Case report: Breaking CNS immuno-privilege: TNFα-inhibitor triggers aseptic meningitis in a patient with rheumatoid arthritis.

Blood-brain barrier dysfunction might be driven by peripheral inflammation. TNFα inhibitors (TNF-αi) are occasionally associated with a wide spectrum of neurological immuno-mediated disorders. However, patients with systemic autoimmune disorders, including rheumatoid arthritis (RA), might be prone to develop further organ-specific, including central nervous system (CNS), autoimmunity. Here we report the case of a patient, affected by RA and treated with etanercept, who suddenly developed focal neurological symptoms. Cerebrospinal fluid, magnetic resonance imaging (MRI), and positron emission tomography (PET)/MRI findings are reported and support the diagnosis of TNF-αi -associated aseptic meningitis.

Ramsay Hunt Syndrome Associated With Etanercept Treatment for Rheumatoid Arthritis: A Case Report and a Review of Literature.

A 38-year-old woman with rheumatoid arthritis treated with etanercept presented with complaints of ear pain. Over four days, the pain progressed to a vesicular rash and then facial nerve paralysis. The patient was diagnosed with Ramsay Hunt syndrome (RHS), a reactivation of the varicella zoster virus that specifically affects the seventh cranial nerve (CN VII). Etanercept is an anti-tumor necrosis factor (anti-TNF) agent that has known immunosuppressive effects. RHS occurs more commonly in immunocompromised states, such as the one induced by etanercept. To the best of our knowledge, this is one of the first reported cases of RHS with etanercept treatment.

Perispinal etanercept stroke trial design: PESTO and beyond.

INTRODUCTION: Perispinal etanercept (PSE) is an innovative treatment designed to improve stroke recovery by addressing chronic post-stroke neuroinflammation. Basic science evidence, randomized clinical trial (RCT) evidence and 14 years of favorable clinical experience support the use of PSE to treat chronic stroke. This article provides guidance for the design of future PSE RCTs in accordance with current FDA recommendations. AREAS COVERED: Scientific background and essential elements of PSE RCT design. EXPERT OPINION: Intimate familiarity with PSE, its novel method of drug delivery, and the characteristics of ideal enriched study populations are necessary for those designing future PSE stroke trials. The design elements needed to enable a PSE RCT to generate valid results include a suitable research question; a homogeneous study population selected using a prospective enrichment strategy; a primary outcome measure responsive to the neurological improvements that result from PSE; trialists with expertise in perispinal delivery; optimal etanercept dosing; and steps taken to minimize the number of placebo responders. RCTs failing to incorporate these elements, such as the PESTO trial, are incapable of reaching reliable conclusions regarding PSE efficacy. SF-36 has not been validated in PSE trials and is unsuitable for use as a primary outcome measure in PSE RCTs.

Real-life data of etanercept efficacy and safety in juvenile idiopathic arthritis: a 24-month retrospective study at a single center.

OBJECTIVE: The aim of this study was to assess the efficacy and safety of etanercept (ETA) use in juvenile idiopathic arthritis (JIA). METHODS: The 24-month data of patients with JIA on etanercept in a single center were evaluated retrospectively. Response to treatment was assessed according to 10-joint Juvenile Arthritis Disease Activity Score (JADAS10), and JIA-American College of Rheumatology (ACR) improvement criteria. Safety assessments were based on adverse event (AE) reports. RESULTS: The study included 152 patients with JIA. The mean age at diagnosis of JIA was 8.5 ± 4.4 years, and treatment with ETA started at a mean age of 11.1 ± 4.4 years. The mean duration of ETA use was 16 ± 11.1 months. The mean JADAS10 score at baseline was 18.5 ± 5.9. By the third month, it had reduced to 8.6 ± 6.6 and by the sixth month to 5.7 ± 6. By the twelfth month, the JADAS10 score was 4.9 ± 6.7, and by the twenty-fourth month, it had worsened to 7.3 ± 7.8. ACR50 response was achieved in 79.6% of patients at 3 months, 67.1% at 6 months, 79.3% at twelfth months, 70.7% at the twenty-fourth month. During ETA treatment, 10 patients required hospitalization for serious infections. CONCLUSION: Etanercept is a safe and effective option for patients with JIA. However, variations in response between JIA subtypes highlight the need for individualized treatment strategies.

Effectiveness and Safety of Etanercept in Paediatric Patients with Plaque-Type Psoriasis: Real-World Evidence.

Background: Psoriasis is a chronic, multisystemic, inflammatory disease affecting approximately 1% of children and significantly reducing their health-related quality of life. Etanercept is a biologic fusion protein-blocking TNF-α and belongs to one of the biologics used among the children population. The purpose of this study was to assess the effectiveness and safety profile of etanercept in paediatric patients with plaque-type psoriasis. Material and methods: The outcome of the treatment was evaluated based on Psoriasis Area and Severity Index (PASI), Body Surface Area (BSA), and Children's Dermatology Life Quality Index (CDLQI). Achievement of at least PASI75 at week 16 was assessed as an adequate response to therapy, which was the primary endpoint. Results: Forty-three paediatric patients were included in the study, 24 females and 19 males. The average age at inclusion into our study was 13 years. At baseline, the mean PASI score, BSA, and CDLQI were 16.3 ± 6.5, 22.3 ± 12.2%, and 17.4 ± 5.3, respectively. At week 16, 90.7% of patients achieved PASI 50, 79.1% achieved PASI 75, and 46.5% attained PASI 90. There was also a decrease in mean BSA and CDLQI values to 3.5 ± 3.8 and 5.4 ± 5.7, respectively. Conclusions: Etanercept proved to be effective, safe, and well-tolerated among the paediatric population with psoriasis.

The Use of TNF-α Inhibitors in Active Ankylosing Spondylitis Treatment.

Ankylosing spondylitis (AS) is a challenging disease, characterized by chronic inflammation and structural damage primarily affecting the axial skeleton, while extra-articular manifestations may also appear. This results in the deterioration of patients' quality of life. Over the past few decades, tumor necrosis factor-α (TNF-α) inhibitors have revolutionized the management of AS, offering substantial relief from symptoms and improving patient outcomes. The aim of this review is to assess the efficacy of TNF-α inhibitors in patients with active AS. A search was performed in the PubMed database using the following keywords: ("TNF alpha inhibitors" OR "anti TNF-a" OR "TNF-a inhibitors" OR "anti TNF-alpha" OR "Etanercept " OR "Golimumab" OR "Infliximab" OR "Certolizumab pegol" OR "Adalimumab") AND "ankylosing spondylitis". The search was completed in February 2024, and 35 studies were included in this review following PRISMA guidelines. The findings reveal evidence supporting the efficacy of TNF-α inhibitors in reducing inflammation, preventing structural damage, and enhancing overall well-being in AS patients. Overall, TNF-α inhibitors have emerged as a cornerstone in the therapeutic algorithm against AS with a very satisfactory safety profile.

Pregnancy Recommendations Solely Based on Preclinical Evidence Should Be Integrated with Real-World Evidence: A Disproportionality Analysis of Certolizumab and Other TNF-Alpha Inhibitors Used in Pregnant Patients with Psoriasis.

Treatment for pregnant women with psoriasis is limited by the lack of information typically related to clinical trials. While anti-tumor necrosis factor (TNF) drugs offer therapeutic benefits, their safety during pregnancy is a concern. Notably, certolizumab is comparatively safer than adalimumab, etanercept, infliximab, and golimumab according to the current recommendations. Thus, this study aimed to conduct a pharmacovigilance comparative analysis of maternal and neonatal outcomes associated with certolizumab versus other anti-TNF drugs by using data from EudraVigilance. A descriptive analysis was performed of Individual Case Safety Reports (ICSRs) associated with an anti-TNF drug and related to the pregnant patients with psoriasis from 2009 and 2023, focusing our analysis on the specific pregnancy outcomes and fetal/neonatal disorders. The most common pregnancy-related adverse event was spontaneous abortion, predominantly related to adalimumab and certolizumab. Certolizumab was also reported in cases of caesarean section, gestational diabetes, abortion, fetal death, fetal distress syndrome, pre-eclampsia, and premature separation of placenta. Generally, the findings from our study depicted a safety profile that overlapped for each anti-TNF drug, both in maternal/neonatal outcomes and other adverse events, suggesting no substantial differences between treatments. We advocate for further investigations before making concrete recommendations.

A patient with axial spondylarthritis who experienced pancytopenia while receiving anti-TNF therapy.

Aplastic anemia is a rare and heterogeneous disease that causes pancytopenia and aplasia of the bone marrow. It is characterized by a failure of hematopoiesis. It is believed that approximately 65% of cases of acquired aplastic anemia are idiopathic. In a subset of cases, a drug or infection is the cause of bone marrow failure. This case report presents a 38-year-old patient with axial spondylarthritis who developed pancytopenia and was diagnosed with aplastic anemia during anti-TNF-α treatment.

Plasma Cytokines for the Prediction of the Effectiveness of TNFα Inhibitors Etanercept, Infliximab, and Adalimumab in the Treatment of Psoriasis.

Background/Objectives: Psoriasis is a chronic, inflammatory, immuno-mediated cutaneous disease characterized by a prominent TNFα-IL23/IL17 immune axis. In recent years, targeted therapies have become standard practice for managing moderate-to-severe psoriasis and have demonstrated efficacy. At the same time, identifying factors associated with the success or failure of TNFα inhibitor therapy remains one of the most difficult aspects in psoriasis treatment. Methods: A clinical, non-randomized study was conducted to evaluate the impact of TNFα inhibitors on the plasma cytokine profiles in patients with moderate-to-severe psoriasis vulgaris (ICD-10 code L40.0). The patients were treated with either etanercept, adalimumab, or infliximab for 16 weeks. Plasma cytokine profiles were assessed using a BioPlex200 System. Results: By the 16th week of therapy, a positive treatment response (PASI ≥ 75) was observed in 51 patients (63%), while 30 patients (37%) showed no response (PASI ≤ 50). When using etanercept, a positive effect was observed in 11 patients (41%), in 14 patients (52%) using adalimumab, and in 26 patients (96%) using infliximab. Analysis of the baseline cytokine levels revealed no differences between the "positive effect" and "no effect" groups, except for IL20, which was 2.61 times higher in the "positive effect" group compared to the "no effect" group, suggesting its potential predictive role in the effectiveness of therapy with TNFα inhibitors. Treatment led to a decrease in IL17F, IL31, sCD40L, and VEGF for all patients, and in IL20 for the "positive effect" group. The increase in ICAM1 in the "no effect" group suggests the possible retention of active migration and the fixation of T cells in the affected skin in these patients. No significant difference in cytokine levels was observed when categorizing patients into subgroups based on the effectiveness of therapy with etanercept, infliximab, and adalimumab; only a pre- and post-treatment difference in the whole cohort was noted. A random forest model showed the importance of VEGF, sCD40L, and ICAM1. Conclusions: The baseline levels of VEGF, sCD40L, and ICAM1, as well as IL20, could serve as potential predictors of treatment effectiveness using TNFa inhibitors. However, this hypothesis requires confirmation with a larger patient population.

TNF-alpha blockade in Primary Chronic Non-Bacterial Osteomyelitis of the Mandible.

OBJECTIVES: Primary chronic Non-Bacterial Osteomyelitis of the jaw is a rare auto-inflammatory disease of unknown aetiology that bears pathophysiological resemblance to both the synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome in adults and chronic recurrent multifocal osteomyelitis (CRMO) in children. Both SAPHO and CRMO respond to TNF-alpha blockade. Previously reported treatment regimens in CNOM including non-steroidal anti-inflammatory drugs, corticosteroids, antibiotics, anti-resorptive therapy, and surgery all bear disappointing results. TNF- α blockade is suggested as a treatment option by some experts but this is not backed by any clinical data.We sought to retrospectively and exhaustively report our experience of anti-TNF alpha therapy in refractory CNOM. METHODS: Fifteen patients with refractory CNOM and high disease burden were referred to our centre. TNF- α blockade was attempted in 10 cases, given its efficacy in neighbouring diseases, its good tolerance profile and failure of previous treatment strategiesWe herein retrospectively report detailed outcomes for all patients having received anti-TNF alpha therapy for this indication in our centre. RESULTS: TNF-α-targeting therapy resulted in a rapid and sustained remission in a majority of patients with CNOM, without serious adverse events. Treatment was tapered and stopped without relapse in some patients despite a refractory course of several years. Male sex seems to be associated with a poorer outcome. CONCLUSION: Our results suggest that blocking TNF-α is efficient and safe in CNOM.

Etanercept versus Methotrexate in the Treatment of Psoriasis and Associated Metabolic Syndrome: 12-Month Open-Label Comparative Study.

INTRODUCTION: Psoriasis is a chronic inflammatory systemic disease accompanied by systemic damage that leads to the development of multiple comorbidities including metabolic syndrome. Conventional systemic therapies for psoriasis are associated with toxicity and have a greater burden on the patients. The study aimed to assess the effectiveness of etanercept (ETN) monotherapy in comparison with methotrexate (MTX) monotherapy. METHODS: In this prospective interventional comparative open-label study, 117 patients with psoriasis were randomized to 2 groups; 1 group of 42 patients; 32 (67.2%) males and 10 (23.8%) females treated with MTX, and the second group of 75 patients; 54 (72%) males and 21 (28%) females treated with ETN. Full laboratory investigations, body mass index (BMI), measurement of skin disease severity which was performed using Psoriasis Area Severity Index (PASI), and the reduction of 75% of the skin lesions (PASI 75) were calculated for all participants. RESULTS: In the MTX group, there were no significant differences in BMI, or blood pressure after 12 weeks of the study. There is a reduction in the values of FBS, TSC, LDL, TRIG, ESR, CRP, and PASI, but this reduction was statistically not significant. Ten (23.8%) patients achieved PASI 75. In the ETN group, except for BMI, systolic and diastolic blood pressure, all other metabolic syndrome components, inflammatory markers, and PASI were decreased; the reduction was statistically significant. Sixty (80%) patients achieved PASI 75. CONCLUSION: Etanercept monotherapy showed greater efficacy than MTX monotherapy in the treatment of moderate to severe plaque-type psoriasis as it achieved greater reductions in PASI score and greater achievement of PASI 75 after 12 weeks. Etanercept monotherapy showed greater efficacy than MTX monotherapy in the improvement of all components of the associated metabolic syndrome except for BMI, which was increased in etanercept-treated patients.

Effects of Etanercept on Experimental Osteoarthritis in Rats: Role of Histone Deacetylases.

OBJECTIVE: Mounting evidence suggests that histone deacetylases (HDAC) inhibitors reduce cartilage destruction in animal models of osteoarthritis (OA). Tumor necrosis factor (TNF)-α-blocking treatment for OA may provide effective joint protection by slowing joint damage. To investigate the effects of intraperitoneal administration of etanercept (a TNF-α inhibitor) on OA development in rats and changes in the nociceptive behavior of rats and expression of HDACs, RUNX2, and MMP13 in cartilage. METHODS: Induction of OA in Wistar rats was accomplished through anterior cruciate ligament transection (ACLT). One or five milligrams (mg) of etanercept was administered intraperitoneally for 5 consecutive weeks after ACLT to the ACLT + etanercept (1 and 5 mg/kg) groups. Nociceptive behavior and changes in knee joint width were analyzed. Cartilage was evaluated histologically and immunohistochemically. RESULTS: ACLT + etanercept significantly improved mechanical allodynia and weight-bearing distribution compared to ACLT alone. In OA rats treated with etanercept, cartilage degeneration and synovitis were significantly less pronounced than those in ACLT rats. OA-affected cartilage also showed reduced expression of HDAC 6, 7, RUNX-2, and MMP-13 in response to etanercept but increased expression of HDAC4. CONCLUSION: Our study demonstrated that etanercept therapy (1) attenuated the development of OA and synovitis in rats, (2) reduced nociception, and (3) regulated chondrocyte metabolism, possibly by inhibiting cell HDAC6 and HDAC7, RUNX2, and MMP13 and increasing HDAC4 expression. Based on new evidence, etanercept may have therapeutic potential in OA.

TNF-Alpha Inhibitors Induced Eosinophilia: An Undervalued Side Effect of Such Biologicals.

INTRODUCTION: We present an unusual case of a 28-year-old rheumatologic male patient who developed eosinophilia while he was on etanercept therapy first and then on golimumab. CASE REPRESENTATION: Although eosinophilia is rarely reported in the literature as a side-effect of various Tumor Necrosis Factor-alpha [TNF-alpha] antagonists, it represents a riddle about the future treatments of these patients since the persistence of therapy might lead to the onset of dermatologic or visceral eosinophilic complications in such patients. CONCLUSION: Furthermore, the pathogenesis of eosinophilia is still unknown, and all the proposed hypotheses do not explain the eosinophilic proliferation in certain subjects.

Study on Cloning and Expression of TNF-α Variants in E. coli: Production, Purification, and Interaction with Anti-TNF-α Inhibitors.

BACKGROUND: TNF-α is a proinflammatory cytokine and plays a role in cell proliferation, differentiation, survival, and death pathways. When administered at high doses, it may cause damage to the tumor vasculature, thereby increasing the permeability of the blood vessels. Therefore, monitoring the dose and the response of the TNF-α molecule is essential for patients' health. OBJECTIVES: This study aimed to clone, express, and purify the active form of the TNF-α protein, which can interact with various anti-TNF-α inhibitors with high efficiency. METHODS: Recombinant DNA technology was used to clone three different versions of codon-optimized human TNF-α sequences to E. coli. Colony PCR protocol was used for verification and produced proteins were analyzed through SDS-PAGE and western blot. Size exclusion chromatography was used to purify sTNF-α. ELISA techniques were used to analyze and compare binding efficiency of sTNF-α against three different standards. RESULTS: Under native condition (25°C), interaction between sTNF-α and anti-TNF-α antibody was 3,970, compared to positive control. The interaction was 0,587, whereas it was 0,535 for TNF- α and anti-TNF-α antibodies under denaturing conditions (37°C). F7 of sTNF-α (920 µg/mL) had the same/higher binding efficiency to adalimumab, etanercept, and infliximab, compared to commercial TNF-α. CONCLUSION: This study was the first to analyze binding efficiency of homemade sTNF-α protein against three major TNF-α inhibitors (adalimumab, etanercept, and infliximab) in a single study. The high binding efficiency of sTNF-α with adalimumab, etanercept, and infliximab, evidenced in this study supports the feasibility of its use in therapeutic applications, contributing to more sustainable, cost-effective, and independent healthcare system.

Etanercept ameliorates chronic mild stress-induced depressive-like behavior in rats: Crosstalk between MAPK and STAT3 pathways and norepinephrine and serotonin transporters.

Depression is a serious medical illness characterized by persistent feelings of sadness, hopelessness, and lack of interest in daily activities. It can interfere with daily functioning and quality of life. Despite decades of research, the pathophysiology of depression remains incompletely understood. The correlation between depression and inflammation has recently attracted considerable attention. This study investigated the potential antidepressant effect of etanercept, a tumor necrosis factor-alpha (TNF-α) inhibitor, utilizing a chronic mild stress (CMS) model in rats. Male Wistar rats were divided into two groups; one following a non-stressed protocol and the other a stressed protocol for 5 weeks. From the beginning of the third week, rats were treated either with saline daily or with etanercept twice a week (0.3 mg/kg, i.p.) or with fluoxetine daily (10 mg/kg, i.p) as a reference. Etanercept exhibited comparable effects to those of fluoxetine in counteracting CMS-induced behavioral manifestation in the forced swimming and splash tests. Etanercept also restored serotonin and norepinephrine levels to control values in the prefrontal cortex (PFC). Moreover, the current study verified the antioxidant and anti-inflammatory effects of etanercept. Interestingly, etanercept halted the expression of both norepinephrine and serotonin transporters in stressed rats. This could be attributed to abrogation of the p38 mitogen-activated protein kinase (p38 MAPK) and signal transducer and activator of transcription 3 (STAT-3) pathways in the PFC. The findings of the present study contribute to the understanding of the potential of etanercept as an antidepressant and provide insights into the neurobiological mechanisms underlying its therapeutic effects.

Efficacy of switching from originator etanercept to biosimilar YLB113 in real-world patients with rheumatoid arthritis: A retrospective 12 months follow-up study.

Purpose: To investigate the disease activity in real-world patients with rheumatoid arthritis (RA) who switched from originator etanercept (ETN) to biosimilar YLB113. Methods: Forty one RA patients who switched from ETN to YLB113 were divided into 2 groups based on the Disease Activity Score based on the 28-joint count (DAS28) 12 months after switching (R group: DAS28 < 2.6, N group: DAS28 ≥ 2.6), and the baseline characteristics were statistically examined. A receiver operating characteristics (ROC) analysis was performed to estimate the cut-off value of DAS28 at baseline to achieve remission 12 months after switching. Results: There was no significant difference in the DAS28 at baseline and 12 months after switching (p = .83). Sixteen out of the 20 patients in remission at baseline achieved remission after switching. A univariate analysis revealed the rheumatoid factor (p = .04) and DAS28 (p < .001) at baseline were significantly lower in the R group than in the N group. Furthermore, logistic regression analysis revealed DAS28 was an independent factor (p = .004) for achieving remission 12 months after switching. An ROC curve analysis showed the optimal cut-off value for DAS28 at baseline to achieve remission at 12 months after switching was 2.5. Conclusions: RA patients who achieved remission using originator ETN, were able to maintain remission even if they switched to YLB113.

Efficacy and safety of tumor necrosis factor inhibitors for systemic juvenile idiopathic arthritis: a systematic review.

OBJECTIVES: This systematic review assessed the efficacy and safety of tumor necrosis factor (TNF) inhibitors in patients with systemic juvenile idiopathic arthritis (JIA). METHODS: Studies were searched using PubMed, Embase, Cochrane, Ichushi-Web, and clinical trial registries (from 2000 to 2021). The risk of bias was assessed using the Cochrane Risk of Bias version 2 for randomized controlled trials (RCTs) and the manual for development clinical practice guidelines by Minds, a project promoting evidence-based medicine in Japan, for observational studies. RESULTS: One RCT and 22 observational studies were included. In the RCT on infliximab, the American College of Rheumatology pediatric (ACR Pedi) 30/50/70 responses at 14 weeks were 63.8%/50.0%/22.4%, with relative risks of 1.30 (95% confidence interval [CI]: 0.94-1.79)/1.48 (95% CI: 0.95-2.29)/1.89 (95% CI: 0.81-4.40), respectively. In the observational studies, ACR Pedi 30/50/70 responses for etanercept at 12 months were 76.7%/64.7%/46.4%, respectively. Infliximab treatment caused anaphylaxis in 17% and an infusion reaction in 23% of patients. The incidence of macrophage activation syndrome, serious infection and malignancy caused by TNF inhibitors was 0%-4%. CONCLUSIONS: Thus, although TNF inhibitors were relatively safe, they were unlikely to be preferentially administered in patients with systemic JIA because of their inadequate efficacy. Further studies, particularly well-designed RCTs, are necessary to confirm the efficacy and safety of TNF inhibitors for systemic JIA.

Increasing the etanercept dose in a treat-to-target approach in juvenile idiopathic arthritis: does it help to reach the target? A post-hoc analysis of the BeSt for Kids randomised clinical trial.

BACKGROUND: Etanercept has been studied in doses up to 0.8 mg/kg/week (max 50 mg/week) in juvenile idiopathic arthritis (JIA) patients. In clinical practice higher doses are used off-label, but evidence regarding the relation with outcomes is lacking. We describe the clinical course of JIA-patients receiving high-dose etanercept (1.6 mg/kg/week; max 50 mg/week) in the BeSt for Kids trial. METHODS: 92 patients with oligoarticular JIA, RF-negative polyarticular JIA or juvenile psoriatic arthritis were randomised across three treat-to-target arms: (1) sequential DMARD-monotherapy (sulfasalazine or methotrexate (MTX)), (2) combination-therapy MTX + 6 weeks prednisolone and (3) combination therapy MTX + etanercept. In any treatment-arm, patients could eventually escalate to high-dose etanercept alongside MTX 10mg/m2/week. RESULTS: 32 patients received high-dose etanercept (69% female, median age 6 years (IQR 4-10), median 10 months (7-16) from baseline). Median follow-up was 24.6 months. Most clinical parameters improved within 3 months after dose-increase: median JADAS10 from 7.2 to 2.8 (p = 0.008), VAS-physician from 12 to 4 (p = 0.022), VAS-patient/parent from 38.5 to 13 (p = 0.003), number of active joints from 2 to 0.5 (p = 0.12) and VAS-pain from 35.5 to 15 (p = 0.030). Functional impairments (CHAQ-score) improved more gradually and ESR remained stable. A comparable pattern was observed in 11 patients (73% girls, median age 8 (IQR 6-9)) who did not receive high-dose etanercept despite eligibility (comparison group). In both groups, 56% reached inactive disease at 6 months. No severe adverse events (SAEs) occurred after etanercept dose-increase. In the comparison group, 2 SAEs consisting of hospital admission occurred. Rates of non-severe AEs per subsequent patient year follow-up were 2.27 in the high-dose and 1.43 in the comparison group. CONCLUSIONS: Escalation to high-dose etanercept in JIA-patients who were treated to target was generally followed by meaningful clinical improvement. However, similar improvements were observed in a smaller comparison group who did not escalate to high-dose etanercept. No SAEs were seen after escalation to high-dose etanercept. The division into the high-dose and comparison groups was not randomised, which is a potential source of bias. We advocate larger, randomised studies of high versus regular dose etanercept to provide high level evidence on efficacy and safety. TRIAL REGISTRATION: Dutch Trial Register; NTR1574; 3 December 2008; https://onderzoekmetmensen.nl/en/trial/26585 .