Sarilumab for the treatment of ankylosing spondylitis: results of a Phase II, randomised, double-blind, placebo-controlled study (ALIGN)

Natural products as IL-6 inhibitors for inflammatory diseases: Synthetic and SAR perspective

Interleukin-6 (IL-6), a pleiotropic cytokine, plays a pivotal role in the pathophysiology of various diseases including diabetes, atherosclerosis, Alzheimer's disease, multiple myeloma, rheumatoid arthritis, and prostate cancer. The signaling pathways associated with IL-6 offer promising targets for therapeutic interventions in inflammatory diseases and IL-6-dependent tumors. Although certain anti-IL-6 monoclonal antibodies are currently employed clinically, their usage is hampered by drawbacks such as high cost and potential immunogenicity, limiting their application. Thus, the imperative arises to develop novel small non-peptide molecules acting as IL-6 inhibitors. Various natural products derived from diverse sources have been investigated for their potential to inhibit IL-6 activity. Nevertheless, these natural products remain inadequately explored in terms of their structure-activity relationships. In response, our review aims to provide syntheses and structure activity perspective of natural IL-6 inhibitors. The comprehensive amalgamation of information presented in this review holds the potential to serve as a foundation for forthcoming research endeavors by medicinal chemists, facilitating the design of innovative IL-6 inhibitors to address the complexities of inflammatory diseases.

Unmet need in rheumatology: reports from the Advances in Targeted Therapies meeting, 2023

The Advances in Targeted Therapies meets annually, convening experts in the field of rheumatology to both provide scientific updates and identify existing scientific gaps within the field. To review the major unmet scientific needs in rheumatology. The 23rd annual Advances in Targeted Therapies meeting convened with more than 100 international basic scientists and clinical researchers in rheumatology, immunology, infectious diseases, epidemiology, molecular biology and other specialties relating to all aspects of immune-mediated inflammatory diseases. We held breakout sessions in five rheumatological disease-specific groups including: rheumatoid arthritis (RA), psoriatic arthritis (PsA), axial spondyloarthritis (axSpa), systemic lupus erythematosus (SLE), systemic sclerosis (SSc) and vasculitis, and osteoarthritis (OA). In each group, experts were asked to identify and prioritise current unmet needs in clinical and translational research. An overarching theme across all disease states is the continued need for clinical trial design innovation with regard to therapeutics, endpoint and disease endotypes. Within RA, unmet needs comprise molecular classification of disease pathogenesis and activity, pre-/early RA strategies, more refined pain profiling and innovative trials designs to deliver on precision medicine. Continued scientific questions within PsA include evaluating the genetic, immunophenotypic, clinical signatures that predict development of PsA in patients with psoriasis, and the evaluation of combination therapies for difficult-to-treat disease. For axSpA, there continues to be the need to understand the role of interleukin-23 (IL-23) in pathogenesis and the genetic relationship of the IL-23-receptor polymorphism with other related systemic inflammatory diseases (eg, inflammatory bowel disease). A major unmet need in the OA field remains the need to develop the ability to reliably phenotype and stratify patients for inclusion in clinical trials. SLE experts identified a number of unmet needs within clinical trial design including the need for allowing endpoints that reflect pharmacodynamic/functional outcomes (eg, inhibition of type I interferon pathway activation; changes in urine biomarkers). Lastly, within SSc and vasculitis, there is a lack of biomarkers that predict response or disease progression, and that allow patients to be stratified for therapies. There remains a strong need to innovate clinical trial design, to identify systemic and tissue-level biomarkers that predict progression or response to therapy, endotype disease, and to continue developing therapies and therapeutic strategies for those with treatment-refractory disease. This document, based on expert consensus, should provide a roadmap for prioritising scientific endeavour in the field of rheumatology.

Impact of immune regulation and differentiation dysfunction of mesenchymal stem cells on the disease process in ankylosing spondylitis and prospective analysis of stem cell transplantation therapy

Ankylosing spondylitis (AS) is a rheumatic bone and joint disease caused by inflammation, erosion, and pathological bone formation. The pathological features of chronic inflammation, bone destruction, and pathological ossification occur due to the disruption of the body's immune regulation and altered bone remodeling balance. Mesenchymal stem cells (MSCs) have multidirectional differentiation potential and immunomodulatory functions and play an important role in immune regulation and bone formation. The immune regulation and osteogenic capacity of MSCs in AS are altered by factors such as genetic background, internal environment, infection, and mechanical forces that drive disease development. This review further evaluates the role of MSCs dysfunction in inflammation and pathological bone formation by analyzing the effects of the above-mentioned factors on MSCs function and also looks forward to the prospects of MSCs in treating AS, providing some ideas for an in-depth study of inflammation and ectopic ossification.

KEY MESSAGES

Osteoimmunology of Spondyloarthritis

The mechanisms underlying the development of bone damage in the context of spondyloarthritis (SpA) are not completely understood. To date, a considerable amount of evidence indicates that several developmental pathways are crucially involved in osteoimmunology. The present review explores the biological mechanisms underlying the relationship between inflammatory dysregulation, structural progression, and osteoporosis in this diverse family of conditions. We summarize the current knowledge of bone biology and balance and the foundations of bone regulation, including bone morphogenetic protein, the Wnt pathway, and Hedgehog signaling, as well as the role of cytokines in the development of bone damage in SpA. Other areas surveyed include the pathobiology of bone damage and systemic bone loss (osteoporosis) in SpA and the effects of pharmacological treatment on focal bone damage. Lastly, we present data relative to a survey of bone metabolic assessment in SpA from Italian bone specialist rheumatology centers. The results confirm that most of the attention to bone health is given to postmenopausal subjects and that the aspect of metabolic bone health may still be underrepresented. In our opinion, it may be the time for a call to action to increase the interest in and focus on the diagnosis and management of SpA.

Have Therapeutics Enhanced Our Knowledge of Axial Spondyloarthritis?

PURPOSE OF REVIEW

An overview of how the treatment landscape of axial spondyloarthritis (axSpA) has shaped our understanding of the disease.

RECENT FINDINGS

Prior to the millennium, non-steroidal anti-inflammatory drugs (NSAIDs) were the only treatment for axSpA, yet only 30% of patients responded and many developed side effects. In 2003, the first biological disease-modifying drug (bDMARD) was licensed for axSpA which substantially improved outcomes in comparison to NSAIDs. In 2022, there are now several bDMARDs for axSpA; however, they too are not universally efficacious in treating axial inflammation and may have deleterious effects on extramusculoskeletal manifestations. Nevertheless, successful or not, each bDMARD gives invaluable insight into axSpA immunobiology. This review discusses how much we have learned from the use of bDMARDs in axSpA, how this has redefined our understanding of the disease, and how we might use this knowledge to develop new and better treatments for axSpA in the future.

Efficacy and safety of IL inhibitors, TNF-α inhibitors, and JAK inhibitors in patients with ankylosing spondylitis: a systematic review and Bayesian network meta-analysis

Background

Biologics and Janus kinase (JAK) inhibitors are commonly used to improve ankylosing spondylitis (AS) symptoms if conventional treatments are ineffective or unsuitable. This systematic review aimed to compare the therapeutic effects and safety of JAK inhibitors, tumor necrosis factor-alpha (TNF-α) inhibitors, and interleukin (IL) inhibitors in patients with AS.

Methods

We retrieved literature from various databases including Web of Science, Cochrane, Embase, PubMed, China National Knowledge Infrastructure, Weipu Journal Database, SinoMed, and WanFang Data up to February 1, 2023, and evaluated the quality of the included RCTs using the Cochrane risk-of-bias tool. R 4.1.3, STATA 15.1 were employed for network meta-analyses.

Results

We identified 48 eligible articles including 8,937 patients. Ten articles were rated as "low risk", 5 as "high risk", and the others as "some concerns". In terms of efficacy, IL-17, IL-6, and JAK inhibitors were compared with TNF-α inhibitors in ASAS20 (RR =0.81, 95% CI: 0.66-0.98; RR =0.57, 95% CI: 0.35-0.95; RR =0.77, 95% CI: 0.60-0.99). IL-6 inhibitors were compared with TNF-α inhibitors in ASAS5/6 (RR =0.39, 95% CI: 0.16-0.98). IL-23, JAK inhibitors were compared with TNF-α inhibitors in BASDAI50 (RR =0.35, 95% CI: 0.20-0.60; RR =0.70, 95% CI: 0.49-0.98). IL-17 inhibitors were compared with IL-23 and IL-6 inhibitors in BASFI (MD =-1.05, 95% CI: -1.65--0.51; MD =-1.46, 95% CI: -2.02--0.97). In terms of safety, IL-6 inhibitors were compared with JAK, TNF-α inhibitors in AEs (RR =1.38, 95% CI: 1.06-1.88; RR =1.30, 95% CI: 1.01-1.70).

Conclusions

TNF-α inhibitors are significantly superior to both IL and JAK inhibitors, and may be the preferable option to deal with the rapid progression of AS and severe functional limitations. IL-17 inhibitors may better improve the BASDAI50 response compared with JAK, IL-23, and TNF-α inhibitors. The efficacy and safety of IL-6 inhibitors are inferior to other types of drugs, indicating the low efficacy and high risk of IL-6 inhibitors.

Management of Axial Disease in Patients With Psoriatic Arthritis: An Updated Literature Review Informing the 2021 GRAPPA Treatment Recommendations

OBJECTIVE

Axial involvement in patients with psoriatic arthritis (PsA) is a common subset of this condition, but a unanimous definition has yet to be established. It has been defined by using different criteria, ranging from the presence of at least unilateral grade 2 sacroiliitis to those used for ankylosing spondylitis (AS), or simply the presence of inflammatory low back pain (IBP). Our aim was to identify and evaluate the efficacy of therapeutic interventions for treatment of axial disease in PsA.

METHODS

This systematic review is an update of the axial PsA (axPsA) domain of the treatment recommendations project by the Group for Research and Assessment of Psoriasis and Psoriatic Arthritis (GRAPPA).

RESULTS

The systematic review of the literature showed that new biologic and targeted synthetic disease-modifying antirheumatic drug classes, namely interleukin (IL)-17A and Janus kinase inhibitors, could be considered for the treatment of axPsA. This would be in addition to previously recommended treatments such as nonsteroidal antiinflammatory drugs, physiotherapy, simple analgesia, and tumor necrosis factor inhibitors. Conflicting evidence still remains regarding the use of IL-12/23 and IL-23 inhibitors.

CONCLUSION

Further studies are needed for a better understanding of the treatment of axPsA, as well as validated outcome measures.

Emerging therapies for the treatment of spondyloarthritides with focus on axial spondyloarthritis

INTRODUCTION

Spondyloarthritides (SpA) such as axial spondyloarthritis (axSpA) including ankylosing spondylitis (AS) and psoriatic arthritis (PsA) including psoriasis are chronic immune-mediated disorders with involvement of tumor necrosis factor (TNF), interleukin (IL)-17 cytokines, and janus kinases (JAK) in their pathogenesis, with IL-23 clearly also playing a role in psoriasis, PsA, and chronic inflammatory bowel diseases.

AREAS COVERED

In this narrative review, we focus on a biologic disease modifying anti-rheumatic drug (bDMARD), the bispecific IL-17A and IL-17 F inhibitor bimekizumab, and a targeted synthetic (ts) DMARD, the JAK inhibitor (i) filgotinib - emerging agents for the treatment of axSpA. Upadacitinib, another JAKi that has recently been reviewed intensively by us is already approved for axSpA and PsA in Europe.

EXPERT OPINION

In contrast to inhibition of IL-17, JAKi also work in rheumatoid arthritis (RA), while agents inhibiting IL-17 are not, even though some effect may be there. Indeed, 4 JAKi including filgotinib are approved for RA. There are several head-to-head trials with bimekizumab in plaque psoriasis. The last one showed that the bispecific inhibition of IL-17A and IL-17 F with bimekizumab may indeed be superior to inhibition of IL-17A alone with 300 mg secukinumab (usual dosage). Whether this is also the case for treatment of axSpA and PsA remains to be shown.

Therapeutic Utility and Adverse Effects of Biologic Disease-Modifying Anti-Rheumatic Drugs in Inflammatory Arthritis

Targeting specific pathologic pro-inflammatory cytokines or related molecules leads to excellent therapeutic effects in inflammatory arthritis, including rheumatoid arthritis, ankylosing spondylitis, and psoriatic arthritis. Most of these agents, known as biologic disease-modifying anti-rheumatic drugs (bDMARDs), are produced in live cell lines and are usually monoclonal antibodies. Several types of monoclonal antibodies target different pro-inflammatory cytokines, such as tumor necrosis factor-α, interleukin (IL)-17A, IL-6, and IL-23/12. Some bDMARDs, such as rituximab and abatacept, target specific cell-surface molecules to control the inflammatory response. The therapeutic effects of these bDMARDs differ in different forms of inflammatory arthritis and are associated with different adverse events. In this article, we summarize the therapeutic utility and adverse effects of bDMARDs and suggest future research directions for developing bDMARDs.

A systematic literature review informing the consensus statement on efficacy and safety of pharmacological treatment with interleukin-6 pathway inhibition with biological DMARDs in immune-mediated inflammatory diseases

Objectives

Informing an international task force updating the consensus statement on efficacy and safety of biological disease-modifying antirheumatic drugs (bDMARDs) selectively targeting interleukin-6 (IL-6) pathway in the context of immune-mediated inflammatory diseases.

Methods

A systematic literature research of all publications on IL-6 axis inhibition with bDMARDs published between January 2012 and December 2020 was performed using MEDLINE, EMBASE and Cochrane CENTRAL databases. Efficacy and safety outcomes were assessed in clinical trials including their long-term extensions and observational studies. Meeting abstracts from ACR, EULAR conferences and results on clinicaltrials.gov were taken into consideration.

Results

187 articles fulfilled the inclusion criteria. Evidence for positive effect of IL-6 inhibition was available in various inflammatory diseases such as rheumatoid arthritis, juvenile idiopathic arthritis, giant cell arteritis, Takayasu arteritis, adult-onset Still’s disease, cytokine release syndrome due to chimeric antigen receptor T cell therapy and systemic sclerosis-associated interstitial lung disease. Newcomers like satralizumab and anti-IL-6 ligand antibody siltuximab have expanded therapeutic approaches for Castleman’s disease and neuromyelitis optica, respectively. IL-6 inhibition did not provide therapeutic benefits in psoriatic arthritis, ankylosing spondylitis and certain connective tissue diseases. In COVID-19, tocilizumab (TCZ) has proven to be therapeutic in advanced disease. Safety outcomes did not differ from other bDMARDs, except higher risks of diverticulitis and lower gastrointestinal perforations. Inconsistent results were observed in several studies investigating the risk for infections when comparing TCZ to TNF-inhibitors.

Conclusion

IL-6 inhibition is effective for treatment of several inflammatory diseases with a safety profile that is widely comparable to other bDMARDs.

The role of cytokines and their antagonists in the treatment of COVID-19 patients

The coronavirus disease 2019 (COVID-19) has various presentations, of which immune dysregulation or the so-called cytokine storm syndrome (COVID-CSS) is prominent. Even though cytokines are vital regulators of body immunoinflammatory responses, their exaggerated release can be harmful. This hyperinflammatory response is more commonly observed during severe COVID-19 infections, caused by the excessive release of pro-inflammatory cytokines, such as interleukin-1 (IL-1), IL-6, IL-8, tumour necrosis factor, granulocyte-macrophage colony-stimulating factor, and interferon-gamma, making their blockers and antagonists of great interest as therapeutic options in this condition. Thus, the pathophysiology of excessive cytokine secretion is outlined, and their most important blockers and antagonists are discussed, mainly focussing on tocilizumab, an interleukin-6 receptor blocker approved to treat severe COVID-19 infections.

Hyper/neuroinflammation in COVID-19 and suicide etiopathogenesis: Hypothesis for a nefarious collision?

Accumulating scientific and clinical evidence highlighted pathological hyperinflammation as a cardinal feature of SARS-CoV-2 infection and acute COVID-19 disease. With the emergence of long COVID-19 syndrome, several chronic health consequences, including neuropsychiatric sequelae, have gained attention from the public and medical communities. Since inflammatory mediators have also been accredited as putative biomarkers of suicidal ideations and behaviors, hyper- and neuroinflammation might share some colliding points, overlapping and being interconnected in the context of COVID-19. This review aims to provide a summary of current knowledge on the molecular and cellular mechanisms of COVID-19-associated hyper/neuroinflammation with focus on their relevance to the inflammatory hypothesis of suicide development. Subsequently, strategies to alleviate COVID-19 hyper/neuroinflammation by immunomodulatory agents (many of which at experimental stages) as well as psychopharmacologic/psychotherapeutic approaches are also mentioned. While suicide risk in COVID-19 survivors - until now little known - needs further analysis through longitudinal studies, current observations and mechanistic postulates warrant additional attention to this possibly emerging mental health concern.

No Significant Effects of IL-23 on Initiating and Perpetuating the Axial Spondyloarthritis: The Reasons for the Failure of IL-23 Inhibitors

Axial spondyloarthritis (axSpA) is comprised of ankylosing spondylitis (AS) and non-radiographic axSpA. In recent years, the involvement of the interleukin (IL)-23/IL-17 axis in the pathophysiology of axSpA has been widely proposed. Since IL-23 is an upstream activating cytokine of IL-17, theoretically targeting IL-23 should be effective in axSpA, especially after the success of the treatment with IL-17 blockers in the disorder. Unfortunately, IL-23 blockade did not show meaningful efficacy in clinical trials of AS. In this review, we analyzed the possible causes of the failure of IL-23 blockers in AS: 1) the available data from an animal model is not able to support that IL-23 is involved in a preclinical rather than clinical phase of axSpA; 2) Th17 cells are not principal inflammatory cells in the pathogenesis of axSpA; 3) IL-17 may be produced independently of IL-23 in several immune cell types other than Th17 cells in axSpA; 4) no solid evidence supports IL-23 as a pathogenic factor to induce enthesitis and bone formation. Taken together, IL-23 is not a principal proinflammatory cytokine in the pathogenesis of axSpA.

Monocytes and Macrophages in Spondyloarthritis: Functional Roles and Effects of Current Therapies

Spondyloarthritis (SpA) is a family of chronic inflammatory diseases, being the most prevalent ankylosing spondylitis (AS) and psoriatic arthritis (PsA). These diseases share genetic, clinical and immunological features, such as the implication of human leukocyte antigen (HLA) class I molecule 27 (HLA-B27), the inflammation of peripheral, spine and sacroiliac joints and the presence of extra-articular manifestations (psoriasis, anterior uveitis, enthesitis and inflammatory bowel disease). Monocytes and macrophages are essential cells of the innate immune system and are the first line of defence against external agents. In rheumatic diseases including SpA, the frequency and phenotypic and functional characteristics of both cell types are deregulated and are involved in the pathogenesis of these diseases. In fact, monocytes and macrophages play key roles in the inflammatory processes characteristics of SpA. The aim of this review is analysing the characteristics and functional roles of monocytes and macrophages in these diseases, as well as the impact of different current therapies on these cell types.

Prospective multicentre study of experience in real-world clinical practice in monitoring reported outcome measures (PROMs) of patient with a diagnosis of psoriatic and/or spondyloarthritis and initiating treatment with secukinumab

OBJECTIVE

To analyse the effect of secukinumab on self-reported variables of patients diagnosed with psoriatic arthritis and/or ankylosing spondylitis in relation to their health status, pain, fatigue, sleep and quality of life.

METHODS

A six-month, observational, longitudinal, prospective, multicentre study was conducted with 39 patients who initiated treatment with secukinumab as therapy for psoriatic arthritis and/or spondylitis. The main variables were changes in patient-reported measures and they were evaluated by means of the questionnaires: FACIT-fatigue, Insomnia Severity Index, EuroQol-3L-5D and PsAQoL. In addition, depending on the type of disease (peripheral psoriasis or spondyloarthritis) the DAS28 with ESR or the BASDAI were calculated, respectively.

RESULTS

Levels of fatigue, moderate and severe insomnia significantly reduced after 6 months of treatment with secukinumab. At the same time, patient-reported quality of life increased significantly (P = .006). Data on pain and discomfort also show significant improvement after the treatment.

CONCLUSIONS

Patients with psoriatic arthritis and/or ankylosing spondylitis who start treatment with secukinumab show improvement at 6 months in all effect sizes of the treatment, particularly in sleep, fatigue and quality of life. Furthermore, patient-reported outcome measures are of additional clinical value and allow more accurate and closer assessment of their real status of health and well-being.

Pathogenesis of Axial Spondyloarthritis - Sources and Current State of Knowledge

Scientific breakthroughs have culminated in the development of the spondyloarthritis (SpA) concept as a family of rheumatic diseases, distinct from rheumatoid arthritis. The demonstration of inflammatory lesions in the sacroiliac joints and spine of patients with axial symptoms of SpA who lacked radiographic features of ankylosing spondylitis (AS) helped refine the SpA concept. Axial SpA includes patients with AS and patients with axial symptoms previously categorized as undifferentiated SpA. This review examines the sources of knowledge that inform axial SpA pathogenesis, highlighting current limitations, and a basic working model of axial SpA pathogenesis.

Axial spondyloarthritis

Axial spondyloarthritis (axSpA) encompasses both radiographic and non-radiographic axSpA. It is a chronic inflammatory disease with a predilection for involving the axial skeleton. The most common presenting symptoms are chronic back pain and spinal stiffness but peripheral and extra-musculoskeletal manifestations occur also frequently. The diagnosis of axSpA relies on the recognition of a clinical pattern of the disease, based on clinical, laboratory and imaging features. The Assessment in SpondyloArthritis international Society classification criteria for axSpA are valid and well implemented for research purposes. Sustained disease activity, measured by validated tools such as the Ankylosing Spondylitis Disease Activity Score, leads to irreversible structural damage and poor functioning and therefore should be abrogated. As part of the management algorithm, non-steroidal anti-inflammatory drugs remain as the first line of pharmacological treatment besides physiotherapy. As a second line, tumour necrosis factor inhibitor and interleukin-17 inhibitor are available but recently Janus kinase inhibitors have also shown efficacy in improving symptoms of the disease.

Unravelling the broader complexity of IL-6 involvement in health and disease

The classification of interleukin-6 (IL-6) as a pro-inflammatory cytokine undervalues the biological impact of this cytokine in health and disease. With broad activities affecting the immune system, tissue homeostasis and metabolic processes, IL-6 displays complex biology. The significance of these involvements has become increasingly important in clinical settings where IL-6 is identified as a prominent target for therapy. Here, clinical experience with IL-6 antagonists emphasises the need to understand the context-dependent properties of IL-6 within an inflammatory environment and the anticipated or unexpected consequences of IL-6 blockade. In this review, we will describe the immunobiology of IL-6 and explore the gamut of IL-6 bioactivity affecting the clinical response to biological drugs targeting this cytokine pathway.

Effect of interleukin-17A inhibitor in Japanese patients with psoriatic arthritis compared with tumor necrosis factor-alpha inhibitor

OBJECTIVES

The patient of severe psoriatic arthritis (PsA) is mainly treated with oral methotrexate, ciclosporin, and anti-tumor necrosis factor-alpha inhibitors (TNFi). Recently, anti-interleukin-17A inhibitors (IL-17Ai) have been used in the treatment of PsA. This study aimed to evaluate the efficacy and safety of IL-17Ai in Japanese patients with PsA compared with those of TNFi.

METHODS

This was a longitudinal and retrospective study. The study population included 31 Japanese patients with PsA. All enrolled patients fulfilled the Classification Criteria for Psoriatic Arthritis. All patients were treated with TNFi or IL-17Ai. The assessed clinical manifestations were C-reactive protein (CRP)-based Disease Activity Score in 28 Joints (DAS28-CRP), disease activity in psoriatic arthritis (DAPSA), 20% achievement of American College of Rheumatology core set, swollen joint count (SJC), tender joint count (TJC), and visual analog scale (VAS). Functional ability of patients with PsA was analyzed using the modified health assessment questionnaire (mHAQ) score. We evaluated the parameters at baseline and weeks 12, 24, and 52.

RESULTS

The change in SJC, TJC, VAS, mHAQ, and DAPSA had no significant difference at weeks 12, 24, and 52. The improvements of CRP and DAS28-CRP were significantly higher in TNFi group only at week 12. The biologics retention rate was significantly higher in TNFi group by the log-rank test. No critical adverse events occurred.

CONCLUSIONS

Our study presented that IL-17Ai had treatment effects comparable to TNFi. IL-17Ai might have the potential to become an alternative to the previous drug, but more large-scale studies are expected.

An update on the pathogenic role of IL-6 in rheumatic diseases

Interleukin (IL)-6 is a pleiotropic cytokine that is involved in the pathogenesis of various rheumatic diseases. Direct inhibition of the IL-6 pathway by an anti-IL-6 receptor or inhibiting the ligand itself has proved to be efficacious in the treatment of these diseases. Juvenile idiopathic arthritis, adult-onset Still's disease, large vessel vasculitis including giant cell arteritis and Takayasu disease, systemic sclerosis, and polymyalgia rheumatica respond well to IL-6 inhibition as expected. However, no clinically meaningful effect has been observed with regard to IL-6 blockade in ankylosing spondylitis, psoriatic arthritis, and systemic lupus erythematosus. This review discusses the current state of IL-6 targeting approaches in various rheumatic diseases other than rheumatoid arthritis.

Promising Treatment Options for Axial Spondyloarthritis: An Overview of Experimental Pharmacological Agents

Axial spondyloarthritis (axSpA) is a chronic inflammatory condition that predominantly affects the axial skeleton. All patients receive conservative management measures which include physiotherapy, patient education and use of nonsteroidal anti-inflammatory drugs (NSAIDs). Those with significant active disease will require escalation of their treatment with the use of biologics. Currently, there are five approved TNF inhibitors and two approved IL-17 inhibitors for use in axSpA. However, despite this up to 40% of patients do not respond or are intolerant to current available treatment. This leaves a significant number of patients with uncontrolled disease and unmet need for additional therapies. Though many drug classes have been trialed for axSpA they show poor efficacy; however, over the last few years there are three which demonstrate much greater promise as novel therapies for axSpA, these include dual neutralization of IL-17A and IL-17F, Janus kinase (JAK) inhibitors, and granulocyte-macrophage colony-stimulating factor (GM-CSF) inhibitors. This article reviews the evidence for these novel emerging therapeutic options for axSpA.

Cytokine Storm Syndrome in SARS-CoV-2 Infections: A Functional Role of Mast Cells

Cytokine storm syndrome is a cascade of escalated immune responses disposing the immune system to exhaustion, which might ultimately result in organ failure and fatal respiratory distress. Infection with severe acute respiratory syndrome-coronavirus-2 can result in uncontrolled production of cytokines and eventually the development of cytokine storm syndrome. Mast cells may react to viruses in collaboration with other cells and lung autopsy findings from patients that died from the coronavirus disease that emerged in 2019 (COVID-19) showed accumulation of mast cells in the lungs that was thought to be the cause of pulmonary edema, inflammation, and thrombosis. In this review, we present evidence that a cytokine response by mast cells may initiate inappropriate antiviral immune responses and cause the development of cytokine storm syndrome. We also explore the potential of mast cell activators as adjuvants for COVID-19 vaccines and discuss the medications that target the functions of mast cells and could be of value in the treatment of COVID-19. Recognition of the cytokine storm is crucial for proper treatment of patients and preventing the release of mast cell mediators, as impeding the impacts imposed by these mediators could reduce the severity of COVID-19.

From Science to Success? Targeting Tyrosine Kinase 2 in Spondyloarthritis and Related Chronic Inflammatory Diseases

Spondyloarthritis (SpA) is a family of inflammatory arthritic diseases, which includes the prototypes of psoriatic arthritis and ankylosing spondylitis. SpA is commonly associated with systemic inflammatory diseases, such as psoriasis and inflammatory bowel disease. Immunological studies, murine models and the genetics of SpA all indicate a pathogenic role for the IL-23/IL-17 axis. Therapeutics targeting the IL-23/IL-17 pathway are successful at providing symptomatic relief, but may not provide complete protection against progression of arthritis. Thus there is still tremendous interest in the discovery of novel therapeutic targets for SpA. Tyrosine kinase 2 (TYK2) is a member of the Janus kinases, which mediate intracellular signaling of cytokines via signal transducer and activator of transcription (STAT) activation. TYK2 plays a crucial role in mediating IL-23 receptor signaling and STAT3 activation. A plethora of natural mutations in and around TYK2 have provided a wealth of data to associate this kinase with autoimmune/autoinflammatory diseases in humans. Induced and natural mutations in murine Tyk2 largely support human data; however, key inter-species differences exist, which means extrapolation of data from murine models to humans needs to be done with caution. Despite these reservations, novel selective TYK2 inhibitors are now proving successful in advanced clinical trials of inflammatory diseases. In this review, we will discuss TYK2 from basic biology to therapeutic targeting, with an emphasis on studies in SpA. Seminal studies uncovering the basic science of TYK2 have provided sound foundations for targeting it in SpA and related inflammatory diseases. TYK2 inhibitors may well be the next blockbuster therapeutic for SpA.

The role of IL-6 and IL-6 blockade in COVID-19

INTRODUCTION

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) induces a dysregulated hyperinflammatory response.

AREAS COVERED

Authors review evidence on IL-6 and IL-6 blockade in coronavirus disease 2019 (COVID-19) and discuss the pathophysiological and prognostic roles of this cytokine and the clinical impact of pharmacological blockade of IL-6 . The material includes original articles and reviews published from March 2020 to March 2021 and searched on PubMed, medRxiv, and bioRxiv.

EXPERT OPINION

IL-6 is one of the most prominent pro-inflammatory cytokines. Increased levels are recorded in COVID-19 patients, especially those with severe-to-critical disease. Evidence is accumulating on the relevance of IL-6 as a prognostic marker in COVID-19. Since IL-6 is a druggable target for several inflammatory diseases, pharmacological blockers of the IL-6 signaling pathway were repurposed to blunt the abnormal SARS-CoV-2-induced cytokine release. Data are limited to few randomized controlled trials that reported encouraging, though not conclusive, results, indicating the usefulness of IL-6 blockade early in the course of the disease in patients with hyperinflammation and no or limited organ damage. Further research is warranted to explore the role of IL-6 in different COVID-19 phenotypes and identify subgroups of patients who may mostly benefit from IL-6 pathway inhibition.

JAK Inhibitors for Axial Spondyloarthritis: What does the Future Hold?

PURPOSE OF REVIEW

To discuss the potential role of JAK inhibitors (JAKis) as a new therapeutic class for the treatment of axial spondyloarthritis (axSpA, including ankylosing spondylitis [AS] and non-radiographic axSpA [nr-axSpA]).

RECENT FINDINGS

A phase III randomized controlled trial of tofacitinib (a "pan JAKi") in patients with active AS was found to be superior to placebo in achieving the ASAS20 primary endpoint at week 16 (56.4% and 29.4%, p < 0.0001, phase II trials of AS). Upadacitinib, a JAK1 inhibitor, has also been evaluated in a phase III trial for its efficacy and safety in AS. The primary endpoint, ASAS40 at week 16, was reached by 52% of the patients randomized to upadacitinib and 26% of the patients receiving placebo (p = 0·0003). All the important secondary endpoints also improved with both agents. No new changes in their safety profile were noted. However, the more frequent occurrence of cardiovascular and cancer adverse events associated with tofacitinib than with TNFi observed in the very recent post-marketing "ORAL surveillance" safety study, the results of which were released on January 27, 2021, may lead to safety concerns swirling around the whole class of JAKis. JAKis seem to be effective in treating signs and symptoms of AS but have not been studied in nr-axSpA. Both tofacitinib and upadacitinib have been pre-registered with the FDA for the treatment of AS. Upadacitinib has just recently received approval for this indication in the European Union..

Novel approaches to develop biomarkers predicting treatment responses to TNF-blockers

Introduction: Chronic inflammatory diseases (CIDs) cause significant morbidity and are a considerable burden for the patients in terms of pain, impaired function, and diminished quality of life. Important progress in CID treatment has been obtained with biological therapies, such as tumor-necrosis-factor blockers. However, more than a third of the patients fail to respond to these inhibitors and are exposed to the side effects of treatment, without the benefits. Therefore, there is a strong interest in developing tools to predict response of patients to biologics. Areas covered: The authors searched PubMed for recent studies on biomarkers for disease assessment and prediction of therapeutic responses, focusing on the effect of TNF blockers on immune responses in spondyloarthritis (SpA), and other CID, in particular rheumatoid arthritis and inflammatory bowel disease. Conclusions will be drawn about the possible development of predictive biomarkers for response to treatment. Expert opinion: No validated biomarker is currently available to predict treatment response in CID. New insight could be generated through the development of new bioinformatic modeling approaches to combine multidimensional biomarkers that explain the different genetic, immunological and environmental determinants of therapeutic responses.

Cytokine "fine tuning" of enthesis tissue homeostasis as a pointer to spondyloarthritis pathogenesis with a focus on relevant TNF and IL-17 targeted therapies

A curious feature of axial disease in ankylosing spondylitis (AS) and related non-radiographic axial spondyloarthropathy (nrAxSpA) is that spinal inflammation may ultimately be associated with excessive entheseal tissue repair with new bone formation. Other SpA associated target tissues including the gut and the skin have well established paradigms on how local tissue immune responses and proven disease relevant cytokines including TNF and the IL-23/17 axis contribute to tissue repair. Normal skeletal homeostasis including the highly mechanically stressed entheseal sites is subject to tissue microdamage, micro-inflammation and ultimately repair. Like the skin and gut, healthy enthesis has resident immune cells including ILCs, γδ T cells, conventional CD4+ and CD8+ T cells and myeloid lineage cells capable of cytokine induction involving prostaglandins, growth factors and cytokines including TNF and IL-17 that regulate these responses. We discuss how human genetic studies, animal models and translational human immunology around TNF and IL-17 suggest a largely redundant role for these pathways in physiological tissue repair and homeostasis. However, disease associated immune system overactivity of these cytokines with loss of tissue repair “fine tuning” is eventually associated with exuberant tissue repair responses in AS. Conversely, excessive biomechanical stress at spinal enthesis or peripheral enthesis with mechanically related or degenerative conditions is associated with a normal immune system attempts at cytokine fine tuning, but in this setting, it is commensurate to sustained abnormal biomechanical stressing. Unlike SpA, where restoration of aberrant and excessive cytokine “fine tuning” is efficacious, antagonism of these pathways in biomechanically related disease may be of limited or even no value.

Ziltivekimab for Treatment of Anemia of Inflammation in Patients on Hemodialysis: Results from a Phase 1/2 Multicenter, Randomized, Double-Blind, Placebo-Controlled Trial

BACKGROUND

Patients with CKD who are on hemodialysis are hyporesponsive to erythropoiesis-stimulating agents (ESAs) because of anemia of inflammation. Interleukin-6 (IL-6) induced hepcidin expression is a key mediator of such inflammation.

METHODS

This phase 1/2, placebo-controlled trial assessed effects of ziltivekimab, a novel anti-IL-6 ligand antibody, in patients on hemodialysis with rs855791, a single nucleotide polymorphism of the TMPRSS6 gene that is hypothesized to heighten susceptibility to IL-6-mediated inflammatory effects. After a screening period documenting stable ESA and iron dosing, we randomized 61 patients with elevated IL-6 (≥4 pg/ml) to receive placebo or ziltivekimab (doses of 2, 6, or 20 mg), administered intravenously every 2 weeks for 12 weeks during hemodialysis. ESA dose adjustments were allowed after 4 weeks. We analyzed safety and effects on inflammation, iron metabolism, serum albumin, and anti-drug antibodies.

RESULTS

No patient experienced dose-limiting toxicity. Four patients (two each in the 6- and 20-mg cohorts) died of a treatment-emergent adverse event. Compared with patients receiving placebo, those receiving ziltivekimab experienced significantly greater reductions of high-sensitivity C-reactive protein, serum amyloid A, and fibrinogen from baseline to end of treatment. Median ESA usage decreased by 15,000, 15,000, or 33,000 IU/wk per patient in the 2-, 6-, and 20-mg ziltivekimab cohorts, respectively, compared with no change in the placebo group. We also noted significant dose responses for decreased ESA resistance index and increased serum iron, total iron binding capacity, transferrin saturation, and serum albumin.

CONCLUSIONS

Ziltivekimab significantly improved markers of inflammation, reduced ESA requirements, and increased serum albumin in patients on hemodialysis with inflammation and hyporesponsiveness to ESA therapy.

CLINICAL TRIAL REGISTRY NAME AND REGISTRATION NUMBER

Study to Assess the Safety, Pharmacokinetics, and Pharmacodynamics of Multiple Doses of COR-001, NCT02868229.

Skin manifestations in spondyloarthritis

Spondyloarthritides (SpA) like psoriatic arthritis, axial spondyloarthritis/ankylosing spondylitis, reactive arthritis and inflammatory bowel disease (IBD)-associated SpA can present with characteristic skin manifestations. These SpA-associated skin disorders may precede joint involvement, reflect a loss of efficacy of a current systemic treatment or can even be treatment associated. Cutaneous manifestations in SpA not only add additional morbidity with physical impact but also impose a psychosocial burden on affected patients. Psoriasis (PsO) - the main skin disease in SpA - has a variety of clinical presentations, including plaque-type PsO, inverse PsO, guttate PsO, erythrodermic PsO, nail PsO and pustular types. SpA associated with IBD presents with neutrophilic and granulomatous skin disorders, including pyoderma gangrenosum, hidradenitis suppurativa and cutaneous Crohn's disease. Reactive arthritides has a favourable prognosis and may feature keratoderma blenorrhagicum or balanitis circinatum as typical skin manifestations. Immunologically, SpA-associated skin diseases share interleukin (IL)-17 and IL-23 dysregulation but show distinctive genetic and immunological profiles. Therefore, they vary in their treatment responses to targeted therapies with biologicals or small molecules. In this review, we highlight the clinical presentation of skin manifestations in SpA and discuss therapeutic approaches in this interdisciplinary field.

Loss and gain of bone in spondyloarthritis: what drives these opposing clinical features?

The breadth of bone lesion types seen in spondyloarthritis is unprecedented in medicine and includes increased bone turnover, bone loss and fragility, osteitis, osteolysis and erosion, osteosclerosis, osteoproliferation of soft tissues adjacent to bone and spinal skeletal structure weakness. Remarkably, these effects can be present simultaneously in the same patient. The search for a potential unifying cause of effects on the skeleton necessarily focuses on inflammation arising from the dysregulation of immune response to microorganisms, particularly dysregulation of T_H17 lymphocytes, and the dysbiosis of established gut and other microbiota. The compelling notion that a common antecedent pathological mechanism affects existing bone and tissues with bone-forming potential (entheses), simultaneously with variable effect in the former but bone-forming in the latter, drives basic research forward and focuses our awareness on the effects on these bone mechanisms of the increasing portfolio of targeted immunotherapies used in the clinic.

Effect of biologic disease-modifying anti-rheumatic drugs targeting remission in axial spondyloarthritis: systematic review and meta-analysis

OBJECTIVES

To assess the efficacy of biologic DMARDs (bDMARDs) in achieving Assessment of Spondyloarthritis International Society partial remission (ASAS-PR) and/or Ankylosing Spondylitis Disease Activity Score inactive disease (ASDAS-ID), as remission-like surrogates, in axial SpA (axSpA).

METHODS

Data from randomized controlled trials (RCTs), including long-term extensions, were included. A systematic literature review was performed using the MEDLINE database (first search May 2018, updated February 2020) and PICO criteria according to Patients-adults with radiographic or non-radiographic axSpA; Intervention-any bDMARD; Comparator-placebo and/or any different drug; Outcomes-ASAS-PR and/or ASDAS-ID as primary or secondary endpoints. Meta-analysis was performed after assessment of the homogeneity of study designs, populations and outcomes.

RESULTS

After screening 155 references, a total of 22 RCTs and 28 long-term extensions were retrieved. ASAS-PR was the dominant remission-like definition used. Concerning TNF inhibitors, 14/17 RCTs provided evidence of efficacy in reaching remission at different time points: 12, 16, 24 and 28 weeks (ASAS-PR in 16-62% of patients and ASDAS-ID in 24-40% of patients). With a limited number of studies available, IL-17A inhibitors exhibited remission rates of 15-21% for ASAS-PR and 11-16% for ASDAS-ID at week 16. A meta-analysis regarding ASAS-PR was performed considering RCTs with a similar duration (12, 16 or 24 weeks). The relative risk for achieving remission was 3.864 (95% CI 2.937, 5.085).

CONCLUSION

bDMARDs have a clear impact in axSpA remission evaluated by ASAS-PR. Nevertheless, these data show an unmet need for improved reporting of remission-like outcomes.

Role of glucose metabolism in aggressive phenotype of fibroblast-like synoviocytes: Latest evidence and therapeutic approaches in rheumatoid arthritis

Glucose metabolism is considerably increased in inflamed joints of rheumatoid arthritis (RA) patients at early stages. Fibroblast-like synoviocytes (FLSs) activation and subsequent joint damage are linked with metabolic alterations, especially glucose metabolism. It has been shown that glucose metabolism is elevated in aggressive phenotype of FLS cells. In this regard, glycolytic blockers are able to reduce aggressiveness of the FLS cells resulting in decreased joint damage in various arthritis models. Besides, metabolic changes in immune and non-immune cells such as FLS can provide important targets for therapeutic intervention. Glycolytic enzymes such as hexokinase 2 (HK2), phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFKFB), and phosphoglycerate kinase (PGK) play essential roles in aggressive behavior of FLS cells. It has been documented that the HK2 enzyme is significantly upregulated in RA FLS cells, compared with osteoarthritis (OA) FLS cells. The HK2 is expressed in a few tissues and upregulated in the inflamed synovium of RA patients that makes it a potential target for RA treatment. Furthermore, HK2 has different roles in each cellular compartment, which offers another level of specificity and provides a specific target to reduce deleterious effects of inhibiting the enzyme in RA without affecting glycolysis in normal cells. Thus, targeting the HK2 enzyme might be an attractive potential selective target for arthritis therapy and safer than global glycolysis inhibition. Therefore, this review was aimed to summarize the current knowledge about glucose metabolism of FLS cells and suggest novel biomarkers, which are potential candidates for RA treatment.

Prospective multicentre study of experience in real-world clinical practice in monitoring reported outcome measures (PROMs) of patient with a diagnosis of psoriatic and/or spondyloarthritis and initiating treatment with secukinumab

OBJECTIVE

To analyse the effect of secukinumab on self-reported variables of patients diagnosed with psoriatic arthritis and/or ankylosing spondylitis in relation to their health status, pain, fatigue, sleep and quality of life.

METHODS

A six-month, observational, longitudinal, prospective, multicentre study was conducted with 39 patients who initiated treatment with secukinumab as therapy for psoriatic arthritis and/or spondylitis. The main variables were changes in patient-reported measures and they were evaluated by means of the questionnaires: FACIT-fatigue, Insomnia Severity Index, EuroQol-3L-5D and PsAQoL. In addition, depending on the type of disease (peripheral psoriasis or spondyloarthritis) the DAS28 with ESR or the BASDAI were calculated, respectively.

RESULTS

Levels of fatigue, moderate and severe insomnia significantly reduced after 6months of treatment with secukinumab. At the same time, patient-reported quality of life increased significantly (P=.006). Data on pain and discomfort also show significant improvement after the treatment.

CONCLUSIONS

Patients with psoriatic arthritis and/or ankylosing spondylitis who start treatment with secukinumab show improvement at 6months in all effect sizes of the treatment, particularly in sleep, fatigue and quality of life. Furthermore, patient-reported outcome measures are of additional clinical value and allow more accurate and closer assessment of their real status of health and well-being.

Potential Therapeutic Options for COVID-19: Current Status, Challenges, and Future Perspectives

The COVID-19 pandemic represents an unprecedented challenge for the researchers to offer safe, tolerable, and effective treatment strategies for its causative agent known as SARS-CoV-2. With the rapid evolution of the pandemic, even the off-label use of existing drugs has been restricted by limited availability. Several old antivirals, antimalarial, and biological drugs are being reconsidered as possible therapies. The effectiveness of the controversial treatment options for COVID-19 such as nonsteroidal antiinflammatory drugs, angiotensin 2 conversion enzyme inhibitors and selective angiotensin receptor blockers was also discussed. A systemic search in the PubMed, Science Direct, LitCovid, Chinese Clinical Trial Registry, and ClinicalTrials.gov data bases was conducted using the keywords "coronavirus drug therapy," passive immunotherapy for COVID-19', "convalescent plasma therapy," (CPT) "drugs for COVID-19 treatment," "SARS-CoV-2," "COVID-19," "2019-nCoV," "coronavirus immunology," "microbiology," "virology," and individual drug names. Systematic reviews, case presentations and very recent clinical guidelines were included. This narrative review summarizes the available information on possible therapies for COVID-19, providing recent data to health professionals.

Recent advances in managing axial spondyloarthritis

Axial spondyloarthritis (axSpA) is a chronic inflammatory rheumatic disease that predominantly affects the axial skeleton. The advent of biologic drugs has transformed the management of patients with axSpA. However, non-steroidal anti-inflammatory drugs remain the first-line drug treatment for axSpA. The optimal management of patients with axSpA requires a combination of pharmacological and non-pharmacological treatment modalities, namely exercise and physical therapy. This review looks at novel therapeutic options in patients with axSpA. It also summarises current evidence regarding radiographic progression and treat-to-target in axSpA.

Current therapies under investigation for COVID-19: potential COVID-19 treatments

In response to the outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), researchers are expeditiously searching for antiviral treatments able to alleviate the symptoms of infection, which can be life-threatening. Here, we provide a general overview of what is currently known about the structure and characteristic features of SARS-CoV-2, some of which could potentially be exploited for the purposes of antiviral therapy and vaccine development. This minireview also covers selected and noteworthy antiviral agents/supportive therapy out of hundreds of drugs that are being repurposed or tested as potential treatments for COVID-19, the disease caused by SARS-CoV-2.

Tuberculosis and targeted synthetic or biologic DMARDs, beyond tumor necrosis factor inhibitors

Patients with autoimmune rheumatic diseases (ARD) have an increased risk for tuberculosis (TB). The use of tumor necrosis factor inhibitors (TNFi) and glucocorticoids in these patients has been associated with an increased prevalence of latent TB reactivation. Over the last few years, several biologic disease-modifying anti-rheumatic drugs (bDMARDs), other than TNFi (e.g. rituximab, abatacept, tocilizumab, secukinumab) and targeted synthetic DMARDs (tsDMARDs) [e.g. apremilast, Janus kinase (JAK) inhibitors] have been used for the treatment of patients with ARD. For many of these drugs, especially the newer ones like JAK inhibitors or antibodies against interleukin (IL)-23, most data stem from randomized clinical trials and few are available from real life clinical experience. We sought to review the current evidence for TB risk in patients with ARD treated with tsDMARDs or bDMARDs, other than TNFi. It seems that some of these drugs are associated with a lower TB risk, indirectly compared with TNFi treatment. In fact, it appears that rituximab, apremilast and inhibitors of IL-17 and IL-23 might be safer, while more data are needed for JAK inhibitors. As seen in TNFi, risk for TB is more pronounced in TB-endemic areas. Screening for latent TB must precede initiation of any tsDMARDs or bDMARDs. The growing use of non-TNFi agents has raised the need for more real-life studies that would compare the risk for TB between TNFi and other treatment modalities for ARD. Knowledge about the TB-safety profile of these drugs could help in the decision of drug choice in patients with confirmed latent TB infection or in TB endemic areas.

SARS-CoV-2 and COVID-19: Is interleukin-6 (IL-6) the 'culprit lesion' of ARDS onset? What is there besides Tocilizumab? SGP130Fc

Since the outbreak of COVID-19 many studies have been published showing possible therapies, here the author discusses the end of stage disease related drugs, like Tocilizumab which is currently being used in ARDS patients. In some patients, disease progression leads to an enormous secretion of cytokines, known as cytokine storm, among those cytokines IL-6 plays an important role. Here the author shows how IL-6 has both pro and anti-inflammatory properties, depending on the pathway of transduction: soluble (trans-signaling) or membrane-related (classic signaling), and suggests how targeting only the pro-inflammatory pathway, with SGP130Fc, could be a better option then targeting them both. Other possible IL-6 pathway inhibitors such as Ruxolitinib and Baricinitib are then analyzed, underlying how they lack the benefit of targeting only the pro-inflammatory pathway.

Translating IL-6 biology into effective treatments

In 1973, IL-6 was identified as a soluble factor that is secreted by T cells and is important for antibody production by B cells. Since its discovery more than 40 years ago, the IL-6 pathway has emerged as a pivotal pathway involved in immune regulation in health and dysregulation in many diseases. Targeting of the IL-6 pathway has led to innovative therapeutic approaches for various rheumatic diseases, such as rheumatoid arthritis, juvenile idiopathic arthritis, adult-onset Still’s disease, giant cell arteritis and Takayasu arteritis, as well as other conditions such as Castleman disease and cytokine release syndrome. Targeting this pathway has also identified avenues for potential expansion into several other indications, such as uveitis, neuromyelitis optica and, most recently, COVID-19 pneumonia. To mark the tenth anniversary of anti-IL-6 receptor therapy worldwide, we discuss the history of research into IL-6 biology and the development of therapies that target IL-6 signalling, including the successes and challenges and with an emphasis on rheumatic diseases.

In this Perspective article, the authors recount the earliest stages of translational research into IL-6 biology and the subsequent development of therapeutic IL-6 pathway inhibitors for the treatment of autoimmune rheumatic diseases and potentially numerous other indications.

[Current treatment of axial spondylarthritis : Clinical efficacy]

Drug treatment in patients with axial spondylarthritis (axSpA) aims to modify symptoms and complaints and currently includes the substance groups of nonsteroidal anti-inflammatory drugs (NSAID) and biologicals (disease-modifying antirheumatic drugs, bDMARDS). Treatment with NSAIDs is the first line treatment according to international and national recommendations. Patients with persisting high disease activity despite continuous standard treatment with NSAIDs, should be treated with biologicals. In Germany treatment with tumor necosis factor (TNF) inhibitors or interleukin 17 inhibitor (secukinumab) are currently approved for treating patients with ankylosing spondylitis (AS). Treatment of patients with non-radiographic axSpA (nr-axSpA) is restricted to TNF inhibitors (except infliximab) in Germany. The efficacy and safety are documented for both substance groups; however, due to the longer time since approval longitudinal data for TNF inhibitors are more robust and the data contain information about switching within a substance group. Although overall retention rates of TNF inhibitors are similar despite the difference in formation of antidrug antibodies, data from cohorts provide information about long-term loss of efficacy, switching and also discontinuation strategies. In the meantime, various biosimilars have been approved for infliximab, etanercept and adalimumab. Conventional basic treatment (csDMARDs) and in particular intra-articular administration of glucocorticoids can only be prescribed for axSpA patients with peripheral arthritis.

The Brazilian Society of Rheumatology guidelines for axial spondyloarthritis - 2019

Spondyloarthritis is a group of chronic inflammatory systemic diseases characterized by axial and/or peripheral joints inflammation, as well as extra-articular manifestations. The classification axial spondyloarthritis is adopted when the spine and/or the sacroiliac joints are predominantly involved. This version of recommendations replaces the previous guidelines published in May 2013.A systematic literature review was performed, and two hundred thirty-seven studies were selected and used to formulate 29 recommendations answering 15 clinical questions, which were divided into four sections: diagnosis, non-pharmacological therapy, conventional drug therapy and biological therapy. For each recommendation the level of evidence supporting (highest available), the strength grade according to Oxford, and the degree of expert agreement (inter-rater reliability) is informed.These guidelines bring evidence-based information on clinical management of axial SpA patients, including, diagnosis, treatment, and prognosis.

A panoramic review of IL-6: Structure, pathophysiological roles and inhibitors

Interleukin-6 (IL-6) is a pleiotropic pro-inflammatory cytokine. Its deregulation is associated with chronic inflammation, and multifactorial auto-immune disorders. It mediates its biological roles through a hexameric complex composed of IL-6 itself, its receptor IL-6R, and glycoprotein 130 (IL-6/IL-6R/gp130). This complex, in turn, activates different signaling mechanisms (classical and trans-signaling) to execute various biochemical functions. The trans-signaling mechanism activates various pathological routes, like JAK/STAT3, Ras/MAPK, PI3K-PKB/Akt, and regulation of CD4+ T cells and VEGF levels, which cause cancer, multiple sclerosis, rheumatoid arthritis, anemia, inflammatory bowel disease, Crohn's disease, and Alzheimer's disease. Involvement of IL-6 in pathophysiology of these complex diseases makes it an important target for the treatment of these diseases. Though some anti-IL-6 monoclonal antibodies are being used clinically, but their high cost, only parenteral administration, and possibility of immunogenicity have limited their use, and warranted the development of novel small non-peptide molecules as IL-6 inhibitors. In the present report, all molecules reported in literature as IL-6 inhibitors have been classified as IL-6 production, IL-6R, and IL-6 signaling inhibitors. Reports available till date are critically studied to identify important and salient structural features common in these molecules. These analyses would assist medicinal chemists to design novel and potent IL-6 production and signaling inhibitors, through knowledge- and/or computer-based approaches, for the treatment of complex multifactorial diseases.