Effect of tocilizumab on neutrophils in adult patients with rheumatoid arthritis: pooled analysis of data from phase 3 and 4 clinical trials

Pharmacokinetics, pharmacodynamics and safety of oral formulation (CG-750) of ivaltinostat, a histone deacetylase inhibitor, compared to IV formulation (CG-745)

AIMS

CG-750 is an oral formulation of ivaltinostat, a newly developing histone deacetylase (HDAC) inhibitor. This study aimed to evaluate the pharmacokinetics (PK), pharmacodynamics (PD) and safety of an oral formulation (CG-750) of ivaltinostat compared to an intravenous (IV) formulation (CG-745).

METHODS

A randomized, double-blind, placebo-controlled study was conducted in three cohorts. Subjects received either CG-745 (Cohorts 1 and 3: 125 mg; Cohort 2: 250 mg) or placebo followed by CG-750 (Cohort 1: 125 mg; Cohort 2: 375 mg; Cohort 3: 750 mg) or placebo. Blood samples for PK and PD assessment were collected up to 72 h post-dose. Histone H3 acetylation at sites K9, K9/K14 and K27 was assessed for area under the % acetylation induction versus time curve (AUEC).

RESULTS

A total of 25 subjects were randomized, and 23 subjects completed the study (Cohort 1, n = 6; Cohort 2, n = 6; Cohort 3, n = 6; placebo, n = 5). The mean bioavailability of CG-750 was 10.6% (range: 4.18%-21.33%) and displayed linear PK in the dose range of 125-750 mg. The comparison of AUEC between formulations and the evaluation of the dose-AUEC relationship were inconclusive, due to the small sample sizes and significant variability observed in PD markers. All adverse events (AEs) were transient and of mild or moderate intensity.

CONCLUSIONS

The oral formulation of ivaltinostat (CG-750) was generally well tolerated after a single dose. CG-750 displayed a mean bioavailability of 10.6%.

Long-term Effects of IL-6 Receptor Blockade Therapy on Regulatory Lymphocytes and Neutrophils in Neuromyelitis Optica Spectrum Disorder

BACKGROUND AND OBJECTIVES

Neuromyelitis optica spectrum disorder (NMOSD) is a disabling autoimmune neurologic disease. Anti-IL-6 receptor (IL-6R) therapy prevents relapses in patients with anti-aquaporin 4 (AQP4)-IgG-positive NMOSD; however, it remains unclear how cellular immune components are altered by anti-IL-6R therapy. In this study, we examined the long-term effects of the anti-IL-6R monoclonal antibody tocilizumab (TCZ) on immune cell profiles in patients with NMOSD.

METHODS

Monthly IV injections of TCZ (8 mg/kg) were administered as an add-on therapy to 19 anti-AQP4-IgG-positive patients, who had been refractory to corticosteroids and immunosuppressive drugs. Peripheral blood was collected before infusion of TCZ for flow cytometry analysis of lymphocyte subsets. Seven patients provided whole blood samples for gene expression profiles.

RESULTS

Patients with NMOSD had reduced numbers of lymphocyte subsets with regulatory functions, including transitional B cells, CD56high NK cells, and CD45RA-FoxP3high regulatory T cells. However, after initiating TCZ therapy, the numbers increased to normal levels within 1 year. Gene expression analysis revealed that neutrophil granule-related genes, predominated by those related to azurophil granules, were significantly upregulated in patients with NMOSD. Such alterations suggestive of accelerated myeloid turnover were not observed 1 year after TCZ therapy, and the effects of TCZ on some neutrophil genes were observed as early as 5 days after starting TCZ. In vitro analysis demonstrated that naïve T-cell division was impaired in the enrolled patients, which was fully recovered after 18 months of therapy.

DISCUSSION

In patients with active NMOSD not treated with molecular targeting drugs, we observed reduction or deficiency in lymphocytes with regulatory potentials and activation of neutrophils. However, introduction of anti-IL-6R therapy accompanied by tapering concomitant drugs corrected such abnormalities, which might contribute to persistent relapse prevention. The recovery in the naïve T-cell division after starting TCZ may underlie the relatively low risk of infection in patients under anti-IL-6R therapy.

TRIAL REGISTRATION INFORMATION

University Hospital Medical Information Network Clinical Trials Registry: UMIN000005889 (July 8, 2011) and UMIN000007866 (May 1, 2012) (umin.ac.jp/ctr/index.htm). The first participant was enrolled on November 2, 2011.

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.

The prospects of interleukin-6 inhibition in rheumatoid arthritis: Olokizumab (novel monoclonal antibodies to IL-6)

Rheumatoid arthritis (RA) is a chronic immune-mediated rheumatic diseases (IMRDs) manifested with progressive destruction of joints, systemic inflammation of visceral organs and a wide range of co-morbidities associated with chronic inflammation. Among the cytokines involved in the pathogenesis of RA and certain other IMRDs, the role of interleukin (IL) 6 is of special interest. The introduction of mAbs tocilizumab (TCZ) and later sarilumab (SAR), both blocking the receptor of this cytokine, into clinical practice was an important achievement in the treatment of IIRDs at the beginning of the 21st century. As a novel approach in the treatment of RA, the humanized mAb against IL-6 olokizumab (OKZ) is in development by the Russian company R-PHARM under the license agreement with UCB Pharma. The review examines new data on efficacy and safety of OKZ in RA and the prospects of its use in rheumatology

Role of SARS-CoV-2-induced Cytokine Storm in Multi-Organ Failure: Molecular Pathways and Potential Therapeutic Options

Coronavirus disease 2019 (COVID-19) outbreak has become a global public health emergency and has led to devastating results. Mounting evidence proposes that the disease causes severe pulmonary involvement and influences different organs, leading to a critical situation named multi-organ failure. It is yet to be fully clarified how the disease becomes so deadly in some patients. However, it is proven that a condition called “cytokine storm” is involved in the deterioration of COVID-19. Although beneficial, sustained production of cytokines and overabundance of inflammatory mediators causing cytokine storm can lead to collateral vital organ damages. Furthermore, cytokine storm can cause post-COVID-19 syndrome (PCS), an important cause of morbidity after the acute phase of COVID-19. Herein, we aim to explain the possible pathophysiology mechanisms involved in COVID-19-related cytokine storm and its association with multi-organ failure and PCS. We also discuss the latest advances in finding the potential therapeutic targets to control cytokine storm wishing to answer unmet clinical demands for treatment of COVID-19.

Immune-related adverse events of biological immunotherapies used in COVID-19

The use of biological immunotherapeutic drugs is one of the options currently being evaluated and employed to manage COVID-19, specifically monoclonal antibodies, which have shown benefit by regulating the excessive immune response seen in patients with severe infection, known as a cytokine storm. Tocilizumab has received particular importance for this clinical application, as has sarilumab. Both drugs share a substantial similarity in terms of pharmacodynamics, being inhibitors of the interleukin six receptor (IL-6Rα). Furthermore, sotrovimab, a neutralizing anti-SARS CoV-2 antibody, has gained the attention of the scientific community since it has recently been authorized under certain circumstances, positioning itself as a new therapeutic alternative in development. However, despite their clinical benefit, biological immunotherapies have the potential to generate life-threatening immune-related adverse events. Therefore it is essential to review their incidence, mechanism, and risk factors. This review aims to provide a comprehensive understanding of the safety of the biological immunotherapeutic drugs currently recommended for the treatment of COVID-19, provide a review of the known immune-mediated adverse events and explore the potential immune-related mechanisms of other adverse reactions.

Bacterial and Viral Infection and Sepsis in Kidney Transplanted Patients

Kidney transplanted patients are a unique population with intrinsic susceptibility to viral and bacterial infections, mainly (but not exclusively) due to continuous immunosuppression. In this setting, infectious episodes remain among the most important causes of death, with different risks according to the degree of immunosuppression, time after transplantation, type of infection, and patient conditions. Prevention, early diagnosis, and appropriate therapy are the goals of infective management, taking into account that some specific characteristics of transplanted patients may cause a delay (the absence of fever or inflammatory symptoms, the negativity of serological tests commonly adopted for the general population, or the atypical anatomical presentation depending on the surgical site and graft implantation). This review considers the recent available findings of the most common viral and bacterial infection in kidney transplanted patients and explores risk factors and outcomes in septic evolution.

Dynamic Changes of the Neutrophil-to-Lymphocyte Ratio, Systemic Inflammation Index, and Derived Neutrophil-to-Lymphocyte Ratio Independently Predict Invasive Mechanical Ventilation Need and Death in Critically Ill COVID-19 Patients

BACKGROUND

Hematological indices can predict disease severity, progression, and death in patients with coronavirus disease-19 (COVID-19).

OBJECTIVES

To study the predictive value of the dynamic changes (first 48 h after ICU admission) of the following ratios: neutrophil-to-lymphocyte (NLR), platelet-to-lymphocyte (PLR), monocyte-to-lymphocyte (MLR), systemic inflammation index (SII), and derived neutrophil-to-lymphocyte (dNLR) for invasive mechanical ventilation (IMV) need and death in critically ill COVID-19 patients.

METHODS

Observational, retrospective, and multicentric analysis on 272 patients with severe or critical COVID-19 from two tertiary centers. Hematological indices were adjusted for confounders through multivariate analysis using Cox regression.

RESULTS

Patients comprised 186 males and 86 females with no difference across groups (p > 0.05). ΔNLR > 2 had the best independent predictive value for IMV need (HR = 5.05 (95% CI, 3.06-8.33, p < 0.0001)), followed by ΔSII > 340 (HR = 3.56, 95% CI 2.21-5.74, p < 0.0001) and ΔdNLR > 1 (HR = 2.61, 95% CI 1.7-4.01, p < 0.0001). Death was also best predicted by an NLR > 11 (HR = 2.25, 95% CI: 1.31-3.86, p = 0.003) followed by dNLR > 6.93 (HR = 1.89, 95% CI: 1.2-2.98, p = 0.005) and SII > 3700 (HR = 1.68, 95% CI: 1.13-2.49, p = 0.01).

CONCLUSIONS

Dynamic changes of NLR, SII, and dNLR independently predict IMV need and death in critically ill COVID-19 patients.

Neutrophil count reduction 1 month after initiating tocilizumab can predict clinical remission within 1 year in rheumatoid arthritis patients

Neutropenia is a common adverse event of tocilizumab (TCZ) in rheumatoid arthritis (RA) patients; however, the association between the decrease in neutrophil counts and the TCZ clinical efficacy remains inconclusive. This study aimed to examine whether TCZ-induced neutrophil decrease at 1 month predicts clinical remission within 1 year. We reviewed medical records of RA patients initiating TCZ between May 2011 and September 2019 in our hospital. The Clinical Disease Activity Index (CDAI) was evaluated at baseline (before initiating TCZ) and 1, 3, 6, and 12 months after administration. Clinical remission was defined when CDAI decreased ≤ 2.8. The ratio of neutrophil counts 1 month after initiating TCZ to those at baseline (neutrophil ratio) was also calculated. Among 255 TCZ-treated patients, 169 with valid CDAI and neutrophil counts were enrolled (with median age of 60 years and 79% females). Rheumatoid factor and anti-cyclic citrullinated peptide antibody were positive in 75% and 83%, respectively, and 56% of the patients had concomitant methotrexate (median dose: 8 mg/week). Multivariate logistic regression analysis suggested baseline CDAI (odds ratio (OR) 0.96, p = 0.045), concomitant PSL (OR 0.42, p = 0.030), and the neutrophil ratio (OR 0.19, p = 0.011) as predictors of CDAI remission. Neutrophil ratio ≤ 0.8 was associated with achieving remission (Fisher's exact test, p = 0.02) with no apparent increase of severe infection. More than 20% reduction of neutrophil count 1 month after initiating TCZ predicts clinical remission within 1 year at an early treatment phase.

Severe prolonged neutropenia following administration of tocilizumab in a patient affected by COVID-19: a case report and brief review of the literature

Tocilizumab is one of the newest therapeutic options for the acute respiratory distress syndrome (ARDS) caused by the recently discovered severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) β-coronavirus. Several trials are currently ongoing to assess the efficacy and safety profile of tocilizumab in treating ARDS. In this article, we present the case of a Black patient with acute pneumonia who benefited greatly from tocilizumab, but developed severe prolonged neutropenia. Considering the increasing use of tocilizumab among patients with coronavirus disease 2019 (COVID-19), this case warrants further research regarding the possible adverse hematological effects that need to be monitored in order to prevent secondary infections.

Understanding the Role of Interleukin-6 (IL-6) in the Joint and Beyond: A Comprehensive Review of IL-6 Inhibition for the Management of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is a chronic, debilitating autoimmune disorder involving inflammation and progressive destruction of the joints, affecting up to 1% of the population. The majority of patients with RA have one or more comorbid conditions, the most common being cardiovascular disease, osteoporosis, and depression, the presence of which are associated with poorer clinical outcomes and lower health-related quality of life. RA pathogenesis is driven by a complex network of proinflammatory cells and cytokines, and of these, interleukin-6 (IL-6) plays a key role in the chronic inflammation associated with RA. Through cell signaling that can be initiated by both membrane-bound and soluble forms of its receptor, IL-6 acts both locally to promote joint inflammation and destruction, and in the circulation to mediate extra-articular manifestations of RA, including pain, fatigue, morning stiffness, anemia, and weight loss. This narrative review describes the role of IL-6 in the pathogenesis of RA, its comorbidities, and extra-articular systemic manifestations, and examines the effects of the IL-6 receptor inhibitors sarilumab and tocilizumab on clinical endpoints of RA, patient-reported outcomes, and common comorbidities and extra-articular manifestations.

Immune responses during COVID-19 infection

Over the past 16 years, three coronaviruses (CoVs), severe acute respiratory syndrome CoV (SARS-CoV) in 2002, Middle East respiratory syndrome CoV (MERS-CoV) in 2012 and 2015, and SARS-CoV-2 in 2020, have been causing severe and fatal human epidemics. The unpredictability of coronavirus disease-19 (COVID-19) poses a major burden on health care and economic systems across the world. This is caused by the paucity of in-depth knowledge of the risk factors for severe COVID-19, insufficient diagnostic tools for the detection of SARS-CoV-2, as well as the absence of specific and effective drug treatments. While protective humoral and cellular immune responses are usually mounted against these betacoronaviruses, immune responses to SARS-CoV2 sometimes derail towards inflammatory tissue damage, leading to rapid admissions to intensive care units. The lack of knowledge on mechanisms that tilt the balance between these two opposite outcomes poses major threats to many ongoing clinical trials dealing with immunostimulatory or immunoregulatory therapeutics. This review will discuss innate and cognate immune responses underlying protective or deleterious immune reactions against these pathogenic coronaviruses.

Subcutaneous tocilizumab treatment in patients with severe COVID-19-related cytokine release syndrome: An observational cohort study

BACKGROUND

Patients with severe coronavirus disease 2019 (COVID-19) have elevated levels of acute phase reactants and inflammatory cytokines, including interleukin-6, indicative of cytokine release syndrome (CRS). The interleukin-6 receptor inhibitor tocilizumab is used for the treatment of chimeric antigen receptor T-cell therapy-induced CRS.

METHODS

Patients aged 18 years or older with laboratory-confirmed COVID-19 admitted to the Annunziata Hospital in Cosenza, Italy, through March 7, 2020, who received at least one dose of tocilizumab 162 mg subcutaneously for the treatment of COVID-19-related CRS in addition to standard care were included in this retrospective observational study. The primary observation was the incidence of grade 4 CRS after tocilizumab treatment. Chest computed tomography (CT) scans were evaluated to investigate lung manifestations.

FINDINGS

Twelve patients were included; all had fever, cough, and fatigue at presentation, and all had at least one comorbidity (hypertension, six patients; diabetes, five patients; chronic obstructive lung disease, four patients). Seven patients received high-flow nasal cannula oxygen therapy and five received non-invasive mechanical ventilation for lung complications of COVID-19. No incidence of grade 4 CRS was observed within 1 week of tocilizumab administration in all 12 patients (100%) and within 2 days of tocilizumab administration in 5 patients (42%). The predominant pattern on chest CT scans at presentation was ground-glass opacity, air bronchograms, smooth or irregular interlobular or septal thickening, and thickening of the adjacent pleura. Follow-up CT scans 7 to 10 days after tocilizumab treatment showed improvement of lung manifestations in all patients. No adverse events or new safety concerns attributable to tocilizumab were reported.

INTERPRETATION

Tocilizumab administered subcutaneously to patients with COVID-19 and CRS is a promising treatment for reduction in disease activity and improvement in lung function. The effect of tocilizumab should be confirmed in a randomised controlled trial.

Population Pharmacodynamic Model of Neutrophil Margination and Tolerance to Describe Effect of Sarilumab on Absolute Neutrophil Count in Patients with Rheumatoid Arthritis

Evidence suggests that effects of interleukin‐6 pathway inhibitors sarilumab, tocilizumab, and sirukumab on absolute neutrophil count (ANC) are due to margination of circulating neutrophils into rapidly mobilizable noncirculating pools. We developed a population pharmacodynamic model using compartments for neutrophil margination and ANC‐specific tolerance to describe rapid, transient ANC changes in blood following administration of subcutaneous sarilumab and intravenous/subcutaneous tocilizumab based on data from 322 patients with rheumatoid arthritis in two single‐dose (NCT02097524 and NCT02404558) and one multiple‐dose (NCT01768572) trials. The model incorporated a tolerance compartment to account for ANC nadir and beginning of recovery before maximal drug concentration after subcutaneous dosing, and absence of a nadir plateau when the ANC response is saturated after subcutaneous or intravenous dosing. The model effectively describes the ANC changes and supports neutrophil margination and tolerance as an explanation for the absence of increased infection risk associated with low ANC due to interleukin‐6 pathway inhibitor treatment.

Exacerbation of Chikungunya Virus Rheumatic Immunopathology by a High Fiber Diet and Butyrate

Chikungunya virus (CHIKV) is a mosquito transmitted alphavirus associated with a robust systemic infection and an acute inflammatory rheumatic disease. A high fiber diet has been widely promoted for its ability to ameliorate inflammatory diseases. Fiber is fermented in the gut into short chain fatty acids such as acetate, propionate, and butyrate, which enter the circulation providing systemic anti-inflammatory activities. Herein we show that mice fed a high fiber diet show a clear exacerbation of CHIKV arthropathy, with increased edema and neutrophil infiltrates. RNA-Seq analyses illustrated that a high fiber diet, in this setting, promoted a range of pro-neutrophil responses including Th17/IL-17. Gene Set Enrichment Analyses demonstrated significant similarities with mouse models of inflammatory psoriasis and significant depression of macrophage resolution phase signatures in the CHIKV arthritic lesions from mice fed a high fiber diet. Supplementation of the drinking water with butyrate also increased edema after CHIKV infection. However, the mechanisms involved were different, with modulation of AP-1 and NF-κB responses identified, potentially implicating deoptimization of endothelial barrier repair. Thus, neither fiber nor short chain fatty acids provided benefits in this acute infectious disease setting, which is characterized by widespread viral cytopathic effects and a need for tissue repair.

Gaps in Ambulatory Patient Safety for Immunosuppressive Specialty Medications

OBJECTIVES

New specialty drugs such as biologics are now available in record numbers, presenting increased safety risks for people with immune-mediated diseases. However, comprehensive assessments of patient safety for these drugs are lacking. We examined performance on key patient safety measures, such as screening for latent tuberculosis (LTBI), hepatitis B virus (HBV), and hepatitis C virus (HCV), for new users of a broad group of specialty medications.

METHODS

Data were extracted via electronic health record data warehouses of a large university health system using structured queries, and extensive chart review was performed to confirm measure elements. We included all new users of immunosuppressive specialty drugs between 2013 and 2017. We assessed screening for LTBI, HBV, and HCV from 12 months before through 60 days after medication initiation, and calculated performance on a composite measure that required screening for all three infections. Multivariable logistic regression was used to assess differences in screening across specialties, adjusting for patient race, sex, age, and comorbidities.

RESULTS

Among 2027 patients, the most common drugs prescribed were adalimumab (32%), etanercept (24%), infliximab (19%), and ustekinumab (9%). Overall, 62% of patients were screened for LTBI, 42% for HBV, and 33% for HCV. Only 26% of patients were screened appropriately for all three infections. Screening patterns differed significantly according to treating specialty.

CONCLUSIONS

We found gaps in ambulatory safety for patients treated with immunosuppressive specialty drugs for diverse inflammatory conditions across all relevant treating specialties. More robust safety protocols are urgently needed to prevent serious patient safety events in this high-risk population.

Efficacy and safety profile of intravenous tocilizumab versus intravenous abatacept in treating female Saudi Arabian patients with active moderate-to-severe rheumatoid arthritis

OBJECTIVES

To compare the efficacy and safety of tocilizumab with those of abatacept in patients with active rheumatoid arthritis not responding to anti-tumor necrosis factor therapy.

METHODS

A prospective, open-label study was carried out on adult females with moderate-to-severe rheumatoid arthritis. Patients were randomly assigned to receive either intravenous tocilizumab or abatacept treatment. History taking, clinical examination, and laboratory evaluation were done at baseline and during a 24-week period of follow-up. Disease activity was calculated using the DAS28-ESR score. The incidence of accompanying adverse events was evaluated and all statistical analyses were performed by InStat.

RESULTS

One hundred thirty-two patients were enrolled and classified randomly into the tocilizumab (n = 68) and abatacept (n = 64) groups. By week 24, the mean DAS28-ESR was significantly reduced in both groups (P < 0.0001) in association with significant reductions in CRP, ESR, and HAQ scores. No significant difference in the incidence rate of adverse effects appeared between both study groups. However, there were marked declines in the hemoglobin levels (P = 0.003) and neutrophil count (P = 0.002) together with significant elevations in systolic blood pressure (P = 0.002), liver enzymes (P = 0.001), total cholesterol (P = 0.001), and high-density lipoproteins (P = 0.002) in the tocilizumab group compared with the abatacept group.

CONCLUSION

Both intravenous abatacept and tocilizumab significantly decreased the disease activity and improved the physical function in rheumatoid arthritis patients who failed to respond to anti-tumor necrosis factor therapy. Although the efficacy of both drugs was similar, abatacept showed a more promising short-term safety profile since it was associated with less adverse effects and better laboratory outcomes.

Neutrophil Function in an Inflammatory Milieu of Rheumatoid Arthritis

Rheumatoid arthritis (RA) is an inflammatory autoimmune disease characterized by the presence of autoantibodies against citrullinated protein antigens and proinflammatory cytokines which cause chronic synovitis, bone erosion, and eventual deformity; however, the precise etiology of RA is unclear. In the early stage of RA, neutrophils migrate into the articular cavity, become activated, and exert their function in an inflammatory process, suggesting an essential role of neutrophils in the initial events contributing to the pathogenesis of RA. Solid evidence exists that supports the contribution of neutrophil extracellular traps (NETs) to the production of autoantibodies against citrullinated proteins which can trigger the immune reaction in RA. Concurrently, proinflammatory cytokines regulate the neutrophil migration, apoptosis, and NET formation. As a result, the inflammatory neutrophils produce more cytokines and influence other immune cells thereby perpetuating the inflammatory condition in RA. In this review, we summarize the advances made in improving our understanding of neutrophil migration, apoptosis, and NET formation in the presence of an RA inflammatory milieu. We will also discuss the most recent strategies in modulating the inflammatory microenvironment that have an impact on neutrophil function which may provide alternative novel therapies for RA.

Failure of tocilizumab in treating two patients with refractory SAPHO syndrome: a case report

Synovitis, acne, pustulosis, hyperostosis, and osteitis (SAPHO) syndrome is a rare autoinflammatory disease with no standard treatment. Interleukin (IL)-6 inhibitors represent a novel therapeutic option for rheumatoid arthritis and some autoinflammatory diseases. However, the clinical utility of IL-6 inhibitors in treating SAPHO syndrome has been poorly investigated. In the present report, we describe two patients with SAPHO syndrome that was unresponsive to conventional treatment. Tocilizumab, an anti-IL-6 receptor monoclonal antibody, was putatively administered according to positive IL-6 immunohistochemical staining in biopsied bone tissues. However, the disease continued to progress, and new-onset or worsening skin lesions were noted with transient neutropenia. These cases demonstrate that tocilizumab may not be an ideal option for treating SAPHO syndrome.

The Two-Faced Cytokine IL-6 in Host Defense and Diseases

Interleukein-6 (IL-6), is produced locally from infectious or injured lesions and is delivered to the whole body via the blood stream, promptly activating the host defense system to perform diverse functions. However, excessive or sustained production of IL-6 is involved in various diseases. In diseases, the IL-6 inhibitory strategy begins with the development of the anti-IL-6 receptor antibody, tocilizumab (TCZ). This antibody has shown remarkable effects on Castleman disease, rheumatoid arthritis and juvenile idiopathic arthritis. In 2017, TCZ was proven to work effectively against giant cell arteritis, Takayasu arteritis and cytokine releasing syndrome, initiating a new era for the treatment of these diseases. In this study, the defensive functions of IL-6 and various pathological conditions are compared. Further, the diseases of which TCZ has been approved for treatment are summarized, the updated results of increasing off-label use of TCZ for various diseases are reviewed and the conditions for which IL-6 inhibition might have a beneficial role are discussed. Given the involvement of IL-6 in many pathologies, the diseases that can be improved by IL-6 inhibition will expand. However, the important role of IL-6 in host defense should always be kept in mind in clinical practice.

New insights and long-term safety of tocilizumab in rheumatoid arthritis

Rheumatoid arthritis is a leading musculoskeletal cause of disability in Western society. Therapeutic options have expanded rapidly with the advent of biological agents as treatment options. One of these, tocilizumab, targets the interleukin-6 receptor and has been approved since the late 2000s in many jurisdictions. This approval was based on 6-12 month trials. It is now appropriate to look at longer-term studies and what new insights they have provided into this agent. Data are based largely on observational studies with their well-known limitations as well as some further randomized trials and provide a number of important observations regarding both efficacy and safety. In conclusion, the longer-term data suggest tocilizumab efficacy increases over time for both signs and symptoms and radiographic change. It is also corticosteroid sparing. The safety data are consistent with the shorter-term trials and are largely reassuring but some questions still remain over cardiovascular safety and cancer risk.

New insights and long-term safety of tocilizumab in rheumatoid arthritis

Rheumatoid arthritis is a leading musculoskeletal cause of disability in Western society. Therapeutic options have expanded rapidly with the advent of biological agents as treatment options. One of these, tocilizumab, targets the interleukin-6 receptor and has been approved since the late 2000s in many jurisdictions. This approval was based on 6-12 month trials. It is now appropriate to look at longer-term studies and what new insights they have provided into this agent. Data are based largely on observational studies with their well-known limitations as well as some further randomized trials and provide a number of important observations regarding both efficacy and safety. In conclusion, the longer-term data suggest tocilizumab efficacy increases over time for both signs and symptoms and radiographic change. It is also corticosteroid sparing. The safety data are consistent with the shorter-term trials and are largely reassuring but some questions still remain over cardiovascular safety and cancer risk.

Two years of sarilumab in patients with rheumatoid arthritis and an inadequate response to MTX: safety, efficacy and radiographic outcomes

Objectives

To examine 2-year safety, efficacy and radiographic outcomes of sarilumab in adults with RA and inadequate response to MTX (MTX-IR).

Methods

In the randomized, placebo-controlled MOBILITY trial, MTX-IR patients received subcutaneous sarilumab (150 or 200 mg) or placebo every 2 weeks (q2w) plus MTX for up to 1 year. Upon study completion, patients could enrol in the open-label, long-term extension study (EXTEND, NCT011046652), in which all patients received sarilumab 200 mg q2w plus MTX. Dose reduction to 150 mg q2w was allowed for abnormal laboratory findings and per investigator’s discretion.

Results

Of 1197 patients participating in MOBILITY, 901 entered EXTEND. Over the 2-year period, treatment-emergent adverse events (TEAEs) and serious AEs occurred at rates of 279.6 events per 100 patient-years and 16.6 events per 100 patient-years, respectively. The most common TEAEs were neutropenia, injection site erythema, increased alanine aminotransferase and upper respiratory tract infections. After 1 year in the open-label, long-term extension, disease activity reached similar levels regardless of initial treatment. Modified total Sharp scores at year 1 were maintained through year 2. Best radiographic outcomes were observed in patients initially randomized to sarilumab 200 mg q2w. After dose reduction, 89.4% of patients continued the study through 2 years.

Conclusion

Sarilumab safety through year 2 was consistent with IL-6 receptor blockade. Clinical response was similar irrespective of initial treatment, and radiographic progression stabilized. Patients initiated on sarilumab 200 mg q2w had the best radiographic outcomes. Dose reduction allowed most patients to continue with the study.

Interleukin-6: designing specific therapeutics for a complex cytokine

Interleukin-6 (IL-6) is a pivotal cytokine with a diverse repertoire of physiological functions that include regulation of immune cell proliferation and differentiation. Dysregulation of IL-6 signalling is associated with inflammatory and lymphoproliferative disorders such as rheumatoid arthritis and Castleman disease, and several classes of therapeutics have been developed that target components of the IL-6 signalling pathway. So far, monoclonal antibodies against IL-6 or IL-6 receptor (IL-6R) and Janus kinases (JAK) inhibitors have been successfully developed for the treatment of autoimmune diseases such as rheumatoid arthritis. However, clinical trials of agents targeting IL-6 signalling have also raised questions about the diseases and patient populations for which such agents have an appropriate benefit-risk profile. Knowledge from clinical trials and advances in our understanding of the complexities of IL-6 signalling, including the potential to target an IL-6 trans-signalling pathway, are now indicating novel opportunities for therapeutic intervention. In this Review, we overview the roles of IL-6 in health and disease and analyse progress with several approaches of inhibiting IL-6-signalling, with the aim of illuminating when and how to apply IL-6 blockade.

Rheumatoid arthritis: pathological mechanisms and modern pharmacologic therapies

Rheumatoid arthritis (RA) is a chronic systemic autoimmune disease that primarily affects the lining of the synovial joints and is associated with progressive disability, premature death, and socioeconomic burdens. A better understanding of how the pathological mechanisms drive the deterioration of RA progress in individuals is urgently required in order to develop therapies that will effectively treat patients at each stage of the disease progress. Here we dissect the etiology and pathology at specific stages: (i) triggering, (ii) maturation, (iii) targeting, and (iv) fulminant stage, concomitant with hyperplastic synovium, cartilage damage, bone erosion, and systemic consequences. Modern pharmacologic therapies (including conventional, biological, and novel potential small molecule disease-modifying anti-rheumatic drugs) remain the mainstay of RA treatment and there has been significant progress toward achieving disease remission without joint deformity. Despite this, a significant proportion of RA patients do not effectively respond to the current therapies and thus new drugs are urgently required. This review discusses recent advances of our  understanding of RA pathogenesis, disease modifying drugs, and provides perspectives on next generation therapeutics for RA.

The preclinical stages of rheumatoid arthritis (RA) represent a golden window for the development of therapies which could someday prevent the onset of clinical disease. The autoimmune processes underpinning RA usually begin many years before symptoms such as joint pain and stiffness emerge. Recent studies have identified some of the key cellular players driving these processes and begun to unpick how genetic and environmental risk factors combine to trigger them; they also suggest the existence of several distinct subtypes of RA, which require further exploration. Jiake Xu at the University of Western Australia in Perth and colleagues review current treatment strategies for RA and how such insights could ultimately lead to the earlier diagnosis of RA - as well as providing new opportunities for drug treatment and prevention through behavioral changes in high-risk individuals.

Tocilizumab in the treatment of adult rheumatoid arthritis

Rheumatoid arthritis (RA) is the most prevalent immune-mediated chronic rheumatic disease and is associated with joint destruction and disability. Therapeutic strategies, including biological disease-modifying antirheumatic drugs (bDMARDs) have improved the prognosis and quality of life of RA patients. Tocilizumab (TCZ) is a humanized monoclonal antibody against IL-6 receptor licensed in 2009 that has demonstrated clinical efficacy in various adult RA populations. RA management guidelines and recommendations consider TCZ as one of the bDMARDS indicated after methotrexate or other conventional synthetic DMARDs and/or TNF inhibitors failure in adult RA. Of particular interest is the demonstration of its effectiveness in monotherapy in comparison with other bDMARDs. Recent observational studies have shown good results for the safety profile of TCZ with no new alert signals.

Tocilizumab: A Review in Rheumatoid Arthritis

Intravenous (IV) and subcutaneous (SC) tocilizumab (RoActemra®), an IL-6 receptor antagonist, are approved (± methotrexate) in numerous countries throughout the world, for the treatment of adults with moderate to severe active rheumatoid arthritis (RA). Extensive clinical experience has firmly established the short- and long-term efficacy and safety of tocilizumab [monotherapy or in combination with conventional synthetic DMARDs (csDMARDs)] in adults with early-stage and longer-duration established RA. In the clinical trial and real-world settings, tocilizumab monotherapy or combination therapy provided rapid and sustained improvements in clinical and radiographic outcomes and health-related quality of life. The safety profile of tocilizumab is consistent over time and, in general, is consistent with that of other immunomodulatory agents. This narrative review, written from an EU perspective, summarizes the clinical use of IV and SC tocilizumab in RA. Given its low risk of immunogenicity, the flexibility of IV and SC administration and the convenience of the once-weekly, self-administered, SC regimen, tocilizumab provides an effective treatment for severe, active and progressive RA in adults not previously treated with methotrexate and an effective biologic first- or subsequent-line treatment for moderate to severe active RA in adults who have either responded inadequately to or were intolerant of previous therapy with ≥ 1 csDMARD or TNF inhibitor.