IL-6 pathway-driven investigation of response to IL-6 receptor inhibition in rheumatoid arthritis

Serum GM-CSF level is a predictor of treatment response to tocilizumab in rheumatoid arthritis patients: a prospective observational cohort study

BACKGROUND

The aim of this prospective observational cohort study was to unveil the predictors of treatment response to tocilizumab (TCZ) therapy in rheumatoid arthritis (RA) patients, in terms of clinical characteristics and serum proinflammatory cytokines, especially to explore the predictive value of granulocyte macrophage-colony stimulating factor (GM-CSF).

METHODS

Active adult RA patients with inadequate response to MTX intending to receive TCZ therapy were recruited prospectively in the study. A total of 174 severe RA patients were included for the identification of the associations between treatment response and the following characteristic features: demographics, medications, disease activity, serum proinflammatory cytokines and so on.

RESULTS

Disease duration (OR = 0.996), tender joint count (TJC)/68 (OR = 0.943), neutrophil ratio (W4/baseline) (OR = 0.224), the high level of GM-CSF > 5 ng/ml (OR = 0.414) at baseline were the independent adverse predictors of good response assessed by clinical disease activity index (CDAI) at week 24 (W24) for TCZ therapy in RA patients. Moreover, DAS28-ESR (OR = 2.951, P = 0.002) and the high level of GM-CSF > 10 ng/ml at baseline (OR = 5.419, P = 0.002) were independent predictors of poor response, but not the high level of GM-CSF > 5 ng/ml (OR = 2.713, P = 0.054). The patients in the high GM-CSF group had significantly higher DAS28-ESR and serum levels of cytokines (IL-17A, IL-1β, IL-6, TNF-α) at baseline, as well as significantly higher rate of non-good response (62.8% vs. 39.4%, P = 0.010) and poor response (27.9% vs. 9.1%, P = 0.004) than the low GM-CSF group at W24. In addition, poor responders had significantly higher levels of GM-CSF with concomitant increase in the serum levels of IL-17A and IL-1β at baseline than those in moderate and good response groups, while serum levels of IL-6 and TNF-α at baseline were not significantly different in three response groups.

CONCLUSION

The high levels of GM-CSF (> 5 ng/ml and > 10 ng/ml) at baseline were the independent predictors of non-good response and poor response to TCZ at W24 respectively. The high level of GM-CSF at baseline is a marker of high disease activity and a predictor of poor response to TCZ in severe RA patients, which may facilitate the development of individualized treatment strategies for refractory RA.

Prognostic and predictive markers of systemic sclerosis-associated interstitial lung disease in a clinical trial and long-term observational cohort

OBJECTIVES

To explore prognostic and predictive markers of SSc-associated interstitial lung disease (SSc-ILD) outcomes in a phase 3 trial (focuSSced) and prognostic markers in a real-world cohort (SMART).

METHODS

The focuSSced SSc-ILD subgroup included 68 of 106 placebo-treated and 68 of 104 tocilizumab-treated patients. The SMART cohort included 505 patients with SSc-ILD. Linear mixed-effect models were used to identify factors associated with change in forced vital capacity (FVC). Kaplan-Meier estimation and Cox regression were used for time-to-event analyses.

RESULTS

In placebo-treated focuSSced patients, sex was a significant prognostic factor for FVC decline; males had increased risk for absolute decline ≥10% in percent-predicted FVC (ppFVC) and 0.22% faster weekly FVC decline than females (P = 0.0001). FVC was 9.8% lower in patients with CRP >6 mg/ml vs those with CRP ≤6 mg/ml (P = 0.0059). Tocilizumab reduced the risk for ≥10% decline in ppFVC in patients who were male, had earlier disease (<2 years duration), had IL-6 levels <10 pg/ml, or had anti-topoisomerase antibodies (ATA). In the SMART cohort, prognostic factors for ppFVC <70% were male sex, ATA, and low baseline FVC. Males had 3.3% lower FVC 1 year after disease onset (P < 0.001) and 0.6% faster yearly decline (P = 0.03) than females.

CONCLUSION

Prognostic markers in SSc-ILD were similar between focuSSced and SMART. Male sex and inflammatory markers were associated with lower FVC but IL-6 ≥10 pg/ml was not predictive of response to tocilizumab.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02453256.

Inappropriate treatment response to DMARDs: A pathway to difficult-to-treat rheumatoid arthritis

In recent years, difficult-to-treat rheumatoid arthritis (D2T RA) has attracted significant attention from rheumatologists due to its poor treatment response and the persistent symptoms or signs experienced by patients. The therapeutic demands of patients with D2T RA are not properly met due to unclear pathogenic causes and a lack of high-quality data for current treatment options, creating considerable management difficulties with this patient population. This review describes the clinical challenges associated with disease-modifying antirheumatic drugs (DMARDs) and explores contributing factors associated with inappropriate response to DMARDs that may lead to D2T RA and related immunological dysregulation. It is now understood that D2T RA is a highly heterogeneous pathological status that involves multiple factors. These factors include but are not limited to genetics, environment, immunogenicity, comorbidities, adverse drug reactions, inappropriate drug application, poor adherence, and socioeconomic status. Besides, these factors may manifest in the selection and utilization of specific DMARDs, either individually or in combination, thereby contributing to inadequate treatment response. Finding these variables may offer hints for enhancing DMARD therapy plans and bettering the condition of D2T RA patients.

Tofacitinib treatment modulates the levels of several inflammation-related plasma proteins in rheumatoid arthritis and baseline levels of soluble biomarkers associate with the treatment response

The data on the effects of tofacitinib on soluble proteins in patients with rheumatoid arthritis (RA) is currently very limited. We analyzed how tofacitinib treatment and thus inhibition of the Janus kinase-signal transducer and activation of transcription pathway affects the in vivo levels of inflammation-related plasma proteins in RA patients. In this study, 16 patients with active RA [28-joint disease activity score (DAS28) >3.2] despite treatment with conventional synthetic disease-modifying antirheumatic drugs (csDMARDs) started tofacitinib treatment 5 mg twice daily. Levels of 92 inflammation-related plasma proteins were determined by proximity extension assay at baseline and at 3 months. Tofacitinib treatment for 3 months, in csDMARD background, decreased the mean DAS28 from 4.4 to 2.6 (P < 0.001). Marked (>20%) and statistically significant (P < 0.05) changes were found in the levels of 21 proteins, 18 of which decreased and 3 increased. Of these proteins, 17 are directly involved in inflammatory responses or in the cellular response to cytokines. The highest (>50%) decrease was observed for interleukin-6 (IL-6), C-X-C motif chemokine ligand 1, matrix metalloproteinase-1, and AXIN1. Higher baseline levels of IL-6 and lower levels of C-C motif chemokine 11 and Delta and Notch-like epidermal growth factor-related receptors were associated with DAS28 improvement. Our results indicate that tofacitinib downregulates several proinflammatory plasma proteins that may contribute to the clinical efficacy of tofacitinib. In addition, soluble biomarkers may predict the treatment response to tofacitinib.

Genetic Biomarkers as Predictors of Response to Tocilizumab in Rheumatoid Arthritis: A Systematic Review and Meta-Analysis

Rheumatoid arthritis (RA) is a lifelong, debilitating disease which incredibly impacts a patient’s quality of life if not treated to the optimal target. The clinical response of tocilizumab, an interleukin-6 (IL-6) inhibitor, is associated with several gene polymorphisms, particularly targeting the IL-6 pathway. This systematic review and meta-analysis seeks to investigate genetic biomarkers that predict the treatment outcome of tocilizumab therapy in RA patients. After evaluating the quality of retrieved records, five studies were chosen to carry out a quantitative synthesis involving 591 participants. We analysed genetic markers of IL-6R single nucleotide polymorphism (SNP)s rs12083537, rs2228145 and rs4329505, FCGR3A, CD69, GALNT18 and FCGR2A. A plausible finding based on meta-analysis revealed that RA patients with homozygous AA genotype for rs12083537 polymorphism of the IL-6R gene demonstrate a better response to TCZ treatment as opposed to homozygous and heterozygous patients with the G allele. Nonetheless, limitations in evaluating the available studies by meta-analysis include a lack of studies with dissimilarities in study design and outcome definitions, small sample sizes with low statistical power and heterogeneity of cohorts, a restricted the number of tested SNPs and small effects for the selected variants. Inconsistent finding remains as a great challenge to forge ahead towards personalised medicine for RA management.

Toward Overcoming Treatment Failure in Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by inflammation and bone erosion. The exact mechanism of RA is still unknown, but various immune cytokines, signaling pathways and effector cells are involved. Disease-modifying antirheumatic drugs (DMARDs) are commonly used in RA treatment and classified into different categories. Nevertheless, RA treatment is based on a "trial-and-error" approach, and a substantial proportion of patients show failed therapy for each DMARD. Over the past decades, great efforts have been made to overcome treatment failure, including identification of biomarkers, exploration of the reasons for loss of efficacy, development of sequential or combinational DMARDs strategies and approval of new DMARDs. Here, we summarize these efforts, which would provide valuable insights for accurate RA clinical medication. While gratifying, researchers realize that these efforts are still far from enough to recommend specific DMARDs for individual patients. Precision medicine is an emerging medical model that proposes a highly individualized and tailored approach for disease management. In this review, we also discuss the potential of precision medicine for overcoming RA treatment failure, with the introduction of various cutting-edge technologies and big data.

Characterization of clinical, laboratory, IL-6 serum levels, and IL-6-174 G/C genetic polymorphisms in patients with rheumatoid arthritis and Sjögren's syndrome

OBJECTIVE

This study aimed to characterize the clinical (disease activity and exocrine gland function), laboratory, interleukin 6 (IL-6) serum levels, and IL-6-174G/C (rs1800795) genetic polymorphisms among rheumatoid arthritis (RA), RA plus Sjögren's syndrome (RA+SS), and control subjects.

METHODS

A case-control study enrolling 137 women (52±11 years old) were divided into three groups as follows: RA (n=70), RA+SS (n=29), and healthy control (C, n=38). Individuals underwent clinical evaluation composed of Schirmer's test, unstimulated salivary flow rate, and evaluation of disease activity and functional capacity (Disease Activity Score [DAS28] and Health Assessment Questionnaire [HAQ]). IL-6 serum levels and IL-6-174G/C polymorphisms were assessed.

RESULTS

RA and RA+SS presented higher serum levels of IL-6 than controls (p<0.001). Also, higher IL-6 levels were related to swollen joints (p=0.038), limited functional capacity (p=0.004), and disease activity (p≤0.001). However, neither IL-6-174G/C genetic polymorphism nor its allele frequency was associated with RA or RA+SS.

CONCLUSION

IL-6 serum is an important marker of RA activity and functional incapacity, but IL-6-174G/C genetic polymorphism did not differ among healthy controls and cases.

Going Up Inflame: Reviewing the Underexplored Role of Inflammatory Programming in Stress-Induced Intrauterine Growth Restricted Livestock

The impact of intrauterine growth restriction (IUGR) on health in humans is well-recognized. It is the second leading cause of perinatal mortality worldwide, and it is associated with deficits in metabolism and muscle growth that increase lifelong risk for hypertension, obesity, hyperlipidemia, and type 2 diabetes. Comparatively, the barrier that IUGR imposes on livestock production is less recognized by the industry. Meat animals born with low birthweight due to IUGR are beset with greater early death loss, inefficient growth, and reduced carcass merit. These animals exhibit poor feed-to-gain ratios, less lean mass, and greater fat deposition, which increase production costs and decrease value. Ultimately, this reduces the amount of meat produced by each animal and threatens the economic sustainability of livestock industries. Intrauterine growth restriction is most commonly the result of fetal programming responses to placental insufficiency, but the exact mechanisms by which this occurs are not well-understood. In uncompromised pregnancies, inflammatory cytokines are produced at modest rates by placental and fetal tissues and play an important role in fetal development. However, unfavorable intrauterine conditions can cause cytokine activity to be excessive during critical windows of fetal development. Our recent evidence indicates that this impacts developmental programming of muscle growth and metabolism and contributes to the IUGR phenotype. In this review, we outline the role of inflammatory cytokine activity in the development of normal and IUGR phenotypes. We also highlight the contributions of sheep and other animal models in identifying mechanisms for IUGR pathologies.

The association between interleukin-6 promoter polymorphisms and rheumatoid arthritis by ethnicity: A meta-analysis of 33 studies

OBJECTIVE

We performed a meta-analysis to determine the effect Interleukin-6 (IL-6) promoter polymorphism (-174 G>C, -572 G>C, and -597 G>A) have on the development rheumatoid arthritis (RA) by ethnicity.

MATERIAL AND METHODS

PubMed, EBSCO, LILACS, and Scopus databases were searched for studies exploring the association between any IL6 polymorphisms and RA until November 2018. Genotype distributions were extracted and, depending on the level heterogeneity, determined by the ψ²-based Q test and the Inconsistency Index (I²), fixed-effects or random-effects models were used to calculate pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) for the heterozygous, homozygous, dominant, recessive, and allelic genetic models.

RESULTS

From 708 identified publications, 33 were used in this analysis. For the -174 polymorphism, Asians (OR_heterozygous=7.57, 95%CI: 2.28-25.14, OR_homozygous=5.84, 95%CI: 2.06-16.56, OR_dominant=7.21, 95%CI: 2.30-22.63, OR_recessive=5.04, 95%CI: 1.78-14.28, OR_allelic=6.60, 95%CI: 2.26-19.28, p<.05) and Middle East countries (OR_heterozygous=2.30, 95%CI: 1.10-4.81, OR_dominant=2.27, 95%CI: 1.22-4.22, OR_allelic=2.29, 95%CI: 1.24-4.23, p<.05) were associated with a significant risk of developing RA. Whereas, for Latinos, the C-allele was associated with a benefit (OR_homozygous=0.26, 95%CI: .08-.82, OR_recessive=.25, 95%CI: .08-.80, p<.05). For the -572 polymorphism, Asians demonstrated a significant association for the homozygous and recessive genetic models (8 studies, OR_homozygous=1.56, 95%CI: 1.16-2.09, OR_recessive=1.63, 95%CI: 1.08-2.45, p<.05). For the -597 polymorphism, no association was observed.

CONCLUSIONS

Here, the -174 G>C polymorphism increased the risk of developing RA in Asians and Middle East populations. Interestingly, for Latinos, the polymorphism was associated with a benefit. For the -572 polymorphism, only the Asian population showed an increased risk of developing RA for the CC genotype.

Mendelian randomisation and experimental medicine approaches to IL-6 as a drug target in PAH

Background

Inflammation and dysregulated immunity are important in the development of pulmonary arterial hypertension (PAH). Compelling preclinical data supports the therapeutic blockade of interleukin-6 (IL-6) signalling.

Methods

We conducted a phase 2 open-label study of intravenous tocilizumab (8 mg·kg⁻¹) over 6 months in patients with group 1 PAH. Co-primary end-points were safety, defined by incidence and severity of adverse events, and change in pulmonary vascular resistance. Separately, a mendelian randomisation study was undertaken on 11 744 individuals with European ancestry including 2085 patients with idiopathic/heritable disease for the IL-6 receptor (IL6R) variant (rs7529229), known to associate with circulating IL-6R levels.

Results

We recruited 29 patients (male/female 10/19; mean±sd age 54.9±11.4 years). Of these, 19 had heritable/idiopathic PAH and 10 had connective tissue disease-associated PAH. Six were withdrawn prior to drug administration; 23 patients received at least one dose of tocilizumab. Tocilizumab was discontinued in four patients owing to serious adverse events. There were no deaths. Despite evidence of target engagement in plasma IL-6 and C-reactive protein levels, both intention-to-treat and modified intention-to-treat analyses demonstrated no change in pulmonary vascular resistance. Inflammatory markers did not predict treatment response. Mendelian randomisation did not support an effect of the lead IL6R variant on risk of PAH (OR 0.99, p=0.88).

Conclusion

Adverse events were consistent with the known safety profile of tocilizumab. Tocilizumab did not show any consistent treatment effect.

Tocilizumab did not block IL-6 signalling in pulmonary arterial hypertension. Multicentre mendelian randomisation studies additionally did not demonstrate evidence for IL-6R in pulmonary arterial hypertension.https://bit.ly/3xkDxS5

Comparison of the drug retention and reasons for discontinuation of tumor necrosis factor inhibitors and interleukin-6 inhibitors in Japanese patients with elderly-onset rheumatoid arthritis-the ANSWER cohort study

BACKGROUND

This multi-center, retrospective study aimed to clarify retention rates and reasons for discontinuation of either tumor necrosis factor inhibitors (TNFi) or interleukin-6 inhibitors (IL-6i) in patients with elderly-onset rheumatoid arthritis (EORA).

METHODS

Patients with rheumatoid arthritis (RA) enrolled in a Japanese multicenter observational registry between 2011 and 2020 were included. EORA was defined as RA with onset at 60 or over. To adjust confounding by indication for treatment with TNFi or IL-6i, a propensity score based on multiple baseline characteristics variables was used to compare the drug retention and causes for discontinuation between TNFi and IL-6i. Adjusted cumulative incidence of drug discontinuation for each reason was compared between the two groups using the Fine-Gray model.

RESULTS

Among a total of 9,550 patients in the registry, 674 TNFi and 297 IL-6i initiators with EORA were identified. Age, the proportion of females, disease duration, and baseline disease activity at the time of TNFi or IL-6i initiation were similar between the two groups. After adjusting for differences in baseline characteristics between the two groups, overall drug discontinuation was significantly lower in the IL-6i as compared to the TNFi (HR = 0.71, 95%CI = 0.59-0.86, p < 0.001). The adjusted cumulative incidence of discontinuation due to lack of effectiveness was lower with the IL-6i (HR = 0.46, 95%CI = 0.33-0.63, p < 0.001) while those due to adverse events (HR = 0.82, 95%CI = 0.56-1.18, p = 0.28) or achievement of clinical remission (HR = 1.09, 95%CI = 0.62-1.91, p = 0.76) were similar between the two groups.

CONCLUSIONS

In EORA patients initiating a TNFi or IL-6i, significantly higher drug retention was observed with IL-6i. Discontinuation due to lack of effectiveness was significantly less frequent in IL-6i while discontinuations due to adverse event or achievement of clinical remission were similar between the two groups.

C-reactive protein and implications in rheumatoid arthritis and associated comorbidities

C-reactive protein (CRP) is routinely assessed as a marker of systemic inflammation in rheumatoid arthritis (RA). However, it is also an immune regulator that plays an important role in inflammatory pathways associated with RA and promotes atherogenic effects. Comorbidities linked to systemic inflammation are common in RA, and CRP has been associated with the risk for cardiovascular disease, diabetes, metabolic syndrome, pulmonary diseases, and depression. The relationship between systemic inflammation, CRP, and comorbidities in RA is complex, and it is challenging to determine how changing CRP levels may affect the risk or progression of these comorbidities. We review the biological role of CRP in RA and its implications for disease activity and treatment response. We also discuss the impact of treatment on CRP levels and whether reducing systemic inflammation and inhibiting CRP-mediated inflammatory pathways may have an impact on conditions commonly comorbid with RA.

Predicting treatment response to IL6R blockers in rheumatoid arthritis

Patients with severe, active RA who have not responded to conventional therapy may receive biological disease modifying anti-rheumatic drugs (bDMARDs). However, 40% of cases do not achieve complete disease control, resulting in a negative impact on patient quality of life and representing a waste of healthcare resources. Ongoing research seeks to establish biomarkers, which can be used to predict treatment response to biologics in RA to enable more targeted approaches to treatment. However, much of the work has focused on one class of biologic drug, the TNF inhibitors (TNFi). Here, we will review the current state of research to identify biomarkers predictive of response to the class of bDMARDs targeting the IL6R. While success has been limited thus far, serum drug and low ICAM1 levels have shown promise, with associations reported in independent studies. The challenges faced by researchers and lessons learned from studies of TNFi will be discussed.

Assessment of interleukin 6 gene polymorphisms with rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is complex autoimmune system disease and significant impact on the health of population in our world. Numerous studies confirmed that genetic factors play a crucial role in the pathogenesis of RA. In this current study, we aimed to investigate IL-6 polymorphisms and RA risk in Chinese Han population.

METHODS

508 RA patients and 494 age- and gender- matched healthy controls were recruited, all subjects were genotyped with an Agena MassARRAY platform. Subsequently, odds ratios (ORs) and 95% confidence intervals (CIs) were calculated by unconditional logistic regression after adjusting for age and gender.

RESULTS

Our results suggested that IL-6 rs2243289 allele and genotype frequencies were associated with reduced RA risk under all genetic models (all p < 0.05). Stratification analysis revealed that IL-6 rs2243289 polymorphism was significant associated with decreased the risk of RA in the old groups (age > 54) (all p < 0.05). However, IL-6 rs2069837 and rs1800796 polymorphisms were associated with increased risk of RA among the young groups (age ≤ 54) (all p < 0.05). In addition, subgroup analysis by gender suggested that IL-6 rs2069837 and rs1800796 polymorphism were interacted with increased the risk of RA in males (all p < 0.05). Besides, IL-6 rs2243289 was associated with reduced RA risk in females.

CONCLUSIONS

In conclusion, our results demonstrated the correlation between IL and 6 polymorphisms and RA susceptibility and confirmed for the first time that the relationship was restricted to age and gender in Chinese Han population.

Association of High Serum Interleukin-6 Levels With Severe Progression of Rheumatoid Arthritis and Increased Treatment Response Differentiating Sarilumab From Adalimumab or Methotrexate in a Post Hoc Analysis

Objective

The development of biomarkers to guide treatment decisions is a major research focus in rheumatoid arthritis (RA). Patients with RA have elevated interleukin‐6 (IL‐6) levels; however, the utility of IL‐6 as a predictor of treatment response is unclear. This study was undertaken to investigate, by post hoc analysis, whether baseline IL‐6 levels are predictive of sarilumab treatment responses in 2 phase III studies.

Methods

Serum IL‐6 concentrations were measured in patients with RA prior to receiving sarilumab 200 mg (n = 148) or adalimumab 40 mg (n = 152) every 2 weeks (in the MONARCH trial; ClinicalTrials.gov identifier: NCT02332590) or sarilumab 150 mg, sarilumab 200 mg, or placebo every 2 weeks plus methotrexate (MTX) (n = 401, n = 396, and n = 397, respectively) (in the MOBILITY trial; ClinicalTrials.gov identifier: NCT01061736). Efficacy and patient‐reported outcomes were compared between and within groups according to IL‐6 tertile using linear and logistic regression.

Results

In MONARCH, patients with high baseline IL‐6 levels (all ≥3 times the upper limit of normal; n = 100) had higher disease activity at baseline than those with low IL‐6 levels (n = 100). The magnitude of clinical improvement over 24 weeks with sarilumab versus adalimumab was greater in patients with high compared to those with low baseline IL‐6 levels. In MOBILITY, compared to patients with low IL‐6 levels (n = 397), patients with high IL‐6 levels (n = 398) had higher disease activity and joint damage at baseline, were more likely to have joint progression, and had less clinical improvement over 52 weeks’ treatment with placebo plus MTX compared to sarilumab 150 mg or 200 mg plus MTX. Baseline IL‐6 and C‐reactive protein levels were both predictive of outcomes. Safety profiles were similar between defined IL‐6 tertiles.

Conclusion

IL‐6 may be a prognostic marker of disease progression and severity, and patients with high IL‐6 levels may be likely to benefit from sarilumab compared to adalimumab or MTX. Prospective validation is warranted to confirm the results of these post hoc analyses.

Efficacy of baricitinib in treating rheumatoid arthritis: Modulatory effects on fibrotic and inflammatory biomarkers in a real-life setting

BACKGROUND

Baricitinib is a JAK inhibitor that blocks intracellular signalling pathways of inflammatory cytokines recommended for Rheumatoid arthritis (RA) patients not responding to initial treatment. Among RA extrareticular features, interstitial lung involvement is primarly characterized by fibrotic evolution. The aim of the present study was to analyse the effects of baricitinib in a population of RA and RA-ILD patients in a real-life setting, describing any changes in lung function parameters, serum inflammatory biomarkers and fibrotic biomarkers after 6 months of treatment.

MATERIALS AND METHODS

15 patients (median (IQR) 65 (55-66); 13% males and 74% smokers) treated with baricitinib were enrolled. 4 patients (27%) were classified as RA-ILD before baricitinib therapy. Our study is the first to evaluate adipokine levels in RA patients (including a small population with RA-ILD) after six months of baricitinib treatment with a novel multiplex method.

RESULTS

The modulatory effects of baricitinib on lipid mediators were associated with clinical and functional improvement, demonstrated by the significant increase in DLco and KCO percentages after six months of treatment. Baricitinib decreased the systemic inflammation by lowering expression of IL-6 and CRP and reducing ESR and serum concentrations of adiponectin. A significant reduction of KL-6 levels in RA-ILD patients after six months of baricitinib therapy reflects the stability of interstitial lung involvement in these patients.

CONCLUSION

Baricitinib was demonstrated to be a safe immune modulator that reduces the concentrations biomarkers of lung fibrosis and inflammation in RA patients, including a subgroup with interstitial lung involvement.

The Association Between Interleukin-6 Promoter Polymorphisms and Rheumatoid Arthritis by Ethnicity: A Meta-Analysis of 33 Studies

OBJECTIVE

We performed a meta-analysis to determine the effect Interleukin-6 (IL-6) promoter polymorphism (-174 G>C, -572 G>C, and -597 G>A) have on the development rheumatoid arthritis (RA) by ethnicity.

MATERIAL AND METHODS

PubMed, EBSCO, LILACS, and Scopus databases were searched for studies exploring the association between any IL6 polymorphisms and RA until November 2018. Genotype distributions were extracted and, depending on the level heterogeneity, determined by the ψ2-based Q test and the Inconsistency Index (I2), fixed-effects or random-effects models were used to calculate pooled odds ratios (ORs) with 95% confidence intervals (95%CIs) for the heterozygous, homozygous, dominant, recessive, and allelic genetic models.

RESULTS

From 708 identified publications, 33 were used in this analysis. For the -174 polymorphism, Asians (ORheterozygous=7.57, 95%CI: 2.28-25.14, ORhomozygous=5.84, 95%CI: 2.06-16.56, ORdominant=7.21, 95%CI: 2.30-22.63, ORrecessive=5.04, 95%CI: 1.78-14.28, ORallelic=6.60, 95%CI: 2.26-19.28, p<.05) and Middle East countries (ORheterozygous=2.30, 95%CI: 1.10-4.81, ORdominant=2.27, 95%CI: 1.22-4.22, ORallelic=2.29, 95%CI: 1.24-4.23, p<.05) were associated with a significant risk of developing RA. Whereas, for Latinos, the C-allele was associated with a benefit (ORhomozygous=0.26, 95%CI: .08-.82, ORrecessive=.25, 95%CI: .08-.80, p<.05). For the -572 polymorphism, Asians demonstrated a significant association for the homozygous and recessive genetic models (8 studies, ORhomozygous=1.56, 95%CI: 1.16-2.09, ORrecessive=1.63, 95%CI: 1.08-2.45, p<.05). For the -597 polymorphism, no association was observed.

CONCLUSIONS

Here, the -174 G>C polymorphism increased the risk of developing RA in Asians and Middle East populations. Interestingly, for Latinos, the polymorphism was associated with a benefit. For the -572 polymorphism, only the Asian population showed an increased risk of developing RA for the CC genotype.

Defining response to TNF-inhibitors in rheumatoid arthritis: the negative impact of anti-TNF cycling and the need for a personalized medicine approach to identify primary non-responders

Current guidelines recommend treating rheumatoid arthritis (RA) patients to reach low disease activity or remission, however, most biologic-naive RA patients fail to reach treatment targets on their first biologic therapy. Approximately 90% of biologic-naive RA patients receive a tumor necrosis factor alpha inhibitor (anti-TNF) as their first biologic treatment, even though several alternative mechanism of action (MOA) therapies are approved as first-line options. After 3 months of therapy, patients may remain on anti-TNF therapy even if they fail to achieve the treatment target, mainly due to formulary structures. This means patients have to endure a second and even a third ineffective anti-TNF-called anti-TNF cycling-before changing MOA. This significantly delays patients from reaching their treatment targets. All anti-TNF drugs target the same molecular and inflammatory pathways; thus, it is not surprising that most patients who are primary non-responders to their initial anti-TNF therapy fail to achieve their treatment targets when cycled through alternative anti-TNFs. This suggests that primary non-responders should be switched to an alternative MOA therapy rather than enduring anti-TNF cycling. Avoiding anti-TNF cycling would prevent disease progression and improve quality of life for RA patients who are primary non-responders to anti-TNFs. The development of a personalized medicine approach to identify primary non-responders to anti-TNFs prior to treatment would allow significantly more patients to reach their treatment target by treating them with alternative MOA therapies as first-line therapies.

Identification of pathological RA endotypes using blood-based biomarkers reflecting tissue metabolism. A retrospective and explorative analysis of two phase III RA studies

There is an increasing demand for accurate endotyping of patients according to their pathogenesis to allow more targeted treatment. We explore a combination of blood-based joint tissue metabolites (neoepitopes) to enable patient clustering through distinct disease profiles. We analysed data from two RA studies (LITHE (N = 574, follow-up 24 and 52 weeks), OSKIRA-1 (N = 131, follow-up 24 weeks)). Two osteoarthritis (OA) studies (SMC01 (N = 447), SMC02 (N = 81)) were included as non-RA comparators. Specific tissue-derived neoepitopes measured at baseline, included: C2M (cartilage degradation); CTX-I and PINP (bone turnover); C1M and C3M (interstitial matrix degradation); CRPM (CRP metabolite) and VICM (macrophage activity). Clustering was performed to identify putative endotypes. We identified five clusters (A-E). Clusters A and B were characterized by generally higher levels of biomarkers than other clusters, except VICM which was significantly higher in cluster B than in cluster A (p<0.001). Biomarker levels in Cluster C were all close to the median, whilst Cluster D was characterised by low levels of all biomarkers. Cluster E also had low levels of most biomarkers, but with significantly higher levels of CTX-I compared to cluster D. There was a significant difference in ΔSHP score observed at 52 weeks (p<0.05). We describe putative RA endotypes based on biomarkers reflecting joint tissue metabolism. These endotypes differ in their underlining pathogenesis, and may in the future have utility for patient treatment selection.

The combination of IL-6 and its soluble receptor is associated with the response of rheumatoid arthritis patients to tocilizumab

BACKGROUND

IL-6 contributes significantly to the chronic inflammatory process of rheumatoid arthritis (RA). Tocilizumab, a humanized anti-human IL-6 receptor antibody that blocks the signaling originated by the IL-6/IL-6R complex, is an effective treatment. However, predictors of the response to tocilizumab are still required. We aimed to combine IL-6 and soluble IL-6R (sIL-6R) levels to identify groups of responses.

METHODS

Heparinized blood and clinical data from 63 RA patients were collected before treatment and after 3 and 6 months. Two-step clustering (SPSS v.18) was used to establish the relationship between IL-6 and sIL-6R. Then, we compared European League Against Rheumatism (EULAR) response criteria with remission achievement in the groups of patients.

RESULTS

Three statistical significant clusters of RA patients (i.e., g1, g2, and g3) were defined by serum concentrations of IL-6 and sIL-6R at baseline. All groups of RA patients had higher IL-6 and sIL-6R levels than healthy donors. The levels of IL-6 expressed as median (IQR) in g1 patients were 124(90-183)pg/ml, in g2 12.3(4.4-24)pg/ml, and in g3 60.1(30-146)pg/ml (p < 0.001). The levels of sIL-6R expressed as mean ± sd in g1 patients were 250.5 ± 72ng/ml, in g2 269.1 ± 125ng/ml, and in g3 732.7 ± 243ng/ml (p < 0.001). Disease activity score (DAS)28, C-reactive protein, and erythrocyte sedimentation rate were comparable in the three groups at baseline. Disease duration in g3 was the longest (median(IQR) years: g1 = 11(5-15), g2 = 12(8-20), and g3 23(16-26); p = 0.006), with years of disease evolution being correlated with sIL-6R levels (R = 0.417, p < 0.001). Simple and Clinical Disease Activity Index (SDAI and CDAI) decreased significantly in the three groups. However, EULAR response criteria and remission achievement at 6m was different in the three groups (p = 0.03 and 0.04, respectively). In all. 17 out of the 18 patients in g1 had a good or moderate response to tocilizumab. Conversely, the percentage of patients with no response to tocilizumab was higher in g3 than in g1 and g2. We also observed different changing patterns of IL-6 and sIL-6R levels among the three groups.

CONCLUSIONS

RA patients could be easily stratified prior to therapeutic intervention with two molecules related to the pathway blocked by tocilizumab. G1 patients, who had the best response to tocilizumab, had the highest level of IL-6 and the lowest level of sIL-6R.

Right drug, right patient, right time: aspiration or future promise for biologics in rheumatoid arthritis?

Individualising biologic disease-modifying anti-rheumatic drugs (bDMARDs) to maximise outcomes and deliver safe and cost-effective care is a key goal in the management of rheumatoid arthritis (RA). Investigation to identify predictive tools of bDMARD response is a highly active and prolific area of research. In addition to clinical phenotyping, cellular and molecular characterisation of synovial tissue and blood in patients with RA, using different technologies, can facilitate predictive testing. This narrative review will summarise the literature for the available bDMARD classes and focus on where progress has been made. We will also look ahead and consider the increasing use of 'omics' technologies, the potential they hold as well as the challenges, and what is needed in the future to fully realise our ambition of personalised bDMARD treatment.

Relationship Between Baseline and Early Changes in C-Reactive Protein and Interleukin-6 Levels and Clinical Response to Tocilizumab in Rheumatoid Arthritis

Objective

To clarify the relevance of measuring interleukin‐6 (IL‐6) and C‐reactive protein (CRP) levels in order to predict clinical response to tocilizumab (TCZ) in rheumatoid arthritis patients.

Methods

In a pooled, post hoc analysis of 5 pivotal trials of TCZ, we examined the distributions of baseline serum concentrations of IL‐6 and CRP, stratified by randomized treatment group, and week 24 Disease Activity Score in 28 joints (DAS28) status (DAS28 <2.6 versus DAS28 ≥2.6). Relationships between early biomarker changes and later changes in DAS28 scores were evaluated using Spearman's correlations and scatterplots. Finally, percentage changes from baseline in IL‐6 and CRP levels were evaluated.

Results

Distributions of baseline IL‐6 and CRP levels were similar for patients who achieved DAS28 scores <2.6 within 6 months of TCZ initiation and those who did not. Correlations between early changes in these 2 biomarkers and change in DAS28 scores were low (rho < 0.3 for all). Mean percentage increases from baseline in IL‐6 concentrations were observed in all treatment groups (highest in the 8 mg/kg dose group); mean percentage decreases in CRP concentrations were greater at week 2 and at all visits for the 8 mg/kg dose group.

Conclusion

Baseline serum concentrations of IL‐6 and CRP may not be predictive of clinical outcomes after TCZ treatment. Data demonstrate the efficacy of TCZ in patients across a broad range of baseline serum IL‐6 and CRP concentrations. Similarly, changes in these biomarkers after TCZ dosing are expected and may or may not correspond to changes in other clinical signs and symptoms. These results complement previous reports describing the complex interactions among biomarker changes, other therapeutic mechanisms of action, and clinical outcomes.

Molecular modeling and SPRi investigations of interleukin 6 (IL6) protein and DNA aptamers

Interleukin 6 (IL6), an inflammatory response protein has major implications in immune-related inflammatory diseases. Identification of aptamers for the IL6 protein aids in diagnostic, therapeutic, and theranostic applications. Three different DNA aptamers and their interactions with IL6 protein were extensively investigated in a phosphate buffed saline (PBS) solution. Molecular-level modeling through molecular dynamics provided insights of structural, conformational changes and specific binding domains of these protein-aptamer complexes. Multiple simulations reveal consistent binding region for all protein-aptamer complexes. Conformational changes coupled with quantitative analysis of center of mass (COM) distance, radius of gyration (R_g), and number of intermolecular hydrogen bonds in each IL6 protein-aptamer complex was used to determine their binding performance strength and obtain molecular configurations with strong binding. A similarity comparison of the molecular configurations with strong binding from molecular-level modeling concurred with Surface Plasmon Resonance imaging (SPRi) for these three aptamer complexes, thus corroborating molecular modeling analysis findings. Insights from the natural progression of IL6 protein-aptamer binding modeled in this work has identified key features such as the orientation and location of the aptamer in the binding event. These key features are not readily feasible from wet lab experiments and impact the efficacy of the aptamers in diagnostic and theranostic applications.

Serum tocilizumab trough concentration can be used to monitor systemic IL-6 receptor blockade in patients with rheumatoid arthritis: a prospective observational cohort study

OBJECTIVES

To investigate the pharmacokinetics (PK) and dynamics of tocilizumab (TCZ) in daily practice.

METHOD

An observational study of 66 consecutive RA patients treated with TCZ 8 mg/kg once every 4 weeks intravenously, monitored for 24 weeks. Spearman's rank test was used to investigate the correlation between TCZ concentration and C-reactive protein (CRP). Clinical improvement was assessed at week 24 using the Disease Activity Score in 28 joints (DAS28) compared to baseline, and its relationship with TCZ concentration was investigated using linear regression analyses. TCZ trough concentrations and anti-drug antibodies were measured using an enzyme-linked immunosorbent assay (ELISA) and antigen binding test, respectively.

RESULTS

At baseline, 26 patients (39.4%) had a CRP level above 10 mg/L with a median (interquartile range, IQR) of 37.7 (21.9-49.7) mg/L. A TCZ concentration above 1 mg/L was sufficient to normalize CRP levels. Spearman's rank test showed a correlation coefficient of -0.460 (p < 0.0001). The TCZ concentration varied widely, with concentrations < 1 mg/L in 17-31% of patients, depending on the time point of measurement. Anti-TCZ antibodies were detected in one sample. Linear regression analyses showed a coefficient of 0.080 with a 95% confidence interval (CI) of 0.039-0.113 (p < 0.001) for the association between TCZ concentration and ΔDAS28. No confounders were identified.

CONCLUSIONS

The TCZ standard regimen results in a wide variety of serum TCZ trough concentrations; this is mostly due to target binding and to a lesser extent to immunogenicity. The majority of patients obtained TCZ concentrations > 1 mg/L, which is sufficient for CRP normalization. Therefore, dose taper strategies might be possible in a substantial proportion of patients.

Circulating interleukin-6 and rheumatoid arthritis: A Mendelian randomization meta-analysis

Interleukin-6 (IL-6), as a pleiotropic cytokine, has been demonstrated to be closely associated with the pathogenisis of rheumatoid arthritis (RA). However, whether this association is causal or not remains unclear, because of the multifactorial role of IL-6 and related confounding factors. We aimed to evaluate the causal relevance between circulating IL-6 levels and the risk of RA through meta-analytical Mendelian randomization approach. IL-6 gene -174G/C variant was selected as an instrument in this Mendelian randomization meta-analysis. Article identification and data collection were conducted in duplicate and independently by 2 authors. The STATA software was used for data analysis. In total, 15 and 5 articles on the association of the -174G/C variant with RA risk and circulating IL-6 level, respectively, were included. The overall analysis showed that C allelic and GC+CC genotype were significantly with 1.59-fold (95% CI: 1.19-2.14) and 1.63-fold (95% CI: 1.17-2.26) increased risk of developing RA, respectively. Asian populations showed stronger association with 4.55-fold (95% CI: 1.62-12.75), 1.84-fold (95% CI: 1.13-2.99), and 4.69-fold (95% CI: 1.68-13.14) increased RA risk in carriers of -174C allelic, CC, and GC+CC genotype, respectively. Carriers of GC+CC genotype showed significant reduction in the circulating IL-6 level compared with GG carriers (WMD = -0.77; 95% CI: -1.16 to -0.38; P = 0.000) in overall populations. Mendelian randomization presented 6% and 22% increased risk of RA with 0.1 pg/mL reduction of circulating IL-6 level in overall and Asian populations, respectively. This Mendelian randomization meta-analysis demonstrated that the long-term genetically reduced circulating IL-6 level might be causally related to a higher risk of RA, especially in Asian populations.

Personalized medicine in rheumatoid arthritis: is the glass half full or half empty?

The care of patients with rheumatoid arthritis (RA) has been revolutionized since the 1990s. Strict monitoring and disease control based on measurement of signs and symptoms towards a target of low disease activity have improved outcome of patients enormously. As a result of treatment strategies based upon individualized measurement of disease activity, the clinical view of RA has changed from a destructive autoimmune disease (with a median joint damage of >10 Sharp units per year) to a condition in which significant damage can be prevented in the majority of patients. Moreover, a large number of targeted therapies (tumour necrosis factor, IL6, CD80/CD86 and CD20 inhibitors) have become available to better treat the underlying disease process. However, identification of the underlying pathways that drive the disease process in an individual patient has been relatively unsuccessful, implying that no predictive factors have been identified to guide the choice of a specific treatment. Distinct subsets of RA patients have been identified, based on the presence or absence of anticitrullinated protein antibodies (ACPAs). These two subsets are associated with different environmental and genetic risk factors, histology and disease outcome (a more destructive disease course with more persistent joint inflammation is observed when ACPAs are present). Therefore, it is recommended that treatment should be guided towards a more consistently low level of disease activity in the presence of ACPAs than in the absence of the antibodies.

Seronegative rheumatoid arthritis: pathogenetic and therapeutic aspects

Rheumatoid arthritis (RA) has long been recognised as a highly heterogeneous disease of immune dysregulation. Despite an ever-growing appreciation of the role of circulating autoantibodies in the development of 'seropositive' disease, the pathogenesis of seronegative RA remains poorly understood. Accumulating evidence suggests that RA 'serotypes', in fact, reflect distinct disease entities that, despite their clinical overlap, diverge in respect of genetic architecture, cellular pathology and even therapeutic responsiveness. Focussing on seronegative RA, this review considers these concepts and their implications for the management of patients with this challenging, though sometimes overlooked, condition.

Intravenous tocilizumab: a review of its use in adults with rheumatoid arthritis

Tocilizumab (Actemra®, RoActemra®) is a humanized monoclonal antibody that acts as an interleukin-6 receptor antagonist. Intravenous tocilizumab as monotherapy or in combination with disease-modifying anti-rheumatic drugs (DMARDs) is indicated for the treatment of adult patients with moderate to severe active rheumatoid arthritis (RA) who had an inadequate response to one or more DMARDs or tumor necrosis factor (TNF) α antagonists (the specific indication varies between countries); it may also be used as monotherapy in patients for whom continued methotrexate use is inappropriate. This article reviews the efficacy and tolerability of tocilizumab in these patients and briefly summarizes its pharmacology. Several large well-designed clinical trials and routine clinical practice studies showed that tocilizumab was an effective and generally well tolerated biologic for the treatment of adults with RA, including those with an inadequate response to DMARDs or TNFα antagonists. In these studies, tocilizumab as monotherapy or in combination with DMARDs (including methotrexate) had beneficial effects on the signs and symptoms of disease, health-related quality of life/physical function, and/or radiologic disease progression. In addition, tocilizumab monotherapy was more effective than adalimumab monotherapy in improving the signs and symptoms of disease in patients for whom continued methotrexate use was inappropriate. As with other biologic DMARDS, infections were the most common adverse event associated with tocilizumab therapy. Pooled and meta-analyses demonstrated that the efficacy and tolerability profile of tocilizumab was sustained during long-term (up to 9 years) therapy. Although additional comparative data are needed to position tocilizumab more definitively with respect to other biologic DMARDs, current evidence indicates that tocilizumab is effective as a first- or subsequent-line biologic in patients with moderate to severe RA.

Clinical biomarkers and pathogenic-related cytokines in rheumatoid arthritis

Rheumatoid arthritis (RA) is a common autoimmune disease with unknown etiology and pathogenesis. Although major therapeutic advances have been made in recent years, there is no cure for the disease. Current medications mainly reduce inflammation in order to relieve pain and slow joint damage, but many have potentially serious side effects. Therefore, to find specific biomarkers will benefit both RA patients to find relief from the disease and physicians to monitor the disease development. A number of biomarkers have been discovered and used clinically, and others are still under investigation. The autoantibodies, which are widely used in diagnosis and prognosis, novel biomarkers, which reflect clinical disease activity, and newly found biomarkers and pathogenic-related cytokines are discussed in this review.

Drug delivery options to increase patient adherence and satisfaction in the management of rheumatoid arthritis -- focus on subcutaneous tocilizumab

Rheumatoid arthritis (RA) is a chronic, progressive, inflammatory disease associated with joint destruction. Tocilizumab (TCZ) is a humanized monoclonal anti-interleukin-6 receptor antibody that was initially developed for use as an intravenous (IV) infusion. Previous studies have shown that TCZ-IV is an important treatment option in patients with moderate-to-severe RA. A subcutaneous (SC) formulation of 162 mg TCZ that was recently developed and approved provides an additional treatment option for RA patients. In the present review, we provide an update on the efficacy and safety of TCZ-SC, compared with TCZ-IV. The TCZ-SC doses of 162 mg every 2 weeks (q2w) or weekly (qw) were selected based on pharmacokinetic and pharmacodynamic studies. Both TCZ-SC q2w and qw regimens showed equivalent effects to TCZ-IV in most patients; however, the TCZ-SC qw regimen consistently showed a more rapid effect in terms of C-reactive protein normalization. Randomized controlled studies showed that TCZ-SC monotherapy or combined with disease-modifying antirheumatic drugs demonstrated comparable efficacy to TCZ-IV in patients who were both biologic-naïve and refractory to tumor necrosis factor inhibitors. TCZ-SC at both qw and q2w were generally well-tolerated for up to 24 weeks. There was a low rate of withdrawal due to adverse events, and their incidence was comparable with that seen with TCZ-IV. An injection site reaction was seen in approximately 10% of patients who received the subcutaneous formulation. In conclusion, although clinical results are still limited, the currently available evidence suggests that TCZ-SC is a promising treatment for moderate-to-severe RA, both as monotherapy and combination therapy. More data is needed to determine the optimal dosing schedule.

Hypomethylation of interleukin 6 correlates with renal involvement in systemic lupus erythematosus

OBJECTIVE

To analyze peripheral blood interleukin 6 (IL-6) methylation status and its clinical significance in patients with systemic lupus erythematosus (SLE).

MATERIAL AND METHODS

Blood samples from 41 adult patients with SLE, and 20 healthy controls were collected. The methylation status of IL-6 was determined by methylation specific polymerase chain reaction (MSP). The IL-6 expression was detected by real-time PCR. Correlations between IL-6 methylation status and clinical features or laboratory findings in patients with SLE were investigated.

RESULTS

The methylation status and expression of IL-6 in peripheral blood could reflect the level in peripheral blood mononucleated cells (PBMCs) of SLE. Significantly positive correlation was found between IL-6 hypomethylation and renal disorder. Interleukin 6 hypomethylation was found negatively correlated with serum C3.

CONCLUSIONS

The detection of IL-6 methylation status in peripheral blood could reflect the status in PBMC with SLE. Interleukin 6 may play a role in renal disorder with SLE patients. Interleukin 6 could be considered as a new biomarker for predicting SLE flare.

The effects of gene polymorphisms in interleukin-4 and interleukin-6 on the susceptibility of rheumatoid arthritis in a Chinese population

BACKGROUND

Interleukin-4 (IL-4) and interleukin-6 (IL-6) have been reported to associate with pathogenesis of rheumatoid arthritis (RA); however, the role of IL-4 and IL-6 genetic polymorphisms in RA remains unknown.

METHOD

A total of 752 unrelated Chinese patients with RA and 798 healthy Chinese volunteers with no family histories of any autoimmune diseases were recruited. The promoter IL-4-590 C/T and IL-6-174 G/C polymorphisms were genotyped.

RESULT

The genotype distributions and allele frequencies of IL-4-590 C/T and IL-6-174 G/C polymorphisms in RA patients were significantly different from healthy volunteers. Statistically significant differences were observed in genotypes for IL-4-590 and IL-6-174. The frequencies of both the T allele on the IL-4-590 and the C on the IL-6-174 were significantly increased in RA patients.

CONCLUSION

The IL-4-590 and IL-6-174 promoter polymorphisms may be associated with increased risk of RA and could be used as genetic marker for assessing the susceptibility and severity of RA in Chinese.

Interleukin-6 signal transduction and its role in hepatic lipid metabolic disorders

Hepatic lipid dysregulation can lead to spectrum of metabolic disease conditions including metabolic syndrome (MS), fatty liver and diabetes. Liver lipids are regulated by a complex set of extra-hepatic and intra-hepatic factors including cellular cross-talk with variety of cells, inducing various cytokines. Interleukin 6(IL-6) is a pleiotropic cytokine that exerts both pro-inflammatory and anti-inflammatory effects on hepatic system through either JNK/STAT or ERK/MAPK signaling. Although, IL-6 has shown to protect the liver from fat storage in both rodent and human models and various IL-6(-/-) studies have supported this notion yet a question remains over its deleterious pro-inflammatory effects on hepatocytes. IL-6 ability to produce reactive oxygen species (ROS) and subsequently disturb the hepatic lipid balance has created a conundrum. Furthermore, IL-6 has shown to behave differently under different disease states within hepatocytes and hence, modulating the hepatic lipids accordingly. This review deals with the role of IL-6 on hepatic lipid metabolism and analyzes various data presented on this topic.

Predictive factors of response to biological disease modifying antirheumatic drugs: towards personalized medicine

Many therapies are now available for patients with rheumatoid arthritis (RA) who have an inadequate response to methotrexate including tumor necrosis factor inhibitors, abatacept, tocilizumab, and rituximab. Clinical response to drugs varies widely between individuals. A part of this variability is due to the characteristics of the patient such as age, gender, concomitant therapies, body mass index, or smoking status. Clinical response also depends on disease characteristics including disease activity and severity and presence of autoantibodies. Genetic background, cytokine levels, and immune cell phenotypes could also influence biological therapy response. This review summarizes the impact of all those parameters on response to biological therapies.