A phase 3 randomized, double-blind, placebo-controlled study to evaluate the efficacy and safety of sarilumab in patients with giant cell arteritis

The Impact of IL-17A Inhibition in Rheumatic and Musculoskeletal Diseases: Current Insights and Future Prospects

Interleukin-17A (IL-17A) plays a pivotal role in many rheumatic immune-mediated inflammatory diseases. Targeting the IL-17 pathway has transformed the way psoriatic arthritis (PsA) and axial spondyloarthritis (axSpA) are managed, with a number of IL-17A inhibitors now available for treating rheumatic and musculoskeletal diseases. This narrative review will describe the opportunities presented by novel imaging techniques in understanding the metabolic and mechanical changes that characterize the pathogenesis of PsA and axSpA. It will look at the current consensus definitions of early disease in PsA and axSpA, present evidence for the benefit of early treatment, and highlight the gaps in current knowledge. Finally, it will describe novel treatment targets to address the unmet needs in giant cell arteritis (GCA) and polymyalgia rheumatica (PMR) and discuss the potential role of IL-17A inhibition in treating GCA and PMR.

Takayasu arteritis: a geographically distant but immunologically proximal MHC-I-opathy

Takayasu arteritis, a granulomatosis vasculitis with a pathogenesis that is poorly defined but known to be associated with HLA-B*52, shares many features with other MHC-I-opathies. In addition to the shared clinical features of inflammatory bowel diseases, cutaneous inflammation, and HLA-B*52, is shared association of an IL12B single- nucleotide polymorphism encoding the common IL-12 and IL-23 p40 subunit, which might affect not only type 17 cytokine responses, but also IFNγ and TNF production-the cardinal type 1 cytokines in granuloma formation. Considering the translational context of responses to TNF inhibition in Takayasu arteritis, in this Personal View we propose Takayasu arteritis as a type 1 MHC-I-opathy. Additionally, type 1 and type 17 T-cell immune responses show immune plasticity, which connects the overlapping features of Takayasu arteritis and spondyloarthritis spectrum disorders, providing a basis for shared anti-TNF responses, and points to p40 and IFNγ cytokine antagonism and potential selective CD8 T-cell repertoire ablation.

Population Pharmacokinetics and Exposure-Response Analyses of Sarilumab in Patients with Polymyalgia Rheumatica

Sarilumab (interleukin-6 receptor inhibitor) is approved in the United States and Europe for polymyalgia rheumatica (PMR). This study characterized sarilumab pharmacokinetics (PK) and assessed the influence of intrinsic and extrinsic factors on PK in patients with PMR and giant cell arteritis (GCA). Exposure-responses analyses were conducted to evaluate the PK-pharmacodynamic (PD) relationships of sarilumab with key efficacy and safety endpoints in patients with PMR (NCT03600818). Population (Pop) PK analysis was conducted using pooled PK data from two phase III studies including 58 patients with PMR and 40 with GCA (NCT03600805). This Pop PK model was developed by re-estimating parameters from a previous rheumatoid arthritis (RA) model. The main source of intrinsic PK variability in patients with PMR was body weight, with decreasing weight causing increased sarilumab exposure. The population mean apparent clearance for patients with PMR was lower than for patients with RA due to higher albumin, lower creatinine clearance, and lower C-reactive protein (CRP) in PMR than in RA. Individual exposures at steady state overlapped among patients with PMR, GCA, and RA. PK-PD relationships showed that greater sarilumab Ctrough in patients with PMR were associated with increasing total sIL-6Rα and decreasing CRP. There was a slight increase in patients achieving sustained remission at Week 52 and a decrease in absolute neutrophil count with increasing sarilumab Ctrough plateauing at 20-25 mg/L. The PD effect of sarilumab plateaued at Ctrough of 20-25 mg/L for target saturation, efficacy, and safety endpoints, supporting a dosage of 200 mg every 2 weeks for PMR.

Tocilizumab (TCZ) for Giant Cell Arteritis: Clinical Outcomes Following Relapses and TCZ Discontinuation Due to Adverse Events

OBJECTIVE

Tocilizumab (TCZ) is effective for giant cell arteritis (GCA). However, little is known regarding treatment modification and clinical outcomes after unfavorable events such as GCA relapses or TCZ discontinuation due to adverse events (AEs).

METHODS

This multicenter retrospective study included patients with GCA who initiated TCZ from 2008 to 2021 at 5 Japanese hospitals. GCA relapses and TCZ-related AEs were monitored for 2 years after TCZ initiation. In patients with GCA relapses, subsequent clinical courses, including relapse symptoms and treatment modification, were followed for 90 days after the relapses. Similarly, patients who discontinued TCZ because of AEs were additionally followed until 1 year after the TCZ discontinuation to evaluate AEs, relapses, and treatment changes.

RESULTS

Of 62 eligible patients, 10 patients (16%) relapsed after initiating TCZ therapy. Most relapses (8 of 10) occurred after extending TCZ intervals or discontinuing TCZ. Combinations of adjusting TCZ intervals, adjusting glucocorticoid (GC) dose, and/or adding or increasing methotrexate (MTX) therapy could manage the relapses without serious complications. In the entire cohort, AEs occurred in 28 patients (45%), and 8 patients (13%) discontinued TCZ because of AEs. After AE-related TCZ discontinuation, 6 patients attempted to taper GCs without other immunosuppressive therapy (IST), and 4 subsequently relapsed. In contrast, 2 patients who used other IST or biologic therapy could decrease GCs without relapses.

CONCLUSION

Although GCA relapses can occur after initiating TCZ therapy, most relapses can be safely managed by adjusting TCZ, GC, and/or MTX doses. Adding IST or biologic treatments may potentially be related to preventing relapses when patients discontinue TCZ because of AEs.

Targeting interleukin-6 pathways in giant cell arteritis management: A narrative review of evidence

Giant cell arteritis (GCA) is a chronic inflammatory vasculitis with a significant impact on vascular and patient health. It may present with non-specific symptoms and can lead to severe complications if not managed effectively. This narrative review explores the treatment of GCA with interleukin-6 (IL-6) pathway inhibitors, focusing on key studies from selected databases published between 2018 and 2024. The findings reveal that the current treatment primarily involves glucocorticoids (GCs), but their long-term use is associated with adverse effects. Targeting the IL-6 pathway offers therapeutic benefits by reducing inflammation and sparing GC use. Tocilizumab, a humanized immunoglobulin G1κ monoclonal antibody that blocks the IL-6 receptor, has demonstrated efficacy in achieving sustained remission and improving quality of life in people with GCA. However, challenges remain in understanding the optimal duration of therapy, managing relapse upon discontinuation, and addressing long-term structural vascular outcomes. Additional research is needed to further elucidate the complex pathogenesis of GCA and to optimize treatment strategies to achieve sustained remission both clinically and histologically while minimizing adverse effects. This review provides a comprehensive overview of the evidence of IL-6 inhibition in GCA management, highlighting both its therapeutic benefits and the challenges associated with its use.

Polymyalgia rheumatica and giant cell arteritis: diagnosis and management

PURPOSE OF REVIEW

There have been advances in the diagnosis and treatment of giant cell arteritis (GCA) and polymyalgia rheumatica (PMR).

RECENT FINDINGS

Themes in PMR and GCA include classification criteria, ultrasound imaging of temporal and axillary arteries replacing biopsies for diagnosis of GCA, faster diagnosis and treatment with rapid access clinics for suspected GCA, and expanding treatment options with the goal of rapid suppression of inflammation and sparing steroids.

SUMMARY

Treatment is aimed at suppressing inflammation quickly in both GCA and PMR. Randomized trials have demonstrated success in reducing glucocorticoids when adding advanced therapies such as interleukin 6 (IL6) inhibitors. Other treatments including Janus kinase (JAK) inhibitors (especially a phase 3 trial of upadacitinib at 15 mg daily and secukinumab (an IL17 inhibitor) are being tested. Some uncontrolled GCA protocols are limiting glucocorticoids to initial IV pulse therapy only or rapid tapering of oral glucocorticoids with upfront treatment with tocilizumab. There is uncertainty of who should have an advanced therapy and how long to use it for and what order to consider advanced therapies when treatment fails. In PMR, studies are performed when patients cannot taper glucocorticoids effectively, whereas in GCA, advanced therapies are started with disease onset or with recurrent GCA.

[News on the treatment of large vessel vasculitis]

Large vessel vasculitis, such as giant cell arteritis (GCA) and Takayasu arteritis (TAK) are primarily manifested on large and medium-sized arteries. While GCA mainly affects older people after the 6th decade of life onwards, TAK mainly affects young women under the age of 40 years. Glucocorticoids (GC) are still the standard treatment for both diseases. Refractory courses and relapses in particular often lead to long-term treatment with high cumulative doses of GC, which can lead to increased morbidity and mortality. To date, only the interleukin 6 (IL-6) receptor blocker tocilizumab has been approved for the treatment of GCA. The data on methotrexate and other conventional immunosuppressants are incomplete and in some cases contradictory. The early use of steroid-sparing immunosuppressants is recommended for TAK, although the number of randomized placebo-controlled trials is limited and no steroid-sparing treatment has yet been approved for TAK. For both diseases there is still a great need for modern and safe steroid-sparing treatment that effectively treats vasculitis, prevents damage and enables adequate disease monitoring. This article provides an overview of the current study situation and possible future treatment options for GCA and TAK.

[Polymyalgia rheumatica: What's new?]

Currently, only 25% of all polymyalgia rheumatica (PMR) patients are referred to specialists. An expert committee has recently recommended confirmation of diagnosis by specialist care. This can help to avoid misdiagnoses and hospital stays and can result in lower glucocorticoid doses.Using ultrasound, magnetic resonance imagining (MRI), or positron emission tomography-computed tomography (PET-CT), typical periarticular inflammatory changes are observed, especially in the shoulder and pelvic girdle area. However, for clinical use, ultrasound is usually sufficient.In 20-25% of newly diagnosed PMR patients without symptoms of giant cell arteritis (GCA), GCA can be detected through vascular ultrasound. These patients require higher glucocorticoid doses in analogy to GCA therapy. There is growing awareness of a joint GCA-PMR spectrum disease.Glucocorticoids remain the primary treatment. The interleukin-6 inhibitor Sarilumab has recently been approved in the USA for patients with recurrent PMR. Studies have also demonstrated the effectiveness of Tocilizumab in PMR.

The pipeline of immunomodulatory therapies in polymyalgia rheumatica and giant cell arteritis: A systematic review of clinical trials

INTRODUCTION

The objective of this systematic review was to provide an overview of current developments and potentially available therapeutic options for polymyalgia rheumatic (PMR) and giant cell arteritis (GCA), in the coming years.

METHODS

We conducted a systematic review of 17 national and international clinical trial databases for all disease-modifying anti-rheumatic drugs (DMARDs) for PMR and GCA that are already marketed, in clinical development or withdrawn. The search was performed on January 2024, with the keywords "polymyalgia rheumatica" and "giant cell arteritis". For each molecule, we only considered the study at the most advanced stage of clinical development.

RESULTS

For PMR, a total of 15 DMARDs were identified: 2 conventional synthetic DMARDs (csDMARDs), 11 biologic DMARDs (bDMARDs) and 2 targeted synthetic DMARDs (tsDMARDs). For GCA, 18 DMARDs were identified: 2 csDMARDs, 14 bDMARDs and 2 tsDMARDs. Currently, there are only 2 approved corticosteroid-sparing therapies in these diseases, which both target the IL-6 signaling pathway, namely tocilizumab in GCA and sarilumab in PMR. Most of the molecules in current development are repurposed from from other conditions and clinical research in PMR/GCA seems to be mostly driven by the potential to repurpose existing treatments rather than by translational research.

CONCLUSION

This systematic review identified 23 DMARDs evaluated for PMR and GCA: 3 csDMARDs, 17 bDMARDs and 3 tsDMARDs. Several promising treatments are likely to be marketed in the coming years.

Diagnosing vasculitis with ultrasound: findings and pitfalls

Rheumatologists are increasingly utilizing ultrasound for suspected giant cell arteritis (GCA) or Takayasu arteritis (TAK). This enables direct confirmation of a suspected diagnosis within the examination room without further referrals. Rheumatologists can ask additional questions and explain findings to their patients while performing ultrasound, preferably in fast-track clinics to prevent vision loss. Vascular ultrasound for suspected vasculitis was recently integrated into rheumatology training in Germany. New European Alliance of Associations for Rheumatology recommendations prioritize ultrasound as the first imaging tool for suspected GCA and recommend it as an imaging option for suspected TAK alongside magnetic resonance imaging, positron emission tomography and computed tomography. Ultrasound is integral to the new classification criteria for GCA and TAK. Diagnosis is based on consistent clinical and ultrasound findings. Inconclusive cases require histology or additional imaging tests. Robust evidence establishes high sensitivities and specificities for ultrasound. Reliability is good among experts. Ultrasound reveals a characteristic non-compressible 'halo sign' indicating intima-media thickening (IMT) and, in acute disease, artery wall oedema. Ultrasound can further identify stenoses, occlusions and aneurysms, and IMT can be measured. In suspected GCA, ultrasound should include at least the temporal and axillary arteries bilaterally. Nearly all other arteries are accessible except the descending thoracic aorta. TAK mostly involves the common carotid and subclavian arteries. Ultrasound detects subclinical GCA in over 20% of polymyalgia rheumatica (PMR) patients without GCA symptoms. Patients with silent GCA should be treated as GCA because they experience more relapses and require higher glucocorticoid doses than PMR patients without GCA. Scores based on intima-thickness (IMT) of temporal and axillary arteries aid follow-up of GCA, particularly in trials. The IMT decreases more rapidly in temporal than in axillary arteries. Ascending aorta ultrasound helps monitor patients with extracranial GCA for the development of aneurysms. Experienced sonologists can easily identify pitfalls, which will be addressed in this article.

Cranial involvement in giant cell arteritis

Since its first clinical description in 1890, extensive research has advanced our understanding of giant cell arteritis, leading to improvements in both diagnosis and management for affected patients. Imaging studies have shown that the disease frequently extends beyond the typical cranial arteries, also affecting large vessels such as the aorta and its proximal branches. Meanwhile, advances in comprehending the underlying pathophysiology of giant cell arteritis have given rise to numerous potential therapeutic agents, which aim to minimise the need for glucocorticoid treatment and prevent flares. Classification criteria for giant cell arteritis, as well as recommendations for management, imaging, and treat-to-target have been developed or updated in the last 5 years, and current research encompasses a broad spectrum covering basic, translational, and clinical research. In this Series paper, we aim to discuss the current understanding of giant cell arteritis with cranial manifestations, describe the clinical approach to this condition, and explore future directions in research and patient care.