Efficacy and Safety of Subcutaneous and Intravenous Loading Dose Regimens of Secukinumab in Patients with Active Rheumatoid Arthritis: Results from a Randomized Phase II Study

From bench to bedside - is there a role of IL-17 drugs in rheumatoid arthritis?

INTRODUCTION

IL-17 has been described as a pro-inflammatory cytokine that is relevant in the seronegative spondylarthritides with IL-17 targeted therapies being licensed for their treatment.There is evidence to demonstrate that IL-17 is found in RA joints and contributes to the pro-inflammatory cascade. This results in synovial hyperplasia and osteoclastogenesis thus causing joint destruction and bony erosions.

AREAS COVERED

This review article summarizes trials that have studied the use of IL-17 targeted therapies in RA patients who have failed conventional synthetic disease-modifying therapy (C-DMARDS) and biologic DMARDS.

EXPERT OPINION

The trials that have studied IL-17 inhibitors in RA patients have only shown a modest improvement in disease activity. In several trials, the primary endpoint was not achieved whilst in others, when comparing with existing licensed biologics for RA, did not demonstrate any superiority.Tissue Necrosis Factor-alpha (TNF-α) likely plays more of a pivotal role in the pathogenesis of RA with IL-17 having a synergistic effect. Therefore, in our opinion, IL-17 inhibitors as an independent therapy for RA are less likely to provide a cost-effective benefit. There may be scope to potentially combine it with TNF-α-inhibitors (TNF-i), but this requires further research especially with the potential concerns related to increased immunosuppression.

Association of Interleukin-17 Inhibitors With Hypertension in Patients With Autoimmune Diseases: A Systematic Review and Meta-analysis on Randomized Controlled Trials

The influence of IL-17 inhibition on blood pressure in autoimmune disease patients remains inconclusive. Our objective is to examine the risk of hypertension in patients with autoimmune diseases undergoing IL-17 inhibition therapies via meta-analysis of randomized, placebo-controlled trials (RCTs). We obtained integrated data from PubMed, Embase, and ClinicalTrials.gov. Incident hypertension rates were calculated, and hazard ratios (HRs) with 95% confidence intervals (CIs) were analyzed, along with Ι^2 statistics to assess heterogeneity. Sequential analysis ensured conclusion reliability. In 30 RCTs involving 9,909 patients with diverse autoimmune diseases treated with anti-IL-17 agents, our meta-analysis revealed a significant increase in hypertension risk (RR 1.69, CI 1.24-2.31, p=0.001), robustly supported by trial sequential analysis. Among the four agents (secukinumab, ixekizumab, bimekizumab, and brodalumab), only secukinumab exhibited a notable association with hypertension. Patients with various primary autoimmune diseases, particularly those with psoriatic arthritis, had a higher likelihood of developing hypertension; in rheumatic arthritis patient cohorts, anti-IL-17 agents did not elevate hypertension risk. Prolonged treatment duration correlated with an increased hypertension risk. Stratifying by gender, studies with a female predominance demonstrated a higher risk ratio for hypertension compared to male-predominant studies. This highlights that anti-IL-17 treatment escalates hypertension risk, emphasizing the need for extra caution when managing autoimmune disease patients. (Registered by PROSPERO, CRD42016053112).

Inflammation and Bone Metabolism in Rheumatoid Arthritis: Molecular Mechanisms of Joint Destruction and Pharmacological Treatments

Rheumatoid arthritis (RA) is an inflammatory disease characterized by a variety of symptoms and pathologies often presenting with polyarthritis. The primary symptom in the initial stage is joint swelling due to synovitis. With disease progression, cartilage and bone are affected to cause joint deformities. Advanced osteoarticular destruction and deformation can cause irreversible physical disabilities. Physical disabilities not only deteriorate patients' quality of life but also have substantial medical economic effects on society. Therefore, prevention of the progression of osteoarticular destruction and deformation is an important task. Recent studies have progressively improved our understanding of the molecular mechanism by which synovitis caused by immune disorders results in activation of osteoclasts; activated osteoclasts in turn cause bone destruction and para-articular osteoporosis. In this paper, we review the mechanisms of bone metabolism under physiological and RA conditions, and we describe the effects of therapeutic intervention against RA on bone.

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.

Oral Candida Infection in Psoriatic Patients Treated with IL17A Inhibitors: Report of 3 Cases and a Comprehensive Review of the Literature

An intact and fully functional immune system plays a crucial role in the prevention of several infectious diseases. Interleukin (IL)17 is significantly involved in oral mucosa immunity against several antigens and microorganisms, including Candida albicans (CA). Herein, we present three cases of oral candidiasis (OC) related to the use of an IL17A inhibitor for psoriasis. Three psoriatic individuals presented for evaluation of widespread symptomatic oral lesions temporally correlated with the onset of IL17A inhibitors (secukinumab in two patients and brodalumab in one patient). Clinical examination revealed either partially removable white plaques in an erythematous background (case #1) or diffuse erythematous lesions (cases #2 and 3) involving several areas of the oral mucosa. Cytology smear, accompanied by histopathologic examination in case #1, confirmed the clinical impression of OC in all three cases. All patients received antifungal therapy with satisfactory clinical response. No discontinuation of the antipsoriatic regimen was recommended, but all patients were advised to remain under monitoring for possible OC relapses. During the last few years, new systemic biologic agents targeting IL17 have been used for the management of variable immune-mediated diseases. Few clinical trials and scarce case reports have shown that these medications place individuals at high risk of developing candidiasis. We propose that patients treated with these medications should be at close monitoring for the development of OC and, if it occurs, receive appropriate management.

Joint Statement (DZK, DGRh, DDG) on the Tuberculosis Risk with Treatment Using Novel Non-TNF-Alpha Biologicals

BACKGROUND

 While the risk of tuberculosis (TB) reactivation is adequately documented in relation to TNF-alpha inhibitors (TNFi), the question of what the tuberculosis risk is for newer, non-TNF biologics (non-TNFi) has not been thoroughly addressed.

METHODS

 We conducted a systematic review of randomized phase 2 and phase 3 studies, and long-term extensions of same, published through March 2019. Of interest was information pertaining to screening and treating of latent tuberculosis (LTBI) in association with the use of 12 particular non-TNFi. Only rituximab was excluded. We searched MEDLINE and the ClinicalTrial.gov database for any and all candidate studies meeting these criteria.

RESULTS

 677 citations were retrieved; 127 studies comprising a total of 34,293 patients who received non-TNFi were eligible for evaluation. Only 80 out of the 127 studies, or 63 %, captured active TB (or at least opportunistic diseases) as potential outcomes and 25 TB cases were reported. More than two thirds of publications (86/127, 68 %) mentioned LTBI screening prior to inclusion of study participants in the respective trial, whereas in only 4 studies LTBI screening was explicitly considered redundant. In 21 studies, patients with LTBI were generally excluded from the trials and in 42 out of the 127 trials, or 33 %, latently infected patients were reported to receive preventive therapy (PT) at least 3 weeks prior to non-TNFi treatment.

CONCLUSIONS

 The lack of information in many non-TNFi studies on the number of patients with LTBI who were either excluded prior to participating or had been offered PT hampers assessment of the actual TB risk when applying the novel biologics. Therefore, in case of insufficient information about drugs or drug classes, the existing recommendations of the German Central Committee against Tuberculosis should be applied in the same way as is done prior to administering TNFi. Well designed, long-term "real world" register studies on TB progression risk in relation to individual substances for IGRA-positive cases without prior or concomitant PT may help to reduce selection bias and to achieve valid conclusions in the future.

Rheumatoid Arthritis in the View of Osteoimmunology

Rheumatoid arthritis is characterized by synovial inflammation and irreversible bone erosions, both highlighting the immense reciprocal relationship between the immune and bone systems, designed osteoimmunology two decades ago. Osteoclast-mediated resorption at the interface between synovium and bone is responsible for the articular bone erosions. The main triggers of this local bone resorption are autoantibodies directed against citrullinated proteins, as well as pro-inflammatory cytokines and the receptor activator of nuclear factor-κB ligand, that regulate both the formation and activity of the osteoclast, as well as immune cell functions. In addition, local bone loss is due to the suppression of osteoblast-mediated bone formation and repair by inflammatory cytokines. Similarly, inflammation affects systemic bone remodeling in rheumatoid arthritis with the net increase in bone resorption, leading to systemic osteoporosis. This review summarizes the substantial progress that has been made in understanding the pathophysiology of systemic and local bone loss in rheumatoid arthritis.

Interleukin-17 in rheumatoid arthritis: Trials and tribulations

Interleukin-17A (IL-17A) is a pro-inflammatory cytokine with well-characterized biological effects on stromal cell activation, angiogenesis, and osteoclastogenesis. The presence of this cytokine in the inflamed joints of patients with rheumatoid arthritis (RA), together with compelling data from in vitro and experimental arthritis models demonstrating its pro-inflammatory effects, made this cytokine a strong candidate for therapeutic targeting. Clinical trials, however, have shown relatively modest success in RA as compared with other indications. Guided by recent insights in IL-17 biology, this review aims to explore possible reasons for the limited clinical efficacy of IL-17A blockade in RA, and what we can learn from these results going forward.

Risk for development of inflammatory bowel disease under inhibition of interleukin 17: A systematic review and meta-analysis

Objective

Cases of inflammatory bowel disease (IBD) during treatment with interleukin (IL)-17 antagonists have been reported from trials in psoriasis, psoriatic arthritis, and ankylosing spondylitis. The aim of this study was to assess the overall risk for development of IBD due to IL-17 inhibition.

Design

Systematic review and meta-analysis of studies conducted 2010–2018 of treatment with IL-17 antagonists in patients with psoriasis, psoriatic arthritis, ankylosing spondylitis, and rheumatoid arthritis. We compared risk of IBD development in anti-IL-17 treated patients compared to placebo treatments. We also computed incident rates of IBD overall. A ‘worst case scenario’ defining subjects ambiguous for prevalent versus incident cases for the latter was also applied.

Results

Sixty-six studies of 14,390 patients exposed to induction and 19,380 patients exposed to induction and/or maintenance treatment were included. During induction, 11 incident cases of IBD were reported, whereas 33 cases were diagnosed during the entire treatment period. There was no difference in the pooled risk of new-onset IBD during induction studies for both the best-case [risk difference (RD) 0.0001 (95% CI: -0.0011, 0.0013)] and worst-case scenario [RD 0.0008 (95% CI: -0.0005, 0.0022)]. The risk of IBD was not different from placebo when including data from maintenance and long-term extension studies [RD 0.0007 (95% CI: -0.0023, 0.0036) and RD 0.0022 (95% CI: -0.0010, 0.0055), respectively].

Conclusions

The risk for development of IBD in patients treated with IL-17 antagonists is not elevated. Prospective surveillance of patients treated with IL-17 antagonists with symptom and biomarker assessments is warranted to assess for onset of IBD in these patients.

[Biologicals and small molecules for rheumatoid arthritis]

In recent years tremendous progress has been made in the therapeutic management of rheumatoid arthritis. Rheumatologists now have a large armamentarium of highly efficient drugs with different mechanisms of action at their disposal. These new drugs consist of biologicals (biological disease-modifying antirheumatic drugs, bDMARDs) as well as targeted synthetic DMARDs (tsDMARD). A common feature of these new drugs for treatment of rheumatoid arthritis is that the molecular target of the drug is known, which is not the case for conventional DMARDs. With the help of the new drugs, the therapeutic goal of inducing remission in patients with rheumatoid arthritis has become reality for many patients. Nevertheless, there is still a significant proportion of patients who do not adequately respond to all available drugs, leaving room for still further improvement. This review gives a short overview on the currently available and effective substances for the treatment of rheumatoid arthritis.

Risk of Infections and Cancer in Patients With Rheumatologic Diseases Receiving Interleukin Inhibitors: A Systematic Review and Meta-analysis

IMPORTANCE

The safety profile of interleukin (IL) inhibitors is not well established.

OBJECTIVE

To assess the risk of serious infections, opportunistic infections, and cancer in patients with rheumatologic diseases treated with IL inhibitors.

DATA SOURCES

Ovid MEDLINE and Epub Ahead of Print, In-Process & Other Non-Indexed Citations; Ovid MEDLINE Daily; Ovid Embase; Ovid Cochrane Central Register of Controlled Trials; Ovid Cochrane Database of Systematic Reviews; and Scopus were searched (inception to November 30, 2018).

STUDY SELECTION

Randomized, placebo-controlled trials that evaluated IL inhibitor therapies in rheumatic diseases and reported safety data were included in the analyses.

DATA EXTRACTION AND SYNTHESIS

This systematic review is reported according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) statement. Two investigators independently extracted study data and assessed risk of bias and certainty in the evidence. Fixed-effects meta-analysis was conducted to pool odds ratios (ORs) for serious infections, opportunistic infections, and cancers for IL inhibitors vs placebo.

MAIN OUTCOMES AND MEASURES

The outcomes of interest were the number of serious infections, opportunistic infections, and cancers in individuals receiving IL inhibitor therapies compared with placebo.

RESULTS

In this meta-analysis, 74 studies comprising 29 214 patients (24 236 patients for serious infections, 9998 for opportunistic infections, and 21 065 for cancer [number of patients overlaps for each outcome]) were included. Patients receiving IL inhibitors had a higher risk of serious infections (OR, 1.97; 95% CI, 1.58-2.44; P < .001, I2 = 0%; high certainty), opportunistic infections (OR, 2.35; 95% CI, 1.09-5.05; P = .03, I2 = 0%; moderate certainty), and cancer (OR, 1.52; 95% CI, 1.05-2.19; P = .03, I2 = 11%; moderate certainty).

CONCLUSIONS AND RELEVANCE

The risk of serious infections, opportunistic infections, and cancer appears to be increased in patients with rheumatologic diseases who are treated with IL inhibitors compared with placebo.

Systematic review with meta-analysis: risk of new onset IBD with the use of anti-interleukin-17 agents

BACKGROUND

New onset IBD has been reported with the use of anti-IL-17 agents, but it remains unclear to what extent this is attributed to treatment or to underlying disease.

AIM

To evaluate the risk of new onset IBD with the use of anti-IL-17 agents METHODS: Electronic databases were searched for randomised controlled trials (RCT) of anti-IL-17 agents (brodalumab, ixekizumab and secukinumab). Risk of new onset IBD was compared to placebo by Mantel-Haenszel (MH) risk difference (RD). Sensitivity analyses including meta-analysis using fixed-effect model, MH and Peto odds ratio and MH risk ratio were performed due to incidence of rare adverse events. The risk of diarrhoea was also assessed due to the possibility of underdiagnosis of IBD.

RESULTS

Thirty-eight RCTs including 16 690 patients treated with anti-IL-17 agents were included. Twelve cases of new onset IBD were reported with anti-IL-17 agents in five studies, whereas no cases were reported with placebo. There was no difference in the risk of developing new onset IBD with anti-IL-17 agents compared to placebo (MH RD 0.00062, 95% CI -0.00072-0.0021, P = 0.35). Sensitivity analyses demonstrated no consistent risk with any method. There was no difference in the risk of diarrhoea (MH RD 0.0013, 95% CI -0.0014-0.0041, P = 0.34).

CONCLUSIONS

New onset IBD with the use of anti-IL-17 agents was rare. Interpretation of the results needs caution due to the presence of many zero-event studies.

Meta-analysis of IL-17 inhibitors in two populations of rheumatoid arthritis patients: biologic-naïve or tumor necrosis factor inhibitor inadequate responders

OBJECTIVES

To evaluate the efficacy and safety of interleukin 17 (IL-17) inhibitors in two rheumatoid arthritis (RA) populations: biologic-naïve or tumor necrosis factor inhibitor inadequate responders (TNF-IR).

METHOD

A systematic search was performed in major electronic databases to identify relevant randomized controlled trials (RCTs) reporting the American College of Rheumatology 20% (ACR20), ACR50, ACR70 responses and adverse events (AEs) of IL-17 inhibitors versus placebo in patients with RA. We divided these patients into two subgroups: biologic-naïve or TNF-IR. The meta-analysis was performed using Review Manager 5.3 software. Results were expressed as risk ratio (RR) with pertinent 95% confidence interval (95% CI).

RESULTS

Ten studies with a total of 2499 patients were included. For biologic-naïve patients, ACR50 and ACR70 responses were significantly better with IL-17 inhibitors than placebo (RR = 1.71, 95% CI 1.23-2.38, P = 0.001 and RR = 2.63, 95% CI 1.10-6.25, P = 0.03, respectively), but ACR20 responses for IL-17 inhibitors were not statistically superior to placebo (RR = 1.34, 95% CI 0.94-1.91, P = 0.11). For TNF-IR, IL-17 inhibitors were effective in achieving ACR20 (RR = 1.67, 95% CI 1.40-2.00, P < 0.00001), ACR50 (RR = 1.94, 95% CI 1.43-2.63, P < 0.0001), and ACR70 (RR = 2.11, 95% CI 1.26-3.55, P = 0.005) compared to placebo. In the safety analysis, IL-17 inhibitors did not show increased risk of any AEs by comparing to placebo in both biologic-naïve patients and TNF-IR.

CONCLUSION

IL-17 inhibitors were effective in the treatment of RA without increased risk of AEs, whether for biologic-naïve patients or TNF-IR. Key Points • In this meta-analysis comparing IL-17 inhibitors with placebo in 2499 rheumatoid arthritis patients, IL-17 inhibitors improved ACR50 and ACR70, but not ACR20, responses in biologic-naïve patients. • IL-17 inhibitors improved ACR20, ACR50, and ACR70 responses in tumor necrosis factor inhibitor inadequate responders.

Efficacy and safety of secukinumab in active rheumatoid arthritis with an inadequate response to tumor necrosis factor inhibitors: a meta-analysis of phase III randomized controlled trials

OBJECTIVES

To address the efficacy and safety of secukinumab in comparison with placebo in active rheumatoid arthritis (RA) patients who had an inadequate response to tumor necrosis factor (TNF) inhibitors.

METHODS

Databases of PubMed, Embase, and Web of Science were searched to identify the relevant randomized controlled trials (RCTs). Risk ratio (RR) and 95% confidence interval (95% CI) were calculated with the Mantel-Haenszel random effects method. Statistical heterogeneity was assessed using the Cochran Q and I² tests.

RESULTS

A total of 1292 patients from three phase III RCT studies were included. Compared with placebo, secukinumab 150 mg was superior at 24 weeks in terms of ACR20 with RR (1.66, 95% CI 1.33, 2.08; P < 0.0001; I² = 0%), ACR50 (1.88, 95% CI 1.29, 2.72; P = 0.0009; I² = 0%), and ACR70 (2.15, 95% CI 1.15, 4.02; P = 0.02; I² = 0%). Consistent effects were also observed in pooled group of 150 mg and 75 mg secukinumab. For secukinumab 75 mg alone, ACR20 response rate was significantly higher compared with placebo (RR 1.62, 95% CI 1.29, 2.03; P < 0.00001; I² = 0%). Although ACR50 and ACR70 response rates showed a favorable trend to be higher, no statistical difference was observed (RR 1.68, 95% CI 0.99, 2.85, P = 0.05, I² = 47%; RR 1.81, 95% CI 0.78, 4.21, P = 0.17, I² = 34%, respectively). Compared with the placebo group, there was no increased risk of adverse effects (AEs) and serious AEs at 16 weeks in the pooled secukinumab group.

CONCLUSIONS

In active RA patients with an inadequate response to TNF inhibitors, secukinumab may be a therapeutic option. Secukinumab 150 mg showed significantly better clinical efficacy with no increased risk of AEs and serious AEs compared with placebo.

TRIAL REGISTRATION

Clinical Trials.gov identifier: NCT01770379, NCT01350804, NCT01377012 Key Points • Secukinumab 150 mg showed significantly better clinical efficacy in active RA patients with an inadequate response to TNF inhibitors. • No increased risk of AEs and serious AEs in secukinumab group compared with placebo.

Osteoimmunology of Bone Loss in Inflammatory Rheumatic Diseases

Over the past two decades, the field of osteoimmunology has emerged in response to a range of evidence demonstrating the reciprocal relationship between the immune system and bone. In particular, localized bone loss, in the form of joint erosions and periarticular osteopenia, as well as systemic osteoporosis, caused by inflammatory rheumatic diseases including rheumatoid arthritis, the prototype of inflammatory arthritis has highlighted the importance of this interplay. Osteoclast-mediated resorption at the interface between synovium and bone is responsible for the joint erosion seen in patients suffering from inflammatory arthritis. Clinical studies have helped to validate the impact of several pathways on osteoclast formation and activity. Essentially, the expression of pro-inflammatory cytokines as well as Receptor Activator of Nuclear factor κB Ligand (RANKL) is, both directly and indirectly, increased by T cells, stimulating osteoclastogenesis and resorption through a crucial regulator of immunity, the Nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1). Furthermore, in rheumatoid arthritis, autoantibodies, which are accurate predictors both of the disease and associated structural damage, have been shown to stimulate the differentiation of osteoclasts, resulting in localized bone resorption. It is now also evident that osteoblast-mediated bone formation is impaired by inflammation both in joints and the skeleton in rheumatoid arthritis. This review summarizes the substantial progress that has been made in understanding the pathophysiology of bone loss in inflammatory rheumatic disease and highlights therapeutic targets potentially important for the cure or at least an alleviation of this destructive process.

Distinguishing rheumatoid arthritis from psoriatic arthritis

Rheumatoid arthritis (RA) and psoriatic arthritis (PsA) have key differences in clinical presentation, radiographic findings, comorbidities and pathogenesis to distinguish between these common forms of chronic inflammatory arthritis. Joint involvement is typically, but not always, asymmetric in PsA, while it is predominantly symmetric in RA. Bone erosions, without new bone growth, and cervical spine involvement are distinctive of RA, while axial spine involvement, psoriasis and nail dystrophy are distinctive of PsA. Patients with PsA typically have seronegative test findings for rheumatoid factor (RF) and cyclic citrullinated peptide (CCP) antibodies, while approximately 80% of patients with RA have positive findings for RF and CCP antibodies. Although there is overlap in the pathogenesis of PsA and RA, differences are also present that affect the efficacy of treatment. In PsA, levels of interleukin (IL)-1β, IL-6, IL-17, IL-22, IL-23, interferon-γ and tumour necrosis factor-α (TNF-α) are elevated, and in RA, levels of IL-1, IL-6, IL-22, IL-33, TNF-α, chemokine ligand 11 and chemokine C-X-C motif ligand 13 are elevated. Differences in the pathogenesis of RA and PsA translate into some variances in the specificity and efficacy of therapies.

Review: Transcriptional Regulation of CD4+ T Cell Differentiation in Experimentally Induced Arthritis and Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an autoimmune disorder characterized by chronic inflammation of the joint synovium and infiltration by activated inflammatory cells. CD4+ T cells form a large proportion of the inflammatory cells invading the synovial tissue, and are involved in the RA pathologic process. In general, CD4+ T cells differentiate into various T helper cell subsets and acquire the functional properties to respond to specific pathogens, and also mediate some autoimmune disorders such as RA. Because the differentiation of T helper cell subsets is determined by the expression of specific transcription factors in response to the cytokine environment, these transcription factors are considered to have a role in the pathology of RA. Treg cells control an excess of T cell–mediated immune response, and the transcription factor FoxP3 is critical for the differentiation and function of Treg cells. Treg cell dysfunction can result in the development of systemic autoimmunity. In this review, we summarize how the expression of transcription factors modulates T helper cell immune responses and the development of autoimmune diseases, especially in RA. Understanding the role of transcription factors in the pathogenesis of autoimmunity may lead to novel therapeutic strategies to control the differentiation and function of both T helper cells and Treg cells.

The role of IL-23 receptor signaling in inflammation-mediated erosive autoimmune arthritis and bone remodeling

The IL‐23/Th17 axis has been implicated in the development of autoimmune diseases, such as rheumatoid arthritis (RA) and psoriatic arthritis (PsA). RA and PsA are heterogeneous diseases with substantial burden on patients. Increasing evidence suggests that the IL‐23 signaling pathway may be involved in the development of autoimmunity and erosive joint damage. IL‐23 can act either directly or indirectly on bone forming osteoblasts as well as on bone resorbing osteoclasts. As IL‐23 regulates the activity of cells of the bone, it is conceivable that in addition to inflammation‐mediated joint erosion, IL‐23 may play a role in physiological bone remodeling. In this review, we focus on the role of IL‐23 in autoimmune arthritis in patients and murine models, and provide an overview of IL‐23 producing and responding cells in autoimmune arthritic joints. In addition, we discuss the role of IL‐23 on bone forming osteoblasts and bone resorbing osteoclasts regarding inflammation‐mediated joint damage and bone remodeling. At last, we briefly discuss the clinical implications of targeting this pathway for joint damage and systemic bone loss in autoimmune arthritis.

Secukinumab in Active Rheumatoid Arthritis after Anti-TNFα Therapy: A Randomized, Double-Blind Placebo-Controlled Phase 3 Study

Introduction

‘REASSURE’ (NCT01377012), a phase 3 study, evaluated the efficacy and safety of secukinumab in patients with active rheumatoid arthritis (RA) who had an inadequate response to, or intolerance of, tumor necrosis factor inhibitors (TNF-inhibitors).

Methods

A total of 637 patients were randomized (1:1:1) to receive intravenous secukinumab 10 mg/kg (baseline, weeks 2 and 4) followed by subcutaneous secukinumab 150 mg or 75 mg every 4 weeks (starting from week 8) or placebo at the same dosing schedule. The primary endpoint was the American College of Rheumatology 20% improvement criteria (ACR20) at week 24. Other predefined hierarchical endpoints included Health Assessment Questionnaire-Disability Index, van der Heijde modified total Sharp score (vdH-mTSS) at week 24, and major clinical response (MCR; continuous 6 month period of ACR70 response) at 1 year.

Results

The primary efficacy endpoint was met with both secukinumab dose groups: ACR20 response rate at week 24 was 35.2% for both secukinumab dose groups (P = 0.0009) vs 19.6% for placebo. The improvements in secondary endpoints were greater in the secukinumab dose groups vs placebo but did not meet statistical significance. The overall safety profile was similar across all treatment groups.

Conclusion

Secukinumab demonstrated efficacy in reducing disease activity over placebo as measured by ACR20 in patients with active RA who had an inadequate response to TNF-inhibitors. Secukinumab demonstrated a safety profile similar to other biologics currently approved for RA.

Funding

Novartis Pharma AG.

Trial registration

ClinicalTrials.gov identifier: NCT01377012.

Electronic supplementary material

The online version of this article (doi:10.1007/s40744-017-0086-y) contains supplementary material, which is available to authorized users.

Secukinumab and Sustained Improvement in Signs and Symptoms of Patients With Active Ankylosing Spondylitis Through Two Years: Results From a Phase III Study

Objective

Secukinumab improved the signs and symptoms of ankylosing spondylitis (AS) over 52 weeks in the phase III MEASURE 2 study. Here, we report longer‐term (104 weeks) efficacy and safety results.

Methods

Patients with active AS were randomized to subcutaneous secukinumab 150 mg, 75 mg, or placebo at baseline; weeks 1, 2, and 3; and every 4 weeks from week 4. The primary end point was the Assessment of SpondyloArthritis international Society criteria for 20% improvement (ASAS20) response rate at week 16. Other end points included ASAS40, high‐sensitivity C‐reactive protein, ASAS5/6, Bath Ankylosing Spondylitis Disease Activity Index, Short Form 36 health survey physical component summary, ASAS partial remission, EuroQol 5‐domain measure, and Functional Assessment of Chronic Illness Therapy fatigue subscale. End points were assessed through week 104, with multiple imputation for binary variables and a mixed‐effects model repeated measures for continuous variables.

Results

Of 219 randomized patients, 60 of 72 (83.3%) and 57 of 73 (78.1%) patients completed 104 weeks of treatment with secukinumab 150 mg and 75 mg, respectively; ASAS20/ASAS40 response rates at week 104 were 71.5% and 47.5% with both secukinumab doses, respectively. Clinical improvements with secukinumab were sustained through week 104 across all secondary end points. Across the entire treatment period (mean secukinumab exposure 735.6 days), exposure‐adjusted incidence rates for serious infections and infestations, Crohn's disease, malignant or unspecified tumors, and major adverse cardiac events with secukinumab were 1.2, 0.7, 0.5, and 0.7 per 100 patient‐years, respectively. No cases of tuberculosis reactivation, opportunistic infections, or suicidal ideation were reported.

Conclusion

Secukinumab provided sustained improvement through 2 years in the signs and symptoms of AS, with a safety profile consistent with previous reports.

Mechanistic rationales for targeting interleukin-17A in spondyloarthritis

The term spondyloarthritis (SpA) is used to describe a group of inflammatory autoimmune diseases, including ankylosing spondylitis and psoriatic arthritis, with common genetic risk factors and clinical features. SpA is clinically distinct from rheumatoid arthritis and typically affects the spine, sacroiliac joints, entheses, and, less commonly, peripheral joints. Although the pathogenesis of SpA is not fully understood, recent findings have identified the interleukin (IL)-17 pathway as a key mediator of disease pathogenesis. Clinical evidence for the efficacy of IL-17A inhibition by biologic agents was initially shown in patients with chronic plaque psoriasis, another autoimmune disease mediated by the IL-17 pathway. Subsequently, similar positive efficacy for inhibition of IL-17A was seen in patients with ankylosing spondylitis and psoriatic arthritis. Inhibition of IL-17A may also improve cardiovascular and metabolic comorbidities often found in patients with SpA because studies have linked these disorders to the IL-17 pathway. In this review, we will examine key preclinical studies that demonstrated the mechanistic role of IL-17A in the development SpA and discuss how these observations were translated into clinical practice.

MPO-ANCA-associated necrotizing glomerulonephritis in rheumatoid arthritis; a case report and review of literature

Background

Renal involvement in rheumatoid arthritis (RA) is common and has a negative impact on patient survival. Only few cases have been reported of necrotizing glomerulonephritis (GN) associated with myeloperoxidase anti-neutrophil cytoplasmic antibody (MPO-ANCA) in patients with RA.

Case Presentation

We report a patient with RA who developed a necrotizing GN associated with ANCA-MPO, treated with rituximab (RTX). A 55-year-old man with a 27-year history of RA under secukinumab was referred to our nephrology clinic with worsening renal function associated with microhematuria and proteinuria. Our laboratory evaluation showed hypocomplementemia and positive titers for MPO-ANCA (615 U/mL). A renal biopsy demonstrated pauci-immune necrotizing GN. The patient was treated with 3 consecutive pulses of methylprednisolone followed by oral prednisolone (1 mg/Kg) and rituximab (1000 mg, repeated 14 days later). After a 10-month follow-up, the arthritis remains well-controlled, renal function stabilized, proteinuria improved and MPO-ANCA titer normalized (6.3 U/mL).

Conclusions

Necrotizing GN is a rare but a serious condition and an early diagnosis is essential to treatment. This is the first case of necrotizing GN (without extra-renal manifestations of vasculitis) in a patient with active RA, successfully treated with RTX.

Functions of interleukin-34 and its emerging association with rheumatoid arthritis

Rheumatoid arthritis (RA) is a systemic autoimmune disease characterized by chronic, synovial inflammation affecting multiple joints, finally leading to extra-articular lesions for which limited effective treatment options are currently available. Interleukin-34 (IL-34), recently discovered as the second colony-stimulating factor-1 receptor (CSF-1R) ligand, is a newly discovered cytokine. Accumulating evidence has disclosed crucial roles of IL-34 in the proliferation and differentiation of mononuclear phagocyte lineage cells, osteoclastogenesis and inflammation. Recently, IL-34 was detected at high levels in patients with active RA and in experimental models of inflammatory arthritis. Blockade of functional IL-34 with a specific monoclonal antibody can reduce the severity of inflammatory arthritis, suggesting that targeting IL-34 or its receptors may constitute a novel therapeutic strategy for autoimmune diseases such as RA. Here, we have comprehensively discussed the structure and biological functions of IL-34, and reviewed recent advances in our understanding of the emerging role of IL-34 in the development of RA as well as its potential utility as a therapeutic target.