Study protocol of a phase 2, randomised, placebo-controlled, double-blind, adaptive, parallel group clinical study to evaluate the efficacy and safety of recombinant alpha-1-microglobulin in subjects at high risk for acute kidney injury following open-chest cardiac surgery (AKITA trial).

INTRODUCTION: Acute kidney injury (AKI) is a common complication after cardiac surgery (CS) and is associated with adverse short-term and long-term outcomes. Alpha-1-microglobulin (A1M) is a circulating glycoprotein with antioxidant, heme binding and mitochondrial-protective mechanisms. RMC-035 is a modified, more soluble, variant of A1M and has been proposed as a novel targeted therapeutic protein to prevent CS-associated AKI (CS-AKI). RMC-035 was considered safe and generally well tolerated when evaluated in four clinical phase 1 studies. METHODS AND ANALYSIS: This is a phase 2, randomised, double-blind, adaptive design, parallel group clinical study that evaluates RMC-035 compared with placebo in approximately 268 cardiac surgical patients at high risk for CS-AKI. RMC-035 is administered as an intravenous infusion. In total, five doses will be given. Dosing is based on presurgery estimated glomerular filtration rate (eGFR), and will be either 1.3 or 0.65 mg/kg.The primary study objective is to evaluate whether RMC-035 reduces the incidence of postoperative AKI, and key secondary objectives are to evaluate whether RMC-035 improves postoperative renal function compared with placebo. A blinded interim analysis with potential sample size reassessment is planned once 134 randomised subjects have completed dosing. An independent data monitoring committee will evaluate safety and efficacy data at prespecified intervals throughout the trial. The study is a global multicentre study at approximately 30 sites. ETHICS AND DISSEMINATION: The trial was approved by the joint ethics committee of the physician chamber Westfalen-Lippe and the University of Münster (code '2021-778 f-A') and subsequently approved by the responsible ethics committees/relevant institutional review boards for the participating sites. The study is conducted in accordance with Good Clinical Practice, the Declaration of Helsinki and other applicable regulations. Results of this study will be published in a peer-reviewed scientific journal. TRIAL REGISTRATION NUMBER: NCT05126303.

The Role of Cell Cycle Arrest Biomarkers for Predicting Acute Kidney Injury in Critically Ill COVID-19 Patients: A Multicenter, Observational Study.

OBJECTIVES: Patients with COVID-19-associated acute respiratory distress syndrome (ARDS) have a high risk for developing acute kidney injury (AKI) which is associated with an increased risk of death and persistent renal failure. Early prediction of AKI is crucial in order to implement preventive strategies. The purpose of this study was to investigate the predictive performance of tissue inhibitor of metalloproteinases 2 and insulin like growth factor binding protein 7 (TIMP-2) × (IGFBP7) in critically ill patients with COVID-19-associated ARDS. DESIGN: Multicenter, prospective, observational study. SETTING: Twelve centers across Europe and United Kingdom. PATIENTS: Patients with moderate or severe COVID-19-associated ARDS were included and serial measurements of (TIMP-2) × (IGFBP7) were performed. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The primary endpoint was the development of moderate or severe AKI according to the Kidney Disease: Improving Global Outcomes definition. Three hundred patients were available for the primary analysis, and 39 met the primary endpoint. At enrollment, urinary (TIMP-2) × (IGFBP7) had high predictive value for the primary endpoint with an area under the receiver operating characteristic curve of 0.89 (95% CI, 0.84-0.93). (TIMP-2) × (IGFBP7) was significantly higher in endpoint-positive patients at enrollment and at 12 hours. CONCLUSIONS: Urinary (TIMP-2) × (IGFBP7) predicts the occurrence of AKI in critically ill patients with COVID-19-associated ARDS.

Inhaled prostacyclin therapy in the acute respiratory distress syndrome: a randomized controlled multicenter trial.

BACKGROUND: Acute respiratory distress syndrome (ARDS) results in significant hypoxia, and ARDS is the central pathology of COVID-19. Inhaled prostacyclin has been proposed as a therapy for ARDS, but data regarding its role in this syndrome are unavailable. Therefore, we investigated whether inhaled prostacyclin would affect the oxygenation and survival of patients suffering from ARDS. METHODS: We performed a prospective randomized controlled single-blind multicenter trial across Germany. The trial was conducted from March 2019 with final follow-up on 12th of August 2021. Patients with moderate to severe ARDS were included and randomized to receive either inhaled prostacyclin (3 times/day for 5 days) or sodium chloride (Placebo). The primary outcome was the oxygenation index in the intervention and control groups on Day 5 of therapy. Secondary outcomes were mortality, secondary organ failure, disease severity and adverse events. RESULTS: Of 707 patients approached 150 patients were randomized to receive inhaled prostacyclin (n = 73) or sodium chloride (n = 77). Data from 144 patients were analyzed. The baseline PaO2/FiO2 ratio did not differ between groups. The primary analysis of the study was negative, and prostacyclin improved oxygenation by 20 mmHg more than Placebo (p = 0.17). Secondary analysis showed that the oxygenation was significantly improved in patients with ARDS who were COVID-19-positive (34 mmHg, p = 0.04). Mortality did not differ between groups. Secondary organ failure and adverse events were similar in the intervention and control groups. CONCLUSIONS: The primary result of our study was negative. Our data suggest that inhaled prostacyclin might be beneficial treatment in patients with COVID-19 induced ARDS. TRIAL REGISTRATION: The study was approved by the Institutional Review Board of the Research Ethics Committee of the University of Tübingen (899/2018AMG1) and the corresponding ethical review boards of all participating centers. The trial was also approved by the Federal Institute for Drugs and Medical Devices (BfArM, EudraCT No. 2016003168-37) and registered at clinicaltrials.gov (NCT03111212) on April 6th 2017.

Study protocol of a randomised, double-blind, placebo-controlled, two-arm parallel-group, multi-centre phase 3 pivotal trial to investigate the efficacy and safety of recombinant human alkaline phosphatase for treatment of patients with sepsis-associated acute kidney injury.

INTRODUCTION: Sepsis, the leading cause of acute kidney injury (AKI), is associated with a high morbidity and mortality. Alkaline phosphatase (ALP) is an endogenous detoxifying enzyme. A recombinant human ALP compound, ilofotase alfa, showed no safety or tolerability concerns in a phase 2 trial. Renal function improvement over 28 days was significantly greater in the ilofotase alfa group. Moreover, a significant relative reduction in 28-day all-cause mortality of >40% was observed. A follow-up trial has been designed to confirm these findings. METHODS AND ANALYSIS: This is a phase 3, global, multi-centre, randomised, double-blind, placebo-controlled, sequential design trial in which patients are randomly assigned to either placebo or 1.6 mg/kg ilofotase alfa. Randomisation is stratified by baseline modified Sequential Organ Failure Assessment (mSOFA) score and trial site. The primary objective is to confirm the survival benefit with ilofotase alfa by demonstrating a reduction in 28-day all-cause mortality in patients with sepsis-associated AKI requiring vasopressors. A maximum of 1400 patients will be enrolled at ∼120 sites in Europe, North America, Japan, Australia and New Zealand. Up to four interim analyses will take place. Based on predefined decision rules, the trial may be stopped early for futility or for effectiveness. In addition, patients with COVID-19 disease and patients with 'moderate to severe' chronic kidney disease are analysed as 2 separate cohorts of 100 patients each. An independent Data Monitoring Committee evaluates safety data at prespecified intervals throughout the trial. ETHICS AND DISSEMINATION: The trial is approved by relevant institutional review boards/independent ethics committees and is conducted in accordance with the ethical principles of the Declaration of Helsinki, guidelines of Good Clinical Practice, Code of Federal Regulations and all other applicable regulations. Results of this study will determine the potential of ilofotase alfa to reduce mortality in critically ill patients with sepsis-associated AKI and will be published in a peer-reviewed scientific journal. TRIAL REGISTRATION NUMBER: EudraCT CT Number 2019-0046265-24. US IND Number 117 605 Pre-results. CLINICALTRIALS: gov number: NCT04411472.

Angiotensin II - A Brief Review and Role in Severe SARS-COV-2 Sepsis.

The renin-angiotensin-aldosterone system (RAAS), whose major vasopressor effector is angiotensin II (ATII), has multiple activities and regulates sodium-water homeostasis and fluid and blood pressure homeostasis. RAAS plays a crucial role in cardiocirculatory shock because it counteracts hypotension and hypovolemia by activating different physiologic responses. Based on the encouraging results of the ATHOS-3 trial, the US Food and Drug Administration and the European Medicines Agency approved the use of ATII for catecholamine-resistant vasodilatory shock. More recently, ATII was used for the compassionate treatment of critically ill patients with COVID-19. Beyond its vasopressor properties, ATII was hypothesized to have antiviral activity because it induces internalization and degradation of angiotensin-converting enzyme 2 receptors used by SARS-Cov-2 to infect cells. Overall, the use of ATII in patients with COVID-19 showed promising results because its administration was associated with the achievement and maintenance of target mean arterial pressure, increased PaO2/FIO2 ratio, and decreased FIO2. The aim of this narrative review is to summarize the available knowledge on the use of ATII in patients with COVID-19.

COVID-19 does not influence functional status after ARDS therapy.

RATIONALE: Health-related quality of life after surviving acute respiratory distress syndrome has come into focus in recent years, especially during the coronavirus disease 2019 pandemic. OBJECTIVES: A total of 144 patients with acute respiratory distress syndrome caused by COVID-19 or of other origin were recruited in a randomized multicenter trial. METHODS: Clinical data during intensive care treatment and data up to 180 days after study inclusion were collected. Changes in the Sequential Organ Failure Assessment score were used to quantify disease severity. Disability was assessed using the Barthel index on days 1, 28, 90, and 180. MEASUREMENTS: Mortality rate and morbidity after 180 days were compared between patients with and without COVID-19. Independent risk factors associated with high disability were identified using a binary logistic regression. MAIN RESULTS: The SOFA score at day 5 was an independent risk factor for high disability in both groups, and score dynamic within the first 5 days significantly impacted disability in the non-COVID group. Mortality after 180 days and impairment measured by the Barthel index did not differ between patients with and without COVID-19. CONCLUSIONS: Resolution of organ dysfunction within the first 5 days significantly impacts long-term morbidity. Acute respiratory distress syndrome caused by COVID-19 was not associated with increased mortality or morbidity.

Increased prevalence of clonal hematopoiesis of indeterminate potential in hospitalized patients with COVID-19.

Clonal hematopoiesis of indeterminate potential (CHIP) leads to higher mortality, carries a cardiovascular risk and alters inflammation. All three aspects harbor overlaps with the clinical manifestation of COVID-19. This study aimed to identify the impact of CHIP on COVID-19 pathophysiology. 90 hospitalized patients were analyzed for CHIP. In addition, their disease course and outcome were evaluated. With a prevalence of 37.8%, the frequency of a CHIP-driver mutation was significantly higher than the prevalence expected based on median age (17%). CHIP increases the risk of hospitalization in the course of the disease but has no age-independent impact on the outcome within the group of hospitalized patients. Especially in younger patients (45 - 65 years), CHIP was associated with persistent lymphopenia. In older patients (> 65 years), on the other hand, CHIP-positive patients developed neutrophilia in the long run. To what extent increased values of cardiac biomarkers are caused by CHIP independent of age could not be elaborated solely based on this study. In conclusion, our results indicate an increased susceptibility to a severe course of COVID-19 requiring hospitalization associated with CHIP. Secondly, they link it to a differentially regulated cellular immune response under the pressure of SARS-CoV-2 infection. Hence, a patient's CHIP-status bears the potential to serve as biomarker for risk stratification and to early guide treatment of COVID-19 patients.

The Distinctive Activation of Toll-Like Receptor 4 in Human Samples with Sepsis.

Clinical success of Toll-Like receptor-4 (TLR-4) antagonists in sepsis therapy has thus far been lacking. As inhibition of a receptor can only be useful if the receptor is active, stratification of patients with active TLR-4 would be desirable. Our aim was to establish an assay to quantify phosphorylated TLR-4 using the proximity ligation assay (PLA). HEK293 TLR4/MD2/CD14 as well as THP-1 cells were stimulated with LPS and the activation of TLR-4 was measured using the PLA. Furthermore, peripheral blood mononuclear cells (PBMCs) from 25 sepsis patients were used to show the feasibility of this assay in clinical material. Activation of TLR-4 in these samples was compared to the PBMCs of 11 healthy individuals. We could show a transient activation of TLR-4 in both cell lines. Five min after the LPS stimulation, the signal increased 6.7-fold in the HEK293 cells and 4.3-fold in the THP-1 cells. The assay also worked well in the PBMCs of septic patients. Phosphorylation of TLR-4 at study inclusion was 2.9 times higher in septic patients compared to healthy volunteers. To conclude, we established a diagnostic assay that is able to quantify the phosphorylation of TLR-4 in cell culture and in clinical samples of sepsis patients. This makes large-scale stratification of sepsis patients for their TLR-4 activation status possible.

Platelets at the Crossroads of Pro-Inflammatory and Resolution Pathways during Inflammation.

Platelets are among the most abundant cells in the mammalian circulation. Classical platelet functions in hemostasis and wound healing have been intensively explored and are generally accepted. During the past decades, the research focus broadened towards their participation in immune-modulatory events, including pro-inflammatory and, more recently, inflammatory resolution processes. Platelets are equipped with a variety of abilities enabling active participation in immunological processes. Toll-like receptors mediate the recognition of pathogens, while the release of granule contents and microvesicles promotes direct pathogen defense and an interaction with leukocytes. Platelets communicate and physically interact with neutrophils, monocytes and a subset of lymphocytes via soluble mediators and surface adhesion receptors. This interaction promotes leukocyte recruitment, migration and extravasation, as well as the initiation of effector functions, such as the release of extracellular traps by neutrophils. Platelet-derived prostaglandin E2, C-type lectin-like receptor 2 and transforming growth factor ß modulate inflammatory resolution processes by promoting the synthesis of pro-resolving mediators while reducing pro-inflammatory ones. Furthermore, platelets promote the differentiation of CD4+ T cells in T helper and regulatory T cells, which affects macrophage polarization. These abilities make platelets key players in inflammatory diseases such as pneumonia and the acute respiratory distress syndrome, including the pandemic coronavirus disease 2019. This review focuses on recent findings in platelet-mediated immunity during acute inflammation.

Secondary Immunodeficiency Related to Kidney Disease (SIDKD)-Definition, Unmet Need, and Mechanisms.

Kidney disease is a known risk factor for poor outcomes of COVID-19 and many other serious infections. Conversely, infection is the second most common cause of death in patients with kidney disease. However, little is known about the underlying secondary immunodeficiency related to kidney disease (SIDKD). In contrast to cardiovascular disease related to kidney disease, which has triggered countless epidemiologic, clinical, and experimental research activities or interventional trials, investments in tracing, understanding, and therapeutically targeting SIDKD have been sparse. As a call for more awareness of SIDKD as an imminent unmet medical need that requires rigorous research activities at all levels, we review the epidemiology of SIDKD and the numerous aspects of the abnormal immunophenotype of patients with kidney disease. We propose a definition of SIDKD and discuss the pathogenic mechanisms of SIDKD known thus far, including more recent insights into the unexpected immunoregulatory roles of elevated levels of FGF23 and hyperuricemia and shifts in the secretome of the intestinal microbiota in kidney disease. As an ultimate goal, we should aim to develop therapeutics that can reduce mortality due to infections in patients with kidney disease by normalizing host defense to pathogens and immune responses to vaccines.

The impact of the COVID-19 pandemic on non-COVID induced sepsis survival.

BACKGROUND: The COVID-19 pandemic has taken a toll on health care systems worldwide, which has led to increased mortality of different diseases like myocardial infarction. This is most likely due to three factors. First, an increased workload per nurse ratio, a factor associated with mortality. Second, patients presenting with COVID-19-like symptoms are isolated, which also decreases survival in cases of emergency. And third, patients hesitate to see a doctor or present themselves at a hospital. To assess if this is also true for sepsis patients, we asked whether non-COVID-19 sepsis patients had an increased 30-day mortality during the COVID-19 pandemic. METHODS: This is a post hoc analysis of the SepsisDataNet.NRW study, a multicentric, prospective study that includes septic patients fulfilling the SEPSIS-3 criteria. Within this study, we compared the 30-day mortality and disease severity of patients recruited pre-pandemic (recruited from March 2018 until February 2020) with non-COVID-19 septic patients recruited during the pandemic (recruited from March 2020 till December 2020). RESULTS: Comparing septic patients recruited before the pandemic to those recruited during the pandemic, we found an increased raw 30-day mortality in sepsis-patients recruited during the pandemic (33% vs. 52%, p = 0.004). We also found a significant difference in the severity of disease at recruitment (SOFA score pre-pandemic: 8 (5 - 11) vs. pandemic: 10 (8 - 13); p < 0.001). When adjusted for this, the 30-day mortality rates were not significantly different between the two groups (52% vs. 52% pre-pandemic and pandemic, p = 0.798). CONCLUSIONS: This led us to believe that the higher mortality of non-COVID19 sepsis patients during the pandemic might be attributed to a more severe septic disease at the time of recruitment. We note that patients may experience a delayed admission, as indicated by elevated SOFA scores. This could explain the higher mortality during the pandemic and we found no evidence for a diminished quality of care for critically ill sepsis patients in German intensive care units.

Prediction of cardiac surgery associated - acute kidney injury (CSA-AKI) by healthcare professionals and urine cell cycle arrest AKI biomarkers [TIMP-2]*[IGFBP7]: A single center prospective study (the PREDICTAKI trial).

PURPOSE: Cardiac surgery associated acute kidney injury (CSA-AKI) is a contributor to adverse outcomes. Preventive measures reduce AKI incidence in high risk patients, identified by biomarkers [TIMP-2]*[IGFBP7] (Nephrocheck®). This study investigate clinical AKI risk assessment by healthcare professionals and the added value of the biomarker result. MATERIALS AND METHODS: Adult patients were prospectively included. Healthcare professionals predicted CSA-AKI, with and without biomarker result knowledge. Predicted outcomes were AKI based on creatinine, AKI stage 3 on urine output, anuria and use of kidney replacement therapy (KRT). RESULTS: One-hundred patients were included. Consultant and ICU residents were best in AKI prediction, respectively AUROC 0.769 (95% CI, 0.672-0.850) and 0.702 (95% CI, 0.599-0.791). AUROC of NephroCheck® was 0.541 (95% CI, 0.438-0.642). AKI 3 occurred in only 4 patients; there was no anuria or use of KRT. ICU nurses and ICU residents had an AUROC for prediction of AKI 3 of respectively 0.867 (95% CI, 0.780-0.929) and 0.809 (95% CI, 0.716-0.883); for NephroCheck® this was 0.838 (95% CI, 0.750-0.904). CONCLUSIONS: Healthcare professionals performed poor or fair in predicting CSA-AKI and knowledge of Nephrocheck® result did not improved prediction. No conclusions could be made for prediction of severe AKI, due to limited number of events.

Neutrophils in acute inflammation: current concepts and translational implications.

Modulation of neutrophil recruitment and function is crucial for targeting inflammatory cells to sites of infection to combat invading pathogens while, at the same time, limiting host tissue injury or autoimmunity. The underlying mechanisms regulating recruitment of neutrophils, 1 of the most abundant inflammatory cells, have gained increasing interest over the years. The previously described classical recruitment cascade of leukocytes has been extended to include capturing, rolling, adhesion, crawling, and transmigration, as well as a reverse-transmigration step that is crucial for balancing immune defense and control of remote organ endothelial leakage. Current developments in the field emphasize the importance of cellular interplay, tissue environmental cues, circadian rhythmicity, detection of neutrophil phenotypes, differential chemokine sensing, and contribution of distinct signaling components to receptor activation and integrin conformations. The use of therapeutics modulating neutrophil activation responses, as well as mutations causing dysfunctional neutrophil receptors and impaired signaling cascades, have been defined in translational animal models. Human correlates of such mutations result in increased susceptibility to infections or organ damage. This review focuses on current advances in the understanding of the regulation of neutrophil recruitment and functionality and translational implications of current discoveries in the field with a focus on acute inflammation and sepsis.

A Fragile Balance: Does Neutrophil Extracellular Trap Formation Drive Pulmonary Disease Progression?

Neutrophils act as the first line of defense during infection and inflammation. Once activated, they are able to fulfil numerous tasks to fight inflammatory insults while keeping a balanced immune response. Besides well-known functions, such as phagocytosis and degranulation, neutrophils are also able to release "neutrophil extracellular traps" (NETs). In response to most stimuli, the neutrophils release decondensed chromatin in a NADPH oxidase-dependent manner decorated with histones and granule proteins, such as neutrophil elastase, myeloperoxidase, and cathelicidins. Although primarily supposed to prevent microbial dissemination and fight infections, there is increasing evidence that an overwhelming NET response correlates with poor outcome in many diseases. Lung-related diseases especially, such as bacterial pneumonia, cystic fibrosis, chronic obstructive pulmonary disease, aspergillosis, influenza, and COVID-19, are often affected by massive NET formation. Highly vascularized areas as in the lung are susceptible to immunothrombotic events promoted by chromatin fibers. Keeping this fragile equilibrium seems to be the key for an appropriate immune response. Therapies targeting dysregulated NET formation might positively influence many disease progressions. This review highlights recent findings on the pathophysiological influence of NET formation in different bacterial, viral, and non-infectious lung diseases and summarizes medical treatment strategies.

Patients with COVID-19: in the dark-NETs of neutrophils.

SARS-CoV-2 infection poses a major threat to the lungs and multiple other organs, occasionally causing death. Until effective vaccines are developed to curb the pandemic, it is paramount to define the mechanisms and develop protective therapies to prevent organ dysfunction in patients with COVID-19. Individuals that develop severe manifestations have signs of dysregulated innate and adaptive immune responses. Emerging evidence implicates neutrophils and the disbalance between neutrophil extracellular trap (NET) formation and degradation plays a central role in the pathophysiology of inflammation, coagulopathy, organ damage, and immunothrombosis that characterize severe cases of COVID-19. Here, we discuss the evidence supporting a role for NETs in COVID-19 manifestations and present putative mechanisms, by which NETs promote tissue injury and immunothrombosis. We present therapeutic strategies, which have been successful in the treatment of immunο-inflammatory disorders and which target dysregulated NET formation or degradation, as potential approaches that may benefit patients with severe COVID-19.

Leukocyte trafficking to the lungs and beyond: lessons from influenza for COVID-19.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19). Understanding of the fundamental processes underlying the versatile clinical manifestations of COVID-19 is incomplete without comprehension of how different immune cells are recruited to various compartments of virus-infected lungs, and how this recruitment differs among individuals with different levels of disease severity. As in other respiratory infections, leukocyte recruitment to the respiratory system in people with COVID-19 is orchestrated by specific leukocyte trafficking molecules, and when uncontrolled and excessive it results in various pathological complications, both in the lungs and in other organs. In the absence of experimental data from physiologically relevant animal models, our knowledge of the trafficking signals displayed by distinct vascular beds and epithelial cell layers in response to infection by SARS-CoV-2 is still incomplete. However, SARS-CoV-2 and influenza virus elicit partially conserved inflammatory responses in the different respiratory epithelial cells encountered early in infection and may trigger partially overlapping combinations of trafficking signals in nearby blood vessels. Here, we review the molecular signals orchestrating leukocyte trafficking to airway and lung compartments during primary pneumotropic influenza virus infections and discuss potential similarities to distinct courses of primary SARS-CoV-2 infections. We also discuss how an imbalance in vascular activation by leukocytes outside the airways and lungs may contribute to extrapulmonary inflammatory complications in subsets of patients with COVID-19. These multiple molecular pathways are potential targets for therapeutic interventions in patients with severe COVID-19.

Publisher Correction: COVID-19-associated acute kidney injury: consensus report of the 25th Acute Disease Quality Initiative (ADQI) Workgroup.

An amendment to this paper has been published and can be accessed via a link at the top of the paper.