Incidence and risk factors for adalimumab and infliximab anti-drug antibodies in rheumatoid arthritis: A European retrospective multicohort analysis.

OBJECTIVES: To evaluate the incidence of anti-drug antibody (ADA) occurrences and ADA-related risk factors under adalimumab and infliximab treatment in rheumatoid arthritis (RA) patients. METHODS: The study combined retrospective cohorts from the ABIRISK project totaling 366 RA patients treated with adalimumab (n = 240) or infliximab (n = 126), 92.4% of them anti-TNF naive (n = 328/355) and 96.6% of them co-treated with methotrexate (n = 341/353) with up to 18 months follow-up. ADA positivity was measured by enzyme-linked immunosorbent assay. The cumulative incidence of ADA was estimated, and potential bio-clinical factors were investigated using a Cox regression model on interval-censored data. RESULTS: ADAs were detected within 18 months in 19.2% (n = 46) of the adalimumab-treated patients and 29.4% (n = 37) of the infliximab-treated patients. The cumulative incidence of ADA increased over time. In the adalimumab and infliximab groups, respectively, the incidence was 15.4% (5.2-20.2) and 0% (0-5.9) at 3 months, 17.6% (11.4-26.4) and 0% (0-25.9) at 6 months, 17.7% (12.6-37.5) and 34.1% (11.4-46.3) at 12 months, 50.0% (25.9-87.5) and 37.5% (25.9-77.4) at 15 months and 50.0% (25.9-87.5) and 66.7% (37.7-100) at 18 months. Factors associated with a higher risk of ADA development were: longer disease duration (1-3 vs. < 1 year; adalimumab: HR 3.0, 95% CI 1.0-8.7; infliximab: HR 2.7, 95% CI 1.1-6.8), moderate disease activity (DAS28 3.2-5.1 vs. < 3.2; adalimumab: HR 6.6, 95% CI 1.3-33.7) and lifetime smoking (infliximab: HR 2.7, 95% CI 1.2-6.3). CONCLUSIONS: The current study focusing on patients co-treated with methotrexate for more than 95% of them found a late occurrence of ADAs not previously observed, whereby the risk continued to increase over 18 months. Disease duration, DAS28 and lifetime smoking are clinical predictors of ADA development.

MRP8/14 serum levels as a strong predictor of response to biological treatments in patients with rheumatoid arthritis.

BACKGROUND: One-third of rheumatoid arthritis (RA) patients treated with biological therapy show lack of response. The use of predictive biomarkers to identify responders to treatment may provide guidance in optimising treatment strategies and reduce unnecessary side effects and costs. OBJECTIVE: To test the ability of myeloid-related proteins (MRP)8/14 protein complexes, an endogenous TLR-4 receptor agonist, to predict and monitor response to biologics in RA patients. METHODS: 170 RA patients treated with adalimumab (n=86), infliximab (n=60) or rituximab (n=24) were categorised into clinical responders (n=123) and non-responders (n=47). MRP8/14 serum complexes were measured at baseline, and 4 and 16 weeks after initiation of treatment and related to response outcome. RESULTS: Before initiation of treatment, responders showed significantly higher MRP8/14 protein complex levels compared with non-responders in each prospective cohort (p=0.010, p=0.001 and p<0.001, respectively). Logistic regression analysis showed that having high MRP8/14 baseline levels increased the odds of being a responder by 3.3 up to 55. In responders to adalimumab or infliximab treatment, MRP8/14 levels decreased after 4 weeks of treatment by 46% and 60% and after 16 weeks by 61% and 68%, respectively. In contrast, MRP8/14 levels were stable in non-responders. In patients treated with rituximab, MRP8/14 levels decreased by 59% after 16 weeks in responders and increased by 89% after 16 weeks in non-responders. CONCLUSION: Serum concentrations of MRP8/14 protein complex are a promising biomarker to predict response to biological therapy in active RA patients at baseline and could be used to monitor response to treatment across different mechanisms of action.

Genome-wide association study and gene expression analysis identifies CD84 as a predictor of response to etanercept therapy in rheumatoid arthritis.

Anti-tumor necrosis factor alpha (anti-TNF) biologic therapy is a widely used treatment for rheumatoid arthritis (RA). It is unknown why some RA patients fail to respond adequately to anti-TNF therapy, which limits the development of clinical biomarkers to predict response or new drugs to target refractory cases. To understand the biological basis of response to anti-TNF therapy, we conducted a genome-wide association study (GWAS) meta-analysis of more than 2 million common variants in 2,706 RA patients from 13 different collections. Patients were treated with one of three anti-TNF medications: etanercept (n = 733), infliximab (n = 894), or adalimumab (n = 1,071). We identified a SNP (rs6427528) at the 1q23 locus that was associated with change in disease activity score (ΔDAS) in the etanercept subset of patients (P = 8 × 10(-8)), but not in the infliximab or adalimumab subsets (P>0.05). The SNP is predicted to disrupt transcription factor binding site motifs in the 3' UTR of an immune-related gene, CD84, and the allele associated with better response to etanercept was associated with higher CD84 gene expression in peripheral blood mononuclear cells (P = 1 × 10(-11) in 228 non-RA patients and P = 0.004 in 132 RA patients). Consistent with the genetic findings, higher CD84 gene expression correlated with lower cross-sectional DAS (P = 0.02, n = 210) and showed a non-significant trend for better ΔDAS in a subset of RA patients with gene expression data (n = 31, etanercept-treated). A small, multi-ethnic replication showed a non-significant trend towards an association among etanercept-treated RA patients of Portuguese ancestry (n = 139, P = 0.4), but no association among patients of Japanese ancestry (n = 151, P = 0.8). Our study demonstrates that an allele associated with response to etanercept therapy is also associated with CD84 gene expression, and further that CD84 expression correlates with disease activity. These findings support a model in which CD84 genotypes and/or expression may serve as a useful biomarker for response to etanercept treatment in RA patients of European ancestry.

Anti-TNF therapy reduces serum levels of chemerin in rheumatoid arthritis: a new mechanism by which anti-TNF might reduce inflammation.

BACKGROUND: Chemerin is a specific chemoattractant for macrophages and dendritic cells (DC). In addition, it can rapidly stimulate macrophage adhesion to extracellular matrix proteins and adhesion molecules and is able to activate fibroblast-like synoviocytes (FLS), suggesting a role in the pathogenesis of rheumatoid arthritis (RA). Chemerin is also an adipocytokine that has been related to the inflammatory state of endothelial cells and as such could be involved in the changes in endothelial cells in RA and perhaps increased cardiovascular morbidity. We investigated whether anti-Tumor Necrosis Factor (TNF) treatment affects chemerin levels. MATERIALS AND METHODS: 49 patients with active RA (disease activity score evaluated in 28 joints (DAS28) ≥3.2) were started on adalimumab therapy. Blood was drawn from patients while fasting at baseline and 16 weeks after initiation of treatment. Chemerin serum levels were measured by ELISA and related to disease activity, mediators of inflammation and known risk factors for cardiovascular disease. RESULTS: Adalimumab therapy reduced chemerin serum levels, which was correlated with the reduction in DAS28 (r = 0.37, p = 0.009). In addition, the decrease in chemerin serum levels after anti-TNF treatment was associated with the decrease in serum levels of IL-6 (r = 0.39, p = 0.033) and macrophage migration inhibitory factor (MIF) (r = 0.31, p = 0.049). Baseline chemerin serum levels were not related to traditional risk factors for atherosclerosis, except perhaps for smoking (p = 0.07). CONCLUSIONS: This exploratory study shows that adalimumab therapy lowers chemerin levels, which is associated with the reduction in disease activity parameters, and inflammatory mediators IL-6 and MIF. This suggests a possible involvement of chemerin in the migration/retention of macrophages in the synovium. TRIAL REGISTRATION NEDERLANDS TRIAL REGISTER: NTR 857.

Experiences and needs for work participation in employees with rheumatoid arthritis treated with anti-tumour necrosis factor therapy.

PURPOSE: To investigate the experiences and needs with respect to work participation of employees with rheumatoid arthritis (RA) treated with anti-tumour necrosis factor (TNF) therapy. METHOD: Face-to-face interviews in 14 employees with RA on anti-TNF therapy focused on experiences, offered support and needs with respect to work participation. RESULTS: Experiences regarding work participation varied and ranged from fatigue at work, having no job control, not being understood by the work environment or difficulty dealing with emotions as a result of interaction within the work environment. Support by health care professionals for work participation was considered important, especially concerning social or psychological issues. Advice in becoming aware of one's changes in abilities was highly appreciated, as was the availability of professional advice in times of an urgent work issue due to RA. Employees mentioned an increase in social support at work and job control as important facilitating factors for work participation. CONCLUSION: Although patients with RA report improvement in their work functioning after starting anti-TNF therapy, employees continue facing challenges in working life due to RA. For support concerning work participation, it is recommended that health care professionals are more aware of work-related problems in patients with RA treated with anti-TNF therapy.

Improvement of work ability, quality of life, and fatigue in patients with rheumatoid arthritis treated with adalimumab.

OBJECTIVE: To assess the effect of 12-month treatment with adalimumab on work ability, quality of life, and fatigue in patients with active rheumatoid arthritis (RA). METHODS: One hundred twenty-six patients with active RA started treatment with adalimumab. Primary outcome measurements were work ability, assessed by the first item of the Work Ability Index, quality of life, assessed by the Rheumatoid Arthritis Quality of Life (RAQoL) instrument, and fatigue, assessed by the Checklist Individual Strength and the Need for Recovery after work Scale. RESULTS: All primary outcome measurements showed a significant improvement. The largest improvement for all outcome measurements was gained in the first 6 months of treatment and was sustained over the following 6 months. CONCLUSION: Adalimumab improves patient reported outcomes in addition to improving disease activity in established RA.

Rheumatoid arthritis risk allele PTPRC is also associated with response to anti-tumor necrosis factor alpha therapy.

OBJECTIVE: Anti-tumor necrosis factor alpha (anti-TNF) therapy is a mainstay of treatment in rheumatoid arthritis (RA). The aim of the present study was to test established RA genetic risk factors to determine whether the same alleles also influence the response to anti-TNF therapy. METHODS: A total of 1,283 RA patients receiving etanercept, infliximab, or adalimumab therapy were studied from among an international collaborative consortium of 9 different RA cohorts. The primary end point compared RA patients with a good treatment response according to the European League Against Rheumatism (EULAR) response criteria (n = 505) with RA patients considered to be nonresponders (n = 316). The secondary end point was the change from baseline in the level of disease activity according to the Disease Activity Score in 28 joints (triangle upDAS28). Clinical factors such as age, sex, and concomitant medications were tested as possible correlates of treatment response. Thirty-one single-nucleotide polymorphisms (SNPs) associated with the risk of RA were genotyped and tested for any association with treatment response, using univariate and multivariate logistic regression models. RESULTS: Of the 31 RA-associated risk alleles, a SNP at the PTPRC (also known as CD45) gene locus (rs10919563) was associated with the primary end point, a EULAR good response versus no response (odds ratio [OR] 0.55, P = 0.0001 in the multivariate model). Similar results were obtained using the secondary end point, the triangle upDAS28 (P = 0.0002). There was suggestive evidence of a stronger association in autoantibody-positive patients with RA (OR 0.55, 95% confidence interval [95% CI] 0.39-0.76) as compared with autoantibody-negative patients (OR 0.90, 95% CI 0.41-1.99). CONCLUSION: Statistically significant associations were observed between the response to anti-TNF therapy and an RA risk allele at the PTPRC gene locus. Additional studies will be required to replicate this finding in additional patient collections.