Health Assessment Questionnaire for disability with 100-mm visual analogue scales for pain and well-being. Depressive symptoms in adolescents were measured by the Mood and Feelings Questionnaire and in proxies the General Health Questionnaire. Disagreement was assessed using Bland-Altman plots. Associations with discordance were identified using logistic regression analyses. RESULTS: There was higher agreement for disability (84%) than for pain (71%) and well-being (66%). Regression analyses found no association between age, sex, or disease duration and disagreement. However, relationships between disease activity and disagreement in outcomes were identified. Independent associations were found between increasing Mood and Feelings Questionnaire scores and disagreement in pain and well-being. CONCLUSIONS: Proxy and adolescent reports of pain and well-being are more likely to disagree in those with severe disease. Adolescents who report depressive symptoms are also more likely to disagree with their proxy. The reasons for these are multifactorial, and considerations of both reports are important when assessing outcomes in juvenile idiopathic arthritis.