Progression of Structural Damage in the Sacroiliac Joints in Patients With Early Axial Spondyloarthritis During Long-Term Anti-Tumor Necrosis Factor Treatment: Six-Year Results of Continuous Treatment With Etanercept

Disease course of non-radiographic axial spondyloarthritis: Data from a long-term retrospective observational cohort

BACKGROUND

Disease course of non-radiographic axial spondyloarthritis (axSpA) has been extensively studied in non-Asian population; however, there are limited data in Asian population. This study aimed to evaluate the long-term disease course of non-radiographic axSpA in Asian patients and identify factors associated with progression to radiographic axSpA.

METHODS

In this retrospective observational cohort study, 56 Korean patients newly diagnosed with non-radiographic axSpA between 2006 and 2015 were included. All patients fulfilled the Assessment of SpondyloArthritis international Society classification criteria for axSpA, and did not fulfil the radiological criterion of the 1984 modified New York criteria. Disease course was assessed by the rate of progression to radiographic axSpA. Factors associated with the risk of progression to radiographic axSpA were assessed using multivariable Cox proportional hazard regression analysis.

RESULTS

The mean age at baseline was 31.4±13.3 years, and 37 (66.1%) patients were men. Over a mean observation period of 8.4±3.7 years, 28 (50.0%) patients progressed to radiographic axSpA. In multivariable Cox proportional hazard regression analysis, the presence of syndesmophytes at diagnosis (adjusted hazard ratio [HR]: 4.50, 95% confidence interval [CI]: 1.54-13.15, p = 0.006) and active sacroiliitis on magnetic resonance imaging (MRI) at diagnosis (adjusted HR: 5.88, 95% CI: 2.05-16.82, p = 0.001) were significantly associated with a higher risk of progression to radiographic axSpA, whereas longer exposure to tumor necrosis factor inhibitors (TNFis) was significantly associated with a lower risk of progression to radiographic axSpA (adjusted HR: 0.89, 95% CI: 0.80-0.98, p = 0.022).

CONCLUSION

During long-term follow-up, a substantial proportion of Asian patients with non-radiographic axSpA progressed to radiographic axSpA. The presence of syndesmophytes and active sacroiliitis on MRI at the time of non-radiographic axSpA diagnosis were associated with a higher risk of progression to radiographic axSpA, while longer exposure to TNFis was associated with a lower risk of progression to radiographic axSpA.

Significance of structural changes in the axial skeleton in patients with axial spondyloarthritis: how important are lesions in the sacroiliac joint?

Inflammatory back pain (IBP) is a characteristic clinical symptom of patients with axial spondyloarthritis (axSpA) that is caused by inflammation in the axial skeleton. In early disease stages the sacroiliac joints (SIJ) are most often affected, the spine usually at later stages. In many but clearly not all cases of axSpA new bone formation in form of syndesmophytes and ankylosis occur in the further course of the disease. Function and mobility may be impaired by both, inflammation and structural changes. In clinical trials outcome parameters most often used refer to pain, disease activity, function, mobility and global health but many researchers are also interested in radiographic progression in the axial skeleton of patients with axSpA. This viewpoint discusses the relevance of structural changes in the SIJ in comparison to the spine and in relation to functional outcomes and mobility.

Sacroiliac joint radiographic progression in axial spondyloarthritis is retarded by the therapeutic use of TNF inhibitors: 12-year data from the SCQM registry

OBJECTIVES

To analyse the effect of tumour necrosis factor inhibitors (TNFi) on sacroiliac joint (SIJ) radiographic progression in axial spondyloarthritis (axSpA).

METHODS

Patients with axSpA in the Swiss Clinical Quality Management cohort with up to 12 years of follow-up and radiographic assessments every 2 years were included. SIJs were scored by two readers according to the modified New York criteria blinded to chronology. The relationship between TNFi use before or during a 2-year radiographic interval and SIJ progression was investigated using generalised estimating equation models with adjustment for potential confounding. Progression was defined as worsening of ≥1 grade in ≥1 SIJ and ignoring a change from 0 to 1 over 2 years, if both readers agreed. A third reading of radiographs was integrated in sensitivity analyses.

RESULTS

A total of 515 patients with axSpA contributed to data for 894 radiographic intervals (24 progression events). In patients with complete covariate data, prior use of TNFi reduced the odds of progression (OR 0.21, 95% CI 0.07 to 0.65). A comparable effect was found for use of TNFi for ≥1 year within a 2-year radiographic interval (OR 0.21, 95% CI 0.08 to 0.55). The inhibitory impact of TNFi was confirmed if progression was demonstrated in 2/3 readings: OR 0.50, 95% CI 0.28 to 0.89 and OR 0.46, 95% CI 0.27 to 0.78 for TNFi treatment before and for ≥1 year within the interval, respectively.

CONCLUSION

TNFi are associated with deceleration of SIJ radiographic progression in patients with axSpA if treatment is continued for ≥1 year.

Effects of ixekizumab treatment on structural changes in the sacroiliac joint: MRI assessments at 16 weeks in patients with non-radiographic axial spondyloarthritis

BACKGROUND

There is limited understanding regarding the inhibition of structural damage in the sacroiliac joint of patients with non-radiographic axial spondyloarthritis. This study evaluated the effect of the interleukin-17A inhibitor ixekizumab versus placebo on structural lesions in the sacroiliac joints as assessed by MRI at week 16 in patients with non-radiographic axial spondyloarthritis from the COAST-X study.

METHODS

COAST-X was a 52-week, randomised, double-blind, placebo-controlled, parallel-group study done at 107 sites in 15 countries in Europe, Asia, North America, and South America. Eligible participants were adults (aged ≥18 years) with active axial spondyloarthritis without definite radiographic sacroiliitis (non-radiographic axial spondyloarthritis), objective signs of inflammation (via MRI or C-reactive protein), and an inadequate response or intolerance to non-steroidal anti-inflammatory drugs. Patients were randomly allocated to placebo or double-blind ixekizumab 80 mg every 4 weeks (Q4W) or 2 weeks (Q2W), with an 80 mg or 160 mg starting dose. We report a post-hoc analysis of 266 patients with available MRI scans from baseline and week 16. MRI scans were scored using the Spondyloarthritis Research Consortium of Canada (SPARCC) sacroiliac joint structural score (SSS) method independently by two masked readers. Treatment comparisons used analysis of covariance based on observed cases. Correlations were evaluated among changes in SPARCC SSS for erosion, fat lesions, and backfill, and between changes in SPARCC SSS and sacroiliac joint inflammation scores and clinical measures. COAST-X was registered with ClinicalTrials.gov, NCT02757352.

FINDINGS

Between Aug 2, 2016, and Jan 29, 2018, 303 patients were enrolled to the COAST-X study. 290 (96%) of 303 participants completed the week 16 visit (95 in the ixekizumab Q4W group, 98 in the ixekizumab Q2W group, and 97 in the placebo group), and MRI scans were available for 266 patients at baseline and week 16 (85 in the ixekizumab Q4W group, 91 in the ixekizumab Q2W group, and 90 in the placebo group). Changes from baseline to week 16 in mean SPARCC SSS for erosion were -0·39 for ixekizumab Q4W (p=0·003 vs placebo), -0·40 for ixekizumab Q2W (p=0·002), and 0·16 for placebo; for fat lesions: 0·16 for ixekizumab Q4W (p=0·013), 0·10 for ixekizumab Q2W (p=0·067), and -0·04 for placebo; and for backfill: 0·21 for ixekizumab Q4W (p=0·011), 0·22 for ixekizumab Q2W (p=0·006), and -0·10 for placebo. Ankylosis did not change. Effects of ixekizumab versus placebo on structural changes were most pronounced in patients with baseline inflammation in the sacroiliac joints. Changes from baseline at week 16 in erosion, fat lesions, and backfill were correlated.

INTERPRETATION

Although the clinical relevance is not yet clear, patients with non-radiographic axial spondyloarthritis receiving ixekizumab had significant reductions in erosions and increases in fat lesions and backfill in the sacroiliac joints versus placebo at week 16, suggesting an early repair process with ixekizumab treatment.

FUNDING

Eli Lilly and Company.

Treatment with Tumour Necrosis Factor Inhibitors is Associated with a Time-Shifted Retardation of Radiographic Sacroiliitis Progression in Patients with Axial Spondyloarthritis: 10-year Results from the German Spondyloarthritis Inception Cohort

OBJECTIVES

To investigate the longitudinal association between radiographic sacroiliitis progression and treatment with tumour necrosis factor inhibitors (TNFi) in patients with early axial Spondyloarthritis (axSpA) in a long-term inception cohort.

METHODS

We included patients from the German Spondyloarthritis Inception Cohort who had baseline plus at least one sacroiliac radiograph during follow-up. Two central readers scored the radiographs according to modified New York criteria. The sacroiliac sum score was calculated as a mean of both readers. TNFi use was assessed according to exposure in the current and/or previous 2-year radiographic interval. The association between TNFi use and radiographic sacroiliitis progression was examined by longitudinal generalized estimating equations analysis with adjustment for potential confounders.

RESULTS

In total, 301 axSpA patients (166 non-radiographic [nr-axSpA] and 135 radiographic [r-axSpA]) contributed 737 radiographic intervals. While receiving ≥12 months TNFi in the previous interval was associated with a significant decrease in the sacroiliitis sum score (β=-0.09 [95% CI -0.18, -0.01], adjusted for age, sex, symptom duration, HLA-B27 status, Bath Ankylosing Spondylitis Disease Activity Index [BASDAI], C-reactive protein [CRP], and Non-steroidal anti-inflammatory drugs [NSAIDs] intake), this was not the case in patients who received TNFi in the current interval (β=0.05 [95% CI -0.05, 0.14]). This effect was stronger in patients with nr-axSpA as compared to patients with r-axSpA (β=-0.16 [95% CI -0.28, -0.03] vs β=-0.04 [95% CI -0.15, 0.07], respectively).

CONCLUSION

TNFi was associated with reduction of radiographic sacroiliitis progression in patients with axSpA. This effect became evident between 2 and 4 years after treatment initiation.

Disease modification in ankylosing spondylitis with TNF inhibitors: spotlight on early phase clinical trials

INTRODUCTION

Ankylosing spondylitis (AS) is a chronic inflammatory disease whose main hallmark is involvement of the axial skeleton. Non-steroidal anti-inflammatory drugs (NSAIDs) are the first line treatment; however, their use is limited because of side effects. Tumor necrosis factor inhibitors (TNFi) are a safe and effective therapy, and they have been approved for the management of AS.

AREAS COVERED

This is a review of the efficacy of TNFi in disease modification in AS. It is focused on results from early-phase clinical trials; however, it also discusses the most relevant findings in order to optimize anti-TNF treatment. A literature search was done using PubMed, Medline, Embase, Google Scholar, and Cochrane library, looking for scientific publications from inception to August 2021. Further information was retrieved from ClinicalTrial.gov and Clinicaltrialsregister.eu.

EXPERT OPINION

TNFi have demonstrated short- and long-term improvements in all aspects of disease activity, as well as physical function in patients with AS. They have drastically revolutionized the management of the disease; and even though new drugs have become available in the market, TNFi has not been displaced for the treatment of AS, and still constitute the best alternative when NSAIDs are no-longer an option.

ACR Appropriateness Criteria® Inflammatory Back Pain: Known or Suspected Axial Spondyloarthritis: 2021 Update

Inflammatory back pain is a hallmark feature of axial spondyloarthritis, a heterogeneous group of inflammatory disorders which affects the sacroiliac joints and spine. Imaging plays a key role in diagnosis of this disease and in facilitating appropriate treatment. This document provides evidence-based recommendations on the appropriate use of imaging studies during multiple stages of the clinical evaluation of patients with suspected or known axial spondyloarthritis. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Significance of structural changes in the sacroiliac joints of patients with axial spondyloarthritis detected by MRI related to patients symptoms and functioning

Axial spondyloarthritis (axSpA) is a chronic inflammatory rheumatic disease that manifests primarily in the axial skeleton, initially mostly in the sacroiliac joints (SIJ), usually later spreading to the spine. The disease is characterised by inflammation and new bone formation which are mainly assessed by conventional radiography (CR) and magnetic resonance imaging (MRI). Tumour necrosis factor inhibitors (TNFi) and interleukin-17 antagonists have been shown to be efficacious and efficient in patients with axSpA. This treatment seems to also inhibit structural damage, for example, retard radiographic progression. Indeed, a reduction of new bone formation in the spine, as assessed by CR, has been reported to occur after at least 2 years of therapy with TNFi. Recently, a reduction of erosions and ankylosis in the SIJ has also been observed in axSpA patients treated with etanercept and filgotinib. In this narrative review, we discuss the limited significance of such findings.

Sustained clinical response and safety of etanercept in patients with early axial spondyloarthritis: 10-year results of the ESTHER trial

Aims:

Long-term data on TNFi treatment in patients with axSpA is scarce. The objective of this analysis was to assess long-term clinical efficacy of etanercept in early axSpA [including both non-radiographic and radiographic axSpA forms], who participated in the long-term (until year 10) extension of the ESTHER-trial.

Methods:

In the previously reported ESTHER-trial, patients with early active axSpA were randomized to treatment with etanercept (n = 40) or sulfasalazine (n = 36) during the first year. Patients in remission discontinued their therapy and were followed up until the end of year 2; in case of remission-loss, etanercept was (re)-introduced and continued until the end of year 10. If remission was not achieved at year 1, patients continued receiving (or were switched to) etanercept for up to 10 years.

Results:

A total of 19 patients (12 with r-axSpA and 7 with nr-axSpA at baseline) out of the initial 76 patients (= 25%) completed year 10 of the study. In the entire group, a sustained clinical response was seen over 10 years of follow up in the as-observed analysis. Completers were significantly more often male and showed lower values of patient and physician global assessments of disease activity, Ankylosing Spondylitis Disease Activity Score (ASDAS), and Ankylosing Spondylitis Quality of Life questionnaire (ASQoL) scores at baseline as compared with non-completers. When analyzing clinical data of the completers, mean Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Bath Ankylosing Spondylitis Functional Index (BASFI) values were constantly below 2 and mean ASDAS below 2.1 during follow up with no statistically significant differences between the r-axSpA and nr-axSpA subgroups. A total of 39 serious adverse events were documented over the 10 years, while six of them were seen as possibly associated with the etanercept treatment, which led in five patients to treatment discontinuation.

Conclusion:

A sustained clinical response was observed over the 10 years of the study with comparable response and drop-out rates between r-axSpA and nr-axSpA. Etanercept was well tolerated across the entire treatment period and showed a good safety profile with no new safety signals.

Conventional disease-modifying antirheumatic drugs therapy may not slow spinal radiographic progression in ankylosing spondylitis: results from an 18-year longitudinal dataset

Objectives:

The clinical benefit of conventional disease-modifying antirheumatic drugs (cDMARDs) for treating ankylosing spondylitis (AS) is generally limited to improvements in peripheral arthritis. However, cDMARDs could be conditionally considered as alternatives to established drugs for improving axial manifestations in exceptional circumstances. However, there are few studies of the impact of cDMARDs on radiographic progression outcomes. Therefore, we investigated the effectiveness of cDMARDs on radiographic progression in AS.

Methods:

Among 1280 AS patients at a single hospital from 2000 to 2018, 301 who had been treated with sulfasalazine (SSZ) or methotrexate (MTX) were enrolled. For each patient, the entire follow-up period was split into 1-year intervals. Each interval was classified as either an “on-cDMARD” interval, which was a period of treatment with SSZ alone, MTX alone, or a combination of SSZ and MTX, or an “off-cDMARD” interval, which was a period without cDMARD treatment. Radiographic progression was scored using the modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS). The relationship between cDMARD use and radiographic progression within the intervals, defined as the rate of mSASSS progression, was investigated using linear models with adjustment for potential confounding covariates and for clustering among observations from the same patient.

Results:

The 732 on-cDMARD intervals and 1027 off-cDMARD intervals were obtained from enrolled patients. In multivariable regression analysis, there was no significant association between cDMARDs and the rate of mSASSS progression (β = −0.081, p = 0.418). The mean adjusted mSASSS change per year was 0.610 from on-cDMARD intervals and 0.691 from off-cDMARD intervals.

Conclusion:

Treatment with cDMARDs may not reduce radiographic progression in AS patients.

[Imaging in patients with axial spondylarthritis with focus on new bone formation]

To summarize, the currently available imaging procedures have various possibilities to visualize or sometimes to predict the osteogenesis pathognomonic for axial spondylarthritis (axSpA). The individual imaging techniques of X‑rays, computed tomography (CT) and magnetic resonance imaging (MRI) all have strengths and weaknesses in the diagnostics of axSpA. The generally easily available X‑ray imaging rapidly provides information on the condition of large sections of the skeleton. In particular, it can depict the chronic stages with various structural alterations of the sacroiliac joint and syndesmophytes and ankylosis of the spine. The CT technique, which principally has the same contrast as X‑rays, also shows pathological ossifications but without superimpositions, with better resolution of details and a higher dimensionality. The MRI technique has a superior soft tissue contrast so that acute inflammatory stages, such as bone marrow edema and erosion of the edges of vertebrae of the spine (shiny corners, Romanus lesions) or erosions and bone marrow edema of the sacroiliac joint are easily visible. Bony reconstruction processes can be visualized better in X‑ray imaging and particularly in CT, which increases the evidential value of X‑ray, CT and MRI techniques. The positions of conventional radiography and MRI are well-established in the diagnostic algorithm; however, low-dose CT of the spine is still in the experimental stage but the initial results look promising.

Treat to Target in Axial Spondyloarthritis

This article discusses treat-to-target strategies in axial spondyloarthritis and current status. Treatment ranging from nonsteroidal anti-inflammatory drugs to biologic and other disease-modifying drugs is discussed in the context of treat-to-target. The article explores evidence from landmark randomized, controlled trials and observational studies focusing on both radiographic and nonradiographic axial spondyloarthritis. The feasibility of treat-to-target, as well as predictors of remission are addressed in line with existing evidence. Finally, issues around management principles and challenges, as well as unmet need in the field, are highlighted.