The need for prognosticators in rheumatoid arthritis. Biological and clinical markers: where are we now?

Maintenance to target was associated with radiological outcomes in patients with rheumatoid arthritis: a real-world observational cohort study

OBJECTIVE

To investigate the effect of different maintenance to target on radiologic outcomes in patients with rheumatoid arthritis (RA) in real-world setting.

METHODS

RA patients enrolled were screened from a longitudinal cohort. The radiographies were evaluated at baseline, after 1-2 years and thereafter every 2 years. An increase of mTSS > 3 from baseline was taken as the primary outcome and accelerated annual radiological progression as the secondary outcome of radiological progression. The maintenance rate (MR) to target was calculated as the proportion of the year fulfilling preset criteria of target over the whole follow-up period. COX regression and logistic analysis were used to determine the effect of variables on radiological outcomes.

RESULTS

Two hundred forty-three patients were enrolled, with median follow-up of 2 years (3.00). Radiological progression was observed in 43 (17.7%) patients, with annual increase of mTSS 0.20 (1.33). In multivariate analysis, MR was the only independent protective factor of both primary and secondary radiological outcomes in two models [HR 0.09, 95% CI (0.04, 0.22), p < 0.001, model 1; OR 0.21, 95% CI (0.09, 0.49), p < 0.001, model 2]. ACPA positivity was another independent risk factor of secondary outcome [OR 2.96, 95% CI (1.27, 6.86), p = 0.012]. Higher MR was also associated with less radiological progression in established RA patients. Partial MR was not inferior to full maintenance within 4 years in terms of halting radiological progression.

CONCLUSION

Low MR and ACPA positivity were independent risk factors of poor radiological outcomes in RA patients. No significant difference in radiological progression could be detected between partial and full maintenance group within 4 years in daily practice.

KEY POINTS

• The first study showing that maintenance to target is beneficial to bone protection in established RA patients in real-world setting • No difference in radiological outcomes between partial and full maintenance group within 4 years.

Cognitive behavioural therapy for insomnia in patients with rheumatoid arthritis: protocol for the randomised, single-blinded, parallel-group Sleep-RA trial

BACKGROUND

More than half of patients with rheumatoid arthritis complain of insomnia, which is predominantly treated with hypnotic drugs. However, cognitive behavioural therapy for insomnia is recommended as the first-line treatment in international guidelines on sleep. Patients with rheumatoid arthritis suffer from debilitating symptoms, such as fatigue and pain, which can also be linked to sleep disturbance. It remains to be determined whether cognitive behavioural therapy for insomnia can be effective in patients with rheumatoid arthritis. The aim of the Sleep-RA trial is to investigate the efficacy of cognitive behavioural therapy for insomnia on sleep and disease-related symptoms in patients with rheumatoid arthritis. The primary objective is to compare the effect of cognitive behavioural therapy for insomnia relative to usual care on changes in sleep efficiency from baseline to week 7 in patients with rheumatoid arthritis. The key secondary objectives are to compare the effect of cognitive behavioural therapy for insomnia relative to usual care on changes in sleep onset latency, wake after sleep onset, total sleep time, insomnia, sleep quality, fatigue, impact of rheumatoid arthritis and depressive symptoms from baseline to week 26 in patients with rheumatoid arthritis.

METHODS

The Sleep-RA trial is a randomised controlled trial with a two-group parallel design. Sixty patients with rheumatoid arthritis, insomnia and low-to-moderate disease activity will be allocated 1:1 to treatment with cognitive behavioural therapy for insomnia or usual care. Patients in the intervention group will receive nurse-led, group-based cognitive behavioural therapy for insomnia once a week for 6 weeks. Outcome assessments will be carried out at baseline, after treatment (week 7) and at follow-up (week 26).

DISCUSSION

Data on treatment of insomnia in patients with rheumatoid arthritis are sparse. The Sleep-RA trial is the first randomised controlled trial to investigate the efficacy of cognitive behavioural therapy for insomnia in patients with rheumatoid arthritis. Because symptoms of rheumatoid arthritis and insomnia have many similarities, we also find it relevant to investigate the secondary effects of cognitive behavioural therapy for insomnia on fatigue, impact of rheumatoid arthritis, depressive symptoms, pain, functional status, health-related quality of life and disease activity. If we find cognitive behavioural therapy for insomnia to be effective in patients with rheumatoid arthritis this will add weight to the argument that evidence-based non-pharmacological treatment for insomnia in rheumatological outpatient clinics is eligible in accordance with the existing international guidelines on sleep.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT03766100. Registered on 30 November 2018.

Insights into the treatment of rheumatoid arthritis: A paradigm in medicine

Insights into rheumatoid arthritis (RA) have slowly evolved over the last century, but with breathtaking speed over the last 2 decades. While only aspirin and parenteral gold were available in early 20th century, the efficacy of sulfasalazine, glucocorticoids and methotrexate was established around its middle. Identification of pathogenetic pathways was slow, and until today the role of T-cells is enigmatic, while it is clear that genetics via the shared epitope and other genes as well as environmental factors including the metagenome play major roles. More clarity evolved on importance of proinflammatory cytokines, especially TNF and IL-6. The activation of osteoclasts, the culprits of bony joint damage, is amplified by the proinflammatory cytokines. The realization of TNF's central role led to the successful introduction of TNF-inhibitors and subsequently also inhibitors of other cytokines and cells as well as signal transduction. In parallel, the evolution of outcomes research has contributed importantly to RA management. At the turn to the 21st century, improvement criteria and continuous indices were created, allowing reliable therapeutic response determination, including definition of endpoints like remission. Also our understanding of the role of disease activity relative to disease pathology has increased, ultimately fostering the treat-to-target concept and recommendations and, thus, optimal outcomes for RA patients as never been seen before. Similar developments are now ultimately being introduced in the field of psoriatic arthritis. Here many of these aspects are reviewed from a very personal perspective of the author in the hopes of further helping parients with chronic forms of arthritis.

Autoantibodies, C-reactive protein, erythrocyte sedimentation rate and serum cytokine profiling in monitoring of early treatment

Introduction

Currently used clinical scale and laboratory markers to monitor patients with early rheumatoid arthritis (RA) seem to be not sufficient. It has been demonstrated that disease- related cytokines may be elevated very early in RA development and cytokines are considered as the biomarkers potentially useful for RA monitoring.

Material and methods

The group of patients with undifferentiated arthritis (UA) developing RA (UA→RA) was identified from a total of 121 people with arthralgia. UA→RA (n = 16) and healthy control (n = 16) subjects underwent clinical and laboratory evaluation, including acute phase reactants (APRs) and autoantibodies. Cytokines IFN-γ, IL-10, TNF, IL-17A, IL-6, IL-1b, IL-2 in sera were assayed using flow cytometric bead array test.

Results

34.5% of patients with UA developed RA. DAS28 reduced as early as 3 months after initiation of treatment. No DAS28 difference between groups of autoantibody (RF, anti-CCP, ANA-HEp-2) -positive and -negative patients was observed, however, comparing groups of anti-CCP and RF-double negative and -double positive patients, the trend of sooner clinical improvement was visible in the second abovementioned group. After the treatment introduction, the ESR level reduced significantly, while CRP level reduction was not significant. Serum cytokine levels of IL-10, IL-6 and IL-17A reduced after 6 months since introduction of treatment. The positive correlations between ESR, CRP and specific cytokine levels were observed.

Conclusions

The autoantibody and APR profile is poorly connected with the RA course. The serum cytokine profile change in the course of RA and may be potentially used for optimization of RA monitoring.

Increased baseline RUNX2, caspase 3 and p21 gene expressions in the peripheral blood of disease-modifying anti-rheumatic drug-naïve rheumatoid arthritis patients are associated with improved clinical response to methotrexate therapy

OBJECTIVE

To investigate the potential of the baseline gene expression in the whole blood of disease-modifying anti-rheumatic drug-naïve rheumatoid arthritis (RA) patients for predicting the response to methotrexate (MTX) treatment.

METHODS

Twenty-six control subjects and 40 RA patients were examined. Clinical, immunological and radiographic parameters were assessed before and after 24 months of follow-up. The gene expressions in the whole blood were measured using real-time reverse transcription polymerase chain reaction. The protein concentrations in peripheral blood mononuclear cells were quantified using enzyme-linked immunosorbent assay. Receiver operating characteristic curve analyses were used to suggest thresholds that were associated with the prediction of the response.

RESULTS

Decreases in the disease activity at the end of the study were accompanied by significant increases in joint space narrowing score (JSN). Positive correlations between the expressions of the Unc-51-like kinase 1 (ULK1) and matrix metalloproteinase 9 (MMP-9) genes with the level of C-reactive protein and MMP-9 expression with Disease Activity Score of 28 joints (DAS28) and swollen joint count were noted at baseline. The baseline tumor necrosis factor (TNF)α gene expression was positively correlated with JSN at the end of the follow-up, whereas p21, caspase 3, and runt-related transcription factor (RUNX)2 were correlated with the ΔDAS28 values.

CONCLUSIONS

Our results suggest that the expressions of MMP-9 and ULK1 might be associated with disease activity. Increased baseline gene expressions of RUNX2, p21 and caspase 3 in the peripheral blood might predict better responses to MTX therapy.

Heterogeneity of the cytokinome in undifferentiated arthritis progressing to rheumatoid arthritis and its change in the course of therapy. Move toward personalized medicine

OBJECTIVES

To conduct a comprehensive analysis of cytokine concentrations in sera and mononuclear cell supernatants in order to examine inter- and intra-individual cytokine variations in undifferentiated arthritis progressing to rheumatoid arthritis and healthy control groups.

METHODS

Patients with UA (undifferentiated arthritis) developing RA (rheumatoid arthritis) (UA→RA) (n=16) and healthy controls (n=16) were enrolled into the study. UA→RA patients were followed up for six months since the final RA diagnosis. Cytokines IFN-γ, IL-10, TNF, IL-17A, IL-6, IL-1β, IL-2 in sera and mononuclear cell supernatants in 72h and 120h culture variants with- and without anti-CD3 stimulations were assayed using flow cytometric bead array.

RESULTS

The cytokine profile of UA→RA differs from the healthy individual cytokine profile. It is possible to observe specific cytokine pattern characterizing each patient, which alters during course of disease. Specifically, we can distinguish three UA→RA cohorts: the group of patients susceptible to the therapy, characterized by the drop of cytokine levels between 1st and 3rd visit with visible decrease of cytokines in 2nd visit and then secondary slighter increase in 3rd visit; the group of patients refractory or clinically worsening on the therapy, characterized by the highest cytokine levels at 2nd visit with secondary decrease in 3rd visit; and the group of patients with variable responses to the therapy without any specific common cytokine pattern. The cytokine patterns in supernatants of PBMC stimulated anti-CD3 for 72h and 120h are very similar.

CONCLUSIONS

The personal profile including multiplexed cytokine patterns in serum and supernatant may be potentially used for optimization of therapy introduction and monitoring.

Treatment of rheumatoid arthritis with biologics may exacerbate HTLV-1-associated conditions: A case report

RATIONALE

There are roughly 5 to 10 million persons infected with human T-lymphotropic virus type 1 (HTLV-1) worldwide, and the safety of treating this population with biologics remains poorly understood.

PATIENT CONCERNS AND DIAGNOSIS

An HTLV-1-infected 66-year-old female with HTLV-1 uveitis (HU) and HTLV-1-associated myelopathy/tropical spastic paraparesis (HAM/TSP). Her HU had been in remission and her HAM/TSP symptoms had been managed effectively with oral steroids for years. However, she developed severe rheumatoid arthritis (RA) after failing to respond well to conventional anti-rheumatic agents.

INTERVENTIONS

She was administered two intravenous 8mg/kg doses of the biologic tocilizumab.

OUTCOMES

Subsequently, her RA symptoms resolved, but she suffered a recurrence of HU and exacerbation of HAM/TSP symptoms. When she was switched back to steroid-based treatment, HU and HAM symptoms both improved, but RA symptoms again worsened. Finally, an attempt to substitute the biologic abatacept and reduce the steroids failed when HAM/TSP symptoms again became aggravated.

LESSONS

To the best of our knowledge, this represents the first report worldwide of a biologic aggravating HTLV-1-associated conditions. This report suggests that caution is advised when using biologics to treat HTLV-1-infected patients, though further research is required to clarify the situation.

Anti-Cyclic Citrullinated Peptide Antibody-Positive Meningoencephalitis in the Preclinical Period of Rheumatoid Arthritis

Rheumatoid meningoencephalitis (RM) is a rare complication of rheumatoid arthritis (RA). This report describes a 63-year-old man with complaints of high-grade fever, headache, and vomiting for several days before admission. Both his serum and cerebrospinal fluid were positive for anti-cyclic citrullinated peptide (CCP) antibody and rheumatoid factor, and contrast-enhanced fluid-attenuated inversion recovery magnetic resonance imaging (MRI) showed abnormal gadolinium enhancement of the meninges and high-intensity lesions in the subarachnoid spaces. The patient was diagnosed with RM despite lack of signs suggesting RA. His symptoms drastically improved with intravenous infusion of high-dose methylprednisolone. Two months later, he developed RA. The findings in this patient suggest that RM could develop prior to the onset of RA. Anti-CCP antibody and MRI findings may be useful for the diagnosis of RM, regardless of RA history.

Review of biomarkers in systemic juvenile idiopathic arthritis: helpful tools or just playing tricks?

BACKGROUND

Diagnosing systemic juvenile idiopathic arthritis (SJIA) can be extremely challenging if typical arthritis is lacking. A variety of biomarkers have been described for the diagnosis and management of SJIA. However, very few markers have been well-validated. In addition, increasing numbers of biomarkers are identified by high throughput or multi-marker panels.

METHOD

We identified diagnostic or prognostic biomarkers by systematic literature review, evaluating each according to a predefined level of verification, validation or clinical utility. Diagnostic biomarkers were those identifying SJIA versus (1) non-SJIA conditions or healthy controls (HC) or (2) other non-systemic JIA subtypes. Prognostic biomarkers were those specifically tested for the prediction of (1) disease flare, (2) increased disease activity +/- discrimination of active versus inactive disease, or (3) macrophage activation syndrome (MAS).

RESULTS

Fifty-five studies fulfilled the inclusion criteria identifying 68 unique biomarkers, of which 50/68 (74 %) were investigated by only a single research group. Candidate marker verification and clinical utility was evaluated according to whether markers were readily and reliably measurable, investigated by independent study groups, discovered by more than one method (i.e. verified markers) and validated in independent cohorts. This evaluation revealed diagnostic biomarkers of high interest for further evaluation in the diagnostic approach to SJIA that included heme oxygenase-1, interleukin-6 (IL-6), IL-12, IL-18, osteoprotegerin, S100 calcium-binding protein A12 (S100A12) and S100A8/A9.

CONCLUSION

In summary, a number of biomarkers were identified, though most had limited evidence for their use. However, our findings combined with the identified studies could inform validation studies, whether in single or multi-marker assays, which are urgently needed.

The role of cytokines in the pathogenesis of rheumatoid arthritis--Practical and potential application of cytokines as biomarkers and targets of personalized therapy

Rheumatoid arthritis (RA), as a common chronic disease leading to severe disability, requires early diagnosis and introduction of proper treatment. Deregulation in the cytokine network plays an undoubtedly crucial role in the pathogenesis of RA. The understanding of the role of cytokines in RA can be used for patients' benefit. Technological advances had already allowed introduction of the tailor-made cytokine-targeted therapies (so far anti-TNF, anti-IL-1 and anti-IL-6) into clinical practice. This type of treatment is currently developing very fast. Moreover, cytokines are considered to be potential powerful biomarkers of RA with roles predicted to grow in the future. Detailed understanding of the cytokine balance in RA may assist both the diagnostic process and therapy.

Association between arthritis score at the onset of the disease and long-term locomotor outcome in adjuvant-induced arthritis in rats

INTRODUCTION

To investigate the connection between the intensity of initial symptoms of inflammation and locomotor outcome in rheumatoid arthritis, we examined the relationship between long-term locomotor abnormalities and signs of inflammation at the onset of the disease in adjuvant-induced arthritis (AIA) in rats.

METHODS

The arthritis score and hind-paw diameter were followed from immunization to day 195 (~7 months). At this time, locomotion was recorded during forced treadmill walking using 3D motion technology before radiographic scoring of hind limb joint damage. Many locomotor parameters were analyzed including time and length parameters, limbs kinematics, lateral paw position at toe off, maximal hind-paw elevation and posture. Ankle mobility was assessed from range of motion (ROM) of the joint during locomotion. Experiments were run in AIA (n = 18) and age-matched non-AIA rats (n = 8).

RESULTS

All AIA rats exhibited signs of inflammation at day 14 with a peak of inflammatory symptoms at day 22 post-immunization. After the first episode of inflammation, 83 % of AIA rats demonstrated recurrent disease (from week 6 to week 23). The frequency of inflammatory episodes (1 to 5) was not linked to the arthritis score at day 22. At day 195 post-immunization, AIA rats showed significantly impaired locomotion and radiographic lesions as compared to control rats. Significant relationships were observed between most locomotion-related parameters and concurrent ROM of ankle, which correlated negatively with the radiographic score. ROM of ankle at day 195 correlated negatively with both the arthritis score and hind-paw diameter measured at day 14, 22 and 30 post-immunization.

CONCLUSION

Decreased ankle mobility can be considered a driver of locomotion impairment in AIA. In this model, the severity of the initial inflammatory symptoms had a good prognostic value for long-term locomotor outcome.

Existing joint erosions increase the risk of joint space narrowing independently of clinical synovitis in patients with early rheumatoid arthritis

INTRODUCTION

Clinical synovitis is often associated with damage to bone and cartilage. Previous data have suggested that joint erosions (JE) are more prevalent than joint space narrowing (JSN) and that the two processes are partly independent of each other. The objective of this study was to evaluate whether the presence of JE in an individual joint can lead to development of JSN and if existing JSN leads to new onset of JE, in the absence of synovitis.

METHODS

The Prospective Multi-Centre Randomised, Double-Blind, Active Comparator-Controlled, Parallel-Groups Study Comparing the Fully Human Monoclonal Anti-TNFα Antibody Adalimumab Given Every Second Week With Methotrexate Given Weekly and the Combination of Adalimumab and Methotrexate Administered Over 2 Years in Patients With Early Rheumatoid Arthritis (PREMIER) enrolled early rheumatoid arthritis (RA) patients who were randomized to one of three treatments: methotrexate (MTX), adalimumab (ADA), or ADA + MTX. All evaluable joints with JE and JSN measures at 26 and 52 weeks and synovitis assessments from week 26 to 52 were included. Synovitis was assessed every 2-8 weeks by swollen joint counts between weeks 26 and 52. Radiographs were taken at week 26 and 52. Two readers, blinded to time and sequence, scored 14 bilateral joints individually for JE and JSN. Multivariate logistic modeling was used to characterize the dependence of JE/JSN onset at 52 weeks. Analyses were performed based on treatment arm and were also performed within individual joints.

RESULTS

JE and swelling were independently and comparably associated with onset of JSN at week 52. Assessment by individual joints indicated that existing JE, independent of swelling, was significantly associated with JSN onset in higher proportions of metatarsophalangeal (MTP; 7/10) than proximal interphalangeal (PIP; 1/8) or metacarpophalangeal (MCP; 1/10) joints. Treatment with ADA + MTX prevents JE/JSN progression independently of its ability to suppress synovitis and limits JE/JSN onset and progression in joints with existing damage.

CONCLUSIONS

Existing JE predisposes individual joints to development of JSN independently of synovitis in the same joint. Weight-bearing MTP joints with JE may be at increased risk for JSN when compared with MCPs and PIPs.

TRIAL REGISTRATION

Clinicaltrials.gov NCT00195663. Registered 13 September 2005.

Decreased circulating visfatin is associated with improved disease activity in early rheumatoid arthritis: data from the PERAC cohort

Objective

To evaluate circulating visfatin and its relationship with disease activity and serum lipids in patients with early, treatment-naïve rheumatoid arthritis (RA).

Methods

Serum visfatin was measured in 40 patients with early RA before and after three months of treatment and in 30 age- and sex-matched healthy individuals. Disease activity was assessed using the Disease Activity Score for 28 joints (DAS28) at baseline and at three and 12 months. Multivariate linear regression analysis was performed to evaluate whether improved disease activity is related to serum visfatin or a change in visfatin level.

Results

Serum visfatin was significantly elevated in early RA patients compared to healthy controls (1.92±1.17 vs. 1.36±0.93 ng/ml; p = 0.034) and significantly decreased after three months of treatment (to 0.99±0.67 ng/ml; p<0.001). Circulating visfatin and a change in visfatin level correlated with disease activity and improved disease activity over time, respectively. A decrease in visfatin after three months predicted a DAS28 improvement after 12 months. In addition, decreased serum visfatin was not associated with an improved atherogenic index but was associated with an increase in total cholesterol level.

Conclusion

A short-term decrease in circulating visfatin may represent an independent predictor of long-term disease activity improvement in patients with early RA.

Clinical and radiological dissociation of anti-TNF plus methotrexate treatment in early rheumatoid arthritis in routine care: results from the ABRAB study

Background

Rheumatoid arthritis (RA) is a chronic autoinflammatory joint disease which leads to the destruction of joints and disability of the patients. Anti-tumour necrosis factor (anti-TNF) drugs can halt radiological progression better than conventional DMARDs even in clinical non-responders.

Methods

The efficacy of anti-TNF plus methotrexate (MTX) treatment versus MTX monotherapy on clinical and radiological outcomes were compared in early rheumatoid arthritis (RA) patients in clinical practice by retrospective analysis of an observational cohort.

49 early RA patients (group A) on first-line MTX monotherapy and 35 early RA patients (group B) on anti-TNF plus MTX treatment were selected from an observational cohort and evaluated retrospectively focusing on their first twelve months of treatment. Data on disease activity (DAS28) and functional status (HAQ-DI) were collected three monthly. One-yearly radiological progression was calculated according to the van der Heijde modified Sharp method (vdHS). Clinical non-responder patients in both groups were selectively investigated from a radiological point of view.

Results

Disease activity was decreased and functional status was improved significantly in both groups. One-yearly radiological progression was significantly lower in group B than in group A. The percentage of patients showing radiological non-progression or rapid radiological progression demonstrated a significant advantage for group B patients. In addition non-responder patients in group B showed similar radiological results as responders, while a similar phenomenon was not observed in patients in group A.

Conclusions

Clinical efficacy within our study was similar for tight-controlled MTX monotherapy as well as for combination treatment with anti-TNF and MTX. However MTX monotherapy was accompanied by more rapid radiological progression and less radiological non-progression. Anti-TNF plus MTX decreased radiological progression even in clinical non-responders supporting the advantage of anti-TNF plus MTX combination in dissociating clinical and radiological effects.

Effects of laser treatment on the expression of cytosolic proteins in the synovium of patients with osteoarthritis

BACKGROUND AND OBJECTIVE

Low level laser therapy (LLLT) has been developed for non-invasive treatment of joint diseases. We have previously shown that LLLT influenced synovial protein expression in rheumatoid arthritis (RA). The aim of this study was to assess the effects of laser irradiation on osteoarthritic (OA) synovial protein expression.

STUDY DESIGN/MATERIALS AND METHODS

The synovial membrane samples removed from the knees of 6 OA patients were irradiated ex vivo using near infrared diode laser (807-811 nm; 25 J/cm(2) ). An untreated sample taken from the same patient served as control. Synovial protein separation and identification were performed by two-dimensional differential gel electrophoresis and mass spectrometry, respectively.

RESULTS

Eleven proteins showing altered expression due to laser irradiation were identified. There were three patients whose tissue samples demonstrated a significant increase (P < 0.05) in mitochondrial heat shock 60 kD protein 1 variant 1. The expression of the other proteins (calpain small subunit 1, tubulin alpha-1C and beta 2, vimentin variant 3, annexin A1, annexin A5, cofilin 1, transgelin, and collagen type VI alpha 2 chain precursor) significantly decreased (P < 0.05) compared to the control samples.

CONCLUSIONS

A single diode laser irradiation of the synovial samples of patients with osteoarthritis can statistically significantly alter the expression of some proteins in vitro. These findings provide some more evidence for biological efficacy of LLLT treatment, used for osteoarthritis.

Protein Quantification by MRM for Biomarker Validation

In this chapter we describe how mass spectrometry-based quantitative protein measurements by multiple reaction monitoring (MRM) have opened up the opportunity for the assembly of large panels of candidate protein biomarkers that can be simultaneously validated in large clinical cohorts to identify diagnostic protein biomarker signatures. We outline a workflow in which candidate protein biomarker panels are initially assembled from multiple diverse sources of discovery data, including proteomics and transcriptomics experiments, as well as from candidates found in the literature. Subsequently, the individual candidates in these large panels may be prioritised by application of a range of bioinformatics tools to generate a refined panel for which MRM assays may be developed. We describe a process for MRM assay design and implementation, and illustrate how the data generated from these multiplexed MRM measurements of prioritised candidates may be subjected to a range of statistical tools to create robust biomarker signatures for further clinical validation in large patient sample cohorts. Through this overall approach MRM has the potential to not only support individual biomarker validation but also facilitate the development of clinically useful protein biomarker signatures.

Serum levels of vasoactive intestinal peptide as a prognostic marker in early arthritis

Objective

Suitable biomarkers are essential for the design of therapeutic strategies in personalized medicine. Vasoactive intestinal peptide (VIP) has demonstrated immunomodulatory properties in autoimmune murine and ex vivo human models. Our aim was to study serum levels of VIP during the follow-up of an early arthritis (EA) cohort and to analyze its value as a biomarker predicting severity and therapeutic requirements.

Methods

Data from 91 patients on an EA register were analyzed (76% rheumatoid arthritis (RA), 24% undifferentiated arthritis, 73% women, and median age 54 years; median disease duration at entry, 5.4 months). We collected per protocol sociodemographic, clinical, and therapeutic data. VIP levels were determined by enzyme immunoassay in sera harvested from the 91 patients (353 visits; 3.9 visit/patient) and from 100 healthy controls. VIP values below the 25^th percentile of those assessed in healthy population were considered low. To determine the effect of independent variables on VIP levels, we performed a longitudinal multivariate analysis nested by patient and visit. A multivariate ordered logistic regression was modeled to determine the effect of low VIP serum levels on disease activity at the end of follow-up.

Results

VIP concentrations varied considerably across EA patients. Those fulfilling the criteria for RA had the lowest values in the whole sample, although no significant differences were observed compared with healthy donors. Disease activity, which was assessed using DAS28, inversely correlated with VIP levels. After a two-year follow-up, those patients with low baseline levels of VIP displayed higher disease activity and received more intensive treatment.

Conclusion

Patients who are unable to up-regulate VIP seem to have a worse clinical course despite receiving more intense treatment. Therefore, measurement of VIP levels may be suitable as a prognostic biomarker.

Antroquinonol mitigates an accelerated and progressive IgA nephropathy model in mice by activating the Nrf2 pathway and inhibiting T cells and NLRP3 inflammasome

High levels of reactive oxygen species (ROS), systemic T cell activation, and macrophage infiltration in the kidney are implicated in the acceleration and progression of IgA nephropathy (IgAN), the most frequent type of primary glomerulonephritis. However, the pathogenic mechanism of IgAN is still little understood, and it remains a challenge to establish a specific therapeutic strategy for this type of glomerular disorder. Recently, we showed that antroquinonol (Antroq), a pure active compound from Antrodia camphorata mycelium, inhibits renal inflammation and reduces oxidative stress in a mouse model of renal fibrosis. But the anti-inflammatory and immune-regulatory effects of Antroq on the acceleration and progression of primary glomerular disorders have not been determined. In this study, we show that Antroq administration substantially impeded the development of severe renal lesions, such as intense glomerular proliferation, crescents, sclerosis, and periglomerular interstitial inflammation, in mice with induced accelerated and progressive IgAN (AcP-IgAN). Further mechanistic analysis in AcP-IgAN mice showed that, early in the developmental stage of the AcP-IgAN model, Antroq promoted the Nrf2 antioxidant pathway and inhibited the activation of T cells and NLRP3 inflammasome. Significantly improved proteinuria/renal function and histopathology in AcP-IgAN mice of an established stage supported potential therapeutic effects of Antroq on the disease. In addition, Antroq was shown to inhibit activation of NLRP3 inflammasome in vitro by an IgA immune complex (IC) partly involving a reduced ROS production in IgA-IC-primed macrophages, and this finding may be helpful in the understanding of the mode of action of Antroq in the treated AcP-IgAN mice.

Association of joint space narrowing with impairment of physical function and work ability in patients with early rheumatoid arthritis: protection beyond disease control by adalimumab plus methotrexate

OBJECTIVES

Tumour necrosis factor inhibition plus methotrexate is believed to inhibit radiographic progression independent of inflammation. This analysis assessed whether these protective effects are exerted on bone (joint erosion; JE) and/or cartilage (joint space narrowing; JSN), and what the independent effects of JE/JSN progression are on longer-term patient-reported outcomes.

METHODS

PREMIER was a 2-year, randomised, controlled trial of adalimumab plus methotrexate (ADA+MTX) versus the monotherapies. The impact of treatment on the relationships between time-averaged disease activity (TA-DAS28(CRP)) and changes in JE/JSN and associations of JE/JSN with the disability index of the health assessment questionnaire (HAQ-DI) at baseline and weeks 52 and 104 were assessed through non-parametric approaches of analysis of variance and quantile regression. JE/JSN association with employment status was evaluated at baseline and weeks 52 and 104 through logistic regression.

RESULTS

Increasing tertiles of TA-DAS28(CRP) were associated with JE and JSN progression in the monotherapy groups, a phenomenon largely absent in ADA+MTX-treated patients. Although JSN was not associated with HAQ-DI at baseline, it was at 52 and 104 weeks. In contrast, JE was not associated with HAQ-DI at any time point examined. Odds of being employed at baseline, 52 weeks and 104 weeks were significantly associated with lower JSN, but not JE, scores.

CONCLUSIONS

ADA+MTX inhibited both JE and JSN progression independently of disease activity. JSN played a more prominent role in patient-reported outcomes than JE. Preventing the onset or worsening of JSN probably represents a critical aspect of effective disease management of early rheumatoid arthritis patients.

Tumor necrosis factor-inhibiting therapy preferentially targets bone destruction but not synovial inflammation in a tumor necrosis factor-driven model of rheumatoid arthritis

OBJECTIVE

To investigate how tumor necrosis factor (TNF)-inhibiting therapy affects bone destruction and inflammation in a TNF-driven mouse model of rheumatoid arthritis.

METHODS

In order to evaluate the influence of TNF on osteoclastogenesis in vitro, different concentrations of TNF were added to spleen cell-derived monocytes in the absence or presence of different concentrations of RANKL. In addition, the effects of TNF inhibition on osteoclast precursors as well as local bone destruction in vivo were assessed by treating TNF-transgenic mice with different doses of adalimumab.

RESULTS

TNF stimulated osteoclastogenesis mainly by increasing the number of osteoclast precursor cells in vitro. This TNF effect was independent of the presence of RANKL. In the hTNF-transgenic mouse model of destructive arthritis, low-dose TNF-inhibiting therapy with adalimumab had no effect on synovial inflammation but significantly inhibited local bone destruction and the generation of osteoclasts. This inhibition was accompanied by a reduction in the number of c-Fms-positive osteoclast precursor cells in the bone marrow and a reduction of the osteoclast precursor pools in the blood and inflamed synovial membrane of hTNF-transgenic mice.

CONCLUSION

Low-dose TNF-inhibiting therapy significantly reduces bone erosions by reducing the number of circulating and joint-invading osteoclast precursors. This effect is uncoupled from its antiinflammatory action.

Periarticular bone gain at proximal interphalangeal joints and changes in bone turnover markers in response to tumor necrosis factor inhibitors in rheumatoid and psoriatic arthritis

OBJECTIVE

Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) are characterized by periarticular bone erosion; periarticular bone formation is a feature in PsA. The effect of anti-tumor necrosis factor-α (TNF-α) on periarticular bone remodeling is unclear in both diseases. Our aim was to assess the response of bone turnover markers (BTM) and hand bone mineral density (BMD) to anti-TNF over 3 years in RA and PsA.

METHODS

We measured serum bone-specific alkaline phosphatase (bone ALP), procollagen type-I N-propeptide (PINP), intact osteocalcin, C-terminal cross-linking telopeptides (CTX-I), urinary N-terminal cross-linking telopeptide of type-I collagen (NTX-I), and free deoxypyridinoline crosslinks (fDPD) at baseline, 1, 12, and 36 months. BMD measurements (hands/spine/hip) were obtained at 3 timepoints.

RESULTS

We recruited 62 patients (RA 35; PsA 27). BTM correlated significantly with hand BMD but not with central BMD. Low hand BMD was associated with RA and increased BTM. Following anti-TNF therapy, hip BMD declined while spine and hand BMD were unchanged. Periarticular BMD at proximal interphalangeal (PIP) joints increased while it decreased at metacarpophalangeal joints. Bone ALP increased steadily and was always higher in PsA. PINP and intact osteocalcin increased to a lesser extent, but resorption markers did not change.

CONCLUSION

At baseline, hand BMD was inversely associated with BTM. Bone formation rather than resorption markers better showed the bone response to anti-TNF. Despite a lack of effect on central BMD, the modest effect of anti-TNF on PIP BMD may provide evidence that BTM reflect specifically bone remodeling activity at periarticular sites of inflammation in RA and PsA.

A multi-biomarker score measures rheumatoid arthritis disease activity in the BeSt study

Objective. To evaluate a multi-biomarker disease activity (MBDA) score, a novel index based on 12 serum proteins, as a tool to guide management of RA patients.

Methods. A total of 125 patients with RA from the Behandel Strategieën study were studied. Clinical data and serum samples were available from 179 visits, 91 at baseline and 88 at year 1. In each serum sample, 12 biomarkers were measured by quantitative multiplex immunoassays and the concentrations were used as input to a pre-specified algorithm to calculate MBDA scores.

Results. MBDA scores had significant correlation with DAS28-ESR (Spearman’s ρ = 0.66, P < 0.0001) and also correlated with simplified disease activity index, clinical disease activity index and HAQ Disability Index (all P < 0.0001). Changes in MBDA between baseline and year 1 were also correlated with changes in DAS28-ESR (ρ = 0.55, P < 0.0001). Groups stratified by European League Against Rheumatism disease activity (DAS28-ESR ≤ 3.2, 3.2–5.1 and > 5.1) had significantly different MBDA scores (P < 0.0001) and MBDA score could discriminate ACR/EULAR Boolean remission with an area under the receiver operating characteristic curve of 0.83 (P < 0.0001).

Conclusion: The MBDA score reflects current clinical disease activity and can track changes in disease activity over time.

My treatment approach to rheumatoid arthritis

The past decade has brought important advances in the understanding of rheumatoid arthritis and its management and treatment. New classification criteria for rheumatoid arthritis, better definitions of treatment outcome and remission, and the introduction of biologic response-modifying drugs designed to inhibit the inflammatory process have greatly altered the approach to managing this disease. More aggressive management of rheumatoid arthritis early after diagnosis and throughout the course of the disease has resulted in improvement in patient functioning and quality of life, reduction in comorbid conditions, and enhanced survival.

Rheumatoid arthritis. Evidence for a genetic component to disease severity in RA

Rheumatoid arthritis (RA) is partly heritable; genetic and serological markers are known to confer risk of developing pathology. But given clinical heterogeneity in RA, can we predict who will develop severe disease? Substantial heritability of erosive progression rates has now been identified, but better prognostic biomarkers remain wanting.

Timing and Magnitude of Initial Change in Disease Activity Score 28 Predicts the Likelihood of Achieving Low Disease Activity at 1 Year in Rheumatoid Arthritis Patients Treated with Certolizumab Pegol: A Post-hoc Analysis of the RAPID 1 Trial

Objective.

To determine the relationship between timing and magnitude of Disease Activity Score [DAS28(ESR)] nonresponse (DAS28 improvement thresholds not reached) during the first 12 weeks of treatment with certolizumab pegol (CZP) plus methotrexate, and the likelihood of achieving low disease activity (LDA) at 1 year in patients with rheumatoid arthritis.

Methods.

In a post-hoc analysis of the RAPID 1 study, patients achieving LDA [DAS28(ESR) ≤ 3.2] at Year 1 were assessed according to DAS28 nonresponse at various timepoints within the first 12 weeks.

Results.

Seven-hundred eighty-three patients were included (CZP 200 mg, n = 393; CZP 400 mg, n = 390). A total of 86.9% of patients in the CZP 200 mg group had a DAS28 improvement of ≥ 1.2 by Week 12. Of the 13.1% of patients with DAS28 improvement < 1.2 by Week 12, only 2.0% had LDA at Year 1. Failure to achieve LDA at Year 1 depended on timing of nonresponse — 22.3%, 8.4%, and 2.0% of patients with DAS28 improvement < 1.2 by Weeks 1, 6, and 12, respectively, had LDA at Year 1 — and magnitude of initial lack of DAS28 improvement; for example, compared with the patients with DAS28 < 1.2 improvement, fewer patients with DAS28 < 0.6 had LDA at Year 1 (17.4%, 2.4%, and 0.0% at Weeks 1, 6, and 12, respectively).

Conclusion.

Failure to achieve improvement in DAS28 within the first 12 weeks of therapy was predictive of a low probability of achieving LDA at Year 1. Moreover, the accuracy of the prediction was found to be strongly dependent on the magnitude and timing of the lack of the response. (Clinical Trial Registration Nos. NCT00152386 and NCT00175877).

Long-term stability of anti-cyclic citrullinated peptide antibody status in patients with early inflammatory polyarthritis

Introduction

The utility of reassessing anti-cyclic citrullinated peptide (anti-CCP) antibody status later in disease in patients presenting with early undifferentiated inflammatory polyarthritis, particularly in those who test negative for both anti-CCP and rheumatoid factor (RF) at baseline, remains unclear. We aimed therefore to determine the stability of CCP antibody status over time and the prognostic utility of repeated testing in subjects with early inflammatory polyarthritis (IP).

Methods

Anti-CCP and RF were measured at baseline and 5 years in 640 IP patients from the Norfolk Arthritis Register, a primary care-based inception cohort. The relation between change in anti-CCP status/titer and the presence of radiologic erosions, the extent of the Larsen score, and Health Assessment Questionnaire (HAQ) score by 5 years was investigated.

Results

With a cut-off of 5 U/ml, 28% subjects tested positive for anti-CCP antibodies, 29% for RF, and 21% for both at baseline. Nine (2%) anti-CCP-negative patients seroconverted to positive, and nine (4.6%) anti-CCP-positive individuals became negative between baseline and 5 years. In contrast, RF status changed in 17% of subjects. However, change in RF status was strongly linked to baseline anti-CCP status and was not independently associated with outcome. Ever positivity for anti-CCP antibodies by 5 years did not improve prediction of radiographic damage compared with baseline status alone (accuracy, 75% versus 74%). A higher baseline anti-CCP titer (but not change in anti-CCP titer) predicted worse radiologic damage at 5 years (P < 0.0001), even at levels below the cut-off for anti-CCP positivity. Thus, a titer of 2 to 5 U/ml was strongly associated with erosions by 5 years (odds ratio, 3.6 (1.5 to 8.3); P = 0.003).

Conclusions

Repeated testing of anti-CCP antibodies or RF in patients with IP does not improve prognostic value and should not be recommended in routine clinical practice.

The pathogenesis of rheumatoid arthritis: new insights from old clinical data?

Despite their different targets, biologic agents used for blockade of TNF and IL-6, inhibition of T-cell co-stimulation and B-cell depletion all have similar beneficial effects on the outcome of rheumatoid arthritis (RA). This observation raises questions as to whether the targets of these therapies might all be involved in a common pathogenetic pathway. However, blockade of TNF and IL-6 has a similar inhibitory effect on joint damage progression in patients with either early or late disease. In comparison, B-cell depletion and inhibition of T-cell co-stimulation seem to have a somewhat delayed effect on joint damage (compared with cytokine inhibition), which suggests that these approaches affect upstream pathogenetic events. This article discusses these disparities and presents hypotheses as to whether clinical trial data can be used to determine at which point a biologic agent might interfere with the pathogenetic cascade in RA.

Inflammatory bone loss: pathogenesis and therapeutic intervention

Bone is a tissue undergoing continuous building and degradation. This remodelling is a tightly regulated process that can be disturbed by many factors, particularly hormonal changes. Chronic inflammation can also perturb bone metabolism and promote increased bone loss. Inflammatory diseases can arise all over the body, including in the musculoskeletal system (for example, rheumatoid arthritis), the intestine (for example, inflammatory bowel disease), the oral cavity (for example, periodontitis) and the lung (for example, cystic fibrosis). Wherever inflammatory diseases occur, systemic effects on bone will ensue, as well as increased fracture risk. Here, we discuss the cellular and signalling pathways underlying, and strategies for therapeutically interfering with, the inflammatory loss of bone.

Novel regulatory mechanisms in inflammatory arthritis: a role for microRNA

Elucidating pathways that regulate cytokine production in the context of autoimmune disease will likely lead to the development of novel therapeutics. Herein, we review data suggesting that microRNAs (miRs) represent one such level of regulatory activity, with particular emphasis on the pathogenesis of rheumatoid arthritis (RA). A series of miRs have been identified to be dysregulated in cell subsets within the articular compartment of patients with RA. These have a critical role in regulating cartilage-invading phenotype of RA synovial fibroblasts. More recently, several studies suggest that miRs also regulate leukocyte activation and cytokine production that in turn contribute to the immunologic component of effector synovial pathology. Together, these observations open an exciting new vista of understanding and therapeutic opportunity for this difficult and common disease.

Interleukin 15 levels in serum may predict a severe disease course in patients with early arthritis

Background

Interleukin-15 (IL-15) is thought to be involved in the physiopathological mechanisms of RA and it can be detected in the serum and the synovial fluid of inflamed joints in patients with RA but not in patients with osteoarthritis or other inflammatory joint diseases. Therefore, the objective of this work is to analyse whether serum IL-15 (sIL-15) levels serve as a biomarker of disease severity in patients with early arthritis (EA).

Methodology and Results

Data from 190 patients in an EA register were analysed (77.2% female; median age 53 years; 6-month median disease duration at entry). Clinical and treatment information was recorded systematically, especially the prescription of disease modifying anti-rheumatic drugs. Two multivariate longitudinal analyses were performed with different dependent variables: 1) DAS28 and 2) a variable reflecting intensive treatment. Both included sIL-15 as predictive variable and other variables associated with disease severity, including rheumatoid factor (RF) and anti-cyclic citrullinated peptide antibodies (ACPA). Of the 171 patients (638 visits analysed) completing the follow-up, 71% suffered rheumatoid arthritis and 29% were considered as undifferentiated arthritis. Elevated sIL-15 was detected in 29% of this population and this biomarker did not overlap extensively with RF or ACPA. High sIL-15 levels (β Coefficient [95% confidence interval]: 0.12 [0.06–0.18]; p<0.001) or ACPA (0.34 [0.01–0.67]; p = 0.044) were significantly and independently associated with a higher DAS28 during follow-up, after adjusting for confounding variables such as gender, age and treatment. In addition, those patients with elevated sIL-15 had a significantly higher risk of receiving intensive treatment (RR 1.78, 95% confidence interval 1.18–2.7; p = 0.007).

Conclusions

Patients with EA displaying high baseline sIL-15 suffered a more severe disease and received more intensive treatment. Thus, sIL-15 may be a biomarker for patients that are candidates for early and more intensive treatment.

Tocilizumab inhibits progression of joint damage in rheumatoid arthritis irrespective of its anti-inflammatory effects: disassociation of the link between inflammation and destruction

Background

Treatment with tumour necrosis factor inhibitors (TNF-i) plus methotrexate (MTX), but not MTX monotherapy alone, inhibits joint damage progression even at higher levels of disease activity. Such disassociation of disease activity and structural damage has not been shown for biological agents other than TNF-i.

Objectives

To evaluate whether interleukin 6 (IL-6) inhibition with tocilizumab (TCZ) interferes with joint destruction beyond its effects on disease activity.

Methods

A random 90% sample of data from the (The Tocilizumab Safety and the Prevention of Structural Joint Damage Study) LITHEtrial on active rheumatoid arthritis (RA) despite MTX was used, which compared addition of placebo (n=117) with addition of TCZ (n=414) every 4 weeks. Baseline and 1-year values of clinical and serological variables were correlated with changes to 1 year of the total Genant-modified Sharp score (TGSS) using a Spearman test, and the progression of TGSS, erosion and joint space narrowing (JSN) scores in groups with low and high disease activity were compared for placebo and TCZ (Kruskal–Wallis).

Results

Baseline variables were similar among the groups. Change of TGSS was lower in patients receiving TCZ than placebo (TCZ: 0.29±0.96; placebo: 0.90±1.92; p=0.0007). In patients receiving placebo, the correlation with TGSS change was significant for baseline scores of the simplified disease activity index (SDAI; r=0.18, p=0.047) and swollen joint count 28 (r=0.22, p=0.019), with similar trends for C-reactive protein. Similar correlations were seen for SDAI, clinical disease activity index, disease activity score 28 at 1 year with x-ray change during that year (r=0.26–0.28, p=0.002–0.006). In contrast, none of the baseline or 1-year variables showed significant correlation with x-ray changes in patients receiving TCZ+MTX, suggesting a disassociation of the link between disease activity and damage by TCZ. Finally, for patients in remission or with low disease activity, progression of TGSS, erosion and JSN was similar among treatment groups (TGSS: placebo, 0.4±1.1; TCZ, 0.2±0.7; p=NS), while for patients with moderate or high disease activity placebo-treated patients progression was significantly greater (TGSS: 1.2±2.2 vs 0.4±1.2; p=0.0009).

Conclusions

IL-6 inhibition with TCZ plus MTX retards joint damage progression independently of its impact on disease activity. Similar effects have hitherto been reported only for TNF-i. This indicates that the effects of IL-6 inhibition on progression of joint damage in RA are among the most profound currently attainable.

Decreases in serum levels of S100A8/9 (calprotectin) correlate with improvements in total swollen joint count in patients with recent-onset rheumatoid arthritis

INTRODUCTION

The aim of this study was to examine the serum levels of S100 proteins and to evaluate their role in patients with recent-onset rheumatoid arthritis (RA).

METHODS

Serum levels of S100A8/9 and S100A12 were analysed in 43 patients with recent-onset RA, both before and three months after the initiation of conventional treatment, as well as in 32 healthy individuals. Disease activity was assessed based on serum levels of C-reactive protein (CRP), the Disease Activity Score for 28 joints (DAS28) and the total number of swollen joints count for 66 joints (SJC).

RESULTS

The levels of serum S100A8/9 and S100A12 were significantly higher in patients with recent-onset RA compared to the levels in healthy individuals (P < 0.0001) and normalised after three months of treatment. Using age- and sex-adjusted analysis, S100A8/9 levels were correlated with CRP (r = 0.439, P < 0.01), DAS28 (r = 0.501, P = 0.002) and SJC (r = 0.443, P = 0.007), while S100A12 was less significantly correlated with these parameters. Higher levels of S100A8/9 at baseline predicted improvement in the levels of CRP and SJC over time. Moreover, decreases in serum S100A8/9 were associated with decreased serum levels of CRP (r = 0.459, P = 0.005) and improvements in SJC (r = 0.459, P = 0.005). In multiple linear regression analyses, decreases in S100A8/9 but not CRP were significant predictors for improvements in SJC (P = 0.001).

CONCLUSIONS

This study is the first to show normalisation of elevated S100 proteins in patients with recent-onset RA after the initiation of conventional treatment. Therefore, S100A8/9 might potentially be a predictive marker for improvement in the total number of swollen joints in patients in the early phase of RA.

Recommendations for an update of 2003 European regulatory requirements for registration of drugs to be used in the treatment of RA

Since 2003, the European Medicines Agency (EMA) document, 'Points to consider on clinical investigation of medicinal products other than NSAIDs (nonsteroidal anti-inflammatory drugs) for the treatment of rheumatoid arthritis' has provided guidance for the clinical development of both biologic and non-biologic disease-modifying antirheumatic drugs (DMARDs). In the last few years, several new products have been developed or are in development for the treatment of RA, which offer significant efficacy with regard to disease control, including prevention of structural damage and disability. Concurrently, novel insights have been gained with respect to the assessment of disease activity, joint damage and disability. New treatment strategies have been established which relate to early therapy, tight control and rapid switching of medication. Accordingly, several new EULAR/ACR recommendations have been or are being developed. Several important additions and changes are needed in the 2003 guidance to incorporate the current scientific knowledge into clinical trial design for the development of future products. Under the auspices of the Group for the Respect of Ethics and Excellence in Science (GREES), a group of experts in the field of RA and clinical trial design met to provide a consensus recommendation for an update to the 2003 EMA guidance document.

Validity of clinical associations of biomarkers in translational research studies: the case of systemic autoimmune diseases

Introduction

Validity of biomarkers may be affected if studies do not include certain features in their design. We evaluated whether translational research studies of potential biomarkers incorporated design features important for valid clinical associations.

Methods

We searched 10 journals for translational studies in six systemic autoimmune diseases published in 2004 through 2009. We included studies that reported associations between laboratory markers and the presence of disease, measures of disease activity, or prognosis. We examined the following design features: age, sex, and race matching; control for effects of treatment on expression of the biomarker; inclusion of patients with both early and late disease, or both active and inactive disease; longitudinal or cross-sectional design; and use of validated activity and damage measures.

Results

Among 170 articles, 156 articles examined potential biomarkers for diagnosis, 37 for disease activity assessment, and nine for prognosis; 67 were studies of rheumatoid arthritis (RA); 48, of systemic lupus erythematosus; and 41, of other diseases. Gene-expression profiles were the most commonly examined potential biomarkers (n = 51). Fewer than one half of studies incorporated study-design features important for valid clinical associations. Only 47.4% of studies of biomarkers for diagnosis had groups that were age-matched, 45.5% were sex-matched, and 35.3% controlled for treatment. Studies that examined biomarkers in histologic samples and studies of RA were less likely to include important design features.

Conclusions

Fewer than one half of translational studies of potential biomarkers incorporated design features needed for valid interpretation of clinical associations. Attention to these features could reduce false-positive and false-negative associations.

Analysis of complex biomarkers for human immune-mediated disorders based on cytokine responsiveness of peripheral blood cells

The advent of improved biomarkers promises to enhance the clinical care for patients with rheumatoid arthritis (RA) and other immune-mediated disorders. We have developed an innovative approach to broadly assess the cytokine responsiveness of human PBMCs using a multistimulant panel and multiplexed immunoassays. The objective of this study was to demonstrate this concept by determining whether cytokine profiles could discriminate RA patients according to disease stage (early versus late) or severity. A 10-cytokine profile, consisting of IL-12, CCL4, TNF-alpha, IL-4, and IL-10 release in response to stimulation with anti-CD3/anti-CD28, CXCL8 and IL-6 in response to CMV and EBV lysate, and IL-17A, GM-CSF, and CCL2 in response to human heat shock protein 60, easily discriminated the early RA group from controls. These data were used to create an immune response score, which performed well in distinguishing the early RA patients from controls and also correlated with several markers of disease severity among the patients with late RA. In contrast, the same 10-cytokine profile assessed in serum was far less effective in discriminating the groups. Thus, our approach lays the foundation for the development of immunologic "signatures" that could be useful in predicting disease course and monitoring the outcomes of therapy among patients with immune-mediated diseases.

Rapid and sustained improvement in bone and cartilage turnover markers with the anti-interleukin-6 receptor inhibitor tocilizumab plus methotrexate in rheumatoid arthritis patients with an inadequate response to methotrexate: results from a substudy of the multicenter double-blind, placebo-controlled trial of tocilizumab in inadequate responders to methotrexate alone

OBJECTIVE

To investigate the effects of tocilizumab (TCZ) added to a stable dosage of methotrexate (MTX) on biochemical markers of bone and cartilage metabolism in patients in the multicenter double-blind, placebo-controlled OPTION (Tocilizumab Pivotal Trial in Methotrexate Inadequate Responders) study who have moderate-to-severe rheumatoid arthritis (RA) and an inadequate response to MTX.

METHODS

Included in this study were 416 of the 623 patients with active RA enrolled in the OPTION study. Patients were randomized to receive TCZ (4 mg/kg or 8 mg/kg) or placebo intravenously every 4 weeks, with MTX continued at the stable prestudy doses (10-25 mg for 20 weeks, with a final followup at week 24). Serum biochemical markers of bone formation (osteocalcin, N-terminal propeptide of type I collagen [PINP]), bone resorption (C-terminal crosslinking telopeptide of type I collagen [CTX-I] and C-terminal crosslinking telopeptide of type I collagen generated by matrix metalloproteinases [ICTP]), cartilage metabolism (N-terminal propeptide of type IIA collagen [PIIANP]), collagen helical peptide [HELIX-II]), and matrix metalloproteinase 3 (MMP-3) were measured at baseline and at weeks 4, 16, and 24.

RESULTS

TCZ induced marked dose-dependent reductions in PIIANP, HELIX-II, and MMP-3 levels at week 4 that were maintained until week 24, an effect associated with increased levels of bone formation markers that were significant as compared with placebo only for PINP and only at 4 weeks (P < 0.01 for both TCZ doses). TCZ induced significant decreases in the bone degradation markers CTX-I and ICTP, providing initial evidence of a beneficial effect on bone turnover. TCZ-treated patients who met the American College of Rheumatology 50% improvement criteria (achieved an ACR50 response) or achieved clinical remission (as determined by a Disease Activity Score in 28 joints <2.6) at week 24 had greater reductions in ICTP, HELIX-II, and MMP-3 levels as compared with ACR50 nonresponders.

CONCLUSION

TCZ combined with MTX reduces systemic bone resorption, cartilage turnover, and proteolytic enzyme MMP-3 levels, which provides evidence of a limitation of joint damage and possible beneficial effects on skeletal structure in patients with established moderate-to-severe RA.

The role of biomarkers in the management of patients with rheumatoid arthritis

In recent years, patient outcomes have improved dramatically with the availability of effective treatments for the management of rheumatoid arthritis (RA). RA, however, is a heterogeneous disease with variable disease progression and treatment response. Whereas some patients respond to a single disease-modifying antirheumatic drug, others require more intensive treatment strategies. Assessing disease severity at diagnosis and monitoring disease activity on an individual level would be a more accurate way of tailoring therapy, ensuring optimal treatment for those at greatest risk of disease progression, long-term disability, and joint damage without unnecessary overtreatment. Assessment of disease activity and severity is currently based on a combination of clinical and laboratory parameters that aid treatment decisions. Use of biomarkers may provide a more accurate means of objectively assessing the disease. This article reviews the role of biomarkers in the management of RA.