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.

An overview of biologic disease-modifying antirheumatic drugs in axial spondyloarthritis and psoriatic arthritis

Biologic disease-modifying antirheumatic drugs (bDMARDs) are engineered proteins with high affinity for various proinflammatory immune mediators to reduce inflammation and its sequelae in various rheumatic diseases. These medications, introduced at the advent of the 21st century, have revolutionized the treatment of axial spondyloarthritis (including ankylosing spondylitis) and psoriatic arthritis. Currently approved bDMARDs for axial spondyloarthritis are etanercept, infliximab, adalimumab, golimumab, certolizumab pegol, and secukinumab. For psoriatic arthritis, all of these drugs are approved in addition to ixekizumab, ustekinumab, abatacept, and tofacitinib. Selection of the optimal bDMARD should consider patient comorbidity including uveitis, psoriasis, and inflammatory bowel disease.

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

OBJECTIVE

To evaluate radiographic progression in the sacroiliac (SI) joints and to identify its predictors during long-term treatment (up to 6 years) with the tumor necrosis factor (TNF) inhibitor etanercept in patients with early axial spondyloarthritis (SpA).

METHODS

Patients with early axial SpA who were treated with etanercept for up to 6 years in the Etanercept versus Sulfasalazine in Early Axial Spondyloarthritis (ESTHER) trial were selected based on the availability of radiographs of the SI joints. Two readers who were blinded with regard to clinical data scored the radiographs according to the modified New York criteria (range 0-4 per SI joint). A sacroiliitis sum score (total range 0-8) was calculated as the mean of the scores of the 2 readers. Active and chronic inflammatory changes in the SI joints on magnetic resonance imaging (MRI) performed at baseline, year 2, and year 4 were assessed according to the Berlin MRI scoring system.

RESULTS

Of the 76 patients originally included in the study, 42 had radiographs of the SI joints available at baseline and at least 1 follow-up time point (year 2, 4, or 6). The mean ± SD change in the sacroiliitis sum score was 0.13 ± 0.73, -0.27 ± 0.76, and -0.09 ± 0.68, in the time intervals baseline to year 2, year 2 to year 4, and year 4 to year 6, respectively. In the longitudinal mixed model analysis, elevated C-reactive protein level (β = 0.58 [95% confidence interval 0.24, 0.91]) and MRI SI joint osteitis score (β = 0.06 [95% confidence interval 0.03, 0.10]) were independently associated with progression of the sacroiliitis sum score.

CONCLUSION

Our findings indicate that long-term anti-TNF therapy decelerates the progression of structural damage in the SI joints. Elevated CRP level and presence of osteitis on MRI were independently associated with radiographic sacroiliitis progression.

A Review on the Effect of Tumor Necrosis Factor Inhibitors on Structural Progression in Early Axial Spondyloarthritis Using Magnetic Resonance Imaging

INTRODUCTION

Considering the progressive nature of axial spondyloarthritis (axSpA), it is important to determine whether tumor necrosis factor alpha (TNFα) inhibitors have an effect on early inflammatory and structural lesions detected using magnetic resonance imaging (MRI).

METHODS

A search of MEDLINE/PubMed for full-text, English-language articles on randomized controlled trials (RCTs) of adalimumab, certolizumab, etanercept, golimumab, or infliximab published since January 2007 was conducted in February 2018 and again in December 2018. The collected articles reported on inflammatory or fatty lesion progression in the spine or sacroiliac joint (SIJ), determined using MRI, in a population that included at least 40% of patients with early axSpA, defined as non-radiographic axSpA.

RESULTS

Of the 105 articles retrieved, 19 were included in this review, of which the majority were on etanercept (n = 11). A majority of selected articles included information on inflammatory lesions (SIJ 15/19; spine 12/19). All five TNFα inhibitors showed benefits on inflammation, assessed by MRI, in patients with early axSpA for up to 204 weeks of treatment. Structural progression in SIJ and the spine was assessed in 6/19 and 3/19 articles, respectively, with mixed evidence on benefits of TNF-inhibitor treatment.

CONCLUSIONS

In conclusion, treatment with TNFα inhibitors reduces MRI-evident inflammatory lesions in the SIJ and spine of patients with early axSpA for up to 4 years. There is less evidence of benefits on structural lesions. Additional studies are required to determine whether TNFα-inhibitor therapy can limit or delay radiological progression in patients with early axSpA.

FUNDING

Pfizer.

Structural progression rate decreases over time on serial radiography and magnetic resonance imaging of sacroiliac joints and spine in a five-year follow-up study of patients with ankylosing spondylitis treated with tumour necrosis factor inhibitor

OBJECTIVE

To investigate temporal changes in structural progression assessed by serial conventional radiography and magnetic resonance imaging (MRI) of the sacroiliac joints (SIJs) and spine in patients with ankylosing spondylitis (AS) treated with tumour necrosis factor (TNF) inhibitor for 5 years.

METHOD

Forty-two patients were included and 33 patients were followed for 5 years in a prospective investigator-initiated study. Conventional radiographs were required four times and MRI seven times. The modified Stoke Ankylosing Spondylitis Spinal Score (mSASSS); Spondyloarthritis Research Consortium of Canada (SPARCC) MRI SIJ and Spine Inflammation, and SPARCC MRI SIJ Structural Score (SSS) for Fat, Erosion, Backfill, and Ankylosis; and the Canada-Denmark MRI scores for Spine Inflammation, Fat, Erosion, and New Bone Formation (NBF) were applied.

RESULTS

Compared with baseline, MRI Inflammation had decreased significantly at week 22 (spine)/week 46 (SIJ) and thereafter. MRI SIJ Fat (from week 22), SIJ Ankylosis, Spine NBF, and mSASSS had increased significantly at week 46 and thereafter. SIJ Erosion had decreased from year 2. The annual progression rate in mSASSS was significantly higher during weeks 0-46 compared to week 46 to year 3. In multivariate regression analyses, baseline SIJ Inflammation and Backfill were independent predictors of 5 year progression in SIJ Ankylosis. Spine Erosion predicted progression in Spine NBF. Longitudinally, Ankylosing Spondylitis Disease Activity Score, Bath Ankylosing Spondylitis Disease Activity Index, MRI Spine Inflammation, Fat, and Erosion scores were significantly associated with mSASSS. SIJ Inflammation, Fat, Erosion, and Backfill scores were longitudinally associated with SIJ Ankylosis. Structural progression was not associated with body mass index, smoking, or Assessment of SpondyloArthritis international Society Non-Steroidal Anti-Inflammatory Drug Index.

CONCLUSION

In a 5 year follow-up study of patients with AS treated with TNF inhibitor, structural progression decreased over time.

Whole-body Magnetic Resonance Imaging in Inflammatory Arthritis: Systematic Literature Review and First Steps Toward Standardization and an OMERACT Scoring System

OBJECTIVE

Whole-body magnetic resonance imaging (WB-MRI) is a relatively new technique that can enable assessment of the overall inflammatory status of people with arthritis, but standards for image acquisition, definitions of key pathologies, and a quantification system are required. Our aim was to perform a systematic literature review (SLR) and to develop consensus definitions of key pathologies, anatomical locations for assessment, a set of MRI sequences and imaging planes for the different body regions, and a preliminary scoring system for WB-MRI in inflammatory arthritis.

METHODS

An SLR was initially performed, searching for WB-MRI studies in arthritis, osteoarthritis, spondyloarthritis, or enthesitis. These results were presented to a meeting of the MRI in Arthritis Working Group together with an MR image review. Following this, preliminary standards for WB-MRI in inflammatory arthritides were developed with further iteration at the Working Group meetings at the Outcome Measures in Rheumatology (OMERACT) 2016.

RESULTS

The SLR identified 10 relevant original articles (7 cross-sectional and 3 longitudinal, mostly focusing on synovitis and/or enthesitis in spondyloarthritis, 4 with reproducibility data). The Working Group decided on inflammation in peripheral joints and entheses as primary focus areas, and then developed consensus MRI definitions for these pathologies, selected anatomical locations for assessment, agreed on a core set of MRI sequences and imaging planes for the different regions, and proposed a preliminary scoring system. It was decided to test and further develop the system by iterative multireader exercises.

CONCLUSION

These first steps in developing an OMERACT WB-MRI scoring system for use in inflammatory arthritides offer a framework for further testing and refinement.

Serum C-reactive Protein Levels Demonstrate Predictive Value for Radiographic and Magnetic Resonance Imaging Outcomes in Patients with Active Ankylosing Spondylitis Treated with Golimumab

OBJECTIVE

Serum C-reactive protein (CRP) associates with radiographic progression in patients with ankylosing spondylitis (AS) untreated with tumor necrosis factor (TNF) antagonists. We assessed correlations between serum CRP and radiographic progression/magnetic resonance imaging (MRI)-detected inflammation after 2 years of anti-TNF therapy.

METHODS

Patients with active AS receiving golimumab (GOL)/placebo through Week 16 (early escape) or Week 24 (crossover by design), followed by GOL through 4 years, had sera/images obtained through Week 208. Lateral spinal radiographs and spinal MRI were scored with the modified Stoke AS Spine Score (mSASSS) and the AS spine MRI activity (ASspiMRI-a) score, respectively. ANOVA assessed differences based on CRP levels and mSASSS progression. The relationships between CRP levels and mSASSS/ASspiMRI-a were assessed by Spearman correlation and logistic regression.

RESULTS

Of the randomized GO-RAISE patients, 299 (84.0%) had pre- and posttreatment spinal radiographs. Larger proportions of patients with Week 104 CRP ≥ 0.5 mg/dl (n = 47) versus < 0.5 mg/dl (n = 236, 40.4% vs 22.9%, p = 0.0121) had mSASSS changes ≥ 2 at Week 104. Across several visits, serum CRP demonstrated weak associations with mSASSS change (rs ≤ 0.21, p < 0.05, n = 262-293) and moderate associations with ASspiMRI-a change (rs = -0.33 to 0.54, p < 0.05, n = 65-89). Higher baseline CRP was associated with increased risk for syndesmophytes at Week 104/Week 208, and large, short-term decreases in CRP from baseline to Week 14/Week 24 also yielded increased syndesmophyte formation risk.

CONCLUSION

Elevated CRP after 2 years of anti-TNF treatment correlated with greater radiographic progression risk at 4 years. Elevated CRP at baseline or Week 14/Week 24 of anti-TNF treatment weakly predicted subsequent radiographic progression and modestly predicted residual spinal inflammation in patients with AS treated with anti-TNF. Findings are useful regarding new treatment options in patients treated with anti-TNF. ClinicalTrials.gov: NCT00265083.

Challenges of diagnosis and management of axial spondyloarthritis in North Africa and the Middle East: An expert consensus

Axial spondyloarthritis (SpA) is a spectrum of inflammatory disease with stages characterized by both nonradiographic and radiographic sacroiliitis. Nonradiographic axial SpA is associated with health-related quality-of-life impairment and may progress to ankylosing spondylitis. Axial SpA has a low prevalence in some countries in North Africa and the Middle East, and pooling of data and resources is needed to increase understanding of the regional picture. Early diagnosis and effective treatment are required to reduce disease burden and prevent progression. Anti-TNF therapy is recommended for patients with persistently high disease activity despite conventional treatment, and has been shown to be effective in patients without radiographic damage. Diagnostic delays can be an obstacle to early treatment and appropriate referral strategies are needed. In some countries, restricted access to magnetic resonance imaging and anti-TNF agents presents a challenge. In this article, a group of experts from North Africa and the Middle East evaluated the diagnosis and management of axial SpA with particular reference to this region.