Serum IL-6 level trajectory for predicting the effectiveness and safety of tocilizumab in the treatment of refractory Takayasu arteritis

AIM

To explore the value of serial monitoring of serum interleukin-6 (IL-6) levels for predicting treatment response and occurrence of adverse events during tocilizumab (TCZ) treatment in refractory Takayasu arteritis (TAK).

METHODS

TAK patients receiving TCZ treatment were prospectively recruited and followed up at 1 month, 3 months and then every 3-6 months. Serum IL-6 levels were measured at each visit. Overall response was the combination of complete and partial response, requiring resolution of signs and symptoms, hsCRP and ESR level decreased at least by half, no progression on imaging and dose of glucocorticoid <15 mg/d.

RESULTS

Thirty-five patients with a median follow up duration of 17 [9-44] months were included. The change of IL-6 after TCZ treatment for 6 months compared to the baseline was significantly lower in patients achieved overall response at 6, 12, 18 and 24 months. The ratio of IL-6 at 6 months to baseline could predict overall response at 12 and 24 months after TCZ treatment. With a cutoff value of 1.6, the sensitivity and specificity were 83.3 % and 87.5 % for 12 months, while 100 % and 88.9 % for 24 months. Patients with the ratio less than 1.6 were also 9 times more likely to achieve sustained improvement without treatment intensification. No correlation between IL-6 dynamics and occurrence of adverse events was found.

CONCLUSIONS

The change of IL-6 levels after TCZ treatment for 6 months compared to the baseline can predict the overall treatment response at 12 months, 24 months and sustained improvement.

miR-146a and miR-146b regulate the expression of ICAM-1 in giant cell arteritis

Giant cell arteritis (GCA) is an inflammatory disease of large/medium-sized arteries. MiRNAs are small, non-coding RNAs that inhibit gene expression at post-transcriptional level. Several miRNAs have been shown to be dysregulated in temporal artery biopsies (TABs) from GCA patients, but their role is unknown. The aims of the present work were: to gain insight into the link between inflammation and miRNA up-regulation in GCA; to identify the role of miR-146a and miR-146b. Primary cultures from TABs were treated with IL-1β, IL-6, soluble IL-6R (sIL6R), IL-17, IL-22, IFNγ, LPS and PolyIC. Correlations between cytokine mRNA and miRNA levels were determined in inflamed TABs. Primary cultures from TABs, human aortic endothelial and smooth muscle cells and ex-vivo TAB sections were transfected with synthetic miR-146a and miR-146b to mimic miRNA activities. Cell viability, target gene expression, cytokine levels in culture supernatants were assayed. Treatment of primary cultures from TABs with IL-1β and IL-17 increased miR-146a expression while IL-1β, IL-6+sIL6R and IFNγ increased miR-146b expression. IFNγ and IL-1β mRNA levels correlated with miR-146a/b levels. Following transfection, cell viability decreased only in primary cultures from TABs. Moreover, transfection of miR-146a/b mimics increased ICAM-1 gene expression and production of the soluble form of ICAM-1 by primary cultures from TABs and by ex-vivo TABs. ICAM-1 expression was higher in inflamed than normal TABs and ICAM-1 levels correlated with miR-146a/b levels. Expression of miR-146a and miR-146b in GCA appeared to be driven by inflammatory cytokines (e.g. IL-1β, IFNγ). miR-146a and miR-146b seem responsible for the increase of soluble ICAM-1.

Ultrasonography in the assessment of disease activity in cranial and large-vessel giant cell arteritis: a prospective follow-up study

OBJECTIVES

We evaluated sensitivity to change and discriminative abilities of vascular US scores in disease monitoring in the follow-up of a prospective cohort of new-onset cranial and large-vessel (LV) GCA patients.

METHODS

Baseline and follow-up (8 weeks, 24 weeks and 15 months) US of temporal arteries (TA), carotid and axillary arteries (LV) included assessment of halo and measurement of the intima media complex (IMC). Max IMC, max halo IMC, sum IMC, sum halo IMC, mean IMC, halo count and the Southend halo score were calculated. The provisional OMERACT US score, OGUS, was obtained, taking the average of temporal arteries and axillary arteries IMCs divided by their normal cut-off values.

RESULTS

Baseline US was positive in 44/47 patients (72% TA, 72% LV). Sensitivity to change of all composite US scores containing TAs was evident by week 8 onward. LVs responded poorly and new axillary US lesions emerged in six patients despite clinical remission. The OGUS showed a large magnitude of change and is considered the score least prone to potential bias. All TA-based US scores showed moderate-strong correlation with disease activity markers. OGUS, TA halo count, Southend TA halo score, TA sum IMC and TA mean IMC showed potential to discriminate remission and relapse with area under the curve ≥0.8.

CONCLUSIONS

The OGUS is suggested as an outcome measurement for the assessment of treatment response in clinical trials. The abilities of US scores to discriminate remission and relapse are encouraging and should be further explored.

Biologic therapy in large and small vessels vasculitis, and Behçet's disease: Evidence- and practice-based guidance

OBJECTIVE

Vasculitis are a very heterogenous group of systemic autoimmune diseases, affecting large vessels (LVV), small vessels or presenting as a multisystemic variable vessel vasculitis. We aimed to define evidence and practice-based recommendations for the use of biologics in large and small vessels vasculitis, and Behçet's disease (BD).

METHODS

Recommendations were made by an independent expert panel, following a comprehensive literature review and two consensus rounds. The panel included 17 internal medicine experts with recognized practice on autoimmune diseases management. The literature review was systematic from 2014 until 2019 and later updated by cross-reference checking and experts' input until 2022. Preliminary recommendations were drafted by working groups for each disease and voted in two rounds, in June and September 2021. Recommendations with at least 75% agreement were approved.

RESULTS

A total of 32 final recommendations (10 for LVV treatment, 7 for small vessels vasculitis and 15 for BD) were approved by the experts and several biologic drugs were considered with different supporting evidence. Among LVV treatment options, tocilizumab presents the higher level of supporting evidence. Rituximab is recommended for treatment of severe/refractory cryoglobulinemic vasculitis. Infliximab and adalimumab are most recommended in treatment of severe/refractory BD manifestations. Other biologic drugs can be considered is specific presentations.

CONCLUSION

These evidence and practice-based recommendations are a contribute to treatment decision and may, ultimately, improve the outcome of patients living with these conditions.

Serum proteomics in giant cell arteritis in response to a three-day pulse of glucocorticoid followed by tocilizumab monotherapy (the GUSTO trial)

Objective

Proteome analyses in patients with newly diagnosed, untreated giant cell arteritis (GCA) have not been reported previously, nor are changes of protein expression upon treatment with glucocorticoids (GC) and/or tocilizumab (TCZ) known. The GUSTO trial allows to address these questions, provides the opportunity to learn about the differential effects of GC and TCZ on proteomics and may help to identify serum proteins to monitor disease activity.

Methods

Serum samples obtained from 16 patients with new-onset GCA at different time points (day 0, 3, 10, and week 4, 24, 52) during the GUSTO trial (NCT03745586) were examined for 1436 differentially expressed proteins (DEPs) based on proximity extension assay technology. The patients received 500 mg methylprednisolone intravenously for 3 consecutive days followed by TCZ monotherapy.

Results

When comparing day 0 (before the first GC infusion) with week 52 (lasting remission), 434 DEPs (213↑, 221↓) were identified. In response to treatment, the majority of changes occurred within 10 days. GC inversely regulated 25 proteins compared to remission. No difference was observed between weeks 24 and 52 during established remission and ongoing TCZ treatment. Expression of CCL7, MMP12, and CXCL9 was not regulated by IL6.

Conclusion

Disease-regulated serum proteins improved within 10 days and were normalized within 24 weeks, showing a kinetic corresponding to the gradual achievement of clinical remission. The proteins inversely regulated by GC and TCZ shed light on the differential effects of the two drugs. CCL7, CXCL9, and MMP12 are biomarkers that reflect disease activity despite normalized C-reactive protein levels.

Recent advances in the treatment of giant cell arteritis

Giant cell arteritis (GCA) is a systemic, granulomatous, large-vessel vasculitis that affects individuals over the age of 50 years. Morbidity from disease includes cranial manifestations which can cause irreversible blindness, while extra-cranial manifestations can cause vascular damage with large-artery stenosis, occlusions, aortitis, aneurysms, and dissections. Glucocorticoids while efficacious are associated with significant adverse effects. Furthermore, despite treatment with glucocorticoids, relapses are common. An understanding of the pathogenesis of GCA has led to the discovery of tocilizumab as an efficacious steroid-sparing therapy while additional therapeutic targets affecting different inflammatory pathways are under investigation. Surgical treatment may be indicated in cases of refractory ischemia or aortic complications but data on surgical outcomes are limited. Despite the recent advances, many unmet needs exist, including the identification of patients or subsets of GCA who would benefit from earlier initiation of adjunctive therapies, patients who may warrant long-term immunosuppression and medications that sustain permanent remission. The impact of medications like tocilizumab on long-term outcomes, including the development of aortic aneurysms and vascular damage also warrants investigation.

The role of autoimmunity and autoinflammation in giant cell arteritis: A systematic literature review

Giant cell arteritis is the most common form of large vessel vasculitis and preferentially involves large and medium-sized arteries in patients over the age of 50. Aggressive wall inflammation, neoangiogenesis and consecutive remodeling processes are the hallmark of the disease. Though etiology is unknown, cellular and humoral immunopathological processes are well understood. Matrix metalloproteinase-9 mediated tissue infiltration occurs through lysis of basal membranes in adventitial vessels. CD4+ cells attain residency in immunoprotected niches, differentiate into vasculitogenic effector cells and enforce further leukotaxis. Signaling pathways involve the NOTCH1-Jagged1 pathway opening vessel infiltration, CD28 mediated T-cell overstimulation, lost PD-1/PD-L1 co-inhibition and JAK/STAT signaling in interferon dependent responses. From a humoral perspective, IL-6 represents a classical cytokine and potential Th-cell differentiator whereas interferon-γ (IFN- γ) has been shown to induce chemokine ligands. Current therapies involve glucocorticoids, tocilizumab and methotrexate application. However, new agents, most notably JAK/STAT inhibitors, PD-1 agonists and MMP-9 blocking substances, are being evaluated in ongoing clinical trials.

Comparing treatment options for large vessel vasculitis

INTRODUCTION

Giant cell arteritis (GCA) and Takayasu arteritis (TAK) are the major forms of large vessel vasculitis (LVV).Glucocorticoids represent the cornerstone of LVV treatment, however, relapses and recurrences frequently occur when they are tapered or stopped, determining a prolonged exposure to glucocorticoids and a subsequent increased risk of glucocorticoid-related side effects. Therefore, conventional and biologic immunosuppressive drugs have been proposed to obtain a glucocorticoid-sparing effect.

AREAS COVERED

We searched PubMed® using the keywords "giant cell arteritis/drug therapy" and "Takayasu Arteritis/drug therapy" OR "Takayasu Arteritis/surgery". This review focuses on the management of LVV, based on the current evidence while highlighting the differences in terms of therapeutic management of TAK and GCA.

EXPERT OPINION

Conventional disease modifying anti-rheumatic drugs, such as methotrexate or azathioprine, are recommended in association to glucocorticoids for selected GCA and all TAK patients. Two randomized placebo-controlled trials recently demonstrated the efficacy of tocilizumab in reducing relapses and cumulative prednisone dosage in GCA patients with newly diagnosed or relapsing disease. Observational evidence and two small randomized controlled trials support the use of TNF-alpha inhibitors and tocilizumab as glucocorticoid-sparing agents in relapsing TAK, albeit high-quality evidence regarding the management of TAK is still lacking.

From Active to Non-active Giant Cell Arteritis: Longitudinal Monitoring of Patients on Glucocorticoid Therapy in Combination With Leflunomide

In the present study, we longitudinally monitored leukocyte subsets, expression of neutrophil surface adhesion molecules (CD62L and CD11b) and serum analytes in therapy-naïve patients with active giant cell arteritis (GCA). We collected blood samples at the baseline, and at weeks 1, 4, 12, 24, and 48 of follow-up, and evaluated short- and long-term effects of glucocorticoids (GC) vs. GC and leflunomide. Our aim was to identify candidate biomarkers that could be used to monitor disease activity and predict an increased risk of a relapse. Following high doses of GC, the numbers of CD4+ T-lymphocytes and B-lymphocytes transiently increased and then subsided when GC dose tapering started at week 4. In contrast, the numbers of neutrophils significantly increased during the follow-up time of 12 weeks compared to pre-treatment time. Neutrophil CD62L rapidly diminished after initiation of GC therapy, however its expression remained low at week 48, only in patients under combinatorial therapy with leflunomide. Levels of acute phase reactant SAA and IL-6 decreased significantly after treatment with GC and leflunomide, while levels of IL-8, IL-18, and CHI3L1 did not change significantly during the follow-up period. CHI3L1 was associated with signs of transmural inflammation and vessel occlusion and might therefore serve as a marker of fully developed active GCA, and a promising therapeutic target. Patients with relapses had higher levels of IL-23 at presentation than patients without relapses (p = 0.021). Additionally, the levels of IL-23 were higher at the time of relapse compared to the last follow-up point before relapse. IL-23 might present a promising biomarker of uncontrolled and active disease and could give early indication of upcoming relapses.

Progression of Large Vessel Disease in Patients With Giant Cell Arteritis-Associated Ischemic Stroke: The Role of Vascular Imaging: A Case Series

OBJECTIVE

Giant cell arteritis (GCA) can cause ischemic stroke (IS) due to the involvement of the internal carotid and vertebral arteries. The aim of our study is to describe the pattern of stroke recurrence in patients with GCA-related IS and the role of vascular imaging in the follow-up of these patients.

METHODS

We conducted an observational study of 2417 consecutive patients diagnosed with IS and admitted to our hospital from January 2012 to December 2018. We reviewed patients with GCA-related IS and the relationship of erythrocyte sedimentation rate, C-reactive protein, vascular status, and clinical course.

RESULTS

We found 4 patients with GCA-related IS among 2417 IS patients: 1 woman (25%); median age, 77.3 years (67-85 years). Mean follow-up was 3.6 years. Initial vascular workup showed vertebral artery stenosis in all of them and internal carotid artery stenosis in 2 patients. All patients were started on treatment with full-dose prednisone, associated with methotrexate in 2 cases. Follow-up color-coded duplex sonography disclosed progression of arterial stenoses in 3 patients who suffered a recurrent IS (days after index stroke; mean, 27.67 [SD, 10.97]) despite normal C-reactive protein and erythrocyte sedimentation rate values.

CONCLUSIONS

Vascular imaging, especially with color-coded duplex sonography, could play a role in the follow-up of patients with GCA-related IS and identify those patients with higher risk of recurrent stroke.

Functionally Heterogenous Macrophage Subsets in the Pathogenesis of Giant Cell Arteritis: Novel Targets for Disease Monitoring and Treatment

Giant cell arteritis (GCA) is a granulomatous large-vessel vasculitis that affects adults above 50 years of age. In GCA, circulating monocytes are recruited to the inflamed arteries. With cues from the vascular microenvironment, they differentiate into macrophages and play important roles in the pathogenesis of GCA via pro-inflammatory cytokine production and vascular remodeling. However, a deeper understanding of macrophage heterogeneity in GCA pathogenesis is needed to assist the development of novel diagnostic tools and targeted therapies. Here, we review the current knowledge on macrophage heterogeneity and diverse functions of macrophage subsets in the pathogenesis of GCA. We next discuss the possibility to exploit their heterogeneity as a source of novel biomarkers and as targets for nuclear imaging. Finally, we discuss novel macrophage-targeted therapies and future directions for targeting these cells in GCA.

Diagnostic utility of serum biomarkers in large vessel vasculitis and their correlation with positron emission tomography

OBJECTIVES

To investigate the association between vascular inflammation, as detected by positron emission tomography (PET) imaging and interleukin-6 (IL-6), pentraxin3, and B-cell-activating factor (BAFF) in subjects with LVV.

METHODS

The study included newly diagnosed giant cell arteritis (GCA, n = 27) or Takayasu arteritis (n = 9) patients and healthy control (HC, n = 31) subjects. PET scan and blood samples were obtained before the introduction of treatments. IL-6, PTX3, and BAFF levels were determined quantitatively by enzyme-linked immunosorbent assay kits.

RESULTS

Thirty-six patients with LVV (20 females, 16 males; age 64.5 ± 16.6 years) and 31 HC (14 females, 17 males; age 37.1 ± 9.6 years) were included. Serum levels of IL-6, PTX3, and BAFF were increased in patients with newly diagnosed LVV compared with healthy control subjects. In receiver operating characteristics (ROC) analysis, serum IL-6 and BAFF provided excellent discrimination of newly diagnosed LVV patients from HC (area under the ROC curve of >0.90 and >0.80, respectively). None of the inflammatory markers correlated with vascular inflammatory activity determined by PET scanning.

CONCLUSIONS

Our results suggest that IL-6 and BAFF may serve as markers of large vessel vasculitis, while PTX3 is not useful. None of the inflammatory markers correlated with PET assessed vasculitis activity.

A Distinct Macrophage Subset Mediating Tissue Destruction and Neovascularization in Giant Cell Arteritis: Implication of the YKL-40 - IL-13 Receptor α2 Axis

Objective

Macrophages mediate inflammation, angiogenesis, and tissue destruction in giant cell arteritis (GCA). Serum levels of the macrophage‐associated protein YKL‐40 (chitinase 3–like protein 1), previously linked to angiogenesis and tissue remodeling, remain elevated in GCA despite glucocorticoid treatment. This study was undertaken to investigate the contribution of YKL‐40 to vasculopathy in GCA.

Methods

Immunohistochemistry was performed on GCA temporal artery biopsy specimens (n = 12) and aortas (n = 10) for detection of YKL‐40, its receptor interleukin‐13 receptor α2 (IL‐13Rα2), macrophage markers PU.1 and CD206, and the tissue‐destructive protein matrix metalloproteinase 9 (MMP‐9). Ten noninflamed temporal artery biopsy specimens served as controls. In vitro experiments with granulocyte–macrophage colony‐stimulating factor (GM‐CSF)– or macrophage colony‐stimulating factor (M‐CSF)–skewed monocyte‐derived macrophages were conducted to study the dynamics of YKL‐40 production. Next, small interfering RNA–mediated knockdown of YKL‐40 in GM‐CSF–skewed macrophages was performed to study its effect on MMP‐9 production. Finally, the angiogenic potential of YKL‐40 was investigated by tube formation experiments using human microvascular endothelial cells (HMVECs).

Results

YKL‐40 was abundantly expressed by a CD206+MMP‐9+ macrophage subset in inflamed temporal arteries and aortas. GM‐CSF–skewed macrophages from GCA patients, but not healthy controls, released significantly higher levels of YKL‐40 compared to M‐CSF–skewed macrophages (P = 0.039). In inflamed temporal arteries, IL‐13Rα2 was expressed by macrophages and endothelial cells. Functionally, knockdown of YKL‐40 led to a 10–50% reduction in MMP‐9 production by macrophages, whereas exposure of HMVECS to YKL‐40 led to significantly increased tube formation.

Conclusion

In GCA, a GM‐CSF–skewed, CD206+MMP‐9+ macrophage subset expresses high levels of YKL‐40 which may stimulate tissue destruction and angiogenesis through IL‐13Rα2 signaling. Targeting YKL‐40 or GM‐CSF may inhibit macrophages that are currently insufficiently suppressed by glucocorticoids.

[Glucocorticoids in the treatment of giant cell arteritis : How much, how long and how to spare?]

Treatment of giant cell arteritis (GCA) with high-dose glucocorticoids (GC) regularly leads to a control of the inflammatory activity, so that high-dose GC is still the recommended standard treatment in the current guidelines; however, after discontinuation of GC treatment or reduction of the GC dosage, relapses occur in up to 70% of patients in the further course of the disease, making it necessary to resume treatment or increase the dosage. As a consequence many patients therefore have to be treated with GC often in high doses over several years, which results in a high cumulative exposure to GC. The risk for GC-associated diseases, such as diabetes, glaucoma, osteoporosis or severe infections is therefore significantly increased for patients with giant cell arteritis. For patients with GC-associated comorbidities or increased risk of developing them or patients with a relapse, the current guidelines therefore recommend GC-sparing treatment with tocilizumab or alternatively methotrexate. It is currently unclear over what period of time patients should be treated with GC and GC-sparing treatment, since high-quality study data on de-escalation strategies for GCA are currently still lacking. Decisions on treatment duration and intensity must therefore be made individually for each patient, taking into account general and patient-specific risk factors for a GC-dependent course, GCA-associated vascular damage (stenoses, aneurysms, visual loss) and treatment-associated complications.

Giant Cell Arteritis and Cardiac Comorbidity

Giant cell arteritis (GCA) is a large vessel vasculitis with a pathogenesis that involves two CD4 T-helper cell lineages, Th1 and Th17. The goal of GCA treatment is to achieve clinical remission and prevent complications, especially vision loss. Despite recent advances in treatment and diagnostic modalities for GCA, there continues to be a gap in the medical literature in addressing treatment and follow-up for patients with GCA after clinical remission is achieved. Of the most important issues to address in this patient population by rheumatologists and primary care physicians alike, is that of cardiovascular disease (CVD) risks in GCA patients associated with the vasculitis and its mainstay of treatment with high-dose glucocorticoids over a prolonged period of time. Physicians must be aware of the CVD events that have been observed in a higher proportion compared to the general population in GCA patients, including strokes, thoracic aortic aneurysms and dissections, myocardial infarctions, and peripheral vascular disease. This review will focus on the risk of CVD in GCA patients, with recommendations for management and follow-up.

Blood Biomarkers for Monitoring and Prognosis of Large Vessel Vasculitides

PURPOSE OF REVIEW

Large vessel vasculitides (LVVs) are inflammatory conditions of the wall of large-sized arteries, mainly represented by giant cell arteritis (GCA) and Takayasu arteritis (TA). The inflammatory process within the vessel wall can lead to serious consequences such as development of aneurysms, strokes and blindness; therefore, early diagnosis and follow-up of LVV are fundamental. However, the arterial wall is poorly accessible and blood biomarkers are intended to help physicians not only in disease diagnosis but also in monitoring and defining the prognosis of these conditions, thus assisting therapeutic decisions and favouring personalised management. The field is the object of intense research as the identification of reliable biomarkers is likely to shed light on the mechanisms of disease progression and arterial remodelling. In this review, we will discuss the role of blood biomarkers in LVVs in the light of the latest evidence.

RECENT FINDINGS

In clinical practice, the most widely performed laboratory investigations are the erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP). However, these indices may be within normal limits during disease relapse and they are not reliable in patients receiving interleukin-6 (IL-6) receptor inhibitors. New biomarkers struggle to gain traction in clinical practice and no molecule with good accuracy has been identified to date. IL-6, a pro-inflammatory cytokine that drives CRP synthesis and increases the ESR, is one of the most promising biomarkers in the field. IL-6 analysis is increasingly performed, and serum levels are more sensitive than ESR for active GCA and might reflect persistent inflammation with high risk of relapse in patients on IL-6 receptor inhibitors. A future with biomarkers that reflect different disease features is an important aspiration. Accordingly, intense effort is being made to identify IL-6-independent inflammatory biomarkers, such as S100 proteins, pentraxin-3 and osteopontin. Moreover, metalloproteinases such as MMP2/9 and angiogenic modulators such as VEGF, YLK-40 and angiopoietins are being studied as markers of arterial remodelling. Lastly, biomarkers indicating organ damage may guide prognostic stratification as well as emergency therapeutic decisions: the most promising biomarkers so far identified are NT-proBNP, which reflects myocardial strain; pentraxin-3, which has been associated with recent optic nerve ischemia; and endothelin-1, which is associated with ischaemic complications. Currently, the use of these molecules in clinical practice is limited because of their restricted availability, lack of sufficient studies supporting their validity and associated costs. Further evidence is required to better interpret their biological and clinical value.

Recent advances in the diagnosis and management of giant cell arteritis

PURPOSE OF REVIEW

Giant cell arteritis (GCA) has classically been diagnosed by temporal artery biopsy and treated with high-dose, long-term glucocorticoid therapy. Noninvasive imaging increasingly is employed for diagnostic purposes, but further studies are needed to determine the role of imaging in monitoring longitudinal disease activity. Glucocorticoid-sparing therapy mitigates the numerous adverse effects of glucocorticoids. This review addresses new developments in these areas.

RECENT FINDINGS

For diagnosis, when performed at a center with expertise in its use, temporal artery ultrasound has an estimated sensitivity and specificity of 78 and 79%, respectively. State-of-the-art time-of-flight positron emission tomography/computed tomography (PET/CT) has an estimated sensitivity and specificity of 71 and 91%, respectively. The sensitivities of both imaging modalities decrease following glucocorticoid administration. Tocilizumab is an effective glucocorticoid-sparing therapy, demonstrating sustained glucocorticoid-free remission in 56% of patients receiving weekly tocilizumab compared with 18% of patients receiving a 52-week prednisone taper. The traditional acute phase reactants are of no value in patients treated with interleukin-6 receptor (IL6-R) blockade, and thus, the development of new biomarkers is an important priority in the field.

SUMMARY

Noninvasive imaging techniques are increasingly used in the absence of temporal artery biopsy to confirm diagnostic suspicions of GCA. Tocilizumab reduces the cumulative glucocorticoid exposure and increases the rate of sustained remission. Ongoing efforts are directed towards new methods to identify disease flares.

Treatment of Giant Cell Arteritis and Takayasu Arteritis-Current and Future

Purpose of Review

Guidelines for the management of large vessel vasculitides have been recently updated by several scientific societies. We have evaluated the current recommendations for treatment of giant cell arteritis (GCA) and Takayasu arteritis (TA) and addressed potential future therapeutic strategies.

Recent Findings

While glucocorticoids (GCs) remain the gold standard for induction of remission, many patients relapse and acquire high cumulative GC exposure. Thus, GC-sparing therapies such as methotrexate are recommended for selected patients with GCA and all patients with TA. Recent high-quality evidence shows that tocilizumab is an effective GC-sparing agent in GCA. Non-biologic and biologic immunomodulators also appear to have GC-sparing properties in TA.

Summary

Tocilizumab is now considered to be part of the standard treatment for GCA, particularly with relapsing disease, but questions on its use such as length of treatment and monitoring of disease activity remain open. High-quality evidence to guide treatment of TA is still lacking.

The Role of Multimodality Imaging in Monitoring Disease Activity and Therapeutic Response to Tocilizumab in Giant Cell Arteritis

Introduction

Giant cell arteritis (GCA) is a large vessel (LV) vasculitis, mainly affecting elder patients. Monitoring GCA activity during tocilizumab (TCZ) treatment is an unmet need, since low serum levels of C-reactive protein (CRP) during treatment may underestimate disease activity. To date, few data are available on the role of different imaging techniques in monitoring GCA activity and response to treatment. We report herein a cohort of GCA patients treated with TCZ and followed up with multimodal imaging. Patients and Methods. We collected clinical, laboratory, and imaging data of 11 GCA patients treated with TCZ 162 mg subcutaneously every week. Disease activity was assessed at baseline and within 12 months from the start of treatment using different imaging techniques such as color Doppler ultrasonography (CDUS), magnetic resonance imaging/angiography (MRI/MRA), computed tomography angiography (CTA), and/or positron emission tomography (PET).

Results

Four patients were affected by cranial and 7 by LV-GCA. All patients were treated with oral glucocorticoids (GCs) (mean dose 55.68 mg ± 8.19 of prednisone or equivalent) in combination with TCZ. Treatment was preceded in 5 cases by 3 intravenous boluses of 1000 mg methylprednisolone. A significant decrease of the mean dose of oral GCs was observed between baseline and the last follow-up visit (4.65 ± 3.69 mg) (p = 0.003). TCZ treatment significantly decreased erythrocyte sedimentation rate (p < 0.01) and CRP levels (p < 0.01). At follow-up (mean 8.18 ± 3.63 months), all patients were in clinical and serological remission. Moreover, PET, CDUS, MRI/MRA, and CTA did not show any LVV finding.

Conclusions

Our study highlights TCZ efficacy in inducing GCA remission and its steroid-sparing effect. We highlighted a reliability of imaging procedures in the evaluation of disease activity and treatment response. A close disease monitoring with imaging techniques should be taken into account in GCA patients during TCZ treatment.

[Polymyalgia rheumatica and Giant Cell Arteritis - Update on Diagnosis and Therapy]

Polymyalgia rheumatica and Giant Cell Arteritis - Update on Diagnosis and Therapy Abstract. Polymyalgia rheumatica (PMR) is an inflammatory syndrome which often co-incides with giant cell arteritis (GCA). Due to unspecific symptoms and a plethora of possible alternative diagnoses, PMR often represents a diagnostic challenge. The use of ultrasound, but also other imaging methods has improved and accelerated the time to diagnosis in PMR and GCA, so that complications such as blindness can be reduced. Glucocorticoids are still the main initial therapy for both diseases. Although further research is needed concerning prevention of and screening for long term complications for GCA, the efficacy of biologicals, namely tocilizumab, has markedly increased therapeutic options for GCA and allows for a reduction of side effects.

Mechanism and biomarkers in aortitis--a review

Aortitis can be the manifestation of an underlying infectious or noninfectious disease process. An autoimmune cause is suggested in a large proportion of noninfectious causes. Similar to other autoimmune diseases, the pathophysiology of aortitis has been investigated in detail, but the etiology remains unknown. Most cases of aortitis often go undetected for a long time and are often identified at late stages of the disease. Recent advances in imaging techniques have significantly improved the diagnosis of aortitis. However, significant challenges associated with the imaging techniques limit their use. Several routine inflammation-based markers, such as erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and inflammatory cytokines, are nonspecific and, therefore, have limited use in the diagnosis of aortitis. The search for more specific serum biomarkers, which can facilitate detection and progression is under progress. Several autoantibodies have been identified, but assigning their role in the pathogenesis as well as their specificity remains a challenge. The current review addresses some of these issues in detail. KEY MESSAGES: • Noninfectious aortitis is an autoimmune disease. • Several biomarkers, including cytokines and autoantibodies, are increased in aortitis. • Imaging techniques, commonly used to detect aortitis, are associated with the high cost and technical challenges. • There is a need to develop low-cost biomarker-based detection tools. • The knowledge of biomarkers in aortitis detection is discussed.

Treat to Target: A Valid Concept for Management of Polymyalgia Rheumatica and Giant Cell Arteritis?

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are common inflammatory diseases of the elderly. They have variable clinical courses and are usually treated with glucocorticoids (GCs). Relapses are frequent in both conditions. Physicians should balance the tradeoff of treatment-related adverse events and risk of relapse. The ultimate goal of treatment is control of the disease while maintaining patient well-being. A treat-to-target approach may achieve the aim of controlling inflammation and preserving patient's functioning and quality of life, and would require pursuit and evaluation of clinical, laboratory, imaging, and structural targets to tackle the different manifestations of GCA and PMR.

Leukocyte Dynamics Reveal a Persistent Myeloid Dominance in Giant Cell Arteritis and Polymyalgia Rheumatica

Giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) are inflammatory diseases requiring long-term glucocorticoid treatment. Limited data on dynamics in leukocyte counts before, during and after treatment are available. Leukocyte counts were measured, as cellular markers of inflammation, at fixed time points in our prospectively studied cohort of pre-treatment glucocorticoid-naive GCA (N = 42) and PMR (N = 31) patients. Values were compared with age-matched healthy controls (HCs; N = 51) and infection controls (N = 16). We report that before start of treatment monocyte and neutrophil counts were higher in GCA and PMR patients than in HCs, while NK- and B-cell counts were lower. C-reactive protein (CRP) levels correlated positively with monocyte counts in GCA, and negatively with B-cell and NK-cell counts in PMR. During glucocorticoid treatment, myeloid subsets remained elevated whereas lymphoid subsets tended to fluctuate. Interestingly, erythrocyte sedimentation rate (ESR) outperformed CRP as marker for relapses in GCA. We defined stable treatment-free remission groups in both GCA and PMR. GCA patients in treatment-free remission still demonstrated elevated monocytes, neutrophils, ESR, and platelets. PMR patients in treatment-free remission had normalized levels of inflammation markers, but did have elevated monocytes, lowered CD8+ T-cell counts and lowered NK-cell counts. Finally, we showed that low hemoglobin level was predictive for long-term GC treatment in PMR. Overall, leukocyte composition shifts toward the myeloid lineage in GCA and PMR. This myeloid profile, likely induced by effects of inflammation on hematopoietic stem cell differentiation, persisted during glucocorticoid treatment. Surprisingly, the myeloid profile was retained in treatment-free remission, which may reflect ongoing subclinical inflammation.

New-onset cutaneous sarcoidosis under tocilizumab treatment for giant cell arteritis: a quasi-paradoxical adverse drug reaction. Case report and literature review

Background

New-onset sarcoidosis has been previously described in three case reports in patients affected by rheumatoid arthritis treated with tocilizumab (TCZ). The existence of a cause-effect mechanism between the biological treatment and the onset of the illness is still being debated.

Patient concerns

A 74-year-old woman was diagnosed with giant cell arteritis (GCA). The first-line treatment with glucocorticoids; and the second-line with methotrexate and low-dose glucocorticoids were stopped due to multiple pathological vertebral fractures and insufficient biological and clinical response. The cytotoxic agent, cyclophosphamide, was then introduced and in turn stopped, because of gastrointestinal side effects. Thereafter a treatment with TCZ was begun. The patient experienced good clinical response; however, 8 months later she developed painful hyper-pigmented reddish cutaneous micronodular lesions localized to the abdomen and thorax. A cutaneous biopsy was performed, and histological analysis showed noncaseating epithelioid granulomas in the hypodermis. The diagnosis of cutaneous sarcoidosis was made.

Interventions

Topical corticosteroids were administered and, as requested by the patient, TCZ was discontinued with slow but complete resolution of the skin lesions. After TCZ discontinuation however, the GCA flared and the patient's symptoms and biological abnormalities reappeared. Thus, after a 6-month suspension, TCZ was re-administered. At 2 months later the skin lesions compatible with cutaneous sarcoidosis reappeared. Topical corticosteroids were once again prescribed and as suggested by the patient the TCZ posology was reduced. The patient's symptoms disappeared, and the cutaneous lesions resolved.

Lessons

The time elapsed from TCZ treatment start and the onset of cutaneous sarcoidosis, as well as its recurrence after TCZ suspension and rechallenge supported the diagnosis of a drug-induced reaction. To the best of our knowledge, this case report represents the first instance of cutaneous sarcoidosis most likely induced by TCZ in patients affected by GCA. In addition, our case emphasizes that although TCZ in monotherapy confirms to be an effective treatment for GCA, further immunological disorders could be unmasked, and the discussed side effect of the drug could be dose-dependent.

Risk of relapse after discontinuation of tocilizumab therapy in giant cell arteritis

Objective

It is currently unknown how long GCA should be treated with tocilizumab. In the first randomized controlled trial, the biologic agent was stopped after 52 weeks. We therefore studied what proportion of patients relapsed, when relapses occurred and whether factors might predict relapse after tocilizumab treatment discontinuation.

Methods

All patients in the tocilizumab arm who had received a 52-week treatment were evaluated. In case of lasting remission, magnetic resonance angiography (MRA) was performed and sera were taken to search for biomarkers associated with subclinical disease activity.

Results

Seventeen of 20 patients randomized to the tocilizumab treatment arm were in lasting remission without any co-medication at week 52. Mean follow-up after study end was 28.1 months (range 17–44). Eight patients relapsed after a mean of 6.3 months (range 2–14) (six within the first 5 months, two patients at months 13 and 14, respectively). Relapsing patients were younger and showed more signs of mural enhancement in MRA compared with non-relapsing patients. MRA documented low-intensity vessel wall signals in all subjects. No morphological changes such as formation of aneurysm of aorta occurred. Biomarkers in sera did not indicate subclinical disease activity: levels of IL-6, MMP-3, soluble TNF receptor 2, soluble CD163, soluble intercellular adhesion molecule-1 and Pentraxin-3 did not differ from matched healthy controls.

Conclusion

The data show that a 52-week treatment with tocilizumab induces a lasting remission that persists in half of the patients after treatment stop. None of the clinical, serological or MRA findings qualify to predict relapse. Remarkably, MRA revealed a persisting wall enhancement of the descending aorta.

Markers of angiogenesis and macrophage products for predicting disease course and monitoring vascular inflammation in giant cell arteritis

OBJECTIVE

GCA, a systemic vasculitis, is characterized by an IL-6-dependent acute-phase response. This response is typically suppressed by treatment rendering CRP/ESR unreliable for monitoring vascular inflammation. Also, there are no accurate biomarkers predicting a non-favourable disease course. Here we investigated macrophage products and markers of angiogenesis as biomarkers for prognosis and monitoring of vascular inflammation.

METHODS

Forty-one newly diagnosed, glucocorticoid-naive GCA patients were prospectively followed for relapses and glucocorticoid requirement for a median of 30 months (range 0-71). Serum markers at baseline and during follow-up were compared with 33 age-matched healthy controls and 13 infection controls. Concentrations of IL-6, serum amyloid A, soluble CD163, calprotectin, YKL-40, VEGF, angiopoietin-1 and -2 and sTie2 were determined by ELISA/Luminex assay.

RESULTS

Serum concentrations of all markers, but not angiopoietin-1, were elevated in GCA patients at baseline when compared with healthy controls. High VEGF (P = 0.0025) and angiopoietin-1 (P = 0.0174) and low YKL-40 (P = 0.0369) levels at baseline were predictive of a short time to glucocorticoid-free remission. Elevated angiopoietin-2 levels were associated with an imminent relapse during treatment (P < 0.05). IL-6 correlated strongly with acute-phase markers and soluble CD163 but not with markers of angiogenesis, YKL-40 or calprotectin. Glucocorticoid treatment down-modulated all markers except for calprotectin and YKL-40. Tissue expression of markers in temporal arteries was confirmed.

CONCLUSION

Markers of angiogenesis at baseline and during treatment predict GCA disease course, suggesting utility in patient stratification for glucocorticoid-sparing therapy. Calprotectin and YKL-40 are candidate markers for monitoring vessel wall inflammation.

Utility of serological biomarkers for giant cell arteritis in a large cohort of treatment-naïve patients

Early diagnosis and treatment of giant cell arteritis (GCA) is crucial for preventing ischemic complications. Multiple serological markers have been identified; however, there is a distinct lack of predicting markers for GCA relapse and complications. Our main objective was to identify serological parameters in a large cohort of treatment-naïve GCA patients, which could support clinicians in evaluating the course of the disease. Clinical data was gathered, along with analyte detection using Luminex technology, ELISA, and nephelometry, among others. Unsupervised hierarchical clustering and principal component analysis of analyte profiles were performed to determine delineation of GCA patients and healthy blood donors (HBDs). Highest, significantly elevated analytes in GCA patients were SAA (83-fold > HBDs median values), IL-23 (58-fold), and IL-6 (11-fold). Importantly, we show for the first time significantly changed levels of MARCO, alpha-fetoprotein, protein C, resistin, TNC, TNF RI, M-CSF, IL-18, and IL-31 in GCA versus HBDs. Changes in levels of SAA, CRP, haptoglobin, ESR, MMP-1 and MMP-2, and TNF-alpha were found associated with relapse and visual disturbances. aCL IgG was associated with limb artery involvement, even following adjustment for multiple testing. Principal component analysis revealed clear delineation between HBDs and GCA patients. Our study reveals biomarker clusters in a large cohort of patients with GCA and emphasizes the importance of using groups of serological biomarkers, such as acute phase proteins, MMPs, and cytokines (e.g. TNF-alpha) that could provide crucial insight into GCA complications and progression, leading to a more personalized disease management.