The fibroid phenotype of biological naïve patients with rheumatoid arthritis are less likely to respond to anti-IL-6R treatment.

Type III collagen gene expression is upregulated in the synovium of patients with rheumatoid arthritis (RA) presenting the fibroid phenotype. The soluble type III collagen formation biomarker, PRO-C3, is known to measure fibrogenesis in fibrotic diseases. In this exploratory study, we aimed to investigate the association between fibrogenesis (PRO-C3) and the disease- and treatment response in patients with RA. We measured PRO-C3 in subsets of two clinical trials assessing the effect of the anti-interleukin-6 (IL-6) receptor treatment tocilizumab (TCZ) as monotherapy or polytherapy with methotrexate. PRO-C3 levels had weak or very weak correlations with the clinical parameters (Spearman's). However, when the patients were divided into Disease Activity Score-28 groups characterized by the erythrocyte sedimentation rate (DAS28-ESR), there was a statistical difference between the PRO-C3 levels of the different groups (p < 0.05). To determine the response in relation to PRO-C3, a cut-off based on PRO-C3 levels and patients in remission (DAS28-ESR ≤ 2.6) was identified. This showed that a reduction in PRO-C3 after treatment initiation was associated with decreased DAS28-ESR and a higher response rate in patients with low PRO-C3 levels than in those with high PRO-C3 levels. This indicates that a fibrotic component affects the responsiveness of patients.

Targeting IL-6 or IL-6 Receptor in Rheumatoid Arthritis: What Have We Learned?

The use of different pathways in the treatment of rheumatoid arthritis has led to a significant decrease in the number of treatment-resistant patients. In this context, interleukin (IL)-6 inhibition has filled an important gap in rheumatoid arthritis treatment with its effectiveness and safety in both monotherapy and combinations. The process of IL-6 inhibition initiated with IL-6 receptor blockers has prompted questions regarding the potential impact and safety of different inhibitions of this pathway, such as the direct blockade of IL-6. Following the termination of the development of sirukumab because of mortality data in early studies, the investigation of olokizumab, which targets a different region of the IL-6 cytokine, has renewed the hope in this area and the safety concerns have been largely alleviated by the open-label extension data. In addition, the efficacy and safety of tocilizumab and sarilumab have led to a rapid investigation of biosimilars and new potent IL-6 receptor blockers. A comprehensive understanding of mechanisms of this pathway with further long-term clinical data and basic research may provide a decisive impact on selecting the appropriate mechanism as the first choice in personalized treatments.

Blockade of IL-6R prevents preterm birth and adverse neonatal outcomes.

BACKGROUND: Preterm birth preceded by spontaneous preterm labour often occurs in the clinical setting of sterile intra-amniotic inflammation (SIAI), a condition that currently lacks treatment. METHODS: Proteomic and scRNA-seq human data were analysed to evaluate the role of IL-6 and IL-1α in SIAI. A C57BL/6 murine model of SIAI-induced preterm birth was developed by the ultrasound-guided intra-amniotic injection of IL-1α. The blockade of IL-6R by using an aIL-6R was tested as prenatal treatment for preterm birth and adverse neonatal outcomes. QUEST-MRI evaluated brain oxidative stress in utero. Targeted transcriptomic profiling assessed maternal, foetal, and neonatal inflammation. Neonatal biometrics and neurodevelopment were tested. The neonatal gut immune-microbiome was evaluated using metagenomic sequencing and immunophenotyping. FINDINGS: IL-6 plays a critical role in the human intra-amniotic inflammatory response, which is associated with elevated concentrations of the alarmin IL-1α. Intra-amniotic injection of IL-1α resembles SIAI, inducing preterm birth (7% vs. 50%, p = 0.03, Fisher's exact test) and neonatal mortality (18% vs. 56%, p = 0.02, Mann-Whitney U-test). QUEST-MRI revealed no foetal brain oxidative stress upon in utero IL-1α exposure (p > 0.05, mixed linear model). Prenatal treatment with aIL-6R abrogated IL-1α-induced preterm birth (50% vs. 7%, p = 0.03, Fisher's exact test) by dampening inflammatory processes associated with the common pathway of labour. Importantly, aIL-6R reduces neonatal mortality (56% vs. 22%, p = 0.03, Mann-Whitney U-test) by crossing from the mother to the amniotic cavity, dampening foetal organ inflammation and improving growth. Beneficial effects of prenatal IL-6R blockade carried over to neonatal life, improving survival, growth, neurodevelopment, and gut immune homeostasis. INTERPRETATION: IL-6R blockade can serve as a strategy to treat SIAI, preventing preterm birth and adverse neonatal outcomes. FUNDING: NICHD/NIH/DHHS, Contract HHSN275201300006C. WSU Perinatal Initiative in Maternal, Perinatal and Child Health.

Selective immune suppression using interleukin-6 receptor inhibitors for management of immune-related adverse events.

BACKGROUND: Management of immune-related adverse events (irAEs) is important as they cause treatment interruption or discontinuation, more often seen with combination immune checkpoint inhibitor (ICI) therapy. Here, we retrospectively evaluated the safety and effectiveness of anti-interleukin-6 receptor (anti-IL-6R) as therapy for irAEs. METHODS: We performed a retrospective multicenter study evaluating patients diagnosed with de novo irAEs or flare of pre-existing autoimmune disease following ICI and were treated with anti-IL-6R. Our objectives were to assess the improvement of irAEs as well as the overall tumor response rate (ORR) before and after anti-IL-6R treatment. RESULTS: We identified a total of 92 patients who received therapeutic anti-IL-6R antibodies (tocilizumab or sarilumab). Median age was 61 years, 63% were men, 69% received anti-programmed cell death protein-1 (PD-1) antibodies alone, and 26% patients were treated with the combination of anti-cytotoxic T lymphocyte antigen-4 and anti-PD-1 antibodies. Cancer types were primarily melanoma (46%), genitourinary cancer (35%), and lung cancer (8%). Indications for using anti-IL-6R antibodies included inflammatory arthritis (73%), hepatitis/cholangitis (7%), myositis/myocarditis/myasthenia gravis (5%), polymyalgia rheumatica (4%), and one patient each with autoimmune scleroderma, nephritis, colitis, pneumonitis and central nervous system vasculitis. Notably, 88% of patients had received corticosteroids, and 36% received other disease-modifying antirheumatic drugs (DMARDs) as first-line therapies, but without adequate improvement. After initiation of anti-IL-6R (as first-line or post-corticosteroids and DMARDs), 73% of patients showed resolution or change to ≤grade 1 of irAEs after a median of 2.0 months from initiation of anti-IL-6R therapy. Six patients (7%) stopped anti-IL-6R due to adverse events. Of 70 evaluable patients by RECIST (Response Evaluation Criteria in Solid Tumors) V.1.1 criteria; the ORR was 66% prior versus 66% after anti-IL-6R (95% CI, 54% to 77%), with 8% higher complete response rate. Of 34 evaluable patients with melanoma, the ORR was 56% prior and increased to 68% after anti-IL-6R (p=0.04). CONCLUSION: Targeting IL-6R could be an effective approach to treat several irAE types without hindering antitumor immunity. This study supports ongoing clinical trials evaluating the safety and efficacy of tocilizumab (anti-IL-6R antibody) in combination with ICIs (NCT04940299, NCT03999749).

Extension of Lung Damage at Chest Computed Tomography in Severely Ill COVID-19 Patients Treated with Interleukin-6 Receptor Blockers Correlates with Inflammatory Cytokines Production and Prognosis.

Elevated inflammatory markers are associated with severe coronavirus disease 2019 (COVID-19), and some patients benefit from Interleukin (IL)-6 pathway inhibitors. Different chest computed tomography (CT) scoring systems have shown a prognostic value in COVID-19, but not specifically in anti-IL-6-treated patients at high risk of respiratory failure. We aimed to explore the relationship between baseline CT findings and inflammatory conditions and to evaluate the prognostic value of chest CT scores and laboratory findings in COVID-19 patients specifically treated with anti-IL-6. Baseline CT lung involvement was assessed in 51 hospitalized COVID-19 patients naive to glucocorticoids and other immunosuppressants using four CT scoring systems. CT data were correlated with systemic inflammation and 30-day prognosis after anti-IL-6 treatment. All the considered CT scores showed a negative correlation with pulmonary function and a positive one with C-reactive protein (CRP), IL-6, IL-8, and Tumor Necrosis Factor α (TNF-α) serum levels. All the performed scores were prognostic factors, but the disease extension assessed by the six-lung-zone CT score (S24) was the only independently associated with intensive care unit (ICU) admission (p = 0.04). In conclusion, CT involvement correlates with laboratory inflammation markers and is an independent prognostic factor in COVID-19 patients representing a further tool to implement prognostic stratification in hospitalized patients.

Consensus statement on blocking interleukin-6 receptor and interleukin-6 in inflammatory conditions: an update.

BACKGROUND: Targeting interleukin (IL)-6 has become a major therapeutic strategy in the treatment of immune-mediated inflammatory disease. Interference with the IL-6 pathway can be directed at the specific receptor using anti-IL-6Rα antibodies or by directly inhibiting the IL-6 cytokine. This paper is an update of a previous consensus document, based on most recent evidence and expert opinion, that aims to inform on the medical use of interfering with the IL-6 pathway. METHODS: A systematic literature research was performed that focused on IL-6-pathway inhibitors in inflammatory diseases. Evidence was put in context by a large group of international experts and patients in a subsequent consensus process. All were involved in formulating the consensus statements, and in the preparation of this document. RESULTS: The consensus process covered relevant aspects of dosing and populations for different indications of IL-6 pathway inhibitors that are approved across the world, including rheumatoid arthritis, polyarticular-course and systemic juvenile idiopathic arthritis, giant cell arteritis, Takayasu arteritis, adult-onset Still's disease, Castleman's disease, chimeric antigen receptor-T-cell-induced cytokine release syndrome, neuromyelitis optica spectrum disorder and severe COVID-19. Also addressed were other clinical aspects of the use of IL-6 pathway inhibitors, including pretreatment screening, safety, contraindications and monitoring. CONCLUSIONS: The document provides a comprehensive consensus on the use of IL-6 inhibition to treat inflammatory disorders to inform healthcare professionals (including researchers), patients, administrators and payers.

The effect of targeted rheumatoid arthritis therapeutics on systemic inflammation and anemia: analysis of data from the CorEvitas RA registry.

BACKGROUND: To evaluate the effects of tumor necrosis factor inhibitors (TNFi), interleukin-6 receptor inhibitors (IL-6Ri), and Janus kinase inhibitors (JAKi) on hemoglobin (Hb) and C-reactive protein (CRP) levels in adults enrolled in CorEvitas (formerly Corrona), a large US rheumatoid arthritis (RA) registry. METHODS: Patients who initiated TNFi, IL-6Ri, or JAKi treatment during or after January 2010, had Hb and CRP measurements at baseline and 6-month follow-up (± 3 months) and had continued therapy at least until that follow-up, through March 2020, were included in the analysis. Changes in Hb and CRP were assessed at month 6. Abnormal Hb was defined as < 12 g/dL (women) or < 13 g/dL (men); abnormal CRP was ≥ 0.8 mg/dL. Differences in Hb and CRP levels were evaluated using multivariable regression. RESULTS: Of 2772 patients (TNFi, 65%; IL-6Ri, 17%; JAKi, 17%) evaluated, 1044 (38%) had abnormal Hb or CRP at initiation; an additional 252 (9%) had both abnormal Hb and CRP. At month 6, the IL-6Ri group had a greater Hb increase than the TNFi (mean difference in effect on Hb: 0.28 g/dL; 95% CI 0.19-0.38) and JAKi (mean difference in effect on Hb: 0.47 g/dL; 95% CI 0.35-0.58) groups, regardless of baseline Hb status (both p < 0.001). The CRP decrease at month 6 was greater with IL-6Ri compared with TNFi and JAKi, regardless of baseline CRP status (both p < 0.05). CONCLUSION: These real-world results align with the mechanism of IL-6R inhibition and may inform treatment decisions for patients with RA.

[Three cases of hemodiafiltration for the treatment of CAR-T related grade 3 - 4 cytokine release syndrome after ineffective treatment with IL-6 receptor inhibitors].

Objective: To investigate the efficacy and safety of hemodiafiltration (HDF) in treating CAR-T related grade 3-4 cytokine release syndrome after ineffective treatment with IL-6 receptor inhibitors. Methods: Between July 2015 and July 2021, retrospective analysis of hemodiafiltration for the treatment of 3 patients, including 2 cases of acute B-lymphoblastic leukemia and 1 case of diffuse large B-cell lymphoma, with grade 3-4 CRS after CAR-T cell therapy and ineffective treatment with IL-6 receptor inhibitor was carried out. Results: The patient's clinical symptoms, including body temperature, blood pressure, and blood oxygen, were relieved within 12 hours of all treatments, and the cytokines (IL-6, IL-10, TNF-α, INF-γ) and C-reactive protein (CRP) levels decreased significantly. No adverse side effects were observed during the follow-up period of 3 months. Conclusion: HDF can be a safe and feasible method to treat CAR-T related grade 3- 4 CRS after ineffective treatment with IL-6 receptor inhibitors.

cGAS-STING drives the IL-6-dependent survival of chromosomally instable cancers.

Chromosomal instability (CIN) drives cancer cell evolution, metastasis and therapy resistance, and is associated with poor prognosis1. CIN leads to micronuclei that release DNA into the cytoplasm after rupture, which triggers activation of inflammatory signalling mediated by cGAS and STING2,3. These two proteins are considered to be tumour suppressors as they promote apoptosis and immunosurveillance. However, cGAS and STING are rarely inactivated in cancer4, and, although they have been implicated in metastasis5, it is not known why loss-of-function mutations do not arise in primary tumours4. Here we show that inactivation of cGAS-STING signalling selectively impairs the survival of triple-negative breast cancer cells that display CIN. CIN triggers IL-6-STAT3-mediated signalling, which depends on the cGAS-STING pathway and the non-canonical NF-κB pathway. Blockade of IL-6 signalling by tocilizumab, a clinically used drug that targets the IL-6 receptor (IL-6R), selectively impairs the growth of cultured triple-negative breast cancer cells that exhibit CIN. Moreover, outgrowth of chromosomally instable tumours is significantly delayed compared with tumours that do not display CIN. Notably, this targetable vulnerability is conserved across cancer types that express high levels of IL-6 and/or IL-6R in vitro and in vivo. Together, our work demonstrates pro-tumorigenic traits of cGAS-STING signalling and explains why the cGAS-STING pathway is rarely inactivated in primary tumours. Repurposing tocilizumab could be a strategy to treat cancers with CIN that overexpress IL-6R.

2-Deoxy-d-glucose induces deglycosylation of proinflammatory cytokine receptors and strongly reduces immunological responses in mouse models of inflammation.

Anti-proinflammatory cytokine therapies against interleukin (IL)-6, tumor necrosis factor (TNF)-α, and IL-1 are major advancements in treating inflammatory diseases, especially rheumatoid arthritis. Such therapies are mainly performed by injection of antibodies against cytokines or cytokine receptors. We initially found that the glycolytic inhibitor 2-deoxy-d-glucose (2-DG), a simple monosaccharide, attenuated cellular responses to IL-6 by inhibiting N-linked glycosylation of the IL-6 receptor gp130. Aglycoforms of gp130 did not bind to IL-6 or activate downstream intracellular signals that included Janus kinases. 2-DG completely inhibited dextran sodium sulfate-induced colitis, a mouse model for inflammatory bowel disease, and alleviated laminarin-induced arthritis in the SKG mouse, an experimental model for human rheumatoid arthritis. These diseases have been shown to be partially dependent on IL-6. We also found that 2-DG inhibited signals for other proinflammatory cytokines such as TNF-α, IL-1ß, and interferon -γ, and accordingly, prevented death by another inflammatory disease, lipopolysaccharide (LPS) shock. Furthermore, 2-DG prevented LPS shock, a model for a cytokine storm, and LPS-induced pulmonary inflammation, a model for acute respiratory distress syndrome of coronavirus disease 2019 (COVID-19). These results suggest that targeted therapies that inhibit cytokine receptor glycosylation are effective for treatment of various inflammatory diseases.

Clinical outcomes after IL-6 blockade in patients with COVID-19 and HIV: a case series.

BACKGROUND: In hospitalized people with HIV (PWH) there is an increased risk of mortality from COVID-19 among hospitalized PWH as compared to HIV-negative individuals. Evidence suggests that tocilizumab-a humanized monoclonal interleukin (IL)-6 receptor inhibitor (IL-6ri) antibody-has a modest mortality benefit when combined with corticosteroids in select hospitalized COVID-19 patients who are severely ill. Data on clinical outcomes after tocilizumab use in PWH with severe COVID-19 are lacking. CASE PRESENTATION: We present a multinational case series of 18 PWH with COVID-19 who were treated with IL-6ri's during the period from April to June 2020. Four patients received tocilizumab, six sarilumab, and eight received an undocumented IL-6ri. Of the 18 patients in the series, 4 (22%) had CD4 counts < 200 cells/mm3; 14 (82%) had a suppressed HIV viral load. Eight patients (44%), all admitted to ICU, were treated for secondary infection; 5 had a confirmed organism. Of the four patients with CD4 counts < 200 cells/mm3, three were treated for secondary infection, with 2 confirmed organisms. Overall outcomes were poor-12 patients (67%) were admitted to the ICU, 11 (61%) required mechanical ventilation, and 7 (39%) died. CONCLUSIONS: In this case series of hospitalized PWH with COVID-19 and given IL-6ri prior to the common use of corticosteroids, there are reports of secondary or co-infection in severely ill patients. Comprehensive studies in PWH, particularly with CD4 counts < 200 cells, are warranted to assess infectious and other outcomes after IL-6ri use, particularly in the context of co-administered corticosteroids.

Palladium Nanoplate-Based IL-6 Receptor Antagonists Ameliorate Cancer-Related Anemia and Simultaneously Inhibit Cancer Progression.

In recent years, targeted therapies and immunotherapeutics, along with conventional chemo- and radiotherapy, have greatly improved cancer treatments. Unfortunately, in cancer patients, anemia, either as a complication of cancer progression or as the result of cancer treatment, undermines the expected therapeutic efficacy. Here, we developed a smart nanosystem based on the palladium nanoplates (PdPLs) to deliver tocilizumab (TCZ, a widely used IL-6R antibody) to the liver for specific blockade of IL-6/IL-6R signaling to correct anemia. With chemical modifications, this nanosystem delivered a large mass of TCZ and enhanced liver delivery, inducing a marked suppression of hepcidin expression as a result of diminished IL-6 signaling. Through this mechanism, significant suppression of tumor progression was realized (at least in part) because of the corrected anemia after treatment.

Interleukin-6 Receptor Blockade in Treatment-Refractory MOG-IgG-Associated Disease and Neuromyelitis Optica Spectrum Disorders.

BACKGROUND AND OBJECTIVES: To evaluate the long-term safety and efficacy of tocilizumab (TCZ), a humanized anti-interleukin-6 receptor antibody in myelin oligodendrocyte glycoprotein-IgG-associated disease (MOGAD) and neuromyelitis optica spectrum disorders (NMOSD). METHODS: Annualized relapse rate (ARR), Expanded Disability Status Scale score, MRI, autoantibody titers, pain, and adverse events were retrospectively evaluated in 57 patients with MOGAD (n = 14), aquaporin-4 (AQP4)-IgG seropositive (n = 36), and seronegative NMOSD (n = 7; 12%), switched to TCZ from previous immunotherapies, particularly rituximab. RESULTS: Patients received TCZ for 23.8 months (median; interquartile range 13.0-51.1 months), with an IV dose of 8.0 mg/kg (median; range 6-12 mg/kg) every 31.6 days (mean; range 26-44 days). For MOGAD, the median ARR decreased from 1.75 (range 0.5-5) to 0 (range 0-0.9; p = 0.0011) under TCZ. A similar effect was seen for AQP4-IgG+ (ARR reduction from 1.5 [range 0-5] to 0 [range 0-4.2]; p < 0.001) and for seronegative NMOSD (from 3.0 [range 1.0-3.0] to 0.2 [range 0-2.0]; p = 0.031). During TCZ, 60% of all patients were relapse free (79% for MOGAD, 56% for AQP4-IgG+, and 43% for seronegative NMOSD). Disability follow-up indicated stabilization. MRI inflammatory activity decreased in MOGAD (p = 0.04; for the brain) and in AQP4-IgG+ NMOSD (p < 0.001; for the spinal cord). Chronic pain was unchanged. Regarding only patients treated with TCZ for at least 12 months (n = 44), ARR reductions were confirmed, including the subgroups of MOGAD (n = 11) and AQP4-IgG+ patients (n = 28). Similarly, in the group of patients treated with TCZ for at least 12 months, 59% of them were relapse free, with 73% for MOGAD, 57% for AQP4-IgG+, and 40% for patients with seronegative NMOSD. No severe or unexpected safety signals were observed. Add-on therapy showed no advantage compared with TCZ monotherapy. DISCUSSION: This study provides Class III evidence that long-term TCZ therapy is safe and reduces relapse probability in MOGAD and AQP4-IgG+ NMOSD.

The informative value of CD3+CD4+ and CD3+CD8+ T-cell count and cHIS scale as predictors of severe COVID-19 when using interleukin-6 receptor blockers in the in-hospital setting.

BACKGROUND: Clinical and laboratory signs of hyperinflammatory response in COVID-19 may serve as prognostic markers of the disease scenario. In real-world practice, there is an unmet need to determine the optimal timing of identifying predictors of SARS-CoV-2 adverse outcomes in the context of patient stratification to improve the effectiveness of anti-IL-6R therapy. Lymphopenia has a high informative value for the adverse prognosis of the COVID-19 course; however, the informative value of CD3+CD4+, CD3+CD8+ T-cell count remains questionable. In addition to lymphocyte phenotyping, a six-criterion additive scale (cHIS) was used in the study. AIM: To study the informative value of CD3+CD4+, CD3+CD8+ T-cell phenotyping and cHIS scale as predictors of severe COVID-19 when using IL-6R blockers. MATERIALS AND METHODS: A single-center, bi-directional study included 179 patients with SARS-CoV-2-induced community-acquired pneumonia with severe acute inflammation and progressing respiratory failure. Data were obtained from electronic patient records. Anti-IL-6R was administered in addition to standard therapy in the cohorts. The following disease outcomes were used to determine the informative value of the studied parameters: mortality and hospital discharge. Inflammatory markers were measured before and after administering anti-IL-6R, followed by monitoring. Statistical analysis was performed using SPSS (version 25.0). The quantitative indices were described using the median and interquartile range. Quantitative indices were compared using nonparametric methods: Mann-Whitney U-test, Kruskal-Wallis test. The groups were compared by qualitative characteristics using Pearson's chi-square test. Correlation analysis of quantitative indicators was performed using Spearman rank correlation. For additional analysis of the cHIS scale, odds ratio and decision tree methods were used. Differences were considered statistically significant at р≤0,05. RESULTS: Immunophenotyping of lymphocytes as a predictor of the severe SARS-CoV-2 requires further research. The cHIS scale may be implemented in routine clinical practice due to its high predictive value. A cHIS score of ≥2 on the first day of admission is a critical threshold for intensification and revision of therapy. The prognosis with cHIS is logically relevant in the first three days of hospitalization. CONCLUSION: The main result of the study is the definition of target groups of patients with community-acquired SARS-CoV-2 pneumonia for the IL-6R-blockers, considering the timing of their effective use in real clinical practice.

The activation fragment of PAR2 is elevated in serum from patients with rheumatoid arthritis and reduced in response to anti-IL6R treatment.

Osteoarthritis (OA) and rheumatoid arthritis (RA) are serious and painful diseases. Protease-activated receptor 2 (PAR2) is involved in the pathology of both OA and RA including roles in synovial hyperplasia, cartilage destruction, osteophyogenesis and pain. PAR2 is activated via cleavage of its N-terminus by serine proteases. In this study a competitive ELISA assay was developed targeting the 36-amino acid peptide that is cleaved and released after PAR2 activation (PRO-PAR2). Technical assay parameters including antibody specificity, intra- and inter-assay variation (CV%), linearity, accuracy, analyte stability and interference were evaluated. PRO-PAR2 release was confirmed after in vitro cleavage of PAR2 recombinant protein and treatment of human synovial explants with matriptase. Serum levels of 22 healthy individuals, 23 OA patients and 15 RA patients as well as a subset of RA patients treated with tocilizumab were evaluated. The PRO-PAR2 antibody was specific for the neo-epitope and intra-inter assay CV% were 6.4% and 5.8% respectively. In vitro cleavage and matriptase treated explants showed increased PRO-PAR2 levels compared to controls. In serum, PRO-PAR2 levels were increased in RA patients and decreased in RA patients treated with tocilizumab. In conclusion, PRO-PAR2 may be a potential biomarker for monitoring RA disease and pharmacodynamics of treatment.

Safety and efficacy of interleukin-6-receptor inhibitors in the treatment of neuromyelitis optica spectrum disorders: a meta-analysis.

BACKGROUND: Interleukin-6-receptor inhibitors like Tocilizumab and Satralizumab are showing promising results in the treatment of Neuromyelitis Optica spectrum disorder (NMOSD). We aimed to investigate the efficacy and safety of various Interleukin-6-receptor inhibitors in the management of NMO/NMOSD. METHODS: PubMed, Embase, and The Cochrane Library were systematically searched for suitable studies. Change in Annualized Relapse Ratio (ARR), Change in Extended Disability Status Scale (EDSS) s, the proportion of relapse-free patients and proportion of patients with adverse events, including serious adverse events and mortality were the parameters considered for the meta-analysis for Tocilizumab. Mean difference (MD) with 95% CI was used to quantify the change in ARR and change in EDSS before and after treatment. A forest plot was prepared to indicate the efficacy and adverse effects outcomes. The results were compared with those of Satralizumab included in two trials. RESULTS: A total of nine studies with 202 patients were included in our study. Tocilizumab found a good proportion (76.95% CI: 0.61-0.91; p < 0.001) of relapse free patients at follow up. It also significantly reduced mean ARR (mean difference: -2.6, 95% CI: - 2.71 to - 1.68; p < 0.001) and but did not show significant difference in change in EDSS score (mean difference = - 0.79, 95% CI: - 1.89 to - 0.31; p = 0.16). Also, the toxicity profile of Tocilizumab was acceptable considering the proportions of patients with adverse events 56% (95% C.I.;0.27-0.85, I2 = 88.95%, p < 0.001), proportions of patients with serious adverse events 11% (95% C.I.; 0.05 to 0.17, I2 = 0%, p < 0.001) and zero treatment related deaths. SAkura studies for Satralizumab showed similar relapse free patients (70% to 80%) and reduction of ARR and EDSS from baseline. Some studies of Tocilizumab have shown to reduce pain and fatigue while trials of Satralizumab had non-significant findings. CONCLUSION: Interleukin-6-receptor inhibitors therapy showed a promising result with good efficacy and acceptable adverse events profile for treatment of NMOSD.

Blockade of IL-6/IL-6R Signaling Attenuates Acute Antibody-Mediated Rejection in a Mouse Cardiac Transplantation Model.

Acute antibody-mediated rejection (AAMR) is an important cause of cardiac allograft dysfunction, and more effective strategies need to be explored to improve allograft prognosis. Interleukin (IL)-6/IL-6R signaling plays a key role in the activation of immune cells including B cells, T cells and macrophages, which participate in the progression of AAMR. In this study, we investigated the effect of IL-6/IL-6R signaling blockade on the prevention of AAMR in a mouse model. We established a mouse model of AAMR for cardiac transplantation via presensitization of skin grafts and addition of cyclosporin A, and sequentially analyzed its features. Tocilizumab, anti-IL-6R antibody, and recipient IL-6 knockout were used to block IL-6/IL-6R signaling. We demonstrated that blockade of IL-6/IL-6R signaling significantly attenuated allograft injury and improved survival. Further mechanistic research revealed that signaling blockade decreased B cells in circulation, spleens, and allografts, thus inhibiting donor-specific antibody production and complement activation. Moreover, macrophage, T cell, and pro-inflammatory cytokine infiltration in allografts was also reduced. Collectively, we provided a highly practical mouse model of AAMR and demonstrated that blockade of IL-6/IL-6R signaling markedly alleviated AAMR, which is expected to provide a superior option for the treatment of AAMR in clinic.