Recombinant Interleukin-1 Receptor Antagonist Research Articles

Reduction of mortality, cardiac damage, and cerebral damage by IL-1 inhibition in a murine model of TTP

AbstractThrombotic thrombocytopenic purpura (TTP), a rare but fatal disease if untreated, is due to alteration in von Willebrand factor cleavage resulting in capillary microthrombus formation and ischemic organ damage. Interleukin-1 (IL-1) has been shown to drive sterile inflammation after ischemia and could play an essential contribution to postischemic organ damage in TTP. Our objectives were to evaluate IL-1 involvement during TTP and to test the efficacy of the recombinant IL-1 receptor antagonist, anakinra, in a murine TTP model. We retrospectively measured plasmatic IL-1 concentrations in patients with TTP and controls. Patients with TTP exhibited elevated plasma IL-1α and -1β concentrations, which correlated with disease course and survival. In a mouse model of TTP, we administered anakinra (IL-1 inhibitor) or placebo for 5 days and evaluated the efficacy of this treatment. Anakinra significantly reduced mortality of mice (P < .001). Anakinra significantly decreased TTP-induced cardiac damages as assessed by blood troponin concentrations, evaluation of left ventricular function by echocardiography, [18F]fluorodeoxyglucose positron emission tomography of myocardial glucose metabolism, and cardiac histology. Anakinra also significantly reduced brain TTP-induced damages evaluated through blood PS100b concentrations, nuclear imaging, and histology. We finally showed that IL-1α and -1β trigger endothelial degranulation in vitro, leading to the release of von Willebrand factor. In conclusion, anakinra significantly reduced TTP mortality in a preclinical model of the disease by inhibiting both endothelial degranulation and postischemic inflammation, supporting further evaluations in humans.

Abstract 5516: Aberrant activation and perpetuation of lung wound response facilitates osteosarcoma metastasis

Abstract Introduction: The mechanisms that allow tumor cells to integrate with unfamiliar parenchymal cells within hostile distant tissues during metastatic colonization remain poorly defined. Nowhere are these mechanisms more important than in osteosarcoma-a pediatric bone tumor where metastases cause nearly all osteosarcoma related deaths and occur almost exclusively in the lung. The purpose of this study was to define the cellular and molecular events that facilitate osteosarcoma lung colonization to devise novel therapeutic strategies that prevent and treat metastasis. Experimental Approach: We generated experimental lung metastases using a panel of immunocompetent murine and human xenograft osteosarcoma models. A combination of immunohistochemistry, single cell RNA sequencing, and spatial transcriptomics were used to define the metastatic niche. Relevant findings were validated in human primary tumor, lung metastasis, and normal lung tissue specimens. Results: Disseminated osteosarcoma cells physically associate with alveolar epithelial cells and trigger changes in surrounding epithelial cells that are characteristic of the aberrant, non-resolving wound response seen in non-malignant lung diseases such as idiopathic pulmonary fibrosis (IPF). This process drives the accumulation of fibrotic epithelial cells and scar-associated macrophages confined within a dense fibronectin-based matrix. Anti-fibrotic tyrosine kinase inhibitors used to treat patients with IPF (nintedanib) prevent the observed fibrogenic changes and inhibit metastatic colonization. Epithelial-osteosarcoma paracrine signaling is dominated by an inflammatory cytokine milieu that facilitates this transition towards fibrosis. Blocking one of the dominant paracrine signals with a recombinant IL1 receptor antagonist (anakinra) has similar effects on both fibrosis and metastatic colonization. Conclusions: Our study demonstrates that tumor interactions with host stromal cells are critical for metastasis. Metastatic colonization requires transformation of the local lung microenvironment into a fibrotic, non-resolving, cytokine-rich, wound-like state that is both provoked and sustained by tumor-epithelial interactions. These insights have identified several potential therapeutic approaches to prevent metastatic colonization and treat established metastases. Citation Format: James Brandon Reinecke, Amy C. Gross, Maren Cam, Leyre Jimenez Garcia, Matthew V. Cannon, Ryan D. Roberts. Aberrant activation and perpetuation of lung wound response facilitates osteosarcoma metastasis [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 5516.

Does your unwell patient have haemophagocytic lymphohistiocytosis?

Haemophagocytic lymphohistiocytosis is a severe systemic hyperinflammatory syndrome characterised by dysregulation of immune cells and excessive production of cytokines, also known as a cytokine storm. It has distinctive clinical features with fever, hyperferritinaemia and falling blood counts. In adults, this usually occurs secondary to an underlying driver or trigger including infection, malignancy or rheumatic diseases. Prompt treatment with immunomodulatory therapy, including corticosteroids and the recombinant IL-1 receptor antagonist anakinra, is recommended to switch off the cytokine storm. Etoposide-based regimens are sometimes needed, and newer therapies such as emapalumab and JAK inhibitors are increasingly being used. The incidence of haemophagocytic lymphohistiocytosis has increased significantly over the last 20 years which may partly reflect increased awareness of the condition. Although relatively rare, haemophagocytic lymphohistiocytosis can be encountered by a broad range of hospital physicians, so knowing how to diagnose and treat this condition is essential. This article reviews the pathogenesis, clinical features, causes, diagnosis and treatment of haemophagocytic lymphohistiocytosis to improve physician recognition and management of this condition to improve future patient outcomes.

Study of chondroprotective properties of interleukin-1 receptor antagonist.

Osteoarthritis is one of the most widespread diseases, represents a medical and socio-economic problem and is one of the first places among the causes of long-term disability of the population in the world. Cytokine mechanisms of osteoarthritis development are attracting more and more attention.&#x0D; The aim of the study was to determine the chondroprotective and anti-inflammatory properties of the original recombinant interleukin-1 (IL-1) receptor antagonist (ARIL-1) raleukin on the model of systemic steroid osteoarthritis (SSO) in rats.&#x0D; Materials and methods. The SSO model was reproduced in a modified form by intramuscular three-time administration of dexamethasone at a dose of 7 mg/kg with an interval of one week. Raleukin was injected subcutaneously in a conditionally effective dose of 3 mg/kg for anti-inflammatory activity, and glucosamine (GA) orally in a dose of 50 mg/kg (ED50 for anti-inflammatory activity). Starting from the 28th day of the study and for 4 weeks, the study objects were introduced by the appropriate route once a day.&#x0D; Result. The results of the experiment show that clinical signs of damage to the locomotor system appeared in all animals after three administrations of dexamethasone. Later and before the end of the experiment, a typical clinical picture of the development of SSO was observed, which was confirmed by the results of the study of biochemical markers (mainly in blood serum) of the state of the connective tissue of the experimental animals.&#x0D; Significant changes in the functional status of the animals were noted in rats with SSO who received raleukin starting from the second week of administration. In rats, motor activity increased, tolerance to physical exertion increased, joint condition visually normalised, and appetite increased. When the reference drug GA was administered, the functional state of the animals differed from the control pathology group to a somewhat lesser extent. Besides, raleukin did not reliably differ from GA in its effect on biochemical parameters characterising the state of connective tissue and the content of its main metabolites in the blood serum of rats with steroid osteoarthritis.&#x0D; Conclusions. In the model of systemic steroid osteoarthritis, raleukin contributed to the improvement of functional indicators of the condition of animals and the normalisation of their body weight; namely, it moderately reduced the content of all markers of connective tissue metabolism in the blood serum of animals, especially chondroitin sulfates and sialic acids, which can be explained by the systemic nature of its effect. In terms of its effect on the level of the main metabolites of connective tissue in the blood serum of rats, raleukin prevailed over glucosamine hydrochloride. Thus, the analysis of biochemical data against the background of experimental osteoarthritis allows us to draw a conclusion about the high chondroprotective and anti-inflammatory potential of the recombinant IL-1 receptor antagonist

Analysis of Anakinra Therapy for the Deficiency of Interleukin-1 Receptor Antagonist through Clinical Evidence.

Deficiency of interleukin-1 receptor antagonist (DIRA) is a rare life-threatening autosomal recessive autoinflammatory disease with symptoms including but not limited to osteomyelitis, periostitis, and systemic inflammation. DIRA is developed from the loss-of-function biallelic mutations of the IL1RN gene that encodes IL-1 receptor antagonist (IL-1RA), leading to the unchecked pro-inflammatory signaling and subsequent systemic inflammation. Thus, anakinra as the recombinant IL-1RA has become the primary drug to treat DIRA. Although anakinra has been effective for the complete remission of DIRA, it has also shown various side effects. To confirm the efficacy and safety issues associated with DIRA treatment, we conducted a literature review and secondary data analysis to enhance our understanding on this important topic. Through comprehensive literature search, we have identified 15 papers with 25 patients studied. The demographic, clinical, and genetic data were extracted, followed by statistical analysis to support the physiological mechanisms of anakinra treatment. Through the literature review and data analysis, it was found that 88% of patients had complete clinical remission of DIRA upon continual treatment with anakinra; patients had a mean improvement of Hemoglobin (+3.18 g/dL), Erythrocyte Sedimentation Rate (-53.4 mm/h), and C-reactive Protein (-135.45 mg/L) levels, suggesting that the improvement of hematopoietic function and inflammation is a mechanism for anakinra treatment. Various genetic variants were also identified from the patient data that cause the loss of function of IL-1RA, providing real patient genomic data to support the anakinra treatment. Considering the inconsistency and certain variations from clinical research influenced by specific conditions, this review along with the data analysis confirms the efficacy and safety of anakinra treatment for DIRA.

Phase 2 Study of Anakinra to Prevent CRS and Neurotoxicity after Treatment with Lisocabtagene Maraleucel: Planned Interim Analysis

BACKGROUND CD19 chimeric antigen receptor (CAR) T-cell therapies have transformed the treatment landscape for patients (pts) with relapsed/refractory B-cell malignancies, but they remain limited by significant toxicities: cytokine release syndrome (CRS) and immune effector cell-associated neurotoxicity syndrome (ICANS). While a more favorable toxicity profile had been reported with lisocabtagene maraleucel (liso-cel), based on our real-world experience CRS and ICANS are still observed in 70% and 30% of pts, respectively (Portuguese et al., ASH abstract #172978). Data from our group (Gazeau, TCT, 2023) and others (Strati, Blood, 2023; Park, Nat Med, 2023) suggested the recombinant interleukin-1 receptor antagonist anakinra may successfully prevent and treat CRS and ICANS. Thus, we conducted a phase 2 investigator-initiated clinical trial of anakinra to prevent CRS and ICANS after liso-cel (NCT04359784). We report here our planned interim analysis (n = 15). METHODS Adults ≥18 years of age with Karnofsky performance status ≥60% and B-cell non-Hodgkin lymphoma receiving liso-cel per the FDA label were eligible for this study. Anakinra was administered at 200 mg/day SC from day 0 through day +13 after liso-cel infusion, with the first dose administered approximately 2-4 hours prior to liso-cel infusion. CRS and ICANS severity were assessed per 2019 ASTCT criteria. The primary endpoint was the absence of any grade CRS assessed using the Bayesian optimal phase 2 design.The primary endpoint was not met if ≥6 of the first 15 pts developed any grade CRS. RESULTS Nineteen pts were screened for the study and 15 pts were enrolled. All 15 pts received liso-cel and all doses of SC anakinra. All pts were evaluable for toxicity assessment; 12 pts were evaluable for disease response assessment at day +28 (n = 3, no measurable disease prior to lymphodepletion [LD]). Pt and disease characteristics are shown in Table 1. Eleven pts (73%) had diffuse large B-cell lymphoma, 3 (20%) had active CNS involvement, and 5 (33%) had bulky disease (≥5 cm). Median pre-LD serum ferritin and C-reactive protein (CRP) were 153 ng/mL (IQR, 129-231) and 6.8 (IQR, 1.5-17.2), respectively. All 15 pts received anakinra as planned without dose adjustment or interruption. There were no injection-site reactions or AEs attributed to anakinra. Two pts developed infections during anakinra treatment and were both due to mild Clostridium difficile colitis requiring oral antibiotics. Eight pts (53%) developed any grade CRS, including 1 (7%) case of grade 3 CRS. Four pts (27%) developed any grade ICANS, including 3 (20%) with grade 3 (Figure 1). Median CRS onset and duration were 2 and 2.5 days, respectively, and median ICANS onset and duration were 6 and 9 days, respectively. Three pts (20%) required tocilizumab (range, 0-1 doses), 4 (50%) required dexamethasone (median total dose, 5 mg; range, 0-200 mg), and 1 (12%) required high-dose methylprednisolone. The best overall response rate (ORR) by Lugano criteria was 67% (complete response, n = 5 [42%]). Study pts were retrospectively compared to pts who received liso-cel per standard of care off trial without prophylactic anakinra at our center (n = 42). Despite higher median pre-LD CRP and IL-6 levels, the incidence of CRS was lower in anakinra-treated compared to anakinra-untreated pts (53% vs. 69%, respectively) with comparable median duration of CRS (2.5 vs. 3 days, respectively). The incidence and duration of ICANS were similar (27% vs. 28%; median 9 vs. 8 days, respectively), as was the incidence and duration of hospitalization (67% vs. 74%, median 9.5 vs. 10 days, respectively). Based on Locally Estimated Scatterplot Smoothing (LOESS) estimates, time from liso-cel infusion to CRP normalization was faster in patients receiving anakinra (9 days) compared to those receiving liso-cel alone (14 days). CONCLUSION Low-dose SC anakinra prophylaxis during liso-cel treatment was very well tolerated with preserved anti-tumor efficacy. While our primary endpoint was not reached at our planned interim analysis, we observed lower CRS rates and faster resolution of CRS in comparison to a real-world cohort of pts receiving liso-cel without prophylactic anakinra. To further enhance the preventative effects of anakinra, we plan to change the administration route from SC to intravenous, and to allow anakinra dose uptitration for the last 10 participants in the study.

Tension-activated nanofiber patches delivering an anti-inflammatory drug improve repair in a goat intervertebral disc herniation model.

Conventional microdiscectomy treatment for intervertebral disc herniation alleviates pain but does not repair the annulus fibrosus, resulting in a high incidence of recurrent herniation and persistent dysfunction. The lack of repair and the acute inflammation that arise after injury can further compromise the disc and result in disc-wide degeneration in the long term. To address this clinical need, we developed tension-activated repair patches (TARPs) for annulus fibrosus repair and local delivery of the anti-inflammatory factor anakinra (a recombinant interleukin-1 receptor antagonist). TARPs transmit physiologic strain to mechanically activated microcapsules embedded within the patch, which release encapsulated bioactive molecules in direct response to spinal loading. Mechanically activated microcapsules carrying anakinra were loaded into TARPs, and the effects of TARP-mediated annular repair and anakinra delivery were evaluated in a goat model of annular injury in the cervical spine. TARPs integrated with native tissue and provided structural reinforcement at the injury site that prevented aberrant disc-wide remodeling resulting from detensioning of the annular fibrosus. The delivery of anakinra by TARP implantation increased matrix deposition and retention at the injury site and improved maintenance of disc extracellular matrix. Anakinra delivery additionally attenuated the inflammatory response associated with TARP implantation, decreasing osteolysis in adjacent vertebrae and preserving disc cellularity and matrix organization throughout the annulus fibrosus. These results demonstrate the therapeutic potential of TARPs for the treatment of intervertebral disc herniation.

Recombinant Interleukin-1 Receptor Antagonist Is an Effective First-Line Treatment Strategy in New-Onset Systemic Juvenile Idiopathic Arthritis, Irrespective of HLA-DRB1 Background and IL1RN Variants.

Human leukocyte antigen (HLA)-DRB1*15:01 has been recently associated with interstitial lung disease (LD), eosinophilia, and drug reactions in systemic juvenile idiopathic arthritis (sJIA). Additionally, genetic variants in IL1RN have been linked to poor response to anakinra. We sought to reproduce these findings in a prospective cohort study of patients with new-onset sJIA treated with anakinra as first-line therapy. HLA and IL1RN risk alleles were identified via whole-genome sequencing. Treatment responses and complications were compared between carriers versus noncarriers. Seventeen of 65 patients (26%) carried HLA-DRB1*15:01, comparable with the general population, and there was enrichment for HLA-DRB1*11:01, a known risk locus for sJIA. The rates of clinical inactive disease (CID) at 6 months, 1 year, and 2 years were generally high, irrespective of HLA-DRB1 or IL1RN variants, but significantly lower in carriers of an HLA-DRB1*11:01 allele. One patient, an HLA-DRB1*15:01 carrier, developed sJIA-LD. Of the three patients with severe drug reactions to biologics, one carried HLA-DRB1*15:01. The prevalence of eosinophilia did not significantly differ between HLA-DRB1*15:01 carriers and noncarriers at disease onset (6.2% vs 14.9%, P = 0.67) nor after the start of anakinra (35.3% vs 37.5% in the first 2 years of disease). We observed high rates of CID using anakinra as first-line treatment irrespective of HLA-DRB1 or IL1RN variants. Only one of the 17 HLA-DRB1*15:01 carriers developed sJIA-LD, and of the three patients with drug reactions to biologics, only one carried HLA-DRB1*15:01. Although thorough monitoring for the development of drug hypersensitivity and refractory disease courses in sJIA, including sJIA-LD, remains important, our data support the early start of biologic therapy in patients with new-onset sJIA irrespective of HLA-DRB1 background or IL1RN variants.

Anakinra and hepatotoxicity in pediatric rheumatology: a case series

BackgroundAnakinra is a recombinant interleukin-1 (IL-1) receptor antagonist used in systemic juvenile idiopathic arthritis (sJIA), refractory Kawasaki disease (KD) and cryopyrin-associated autoinflammatory syndrome (CAPS). Anakinra associated hepatotoxicity, while rare, has been described in several cases in daily practice. ​In this case series the authors describe three pediatric patients with this side effect in the setting of severe macrophage activation syndrome (MAS) in KD and sJIA.Case presentationThe first patient was a 12-year-old boy who presented with fever, maculo-papular exanthema and polyarthralgia. Tonsillitis, distal limb induration and tender cervical lymph nodes were observed. Erythrocyte-sedimentation rate (ESR), C-reactive protein (CRP), ferritin (11,975 ng/mL), D-dimers (5,98 mg/L FEU) and soluble CD25 (3645 pg/mL) levels were elevated. Exclusion of sepsis / toxic shock syndrome warranted introduction of IV methylprednisolone and immunoglobulin (IG IV), with partial response. A MAS secondary to KD was assumed, and anakinra 2 mg/kg/day was introduced. Twenty days later he developed new-onset nausea and severe cyto-cholestasis, normalizing after 2 months of drug discontinuation. Posterior onset of polyarthritis and evanescent lead to a final diagnosis of sJIA. The second patient was a 2-year-old boy with a 10-day history of fevers, generalized rash, hepatosplenomegaly and strawberry tongue. Leucocytosis with neutrophilia and elevated CRP were observed. Initial treatment with IVIG in the setting of incomplete KD was ineffective. Mild anaemia, leukopenia and very high serum ferritin (maximum 26,128 ng/mL) ensued. Presumptive sJIA associated MAS was treated with IV methylprednisolone and anakinra 2 mg/kg/day, with prompt response. Four weeks later transaminitis was detected, and temporary anakinra suspension led to normalisation of laboratorial values. The third case related to a 4-year-old boy presenting with fever, maculopapular rash and cervical lymphadenopathy. CRP and ESR were elevated, and KD was diagnosed. IVIG and methylprednisolone were initiated with clinical worsening, warranting for anakinra introduction at 2 mg/kg/day. After three weeks, liver enzymes progressively elevated, resolving on 2 weeks of anakinra discontinuation.ConclusionsTo the best of our knowledge, this is the first case series describing anakinra associated hepatotoxicity in pediatric patients with rheumatic diseases other than sJIA, bringing additional insight to therapeutic monitoring in patients undergoing this treatment.

IL-1 blockade in cardiovascular disease: an appraisal of the evidence across different inflammatory paradigms.

Pre-clinical and clinical studies suggest a role for inflammation in the pathophysiology of cardiovascular (CV) diseases. The NLRP3 (NACHT, leucine-rich repeat, and pyrin domain-containing protein 3) inflammasome is activated during tissue injury and releases interleukin-1β (IL-1β). We describe three paradigms in which the NLRP3 inflammasome and IL-1β contribute to CV diseases. During acute myocardial infarction (AMI), necrotic cell debris, including IL-1α, induce NLRP3 inflammasome activation and further damage the myocardium contributing to heart failure (HF) (acute injury paradigm). In chronic HF, IL-1β is induced by persistent myocardial overload and injury, neurohumoral activation and systemic comorbidities favoring infiltration and activation of immune cells into the myocardium, microvascular inflammation, and a pro-fibrotic response (chronic inflammation paradigm). In recurrent pericarditis, an autoinflammatory response triggered by cell injury and maintained by the NLRP3 inflammasome/IL-1β axis is present (autoinflammatory disease paradigm). Anakinra, recombinant IL-1 receptor antagonist, inhibits the acute inflammatory response in patients with ST elevation myocardial infarction (STEMI) and acute HF. Canakinumab, IL-1β antibody, blunts systemic inflammation and prevents complications of atherosclerosis in stable patients with prior AMI. In chronic HF, anakinra reduces systemic inflammation and improves cardiorespiratory fitness. In recurrent pericarditis, anakinra and rilonacept, a soluble IL-1 receptor chimeric fusion protein blocking IL-1α and IL-1β, treat and prevent acute flares. In conclusion, the NLRP3 inflammasome and IL-1 contribute to the pathophysiology of CV diseases, and IL-1 blockade is beneficial with different roles in the acute injury, chronic inflammation and autoinflammatory disease paradigms. Further research is needed to guide the optimal use of IL-1 blockers in clinical practice.

Hypertonic saline induces inflammation in human macrophages through the NLRP1 inflammasome.

Nebulized hypertonic saline (3-7%) is commonly used to increase mucociliary clearance in patients with chronic airway disease and/or virus infections. However, altered salt concentrations may contribute to inflammatory responses. The aim of this study was to investigate whether 500 mM NaCl (3%) triggers inflammation in human macrophages and identify the molecular mechanisms involved. NaCl-induced pyroptosis, IL-1β, IL-18 and ASC speck release were measured in primary human monocyte-derived macrophages. Treatment with the recombinant IL-1 receptor antagonist anakinra or the NLRP3 inhibitor MCC950 did not affect NaCl-mediated inflammasome assembly. Knock-down of NLRP1 expression, but not of NLRP3 and NLRC4, reduced NaCl-induced pyroptosis, pro-inflammatory cytokine and ASC speck release from human THP-1-derived macrophages. Data from this study suggest that 3% NaCl-induced inflammatory responses in human macrophages depend on NLRP1 and inflammasome assembly. Targeting inflammation in addition to inhalation with hypertonic saline may benefit patients with inflammatory airway disease.

Expression and characterization of recombinant IL-1Ra in Aspergillus oryzae as a system

BackgroundThe interleukin-1 receptor antagonist (IL-1Ra) is a crucial molecule that counteracts the effects of interleukin-1 (IL-1) by binding to its receptor. A high concentration of IL-1Ra is required for complete inhibition of IL-1 activity. However, the currently available Escherichia coli-expressed IL-1Ra (E. coli IL-1Ra, Anakinra) has a limited half-life. This study aims to produce a cost-effective, functional IL-1Ra on an industrial scale by expressing it in the pyrG auxotroph Aspergillus oryzae.ResultsWe purified A. oryzae-expressed IL-1Ra (Asp. IL-1Ra) using ion exchange and size exclusion chromatography (53 mg/L). Sodium dodecyl sulfate–polyacrylamide gel electrophoresis (SDS-PAGE) analysis revealed that Asp. IL-1Ra is N-glycosylated and approximately 17 kDa in size. We conducted a comparative study of the bioactivity, binding kinetics, and half-life between Asp. IL-1Ra and E. coli IL-1Ra. Asp. IL-1Ra showed good bioactivity even at a low concentration of 0.5 nM. The in vitro half-life of Asp. IL-1Ra was determined for different time points (0, 24, 48, 72, and 96 h) and showed higher stability than E. coli IL-1Ra, despite exhibiting a 100-fold lower binding affinity (2 nM).ConclusionThis study reports the production of a functional Asp. IL-1Ra with advantageous stability, without extensive downstream processing. To our knowledge, this is the first report of a recombinant functional and stable IL-1Ra expressed in A. oryzae. Our results suggest that Asp. IL-1Ra has potential for industrial-scale production as a cost-effective alternative to E. coli IL-1Ra.

NLRP3 inflammasome and interleukin-1 contributions to COVID-19-associated coagulopathy and immunothrombosis.

Immunothrombosis-immune-mediated activation of coagulation-is protective against pathogens, but excessive immunothrombosis can result in pathological thrombosis and multiorgan damage, as in severe coronavirus disease 2019 (COVID-19). The NACHT-, LRR-, and pyrin domain-containing protein 3 (NLRP3) inflammasome produces major proinflammatory cytokines of the interleukin (IL)-1 family, IL-1β and IL-18, and induces pyroptotic cell death. Activation of the NLRP3 inflammasome pathway also promotes immunothrombotic programs including release of neutrophil extracellular traps and tissue factor by leukocytes, and prothrombotic responses by platelets and the vascular endothelium. NLRP3 inflammasome activation occurs in patients with COVID-19 pneumonia. In preclinical models, NLRP3 inflammasome pathway blockade restrains COVID-19-like hyperinflammation and pathology. Anakinra, recombinant human IL-1 receptor antagonist, showed safety and efficacy and is approved for the treatment of hypoxaemic COVID-19 patients with early signs of hyperinflammation. The non-selective NLRP3 inhibitor colchicine reduced hospitalization and death in a subgroup of COVID-19 outpatients but is not approved for the treatment of COVID-19. Additional COVID-19 trials testing NLRP3 inflammasome pathway blockers are inconclusive or ongoing. We herein outline the contribution of immunothrombosis to COVID-19-associated coagulopathy, and review preclinical and clinical evidence suggesting an engagement of the NLRP3 inflammasome pathway in the immunothrombotic pathogenesis of COVID-19. We also summarize current efforts to target the NLRP3 inflammasome pathway in COVID-19, and discuss challenges, unmet gaps, and the therapeutic potential that inflammasome-targeted strategies may provide for inflammation-driven thrombotic disorders including COVID-19.

Anakinra in hospitalized COVID-19 patients guided by baseline soluble urokinase plasminogen receptor plasma levels: A real world, retrospective cohort study.

In patients with COVID-19 and baseline soluble urokinase plasminogen receptor plasma (suPAR) levels ≥ 6ng/mL, early administration of anakinra, a recombinant interleukin-1 receptor antagonist, may prevent disease progression and death. In case of suPAR testing unavailability, the Severe COvid Prediction Estimate (SCOPE) score may be used as an alternative in guiding treatment decisions. We conducted a monocenter, retrospective cohort study, including patients with SARS-CoV2 infection and respiratory failure. Patients treated with anakinra (anakinra group, AG) were compared to two control groups of patients who did not receive anakinra, respectively with ≥ 6 ng/mL (CG1) and < 6 ng/mL (CG2) baseline suPAR levels. Controls were manually paired by age, sex, date of admission and vaccination status and, for patients with high baseline suPAR, propensity score weighting for receiving anakinra was applied. Primary endpoint of the study was disease progression at day 14 from admission, as defined by patient distribution on a simplified version of the 11-point World Health Organization Clinical Progression Scale (WHO-CPS). Between July, 2021 and January, 2022, 153 patients were included, among which 56 were treated with off-label anakinra, 49 retrospectively fulfilled prescriptive criteria for anakinra and were assigned to CG1, and 48 presented with suPAR levels < 6ng/mL and were assigned to CG2. At day 14, when comparing to CG1, patients who received anakinra had significantly reduced odds of progressing towards worse clinical outcome both in ordinal regression analysis (OR 0.25, 95% CI 0.11-0.54, p<0.001) and in propensity-adjusted multiple logistic regression analysis (OR 0.32, 95% CI 0.12-0.82, p = 0.021) thus controlling for a wide number of covariates. Sensitivities of baseline suPAR and SCOPE score in predicting progression towards severe disease or death at day 14 were similar (83% vs 100%, p = 0.59). This real-word, retrospective cohort study confirmed the safety and the efficacy of suPAR-guided, early use of anakinra in hospitalized COVID-19 patients with respiratory failure.

Microglial IL-1RA ameliorates brain injury after ischemic stroke by inhibiting astrocytic CXCL1-mediated neutrophil recruitment and microvessel occlusion.

Acute ischemic stroke (AIS), one of the leading causes of mortality worldwide, is characterized by a rapid inflammatory cascade resulting in exacerbation of ischemic brain injury. Microglia are the first immune responders. However, the role of postischemic microglial activity in ischemic brain injury remains far from being fully understood. Here, using the transgenic mouse line CX3 CR1creER :R26iDTR to genetically ablate microglia, we showed that microglial deletion exaggerated ischemic brain injury. Associated with this worse outcome, there were increased neutrophil recruitment, microvessel blockade and blood flow stagnation in the acute phase, accompanied by transcriptional upregulation of chemokine (C-X-C motif) ligand 1 (CXCL1). Our study showed that microglial interleukin-1 receptor antagonist (IL-1RA) suppressed astrocytic CXCL1 expression induced by oxygen and glucose deprivation and inhibited neutrophil migration. Furthermore, neutralizing antibody therapy against CXCL1 or the administration of recombinant IL-1RA protein reduced brain infarct volume and improved motor coordination performance of mice after ischemic stroke. Our study suggests that microglia protect against acute ischemic brain injury by secreting IL-1RA to inhibit astrocytic CXCL1 expression, which reduces neutrophil recruitment and neutrophil-derived microvessel occlusion.

Novel Pathophysiological, Diagnostic and Therapeutic Concepts in Acute and Recurrent Pericarditis

Acute pericarditis is the most frequent pericardial disease characterized by inflammation of the pericardial layers resulting in pain, dyspnea and fatigue. Often limited to an isolated event, up to 30% of patients experience one or more recurrences. There is limited knowledge about the pathophysiology of this disease, possibly due to the limited availability of animal models. More recently, following seminal clinical trials with colchicine and interleukin-1 (IL-1) blockers and a novel murine model of acute pericarditis using zymosan A, it has become clear that the NLRP3 (NACHT, leucine-rich repeat, and pyrin domain-containing protein 3) inflammasome/IL-1β axis plays a central role in driving acute pericardial inflammation and in sustaining this process during recurrences. Diagnostic management of pericarditis has been implemented with multimodality imaging including echocardiography, cardiac computed tomography, and cardiac magnetic resonance. These imaging modalities provide essential diagnostic and pathogenetic information, and are able to characterize pericardial inflammation, allowing to refine risk stratification and personalize treatment. Recent acquisitions yield relevant implications with regard to the therapeutic management of acute and recurrent pericarditis. Non-steroidal anti-inflammatory drugs (NSAIDs) and colchicine are cornerstone therapies either for acute and recurrent pericarditis. However, the benefits of targeted agents, such as anakinra — a recombinant human IL-1 receptor antagonist — and rilonacept — an IL-1α/IL-1β trap, are being increasingly recognized. To this end, phenotyping patients with pericarditis and addressing such therapies to those presenting with auto-inflammatory features (elevated C-reactive protein, sustained pericardial and systemic inflammation, multiple recurrences) is of utmost importance to identify patients who might be more likely to benefit from NLRP3 inflammasome/IL-1β pathway blockade.

Anakinra as a potential treatment for COVID-19.

On November 8, 2022, the United States Food and Drug Administration (FDA) issued an emergency use authorization for the interleukin-1 (IL-1) inhibitor anakinra for the treatment of patients with COVID-19 pneumonia. The authorization was specifically intended for patients requiring supplemental oxygen who are at risk of progression to respiratory failure and are likely to have an elevated plasma soluble urokinase plasminogen activator receptor. Anakinra is a modified, recombinant human IL-1 receptor antagonist used to treat rheumatoid arthritis, neonatal-onset multisystem inflammatory disease and other inflammatory diseases. This manuscript examines what is known about the role of IL-1 receptor antagonism in the treatment of patients with COVID-19 and examines how anakinra may be used in the future to address the SARS-CoV-2 infection pandemic.

Detection of Inflammatory Biomarker suPAR in COVID-19 Disease With CHORUS TRIO Instrument.

Deregulation in the urokinase-type plasminogen activator receptor (uPA/uPAR) system is reported in many diseases where the immune system is activated. During SARS-CoV-2 infection, a rise in soluble uPAR (suPAR) levels has been detected and its concentration above 6 µg/L predicts worsening to severe respiratory failure 14 days earlier, with a positive predictive value of 85.9%, and was the prerequisite for a treatment with anakinra, a recombinant IL-1 receptor antagonist that blocks the activity of both IL-1α and IL-1β. To compare suPAR concentrations measured by CHORUS suPAR on CHORUS TRIO instrument of DIESSE with the commercially available suPARnostic (ViroGates) ELISA assay. A single-centre, non-pharmacological, diagnostic study was performed. A total of 522 serum samples from patients with COVID-19 were tested for suPAR. CHORUS suPAR resulted accurate and reliable, with a high grade of specificity (97.9%), accuracy (97.3%) and sensitivity (96.9%). The median concentration of suPAR, as determined with CHORUS suPAR, was 6.8 µg/L (interquartile range 4.5-9.7) in patients with moderate disease (n = 465) and 8.5 µg/L (interquartile range 5.4-10.6) in patients with severe disease. Among patients with moderate and severe disease, 60.6% and 71.9%, respectively, reached the cut-off concentration of suPAR ⩾6 µg/L, defining their illness severity and suggesting eligibility to anakinra treatment. CHORUS suPAR kit resulted as sensitive, specific, accurate and able to quantify suPAR concentrations in patients with moderate and severe COVID-19.

ImmunoSep (Personalised Immunotherapy in Sepsis) international double-blind, double-dummy, placebo-controlled randomised clinical trial: study protocol

IntroductionSepsis is a major cause of death among hospitalised patients. Accumulating evidence suggests that immune response during sepsis cascade lies within a spectrum of dysregulated host responses. On the one...

Abstract 10389: Interleukin-1 Blockade With Anakinra Restores Cardiac Contractility Reserve and Exercise Capacity in a Mouse Model of Ischemic Heart Failure

Background: Acute myocardial infarction (AMI) is associated with an intense inflammatory response promoting adverse cardiac remodeling, impaired cardiac reserve, and reduced exercise capacity, hallmarks of heart failure. Interleukin-1β (IL-1β) is the prototypical inflammatory cytokine that is increased in AMI and is sufficient to impair cardiac reserve when administered exogenously in mice. Whether blocking IL-1β signaling with recombinant IL-1 receptor antagonist, anakinra, can restore cardiac contractile reserve and improve exercise capacity in AMI is unknown. Methods: We induced ischemic heart failure due to large non-reperfused anterior AMI in mice via surgical permanent ligation of the left anterior descending artery via lateral thoracotomy in 10-week-old male CD1 mice (N=30, 32-37 g in weight) followed for 10 weeks. Anakinra was given as intraperitoneal injection of 10 mg/kg, 0.2 ml, for three consecutive days. Cardiac contractile reserve was measured assessing changes in left ventricular fractional shortening with isoproterenol challenges (N=5). A subgroup of mice that had been previously trained to run on treadmill were used to measure interval changes in exercise capacity 10 weeks after AMI and with three consecutive days of anakinra treatment (N=6). Data are presented as mean and standard error of mean. T-test for paired group analysis was used to compare values. Results: Cardiac contractile reserve was impaired at -10±5% and restored with anakinra given for three days to +49±11% (p=0.008). Exercise capacity was also significantly reduced with AMI at 191±39 m and restored to 247±46 m after anakinra treatment (p=0.03). Conclusion: Ischemic heart failure due to large non-reperfused AMI leads to a severe reduction in cardiac contractility reserve and exercise capacity that are reversed by IL-1 blockade with anakinra.