A Randomized, Double-Blind Trial of Abatacept (CTLA-4Ig) for the Treatment of Giant Cell Arteritis

CD28 Signaling Controls Metabolic Fitness of Pathogenic T Cells in Medium and Large Vessel Vasculitis

BACKGROUND

In giant cell arteritis, vessel-wall infiltrating CD4 T cells and macrophages form tissue-destructive granulomatous infiltrates, and the artery responds with a maladaptive response to injury, leading to intramural neoangiogenesis, intimal hyperplasia, and luminal occlusion. Lesion-residing T cells receive local signals, which represent potential therapeutic targets.

OBJECTIVES

The authors examined how CD28 signaling affects vasculitis induction and maintenance, and which pathogenic processes rely on CD28-mediated T-cell activation.

METHODS

Vasculitis was induced by transferring peripheral blood mononuclear cells from giant cell arteritis patients into immunodeficient NSG mice engrafted with human arteries. Human artery-NSG chimeras were treated with anti-CD28 domain antibody or control antibody. Treatment effects and immunosuppressive mechanisms were examined in vivo and in vitro applying tissue transcriptome analysis, immunohistochemistry, flow cytometry, and immunometabolic analysis.

RESULTS

Blocking CD28-dependent signaling markedly reduced tissue-infiltrating T cells and effectively suppressed vasculitis. Mechanistic studies implicated CD28 in activating AKT signaling, T-cell proliferation and differentiation of IFN-γ and IL-21-producing effector T cells. Blocking CD28 was immunosuppressive by disrupting T-cell metabolic fitness; specifically, the ability to utilize glucose. Expression of the glucose transporter Glut1 and of glycolytic enzymes as well as mitochondrial oxygen consumption were all highly sensitive to CD28 blockade. Also, induction and maintenance of CD4+CD103+ tissue-resident memory T cells, needed to replenish the vasculitic infiltrates, depended on CD28 signaling. CD28 blockade effectively suppressed vasculitis-associated remodeling of the vessel wall.

CONCLUSIONS

CD28 stimulation provides a metabolic signal required for pathogenic effector functions in medium and large vessel vasculitis. Disease-associated glycolytic activity in wall-residing T-cell populations can be therapeutically targeted by blocking CD28 signaling.

2018 EULAR recommendations for a core data set to support observational research and clinical care in giant cell arteritis

Giant cell arteritis (GCA) represents the most common form of primary systemic vasculitis and is frequently associated with comorbidities related to the disease itself or induced by the treatment. Systematically collected data on disease course, treatment and outcomes of GCA remain scarce. The aim of this EULAR Task Force was to identify a core set of items which can easily be collected by experienced clinicians, in order to facilitate collaborative research into the course and outcomes of GCA. A multidisciplinary EULAR task force group of 20 experts including rheumatologists, internists, epidemiologists and patient representatives was assembled. During a 1-day meeting, breakout groups discussed items from a previously compiled collection of parameters describing GCA status and disease course. Feedback from breakout groups was further discussed. Final consensus was achieved by means of several rounds of email discussions after the meeting. A three-round Delphi survey was conducted to determine a core set of parameters including the level of agreement. 117 parameters were regarded as relevant. Potential items were subdivided into the following categories: General, demographics, GCA-related signs and symptoms, other medical conditions and treatment. Possible instruments and assessment intervals were proposed for documentation of each item. To facilitate implementation of the recommendations in clinical care and clinical research, a minimum core set of 50 parameters was agreed. This proposed core set intends to ensure that relevant items from different GCA registries and databases can be compared for the dual purposes of facilitating clinical research and improving clinical care.

Effect of Treatment on Imaging, Clinical, and Serologic Assessments of Disease Activity in Large-vessel Vasculitis

OBJECTIVE

Disease activity in large-vessel vasculitis (LVV) is traditionally assessed by clinical and serological variables rather than vascular imaging. This study determined the effect of treatment on 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) vascular activity in relation to clinical- and serologic-based assessments.

METHODS

Patients with giant cell arteritis (GCA) or Takayasu arteritis (TA) were prospectively evaluated at 6-month intervals in an observational cohort. Treatment changes were made at least 3 months before the followup visit and categorized as increased, decreased, or unchanged. Imaging (FDG-PET qualitative analysis), clinical, and serologic (erythrocyte sedimentation rate, C-reactive protein) assessments were determined at each visit and compared over interval visits.

RESULTS

Serial assessments were performed in 52 patients with LVV (GCA = 31; TA = 21) over 156 visits. Increased, decreased, or unchanged therapy was recorded for 36-, 23-, and 32-visit intervals, respectively. When treatment was increased, there was significant reduction in disease activity by imaging, clinical, and inflammatory markers (p ≤ 0.01 for each). When treatment was unchanged, all 3 assessments of disease activity remained similarly unchanged over 6-month intervals. When treatment was reduced, PET activity significantly worsened (p = 0.02) but clinical and serologic activity did not significantly change. Treatment of GCA with tocilizumab and of TA with tumor necrosis factor inhibitors resulted in significant improvement in imaging and clinical assessments of disease activity, but only rarely did the assessments both become normal.

CONCLUSION

In addition to clinical and serologic assessments, vascular imaging has potential to monitor disease activity in LVV and should be tested as an outcome measure in randomized clinical trials.

Current advances in the treatment of giant cell arteritis: the role of biologics

Giant cell arteritis (GCA) is the most common form of systemic vasculitis. It is a potentially severe disease with 25% of patients suffering vision loss or stroke. Our treatment paradigm is based on glucocorticoids. Glucocorticoids are required in high doses for prolonged periods and subsequently are associated with a significant amount of treatment-related morbidity. Alternative treatment options are urgently needed to minimize these glucocorticoid adverse events. Many other agents, such as methotrexate and tumour necrosis factor alpha inhibitors have been used in GCA, with limited or no evidence of benefit. Our emerging understanding of the pathogenic processes involved in GCA has led to an increased interest in the use of biologic agents to treat the disease. Two randomized controlled trials have recently reported dramatic effects of the use of the interleukin-6 targeted biologic tocilizumab in GCA, with significant increases in remission rates and decreases in glucocorticoid burden. While encouraging, longer-term and additional outcomes are awaited to clarify the exact positioning of tocilizumab in the treatment approach. Emerging data for other biologic agents, particularly abatacept and ustekinumab, are also encouraging but less well advanced. We are at the dawn of a new era in GCA treatment, but uncertainties and opportunities abound.

Pathophysiology of large vessel vasculitis and utility of interleukin-6 inhibition therapy

Takayasu arteritis (TAK) and giant cell arteritis (GCA) affect mainly large- and medium-sized arteries. In refractory cases, vascular remodeling progresses and leads to serious outcomes. Studies have demonstrated that cytokines such as interleukin (IL)-6 play crucial roles in the pathophysiology of TAK and GCA. Recently, randomized controlled trials on IL-6 inhibition therapy using tocilizumab (TCZ) were performed, and significant effects were exhibited. The purposes of conventional treatments have been to improve symptoms and decrease the levels of inflammatory markers. Arterial changes have been considered as damages. However, after TCZ came into practical use, establishment of treat to target is desired to prevent vascular remodeling. In contrast, a combination therapy of glucocorticoids (GCs) and TCZ notably increases the risk of infections. When TCZ is used, careful attention must be paid to possible infections, and dose of GC should be tapered as much as possible. Future tasks are to establish indication and dosage of TCZ, indication for discontinuation of TCZ due to remission, efficacy of TCZ monotherapy, and protocols of TCZ for pediatric cases.

Development of an evidence-based regimen of prednisolone to treat giant cell arteritis - the Norwich regimen

We have reviewed the literature to form a bespoke regimen for daily oral prednisolone (DP) in GCA. Initial DP in clinical trials is 40-60 mg daily, but relapse rates are 67-92%. Cumulative prednisolone (CP) of 3.2 and 3.9 g (at 6 months) resulted in a relapse rate of 83 and 67%, respectively; and 3 and 3.9 g (at 12 months) resulted in 92 and 82% relapse, respectively. CP was 6.2-7.1 g in the first year. Mean DP was 18.8 mg at 3 months and 6.6-7.4 mg at 12 months. The duration of treatment with prednisolone for GCA was 22-26 months. The CP to achieve discontinuation was 6.5-12.1 g. Using these data, the Norwich regimen starts DP at 1 mg/kg/day of lean body mass, discontinuing over 100 weeks. For the average UK woman, initial DP is 45 mg daily, reaching 21 mg daily by 12 weeks and 6 mg daily by 52 weeks. The CP for the average UK woman would be 6.5 g at 52 weeks and 7.4 g to discontinuation.

The Treatment of Giant Cell Arteritis in Different Clinical Settings

This paper aims to raise awareness of the different disease courses, comorbidities, and therapy situations in patients with giant cell arteritis (GCA), which require a differentiated approach and often a deviation from current treatment guidelines. With the approval of tocilizumab (TOC), which specifically binds to both soluble and membrane-bound IL-6 receptor and inhibits IL-6 receptor-mediated signaling, the spectrum of available effective treatment options has been significantly broadened. TOC yields an extensive range of possible applications that go beyond a glucocorticoid-saving effect. In this context, the treatment of GCA is dependent on the disease course as well as the associated comorbidities. The different stages of GCA in association to co-morbidities require a detailed treatment strategy.

Giant cell arteritis: early diagnosis is key

Giant cell arteritis (GCA) is an inflammatory vasculitis typically affecting elderly that can potentially cause vision loss. Studies have demonstrated that early recognition and initiation of treatment can improve visual prognosis in patients with GCA. This review addresses the benefits of early diagnosis and treatment, and discusses the available treatment options to manage the disease.

Cardiovascular toxicities associated with immune checkpoint inhibitors: an observational, retrospective, pharmacovigilance study

BACKGROUND

Immune checkpoint inhibitors (ICIs) have substantially improved clinical outcomes in multiple cancer types and are increasingly being used in early disease settings and in combinations of different immunotherapies. However, ICIs can also cause severe or fatal immune-related adverse-events (irAEs). We aimed to identify and characterise cardiovascular irAEs that are significantly associated with ICIs.

METHODS

In this observational, retrospective, pharmacovigilance study, we used VigiBase, WHO's global database of individual case safety reports, to compare cardiovascular adverse event reporting in patients who received ICIs (ICI subgroup) with this reporting in the full database. This study included all cardiovascular irAEs classified by group queries according to the Medical Dictionary for Regulatory Activities, between inception on Nov 14, 1967, and Jan 2, 2018. We evaluated the association between ICIs and cardiovascular adverse events using the reporting odds ratio (ROR) and the information component (IC). IC is an indicator value for disproportionate Bayesian reporting that compares observed and expected values to find associations between drugs and adverse events. IC₀₂₅ is the lower end of the IC 95% credibility interval, and an IC₀₂₅ value of more than zero is deemed significant. This study is registered with ClinicalTrials.gov, number NCT03387540.

FINDINGS

We identified 31 321 adverse events reported in patients who received ICIs and 16 343 451 adverse events reported in patients treated with any drugs (full database) in VigiBase. Compared with the full database, ICI treatment was associated with higher reporting of myocarditis (5515 reports for the full database vs 122 for ICIs, ROR 11·21 [95% CI 9·36-13·43]; IC₀₂₅ 3·20), pericardial diseases (12 800 vs 95, 3·80 [3·08-4·62]; IC₀₂₅ 1·63), and vasculitis (33 289 vs 82, 1·56 [1·25-1·94]; IC₀₂₅ 0·03), including temporal arteritis (696 vs 18, 12·99 [8·12-20·77]; IC₀₂₅ 2·59) and polymyalgia rheumatica (1709 vs 16, 5·13 [3·13-8·40]; IC₀₂₅ 1·33). Pericardial diseases were reported more often in patients with lung cancer (49 [56%] of 87 patients), whereas myocarditis (42 [41%] of 103 patients) and vasculitis (42 [60%] of 70 patients) were more commonly reported in patients with melanoma (χ² test for overall subgroup comparison, p<0·0001). Vision was impaired in five (28%) of 18 patients with temporal arteritis. Cardiovascular irAEs were severe in the majority of cases (>80%), with death occurring in 61 (50%) of 122 myocarditis cases, 20 (21%) of 95 pericardial disease cases, and five (6%) of 82 vasculitis cases (χ² test for overall comparison between pericardial diseases, myocarditis, and vasculitis, p<0·0001).

INTERPRETATION

Treatment with ICIs can lead to severe and disabling inflammatory cardiovascular irAEs soon after commencement of therapy. In addition to life-threatening myocarditis, these toxicities include pericardial diseases and temporal arteritis with a risk of blindness. These events should be considered in patient care and in combination clinical trial designs (ie, combinations of different immunotherapies as well as immunotherapies and chemotherapy).

FUNDING

The Cancer Institut Thématique Multi-Organisme of the French National Alliance for Life and Health Sciences (AVIESAN) Plan Cancer 2014-2019; US National Cancer Institute, National Institutes of Health; the James C. Bradford Jr. Melanoma Fund; and the Melanoma Research Foundation.

Cardiovascular toxicities associated with immune checkpoint inhibitors: an observational, retrospective, pharmacovigilance study

BACKGROUND

Immune checkpoint inhibitors (ICIs) have substantially improved clinical outcomes in multiple cancer types and are increasingly being used in early disease settings and in combinations of different immunotherapies. However, ICIs can also cause severe or fatal immune-related adverse-events (irAEs). We aimed to identify and characterise cardiovascular irAEs that are significantly associated with ICIs.

METHODS

In this observational, retrospective, pharmacovigilance study, we used VigiBase, WHO's global database of individual case safety reports, to compare cardiovascular adverse event reporting in patients who received ICIs (ICI subgroup) with this reporting in the full database. This study included all cardiovascular irAEs classified by group queries according to the Medical Dictionary for Regulatory Activities, between inception on Nov 14, 1967, and Jan 2, 2018. We evaluated the association between ICIs and cardiovascular adverse events using the reporting odds ratio (ROR) and the information component (IC). IC is an indicator value for disproportionate Bayesian reporting that compares observed and expected values to find associations between drugs and adverse events. IC₀₂₅ is the lower end of the IC 95% credibility interval, and an IC₀₂₅ value of more than zero is deemed significant. This study is registered with ClinicalTrials.gov, number NCT03387540.

FINDINGS

We identified 31 321 adverse events reported in patients who received ICIs and 16 343 451 adverse events reported in patients treated with any drugs (full database) in VigiBase. Compared with the full database, ICI treatment was associated with higher reporting of myocarditis (5515 reports for the full database vs 122 for ICIs, ROR 11·21 [95% CI 9·36-13·43]; IC₀₂₅ 3·20), pericardial diseases (12 800 vs 95, 3·80 [3·08-4·62]; IC₀₂₅ 1·63), and vasculitis (33 289 vs 82, 1·56 [1·25-1·94]; IC₀₂₅ 0·03), including temporal arteritis (696 vs 18, 12·99 [8·12-20·77]; IC₀₂₅ 2·59) and polymyalgia rheumatica (1709 vs 16, 5·13 [3·13-8·40]; IC₀₂₅ 1·33). Pericardial diseases were reported more often in patients with lung cancer (49 [56%] of 87 patients), whereas myocarditis (42 [41%] of 103 patients) and vasculitis (42 [60%] of 70 patients) were more commonly reported in patients with melanoma (χ² test for overall subgroup comparison, p<0·0001). Vision was impaired in five (28%) of 18 patients with temporal arteritis. Cardiovascular irAEs were severe in the majority of cases (>80%), with death occurring in 61 (50%) of 122 myocarditis cases, 20 (21%) of 95 pericardial disease cases, and five (6%) of 82 vasculitis cases (χ² test for overall comparison between pericardial diseases, myocarditis, and vasculitis, p<0·0001).

INTERPRETATION

Treatment with ICIs can lead to severe and disabling inflammatory cardiovascular irAEs soon after commencement of therapy. In addition to life-threatening myocarditis, these toxicities include pericardial diseases and temporal arteritis with a risk of blindness. These events should be considered in patient care and in combination clinical trial designs (ie, combinations of different immunotherapies as well as immunotherapies and chemotherapy).

FUNDING

The Cancer Institut Thématique Multi-Organisme of the French National Alliance for Life and Health Sciences (AVIESAN) Plan Cancer 2014-2019; US National Cancer Institute, National Institutes of Health; the James C. Bradford Jr. Melanoma Fund; and the Melanoma Research Foundation.

Pathogenesis of large vessel vasculitis: Implications for disease classification and future therapies

Despite being recognised over a century ago, the aetiology and pathogenesis of large vessel vasculitis (LVV) still remains elusive. Takayasu’s arteritis (TA) and giant cell arteritis (GCA) represent the two major categories of LVV, each with distinctive clinical features. Over the last 10 years an increased understanding of the immunopathogenesis of the inflammatory cascade within the aortic wall has revived the view that LVVs may represent subtypes of the same pathological process, with implications in the treatment of this disease. In this review, the histological, genetic and immunopathological features of TA and GCA will be discussed and the evidence for a common underlying disease mechanism examined. Novel markers of disease activity and therapies based on advances in our understanding of the immunopathogenesis of these conditions will also be discussed.

Diagnosis and differential diagnosis of large-vessel vasculitides

There are no universally accepted diagnostic criteria for large-vessel vasculitides (LVV), including giant cell arteritis (GCA) and Takayasu arteritis (TAK). Currently, available classification criteria cannot be used for the diagnosis of GCA and TAK. Early diagnosis of these two diseases is quite challenging in clinical practice and may be accomplished only by combining the patient symptoms, physical examination findings, blood test results, imaging findings, and biopsy results, if available. Awareness of red flags which lead the clinician to investigate TAK in a young patient with persistent systemic inflammation is helpful for the early diagnosis. It should be noted that clinical presentation may be highly variable in a subgroup of GCA patients with predominant large-vessel involvement (LVI) and without prominent cranial symptoms. Imaging modalities are especially helpful for the diagnosis of this subgroup. Differential diagnosis between older patients with TAK and this subgroup of GCA patients presenting with LVI may be difficult. Various pathologies may mimic LVV either by causing systemic inflammation and constitutional symptoms, or by causing lumen narrowing with or without aneurysm formation in the aorta and its branches. Differential diagnosis of aortitis is crucial. Infectious aortitis including mycotic aneurysms due to septicemia or endocarditis, as well as causes such as syphilis and mycobacterial infections should always be excluded. On the other hand, the presence of non-infectious aortitis is not unique for TAK and GCA. It should be noted that aortitis, other large-vessel involvement or both, may occasionally be seen in various other autoimmune pathologies including ANCA-positive vasculitides, Behçet's disease, ankylosing spondylitis, sarcoidosis, and Sjögren's syndrome. Besides, aortitis may be idiopathic and isolated. Atherosclerosis should always be considered in the differential diagnosis of LVV. Other pathologies which may mimic LVV include, but not limited to, congenital causes of aortic coarctation and middle aortic syndrome, immunoglobulin G4-related disease, and hereditary disorders of connective tissue such as Marfan syndrome and Ehler-Danlos syndrome.

Current and emerging therapies in large-vessel vasculitis

GCA shares many clinical features with PMR and Takayasu arteritis. The current mainstay of therapy for all three conditions is glucocorticoid therapy. Given the chronic, relapsing nature of these conditions and the morbidity associated with glucocorticoid therapy, there is a need for better treatment options to induce and sustain remission with fewer adverse effects. Conventional immunosuppressive treatments have been studied and have a modest effect. There is a keen interest in biologic therapies with studies showing the efficacy of IL-6 antagonists in PMR and GCA. Recently the first two randomized clinical trials in Takayasu arteritis have been completed. A major challenge for all of these conditions is the lack of standardized measures to assess disease activity. Long-term studies are needed to evaluate the impact of biologic therapies showing potential on important clinical outcomes such as vascular damage, cost-effectiveness and quality of life. The optimal duration of treatment also needs to be assessed.

Prevention of glucocorticoid morbidity in giant cell arteritis

Glucocorticoids are the mainstay of treatment for GCA. Patients often require long-term treatment that may be associated with numerous adverse effects, depending on the dose and the duration of treatment. Trends in recent decades for glucocorticoid use in GCA suggest increasing cumulative doses and longer exposures. Common adverse events (AEs) reported in glucocorticoid-treated GCA patients include osteoporosis, hypercholesterolaemia, hypertension, posterior subcapsular cataract, infections, diabetes mellitus, Cushingoid appearance, adrenal insufficiency and aseptic necrosis of bone. AEs considered most worrisome by patients and rheumatologists include weight gain, psychological effects, osteoporosis, cardiometabolic complications and infections. The challenge is to maximize the benefit-risk ratio by giving the maximum glucocorticoid treatment necessary to control GCA initially and then to prevent relapse but to give the minimum treatment possible to avoid glucocorticoid-related AEs. We discuss the safety issues associated with long-term glucocorticoid use in patients with GCA and strategies for preventing glucocorticoid-related morbidity.

Giant cell arteritis: beyond temporal artery biopsy and steroids

Giant cell arteritis is the most common primary vasculitis of the elderly. The acute complications of untreated giant cell arteritis, such as vision loss or occasionally stroke, can be devastating. The diagnosis is, however, not altogether straightforward due to variable sensitivities of the temporal artery biopsy as a reference diagnostic test. In this review, we discuss the increasing role of imaging in the diagnosis of giant cell arteritis. Glucocorticoid treatment is the backbone of therapy, but it is associated with significant adverse effects. A less toxic alternative is required. Conventional and novel immunosuppressive agents have only demonstrated modest effects in a subgroup of steroid refractory Giant cell arteritis due to the different arms of the immune system at play. However, recently a study of interleukin-6 blockade demonstrated benefits of giant cell arteritis. The current status of these immunosuppressive agents and novel therapies are also discussed in this review.

Current treatment options for psoriatic arthritis: spotlight on abatacept

Psoriatic arthritis (PsA) is a chronic inflammatory disease of joints, tendon sheaths, and entheses affecting patients with established skin psoriasis, or, less frequently, patients without a personal history of psoriasis with a positive familial history. Many treatment options are now available to deal with the different aspects of the disease, including traditional and biological disease-modifying antirheumatic drugs and the recently released targeted synthetic disease-modifying antirheumatic drugs. However, ~40% of patients still fail to achieve a meaningful clinical response to first-line biologic therapy advocating the development of novel medications. It is now well accepted that T-cells participate in the immunopathogenesis of several autoimmune diseases. For this reason, the potential intervention on T-cells represented an attractive therapeutic target for a long time, becoming a clinical reality with the development of abatacept. Abatacept is a biologic agent selectively targeting the T-cell costimulatory signal delivered through the CD80/86-CD28 pathway and was approved in December 2005 by the US Food and Drug Administration and in May 2007 by European Medicines Agency for the treatment of patients with rheumatoid arthritis in combination with methotrexate. Based on the relevant role of T-cells in PsA pathogenesis and following the positive results obtained in a phase III clinical trial, abatacept recently received approval for treatment of patients with PsA. In this review, we will focus on the current knowledge about the emerging role of abatacept in treatment of PsA.

Arterial lesions in giant cell arteritis: A longitudinal study

OBJECTIVES

To evaluate large-vessel (LV) abnormalities on serial imaging in patients with giant cell arteritis (GCA) and discern predictors of new lesions.

METHODS

Clinical and imaging data from patients with GCA (including subjects diagnosed by LV imaging) enrolled in a prospective, multicenter, longitudinal study and/or a randomized clinical trial were included. New arterial lesions were defined as a lesion in a previously unaffected artery.

RESULTS

The study included 187 patients with GCA, 146 (78%) female, mean (±SD) age at diagnosis 68.5 ± 8.5 years; 39% diagnosed by LV imaging. At least one arterial lesion was present in 123 (66%) on the first study. The most frequently affected arteries were subclavian (42%), axillary (32%), and thoracic aorta (20%). In 106 patients (57%) with serial imaging, new arterial lesions were noted in 41 patients (39%), all of whom had a baseline abnormality, over a mean (±SD) follow-up of 4.39 (2.22) years. New abnormalities were observed in 33% patients by year 2; clinical features of active disease were present at only 50% of these cases. There were no differences in age, sex, temporal artery biopsy positivity, or disease activity in patients with or without new lesions.

CONCLUSIONS

In this cohort of patients with GCA, LV abnormalities on first imaging were common. Development of new arterial lesions occurred in patients with arterial abnormalities at first imaging, often in the absence of symptoms of active disease. Arterial imaging should be considered in all patients with GCA at diagnosis and serial imaging at least in patients with baseline abnormalities.

Expression and Function of IL12/23 Related Cytokine Subunits (p35, p40, and p19) in Giant-Cell Arteritis Lesions: Contribution of p40 to Th1- and Th17-Mediated Inflammatory Pathways

Background

Giant-cell arteritis (GCA) is considered a T helper (Th)1- and Th17-mediated disease. Interleukin (IL)-12 is a heterodimeric cytokine (p35/p40) involved in Th1 differentiation. When combining with p19 subunit, p40 compose IL-23, a powerful pro-inflammatory cytokine that maintains Th17 response.

Objectives

The aims of this study were to investigate p40, p35, and p19 subunit expression in GCA lesions and their combinations to conform different cytokines, to assess the effect of glucocorticoid treatment on subunit expression, and to explore functional roles of p40 by culturing temporal artery sections with a neutralizing anti-human IL-12/IL-23p40 antibody.

Methods and results

p40 and p19 mRNA concentrations measured by real-time RT-PCR were significantly higher in temporal arteries from 50 patients compared to 20 controls (4.35 ± 4.06 vs 0.51 ± 0.75; p < 0.0001 and 20.32 ± 21.78 vs 4.17 ± 4.43 relative units; p < 0.0001, respectively). No differences were found in constitutively expressed p35 mRNA. Contrarily, p40 and p19 mRNAs were decreased in temporal arteries from 16 treated GCA patients vs those from 34 treatment-naïve GCA patients. Accordingly, dexamethasone reduced p40 and p19 expression in cultured arteries. Subunit associations to conform IL-12 and IL-23 were confirmed by proximity-ligation assay in GCA lesions. Immunofluorescence revealed widespread p19 and p35 expression by inflammatory cells, independent from p40. Blocking IL-12/IL-23p40 tended to reduce IFNγ and IL-17 mRNA production by cultured GCA arteries and tended to increase Th17 inducers IL-1β and IL-6.

Conclusion

IL-12 and IL-23 heterodimers are increased in GCA lesions and decrease with glucocorticoid treatment. p19 and p35 subunits are much more abundant than p40, indicating an independent role for these subunits or their potential association with alternative subunits. The modest effect of IL-12/IL-23p40 neutralization may indicate compensation by redundant cytokines or cytokines resulting from alternative combinations.

Comparison of magnetic resonance angiography and 18F-fluorodeoxyglucose positron emission tomography in large-vessel vasculitis

OBJECTIVES

To assess agreement between interpretation of magnetic resonance angiography (MRA) and ¹⁸F-fluorodeoxyglucose positron emission tomography (PET) for disease extent and disease activity in large-vessel vasculitis (LVV) and determine associations between imaging and clinical assessments.

METHODS

Patients with giant cell arteritis (GCA), Takayasu's arteritis (TAK) and comparators were recruited into a prospective, observational cohort. Imaging and clinical assessments were performed concurrently, blinded to each other. Agreement was assessed by per cent agreement, Cohen's kappa and McNemar's test. Multivariable logistic regression identified MRA features associated with PET scan activity.

RESULTS

Eighty-four patients (GCA=35; TAK=30; comparator=19) contributed 133 paired studies. Agreement for disease extent between MRA and PET was 580 out of 966 (60%) arterial territories with Cohen's kappa=0.22. Of 386 territories with disagreement, MRA demonstrated disease in more territories than PET (304vs82, p<0.01). Agreement for disease activity between MRA and PET was 90 studies (68%) with Cohen's kappa=0.30. In studies with disagreement, MRA demonstrated activity in 23 studies and PET in 20 studies (p=0.76). Oedema and wall thickness on MRA were independently associated with PET scan activity. Clinical status was associated with disease activity by PET (p<0.01) but not MRA (p=0.70), yet 35/69 (51%) patients with LVV in clinical remission had active disease by both MRA and PET.

CONCLUSIONS

In assessment of LVV, MRA and PET contribute unique and complementary information. MRA better captures disease extent, and PET scan is better suited to assess vascular activity. Clinical and imaging-based assessments often do not correlate over the disease course in LVV.

TRIAL REGISTRATION NUMBER

NCT02257866.

Diagnosis and management of giant cell arteritis: an Asia-Pacific perspective

Giant cell arteritis is the commonest primary vasculitis of the elderly. However, the prevalence does vary widely between populations with highest incidence amongst Northern Europeans and lowest amongst East Asians. Preliminary studies suggest that clinical manifestations may differ between different populations. Newer diagnostic approaches including ultrasound, MR angiography and PET imaging are under review. While there have been recent advances in the diagnosis of GCA particularly with regard to imaging, there is an urgent need for improvements in methods of diagnosis, treatment and requirement for screening. Glucocorticoid treatment remain the backbone of therapy. However, glucocorticoid therapy is associated with significant adverse effects. Conventional and novel immunosuppressive agents have only demonstrated modest effects in a subgroup of steroid refractory GCA due to the different arms of the immune system at play. However, recently a study of IL-6 blockade demonstrated benefit in GCA. Newer approaches such as fast-track pathways can also result in improvements in consequences of GCA including blindness.

FDG-PET/CT(A) imaging in large vessel vasculitis and polymyalgia rheumatica: joint procedural recommendation of the EANM, SNMMI, and the PET Interest Group (PIG), and endorsed by the ASNC

Large vessel vasculitis (LVV) is defined as a disease mainly affecting the large arteries, with two major variants, Takayasu arteritis (TA) and giant cell arteritis (GCA). GCA often coexists with polymyalgia rheumatica (PMR) in the same patient, since both belong to the same disease spectrum. FDG-PET/CT is a functional imaging technique which is an established tool in oncology, and has also demonstrated a role in the field of inflammatory diseases. Functional FDG-PET combined with anatomical CT angiography, FDG-PET/CT(A), may be of synergistic value for optimal diagnosis, monitoring of disease activity, and evaluating damage progression in LVV. There are currently no guidelines regarding PET imaging acquisition for LVV and PMR, even though standardization is of the utmost importance in order to facilitate clinical studies and for daily clinical practice. This work constitutes a joint procedural recommendation on FDG-PET/CT(A) imaging in large vessel vasculitis (LVV) and PMR from the Cardiovascular and Inflammation & Infection Committees of the European Association of Nuclear Medicine (EANM), the Cardiovascular Council of the Society of Nuclear Medicine and Molecular Imaging (SNMMI), and the PET Interest Group (PIG), and endorsed by the American Society of Nuclear Cardiology (ASNC). The aim of this joint paper is to provide recommendations and statements, based on the available evidence in the literature and consensus of experts in the field, for patient preparation, and FDG-PET/CT(A) acquisition and interpretation for the diagnosis and follow-up of patients with suspected or diagnosed LVV and/or PMR. This position paper aims to set an internationally accepted standard for FDG-PET/CT(A) imaging and reporting of LVV and PMR.

Takayasu arteritis and giant cell arteritis: are they a spectrum of the same disease?

Giant cell arteritis (GCA) and Takayasu arteritis (TAK) are forms of large-vessel vasculitides that affect the aorta and its branches. There is ongoing debate about whether they are within a spectrum of the same disease or different diseases. Shared commonalities include clinical features, evidence of systemic inflammation, granulomatous inflammation on biopsy, role of T-helper (Th)-1 and Th17 in the pathogenesis, and, abnormalities of the aorta and its branches on imaging. However, there are also several differences in the geographic distribution, genetics, inflammatory cells and responses to treatment. This review highlights the similarities and differences in the epidemiology, pathogenesis, clinical manifestations, imaging findings and treatment responses in these conditions. Current data supports that they are two distinct conditions despite the numerous similarities.

Recent Advances in Giant Cell Arteritis

PURPOSE OF REVIEW

Giant cell arteritis (GCA) is the most common systemic vasculitis. GCA is categorized as a granulomatous vasculitis of large and medium size vessels. Majority of the symptoms and signs of GCA result from involvement of the aorta and its branches intra- and extracranial. Temporal artery biopsy continues to be the cardinal diagnostic procedure despite new imaging modalities for diagnosing GCA with cranial involvement. Great advances in awareness have led to improvement in preventing irreversible vision loss due to early diagnosis.

RECENT FINDINGS

The cause of GCA has not been elucidated but major progress has been made in the knowledge of its pathogenesis leading to new therapeutic targets, particularly inhibition of interleukin 6. IL 6 plays a key role in the regulation of TH17/Tregs imbalance in GCA and appears to correlate with clinical disease activity in GCA. All of this has led to the first FDA (food and drug administration) approved treatment for GCA, Tocilizumab. Abatacept and Ustekinumab are promising targets for therapy in LVV but still need further research. This paper is a review of the recent progress in the understanding of GCA pathogenesis, diagnosis, treatment, and prognosis.

Biological treatments in giant cell arteritis & Takayasu arteritis

Giant cell arteritis (GCA) and Takayasu arteritis (TAK) are the two main large vessel vasculitides. They share some similarities regarding their clinical, radiological and histological presentations but some pathogenic processes in GCA and TAK are activated differently, thus explaining their different sensitivity to biological therapies. The treatment of GCA and TAK essentially relies on glucocorticoids. However, thanks to major progress in our understanding of their pathogenesis, the role of biological therapies in the treatment of these two vasculitides is expanding, especially in relapsing or refractory diseases. In this review, the efficacy, the safety and the limits of the main biological therapies ever tested in GCA and TAK are discussed. Briefly, anti TNF-α agents appear to be effective in treating TAK but not GCA. Recent randomized placebo-controlled trials have reported on the efficacy and safety of abatacept and mostly tocilizumab in inducing and maintaining remission of GCA. Abatacept was not effective in TAK and robust data are still lacking to draw any conclusions concerning the use of tocilizumab in TAK. Furthermore, ustekinumab appears promising in relapsing/refractory GCA whereas rituximab has been reported to be effective in only a few cases of refractory TAK patients. If a biological therapy is indicated, and in light of the data discussed in this review, the first choice would be tocilizumab in GCA and anti-TNF-α agents (mainly infliximab) in TAK.

Checks and Balances in Autoimmune Vasculitis

Age-associated changes in the immune system including alterations in surface protein expression are thought to contribute to an increased susceptibility for autoimmune diseases. The balance between the expression of coinhibitory and costimulatory surface protein molecules, also known as immune checkpoint molecules, is crucial in fine-tuning the immune response and preventing autoimmunity. The activation of specific inhibitory signaling pathways allows cancer cells to evade recognition and destruction by the host immune system. The use of immune checkpoint inhibitors (ICIs) to treat cancer has proven to be effective producing durable antitumor responses in multiple cancer types. However, one of the disadvantages derived from the use of these agents is the appearance of inflammatory manifestations termed immune-related adverse events (irAEs). These irAEs are often relatively mild, but more severe irAEs have been reported as well including several forms of vasculitis. In this article, we argue that age-related changes in expression and function of immune checkpoint molecules lead to an unstable immune system, which is prone to tolerance failure and autoimmune vasculitis development. The topic is introduced by a case report from our hospital describing a melanoma patient treated with ICIs and who subsequently developed biopsy-proven giant cell arteritis. Following this case report, we present an in-depth review on the role of immune checkpoint pathways in the development and progression of autoimmune vasculitis and its relation with an aging immune system.

Profile of tocilizumab and its potential in the treatment of giant cell arteritis

Giant cell arteritis (GCA) remains a medical emergency due to the threat of permanent sight loss. High-dose glucocorticoids (GCs) are effective in inducing remission in the majority of patients, however, relapses are common which lengthen GC therapy. GC toxicity remains a major morbidity in this group of patients, and conventional steroid-sparing therapies have not yet shown enough of a clinical benefit to change the standard of care. As the understanding of the underlying immunopathophysiology of GCA has increased, positive clinical observations have been made with the use of IL-6 receptor inhibitor therapies, such as tocilizumab (TCZ). This has led to prospective randomized control trials that have highlighted the safety and efficacy of TCZ in both new-onset and relapsing GCA.

Giant Cell Arteritis: Practical Pearls and Updates

PURPOSE OF REVIEW

The purpose of this review is to summarize recent updates and distill practical points from the literature which can be applied to the care of patients with suspected and confirmed giant cell arteritis (GCA).

RECENT FINDINGS

Contemporary thinking implicates a fundamental failure of T regulatory cell function in GCA pathophysiology, representing opportunity for novel therapeutic avenues. Tocilizumab has become the first Food and Drug Administration-approved treatment for GCA following demonstration of efficacy and safety in a phase 3 clinical trial. There have been significant parallel advances in both our understanding of GCA pathophysiology and treatment. Tocilizumab, and other agents currently under investigation in phase 2 and 3 clinical trials, presents a new horizon of hope for both disease remission and avoidance of glucocorticoid-related complications.

Treatments for giant cell arteritis: Meta-analysis and assessment of estimates reliability using the fragility index

BACKGROUND

To better communicate the results of randomized controlled trials (RCTs) of giant cell arteritis (GCA), we propose the use of the fragility index (FI), which is an intuitive measure defined as the minimum number of subjects whose status would have to change (e.g., from having the outcome to not) to render a statistically significant result nonsignificant, or vice-versa.

METHODS

We conducted a systematic review and random-effects meta-analysis of RCTs of glucocorticoid (GC) sparing strategies for relapse-free maintenance in GCA, and used the FI to simplify the presentation of results.

RESULTS

Ten RCTs (nine phase II and one phase III enrolling 645 subjects) were included. Tocilizumab, IV GC and methotrexate significantly improved the likelihood of being relapse free with relative risks and 95% confidence intervals of 3.54 (2.28, 5.51), 5.11 (1.39, 18.81) and 1.54 (1.02, 2.30); respectively. The median FI was 4.5 (range, 1-28), and was generally higher for negative RCTs (n = 6; median FI 4.5) than for positive RCTs (n = 4; median FI 3.5). The range of FI per treatment was (1-8) for methotrexate, (2-6) for anti-TNF agents, 4 for abatacept, 3 for IV GC pulses and (4-28) for tocilizumab.

CONCLUSION

Tocilizumab, IV GC and methotrexate improve the likelihood of being relapse-free in subjects with GCA. Assessment of GC sparing strategies in GCA has long depended on imprecise trials that would change significance if outcomes were reversed for a handful of subjects. FI may be used in rheumatology to simplify communication of statistical significance and overcome limitations of p-value.

Serum osteopontin: a biomarker of disease activity and predictor of relapsing course in patients with giant cell arteritis. Potential clinical usefulness in tocilizumab-treated patients

Background

Osteopontin (OPN) is a glycoprotein involved in Th1 and Th17 differentiation, tissue inflammation and remodelling. We explored the role of serum OPN (sOPN) as a biomarker in patients with giant cell arteritis (GCA).

Methods

sOPN was measured by immunoassay in 76 treatment-naïve patients with GCA and 25 age-matched and sex-matched controls. In 36 patients, a second measurement was performed after 1 year of glucocorticoid treatment. Baseline clinical and laboratory findings, as well as relapses and glucocorticoid requirements during follow-up, were prospectively recorded. sOPN and C reactive protein (CRP) were measured in 32 additional patients in remission treated with glucocorticoids or tocilizumab (interleukin 6 (IL-6) receptor antagonist). In cultured temporal arteries exposed and unexposed to tocilizumab, OPN mRNA expression and protein production were measured by reverse transcription polymerase chain reaction (RT-PCR) and immunoassay, respectively.

Results

sOPN concentration (ng/mL; mean±SD) was significantly elevated in patients with active disease (116.75±65.61) compared with controls (41.10±22.65; p<0.001). A significant decline in sOPN was observed in paired samples as patients entered disease remission (active disease 102.45±57.72, remission 46.47±23.49; p<0.001). sOPN correlated with serum IL-6 (r=0.55; p<0.001). Baseline sOPN concentrations were significantly higher in relapsing versus non-relapsing patients (relapsers 129.08±74.24, non-relapsers 90.63±41.02; p=0.03). OPN mRNA expression and protein production in cultured arteries were not significantly modified by tocilizumab. In tocilizumab-treated patients, CRP became undetectable, whereas sOPN was similar in patients in tocilizumab-maintained (51.91±36.25) or glucocorticoid-maintained remission (50.65±23.59; p=0.49).

Conclusions

sOPN is a marker of disease activity and a predictor of relapse in GCA. Since OPN is not exclusively IL-6-dependent, sOPN might be a suitable disease activity biomarker in tocilizumab-treated patients.

Giant cell arteritis: pathogenic mechanisms and new potential therapeutic targets

Giant cell arteritis (GCA) is the most common idiopathic systemic vasculitis in persons aged 50 years or greater. Treatment options for GCA, to-date, have been limited and have consisted primarily of glucocorticoids. Significant advances in the understanding of the genetic and cellular mechanisms in GCA are leading to identification of potential pathogenic targets. The recent success of interleukin-6 blockade in the treatment of GCA has opened the landscape to targeted biologic therapy. T cells, particularly T helper 1 and T helper 17 cell lineages have been identified as key inflammatory cells in both active and chronic vascular inflammatory lesions. Therapeutic agents, including abatacept and ustekinumab, which can impede both vasculitogenic cell lines are of particular interest. Inhibition of signalling pathways, including the janus kinase-signal tranducers and activation of transcription (JAK-STAT) and Notch pathways are evolving options. Tocilizumab has shown clear benefit in both newly diagnosed and relapsing patients with GCA and approval of this medication for treatment of GCA has led to rapid incorporation into treatment regimens. More information is required to understand the long-term outcomes of tocilizumab and other investigational targeted therapeutics in the treatment of GCA.

Long-term glucocorticoid treatment in patients with polymyalgia rheumatica, giant cell arteritis, or both diseases: results from a national rheumatology database

The objective of this study was to evaluate glucocorticoid (GC) use in patients with polymyalgia rheumatica (PMR), giant cell arteritis (GCA) or both diseases (PMR + GCA) under rheumatological care. Data from patients with PMR (n = 1420), GCA (n = 177) or PMR + GCA (n = 261) from the National Database of the German Collaborative Arthritis Centers were analyzed regarding GCs and related comorbidities (osteoporosis, diabetes and cardiovascular disease), stratified by disease duration (DD). Longitudinal data were analyzed for all patients with a DD ≤ 2 years at database entry (n = 1397). Three-year data were available for 256 patients. Predictors of GC use ≥ 3 years were examined by logistic regression analyses. A total of 76% received GCs, and 19% (PMR) to 40% (GCA) received methotrexate. Median GC doses were 12.5 mg (PMR), 11.3 mg (GCA), and 20.0 mg/day (PMR + GCA) in a 0-6-month DD. Median GC doses ≤ 5 mg/day were reached at a 13-18-month DD in PMR patients and at a 19-24-month DD in GCA or PMR + GCA patients. In the multivariate analysis, baseline methotrexate (OR 2.03, [95% CI 1.27-3.24]), GCs > 10 mg/day (OR 1.65, [1.07-2.55]), higher disease activity (OR 1.12, [1.02-1.23]) (median 0.6 years DD), and female sex (OR 1.63 [1.09-2.43]) were predictive for GC therapy at ≥ 3 years. Of the examined comorbidities, only osteoporosis prevalence increased within 3 years. GC use for ≥ 3 years was reported in one-fourth of all the patients. A difficult-to-control disease activity within the first year was a good predictor of long-term GC need.

Polymyalgia rheumatica development in a patient under PI3K inhibitor therapy for chronic lymphocytic leukaemia

We report a patient with chronic lymphocytic leukaemia (CLL) who was treated with idelalisib, a PI3Kδ inhibitor with rituximab. After 20 weeks of treatment, the patient developed classical signs and symptoms of polymyalgia rheumatica (PMR) in association with an elevated C reactive protein of 74 mg/L. After 2 weeks of prednisolone 15 mg daily symptoms had resolved and acute phase markers normalised. To our knowledge, this is the first report of PMR developing as a complication of PI3Kδ inhibitor treatment of CLL.

Polymyalgia rheumatica

Polymyalgia rheumatica is an inflammatory disease that affects the shoulder, the pelvic girdles, and the neck, usually in individuals older than 50 years. Increases in acute phase reactants are typical of polymyalgia rheumatica. The disorder might present as an isolated condition or in association with giant cell arteritis. Several diseases, including inflammatory rheumatic and autoimmune diseases, infections, and malignancies can mimic polymyalgia rheumatica. Imaging techniques have identified the presence of bursitis in more than half of patients with active disease. Vascular uptake on PET scans is seen in some patients. A dose of 12·5-25·0 mg prednisolone daily or equivalent leads to rapid improvement of symptoms in most patients with isolated disease. However, relapses are common when prednisolone is tapered. Methotrexate might be used in patients who relapse. The effectiveness of biological therapies, such as anti-interleukin 6, in patients with polymyalgia rheumatica that is refractory to glucocorticoids requires further investigation. Most population-based studies indicate that mortality is not increased in patients with isolated disease.

The European Vasculitis Society 2016 Meeting Report

The 2016 European Vasculitis Society (EUVAS) meeting, held in Leiden, the Netherlands, was centered around phenotypic subtyping in antineutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV). There were parallel meetings of the EUVAS petals, which here report on disease assessment; database; and long-term follow-up, registries, genetics, histology, biomarker studies, and clinical trials. Studies currently conducted will improve our ability to discriminate between different forms of vasculitis. In a project that involves the 10-year follow-up of AAV patients, we are working on retrieving data on patient and renal survival, relapse rate, the cumulative incidence of malignancies, and comorbidities. Across Europe, several vasculitis registries were developed covering over 10,000 registered patients. In the near future, these registries will facilitate clinical research in AAV on a scale hitherto unknown. Current studies on the genetic background of AAV will explore the potential prognostic significance of genetic markers and further refine genetic associations with distinct disease subsets. The histopathological classification of ANCA-associated glomerulonephritis is currently evaluated in light of data coming out of a large international validation study. In our continuous search for biomarkers to predict clinical outcome, promising new markers are important subjects of current research. Over the last 2 decades, a host of clinical trials have provided evidence for refinement of therapeutic regimens. We give an overview of clinical trials currently under development, and consider refractory vasculitis in detail. The goal of EUVAS is to stimulate ongoing research in clinical, serological, and histological management and techniques for patients with systemic vasculitis, with an outlook on the applicability for clinical trials.

Giant cell arteritis and polymyalgia rheumatica: current challenges and opportunities

The fields of giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) have advanced rapidly, resulting in a new understanding of these diseases. Fast-track strategies and improved awareness programmes that prevent irreversible sight loss through early diagnosis and treatment are a notable advance. Ultrasonography and other imaging techniques have been introduced into routine clinical practice and there have been promising reports on the efficacy of biologic agents, particularly IL-6 antagonists such as tocilizumab, in treating these conditions. Along with these developments, which should improve outcomes in patients with GCA and PMR, new questions and unmet needs have emerged; future research should address which pathogenetic mechanisms contribute to the different phases and clinical phenotypes of GCA, what role imaging has in the early diagnosis and monitoring of GCA and PMR, and in which patients and phases of these diseases novel biologic drugs should be used. This article discusses the implications of recent developments in our understanding of GCA and PMR, as well as the unmet needs concerning epidemiology, pathogenesis, imaging and treatment of these diseases.