Outcome measures in inflammatory rheumatic diseases

Inflammatory rheumatic diseases are generally multifaceted disorders and, therefore, measurement of multiple outcomes is relevant to most of these diseases. Developments in outcome measures in the rheumatic diseases are promoted by the development of successful treatments. Outcome measurement will increasingly deal with measurement of low levels of disease activity and avoidance of disease consequences. It is an advantage for patient management and knowledge transfer if the same outcomes are used in practice and in trials. Continuous measures of change are generally the most powerful and, therefore, are preferred as primary outcomes in trials. For daily clinical practice, outcome measures should reflect the patients' state and have to be easily derivable. The objective of this review is to describe recent developments in outcome measures for inflammatory rheumatic diseases for trials and clinical practice, with an emphasis on rheumatoid arthritis.     

A randomized, controlled trial of interferon-beta-1a (Avonex(R)) in patients with rheumatoid arthritis: a pilot study [ISRCTN03626626

The objective of this study was to evaluate the safety and possible efficacy of IFN-beta-1a for the treatment of patients with rheumatoid arthritis (RA). Twenty-two patients with active RA were enrolled in a phase II randomized, double-blind, placebo-controlled trial of 30 microg IFN-beta-1a by weekly self-injection for 24 weeks. The primary outcome of the study was safety. Secondary outcomes included the proportion of patients achieving an American College of Rheumatology (ACR) 20 response at 24 weeks. There were no significant differences in adverse events reported in the two groups. Fewer than 20% of patients in each arm of the study achieved an ACR 20 response at 24 weeks (P = 0.71). Sixty-nine percent of patients receiving IFN-beta and 67% receiving placebo terminated the study early, most of them secondary to a perceived lack of efficacy. Overall, IFN-beta-1a had a safety profile similar to that of placebo. There were no significant differences in the proportion of patients achieving an ACR 20 response between the two groups.     

A randomized,controlled trial of interferon-β-1a (Avonex<Superscript>®</Superscript>) in patients with rheumatoid arthritis: a pilot study [ISRCTN03626626]

The objective of this study was to evaluate the safety and possible efficacy of IFN-β-1a for the treatment of patients with rheumatoid arthritis (RA). Twenty-two patients with active RA were enrolled in a phase II randomized, double-blind, placebo-controlled trial of 30 μg IFN-β-1a by weekly self-injection for 24 weeks. The primary outcome of the study was safety. Secondary outcomes included the proportion of patients achieving an American College of Rheumatology (ACR) 20 response at 24 weeks. There were no significant differences in adverse events reported in the two groups. Fewer than 20% of patients in each arm of the study achieved an ACR 20 response at 24 weeks (P = 0.71). Sixty-nine percent of patients receiving IFN-β and 67% receiving placebo terminated the study early, most of them secondary to a perceived lack of efficacy. Overall, IFN-β-1a had a safety profile similar to that of placebo. There were no significant differences in the proportion of patients achieving an ACR 20 response between the two groups.     

Validation of ACR/EULAR definition of remission in rheumatoid arthritis from RA practice: the ESPOIR cohort

Introduction

In development of the American College of Rheumatology (ACR)/European League Against Rheumatism (EULAR) rheumatoid arthritis (RA) remission definitions using clinical trials data, one criterion used to compare different remission definitions was whether, compared with those not in remission, those in remission had evidence of later disease stability defined by x-ray and functional status. Validation of the RA remission criteria using observational study data is necessary before recommending their use in practice.

Methods

Using data from those who met RA criteria in the ESPOIR cohort, we matched each person in remission with a person not in remission and then carried out analyses comparing later stability of x-ray and health assessment questionnaire (HAQ) between the two groups. We compared the predictive validity of the same candidate definitions of remission evaluated in the ACR/EULAR process. To minimize potential bias and produce more stable results, we used a bootstrap resampling approach to select those not in remission, repeating the sample matching analysis process 500 times.

Results

Results were similar to those of clinical trials analyzed for the ACR/EULAR remission criteria. Specifically, the ACR/EULAR remission definitions using either an simple disease activity index (SDAI) ≤ 3.3, clinical disease activity index (CDAI) ≤ 2.8 or a definition of remission requiring tender joint count, swollen joint count, patient global assessment all ≤ 1 performed as well or better than other candidate definitions of remission in terms of predicting later x-ray and function stability.

Conclusions

ACR/EULAR definitions of remission developed for trials are similarly valid in observational studies in RA and could be used in practice.     

Pain persists in DAS28 rheumatoid arthritis remission but not in ACR/EULAR remission: a longitudinal observational study

Introduction  

Disease remission has become a feasible goal for most rheumatoid arthritis (RA) patients; however, patient-reported symptoms, such as pain, may persist despite remission. We assessed the prevalence of pain in RA patients in remission according to the Disease Activity Score (DAS28-CRP4) and the American College of Rheumatology/European League Against Rheumatism (ACR/EULAR) remission criteria.     

Most Trial Eligibility Criteria and Patient Baseline Characteristics Do Not Modify Treatment Effect in Trials Using Targeted Therapies for Rheumatoid Arthritis: A Meta-Epidemiological Study

Objective

To determine if variations in trial eligibility criteria and patient baseline characteristics could be considered effect modifiers of the treatment response when testing targeted therapies (biological agents and targeted synthetic disease modifying antirheumatic drugs (DMARDs)) for rheumatoid arthritis (RA).

Methods

We conducted a meta-epidemiological study of all trials evaluating a targeted therapy approved by regulatory authorities for treating RA. The database search was completed on December 11^th 2013. Eligible trials reported ACR20 data at months 3–6 and used an add-on design. Odds ratios (ORs) were calculated from the response rates and compared among the trial eligibility criteria/patient baseline characteristics of interest. Comparisons are presented as the Ratio of Odds Ratios (ROR).

Results

Sixty-two trials (19,923 RA patients) were included in the primary analyses using ACR20 response. Overall, targeted therapies constituted an effective treatment (OR 3.96 95% confidence interval (CI) 3.41 to 4.60). The majority of the trial eligibility criteria and patient baseline characteristics did not modify treatment effect. The added benefit of targeted therapies was lower in trials including "DMARD-naïve" patients compared with trials including "DMARD inadequate responders" (ROR = 0.45, 95%CI 0.31 to 0.66) and trials including "targeted therapy inadequate responders" (0.50, 95%CI 0.29 to 0.87), test for interaction: p = 0.0002. Longer mean disease duration was associated with a higher likelihood of responding to treatment (β = 1.05, 95%CI 1.00 to 1.11 OR’s per year; p = 0.03). Analyses conducted using DAS28-remission as the outcome supported the above-mentioned findings.

Conclusion

Our results suggest that a highly selective inclusion is not associated with greater treatment effect, as might otherwise be expected. The added benefit of a targeted therapy was lower in trials including patients who were DMARD-naïve and trials including patients with shorter disease durations.     

DAS28: a useful instrument to monitor infliximab treatment in patients with rheumatoid arthritis

The Disease Activity Score using 28 joint counts (DAS28) has been developed in a cohort of patients with rheumatoid arthritis in which only conventional anti-rheumatic treatments were used. It has extensively been validated to monitor disease activity in daily clinical practice as well as in clinical trials. The study of Vander Cruyssen and colleagues showed that the DAS28 correlated best with the decisions of rheumatologists to increase the infliximab dose because of insufficient response. This result once more confirms the validity of the DAS28 to monitor disease activity in patients with rheumatoid arthritis and to titrate treatment with biologicals.     

Serum cartilage oligomeric matrix protein (COMP) decreases in rheumatoid arthritis patients treated with infliximab or etanercept

Changes in serum cartilage oligomeric matrix protein (COMP) were studied during a 6-month period from initiation of treatment of rheumatoid arthritis patients with either infliximab or etanercept, to elucidate whether the favourable results of tissue protection reported in clinical trials are corroborated by changing levels of circulating COMP. Rheumatoid arthritis patients commencing treatment with infliximab (N = 32) or etanercept (N = 17) were monitored in accordance with a structured protocol. Only patients who were not receiving glucocorticoids or who were on a stable dose of oral prednisolone (<10 mg daily) were included. Serum COMP was measured by a sandwich immunoassay based on two monoclonal antibodies against human COMP in samples obtained at treatment initiation and at 3 and 6 months. Serum COMP decreased at 3 months in both infliximab- and etanercept-treated patients (P < 0.001 and <0.005, respectively) and remained low at 6 months. There was no significant correlation between changes in or concentrations of serum COMP and serum C-reactive protein at any time point. A decrease in serum COMP was seen both in ACR20 responders (patients meeting the American College of Rheumatology criteria for 20% improvement) and in nonresponders. The pattern of changes of serum COMP, a marker for cartilage turnover, in these patient groups supports the interpretation that infliximab and etanercept have a joint protective effect. Serum COMP has potential as a useful marker for evaluating tissue effects of novel treatment modalities in rheumatoid arthritis.     

Positive anti-citrullinated protein antibody status and small joint arthritis are consistent predictors of chronic disease in patients with very early arthritis: results from the NOR-VEAC cohort

Introduction  

The current 1987 American College of Rheumatology (ACR) classification criteria for rheumatoid arthritis (RA) have proven less useful in early arthritis. The objective of this study was to identify and compare predictors of three relevant outcomes of chronic arthritis in a cohort of very early arthritis patients.     

B lymphocyte-typing for prediction of clinical response to rituximab

Introduction

The prediction of therapeutic response to rituximab in rheumatoid arthritis is desirable. We evaluated whether analysis of B lymphocyte subsets by flow cytometry would be useful to identify non-responders to rituximab ahead of time.

Methods

Fifty-two patients with active rheumatoid arthritis despite therapy with TNF-inhibitors were included in the national rituximab registry. DAS28 was determined before and 24 weeks after rituximab application. B cell subsets were analyzed by high-sensitive flow cytometry before and 2 weeks after rituximab administration. Complete depletion of B cells was defined as CD19-values below 0.0001 x10⁹ cells/liter.

Results

At 6 months 19 patients had a good (37%), 23 a moderate (44%) and 10 (19%) had no EULAR-response. The extent of B lymphocyte depletion in peripheral blood did not predict the success of rituximab therapy. Incomplete depletion was found at almost the same frequency in EULAR responders and non-responders. In comparison to healthy controls, non-responders had elevated baseline CD95⁺ pre-switch B cells, whereas responders had a lower frequency of plasmablasts.

Conclusions

The baseline enumeration of B lymphocyte subsets is still of limited clinical value for the prediction of response to anti-CD20 therapy. However, differences at the level of CD95+ pre switch B cells or plasmablasts were noticed with regard to treatment response. The criterion of complete depletion of peripheral B cells after rituximab administration did not predict the success of this therapy in rheumatoid arthritis.     

A network meta-analysis of randomized controlled trials of biologics for rheumatoid arthritis: a Cochrane overview

Background

We sought to compare the benefits and safety of 6 biologics (abatacept, adalimumab, anakinra, etanercept, infliximab and rituximab) in patients with rheumatoid arthritis.

Methods

In this network meta-analysis, we included all completed and updated Cochrane reviews on biologics for rheumatoid arthritis. We included data from all placebo-controlled trials that used standard dosing regimens. The major outcomes were benefit (defined as a 50% improvement in patient- and physician-reported criteria of the American College of Rheumatology [ACR50]) and safety (determined by the number of withdrawals related to adverse events). We used mixed-effects logistic regression to carry out an indirect comparison of the treatment effects between biologics.

Results

Compared with placebo, biologics were associated with a clinically important higher ACR50 rate (odds ratio [OR] 3.35, 95% confidence interval [CI] 2.62–4.29) and a number needed to treat for benefit of 4 (95% CI 4–6). However, biologics were associated with more withdrawals related to adverse events (OR 1.39, 95% CI 1.13–1.71), with a number needed to treat for harm of 52 (95% CI 29–152). Anakinra was less effective than all of the other biologics, although this difference was statistically significant only for the comparison with adalimumab (OR 0.45, 95% CI 0.21–0.99) and etanercept (OR 0.34, 95% CI 0.14–0.81). Adalimumab, anakinra and infliximab were more likely than etanercept to lead to withdrawals related to adverse events (adalimumab OR 1.89, 95% CI 1.18–3.04; anakinra OR 2.05, 95% CI 1.27–3.29; and infliximab OR 2.70, 95% CI 1.43–5.26).

Interpretation

Given the limitations of indirect comparisons, anakinra was less effective than adalimumab and etanercept, and etanercept was safer than adalimumab, anakinra and infliximab. This summary of the evidence will help physicians and patients to make evidence-based choices about biologics for the treatment of rheumatoid arthritis.Rheumatoid arthritis is one of the most common types of inflammatory arthritis, affecting 0.5%–1.0% of adults in Western countries.¹ Rheumatoid arthritis is associated with joint inflammation and destruction, which leads to major decrements in health-related quality of life,² functional limitations and work disability.^3,4In the last decade, several biologics have been approved, and their use has revolutionized the treatment of rheumatoid arthritis. These biologics are targeted therapies that dramatically inhibit the progression of joint damage in rheumatoid arthritis. These include inhibitors of tumour necrosis factor⁵ (infliximab, etanercept, adalimumab, certolizumab and golimumab), anti-interleukin 1 therapy (anakinra), anti-CD28 therapy (abatacept) and anti–B-cell therapy (rituximab). Biologics are recommended for use in patients with rheumatoid arthritis who have a suboptimal response or intolerance to traditional disease-modifying antirheumatic drugs, such as methotrexate. Although biologics have typically been compared with placebo, with both groups taking the same dose of methotrexate concomitantly, there have been no large randomized controlled trials comparing the biologics to one another. One randomized controlled trial included 2 biologics but compared both only to placebo and not to each other.⁶ Because of the high cost of biologics, different routes and administration schedules and different adverse event profiles, general practitioners and rheumatologists need to know their relative benefits and safety when deciding on treatment.One previous systematic review compared the benefits and safety of biologics using data from randomized and nonrandomized controlled trials. This review combined both recommended and nonrecommended doses;⁷ it found only one difference: infliximab was superior to anakinra in achieving a 20% improvement in the American College of Rheumatology response criteria for rheumatoid arthritis (ACR20). Overviews of systematic reviews for comparing and combining different systematic reviews assessing single agents have only recently been adopted by Cochrane.⁸ In the absence of direct head-to-head comparisons, we performed an overview of the sys tematic reviews of biologics for rheumatoid arthritis using network meta-analyses of updated Cochrane systematic reviews. We sought to provide estimates of the benefits and safety of biologics to assist patients and clinicians decide between biologics in clinical practice.     

Immune ablation and stem-cell therapy in autoimmune disease. Clinical experience

In the past 5 years, around 350 patients have received haematopoietic stem cell (HSC) transplantation for an autoimmune disease, with 275 of these registered in an international data base in Basel under the auspices of the European League Against Rheumatism (EULAR) and the European Group for Blood and Marrow Transplantation(EBMT). Most patients had either a progressive form of multiple sclerosis (MS; n = 88) or scleroderma (now called systemic sclerosis; n = 55). Other diseases were rheumatoid arthritis (Ra n = 40), juvenile idiopathic arthritis (JIA; n = 30), systemic lupus erythematosus (SLE; n = 20), idiopathic thrombocytopenic purpura (ITP; n = 7) and others. The procedure-related mortality was around 9%, with between-disease differences, being higher in systemic sclerosis and JIA and lower in RA (one death only). Benefit has been seen in around two-thirds of cases. No one regimen was clearly superior to another, with a trend toward more infectious complications with more intense regimens. Prospective, controlled randomized trials are indicated and being planned.     

Molecular targets in immune-mediated diseases: the case of tumour necrosis factor and rheumatoid arthritis

Rheumatoid arthritis is a common autoimmune condition in which, for unknown reasons, synovial joints become the target of a sustained immune response. For many years, rheumatoid arthritis was in the 'too hard basket' in terms of understanding disease mechanisms and providing rational therapy. This has changed dramatically over the last 10 years and rheumatoid arthritis is now at the forefront of biotechnology. In this review, we outline one of the most exciting recent developments, namely antagonists of the cytokine TNF. The preclinical evaluation of TNF in animal models of rheumatoid arthritis, and subsequent clinical trials of TNF inhibitors in patients, provides insight into the 'bench to bedside' paradigm. We therefore briefly review rheumatoid arthritis, animal models of rheumatoid arthritis, the biology of TNF, the pivotal clinical trials of TNF antagonists and the emerging data on side-effects. Tumour necrosis factor inhibitors in rheumatoid arthritis represent the first attempt to achieve sustained blockade of a single cytokine in a human disease. Whilst this approach has been even more successful than might have been predicted, we suggest it is only the beginning of what has become a new therapeutic era.     

Comparison of remission criteria in a tumour necrosis factor inhibitor treated rheumatoid arthritis longitudinal cohort: patient global health is a confounder

Introduction

Our objectives were to assess the frequency and sustainability of American College of Rheumatology (ACR)/European League against Rheumatism (EULAR) and Disease Activity Score (DAS)28(4v)–C-reactive protein (CRP) remission 12 months after the initiation of tumour necrosis factor inhibitor (TNFi) therapy in a rheumatoid arthritis (RA) cohort.

Methods

Data were collected of 273 biologic naive RA patients at baseline, then 3, 6 and 12 months post-TNFi therapy. Remission status was calculated using DAS28(4v)-CRP <2.6 and ACR/EULAR Boolean criteria. Response was scored using EULAR criteria.

Results

Mean (range) patient age was 59.9 (7.2-85.4) years with disease duration of 13.4 (1.0-52.0) years. Responder status maintained from 3–12 months (86%, 82.4%), laboratory/clinical parameters (erythrocyte sedimentation rate (ESR), CRP, patient global health (PGH), DAS28(4v)-CRP) also showed sustained improvement (P < 0.05). DAS28 remission was reached by 102 subjects at 1 year, 27 patients were in Boolean remission, but 75 missed it from the DAS28 remission group. Patients in remission were younger (P = 0.041) with lower baseline tender joint count (TJC)28 and PGH than those not in remission (P = 0.001, P = 0.047). DAS28 remission patients were older (P = 0.026) with higher 12 months PGH and subsequently higher DAS28 than Boolean remission patients (P < 0.0001). Patients not achieving Boolean remission due to missing one subcriteria most frequently missed PGH ≤1 criteria (79.8%).

Conclusions

Only 10% of this TNFi treated cohort achieved remission according to the new ACR/EULAR criteria, which requires lower disease activity. More stringent criteria may ensure further resolution of disease activity and better longterm radiographic outcome, which supports earlier intervention with biologic therapy in RA.     

Discriminant validity,responsiveness and reliability of the arthritis-specific Work Productivity Survey assessing workplace and household productivity in patients with psoriatic arthritis

Introduction

The novel arthritis-specific Work Productivity Survey (WPS) was developed to estimate patient productivity limitations associated with arthritis within and outside the home, which is an unmet need in psoriatic arthritis (PsA). The WPS has been validated in rheumatoid arthritis. This report assesses the discriminant validity, responsiveness and reliability of the WPS in adult-onset PsA.

Methods

Psychometric properties were assessed using data from the RAPID-PsA trial ({"type":"clinical-trial","attrs":{"text":"NCT01087788","term_id":"NCT01087788"}}NCT01087788) investigating certolizumab pegol (CZP) efficacy and safety in PsA. WPS was completed at baseline and every 4 weeks until Week 24. Validity was evaluated at baseline via known-groups defined using first and third quartiles of patients’ Disease Activity Score 28 based on C-reactive protein (DAS28(CRP)), Health Assessment Questionnaire-Disability Index (HAQ-DI), Short Form-36 (SF-36) items and PsA Quality of Life (PsAQoL) scores. Responsiveness and reliability were assessed by comparing WPS mean changes at Week 12 in American College of Rheumatology 20% improvement criteria (ACR20) or HAQ-DI Minimal Clinically Important Difference (MCID) 0.3 responders versus non-responders, as well as using standardized response means (SRM). All comparisons were conducted on the observed cases in the Randomized Set, regardless of the randomization group, using a non-parametric bootstrap-t method.

Results

Compared with patients with a better health state, patients with a worse health state had on average 2 to 6 times more household work days lost, more days with reduced household productivity, more days missed of family/social/leisure activities, more days with outside help hired and a significantly higher interference of arthritis per month. Among employed patients, those with a worse health state had 2 to 4 times more workplace days lost, more days with patient workplace productivity reduced, and a significantly higher interference of arthritis on patient workplace productivity versus patients with a better health state. WPS was also responsive to clinical changes, with responders having significantly larger improvements at Week 12 in WPS scores versus non-responders. The effect sizes for changes in productivity in ACR20 or HAQ-DI MCID responders were moderate (0.5 < SRM < 0.8) or small.

Conclusions

These analyses demonstrate the validity, responsiveness and reliability of the WPS, as an instrument for the measurement of patient productivity within and outside the home in an adult-onset PsA population.     

The interferon type I signature towards prediction of non-response to rituximab in rheumatoid arthritis patients

Introduction

B cell depletion therapy is efficacious in rheumatoid arthritis (RA) patients failing on tumor necrosis factor (TNF) blocking agents. However, approximately 40% to 50% of rituximab (RTX) treated RA patients have a poor response. We investigated whether baseline gene expression levels can discriminate between clinical non-responders and responders to RTX.

Methods

In 14 consecutive RA patients starting on RTX (test cohort), gene expression profiling on whole peripheral blood RNA was performed by Illumina^® HumanHT beadchip microarrays. Supervised cluster analysis was used to identify genes expressed differentially at baseline between responders and non-responders based on both a difference in 28 joints disease activity score (ΔDAS28 < 1.2) and European League against Rheumatism (EULAR) response criteria after six months RTX. Genes of interest were measured by quantitative real-time PCR and tested for their predictive value using receiver operating characteristics (ROC) curves in an independent validation cohort (n = 26).

Results

Genome-wide microarray analysis revealed a marked variation in the peripheral blood cells between RA patients before the start of RTX treatment. Here, we demonstrated that only a cluster consisting of interferon (IFN) type I network genes, represented by a set of IFN type I response genes (IRGs), that is, LY6E, HERC5, IFI44L, ISG15, MxA, MxB, EPSTI1 and RSAD2, was associated with ΔDAS28 and EULAR response outcome (P = 0.0074 and P = 0.0599, respectively). Based on the eight IRGs an IFN-score was calculated that reached an area under the curve (AUC) of 0.82 to separate non-responders from responders in an independent validation cohort of 26 patients using Receiver Operator Characteristics (ROC) curves analysis according to ΔDAS28 < 1.2 criteria. Advanced classifier analysis yielded a three IRG-set that reached an AUC of 87%. Comparable findings applied to EULAR non-response criteria.

Conclusions

This study demonstrates clinical utility for the use of baseline IRG expression levels as a predictive biomarker for non-response to RTX in RA.     

Immune ablation and stem-cell therapy in autoimmune disease: Immune ablation and stem-cell therapy in autoimmune disease - Clinical experience

In the past 5 years, around 350 patients have received haematopoietic stem cell (HSC) transplantation for an autoimmune disease, with 275 of these registered in an international data base in Basel under the auspices of the European League Against Rheumatism (EULAR) and the European Group for Blood and Marrow Transplantation(EBMT). Most patients had either a progressive form of multiple sclerosis (MS; n = 88) or scleroderma (now called systemic sclerosis; n = 55). Other diseases were rheumatoid arthritis (Ra n = 40), juvenile idiopathic arthritis (JIA; n = 30), systemic lupus erythematosus (SLE; n = 20), idiopathic thrombocytopenic purpura (ITP; n = 7) and others. The procedure-related mortality was around 9%, with between-disease differences, being higher in systemic sclerosis and JIA and lower in RA (one death only). Benefit has been seen in around two-thirds of cases. No one regimen was clearly superior to another, with a trend toward more infectious complications with more intense regimens. Prospective, controlled randomized trials are indicated and being planned.     

Effective rheumatoid arthritis treatment requires comprehensive management strategies

Work by Lee and colleagues has shown that decreased sleep quality and increased psychiatric distress increase pain sensitivity at both articular and nonarticular sites in rheumatoid arthritis (RA) patients. This work is consistent with prior studies showing that factors independent of RA disease activity can influence RA outcome measures. Owing to increasing pressure on rheumatologists to use outcome measures to inform treatment decisions, the work by Lee and colleagues highlights the need for comprehensive RA management strategies to understand and address the human factors that influence outcomes measures. Such strategies will ensure appropriate use of increasingly expensive therapies while maximizing patient satisfaction and reimbursement.