The effect of intravenous interferon-beta-1a (FP-1201) on lung CD73 expression and on acute respiratory distress syndrome mortality: an open-label study

Inhibiting Eph/ephrin signaling reduces vascular leak and endothelial cell dysfunction in mice with sepsis

Sepsis is a life-threatening disease caused by a dysregulated host response to infection, resulting in 11 million deaths globally each year. Vascular endothelial cell dysfunction results in the loss of endothelial barrier integrity, which contributes to sepsis-induced multiple organ failure and mortality. Erythropoietin-producing hepatocellular carcinoma (Eph) receptors and their ephrin ligands play a key role in vascular endothelial barrier disruption but are currently not a therapeutic target in sepsis. Using a cecal ligation and puncture (CLP) mouse model of sepsis, we showed that prophylactic or therapeutic treatment of mice with EphA4-Fc, a decoy receptor and pan-ephrin inhibitor, resulted in improved survival and a reduction in vascular leak, lung injury, and endothelial cell dysfunction. EphA2-/- mice also exhibited reduced mortality and pathology after CLP compared with wild-type mice. Proteomics of plasma samples from mice with sepsis after CLP revealed dysregulation of a number of Eph/ephrins, including EphA2/ephrin A1. Administration of EphA4-Fc to cultured human endothelial cells pretreated with TNF-α or ephrin-A1 prevented loss of endothelial junction proteins, specifically VE-cadherin, with maintenance of endothelial barrier integrity. In children admitted to hospital with fever and suspected infection, we observed that changes in EphA2/ephrin A1 in serum samples correlated with endothelial and organ dysfunction. Targeting Eph/ephrin signaling may be a potential therapeutic strategy to reduce sepsis-induced endothelial dysfunction and mortality.

The endothelium: gatekeeper to lung ischemia-reperfusion injury

The success of lung transplantation is limited by the high rate of primary graft dysfunction due to ischemia-reperfusion injury (IRI). Lung IRI is characterized by a robust inflammatory response, lung dysfunction, endothelial barrier disruption, oxidative stress, vascular permeability, edema, and neutrophil infiltration. These events are dependent on the health of the endothelium, which is a primary target of IRI that results in pulmonary endothelial barrier dysfunction. Over the past 10 years, research has focused more on the endothelium, which is beginning to unravel the multi-factorial pathogenesis and immunologic mechanisms underlying IRI. Many important proteins, receptors, and signaling pathways that are involved in the pathogenesis of endothelial dysfunction after IR are starting to be identified and targeted as prospective therapies for lung IRI. In this review, we highlight the more significant mediators of IRI-induced endothelial dysfunction discovered over the past decade including the extracellular glycocalyx, endothelial ion channels, purinergic receptors, kinases, and integrins. While there are no definitive clinical therapies currently available to prevent lung IRI, we will discuss potential clinical strategies for targeting the endothelium for the treatment or prevention of IRI. The accruing evidence on the essential role the endothelium plays in lung IRI suggests that promising endothelial-directed treatments may be approaching the clinic soon. The application of therapies targeting the pulmonary endothelium may help to halt this rapid and potentially fatal injury.

Adjunctive Therapies in Acute Respiratory Distress Syndrome

Despite significant advances in understanding acute respiratory distress syndrome (ARDS), mortality rates remain high. The appropriate use of adjunctive therapies can improve outcomes, particularly for patients with moderate to severe hypoxia. In this review, the authors discuss the evidence basis behind prone positioning, recruitment maneuvers, neuromuscular blocking agents, corticosteroids, pulmonary vasodilators, and extracorporeal membrane oxygenation and considerations for their use in individual patients and specific clinical scenarios. Because the heterogeneity of ARDS poses challenges in finding universally effective treatments, an individualized approach and continued research efforts are crucial for optimizing the utilization of adjunctive therapies and improving patient outcomes.

Investigational pharmacological agents for the treatment of ARDS

INTRODUCTION

Acute Respiratory Distress Syndrome (ARDS) is a heterogeneous form of lung injury with severe hypoxemia and bilateral infiltrates after an inciting event that results in diffuse lung inflammation with a high mortality rate. While research in COVID-related ARDS has resulted in several pharmacotherapeutic agents that have undergone successful investigation, non-COVID ARDS studies have not resulted in many widely accepted pharmacotherapeutic agents despite exhaustive research.

AREAS COVERED

The aim of this review is to discuss adjuvant pharmacotherapies targeting non-COVID Acute Lung Injury (ALI)/ARDS and novel therapeutics in COVID associated ALI/ARDS. In ARDS, variable data may support selective use of neuromuscular blocking agents, corticosteroids and neutrophil elastase inhibitors, but are not yet universally used. COVID-ALI/ARDS has data supporting the use of IL-6 monoclonal antibodies, corticosteroids, and JAK inhibitor therapy.

EXPERT OPINION

Although ALI/ARDS modifying pharmacological agents have been identified in COVID-related disease, the data in non-COVID ALI/ARDS has been less compelling. The increased use of more specific molecular phenotyping based on physiologic parameters and biomarkers, will ensure equipoise between groups, and will likely allow more precision in confirming pharmacological agent efficacy in future studies.

Immunomodulatory approaches in managing lung inflammation in COVID-19: A double-edge sword

INTRODUCTION

The novel coronavirus infectious disease 2019 (COVID-19) which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has emerged as a gigantic problem. The lung is the major target organ of SARS-CoV-2 and some of its variants like Delta and Omicron variant adapted in such a way that these variants can significantly damage this vital organ of the body. These variants raised a few eyebrows as the outbreaks have been seen in the vaccinated population. Patients develop severe respiratory illnesses which eventually prove fatal unless treated early.

MAIN BODY

Studies have shown that SARS-CoV-2 causes the release of pro-inflammatory cytokines such as interleukin (IL)-6, IL-1β and tumor necrosis factor (TNF)-α which are mediators of lung inflammation, lung damage, fever, and fibrosis. Additionally, various chemokines have been found to play an important role in the disease progression. A plethora of pro-inflammatory cytokines "cytokine storm" has been observed in severe cases of SARS-CoV-2 infection leading to acute respiratory distress syndrome (ARDS) and pneumonia that may prove fatal. To counteract cytokine storm-inducing lung inflammation, several promising immunomodulatory approaches are being investigated in numerous clinical trials. However, the benefits of using these strategies should outweigh the risks involved as the use of certain immunosuppressive approaches might lead the host susceptible to secondary bacterial infections.

CONCLUSION

The present review discusses promising immunomodulatory approaches to manage lung inflammation in COVID-19 cases which may serve as potential therapeutic options in the future and may prove lifesaving.

Anti-inflammatory therapies for acute respiratory distress syndrome

INTRODUCTION

Treatments for the acute respiratory distress syndrome (ARDS) are mainly supportive, and ventilatory management represents a key approach in these patients. Despite progress in pharmacotherapy, anti-inflammatory strategies for the treatment of ARDS have shown controversial results. Positive outcomes with pharmacologic and nonpharmacologic treatments have been found in two different biological subphenotypes of ARDS, suggesting that, with a personalized medicine approach, pharmacotherapy for ARDS can be effective.

AREAS COVERED

This article reviews the literature concerning anti-inflammatory therapies for ARDS, focusing on pharmacological and stem-cell therapies, including extracellular vesicles.

EXPERT OPINION

Despite advances, ARDS treatments remain primarily supportive. Ventilatory and fluid management are important strategies in these patients that have demonstrated significant impacts on outcome. Anti-inflammatory drugs have shown some benefits, primarily in preclinical research and in specific clinical scenarios, but no recommendations are available from guidelines to support their use in patients with ARDS, except in particular settings such as different subphenotypes, specific etiologies, or clinical trials. Personalized medicine seems promising insofar as it may identify specific subgroups of patients with ARDS who may benefit from anti-inflammatory treatment. However, additional efforts are needed to move subphenotype characterization from bench to bedside.

Polymorphism in interferon alpha/beta receptor contributes to glucocorticoid response and outcome of ARDS and COVID-19

BACKGROUND

The use of glucocorticoids has given contradictory results for treating acute respiratory distress syndrome (ARDS). The use of intravenous Interferon beta (IFN β) for the treatment of ARDS was recently tested in a phase III ARDS trial (INTEREST), in which more than half of the patients simultaneously received glucocorticoids. Trial results showed deleterious effects of glucocorticoids when administered together with IFN β, and therefore, we aimed at finding the reason behind this.

METHODS

We first sequenced the genes encoding the IFN α/β receptor of the patients, who participated in the INTEREST study (ClinicalTrials.gov Identifier:  NCT02622724 , November 24, 2015) in which the patients were randomized to receive an intravenous injection of IFN β-1a (144 patients) or placebo (152 patients). Genetic background was analyzed against clinical outcome, concomitant medication, and pro-inflammatory cytokine levels. Thereafter, we tested the influence of the genetic background on IFN α/β receptor expression in lung organ cultures and whether, it has any effect on transcription factors STAT1 and STAT2 involved in IFN signaling.

RESULTS

We found a novel disease association of a SNP rs9984273, which is situated in the interferon α/β receptor subunit 2 (IFNAR2) gene in an area corresponding to a binding motif of the glucocorticoid receptor (GR). The minor allele of SNP rs9984273 associates with higher IFNAR expression, more rapid decrease of IFN γ and interleukin-6 (IL-6) levels and better outcome in IFN β treated patients with ARDS, while the major allele associates with a poor outcome especially under concomitant IFN β and glucocorticoid treatment. Moreover, the minor allele of rs9984273 associates with a less severe form of coronavirus diseases (COVID-19) according to the COVID-19 Host Genetics Initiative database.

CONCLUSIONS

The distribution of this SNP within clinical study arms may explain the contradictory results of multiple ARDS studies and outcomes in COVID-19 concerning type I IFN signaling and glucocorticoids.

CD73: Friend or Foe in Lung Injury

Ecto-5′-nucleotidase (CD73) plays a strategic role in calibrating the magnitude and chemical nature of purinergic signals that are delivered to immune cells. Its primary function is to convert extracellular ATP to adenosine in concert with ectonucleoside triphosphate diphosphohydrolase-1 (CD39) in normal tissues to limit an excessive immune response in many pathophysiological events, such as lung injury induced by a variety of contributing factors. Multiple lines of evidence suggest that the location of CD73, in proximity to adenosine receptor subtypes, indirectly determines its positive or negative effect in a variety of organs and tissues and that its action is affected by the transfer of nucleoside to subtype-specific adenosine receptors. Nonetheless, the bidirectional nature of CD73 as an emerging immune checkpoint in the pathogenesis of lung injury is still unknown. In this review, we explore the relationship between CD73 and the onset and progression of lung injury, highlighting the potential value of this molecule as a drug target for the treatment of pulmonary disease.

Challenges in ARDS Definition, Management, and Identification of Effective Personalized Therapies

Over the last decade, the management of acute respiratory distress syndrome (ARDS) has made considerable progress both regarding supportive and pharmacologic therapies. Lung protective mechanical ventilation is the cornerstone of ARDS management. Current recommendations on mechanical ventilation in ARDS include the use of low tidal volume (V_T) 4-6 mL/kg of predicted body weight, plateau pressure (P_PLAT) < 30 cmH₂O, and driving pressure (∆P) < 14 cmH₂O. Moreover, positive end-expiratory pressure should be individualized. Recently, variables such as mechanical power and transpulmonary pressure seem promising for limiting ventilator-induced lung injury and optimizing ventilator settings. Rescue therapies such as recruitment maneuvers, vasodilators, prone positioning, extracorporeal membrane oxygenation, and extracorporeal carbon dioxide removal have been considered for patients with severe ARDS. Regarding pharmacotherapies, despite more than 50 years of research, no effective treatment has yet been found. However, the identification of ARDS sub-phenotypes has revealed that some pharmacologic therapies that have failed to provide benefits when considering all patients with ARDS can show beneficial effects when these patients were stratified into specific sub-populations; for example, those with hyperinflammation/hypoinflammation. The aim of this narrative review is to provide an overview on current advances in the management of ARDS from mechanical ventilation to pharmacological treatments, including personalized therapy.

Decreased circulating CD73 and adenosine deaminase are associated with disease severity in hospitalized patients with COVID-19

OBJECTIVE

SARS-CoV-2 infection has been shown to result in increased circulating levels of adenosine triphosphate and adenosine diphosphate and decreased levels of adenosine, which has important anti-inflammatory activity. The goal of this pilot project was to assess the levels of soluble CD73 and soluble Adenosine Deaminase (ADA) in hospitalized patients with COVID-19 and determine if levels of these molecules are associated with disease severity.

METHODS

Plasma from 28 PCR-confirmed hospitalized COVID-19 patients who had varied disease severity based on WHO classification (6 mild/moderate, 10 severe, 12 critical) had concentrations of both soluble CD73 and ADA determined by ELISA. These concentrations were compared to healthy control plasma that is commercially available and was biobanked prior to the start of the pandemic. Additionally, outcomes such as WHO ordinal scale for disease severity, ICU admission, needed for invasive ventilation, hospital length of stay, and development of thrombosis during admission were used as markers of disease severity.

RESULTS

Our results show that both CD73 and ADA are decreased during SARS-CoV-2 infection. The level of circulating CD73 is directly correlated to the severity of the disease defined by the need for ICU admission, invasive ventilation, and hospital length of stay. Low level of CD73 is also associated with clinical thrombosis, a severe complication of SARS-CoV-2 infection.

CONCLUSION

Our study indicates that adenosine metabolism is down-regulated in patients with COVID-19 and associated with severe infection. Further large-scale studies are warranted to investigate the role of the adenosinergic anti-inflammatory CD73/ADA axis in protection against COVID-19.

Immune Modulation in Sepsis, ARDS, and Covid-19 - The Road Traveled and the Road Ahead

Immune Modulation in Sepsis, ARDS, and Covid-19Leligdowicz et al. consider the history and future of immunomodulating therapies in sepsis and ARDS, including ARDS due to Covid-19, and remark on the larger challenge of clinical research on therapies for syndromes with profound clinical and biologic heterogeneity.

Pharmacologic therapies of ARDS: From natural herb to nanomedicine

Acute respiratory distress syndrome (ARDS) is a common critical illness in respiratory care units with a huge public health burden. Despite tremendous advances in the prevention and treatment of ARDS, it remains the main cause of intensive care unit (ICU) management, and the mortality rate of ARDS remains unacceptably high. The poor performance of ARDS is closely related to its heterogeneous clinical syndrome caused by complicated pathophysiology. Based on the different pathophysiology phases, drugs, protective mechanical ventilation, conservative fluid therapy, and other treatment have been developed to serve as the ARDS therapeutic methods. In recent years, there has been a rapid development in nanomedicine, in which nanoparticles as drug delivery vehicles have been extensively studied in the treatment of ARDS. This study provides an overview of pharmacologic therapies for ARDS, including conventional drugs, natural medicine therapy, and nanomedicine. Particularly, we discuss the unique mechanism and strength of nanomedicine which may provide great promises in treating ARDS in the future.

Inhibition of KLF6 reduces the inflammation and apoptosis of type II alveolar epithelial cells in acute lung injury

BACKGROUND

The development of acute lung injury (ALI) into a severe stage leads to acute respiratory distress syndrome (ARDS). The morbidity and mortality of ALI and ARDS are very high. Objective: This study is aimed to explore the effect of Krüppel-like factor 6 (KLF6) on lipopolysaccharide (LPS)-induced type II alveolar epithelial cells in ALI by interacting with cysteine-rich angiogenic inducer 61 (CYR61).

MATERIAL AND METHODS

ALI mice model and LPS-induced type II alveolar epithelial cells were conducted to simulate ALI in vivo and in vitro. The messenger RNA (mRNA) and protein expression of KLF6 in lung tissues were detected by reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and Western blot analysis. Pathological changes in lung tissues were observed by hematoxylin and eosin (H&E) staining. The viability and KLF6 expression of A549 cells treated with different concentrations of LPS were detected by cell counting kit-8 (CCK-8) assay, RT-qPCR, and Western blot analysis. After indicated treatment, the viability and apoptosis of A549 cells were analyzed by CCK-8 and TUNEL assays, and the inflammation factors of A549 cells were detected by Enzyme-linked-immunosorbent serologic assay, RT-qPCR, and Western blot analysis. The combination of KLF6 and CYR61 was determined by chromatin immunoprecipitation (ChIP)-PCR and dual-luciferase reporter assay.

RESULTS

KLF6 expression was increased in lung tissues of ALI mice and LPS-induced A549 cells. Interference with KLF6 improved the viability, reduced the inflammatory damage, and promoted the apoptosis of LPS-induced A549 cells. In addition, KLF6 could bind to CYR61. Interference with KLF6 could decrease CYR61 expression in LPS-induced A549 cells. LPS also enhanced the TLR4/MYD88 signaling pathway, which was reversed by KLF6 interference. The above phenomena in LPS-induced A549 cells transfected with Si-KLF6 could be reversed by overexpression of CYR61.

CONCLUSION

Inhibition of KLF6 promoted the viability and reduced the inflammation and apoptosis of LPS-induced A549 cells, which was reversed by CYR61.

Treatment for acute respiratory distress syndrome in adults: A narrative review of phase 2 and 3 trials

INTRODUCTION

Ventilatory management and general supportive care of acute respiratory distress syndrome (ARDS) in the adult population have led to significant clinical improvements, but morbidity and mortality remain high. Pharmacologic strategies acting on the coagulation cascade, inflammation, oxidative stress, and endothelial cell injury have been targeted in the last decade for patients with ARDS, but only a few of these have shown potential benefits with a meaningful clinical response and improved patient outcomes. The lack of availability of specific pharmacologic treatments for ARDS can be attributed to its complex pathophysiology, different risk factors, huge heterogeneity, and difficult classification into specific biological phenotypes and genotypes.

AREAS COVERED

In this narrative review, we briefly discuss the relevance and current advances in pharmacologic treatments for ARDS in adults and the need for the development of new pharmacological strategies.

EXPERT OPINION

Identification of ARDS phenotypes, risk factors, heterogeneity, and pathophysiology may help to design clinical trials personalized according to ARDS-specific features, thus hopefully decreasing the rate of failed clinical pharmacologic trials. This concept is still under clinical investigation and needs further development.

Induction of CD73 prevents death after emergency open aortic surgery for a ruptured abdominal aortic aneurysm: a randomized, double-blind, placebo-controlled study

Mortality remains high after emergency open surgery for a ruptured abdominal aortic aneurysm (RAAA). The aim of the present study was to assess, if intravenous (IV) Interferon (IFN) beta-1a improve survival after surgery by up-regulating Cluster of differentiation (CD73). This is a multi-center phase II double-blind, 2:1 randomized, parallel group comparison of the efficacy and safety of IV IFN beta-1a vs. placebo for the prevention of death after open surgery for an infra-renal RAAA. All study patients presented a confirmed infra-renal RAAA, survived the primary emergency surgery and were treated with IFN beta-1a (10 μg) or matching placebo for 6 days after surgery. Major exclusion criteria included fatal hemorrhagic shock, chronic renal replacement therapy, diagnosed liver cirrhosis, severe congestive heart failure, advanced malignant disease, primary attempt of endovascular aortic repair (EVAR), and per-operative suprarenal clamping over 30 min. Main outcome measure was all-cause mortality at day 30 (D30) from initial emergency aortic reconstruction. The study was pre-maturely stopped due to a reported drug-drug interaction and was left under-powered. Out of 40 randomized patients 38 were included in the outcome analyses (27 IFN beta-1a and 11 placebo). There was no statistically significant difference between treatment groups at baseline except more open-abdomen and intestinal ischemia was present in the IFN beta-1a arm. D30 all-cause mortality was 22.2% (6/27) in the IFN beta-1a arm and 18.2% (2/11) in the placebo arm (OR 1.30; 95% CI 0.21-8.19). The most common adverse event relating to the IFN beta-1a was pyrexia (20.7% in the IFN beta-1a arm vs. 9.1% in the placebo arm). Patients with high level of serum CD73 associated with survival (P = 0.001) whereas the use of glucocorticoids and the presence of IFN beta-1a neutralizing antibodies associated with a poor CD73 response and survival. The initial aim of the trial, if postoperative INF beta-1a treatment results on better RAAA survival, could not be demonstrated. Nonetheless the anticipated target mechanism up-regulation of CD73 was associated with 100% survival. According to present results the INF beta-1a induced up-regulation of serum CD73 was blocked with both use of glucocorticoids and serum IFN beta-1a neutralizing antibodies. The study was pre-maturely stopped due to interim analysis after a study concerning the use if IV IFN beta-1a in ARDS suggested that the concomitant use of glucocorticoids and IFN beta-1a block the CD73 induction. Trial registration: ClinicalTrials.gov NCT03119701. Registered 19/04/2017 (retrospectively registered).

Unsuccessful and Successful Clinical Trials in Acute Respiratory Distress Syndrome: Addressing Physiology-Based Gaps

The acute respiratory distress syndrome (ARDS) is a severe form of acute hypoxemic respiratory failure caused by an insult to the alveolar-capillary membrane, resulting in a marked reduction of aerated alveoli, increased vascular permeability and subsequent interstitial and alveolar pulmonary edema, reduced lung compliance, increase of physiological dead space, and hypoxemia. Most ARDS patients improve their systemic oxygenation, as assessed by the ratio between arterial partial pressure of oxygen and inspired oxygen fraction, with conventional intensive care and the application of moderate-to-high levels of positive end-expiratory pressure. However, in some patients hypoxemia persisted because the lungs are markedly injured, remaining unresponsive to increasing the inspiratory fraction of oxygen and positive end-expiratory pressure. For decades, mechanical ventilation was the only standard support technique to provide acceptable oxygenation and carbon dioxide removal. Mechanical ventilation provides time for the specific therapy to reverse the disease-causing lung injury and for the recovery of the respiratory function. The adverse effects of mechanical ventilation are direct consequences of the changes in pulmonary airway pressures and intrathoracic volume changes induced by the repetitive mechanical cycles in a diseased lung. In this article, we review 14 major successful and unsuccessful randomized controlled trials conducted in patients with ARDS on a series of techniques to improve oxygenation and ventilation published since 2010. Those trials tested the effects of adjunctive therapies (neuromuscular blocking agents, prone positioning), methods for selecting the optimum positive end-expiratory pressure (after recruitment maneuvers, or guided by esophageal pressure), high-frequency oscillatory ventilation, extracorporeal oxygenation, and pharmacologic immune modulators of the pulmonary and systemic inflammatory responses in patients affected by ARDS. We will briefly comment physiology-based gaps of negative trials and highlight the possible needs to address in future clinical trials in ARDS.

Study of the effects of interferon β-1a on hospitalized patients with COVID-19: SBMU Taskforce on the COVIFERON study

Interferons are an essential part of the innate immune system and have antiviral and immunomodulatory functions. We studied the effects of interferon β-1a on the outcomes of severe cases of coronavirus disease 2019 (COVID-19). This retrospective study was conducted on hospitalized COVID-19 patients in Loghman-Hakim hospital from February 20, 2020 to April 20, 2020, Tehran, Iran. Patients were selected from two groups, the first group received interferon β-1a in addition to the standard treatment regimen, and the second group received standard care. The clinical progression of two groups during their hospital admission was compared. We studied a total number of 395 hospitalized COVID-19 patients. Out of this number, 111 patients (33.5%) died (31.3% of the interferon β-1a group and 34.1% of the control group). The mortality rate indicated no statistically significant difference between groups (p-value = 0.348), however for patients who were hospitalized for more than a week, the rate of mortality was lower in the interferon β-1a group (p-value = 0.014). The median hospital stay was statistically longer for patients treated by interferon β-1a (p-value < 0.001). The results of this study showed that interferon β-1a can improve the outcomes of hospitalized patients with severe COVID-19, but more adequately-powered randomized controlled trials should be conducted.

Endothelial dysfunction: a therapeutic target in bacterial sepsis?

INTRODUCTION

Endothelial cells maintain vascular integrity, tone, and patency and have important roles in hemostasis and inflammatory responses. Although some degree of endothelial dysfunction with increased vascular permeability may be necessary to control local infection, excessive dysfunction plays a central role in the pathogenesis of sepsis-related organ dysfunction and failure as it results in dysregulated inflammation, vascular leakage, and abnormal coagulation. The vascular endothelium has thus been proposed as a potential target for therapeutic intervention in patients with sepsis.

AREAS COVERED

Different mechanisms underlying sepsis-related dysfunction of the vascular endothelium are discussed, including glycocalyx shedding, nitrosative stress, and coagulation factors. Potential therapeutic implications of each mechanism are mentioned.

EXPERT OPINION

Multiple targets to protect or restore endothelial function have been suggested, but endothelium-driven treatments remain a future potential at present. As some endothelial dysfunction and permeability may be necessary to remove infection and repair damaged tissue, targeting the endothelium may be a particular challenge. Ideally, therapies should be guided by biomarkers related to that specific pathway to ensure they are given only to patients most likely to respond. This enrichment based on biological plausibility and theragnostics will increase the likelihood of a beneficial response in individual patients and enable more personalized treatment.

Potential therapeutics in pediatric acute respiratory distress syndrome: what does the immune system have to offer? A narrative review

Since first described, acute respiratory distress syndrome (ARDS) has been understood to be an inflammatory disease with a dysregulated hyperinflammatory response. While fewer investigations have studied these phenomena in pediatric ARDS (PARDS), similar pathways are believed to be involved. Significant attention has been paid to the innate immune system, particularly neutrophils and neutrophil-related signaling, more recent studies have provided additional nuance regarding the role of upstream damage-associated molecular patterns (DAMPs) and subsequent neutrophil-mediated inflammation, lung permeability, and alveolar epithelial damage. For example, neutrophil extracellular traps (NETs) and inflammasome signaling have been identified as critical mediators existing at the junction of DAMPs and downstream inflammation. We demonstrate how the conclusions obtained from pre-clinical studies of lung injury are highly dependent upon the model chosen, and how this can lead us astray when developing therapies. More recently the adaptive immune system, specifically select T cell subpopulations, have also been implicated in ARDS. This raises the possibility of antigen-specific immunomodulation as a potential therapeutic avenue in ARDS. Finally, we briefly review randomized controlled trials attempting to manipulate the immune dysregulation in ARDS, including pleiotropic immunomodulators like corticosteroids and interferon-β, and what these studies can teach us about the design of novel therapeutics and the design of future trials.

Potential Prophylactic Treatments for COVID-19

The World Health Organization declared the SARS-CoV-2 outbreak a Public Health Emergency of International Concern at the end of January 2020 and a pandemic two months later. The virus primarily spreads between humans via respiratory droplets, and is the causative agent of Coronavirus Disease 2019 (COVID-19), which can vary in severity, from asymptomatic or mild disease (the vast majority of the cases) to respiratory failure, multi-organ failure, and death. Recently, several vaccines were approved for emergency use against SARS-CoV-2. However, their worldwide availability is acutely limited, and therefore, SARS-CoV-2 is still expected to cause significant morbidity and mortality in the upcoming year. Hence, additional countermeasures are needed, particularly pharmaceutical drugs that are widely accessible, safe, scalable, and affordable. In this comprehensive review, we target the prophylactic arena, focusing on small-molecule candidates. In order to consolidate a potential list of such medications, which were categorized as either antivirals, repurposed drugs, or miscellaneous, a thorough screening for relevant clinical trials was conducted. A brief molecular and/or clinical background is provided for each potential drug, rationalizing its prophylactic use as an antiviral or inflammatory modulator. Drug safety profiles are discussed, and current medical indications and research status regarding their relevance to COVID-19 are shortly reviewed. In the near future, a significant body of information regarding the effectiveness of drugs being clinically studied for COVID-19 is expected to accumulate, in addition to information regarding the efficacy of prophylactic treatments.

SARS CoV-2: Progression and treatment protocols - An overview

COVID-19 pandemic is a global health crisis which has affected citizens of all nations. With more than a million death cases, this outbreak has already had a significant impact on the physical and mental wellbeing of mankind. Considerable amount of research is going on worldwide to find out effective drugs against the virus. Chloroquine phosphate, an antimalarial drug is currently used for the treatment. Studies on the harmful effects of chloroquine is in progress. India is rich in traditional medical practicing such as Ayurveda, Siddha, Unani etc. Ministry of AYUSH is trying to implement an interdisciplinary treatment encompassing all traditional methodologies. It is proven that Ashwagandha rasayana (Withania sominefera L.Dunal) has better functions than hydroxychloroquine. The ayurvedic formulations such as Sudarshan Ghanvati and Sanshamanivati are also used. The combination of hydroxychloroquine (HCQ) and azithromycin is found to cure COVID-19 more effectively. Use of Tocilizumab is found to cure the respiratory disorders associated with COVID. Favilavir turns out to be yet another effective drug. The alternative medical system has effective prophylaxis and is considered better for the treatment of COVID-19. Ayurveda and yoga improve immunity thus maintaining good health. This review throws light on the mode of progression of the virus along with the various treatment protocols adopted to fight COVID-19.

Pharmacological mechanism of immunomodulatory agents for the treatment of severe cases of COVID-19 infection

OBJECTIVE

Coronavirus disease 2019 (COVID-19) is a world-wide pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To date, treatment of severe COVID-19 is far from clear. Therefore, it is urgent to develop an effective option for the treatment of patients with COVID-19. Most patients with severe COVID-19 exhibit markedly increased serum levels of pro-inflammatory cytokines, including interferon (IFN)-α, IFN-γ, and interleukin (IL)-1β. Immunotherapeutic strategies have an important role in the suppression of cytokine storm and respiratory failure in patients with COVID-19.

METHODS

A systematic search in the literature was performed in PubMed, Scopus, Embase, Cochrane Library, Web of Science, as well as Google Scholar preprint database using all available MeSH terms for Coronavirus, SARS-CoV-2, anti-rheumatoid agents, COVID-19, cytokine storm, immunotherapeutic drugs, IFN, interleukin, JAK/STAT inhibitors, MCP, MIP, TNF.

RESULTS

Here, we first review common complications of COVID-19 patients, particularly neurological symptoms. We next explain host immune responses against COVID-19 particles. Finally, we summarize the existing experimental and clinical immunotherapeutic strategies, particularly anti-rheumatoid agents and also plasma (with a high level of gamma globulin) therapy for severe COVID-19 patients. We discuss both their therapeutic effects and side effects that should be taken into consideration for their clinical application.

CONCLUSION

It is suggested that immunosuppressants, such as anti-rheumatoid drugs, could be considered as a potential approach for the treatment of cytokine storm in severe cases of COVID-19. One possible limitation of immunosuppressant therapy is their inhibitory effects on host anti-viral immune response. So, the appropriate timing of administration should be carefully considered.

Role of the adaptive immune response in sepsis

Sepsis is a syndrome of shock and dysfunction of multiple vital organs that is caused by an uncontrolled immune response to infection and has a high mortality rate. There are no therapies for sepsis, and it has become a global cause for concern. Advances in patient care and management now mean that most patients survive the initial hyper-inflammatory phase of sepsis but progress to a later immunosuppressed phase, where 30% of patients die due to secondary infection. Deficits in the adaptive immune response may play a major role in sepsis patient mortality. The adaptive immune response involves a number of cell types including T cells, B cells and dendritic cells, all with immunoregulatory roles aimed at limiting damage and returning immune homeostasis after infection or insult. However, in sepsis, adaptive immune cells experience cell death or exhaustion, meaning that they have defective effector and memory responses ultimately resulting in an ineffective or suppressed immune defence. CD4+ T cells seem to be the most susceptible to cell death during sepsis and have ensuing defective secretory profiles and functions. Regulatory T cells seem to evade apoptosis and contribute to the immune suppression observed with sepsis. Preclinical studies have identified a number of new targets for therapy in sepsis including anti-apoptotic agents and monoclonal antibodies aimed at reducing cell death, exhaustion and maintaining/restoring adaptive immune cell functions. While early phase clinical trials have demonstrated safety and encouraging signals for biologic effect, larger scale clinical trial testing is required to determine whether these strategies will prove effective in improving outcomes from sepsis.

Interferon Beta-1b and Lopinavir-Ritonavir for Middle East Respiratory Syndrome

BACKGROUND

Whether combined treatment with recombinant interferon beta-1b and lopinavir-ritonavir reduces mortality among patients hospitalized with Middle East respiratory syndrome (MERS) is unclear.

METHODS

We conducted a randomized, adaptive, double-blind, placebo-controlled trial that enrolled patients at nine sites in Saudi Arabia. Hospitalized adults with laboratory-confirmed MERS were randomly assigned to receive recombinant interferon beta-1b plus lopinavir-ritonavir (intervention) or placebo for 14 days. The primary outcome was 90-day all-cause mortality, with a one-sided P-value threshold of 0.025. Prespecified subgroup analyses and safety analyses were conducted. Because of the pandemic of coronavirus disease 2019, the data and safety monitoring board requested an unplanned interim analysis and subsequently recommended the termination of enrollment and the reporting of the results.

RESULTS

A total of 95 patients were enrolled; 43 patients were assigned to the intervention group and 52 to the placebo group. A total of 12 patients (28%) in the intervention group and 23 (44%) in the placebo group died by day 90. The analysis of the primary outcome, with accounting for the adaptive design, yielded a risk difference of -19 percentage points (upper boundary of the 97.5% confidence interval [CI], -3; one-sided P = 0.024). In a prespecified subgroup analysis, treatment within 7 days after symptom onset led to lower 90-day mortality than use of placebo (relative risk, 0.19; 95% CI, 0.05 to 0.75), whereas later treatment did not. Serious adverse events occurred in 4 patients (9%) in the intervention group and in 10 (19%) in the placebo group.

CONCLUSIONS

A combination of recombinant interferon beta-1b and lopinavir-ritonavir led to lower mortality than placebo among patients who had been hospitalized with laboratory-confirmed MERS. The effect was greatest when treatment was started within 7 days after symptom onset. (Funded by the King Abdullah International Medical Research Center; MIRACLE ClinicalTrials.gov number, NCT02845843.).

Identification of atypical mitogen-activated protein kinase MAPK4 as a novel regulator in acute lung injury

Background

Acute lung injury (ALI) is a serious disease with highly morbidity and mortality that causes serious health problems worldwide. Atypical mitogen activated protein kinases (MAPKs) play critical roles in the development of tissues and have been proposed as promising therapeutic targets for various diseases. However, the potential role of atypical MAPKs in ALI remains elusive. In this study, we investigated the role of atypical MAPKs family member MAPK4 in ALI using LPS-induced murine ALI model.

Results

We found that MAPK4 deficiency mice exhibited prolonged survival time after LPS challenge, accompanied by alleviated pathology in lung tissues, decreased levels of pro-inflammatory cytokines and altered composition of immune cells in BALF. Furthermore, the transduction of related signaling pathways, including MK5, AKT, JNK, and p38 MAPK pathways, was reduced obviously in LPS-treated MAPK4^−/− mice. Notably, the expression of MAPK4 was up-regulated in lung tissues of ALI model, which was not related with MAPK4 promoter methylation, but negatively orchestrated by transcriptional factors NFKB1 and NR3C1. Further studies have shown that the expression of MAPK4 was also increased in LPS-treated macrophages. Meanwhile, MAPK4 deficiency reduced the expression of related pro-inflammatory cytokines in macrophage in response to LPS treatment. Finally, MAPK4 knockdown using shRNA pre-treatment could ameliorate the pathology of lung tissues and prolong the survival time of mice after LPS challenge.

Conclusions

Collectively, these findings reveal an important biological function of atypical MAPK in mediating the pathology of ALI, indicating that MAPK4 might be a novel potential therapeutic target for ALI treatment.

Pathophysiology and Potential Therapeutic Candidates for COVID-19: A Poorly Understood Arena

Coronavirus disease 2019 (COVID-19), an acute onset pneumonia caused by a novel Betacoronavirus, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged in the Wuhan City of China in December 2019 and evolved into a global pandemic. To date, there are no proven drugs or vaccines against this virus. Hence, the situation demands an urgent need to explore all potential therapeutic strategies that can be made available to prevent the disease progression and improve patient outcomes. In absence of clinically proven treatment guidelines, several repurposed drugs and investigational agents are currently being evaluated in clinical trials for their probable benefits in the treatment of COVID-19. These include antivirals (remdesivir, lopinavir/ritonavir, umifenovir, and favipiravir), interferon, antimalarials (chloroquine/hydroxychloroquine), antiparasitic drugs (ivermectin and nitazoxanide), biologics (monoclonal antibodies and interleukin receptor antagonist), cellular therapies (mesenchymal stem cells and natural killer cells), convalescent plasma, and cytokine adsorber. Though several observational studies have claimed many of these agents to be effective based on their in vitro activities and extrapolated evidence from SARS and Middle East respiratory syndrome (MERS) epidemics, the currently available data remains inconclusive because of ill-defined patient selection criteria, small sample size, lack of concurrent controls, and use of intermediary outcomes instead of patient-relevant outcomes. Moreover, there is a need to clearly define the patient populations who warrant therapy and also the timing of initiation of treatment. Understanding the disease pathology responsible for the clinical manifestations of COVID-19 is imperative to identify the potential targets for drug development. This review explains the pathophysiology of COVID-19 and summarizes the potential treatment candidates, which can provide guidance in developing effective therapeutic strategies.

Repurposing Immunomodulatory Therapies against Coronavirus Disease 2019 (COVID-19) in the Era of Cardiac Vigilance: A Systematic Review

The ongoing coronavirus disease 2019 (COVID-19) pandemic has resulted in efforts to identify therapies to ameliorate adverse clinical outcomes. The recognition of the key role for increased inflammation in COVID-19 has led to a proliferation of clinical trials targeting inflammation. The purpose of this review is to characterize the current state of immunotherapy trials in COVID-19, and focuses on associated cardiotoxicities, given the importance of pharmacovigilance. The search terms related to COVID-19 were queried in ClinicalTrials.gov. A total of 1621 trials were identified and screened for interventional trials directed at inflammation. Trials (n = 226) were fully assessed for the use of a repurposed drug, identifying a total of 141 therapeutic trials using a repurposed drug to target inflammation in COVID-19 infection. Building on the results of the Randomized Evaluation of COVID-19 Therapy (RECOVERY) trial demonstrating the benefit of low dose dexamethasone in COVID-19, repurposed drugs targeting inflammation are promising. Repurposed drugs directed at inflammation in COVID-19 primarily have been drawn from cancer therapies and immunomodulatory therapies, specifically targeted anti-inflammatory, anti-complement, and anti-rejection agents. The proposed mechanisms for many cytokine-directed and anti-rejection drugs are focused on evidence of efficacy in cytokine release syndromes in humans or animal models. Anti-complement-based therapies have the potential to decrease both inflammation and microvascular thrombosis. Cancer therapies are hypothesized to decrease vascular permeability and inflammation. Few publications to date describe using these drugs in COVID-19. Early COVID-19 intervention trials have re-emphasized the subtle, but important cardiotoxic sequelae of potential therapies on outcomes. The volume of trials targeting the COVID-19 hyper-inflammatory phase continues to grow rapidly with the evaluation of repurposed drugs and late-stage investigational agents. Leveraging known clinical safety profiles and pharmacodynamics allows swift investigation in clinical trials for a novel indication. Physicians should remain vigilant for cardiotoxicity, often not fully appreciated in small trials or in short time frames.

A Randomized Clinical Trial of the Efficacy and Safety of Interferon β-1a in Treatment of Severe COVID-19

To the best of our knowledge, there is no published study on the use of interferon β-1a (IFN β-1a) in the treatment of severe COVID-19. In this randomized clinical trial, the efficacy and safety of IFN β-1a were evaluated in patients with severe COVID-19. Forty-two patients in the interferon group received IFN β-1a in addition to the national protocol medications (hydroxychloroquine plus lopinavir-ritonavir or atazanavir-ritonavir). Each 44-μg/ml (12 million IU/ml) dose of interferon β-1a was subcutaneously injected three times weekly for two consecutive weeks. The control group consisted of 39 patients who received only the national protocol medications. The primary outcome of the study was time to reach clinical response. Secondary outcomes were duration of hospital stay, length of intensive care unit stay, 28-day mortality, effect of early or late administration of IFN on mortality, adverse effects, and complications during the hospitalization. Between 29 February and 3 April 2020, 92 patients were recruited, and a total of 42 patients in the IFN group and 39 patients in the control group completed the study. As the primary outcome, time to the clinical response was not significantly different between the IFN and the control groups (9.7 ± 5.8 versus 8.3 ± 4.9 days, respectively, P = 0.95). On day 14, 66.7% versus 43.6% of patients in the IFN group and the control group, respectively, were discharged (odds ratio [OR], 2.5; 95% confidence interval [CI], 1.05 to 6.37). The 28-day overall mortality was significantly lower in the IFN than the control group (19% versus 43.6%, respectively, P = 0.015). Early administration significantly reduced mortality (OR, 13.5; 95% CI, 1.5 to 118). Although IFN did not change the time to reach the clinical response, adding it to the national protocol significantly increased discharge rate on day 14 and decreased 28-day mortality. (This study is in the Iranian Registry of Clinical Trials under identifier IRCT20100228003449N28.).

Antivirals Against Coronaviruses: Candidate Drugs for SARS-CoV-2 Treatment?

Coronaviruses (CoVs) are a group of viruses from the family Coronaviridae that can infect humans and animals, causing mild to severe diseases. The ongoing pandemic of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) represents a global threat, urging the development of new therapeutic strategies. Here we present a selection of relevant compounds that have been described from 2005 until now as having in vitro and/or in vivo antiviral activities against human and/or animal CoVs. We also present compounds that have reached clinical trials as well as further discussing the potentiality of other molecules for application in (re)emergent CoVs outbreaks. Finally, through rationalization of the data presented herein, we wish to encourage further research encompassing these compounds as potential SARS-CoV-2 drug candidates.

An overview of key potential therapeutic strategies for combat in the COVID-19 battle

The sudden ravaging outbreak of a novel coronavirus, or SARS-CoV-2, in terms of virulence, severity, and casualties has already overtaken previous versions of coronaviruses, like SARS CoV and MERS CoV. Originating from its epicenter in Wuhan, China, this mutated version of the influenza virus with its associated pandemic effects has engulfed the whole world with awful speed. In the midst of this bewildering situation, medical and scientific communities are on their toes to produce the potential vaccine-mediated eradication of this virus. Though the chances are really high, to date no such panacea has been reported. The time requirements for the onerous procedures of human trials for the successful clinical translation of any vaccine or potential therapeutics are also a major concern. In order to build some resistance against this massive pandemic, the repurposing of some earlier antiviral drugs has been done, along with the refurbishment of some immune-responsive alternative avenues, like monoclonal antibody mediated neutralization, interferon treatment, and plasma therapy. New drugs developed from the RBD domain of the virus spike protein and drugs targeting viral proteases are also undergoing further research and have shown potential from preliminary results. The sole purpose of this review article is to provide a brief collective overview of the recent status of therapeutics advances and approaches, and their current state of implementation for the management of COVID-19.

Subcutaneous administration of interferon beta-1a for COVID-19: A non-controlled prospective trial

Background

Recently, a new coronavirus spreads rapidly throughout the countries and resulted in a worldwide epidemic. Interferons have direct antiviral and immunomodulatory effects. Antiviral effects may include inhibition of viral replication, protein synthesis, virus maturation, or virus release from infected cells. Previous studies have shown that some coronaviruses are susceptible to interferons. The aim of this study was to evaluate the therapeutic effects of IFN-β-1a administration in COVID-19.

Methods

In this prospective non-controlled trial, 20 patients included. They received IFN-β-1a at a dose of 44 µg subcutaneously every other day up to 10 days. All patients received conventional therapy including Hydroxychloroquine, and lopinavir/ritonavir. Demographic data, clinical symptoms, virological clearance, and imaging findings recorded during the study.

Results

The mean age of the patients was 58.55 ± 13.43 years. Fever resolved in all patients during first seven days. Although other symptoms decreased gradually. Virological clearance results showed a significant decrease within 10 days. Imaging studies showed significant recovery after 14-day period in all patients. The mean time of hospitalization was 16.8 ± 3.4 days. There were no deaths or significant adverse drug reactions in the 14-day period.

Conclusions

Our findings support the use of IFN-β-1a in combination with hydroxychloroquine and lopinavir/ritonavir in the management of COVID-19.

Clinical trial registration number: IRCT20151227025726N12.

Efficacy and safety of aerosol inhalation of recombinant human interferon α1b (IFNα1b) injection for noninfluenza viral pneumonia, a multicenter, randomized, double-blind, placebo-controlled trial

Background

To investigate the efficacy and safety of aerosol inhalation of recombinant human interferon α1b (IFNα1b) injection for noninfluenza viral pneumonia.

Methods

One hundred sixty-four patients with noninfluenza viral pneumonia were divided into IFNα1b and control groups. The IFNα1b group received routine treatment + aerosol inhalation of recombinant human IFNα1b injection (50 μg × 2 injections, bid). The control group received routine treatment + IFN analog (two injections, bid). Overall response rate (ORR) of five kinds clinical symptoms. Further outcomes were daily average score and the response rate of each of the symptoms above.

Results

A total of 163 patients were included in the full analysis set (FAS) and 151 patients were included in the per-protocol set (PPS). After 7 days of treatment, ORR of clinical symptoms was higher in IFNα1b group than that in control group for both the FAS and PPS. Moreover, after 7 days of treatment, the daily score of three efficacy indexes including expectoration, respiratory rate, and pulmonary rales were improved. The ORRs for expectoration and pulmonary rales were higher in the IFNα1b group than in the control group (P < 0.05). There were no significant differences of the ORRs for coughing, chest pain and respiratory rate between the two groups (P > 0.05). The incidence of adverse events was 6.5% (n = 5) in IFNα1b group and 3.5% (n = 3) in control group (P > 0.05).

Conclusion

Aerosol inhalation of recombinant human IFNα1b is safe and it can improve the clinical symptoms of noninfluenza viral pneumonia.

The Rationale for Potential Pharmacotherapy of COVID-19

On 11 March 2020, the coronavirus disease (COVID-19) was defined by the World Health Organization as a pandemic. Severe acute respiratory syndrome-2 (SARS-CoV-2) is the newly evolving human coronavirus infection that causes COVID-19, and it first appeared in Wuhan, China in December 2019 and spread rapidly all over the world. COVID-19 is being increasingly investigated through virology, epidemiology, and clinical management strategies. There is currently no established consensus on the standard of care in the pharmacological treatment of COVID-19 patients. However, certain medications suggested for other diseases have been shown to be potentially effective for treating this infection, though there has yet to be clear evidence. Therapies include new agents that are currently tested in several clinical trials, in addition to other medications that have been repurposed as antiviral and immune-modulating therapies. Previous high-morbidity human coronavirus epidemics such as the 2003 SARS-CoV and the 2012 Middle East respiratory syndrome coronavirus (MERS-CoV) prompted the identification of compounds that could theoretically be active against the emerging coronavirus SARS-CoV-2. Moreover, advances in molecular biology techniques and computational analysis have allowed for the better recognition of the virus structure and the quicker screening of chemical libraries to suggest potential therapies. This review aims to summarize rationalized pharmacotherapy considerations in COVID-19 patients in order to serve as a tool for health care professionals at the forefront of clinical care during this pandemic. All the reviewed therapies require either additional drug development or randomized large-scale clinical trials to be justified for clinical use.

Circulating miRNA 887 is differentially expressed in ARDS and modulates endothelial function

Circulating microRNAs (miRNAs) can be taken up by recipient cells and have been recently associated with the acute respiratory distress syndrome (ARDS). Their role in host predisposition to the syndrome is unknown. The objective of the study was to identify circulating miRNAs associated with the development of sepsis-related ARDS and examine their impact on endothelial cell gene expression and function. We determined miRNA levels in plasma collected from subjects during the first 24 h of admission to a tertiary intensive care unit for sepsis. A miRNA that was differentially expressed between subjects who did and did not develop ARDS was identified and was transfected into human pulmonary microvascular endothelial cells (HPMECs). RNA sequencing, in silico analysis, cytokine expression, and leukocyte migration assays were used to determine the impact of this miRNA on gene expression and cell function. In two cohorts, circulating miR-887-3p levels were elevated in septic patients who developed ARDS compared with those who did not. Transfection of miR-887-3p into HPMECs altered gene expression, including the upregulation of several genes previously associated with ARDS (e.g., CXCL10, CCL5, CX3CL1, VCAM1, CASP1, IL1B, IFNB, and TLR2), and activation of cellular pathways relevant to the response to infection. Functionally, miR-887-3p increased the endothelial release of chemokines and facilitated trans-endothelial leukocyte migration. Circulating miR-887-3p is associated with ARDS in critically ill patients with sepsis. In vitro, miR-887-3p regulates the expression of genes relevant to ARDS and neutrophil tracking. This miRNA may contribute to ARDS pathogenesis and could represent a novel therapeutic target.

Type 1 interferons as a potential treatment against COVID-19

Type 1 interferons have a broad antiviral activity in vitro and are currently evaluated in a clinical trial to treat MERS-CoV. In this review, we discuss preliminary data concerning the potential activity of type 1 interferons on SARS-CoV-2, and the relevance of evaluating these molecules in clinical trials for the treatment of COVID-19.

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Interferon treatment has shown mixed efficiency against SARS-CoV and MERS-CoV.

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SARS-CoV-2 is probably more sensitive to interferon than the other coronaviruses.

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The IFNβ subtype appears to be the most suited for COVID-19 treatment.

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Interferon treatment should be performed in the early stages of the infection.

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Investigation on interferon-based COVID-19 treatment is warranted.

COVID-19 pandemic: A review based on current evidence

In December 2019, severe acute respiratory syndrome-coronavirus-2, a novel coronavirus, initiated an outbreak of pneumonia from Wuhan in China, which rapidly spread worldwide. The clinical characteristics of the disease range from asymptomatic cases or mild symptoms, which include nonspecific symptoms such as fever, cough, sore throat, headache, and nasal congestion to severe cases such as pneumonia, respiratory failure demanding mechanical ventilation to multi-organ failure, sepsis, and death. As the transmission rate is quite alarming, we require an effective therapeutic strategy to treat symptomatic patients and adopt the preventive measures in order to contain the infection and prevent community transmission. Coronavirus disease 2019 (COVID-19) pandemic is a public health emergency of international concern, hence repurposing of the drugs is an attractive and a feasible option because PK/PD profile, toxicity profile, and drug interactions are already known. This review emphasizes on the different aspects of COVID-19 such as the epidemiology, etiopathogenesis, diagnosis, and preventive measures to be adopted in order to fight this pandemic. It also highlights upon the ethics preparedness and challenges faced by a developing country like India during such an outbreak. The review focuses on the various approaches adopted till date for developing effective therapeutic strategies including combination of drugs, vaccine therapy, and convalescent plasma therapy to combat this viral outbreak.

Effect of Intravenous Interferon β-1a on Death and Days Free From Mechanical Ventilation Among Patients With Moderate to Severe Acute Respiratory Distress Syndrome: A Randomized Clinical Trial

IMPORTANCE

Acute respiratory distress syndrome (ARDS) is associated with high mortality. Interferon (IFN) β-1a may prevent the underlying event of vascular leakage.

OBJECTIVE

To determine the efficacy and adverse events of IFN-β-1a in patients with moderate to severe ARDS.

DESIGN, SETTING, AND PARTICIPANTS

Multicenter, randomized, double-blind, parallel-group trial conducted at 74 intensive care units in 8 European countries (December 2015-December 2017) that included 301 adults with moderate to severe ARDS according to the Berlin definition. The radiological and partial pressure of oxygen, arterial (Pao2)/fraction of inspired oxygen (Fio2) criteria for ARDS had to be met within a 24-hour period, and the administration of the first dose of the study drug had to occur within 48 hours of the diagnosis of ARDS. The last patient visit was on March 6, 2018.

INTERVENTIONS

Patients were randomized to receive an intravenous injection of 10 μg of IFN-β-1a (144 patients) or placebo (152 patients) once daily for 6 days.

MAIN OUTCOMES AND MEASURES

The primary outcome was a score combining death and number of ventilator-free days at day 28 (score ranged from -1 for death to 27 if the patient was off ventilator on the first day). There were 16 secondary outcomes, including 28-day mortality, which were tested hierarchically to control type I error.

RESULTS

Among 301 patients who were randomized (mean age, 58 years; 103 women [34.2%]), 296 (98.3%) completed the trial and were included in the primary analysis. At 28 days, the median composite score of death and number of ventilator-free days at day 28 was 10 days (interquartile range, -1 to 20) in the IFN-β-1a group and 8.5 days (interquartile range, 0 to 20) in the placebo group (P = .82). There was no significant difference in 28-day mortality between the IFN-β-1a vs placebo groups (26.4% vs 23.0%; difference, 3.4% [95% CI, -8.1% to 14.8%]; P = .53). Seventy-four patients (25.0%) experienced adverse events considered to be related to treatment during the study (41 patients [28.5%] in the IFN-β-1a group and 33 [21.7%] in the placebo group).

CONCLUSIONS AND RELEVANCE

Among adults with moderate or severe ARDS, intravenous IFN-β-1a administered for 6 days, compared with placebo, resulted in no significant difference in a composite score that included death and number of ventilator-free days over 28 days. These results do not support the use of IFN-β-1a in the management of ARDS.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02622724.

Approaches for the Treatment of SARS-CoV-2 Infection: A Pharmacologic View and Literature Review

The emergence of a novel Coronavirus disease (COVID-19) inducing acute respiratory distress syndrome (ARDS) was identified in Hubei province of China in December 2019 and rapidly spread worldwide as pandemic and became a public health concern. COVID-19 disease is caused by a new virus known as SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2), which has recently offered many challenges and efforts to identify effective drugs for its prevention and treatment. Currently, there is no proven effective approach and medication against this virus. Quickly expanding clinical trials and studies on Coronavirus disease 2019 increase our knowledge regarding SARS-CoV-2 virus and introduce several potential drugs targeting virus moiety or host cell elements. Overall, 3 stages were suggested for SARS-CoV-2 infection according to the disease severity, clinical manifestations, and treatment outcomes, including mild, moderate, and severe. This review aimed to classify and summarize several medications and potential therapies according to the disease 3 stages; however, it is worth noting that no medication and therapy has been effective so far.

CD73; a key ectonucleotidase in the development of breast cancer: Recent advances and perspectives

Tumor cell invasion and metastasis are the definitive cause of mortality in breast cancer (BC). Hypoxia and pro-inflammatory cytokines upregulate the CD73 gene in the tumor microenvironment. Subsequently, CD73 triggers molecular and cellular signaling pathways by both enzymatic and nonenzymatic pathways, which finally leads to breast tumor progression and development. In this paper, we summarize current advances in the understanding of CD73-driven mechanisms that promote BC development and mortality. Furthermore, we evaluate the therapeutic potential of CD73 targeting in BC.

Cell type- and tissue-specific functions of ecto-5'-nucleotidase (CD73)

Ecto-5'-nucleotidase [cluster of differentiation 73 (CD73)] is a ubiquitously expressed glycosylphosphatidylinositol-anchored glycoprotein that converts extracellular adenosine 5'-monophosphate to adenosine. Anti-CD73 inhibitory antibodies are currently undergoing clinical testing for cancer immunotherapy. However, many protective physiological functions of CD73 need to be taken into account for new targeted therapies. This review examines CD73 functions in multiple organ systems and cell types, with a particular focus on novel findings from the last 5 years. Missense loss-of-function mutations in the CD73-encoding gene NT5E cause the rare disease "arterial calcifications due to deficiency of CD73." Aside from direct human disease involvement, cellular and animal model studies have revealed key functions of CD73 in tissue homeostasis and pathology across multiple organ systems. In the context of the central nervous system, CD73 is antinociceptive and protects against inflammatory damage, while also contributing to age-dependent decline in cortical plasticity. CD73 preserves barrier function in multiple tissues, a role that is most evident in the respiratory system, where it inhibits endothelial permeability in an adenosine-dependent manner. CD73 has important cardioprotective functions during myocardial infarction and heart failure. Under ischemia-reperfusion injury conditions, rapid and sustained induction of CD73 confers protection in the liver and kidney. In some cases, the mechanism by which CD73 mediates tissue injury is less clear. For example, CD73 has a promoting role in liver fibrosis but is protective in lung fibrosis. Future studies that integrate CD73 regulation and function at the cellular level with physiological responses will improve its utility as a disease target.

Immunometabolic Dysfunction of Natural Killer Cells Mediated by the Hypoxia-CD73 Axis in Solid Tumors

NK cell infiltration into solid tumors is often low and is largely represented by the poorly-cytotoxic CD56^bright subset. Numerous studies have demonstrated that CD73, overexpressed under conditions of hypoxia, is involved in a variety of physiological processes, while its overexpression has been correlated with tumor invasiveness, metastasis and poorer patient survival in many cancers. Hypoxia itself favors aggressive glycolytic fueling of cancer cells, in turn driving reprogramming of NK cell metabolism. In addition, the hypoxia-driven activity of CD73 immunometabolically impairs NK cells in tumors, due to its catalytic role in the generation of the highly immunosuppressive metabolite adenosine. Adenosinergic signaling was shown to alter NK cell metabolic programs, leading to tumor-promoting environments characterized by NK cell dysfunction. Despite the demonstrated role of NK cell responses in the context of CD73 targeting, the engagement of NK cells in the setting of hypoxia/CD73 signaling has not been extensively studied or exploited. Here, we discuss available evidence on the role of hypoxic signaling on CD73-mediated activity, and how this relates to the immunometabolic responses of NK cells, with a particular focus on the therapeutic targeting of these pathways.

Purinergic Signaling in Pulmonary Inflammation

Purine nucleotides and nucleosides are at the center of biologic reactions. In particular, adenosine triphosphate (ATP) is the fundamental energy currency of cellular activity and adenosine has been demonstrated to play essential roles in human physiology and pathophysiology. In this review, we examine the role of purinergic signaling in acute and chronic pulmonary inflammation, with emphasis on ATP and adenosine. ATP is released into extracellular space in response to cellular injury and necrosis. It is then metabolized to adenosine monophosphate (AMP) via ectonucleoside triphosphate diphosphohydrolase-1 (CD39) and further hydrolyzed to adenosine via ecto-5'-nucleotidase (CD73). Adenosine signals via one of four adenosine receptors to exert pro- or anti-inflammatory effects. Adenosine signaling is terminated by intracellular transport by concentrative or equilibrative nucleoside transporters (CNTs and ENTs), deamination to inosine by adenosine deaminase (ADA), or phosphorylation back into AMP via adenosine kinase (AK). Pulmonary inflammatory and hypoxic conditions lead to increased extracellular ATP, adenosine diphosphate (ADP) and adenosine levels, which translates to increased adenosine signaling. Adenosine signaling is central to the pulmonary injury response, leading to various effects on inflammation, repair and remodeling processes that are either tissue-protective or tissue destructive. In the acute setting, particularly through activation of adenosine 2A and 2B receptors, adenosine signaling serves an anti-inflammatory, tissue-protective role. However, excessive adenosine signaling in the chronic setting promotes pro-inflammatory, tissue destructive effects in chronic pulmonary inflammation.

Enzyme activity of circulating CD73 in human serum

CD73 is an ectonucleotidase able to catabolize 5'-adenosine monophosphate (AMP) into adenosine at the extracellular level. Extracellular adenosine plays a critical role in regulating many processes under physiological and pathological conditions. In the context of cancer, the expression and activity of CD73, either in tissue and in biological fluids, is increased leading to high levels of adenosine that potently suppress T-cell mediated responses, promoting tumor progression through stimulation of adenosine receptors. Compelling evidence indicates that elevated levels of CD73-generating adenosine limit the efficacy of cancer immunotherapy. Inhibitors of ectonucleotidases and antagonists of adenosine receptors have emerged as new therapeutic tools to improve anti-tumor immune response and potentially synergize with currently used immunotherapeutic agents. Measurement of CD73 levels in serum of cancer patients is a promising approach that, although it needs to be validated, may help to select patients who will benefit from adenosine-targeting agents and predict response to immunotherapy. Here, we describe a simple and fast method to evaluate the AMPase activity of CD73 in peripheral blood that may also be applied to other biological fluids.

Targeting Adenosine in Cancer Immunotherapy to Enhance T-Cell Function

T cells play a critical role in cancer control, but a range of potent immunosuppressive mechanisms can be upregulated in the tumor microenvironment (TME) to abrogate their activity. While various immunotherapies (IMTs) aiming at re-invigorating the T-cell-mediated anti-tumor response, such as immune checkpoint blockade (ICB), and the adoptive cell transfer (ACT) of natural or gene-engineered ex vivo expanded tumor-specific T cells, have led to unprecedented clinical responses, only a small proportion of cancer patients benefit from these treatments. Important research efforts are thus underway to identify biomarkers of response, as well as to develop personalized combinatorial approaches that can target other inhibitory mechanisms at play in the TME. In recent years, adenosinergic signaling has emerged as a powerful immuno-metabolic checkpoint in tumors. Like several other barriers in the TME, such as the PD-1/PDL-1 axis, CTLA-4, and indoleamine 2,3-dioxygenase (IDO-1), adenosine plays important physiologic roles, but has been co-opted by tumors to promote their growth and impair immunity. Several agents counteracting the adenosine axis have been developed, and pre-clinical studies have demonstrated important anti-tumor activity, alone and in combination with other IMTs including ICB and ACT. Here we review the regulation of adenosine levels and mechanisms by which it promotes tumor growth and broadly suppresses protective immunity, with extra focus on the attenuation of T cell function. Finally, we present an overview of promising pre-clinical and clinical approaches being explored for blocking the adenosine axis for enhanced control of solid tumors.

Integrating molecular pathogenesis and clinical translation in sepsis-induced acute respiratory distress syndrome

Sepsis-induced acute respiratory distress syndrome (ARDS) has high morbidity and mortality and arises after lung infection or infection at extrapulmonary sites. An aberrant host response to infection leads to disruption of the pulmonary alveolar-capillary barrier, resulting in lung injury characterized by hypoxemia, inflammation, and noncardiogenic pulmonary edema. Despite increased understanding of the molecular biology underlying sepsis-induced ARDS, there are no targeted pharmacologic therapies for this devastating condition. Here, we review the molecular underpinnings of sepsis-induced ARDS with a focus on relevant clinical and translational studies that point toward novel therapeutic strategies.