Methotrexate for juvenile idiopathic arthritis.

BACKGROUND: Juvenile idiopathic arthritis (JIA) is the most common rheumatic disease in childhood. Methotrexate has broad immunomodulatory properties and is the most commonly used disease-modifying antirheumatic drug (DMARD). This is an update of a 2001 Cochrane review. It supports a living guideline for children and young people with JIA. OBJECTIVES: To assess the benefits and harms of methotrexate for children and young people with juvenile idiopathic arthritis. SEARCH METHODS: The Australian JIA Living Guideline Working Group created a registry of all randomised controlled trials (RCTs) of JIA by searching CENTRAL, MEDLINE, Embase, and trials registries. The date of the most recent search of online databases was 1 February 2023. SELECTION CRITERIA: We searched for RCTs that compared methotrexate with placebo, no treatment, or another DMARD (with or without concomitant therapies) in children and young people (aged up to 18 years) with JIA. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methods. The main comparison was methotrexate versus placebo. Our outcomes were treatment response, sustained clinically inactive disease, function, pain, participant global assessment of well-being, serious adverse events, and withdrawals due to adverse events. We used GRADE to assess the certainty of evidence for each outcome. MAIN RESULTS: We identified three new trials in this update, bringing the total number of included RCTs to five (575 participants). Three trials evaluated oral methotrexate versus placebo, one evaluated methotrexate plus intra-articular glucocorticoid (IAGC) therapy versus IAGC therapy alone, and one evaluated methotrexate versus leflunomide. Doses of methotrexate ranged from 5 mg/m2/week to 15 mg/m2/week in four trials, and participants in the methotrexate group of the remaining trial received 0.5 mg/kg/week. Trial size varied from 31 to 226 participants. The average age of participants ranged from four to 10 years. Most participants were females and most had nonsystemic JIA. The study that evaluated methotrexate plus IAGC therapy versus IAGC therapy alone recruited children and young people with the oligoarticular disease subtype of JIA. Two placebo-controlled trials and the trial of methotrexate versus leflunomide were adequately randomised and blinded, and likely not susceptible to important biases. One placebo-controlled trial may have been susceptible to selection bias due to lack of adequate reporting of randomisation methods. The trial investigating the addition of methotrexate to IAGC therapy was susceptible to performance and detection biases. Methotrexate versus placebo Methotrexate compared with placebo may increase the number of children and young people who achieve treatment response up to six months (absolute difference of 163 more per 1000 people; risk ratio (RR) 1.67, 95% confidence interval (CI) 1.21 to 2.31; I2 = 0%; 3 trials, 328 participants; low-certainty evidence). However, methotrexate compared with placebo may have little or no effect on pain as measured on an increasing scale of 0 to 100 (mean difference (MD) -1.10 points, 95% CI -9.09 to 6.88; 1 trial, 114 participants), improvement in participant global assessment of well-being (absolute difference of 92 more per 1000 people; RR 1.23, 95% CI 0.88 to 1.72; 1 trial, 176 participants), occurrence of serious adverse events (absolute difference of 5 fewer per 1000 people; RR 0.63, 95% CI 0.04 to 8.97; 3 trials, 328 participants), and withdrawals due to adverse events (RR 3.46, 95% CI 0.60 to 19.79; 3 trials, 328 participants) up to six months. We could not estimate the absolute difference for withdrawals due to adverse events because there were no withdrawals in the placebo group. All outcomes were reported within six months of randomisation. We downgraded the certainty of the evidence to low for all outcomes due to indirectness (suboptimal dosing of methotrexate and diverse outcome measures) and imprecision (few participants and low event rates). No trials reported function or the number of participants with sustained clinically inactive disease. Serious adverse events included liver derangement, abdominal pain, and inadvertent overdose. Methotrexate plus intra-articular corticosteroid therapy versus intra-articular corticosteroid therapy alone Methotrexate plus IAGC therapy compared with IAGC therapy alone may have little or no effect on the probability of sustained clinically inactive disease or the rate of withdrawals due to adverse events up to 12 months in children and young people with the oligoarticular subtype of JIA (low-certainty evidence). We could not calculate the absolute difference in withdrawals due to adverse events because there were no withdrawals in the control group. We are uncertain if there is any difference between the interventions in the risk of severe adverse events, because none were reported. The study did not report treatment response, function, pain, or participant global assessment of well-being. Methotrexate versus an alternative disease-modifying antirheumatic drug Methotrexate compared with leflunomide may have little or no effect on the probability of treatment response or on function, participant global assessment of well-being, risk of serious adverse events, and rate of withdrawals due to adverse events up to four months. We downgraded the certainty of the evidence for all outcomes to low due to imprecision. The study did not report pain or sustained clinically inactive disease. AUTHORS' CONCLUSIONS: Oral methotrexate (5 mg/m2/week to 15 mg/m2/week) compared with placebo may increase the number of children and young people achieving treatment response but may have little or no effect on pain or participant global assessment of well-being. Oral methotrexate plus IAGC injections compared to IAGC injections alone may have little or no effect on the likelihood of sustained clinically inactive disease among children and young people with oligoarticular JIA. Similarly, methotrexate compared with leflunomide may have little or no effect on treatment response, function, and participant global assessment of well-being. Serious adverse events due to methotrexate appear to be rare. We will update this review as new evidence becomes available to inform the living guideline.

Abatacept as Monotherapy and in Combination With Methotrexate in Patients With Juvenile Idiopathic Arthritis: Analysis of 2 Phase III Trials.

OBJECTIVE: To describe the efficacy and safety data of children with polyarticular-course juvenile idiopathic arthritis (pcJIA) treated with abatacept (ABA) + methotrexate (MTX) or ABA monotherapy when prior MTX use was either ineffective or not tolerated. METHODS: Posthoc analysis of 2 phase III trials of subcutaneous (SC) and intravenous (IV) ABA over 2 years in patients with pcJIA (aged 2-17 years). Patients were stratified by treatment with ABA + MTX or ABA monotherapy and further by prior biologic use. Efficacy outcomes included JIA-American College of Rheumatology (JIA-ACR) responses, Juvenile Arthritis Disease Activity Score in 27 joints using C-reactive protein (JADAS27-CRP), and safety. Descriptive pharmacokinetic analyses were also performed. RESULTS: Efficacy responses (JIA-ACR and JADAS27-CRP) were similar between patients receiving ABA + MTX (n = 310) or ABA monotherapy (n = 99) and persisted over 2 years. Clinical response rates were similar in biologic-naïve patients and prior biologic users; this was independent of MTX use. Across both studies, ABA + MTX and ABA monotherapy displayed similar safety profiles. Pharmacokinetic results revealed similar minimum steady-state trough ABA concentrations between studies. Further, baseline MTX did not influence ABA clearance and was not a significant predictor of JIA-ACR responses. CONCLUSION: ABA monotherapy (SC and IV) was effective and well tolerated in children with pcJIA when prior MTX use was ineffective or not tolerated. Treatment effects of ABA appear to be independent of MTX coadministration. Consequently, ABA monotherapy can be considered for those with prior biologic therapy if MTX use is inappropriate. (ClinicalTrials.gov: NCT01844518 and NCT00095173).

Treatment Response to Tumor Necrosis Factor Inhibitors and Methotrexate Monotherapy in Adults With Juvenile Idiopathic Arthritis: Data From NOR-DMARD.

OBJECTIVE: To compare the effectiveness of tumor necrosis factor inhibitors (TNFi) ± comedication and methotrexate (MTX) monotherapy between patients with adult juvenile idiopathic arthritis (JIA) and patients with rheumatoid arthritis (RA). METHODS: Adult patients with JIA and RA were identified from the Norwegian Antirheumatic Drug Register (NOR-DMARD) register. Disease activity measurements at baseline, 3, 6, and 12 months were compared between patients with JIA and RA starting (1) TNFi and (2) MTX monotherapy, using age- and gender-weighted analyses. We calculated differences between JIA and RA in mean changes in Disease Activity Score in 28 joints (DAS28), Clinical Disease Activity Index (CDAI), and Simplified Disease Activity Index (SDAI), among other disease activity measures. DAS28, CDAI, SDAI, and American College of Rheumatology (ACR)/European Alliance of Associations for Rheumatology (EULAR) remission rates at 3, 6, and 12 months, as well as 6- and 12-month Lund Efficacy Index (LUNDEX)-corrected rates, were calculated. RESULTS: We identified 478 patients with JIA (TNFi/MTX monotherapy, n = 358/120) and 4637 patients with RA (TNFi/MTX monotherapy, n = 2292/2345). Patients with JIA had lower baseline disease activity compared to patients with RA across treatment groups. After baseline disease activity adjustment, there were no significant differences in disease activity change from baseline to 3, 6, and 12-months of follow-up between patients with JIA and RA for either treatment group. Twelve-month remission rates were similar between groups based on DAS28 (TNFi: JIA 55.2%, RA 49.5%; MTX monotherapy: JIA 45.3%, RA 41.2%) and ACR/EULAR remission criteria (TNFi: JIA 20.4%, RA 20%; MTX monotherapy: JIA 17%, RA 12.7%). Median drug survival (yrs) was similar for JIA and RA in both treatment groups (TNFi: JIA 1.2, RA 1.4; MTX monotherapy: JIA 1.3, RA 1.6). CONCLUSION: TNFi and MTX monotherapy are effective in adult JIA, with similar effectiveness to that shown in RA.

[Biological therapy in juvenile idiopathic arthritis].

During the past 20 years of the biologic era, remission has become a realistic goal when treating children and adolescents with juvenile idiopathic arthritis (JIA). Studies describing long-term effects and safety are now available for several biologic agents, overall being well tolerated and with acceptable adverse events. No significant association between treatment with biologics and malignancy has been detected. This review finds that although biologics have been a success for most JIA patients, some fail to respond leaving the need for new treatment options and optimal switching between biologics most relevant.

Efficacy and Toxicity of Pembrolizumab in Pediatric Metastatic Recurrent Melanoma.

BACKGROUND/AIM: Malignant melanoma is a rare disease in the pediatric population and there are no recommendations regarding its management in children, while the current standard of care in metastatic or unresectable melanoma in adult patients includes immunotherapy (anti-CTLA-4 and anti-PD-1 antibodies). Advances in the management of adults with melanoma offer the prospect of promising therapeutic options for children. CASE REPORT: We describe a case of a 7-year-old patient with recurrent metastatic melanoma, for whom pembrolizumab was used as an adjuvant therapy on compassionate use basis. CONCLUSION: Due to adverse events, the treatment was discontinued after 5 months of pembrolizumab, but with 12-months of follow-up, patient remains in complete remission.

Predictors of Flare Following Etanercept Withdrawal in Patients with Rheumatoid Factor-negative Juvenile Idiopathic Arthritis Who Reached Remission while Taking Medication.

OBJECTIVE: To evaluate the rate of flare after etanercept (ETN) withdrawal in patients with juvenile idiopathic arthritis (JIA) who attained clinical remission while taking medication, and to identify predictors of flare. METHODS: Patients were included with oligo- (oJIA) and rheumatoid factor-negative polyarticular JIA (pJIA) who received a first course of ETN for at least 18 months, maintained clinically inactive disease (CID) for at least 6 months during treatment, and were followed for 12 months after ETN withdrawal. Demographic and clinical features were collected at onset, at baseline (initiation of ETN), and at time of disease flare. RESULTS: After ETN withdrawal, 66 of the 110 patients enrolled (60%) flared with arthritis (of whom 7 flared with concurrent anterior uveitis; none with uveitis alone). The median time to flare was 4.3 months (interquartile range 2.5-6.4) with no evident differences between oJIA and pJIA. The number and type of joints involved at baseline and characteristics of ETN treatment/discontinuation were not associated with flare. Patients who flared were more frequently males (p = 0.034), positive for antinuclear antibody (ANA; p = 0.047), and had higher values of C-reactive protein (CRP; p = 0.012) at baseline. These variables remained significantly associated with flare in a multivariate logistic analysis, a model accounting for only 14% of the variability of the occurrence of the flare. CONCLUSION: Our results show that a significant proportion of patients with JIA who maintain CID for at least 6 months experience a relapse after ETN withdrawal. Male sex, presence of ANA, and elevated CRP at baseline were associated with higher risk of flare.

Systemic onset juvenile idiopathic arthritis and exposure to fine particulate air pollution.

OBJECTIVES: Fine particulate matter (PM2.5) is a measurable component of ambient pollution, and positive associations of short-term PM2.5 exposure with the clinical presentation of systemic onset juvenile idiopathic arthritis (SJIA) in young children have been described in a regional cohort. Our objective was to further establish associations between short-term pollution exposures and the reported clinical event of SJIA onset in cases residing from multiple metropolitan regions. METHODS: A case-crossover study design was used to analyse associations of short-term PM2.5 exposures with the event of SJIA symptom onset from cases residing in five metropolitan regions. Time trends, seasonality, month, and weekday were controlled for by matching. Selected exposure windows (to 14 days) of PM2.5 were examined. RESULTS: Positive, statistically significant associations between PM2.5 concentrations and elevated risk of SJIA were not observed. The most positive associations of short-term PM2.5 exposure with SJIA were in children <5.5 years (RR 1.75, 95% CI 0.85-3.62). An ad hoc extended pooled analysis including previously reported cases from Utah's metropolitan areas identified an increased risk of SJIA for children <5.5 years (RR = 1.76, 95% CI 1.07-2.89 per 10 µg/m3 increase in 3-day lagged moving average PM2.5). CONCLUSIONS: In this multi-city, multi-period study small, statistically insignificant PM2.5-SJIA associations are observed. However, as found in prior study, the PM2.5-SJIA association is most suggestive in preschool aged children. Larger numbers of SJIA cases spatially located in geographic areas which experience a greater day to day ambient particulate burden may be required by the analysis to demonstrate effects.

Antibiotic Exposure and Juvenile Idiopathic Arthritis: A Case-Control Study.

BACKGROUND AND OBJECTIVE: Recent evidence has linked childhood antibiotic use and microbiome disturbance to autoimmune conditions. This study tested the hypothesis that antibiotic exposure was associated with newly diagnosed juvenile idiopathic arthritis (JIA). METHODS: We performed a nested case-control study in a population-representative medical records database from the United Kingdom. Children with newly diagnosed JIA were compared with age- and gender-matched control subjects randomly selected from general practices containing at least 1 case, excluding those with inflammatory bowel disease, immunodeficiency, or other systemic rheumatic diseases. Conditional logistic regression was used to examine the association between antibacterial antibiotics (including number of antibiotic courses and timing) and JIA after adjusting for significant confounders. RESULTS: Any antibiotic exposure was associated with an increased rate of developing JIA (adjusted odds ratio: 2.1 [95% confidence interval: 1.2-3.5]). This relationship was dose dependent (adjusted odds ratio over 5 antibiotic courses: 3.0 [95% confidence interval: 1.6-5.6]), strongest for exposures within 1 year of diagnosis, and did not substantively change when adjusting for number or type of infections. In contrast, nonbacterial antimicrobial agents (eg, antifungal, antiviral) were not associated with JIA. In addition, antibiotic-treated upper respiratory tract infections were more strongly associated with JIA than untreated upper respiratory tract infections. CONCLUSIONS: Antibiotics were associated with newly diagnosed JIA in a dose- and time-dependent fashion in a large pediatric population. Antibiotic exposure may play a role in JIA pathogenesis, perhaps mediated through alterations in the microbiome.

Systemic juvenile idiopathic arthritis-like syndrome in mice following stimulation of the immune system with Freund's complete adjuvant: regulation by interferon-γ.

OBJECTIVE: Systemic juvenile idiopathic arthritis (JIA) is unique among the rheumatic diseases of childhood, given its distinctive systemic inflammatory character. Inappropriate control of innate immune responses following an initially harmless trigger is thought to account for the excessive inflammatory reaction. The aim of this study was to generate a similar systemic inflammatory syndrome in mice by injecting a relatively innocuous, yet persistent, immune system trigger: Freund's complete adjuvant (CFA), containing heat-killed mycobacteria. METHODS: Given the central role of interferon-γ (IFNγ) in immune regulation, we challenged wild-type (WT) and IFNγ-knockout (KO) BALB/c mice with CFA, and analyzed their clinical symptoms and biologic characteristics. The production of cytokines and the effects of anticytokine antibodies were investigated. RESULTS: In WT mice, CFA injection resulted in splenomegaly, lymphadenopathy, neutrophilia, thrombocytosis, and increased cytokine expression. In the absence of IFNγ, these symptoms were more pronounced and were accompanied by weight loss, arthritis, anemia, hemophagocytosis, abundance of immature blood cells, and increased levels of interleukin-6 (IL-6), all of which are reminiscent of the symptoms of systemic JIA. CFA-challenged IFNγ-KO mice showed increased expression of IL-17 by CD4+ T cells and by innate γ/δ T cells. Inflammatory and hematologic changes were prevented by treatment with anti-IL-12/IL-23p40 and anti-IL-17 antibodies. CONCLUSION: Immune stimulation of IFNγ-KO mice with CFA produces a systemic inflammatory syndrome reflecting the clinical, biologic, and histopathologic picture of systemic JIA. The protective function of IFNγ in preventing anemia and overall systemic inflammation is a striking observation. The finding that both adaptive and innate T cells are important sources of IL-17 may be of relevance in the pathogenesis of systemic JIA.

Predisposing factors in sulphasalazine-induced systemic lupus erythematosus.

The aim of this study was to define predisposing factors in patients with sulphasalazine-induced systemic lupus erythematosus (SLE). Eleven patients with onset of SLE or SLE-like syndromes during sulphasalazine treatment are reported. Before the onset of SLE, five of the patients suffered from rheumatoid arthritis (RA), one from psoriatic arthropathy (PsoA), two from juvenile chronic arthritis (JCA) and three from ulcerative colitis (UC). At the time of diagnosis of drug-induced SLE, analysis of antinuclear antibodies (ANA), anti-double-stranded DNA antibodies (anti-dsDNA), anti-histone antibodies (anti-histones), acetylator status of the enzyme N-acetyltransferase 2 (NAT2) and HLA classification were performed. All patients were anti-DNA positive at disease onset and were determined to be slow acetylators. HLA A1 occurred in 4/10 patients, B8 in 5/10. HLA DR 3 was represented in one patient and DR 3(17) in five patients. The DQA1* 0501 allele was observed in 7/10 patients and DQB1 0201* in 6/10. Persistent SLE and development of nephritis were noted in patients with long duration of treatment and high cumulative dose of sulphasalazine (> 1000 g). In sulphasalazine-induced SLE, slow acetylator genotype and HLA haplotypes associated with idiopathic SLE seem to predict disease induction. Further, as the risk of developing persistent SLE and nephritis increases with long-standing sulphasalazine medication, it is of importance to monitor the patients with regard to signs of SLE during the entire treatment period.

Microcirculation of the juvenile knee in chronic arthritis.

In order to investigate pathogenetic factors in growth abnormalities of the knee in hemophilic arthropathy and juvenile rheumatoid arthritis, the hemodynamic changes of the knee following chronic synovial inflammation and elevated joint pressure were studied in puppies. Unilateral arthritis was induced by intraarticular injections of carrageenan solution. Regional blood flow (RBF) was measured by tracer microsphere technique. Microvascular volume (VV) was estimated from the distribution volumes of Cr51-labelled erythrocytes and I125 fibrinogen. Mean transit times (TT) of blood components were calculated from volume/flow ratios. The arthritic joint capsules were characterized by high RBF rates, increased VV, low tissue hematocrit (HCT) and short TT of blood. In the juxtaarticular epiphyses and the patella, RBF was largely unchanged, whereas VV was significantly elevated and TT of blood prolonged. The growth plates formed borders for the extension of these changes. The increased permeability and surface area between blood and bone in arthritis may accelerate the resorption and subsequent destruction of subchondral bone in chronic arthropathies of the juvenile knee.