Safety of biologic therapies for the treatment of juvenile idiopathic arthritis

INTRODUCTION

The introduction of biological therapies opened a new era of treatment of juvenile idiopathic arthritis. After 15 years of experience with the first biologics for treatment of pediatric rheumatic disease, long-term safety effects are of great interest.

AREAS COVERED

This review summarizes published knowledge about safety aspects from clinical trials as well as from biologic registries in juvenile idiopathic arthritis patients. Beside infusion and injection reactions, the occurrence and aggravation of infections, the occurrence of a second autoimmune diseases, including uveitis, psoriasis, chronic inflammatory bowel disease, multiple sclerosis, diabetes mellitus, as well as cytopenias and the development of malignancies are major concerns regarding treatment with biologics.

EXPERT OPINION

The safety profiles of approved biologics, the TNF-α inhibitors etanercept and adalimumab, and the IL-6-inhibitor tocilizumab are highly acceptable. This conclusion is not easily expandable to the IL-1 inhibitor canakinumab as well as the T-cell-activation-inhibitor abatacept due to lack of experience; however, both have showed an excellent safety profile so far. An increase in knowledge about risk profiles in national and international collaborations, with national as well as international registries, is necessary.

Two-year Efficacy and Safety of Etanercept in Pediatric Patients with Extended Oligoarthritis, Enthesitis-related Arthritis, or Psoriatic Arthritis

Objective.

The main objective was to determine the 2-year clinical benefit and safety of etanercept (ETN) in children with the juvenile idiopathic arthritis (JIA) categories of extended oligoarthritis (eoJIA), enthesitis-related arthritis (ERA), or psoriatic arthritis (PsA).

Methods.

CLIPPER was a 96-week, phase IIIb, open-label, multicenter study. Patients with eoJIA, ERA, or PsA received ETN 0.8 mg/kg once weekly (50 mg max) for up to 96 weeks. The proportions of patients reaching the JIA American College of Rheumatology (ACR) 30/50/70/90/100 and inactive disease responses at Week 96 were calculated. Adverse events (AE) were collected throughout the study (intention-to-treat sample).

Results.

There were 127 patients (eoJIA n = 60, ERA n = 38, PsA n = 29) who received ≥ 1 dose of ETN. The mean disease duration was 31.6 (eoJIA), 23.0 (ERA), and 21.8 (PsA) months. At Week 96, JIA ACR 30/50/70/90/100/inactive disease responses (95% CI) were achieved by 84.3% (76.7, 90.1), 83.5% (75.8, 89.5), 78.7% (70.6, 85.5), 55.1% (46.0, 63.9), 45.7% (36.8, 54.7), and 27.6% (20.0, 36.2) of patients, respectively. The most common AE (no. events, events per 100 patient-yrs) overall were headache (23, 10.7), pyrexia (12, 5.6), and diarrhea (10, 4.6). The most common infections were upper respiratory tract infection (83, 38.6), pharyngitis (50, 23.2), gastroenteritis (22, 10.2), bronchitis (19, 8.8), and rhinitis (17, 7.9). No cases of malignancy, active tuberculosis, demyelinating disorders, or death were reported.

Conclusion.

Over 96 weeks of therapy, ETN demonstrated sustained efficacy at treating the clinical symptoms of all 3 JIA categories, with no major safety issues.

Uveitis Events During Adalimumab, Etanercept, and Methotrexate Therapy in Juvenile Idiopathic Arthritis: Data From the Biologics in Pediatric Rheumatology Registry

OBJECTIVE

Uveitis is a major extraarticular quality of life-restricting manifestation of juvenile idiopathic arthritis (JIA). The aim of the study is to describe the occurrence of uveitis in JIA patients receiving tumor necrosis factor inhibitors or methotrexate (MTX).

METHODS

Patients' characteristics, treatment, and the reported first occurrence of uveitis as an adverse event were searched in the Biologics in Pediatric Rheumatology Registry. The rates per exposed patients, exposure time, and time until event were calculated.

RESULTS

Uveitis was reported as an adverse event in 75 of 3,467 patients; 51 of 2,844 patients were receiving MTX, 37 of 1,700 patients were receiving etanercept, and 13 of 364 patients were receiving adalimumab. Patients with uveitis were younger (mean ± SD age 4.6 ± 4.2 versus 7.4 ± 4.5 years; P < 0.0001), more likely to be antinuclear antibody positive (69% versus 43%; odds ratio [OR] 2.7, P < 0.0001), and had extended oligoarticular JIA (OR 2.2, P = 0.0005). Patients with a uveitis diagnosis before starting treatment more often had a uveitis event (n = 28, 8.4%; OR 8.5, P < 0.0001), and more often received adalimumab (OR 2.15 [95% confidence interval 1.58-2.94], P < 0.0001). In 16 patients, a new uveitis event occurred: 11 while taking MTX (3.2 per 1,000 patient-years), 2 while taking etanercept monotherapy (1.9 per 1,000 patient-years), and 3 while taking etanercept and MTX combination (0.9 per 1,000 patient-years). A new uveitis event occurred early in the disease course after a median disease duration of 1.5 years (interquartile range [IQR] 1.3-3.8) while taking etanercept and 1.8 years (IQR 1.8-2.1) for the MTX cohort. A recurrent uveitis event was reported after a disease duration of 7.6 years (IQR 4.3-10.0) in the etanercept cohort and 4.8 years (IQR 1.0-5.8) in the MTX cohort. Univariate analysis showed that MTX, but not etanercept or adalimumab, led to a lower rate of uveitis.

CONCLUSION

Patients with a history of uveitis had higher risks for uveitis events while taking both etanercept and adalimumab. Methotrexate turned out to be protective. Few patients developed a first uveitis event while taking etanercept, while the rate is comparable to that with MTX. Uveitis may not be attributed to be an adverse drug reaction to etanercept.

A Randomized, Double-Blind, Placebo-Controlled Multicenter Study of Adalimumab in Pediatric Patients With Enthesitis-Related Arthritis

Objective

Enthesitis‐related arthritis (ERA) is a juvenile idiopathic arthritis (JIA) category, primarily affecting entheses and peripheral joints. This study evaluated efficacy, safety, and pharmacokinetics of adalimumab versus placebo in patients with ERA.

Methods

This is a phase III, multicenter, randomized double‐blind study in patients ages ≥6 to <18 years with ERA treated with adalimumab (24 mg/m², maximum dose 40 mg every other week) or placebo for 12 weeks, followed by up to 192 weeks of open‐label adalimumab. The primary end point was percent change from baseline in number of active joints with arthritis (AJC) at week 12. Samples were collected to determine adalimumab serum concentrations. Adverse events (AEs) were assessed throughout the study.

Results

Forty‐six patients were randomized (31 adalimumab/15 placebo). At baseline, mean age was 12.9 years, mean duration of ERA symptoms was 2.6 years, mean AJC was 7.8, and mean enthesitis count was 8.1. Mean percent change from baseline in AJC at week 12 was greater in the adalimumab group versus placebo (−62.6% versus −11.6%; P = 0.039). Most secondary variables favored adalimumab versus placebo at week 12. Treatment response further increased with continued adalimumab therapy through week 52. Mean steady‐state adalimumab serum concentrations were 7.5–11.8 μg/ml, similar to patients age ≥2 years with polyarticular JIA. AE rates were similar between placebo and adalimumab: any AE (53.3% versus 67.7%), serious AEs (0% versus 3.2%), and infectious AEs (20.0% versus 29.0%).

Conclusion

Adalimumab reduced signs and symptoms of ERA at week 12, with improvement sustained through week 52. The safety profile was consistent with previous adalimumab studies.

The role of synthetic drugs in the biologic era: therapeutic strategies for treating juvenile idiopathic arthritis

INTRODUCTION

Juvenile idiopathic arthritis is the most frequent chronic rheumatic disease in childhood. Synthetic disease modifying drugs (DMARDs) have been used in its treatment since the 1980s and have led to substantial improvement of quality of life and disease outcome. Recent pharmacological research has focused on newer medications, especially biologic agents.

AREAS COVERED

Synthetic DMARDS, especially methotrexate, rightfully remain the first-line treatment of most categories of juvenile arthritis, as attested by several international guidelines. A substantial body of evidence supports these medications, and recent research tries to clarify their optimal use in the clinical setting, both as monotherapy and in combination with biologics. In addition, new forms of synthetic DMARDs are in the research pipeline, or are already used for rheumatoid arthritis.

EXPERT OPINION

Methotrexate remains the preferred first-line medication for polyarticular arthritis, with leflunomide as a viable alternative in case of intolerance or toxicity, despite lack of approval in Europe and the US. Sulfasalazine and hydroxychloroquine are used only rarely in clinical practice, considered in combination with methotrexate if biologics are not available. New synthetic DMARDS are in the research pipeline for JIA, in the form of small molecules.

Methotrexate intolerance in oral and subcutaneous administration in patients with juvenile idiopathic arthritis: a cross-sectional, observational study

OBJECTIVES

Methotrexate (MTX) is the cornerstone disease-modifying anti-rheumatic drug (DMARD) in juvenile idiopathic arthritis (JIA). In Dutch patients, MTX intolerance occurred frequently and was associated with subcutaneous (SC) administration. The aim of this study was to assess the prevalence of MTX intolerance and its association with the route of administration in a German cohort of JIA patients.

METHODS

A cross-sectional study of JIA patients on MTX was performed. Primary outcome was MTX intolerance, which was determined using the validated Methotrexate Intolerance Severity Score (MISS) questionnaire. The prevalence of gastrointestinal adverse effects and MTX intolerance was compared between patients on MTX SC and MTX administered orally (PO).

RESULTS

Of 179 JIA patients on MTX, 73 (40.8%) were intolerant. The odds of MTX intolerance were higher in patients using MTX exclusively SC compared to exclusively PO (adjusted odds ratio 3.37 [95% confidence interval 1.19-10.0]). There was strong evidence that the former experienced more behavioural complaints (76.1% vs. 47.4%, p=0.001) and weak evidence that they experienced more abdominal pain after MTX intake (43.5% vs. 27.4%, p=0.056).

CONCLUSIONS

The prevalence of MTX intolerance was high and exclusively SC administration of MTX was associated with MTX intolerance and behavioural adverse effects. The prevalence of gastrointestinal adverse effects was at least as high as in patients on MTX PO. The frequently held assumption that SC causes fewer side effects than PO seems unwarranted. Definite answers about the differences between SC and PO administration with respect to safety and efficacy should be obtained by randomised trials.

The majority of newly diagnosed patients with juvenile idiopathic arthritis reach an inactive disease state within the first year of specialised care: data from a German inception cohort

Objective

To describe the disease characteristics of patients with juvenile idiopathic arthritis (JIA) included in an inception cohort, to analyse how many patients from each JIA category reach an inactive disease state within the first year of specialised care and to determine predictors for attaining inactive disease.

Methods

Patients with JIA were enrolled in this study at 11 large German paediatric rheumatology units within the first 12 months after diagnosis. Laboratory and clinical parameters such as JIA core criteria and data on the medication used were collected every 3 months. Non-parametric statistical testing was performed for the comparison of the JIA core criteria at follow-up. Generalised linear models were used to analyse differences in the rates at which inactive disease was reached and to determine potential predictors.

Results

Of the 695 patients with JIA included in this analysis, approximately 75% experienced a period of inactive disease under treatment with disease-modifying antirheumatic drugs and systemic steroids in most cases with systemic-onset JIA or polyarthritis at least once during the first 12 months in ICON. Significant improvements were observed in all JIA core criteria, in disease activity and in functional status from baseline to the 12-month follow-up. Younger age at onset, a shorter duration between symptom onset and diagnosis and a positive antinuclear antibody status increased the probability of attaining an inactive disease state.

Conclusions

The 12-month outcome of JIA was good under real-life conditions, with half of the patients having attained inactive disease with contemporary treatments. Since a short duration between symptom onset and diagnosis was correlated to a period of inactive disease, children suspected of having JIA should be transferred to specialised care as soon as possible.

Autoantibodies to Dense Fine Speckles in Pediatric Diseases and Controls

OBJECTIVE

Autoantibodies to the dense fine speckled 70 kDa antigen (DFS70) are reported to be more common in individuals who do not have an antinuclear antibody (ANA)-associated rheumatic disease (AARD) than in patients with AARD. The frequency of anti-DFS70 antibodies has been thoroughly studied in adult but not in pediatric populations. The primary objective of this observational study was to determine the frequency of anti-DFS70 in pediatric AARD and reference cohorts.

METHODS

Sera from 743 children with AARD and related conditions, and 345 samples from reference cohorts (healthy children and those being investigated for AARD) were studied for anti-DFS70 autoantibodies as measured by a chemiluminescence immunoassay. A de-identified administrative database was used to retrieve demographic, serologic, and clinical data.

RESULTS

Anti-DFS70 antibodies were seen in 2.1% of healthy children and in 4.5% of sera from pediatric individuals referred for ANA testing. The frequency of anti-DFS70 was highest in juvenile localized scleroderma (LS; 4/29, 13.8%), juvenile dermatomyositis (JDM; 2/11, 18.2%), childhood systemic lupus erythematosus (cSLE; 19/331, 5.7%), diffuse cutaneous systemic sclerosis (1/22, 4.5%), celiac disease (2/49, 4.1%), and juvenile idiopathic arthritis (JIA; 5/202, 2.5%). Of note, anti-DFS70 antibodies were observed in 3/26 children (11.5%) with uveitis and JIA-associated uveitis.

CONCLUSION

The frequency of anti-DFS70 autoantibodies in healthy pediatric subjects is within the lower range of that reported in adults. Anti-DFS70 antibodies can be found in childhood SSc and cSLE, but has a remarkably high frequency in children with LS, JDM, and uveitis.

Efficacy and safety of etanercept in patients with the enthesitis-related arthritis category of juvenile idiopathic arthritis: results from a phase III randomized, double-blind study

OBJECTIVE

To evaluate the efficacy and safety of etanercept in patients with enthesitis-related arthritis (ERA) in juvenile idiopathic arthritis (JIA).

METHODS

This was a 2-phase study in JIA patients with active, refractory ERA. Phase I was an open-label, uncontrolled 24-week study period in which all patients were administered etanercept. Patients considered to be treatment responders at week 24 according to the American College of Rheumatology (ACR) Pediatric 30 (Pedi 30) criteria for improvement in juvenile arthritis entered the second phase, a 24-week randomized, double-blind, placebo-controlled withdrawal study, for an additional 24 weeks, for evaluation of the primary end point, occurrence of a disease flare from week 24 to week 48, based on the ACR preliminary definition of disease flare in juvenile arthritis.

RESULTS

Forty-one patients were enrolled. At week 24, treatment with etanercept resulted in response rates of 93%, 93%, 80%, 56%, and 54% based on the ACR Pedi 30, Pedi 50, Pedi 70, Pedi 90, and Pedi 100 criteria, respectively. In addition, a marked decrease in all disease activity measures was observed. The mean number of tender joints, swollen joints, and joints with active arthritis decreased by 91%, 97%, and 94%, respectively. Physician's global assessment of disease activity, parent's assessment of patient's overall well-being, and the Childhood Health Assessment Questionnaire disability index improved by 91%, 80%, and 86%, respectively. The number of tender enthesis sites and total scores for back pain, nocturnal pain, Bath Ankylosing Spondylitis Disease Activity Index, Bath Ankylosing Spondylitis Functional Index, and Juvenile Arthritis Disease Activity Score based on 10-joint counts (JADAS10) decreased by 75%, 72%, 81%, 72%, 85%, and 87%, respectively. In phase II, 38 patients were randomly assigned to receive placebo (n = 18) or to continue receiving etanercept (n = 20). Up to week 48, 12 disease flares occurred, in 9 patients receiving placebo and 3 patients receiving etanercept (odds ratio 6.0, P = 0.02). There were no serious infections, malignancies, or deaths.

CONCLUSION

In this study of patients with the ERA category of JIA, etanercept proved effective, as indicated by high ACR Pedi response rates and JADAS10 response rates at week 24. Patients who continued treatment with etanercept had significantly fewer flares than those who received placebo, although 50% of patients in the placebo group did not experience a flare. Treatment suspension may be a consideration for patients with the ERA category of JIA who achieve remission.

Inflammatory Bowel Disease in Juvenile Idiopathic Arthritis Patients Treated with Biologics

Objective.

Evolving inflammatory bowel disease (IBD) is a matter of interest in patients with juvenile idiopathic arthritis (JIA) and might be associated with JIA therapy.

Methods.

Data from the German biologics registry (Biologika in der Kinderrheumatologie; BiKeR) from 2001 to 2013 were analyzed.

Results.

There were 3071 patients with 8389 patient-years (PY) of observation followed. IBD was diagnosed in 11 patients, 8 with Crohn disease and 3 with ulcerative colitis. IBD incidence in patients with JIA was 1.31/1000 PY and higher than published IBD incidences in pediatric populations. Compared with the total BiKeR cohort, patients with IBD more commonly had enthesitis-related arthritis, extended oligoarthritis, psoriatic arthritis, and also rheumatoid factor (RF)-negative polyarthritis. No IBD occurred in patients with systemic JIA or RF-positive polyarthritis. In patients treated with methotrexate (MTX), the IBD incidence was significantly lower compared with patients not treated with MTX. Etanercept (ETN) monotherapy, but not the combination of ETN and MTX, was associated with an increased incidence of IBD.

Conclusion.

Incidence of IBD in patients with JIA is higher than in the population. MTX turned out to be protective, even in combination with ETN.

Characteristics and outcomes of chronic non-bacterial osteitis in children

OBJECTIVE

To determine patient characteristics, clinical presentation, pattern of involvement, treatment, and outcome of patients with chronic non-bacterial osteitis (CNO).

MATERIAL AND METHODS

Consecutive cases of CNO were analyzed at a single center for pediatrics and adolescent medicine from 2006 to 2013 in terms of patient characteristics, clinical presentation, pattern of involvement, treatment, and outcome.

RESULTS

We identified 32 children aged 1.5-15 years who were diagnosed with CNO between 2006 and 2013. A maximum of 12 bones per patient were affected in a total of 114 documented locations. The pelvis and clavicle (affecting 34% of patients each) were the most frequently affected bones. The foot skeleton was the most commonly affected region in 60% of patients. Skin manifestations were found in 7 (21%) patient. Increased inflammatory signs at presentation were detected in 18 patients. Pathological findings were found in all 30 children examined using magnetic resonance imaging (MRI), in 10 of 11 children examined using radiography, and in 8 of 10 patients examined using skeletal scintigraphy. Bone biopsy was performed in 9 patients. For initial treatment, non-steroidal anti-inflammatory drugs (NSAIDs) or coxibs were used in 28 (87.5%) patients. Remission or satisfactory follow-up was achieved in all patients.

CONCLUSION

Today, CNO is increasingly diagnosed using MRI and rarely through histological examinations. Therapeutic strategies include NSAIDs, which are often highly effective. All patients in the present study showed good clinical outcomes.

MRP8/14 serum levels as a predictor of response to starting and stopping anti-TNF treatment in juvenile idiopathic arthritis

Introduction

Approximately 30 % of juvenile idiopathic arthritis (JIA) patients fail to respond to anti-TNF treatment. When clinical remission is induced, some patients relapse after treatment has been stopped. We tested the predictive value of MRP8/14 serum levels to identify responders to treatment and relapse after discontinuation of therapy.

Methods

Samples from 88 non-systemic JIA patients who started and 26 patients who discontinued TNF-blockers were analyzed. MRP8/14 serum levels were measured by in-house MRP8/14 ELISA and by Bühlmann Calprotectin ELISA at start of anti-TNF treatment, within 6 months after start and at discontinuation of etanercept in clinical remission. Patients were categorized into responders (ACRpedi ≥ 50 and/or inactive disease) and non-responders (ACRpedi < 50) within six months after start, response was evaluated by change in JADAS-10. Disease activity was assessed within six months after discontinuation.

Results

Baseline MRP8/14 levels were higher in responders (median MRP8/14 of 1466 ng/ml (IQR 1045–3170)) compared to non-responders (median MRP8/14 of 812 (IQR 570–1178), p < 0.001). Levels decreased after start of treatment only in responders (p < 0.001). Change in JADAS-10 was correlated with baseline MRP8/14 levels (Spearman’s rho 0.361, p = 0.001). Patients who flared within 6 months after treatment discontinuation had higher MRP8/14 levels (p = 0.031, median 1025 ng/ml (IQR 588–1288)) compared to patients with stable remission (505 ng/ml (IQR 346–778)). Results were confirmed by Bühlmann ELISA with high reproducibility but different overall levels.

Conclusion

High levels of baseline MRP8/14 are associated with good response to anti-TNF treatment, whereas elevated MRP8/14 levels at discontinuation of etanercept are associated with higher chance to flare.

Electronic supplementary material

The online version of this article (doi:10.1186/s13075-015-0723-1) contains supplementary material, which is available to authorized users.