Joost F. Swart

Factors Associated With Treatment Response to Etanercept in Juvenile Idiopathic Arthritis

CONTEXT Since the introduction of biologic therapies, the pharmacological treatment approach for juvenile idiopathic arthritis (JIA) has changed substantially, with achievement of inactive disease as a realistic goal. OBJECTIVE To determine the response to therapy after initiation of etanercept therapy among patients with JIA and to examine the association between baseline factors and response to etanercept treatment. DESIGN, SETTING, AND PATIENTS The Arthritis and Biologicals in Children Register, an ongoing prospective observational study since 1999, includes all Dutch JIA patients who used biologic agents. All biologically naive patients who started etanercept before October 2009 were included, with follow-up data to January 2011. Among the 262 patients, 185 (71%) were female, 46 (18%) had systemic-onset, and the median age at initiation of etanercept treatment was 12.4 years. MAIN OUTCOME MEASURES Excellent response (inactive disease or discontinuation earlier due to disease remission), intermediate response (more than 50% improvement from baseline, but no inactive disease), and poor response (less than 50% improvement from baseline or discontinuation earlier due to ineffectiveness or intolerance) evaluated 15 months after initiation of etanercept. RESULTS At 15 months after treatment initiation, 85 patients (32%) were considered excellent responders; 92 (36%), intermediate responders; and 85 (32%), poor responders. Compared with an intermediate or poor response, an excellent response was associated with lower baseline disability score (range, 0-3 points, with 0 being the best score; adjusted odds ratio [OR] per point increase, 0.49; 95% CI, 0.33-0.74); fewer disease-modifying antirheumatic drugs (DMARD) (including methotrexate) used before initiating etanercept (adjusted OR per DMARD used, 0.64; 95% CI, 0.43-0.95), and younger age at onset (adjusted OR per year increase, 0.92; 95% CI, 0.84-0.99). Compared with an intermediate or excellent response, a poor response was associated with systemic JIA (adjusted OR systemic vs nonsystemic categories, 2.92; 95% CI, 1.26-6.80), and female sex (adjusted OR female vs male, 2.16; 95% CI, 1.12-4.18). Within the first 15 months of etanercept treatment, 119 patients experienced 1 or more infectious, noninfectious, or serious adverse events, including 37 among those with an excellent response, 36 with an intermediate response, and 46 with a poor response. Within the first 15 months of treatment, 61 patients discontinued etanercept treatment, including 4 with an excellent response, 0 with an intermediate response, and 57 with a poor response. In a secondary analysis of 262 patients with a median follow-up of 35.6 months after initiation of etanercept, a range of 37% to 49% of patients reached inactive disease. The mean adherence to etanercept was 49.2 months (95% CI, 46.4-52.0) for patients with an excellent response after 15 months, 47.5 months (95% CI, 44.9-50.1) for patients with an intermediate response, and 17.4 months (95% CI, 13.6-21.2) for patients with a poor response. CONCLUSIONS Among patients with JIA who initiated treatment with etanercept, one-third achieved an excellent response, one-third an intermediate response, and one-third a poor response to therapy. Achievement of an excellent response was associated with low baseline disability scores, DMARDs used before initiating etanercept, and younger age at onset of JIA. Achievement of a poor treatment response was associated with systemic JIA and female sex.

Tumor necrosis factor-blocking agents for children with enthesitis-related arthritis--data from the dutch arthritis and biologicals in children register, 1999-2010

Objective. To evaluate the effectiveness and safety of biological agents in children with enthesitis-related arthritis (ERA). Methods. All patients with ERA in whom a biological agent was initiated between 1999 and 2010 were selected from the Dutch Arthritis and Biologicals in Children (ABC) register. In this ongoing multicenter observational register, data on the course of the disease and medication use are retrieved prospectively at the start of the biological agent, after 3 months, and yearly thereafter. Inactive disease was assessed in accordance with the Wallace criteria. Results. Twenty-two patients with ERA started taking 1 or more biological agents: 20 took etanercept, 2 took adalimumab (1 switched from etanercept to adalimumab), and 2 took infliximab (1 switched from etanercept to infliximab). Characteristics: 77% were male, 77% had enthesitis, 68% were HLA-B27-positive. The median age of onset was 10.4 (IQR 9.4–12.0) years; median followup from the start of the biological agent was 1.2 (IQR 0.5–2.4) years. Intention-to-treat analysis shows that inactive disease was achieved in 7 of 22 patients (32%) after 3 months, 5 of 13 patients (38%) after 15 months, and 5 of 8 patients (63%) after 27 months of treatment. Two patients discontinued etanercept because of ineffectiveness, and switched to adalimumab (inactive disease achieved) or infliximab (decline in joints with arthritis after 3 months of treatment). One patient discontinued etanercept because of remission, but had flare and restarted treatment, with good clinical response. No serious adverse events occurred. Conclusion. Tumor necrosis factor (TNF)-blocking agents seem effective and safe for patients with ERA that was previously unresponsive to 1 or more DMARD. However, a sustained disease-free state could not be achieved, and none discontinued TNF-blocking agents successfully.

Effects of the Live Attenuated Measles-Mumps-Rubella Booster Vaccination on Disease Activity in Patients With Juvenile Idiopathic Arthritis: A Randomized Trial

IMPORTANCE The immunogenicity and the effects of live attenuated measles-mumps-rubella (MMR) vaccination on disease activity in patients with juvenile idiopathic arthritis (JIA) are matters of concern, especially in patients treated with immunocompromising therapies. OBJECTIVES To assess whether MMR booster vaccination affects disease activity and to describe MMR booster immunogenicity in patients with JIA. DESIGN, SETTING, AND PARTICIPANTS Randomized, multicenter, open-label clinical equivalence trial including 137 patients with JIA aged 4 to 9 years who were recruited from 5 academic hospitals in The Netherlands between May 2008 and July 2011. INTERVENTION Patients were randomly assigned to receive MMR booster vaccination (n=68) or no vaccination (control group; n=69). Among patients taking biologics, these treatments were discontinued at 5 times their half-lives prior to vaccination. MAIN OUTCOMES AND MEASURES Disease activity as measured by the Juvenile Arthritis Disease Activity Score (JADAS-27), ranging from 0 (no activity) to 57 (high activity). Disease activity in the year following randomization was compared between revaccinated patients and controls using a linear mixed model. A difference in JADAS-27 of 2.0 was the equivalence margin. Primary immunogenicity outcomes were seroprotection rates and MMR-specific antibody concentrations at 3 and 12 months. RESULTS Of 137 randomized patients, 131 were analyzed in the modified intention-to-treat analysis, including 60 using methotrexate and 15 using biologics. Disease activity during complete follow-up did not differ between 63 revaccinated patients (JADAS-27, 2.8; 95% CI, 2.1-3.5) and 68 controls (JADAS-27, 2.4; 95% CI, 1.7-3.1), with a difference of 0.4 (95% CI, -0.5 to 1.2), within the equivalence margin of 2.0. At 12 months, seroprotection rates were higher in revaccinated patients vs controls (measles, 100% vs 92% [95% CI, 84%-99%]; mumps, 97% [95% CI, 95%-100%] vs 81% [95% CI, 72%-93%]; and rubella, 100% vs 94% [95% CI, 86%-100%], respectively), as were antibody concentrations against measles (1.63 vs 0.78 IU/mL; P = .03), mumps (168 vs 104 RU/mL; P = .03), and rubella (69 vs 45 IU/mL; P = .01). Methotrexate and biologics did not affect humoral responses, but low patient numbers precluded definite conclusions. CONCLUSION AND RELEVANCE Among children with JIA who had undergone primary immunization, MMR booster vaccination compared with no booster did not result in worse JIA disease activity and was immunogenic. Larger studies are needed to assess MMR effects in patients using biologic agents. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00731965.

Effects of the Live Attenuated Measles-Mumps-Rubella Booster Vaccination on Disease Activity in Patients With Juvenile Idiopathic Arthritis

IMPORTANCE The immunogenicity and the effects of live attenuated measles-mumps-rubella (MMR) vaccination on disease activity in patients with juvenile idiopathic arthritis (JIA) are matters of concern, especially in patients treated with immunocompromising therapies. OBJECTIVES To assess whether MMR booster vaccination affects disease activity and to describe MMR booster immunogenicity in patients with JIA. DESIGN, SETTING, AND PARTICIPANTS Randomized, multicenter, open-label clinical equivalence trial including 137 patients with JIA aged 4 to 9 years who were recruited from 5 academic hospitals in The Netherlands between May 2008 and July 2011. INTERVENTION Patients were randomly assigned to receive MMR booster vaccination (n=68) or no vaccination (control group; n=69). Among patients taking biologics, these treatments were discontinued at 5 times their half-lives prior to vaccination. MAIN OUTCOMES AND MEASURES Disease activity as measured by the Juvenile Arthritis Disease Activity Score (JADAS-27), ranging from 0 (no activity) to 57 (high activity). Disease activity in the year following randomization was compared between revaccinated patients and controls using a linear mixed model. A difference in JADAS-27 of 2.0 was the equivalence margin. Primary immunogenicity outcomes were seroprotection rates and MMR-specific antibody concentrations at 3 and 12 months. RESULTS Of 137 randomized patients, 131 were analyzed in the modified intention-to-treat analysis, including 60 using methotrexate and 15 using biologics. Disease activity during complete follow-up did not differ between 63 revaccinated patients (JADAS-27, 2.8; 95% CI, 2.1-3.5) and 68 controls (JADAS-27, 2.4; 95% CI, 1.7-3.1), with a difference of 0.4 (95% CI, -0.5 to 1.2), within the equivalence margin of 2.0. At 12 months, seroprotection rates were higher in revaccinated patients vs controls (measles, 100% vs 92% [95% CI, 84%-99%]; mumps, 97% [95% CI, 95%-100%] vs 81% [95% CI, 72%-93%]; and rubella, 100% vs 94% [95% CI, 86%-100%], respectively), as were antibody concentrations against measles (1.63 vs 0.78 IU/mL; P = .03), mumps (168 vs 104 RU/mL; P = .03), and rubella (69 vs 45 IU/mL; P = .01). Methotrexate and biologics did not affect humoral responses, but low patient numbers precluded definite conclusions. CONCLUSION AND RELEVANCE Among children with JIA who had undergone primary immunization, MMR booster vaccination compared with no booster did not result in worse JIA disease activity and was immunogenic. Larger studies are needed to assess MMR effects in patients using biologic agents. TRIAL REGISTRATION clinicaltrials.gov Identifier: NCT00731965.

Haematopoietic stem cell transplantation for autoimmune diseases

Autologous haematopoietic stem cell transplantation (HSCT) is the only treatment that is able to induce long-term, drug-free and symptom-free remission in several refractory autoimmune rheumatic diseases. Over 3,000 HSCT procedures for rheumatic and nonrheumatic severe autoimmune diseases have been performed worldwide. Specific conditioning regimens are currently used to eradicate the autoreactive immunological memory of patients. Although in vivo immune cell depletion with antithymocyte globulin or anti-CD52 is the norm for many regimens, ex vivo selection of CD34+ stem cells from the graft is controversial. Following the extensive immune depletion associated with serotherapy and chemotherapy, HSCT effectively resets the immune system by renewing the CD4+ T cell compartment, especially the regulatory T cell population. The risk of transplant-related mortality (TRM) within the first 100 days should be weighed against the risk of disease-related mortality, and the careful selection and screening of patients before transplantation is essential. Systemic sclerosis is the first autoimmune disease for which HSCT has been shown, in a randomized, controlled trial, to be associated with increased TRM in the first year but a significant long-term, event-free survival benefit afterwards. In this Review, we discuss the immunological mechanisms of HSCT in various autoimmune diseases and current HSCT regimens. After carefully taking into consideration the risks and benefits of HSCT and alternative therapies, we also discuss the efficacy, complications and proposed indications of this procedure.

Trends in prescription of biological agents and outcomes of juvenile idiopathic arthritis: results of the Dutch national Arthritis and Biologics in Children Register

Background Treatment of juvenile idiopathic arthritis (JIA) has changed dramatically since the introduction of biological agents in 1999. Objective To evaluate trends in prescription patterns of biological agents and the subsequent outcome of JIA. Methods The Arthritis and Biologics in Children register (multicentre prospective observational study) aimed to include all consecutive patients with JIA in the Netherlands who had started biological agents since 1999. Patients were divided according to year of introduction of first biological agent. Patient characteristics at introduction of the first biological agent and its effectiveness were analysed over 12 years. Results 335 patients with non-systemic JIA and 86 patients with systemic JIA started a biological agent between 1999 and 2010. Etanercept remained the most often prescribed biological agent for non-systemic JIA; anakinra became first choice for systemic JIA. The use of systemic glucocorticoids and synthetic disease-modifying antirheumatic drugs before biological agents decreased. During these 12 years of observation, biological agents were prescribed earlier in the disease course and to patients with lower baseline JADAS (Juvenile Arthritis Disease Activity Score) disease activity. All baseline disease activity parameters were lowered in patients with non-systemic JIA. In systemic JIA, prescription patterns changed towards very early introduction of biological agents (median 0.4 years of disease duration) in patients with a low number of joints with active arthritis and high erythrocyte sedimentation rates. These changes for both systemic and non-systemic JIA resulted in more patients with inactive disease after 3 and 15 months of treatment. Conclusions Biological agents are increasingly prescribed, earlier in the disease and in patients with JIA with lower disease activity. These changes are accompanied by better short-term disease outcomes.

Effectiveness and safety of a second and third biological agent after failing etanercept in juvenile idiopathic arthritis: results from the Dutch National ABC Register

Objective To evaluate the effectiveness and safety of switching to a second or third biological agent in juvenile idiopathic arthritis (JIA) after etanercept failure. Methods The Arthritis and Biologicals in Children Register aims to include all Dutch JIA patients who have used biological agents. Data on the disease course were used to estimate drug survival with Kaplan–Meier and calculate adverse event (AE) rates. Results Of 307 biologically naive JIA patients who started etanercept, 80 (26%) switched to a second and 22 (7%) to a third biological agent. During 1030 patient-years of follow-up after the introduction of etanercept, 49 switches to adalimumab, 28 infliximab, 17 anakinra, four abatacept and four trial drugs were evaluated. 84% (95% CI 80% to 88%) of patients who started etanercept as a first biological agent were, after 12 months, still on the drug, compared with 47% (95% CI 35% to 60%) who started a second and 51% (95% CI 26% to 76%) who started a third biological agent. Patients who switched because of primary ineffectiveness continued the second agent less often (32%, 95% CI 12% to 53%). After etanercept failure, drug continuation of adalimumab was similar to infliximab for patients with non-systemic JIA; anakinra was superior to a second TNF-blocker for systemic JIA. AE rates within first 12 months after initiation were comparable for each course and each biological agent. Conclusions Switching to another biological agent is common, especially for systemic JIA patients. A second (and third) agent was less effective than the first. The choice of second biological agent by the physician mainly depends on availability and JIA category.

What are the immunological consequences of long-term use of biological therapies for juvenile idiopathic arthritis?

This review summarizes the immunological consequences of biological therapies used in juvenile idiopathic arthritis (JIA). For every frequently used biological agent the characteristics are clearly specified (molecular target, isotype, registered indication for JIA, route of administration, half-life, contraindication, very common side effects, expected time of response and average cost in the first year). The emphasis of this review is on the immunological side effects that have been encountered for every separate agent in JIA populations. For each agent these adverse events have been calculated as incidence per 100 patient-years for the following categories: serious infections, tuberculosis, malignancies, response to vaccination, new-onset autoimmune diseases and development of anti-drug antibodies. There are large differences in side effects between various agents and there is a clear need for an international and standardized collection of post-marketing surveillance data of biologicals in the vulnerable group of JIA patients. Such an international pharmacovigilance database, called Pharmachild, has now been started.

Treatment choices of paediatric rheumatologists for juvenile idiopathic arthritis: etanercept or adalimumab?

OBJECTIVES To evaluate differences in baseline characteristics between etanercept- and adalimumab-treated JIA patients and to reveal factors that influence the choice between these TNF inhibitors, which are considered equally effective in the recent ACR recommendations for JIA treatment. METHODS Biologic-naïve JIA patients with active arthritis who started treatment with adalimumab or etanercept between March 2008 and December 2011 were selected from the Dutch Arthritis and Biologicals in Children register. Baseline characteristics were compared. Focus group interviews with paediatric rheumatologists were performed to evaluate factors determining treatment choices. RESULTS A total of 193 patients started treatment with etanercept and 21 with adalimumab. Adalimumab-treated patients had longer disease duration prior to the start of biologics (median 5.7 vs 2.0 years) and more often a history of uveitis (71% vs 4%). Etanercept-treated patients had more disability at baseline (median Childhood Health Assessment Questionnaire score 1.1 vs 0.4) and more active arthritis (median number of active joints 6 vs 4). The presence of uveitis was the most important factor directing the choice towards adalimumab. Factors specific for the paediatric population-such as painful adalimumab injections-as well as the physicians familiarity with the drug accounted for the preference for etanercept. CONCLUSION Although the two TNF inhibitors are considered equally effective, in daily practice etanercept is most often prescribed; adalimumab is mainly preferred when uveitis is present. In choosing the most suitable biologic treatment, paediatric rheumatologists take into account drug and patient factors, considering newly published data and cautiously implementing this into daily care.

Mesenchymal stem cell therapy in proteoglycan induced arthritis

Objectives To explore the immunosuppressive effect and mechanism of action of intraperitoneal (ip) and intra-articular (ia) mesenchymal stem cell (MSC) injection in proteoglycan induced arthritis (PGIA). Methods MSC were administered ip or ia after establishment of arthritis. We used serial bioluminescence imaging (BLI) to trace luciferase-transfected MSC. Mice were sacrificed at different time points to examine immunomodulatory changes in blood and secondary lymphoid organs. Results Both ip and local ia MSC injection resulted in a beneficial clinical and histological effect on established PGIA. BLI showed that MSC ip and ia in arthritic mice are largely retained for several weeks in the peritoneal cavity or injected joint respectively, without signs of migration. Following MSC treatment pathogenic PG-specific IgG2a antibodies in serum decreased. The Th2 cytokine IL-4 was only upregulated in PG-stimulated lymphocytes from spleens in ip treated mice and in lymphocytes from draining lymph nodes in ia treated mice. An increase in production of IL-10 was seen with equal distribution. Although IFN-γ was also elevated, the IFN-γ/IL-4 ratio in MSC treated mice was opposite to the ratio in (untreated) active PGIA. Conclusions MSC treatment, both ip and ia, suppresses PGIA, a non-collagen induced arthritis model. MSC are largely retained for weeks in the injection region. MSC treatment induced at the region of injection a deviation of PG-specific immune responses, suggesting a more regulatory phenotype with production of IL-4 and IL-10, but also of IFN-γ, and a systemic decrease of pathogenic PG-specific IgG2a antibodies. These findings underpin the potential of MSC treatment in resistant arthritis.