Interferon-beta 1a and SARS coronavirus replication

Harnessing the power of IFN for therapeutic approaches to COVID-19

Interferons (IFNs) are essential for defense against viral infections but also drive recruitment of inflammatory cells to sites of infection, a key feature of severe COVID-19. Here, we explore the complexity of the IFN response in COVID-19, examine the effects of manipulating IFN on SARS-CoV-2 viral replication and pathogenesis, and highlight pre-clinical and clinical studies evaluating the therapeutic efficacy of IFN in limiting COVID-19 severity.

FHL2 Inhibits SARS-CoV-2 Replication by Enhancing IFN-β Expression through Regulating IRF-3

SARS-CoV-2 triggered the global COVID-19 pandemic, posing a severe threat to public health worldwide. The innate immune response in cells infected by SARS-CoV-2 is primarily orchestrated by type I interferon (IFN), with IFN-β exhibiting a notable inhibitory impact on SARS-CoV-2 replication. FHL2, acting as a docking site, facilitates the assembly of multiprotein complexes and regulates the transcription of diverse genes. However, the association between SARS-CoV-2 and FHL2 remains unclear. In this study, we report for the first time that SARS-CoV-2 infection in Caco2 cells results in the upregulation of FHL2 expression, while the virus's N proteins can enhance FHL2 expression. Notably, the knockdown of FHL2 significantly amplifies SARS-CoV-2 replication in vitro. Conversely, the overexpression of FHL2 leads to a marked reduction in SARS-CoV-2 replication, with the antiviral property of FHL2 being independent of the cell or virus type. Subsequent experiments reveal that FHL2 supports IFN-β transcription by upregulating the expression and phosphorylation of IRF-3, thereby impeding SARS-CoV-2 replication in cells. These findings highlight FHL2 as a potential antiviral target for treating SARS-CoV-2 infections.

An important call: Suggestion of using IL-10 as therapeutic agent for COVID-19 with ARDS and other complications

The global coronavirus disease 2019 (COVID-19) pandemic has a detrimental impact on public health. COVID-19 usually manifests as pneumonia, which can progress into acute respiratory distress syndrome (ARDS) related to uncontrolled TH17 immune reaction. Currently, there is no effective therapeutic agent to manage COVID-19 with complications. The currently available anti-viral drug remdesivir has an effectiveness of 30% in SARS-CoV-2-induced severe complications. Thus, there is a need to identify effective agents to treat COVID-19 and the associated acute lung injury and other complications. The host immunological pathway against this virus typically involves the THαβ immune response. THαβ immunity is triggered by type 1 interferon and interleukin-27 (IL-27), and the main effector cells of the THαβ immune response are IL10-CD4 T cells, CD8 T cells, NK cells, and IgG1-producing B cells. In particular, IL-10 exerts a potent immunomodulatory or anti-inflammatory effect and is an anti-fibrotic agent for pulmonary fibrosis. Concurrently, IL-10 can ameliorate acute lung injury or ARDS, especially those caused by viruses. Owing to its anti-viral activity and anti-pro-inflammatory effects, in this review, IL-10 is suggested as a possible treatment agent for COVID-19.

Safety and efficacy of inhaled interferon-β1a (SNG001) in adults with mild-to-moderate COVID-19: a randomized, controlled, phase II trial

Background

With the emergence of SARS-CoV-2 variants resistant to monoclonal antibody therapies and limited global access to therapeutics, the evaluation of novel therapeutics to prevent progression to severe COVID-19 remains a critical need.

Methods

Safety, clinical and antiviral efficacy of inhaled interferon-β1a (SNG001) were evaluated in a phase II randomized controlled trial on the ACTIV-2/A5401 platform (ClinicalTrials.govNCT04518410). Adult outpatients with confirmed SARS-CoV-2 infection within 10 days of symptom onset were randomized and initiated either orally inhaled nebulized SNG001 given once daily for 14 days (n = 110) or blinded pooled placebo (n = 110) between February 10 and August 18, 2021.

Findings

The proportion of participants reporting premature treatment discontinuation was 9% among SNG001 and 13% among placebo participants. There were no differences between participants who received SNG001 or placebo in the primary outcomes of treatment emergent Grade 3 or higher adverse events (3.6% and 8.2%, respectively), time to symptom improvement (median 13 and 9 days, respectively), or proportion with unquantifiable nasopharyngeal SARS-CoV-2 RNA at days 3 (28% [26/93] vs. 39% [37/94], respectively), 7 (65% [60/93] vs. 66% [62/94]) and 14 (91% [86/95] vs. 91% [83/81]). There were fewer hospitalizations with SNG001 (n = 1; 1%) compared with placebo (n = 7; 6%), representing an 86% relative risk reduction (p = 0.07). There were no deaths in either arm.

Interpretation

In this trial, SNG001 was safe and associated with a non-statistically significant decrease in hospitalization for COVID-19 pneumonia.

Funding

The ACTIV-2 platform study is funded by the NIH. Research reported in this publication was supported by the National Institute of Allergy and Infectious Diseases of the National Institutes of Health under Award Number UM1 AI068634, UM1 AI068636 and UM1 AI106701. The content is solely the responsibility of the authors and does not necessarily represent the official views of the National Institutes of Health.

Interferon beta-1a sc at 25 years: a mainstay in the treatment of multiple sclerosis over the period of one generation

INTRODUCTION

Interferon beta (IFN beta) preparations are an established group of drugs used for immunomodulation in patients with multiple sclerosis (MS). Subcutaneously (sc) applied interferon beta-1a (IFN beta-1a sc) has been in continuous clinical use for 25 years as a disease-modifying treatment.

AREAS COVERED

Based on data published since 2018, we discuss recent insights from analyses of the pivotal trial PRISMS and its long-term extension as well as from newer randomized studies with IFN beta-1a sc as the reference treatment, the use of IFN beta-1a sc across the patient life span and as a bridging therapy, recent data regarding the mechanisms of action, and potential benefits of IFN beta-1a sc regarding vaccine responses.

EXPERT OPINION

IFN beta-1a sc paved the way to effective immunomodulatory treatment of MS, enabled meaningful insights into the disease process, and remains a valid therapeutic option in selected vulnerable MS patient groups.

Reconsideration of interferon treatment for viral diseases: Lessons from SARS, MERS, and COVID-19

Periodic pandemics of coronavirus (CoV)-related pneumonia have been a major challenging issue since the outbreak of severe acute respiratory syndrome (SARS) in 2002 and Middle East respiratory syndrome (MERS) in 2012. The ongoing pandemic of CoV disease (COVID-19) poses a substantial threat to public health. As for the treatment options, only limited antiviral agents have been approved hitherto, and clinicians mainly focus on currently available drugs including the conventional antiviral interferons (IFNs). In clinical practice, IFNs, when used either alone or in combination with ribavirin and/or lopinavir/ritonavir, have shown promising outcomes, to some extent, in SARS-CoV or MERS-CoV treatment. Although the efficacy and safety of IFNs in COVID-19 treatment remain unclear, their possible use merits further evaluation. We present a review that summarizes current evidence of IFN treatment for COVID-19 and elaborates on other challenges in terms of the timing of IFN treatment initiation, treatment duration, and IFN type to be used. The review findings suggested that IFN acts by directly inhibiting viral replication and activating immune cell subsets. However, there is a lack of well-designed and controlled clinical trials providing firm evidence for the efficacy or safety of IFN therapy for CoVs. Additionally, critically ill patients with multiple immunosuppression-associated comorbidities may not benefit from IFN therapy, necessitating screening of those patients who would most benefit from IFN treatment.

Association of Disease-Modifying Therapies with COVID-19 Susceptibility and Severity in Patients with Multiple Sclerosis: A Systematic Review and Network Meta-Analysis

Background

We conducted this study to assess the effect of disease-modifying therapies (DMTs) on coronavirus disease (COVID-19) susceptibility and severity in people with multiple sclerosis (MS).

Methods

Available studies from PubMed, Scopus, EMBASE, Web of Science, and gray literature, including reference lists and conference abstracts, were searched from December 1, 2019, to July 26, 2021. We included cross-sectional, case-control, and cohort studies assessing the association of DMTs with risk of contracting COVID-19 or its outcomes in MS patients on univariate or multivariate regression analyses. We conducted a network meta-analysis (NMA) to compare the risk of COVID-19 and developing severe infection across DMTs.

Results

Out of the initial 3893 records and 1883 conference abstracts, a total of 10 studies were included. Pairwise comparisons showed that none of the DMTs meaningfully affect the risk of acquiring infection. There was significant total heterogeneity and inconsistency across this NMA. In comparison with no DMT, dimethyl fumarate (0.62 (0.42, 0.93)), fingolimod (0.55 (0.32, 0.94)), natalizumab (0.50 (0.31, 0.81)), and interferon (0.42 (0.22, 0.79)) were associated with a decreased risk of severe COVID-19; but, rituximab was observed to increase the risk (1.94 (1.20, 3.12)). Compared to rituximab or ocrelizumab, all DMTs were associated with a decreased risk. Pairwise comparisons showed no differences across other DMTs. Interferon and rituximab were associated with the lowest and highest risks of severe COVID-19.

Conclusion

Our study showed an increased risk of severe COVID-19 in patients on rituximab and ocrelizumab. No association with COVID-19 severity across other DMTs was observed.

Scope of repurposed drugs against the potential targets of the latest variants of SARS-CoV-2

The unprecedented outbreak of the severe acute respiratory syndrome (SARS) Coronavirus-2, across the globe, triggered a worldwide uproar in the search for immediate treatment strategies. With no specific drug and not much data available, alternative approaches such as drug repurposing came to the limelight. To date, extensive research on the repositioning of drugs has led to the identification of numerous drugs against various important protein targets of the coronavirus strains, with hopes of the drugs working against the major variants of concerns (alpha, beta, gamma, delta, omicron) of the virus. Advancements in computational sciences have led to improved scope of repurposing via techniques such as structure-based approaches including molecular docking, molecular dynamic simulations and quantitative structure activity relationships, network-based approaches, and artificial intelligence-based approaches with other core machine and deep learning algorithms. This review highlights the various approaches to repurposing drugs from a computational biological perspective, with various mechanisms of action of the drugs against some of the major protein targets of SARS-CoV-2. Additionally, clinical trials data on potential COVID-19 repurposed drugs are also highlighted with stress on the major SARS-CoV-2 targets and the structural effect of variants on these targets. The interaction modelling of some important repurposed drugs has also been elucidated. Furthermore, the merits and demerits of drug repurposing are also discussed, with a focus on the scope and applications of the latest advancements in repurposing.

The impact of SARS-CoV-2 treatment on the cardiovascular system: an updated review

The coronavirus disease-2019 (COVID-19) pandemic has become a major global health problem. COVID-19 is caused by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and exhibits pulmonary and extrapulmonary effects, including cardiovascular involvement. There are several attempts to identify drugs that could treat COVID-19. Moreover, many patients infected with COVID-19 have underlying diseases, particularly cardiovascular diseases. These patients are more likely to develop severe illnesses and would require optimized treatment strategies. The current study gathered information from various databases, including relevant studies, reviews, trials, or meta-analyses until April 2022 to identify the impact of SARS-CoV-2 treatment on the cardiovascular system. Studies have shown that the prognosis of patients with underlying cardiovascular disease is worsened by COVID-19, with some COVID-19 medications interfering with the cardiovascular system. The COVID-19 treatment strategy should consider many factors and parameters to avoid medication-induced cardiac injury, mainly in elderly patients. Therefore, this article provides a synthesis of evidence on the impact of different COVID-19 medications on the cardiovascular system and related disease conditions.

Clinical Manifestations, Imaging Procedures and Laboratory Parameters among Hospitalized Patients with COVID-19 in Ilam Province, Western Iran

Background

COVID-19 is the last global threat which WHO confirmed it as a pandemic on March 11, 2020. In the Middle East, Iran was the first country where the SARS-Cov-2 was detected. The epidemiological and economic challenges of Iran make this country a particularly relevant subject of study. In the current study, we aimed to evaluate the clinical, radiological and laboratory findings in hospitalized COVID-19 confirmed cases in Ilam province, western of Iran.

Methods

Overall, 2204 hospitalized RT-PCR confirmed patients with COVID-19 were considered in this study. Electronic medical records, including clinical symptoms, radiological images, laboratory findings, and the comorbidities of patients with COVID-19 were collected and analyzed. In addition, the medication regimens used in these patients were evaluated. The patients were classified in discharged and died groups according to their outcomes. Then, clinical, radiological and laboratory findings as well as treatment regimens and underlying diseases were compared in these two groups.

Results

Among the patients, 1209 (54.85%) were male and 995 (45.14%) were female. Pneumonia, dyspnea and cough, were the most common clinical data in both discharged and died groups. Among the comorbidities, COPD, and cancer were significantly more common in the dead patients than in the living. The results of laboratory tests showed that blood creatinine, BUN, ESR, Na+, WBC, and neutrophil count have increased in deceased group compared to the survivors. However, the lymphocyte count decreased in deceased patients. The evaluation of radiographs demonstrated that there were significant correlations between bilateral pneumonia, ground glass opacity, bilateral patchy shadowing, and pleural effusion with death.

Conclusion

The current investigation indicated the special profile of COVID-19 in west of Iran. Discharged and dead patients with COVID-19 had distinct clinical, radiological and laboratory features, which were separated by principal component analysis. Identifying these characteristics of the disease would translate into the implementation of practical measures to improve results.

Essentials of COVID-19 and treatment approaches

The coronavirus family is as old as the 1930s when it first showed symptoms in chicken. The virus thereafter kept evolving and it has significantly taken over a large percentage of people worldwide in the form of this new pandemic. As of the present day, there is no treatment available for coronavirus disease 2019 (COVID-19) (caused by the severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]), although supportive therapy and preventive measures have shown a tremendous control rate among certain patients. Drugs like remdesivir, camostat, nafamostat, ritonavir/lopinavir, several monoclonal antibodies, and CPs are in their early phases of trials. There are approved by the WHO under an emergency use authorization program. Favipiravir has entered its phase 3 clinical trial and is supported by evidence to show no or less adverse effects in patients infected with SARS-CoV-2. Vaccine development is accelerating its pace, and vaccines will probably become available by the end of the year 2020.

Interplay of Nutrition and Psychoneuroendocrineimmune Modulation: Relevance for COVID-19 in BRICS Nations

The consequences of COVID-19 are not limited to physical health deterioration; the impact on neuropsychological well-being is also substantially reported. The inter-regulation of physical health and psychological well-being through the psychoneuroendocrineimmune (PNEI) axis has enduring consequences in susceptibility, treatment outcome as well as recuperation. The pandemic effects are upsetting the lifestyle, social interaction, and financial security; and also pose a threat through perceived fear. These consequences of COVID-19 also influence the PNEI system and wreck the prognosis. The nutritional status of individuals is also reported to have a determinative role in COVID-19 severity and convalescence. In addition to energetic demand, diet also provides precursor substances [amino acids (AAs), vitamins, etc.] for regulators of the PNEI axis such as neurotransmitters (NTs) and immunomodulators. Moreover, exaggerated immune response and recovery phase of COVID-19 demand additional nutrient intake; widening the gap of pre-existing undernourishment. Mushrooms, fresh fruits and vegetables, herbs and spices, and legumes are few of such readily available food ingredients which are rich in protein and also have medicinal benefits. BRICS nations have their influences on global development and are highly impacted by a large number of confirmed COVID-19 cases and deaths. The adequacy and access to healthcare are also low in BRICS nations as compared to the rest of the world. Attempt to combat the COVID-19 pandemic are praiseworthy in BRICS nations. However, large population sizes, high prevalence of undernourishment (PoU), and high incidence of mental health ailments in BRICS nations provide a suitable landscape for jeopardy of COVID-19. Therefore, appraising the interplay of nutrition and PNEI modulation especially in BRICS countries will provide better understanding; and will aid in combat COVID-19. It can be suggested that the monitoring will assist in designing adjunctive interventions through medical nutrition therapy and psychopsychiatric management.

Repurposing old molecules for new indications: Defining pillars of success from lessons in the past

Drug repurposing or studying existing drugs for potential therapeutic utility in newer indications has been identified as an attractive option for treating a number of diseases. Various strategies of drug repurposing include serendipitous observation of drug's unexpected effects, directing the failed investigational drugs to new indications and currently adopted systematic approach to identify, screen and develop existing drug molecules for new off-label indications. Drug repurposing is able to constructively overcome the bottleneck restraints encountered during traditional de novo drug development process in grounds of timelines, cost and resources. However, success rates of drug repurposing programs are not very impressive. Through a meticulous examination of some failed repurposing attempts we aimed to identify key factors leading to high attrition rate in such studies. Based on the fundamental elements of knowledge and evaluation, we have defined four pillars toward improving success rate in drug repurposing programs viz. sound knowledge of the repurposed drug's pharmacological characteristics (pillar 1: drug pharmacology); drug formulation considerations in new indication (pillar 2: drug formulation); evaluation in representative biological assays with translational potential (pillar 3: evaluation in biological assays); and robust clinical trial methodologies including biomarker driven approach to provide conclusive evidence of repurposed drug's efficacy in new indication (pillar 4: clinical evaluation). In addition to the pharmacological challenges, certain regulatory concerns, including lack of clear guidelines for evaluation and market exclusivity pose hurdles in the application of drug repurposing, which may however be overcome to a great extent by adopting some strategies as discussed in this review.

Clinical efficacy and safety of interferon-β-containing regimens in the treatment of patients with COVID-19: a systematic review and meta-analysis of randomized controlled trials

OBJECTIVE

The aim of this systematic review and meta-analysis of randomized controlled trials(RCTs) was to investigate the efficacy of interferon (IFN)-β-containing regimens in treating patients with COVID-19.

METHODS

PubMed, Embase, Cochrane Central Register of Controlled Trials, and ClinicalTrials.gov were searched from inception to 17 July 2021. RCTs comparing the clinical efficacy and safety of IFN-β-containing regimens (study group) to other antiviral treatment options or placebo (control group) in treating patients with COVID-19 were included.

RESULTS

Eight RCTs were included. No significant difference in the 28-day all-cause mortality rate was observed between the study and control groups (OR, 0.74; 95% CI, 0.44-1.24; I² = 51%). The study groups had a lower rate of intensive care unit (ICU) admissions than the control groups (OR 0.58, 95% CI 0.36-0.95; I² = 0%). Furthermore, INF-β was not associated with an increased risk of any adverse event (AE) or serious AE when compared with the control group.

CONCLUSIONS

IFN-β does not appear to provide an increased survival benefit in hospitalized patients with COVID-19 but may help reduce the risk of ICU admission. Moreover, IFN-β is a safe agent for use in the treatment of COVID-19.

Innate Immunity Evasion Strategies of Highly Pathogenic Coronaviruses: SARS-CoV, MERS-CoV, and SARS-CoV-2

In the past two decades, coronavirus (CoV) has emerged frequently in the population. Three CoVs (SARS-CoV, MERS-CoV, SARS-CoV-2) have been identified as highly pathogenic human coronaviruses (HP-hCoVs). Particularly, the ongoing COVID-19 pandemic caused by SARS-CoV-2 warns that HP-hCoVs present a high risk to human health. Like other viruses, HP-hCoVs interact with their host cells in sophisticated manners for infection and pathogenesis. Here, we reviewed the current knowledge about the interference of HP-hCoVs in multiple cellular processes and their impacts on viral infection. HP-hCoVs employed various strategies to suppress and evade from immune response, including shielding viral RNA from recognition by pattern recognition receptors (PRRs), impairing IFN-I production, blocking the downstream pathways of IFN-I, and other evasion strategies. This summary provides a comprehensive view of the interplay between HP-hCoVs and the host cells, which is helpful to understand the mechanism of viral pathogenesis and develop antiviral therapies.

Coronavirus induces diabetic macrophage-mediated inflammation via SETDB2

The COVID-19 pandemic has disproportionately affected patients with comorbidities, namely, obesity and type 2 diabetes. Macrophages (Mφs) are a key innate immune cell primarily responsible for the harmful, hyperinflammatory “cytokine storm” in patients that develop severe COVID-19. We describe a mechanism for this Mφ-mediated cytokine storm in response to coronavirus. In response to coronavirus infection, expression of the chromatin-modifying enzyme, SETDB2, decreases in Mφs, leading to increased transcription of inflammatory cytokines. Further, we find SETDB2 is regulated by an interferon beta (IFNβ)/JaK/STAT3 mechanism, and that exogenous administration of IFNβ can reverse inflammation, particularly in diabetic Mφs via an increase in SETDB2. Together, these results suggest therapeutic targeting of the IFNβ/SETDB2 axis in diabetic patients with COVID-19 may decrease pathologic inflammation.

COVID-19 induces a robust, extended inflammatory “cytokine storm” that contributes to an increased morbidity and mortality, particularly in patients with type 2 diabetes (T2D). Macrophages are a key innate immune cell population responsible for the cytokine storm that has been shown, in T2D, to promote excess inflammation in response to infection. Using peripheral monocytes and sera from human patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), and a murine hepatitis coronavirus (MHV-A59) (an established murine model of SARS), we identified that coronavirus induces an increased Mφ-mediated inflammatory response due to a coronavirus-induced decrease in the histone methyltransferase, SETDB2. This decrease in SETDB2 upon coronavirus infection results in a decrease of the repressive trimethylation of histone 3 lysine 9 (H3K9me3) at NFkB binding sites on inflammatory gene promoters, effectively increasing inflammation. Mφs isolated from mice with a myeloid-specific deletion of SETDB2 displayed increased pathologic inflammation following coronavirus infection. Further, IFNβ directly regulates SETDB2 in Mφs via JaK1/STAT3 signaling, as blockade of this pathway altered SETDB2 and the inflammatory response to coronavirus infection. Importantly, we also found that loss of SETDB2 mediates an increased inflammatory response in diabetic Mϕs in response to coronavirus infection. Treatment of coronavirus-infected diabetic Mφs with IFNβ reversed the inflammatory cytokine production via up-regulation of SETDB2/H3K9me3 on inflammatory gene promoters. Together, these results describe a potential mechanism for the increased Mφ-mediated cytokine storm in patients with T2D in response to COVID-19 and suggest that therapeutic targeting of the IFNβ/SETDB2 axis in T2D patients may decrease pathologic inflammation associated with COVID-19.

The role of type I interferon in the treatment of COVID-19

Although significant research has been done to find effective drugs against coronavirus disease 2019 (COVID‐19) caused by severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), no definite effective drug exists. Thus, research has now shifted towards immunomodulatory agents other than antivirals. In this review, we aim to describe the latest findings on the role of type I interferon (IFN)‐mediated innate antiviral response against SARS‐CoV‐2 and discuss the use of IFNs as a medication for COVID‐19. A growing body of evidence has indicated a promoting active but delayed IFNs response to SARS‐CoV‐2 and Middle East respiratory syndrome coronavirus in infected bronchial epithelial cells. Studies have demonstrated that IFNs' administration before the viral peak and the inflammatory phase of disease could offer a highly protective effect. However, IFNs' treatment during the inflammatory and severe stages of the disease causes immunopathology and long‐lasting harm for patients. Therefore, it is critical to note the best time window for IFNs' administration. Further investigation of the clinical effectiveness of interferon for patients with mild to severe COVID‐19 and its optimal timing and route of administration can be beneficial in finding a safe and effective antiviral therapy for the COVID‐19 disease.

1‐IFNs have many antiviral actions including; the activation of cytotoxic T‐cell responses, the inhibition of the viral mRNA translation, the degradation of the viral RNA, RNA editing and modulating the synthesis of Nitric Oxide.

2‐IFNS are two‐edged immunomodulatory agents; as they can provide a protective effect if administered in the early phases of the disease before the viral peak, whereas a harming effect is observed when administered in the inflammatory phase.

3‐More human trials are needed to find the best time window for administrating type I IFN for patients with various COVID‐19 modalities.

Type I Interferons in COVID-19 Pathogenesis

Among the many activities attributed to the type I interferon (IFN) multigene family, their roles as mediators of the antiviral immune response have emerged as important components of the host response to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection. Viruses likewise have evolved multiple immune evasion strategies to circumvent the host immune response and promote virus propagation and dissemination. Therefore, a thorough characterization of host-virus interactions is essential to understand SARS-CoV-2 pathogenesis. Here, we summarize the virus-mediated evasion of the IFN responses and the viral functions involved, the genetic basis of IFN production in SARS-CoV-2 infection and the progress of clinical trials designed to utilize type I IFN as a potential therapeutic tool.

Immune response to SARS-CoV-2 in children: A review of the current knowledge

Host immune responses to severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2), especially in children, are still under investigation. Children with coronavirus disease 2019 (COVID‐19) constitute a significant study group of immune responses as they rarely present with severe clinical manifestations, require hospitalization, or develop complications such as multisystem inflammatory syndrome in children (MIS‐C) associated with SARS‐CoV‐2 infection. The deciphering of children’s immune responses during COVID‐19 infection will provide information about the protective mechanisms, while new potential targets for future therapies are likely to be revealed. Despite the limited immunological studies in children with COVID‐19, this review compares data between adults and children in terms of innate and adaptive immunity to SARS‐CoV‐2, discusses the possible reasons why children are mostly asymptomatic, and highlights unanswered or unclear immunological issues. Current evidence suggests that the activity of innate immunity seems to be crucial to the early phases of SARS‐CoV‐2 infection and adaptive memory immunity is vital to prevent reinfection.

Despite the limited immunological studies from children with COVID‐19, this review compares data between adults and children in terms of innate and adaptive immunity to SARS‐CoV‐2, discusses the possible reasons why children are mostly asymptomatic, and highlights unanswered or unclear immunological issues.

COVID-19: Failure of the DisCoVeRy Clinical Trial, and Now-New Hopes?

The DisCoVeRy clinical trial aimed at the evaluation of four treatments for patients suffering from severe to critical COVID-19: Hydroxychloroquine, eventually associated with azithromycin; the combination lopinavir/ritonavir; the combination with the addition of interferon β-1a; remdesivir. The trial was discontinued due to the lack of positive results. Meanwhile, many other potential options have been considered either to target the virus itself, the interactions with the host cells, or the cytokine storm frequently observed during the infection. Several of those options are briefly reviewed. They include vaccines, small molecules, antibodies, and stem cells.

Controversies’ clarification regarding ribavirin efficacy in measles and coronaviruses: Comprehensive therapeutic approach strictly tailored to COVID-19 disease stages

BACKGROUND

Ribavirin is a broad-spectrum nucleoside antiviral drug with multimodal mechanisms of action, which supports its longevity and quality as a clinical resource. It has been widely administered for measles and coronavirus infections. Despite the large amount of data concerning the use of ribavirin alone or in combination for measles, severe acute respiratory syndrome, Middle East respiratory syndrome, and coronavirus disease 2019 (COVID-19) outbreaks, the conclusions of these studies have been contradictory. Underlying reasons for these discrepancies include possible study design inaccuracies and failures and misinterpretations of data, and these potential confounds should be addressed.

AIM

To determine the confounding factors of ribavirin treatment studies and propose a therapeutic scheme for COVID-19.

METHODS

PubMed database was searched over a period of five decades utilizing the terms “ribavirin” alone or combined with other compounds in measles, severe acute respiratory syndrome, Middle East respiratory syndrome, and COVID-19 infections. The literature search was performed and described according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Articles were considered eligible when they reported on ribavirin dose regimens and/or specified outcomes concerning its efficacy and/or possible adverse-effects. In vitro and animal studies were also retrieved. A chapter on ribavirin’s pharmacology was included as well.

RESULTS

In addition to the difficulties and pressures of an emerging pandemic, there is the burden of designing and conducting well-organized, double-blind, randomized controlled trials. Many studies have succumbed to specific pitfalls, one of which was identified in naturally ribavirin-resistant Vero cell lines in in vitro studies. Other pitfalls include study design inconsistent with the well-established clinical course of disease; inappropriate pharmacology of applied treatments; and the misinterpretation of study results with misconceived generalizations. A comprehensive treatment for COVID-19 is proposed, documented by thorough, long-term investigation of ribavirin regimens in coronavirus infections.

CONCLUSION

A comprehensive treatment strictly tailored to distinct disease stages was proposed based upon studies on ribavirin and coronavirus infections.

Review: The Nose as a Route for Therapy. Part 2 Immunotherapy

The nose provides a route of access to the body for inhalants and fluids. Unsurprisingly it has a strong immune defense system, with involvement of innate (e.g., epithelial barrier, muco- ciliary clearance, nasal secretions with interferons, lysozyme, nitric oxide) and acquired (e.g., secreted immunoglobulins, lymphocytes) arms. The lattice network of dendritic cells surrounding the nostrils allows rapid uptake and sampling of molecules able to negotiate the epithelial barrier. Despite this many respiratory infections, including SARS-CoV2, are initiated through nasal mucosal contact, and the nasal mucosa is a significant "reservoir" for microbes including Streptococcus pneumoniae, Neisseria meningitidis and SARS -CoV-2. This review includes consideration of the augmentation of immune defense by the nasal application of interferons, then the reduction of unnecessary inflammation and infection by alteration of the nasal microbiome. The nasal mucosa and associated lymphoid tissue (nasopharynx-associated lymphoid tissue, NALT) provides an important site for vaccine delivery, with cold-adapted live influenza strains (LAIV), which replicate intranasally, resulting in an immune response without significant clinical symptoms, being the most successful thus far. Finally, the clever intranasal application of antibodies bispecific for allergens and Intercellular Adhesion Molecule 1 (ICAM-1) as a topical treatment for allergic and RV-induced rhinitis is explained.

An investigation into the beneficial effects of high-dose interferon beta 1-a, compared to low-dose interferon beta 1-a in severe COVID-19: The COVIFERON II randomized controlled trial

Introduction

Coronavirus disease 2019 (COVID-19) has been a serious obstacle in front of public health. Interferon-beta 1a (IFN-β 1a) has been used to treat patients with COVID-19. We aimed to compare the effectiveness of high-dose IFN-β 1a compared to low dose IFN-β 1a in severe COVID-19 cases.

Methods

In this randomized, controlled, and clinical trial, eligible patients with confirmed SARS-CoV-2 infections were randomly assigned to receive one of the two following therapeutic regimens: The intervention group was treated with high-dose IFN-β 1a (Recigen) (Subcutaneous injections of 88 μg (24 million IU) on days 1, 3, 6) + lopinavir /ritonavir (Kaletra) (400 mg/100 mg twice a day for 10 days, orally) and the control group was treated with low-dose IFN-β 1a (Recigen) (Subcutaneous injections of 44 μg (12 million IU) on days 1, 3, 6) + lopinavir /ritonavir (Kaletra) (400 mg/100 mg twice a day for 10 days, orally).

Result

A total of 168 COVID- 19 confirmed patients underwent randomization; 83 were assigned to the intervention group and 85 were assigned to the control group. Median Time To Clinical Improvement (TTIC) for cases treated with low-dose IFN-β1a was shorter than that for cases treated with high-dose IFN-β1a (6 vs 10 days; P = 0.018). The mortality rates in intervention and control group were 41% and 36.5%, respectively.

Conclusion

The use of high-dose IFN-β 1a did not improve TTCI in hospitalized patients with moderate to severe COVID-19. Also, it did not have any significant effect on mortality reduction compared with treating with low-dose IFN-β 1a.

Trial registration: This trial has been registered as ClinicalTrials.gov, NCT04521400.

Control of Innate Immune Activation by Severe Acute Respiratory Syndrome Coronavirus 2 and Other Coronaviruses

The ongoing coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), represents a public health crisis of unprecedented proportions. After the emergence of SARS-CoV-1 in 2002, and Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012, this is the third outbreak of a highly pathogenic zoonotic coronavirus (CoV) that the world has witnessed in the last 2 decades. Infection with highly pathogenic human CoVs often results in a severe respiratory disease characterized by a delayed and blunted interferon (IFN) response, accompanied by an excessive production of proinflammatory cytokines. This indicates that CoVs developed effective mechanisms to overcome the host innate immune response and promote viral replication and pathogenesis. In this review, we describe the key innate immune signaling pathways that are activated during infection with SARS-CoV-2 and other well studied pathogenic CoVs. In addition, we summarize the main strategies that these viruses employ to modulate the host immune responses through the antagonism of IFN induction and effector pathways.

Exploring the therapeutic potential of forkhead box O for outfoxing COVID-19

The COVID-19 pandemic has wreaked unprecedented societal havoc worldwide. The infected individuals may present mild to severe symptoms, with nearly 20% of the confirmed patients impaired with significant complications, including multi-organ failure. Acute respiratory distress imposed by SARS-CoV-2 largely results from an aggravated cytokine storm and deregulated immune response. The forkhead box O (FoxO) transcription factors are reported to play a significant role in maintaining normal cell physiology by regulating survival, apoptosis, oxidative stress, development and maturation of T and B lymphocytes, secretion of inflammatory cytokines, etc. We propose a potent anti-inflammatory approach based on activation of the FoxO as an attractive strategy against the novel coronavirus. This regime will be focused on restoring redox and inflammatory homeostasis along with repair of the damaged tissue, activation of lymphocyte effector and memory cells. Repurposing FoxO activators as a means to alleviate the inflammatory burst following SARS-CoV-2 infection can prove immensely valuable in the ongoing pandemic and provide a reliable groundwork for enriching our repertoire of antiviral modalities for any such complication in the future. Altogether, our review highlights the possible efficacy of FoxO activation as a novel arsenal for clinical management of COVID-19.

Roles of Type I and III Interferons in COVID-19

Coronavirus disease 2019 (COVID-19) is an ongoing global pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Type I and III interferon (IFN) responses act as the first line of defense against viral infection and are activated by the recognition of viruses by infected cells and innate immune cells. Dysregulation of host IFN responses has been known to be associated with severe disease progression in COVID-19 patients. However, the reported results are controversial and the roles of IFN responses in COVID-19 need to be investigated further. In the absence of a highly efficacious antiviral drug, clinical studies have evaluated recombinant type I and III IFNs, as they have been successfully used for the treatment of infections caused by two other epidemic coronaviruses, SARS-CoV-1 and Middle East respiratory syndrome (MERS)-CoV. In this review, we describe the strategies by which SARS-CoV-2 evades IFN responses and the dysregulation of host IFN responses in COVID-19 patients. In addition, we discuss the therapeutic potential of type I and III IFNs in COVID-19.

Disease-drug and drug-drug interaction in COVID-19: Risk and assessment

COVID-19 is announced as a global pandemic in 2020. Its mortality and morbidity rate are rapidly increasing, with limited medications. The emergent outbreak of COVID-19 prompted by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) keeps spreading. In this infection, a patient's immune response plays pivotal role in the pathogenesis. This inflammatory factor was shown by its mediators that, in severe cases, reach the cytokine at peaks. Hyperinflammatory state may sparks significant imbalances in transporters and drug metabolic machinery, and subsequent alteration of drug pharmacokinetics may result in unexpected therapeutic response. The present scenario has accounted for the requirement for therapeutic opportunities to relive and overcome this pandemic. Despite the diminishing developments of COVID-19, there is no drug still approved to have significant effects with no side effect on the treatment for COVID-19 patients. Based on the evidence, many antiviral and anti-inflammatory drugs have been authorized by the Food and Drug Administration (FDA) to treat the COVID-19 patients even though not knowing the possible drug-drug interactions (DDI). Remdesivir, favipiravir, and molnupiravir are deemed the most hopeful antiviral agents by improving infected patient’s health. Dexamethasone is the first known steroid medicine that saved the lives of seriously ill patients. Some oligopeptides and proteins have also been using. The current review summarizes medication updates to treat COVID-19 patients in an inflammatory state and their interaction with drug transporters and drug-metabolizing enzymes. It gives an opinion on the potential DDI that may permit the individualization of these drugs, thereby enhancing the safety and efficacy.

Role of interferon therapy in severe COVID-19: the COVIFERON randomized controlled trial

Type 1 Interferons (IFNs) have been associated with positive effects on Coronaviruses. Previous studies point towards the superior potency of IFNβ compared to IFNα against viral infections. We conducted a three-armed, individually-randomized, open-label, controlled trial of IFNβ1a and IFNβ1b, comparing them against each other and a control group. Patients were randomly assigned in a 1:1:1 ratio to IFNβ1a (subcutaneous injections of 12,000 IU on days 1, 3, 6), IFNβ1b (subcutaneous injections of 8,000,000 IU on days 1, 3, 6), or the control group. All three arms orally received Lopinavir/Ritonavir (400 mg/100 mg twice a day for ten days) and a single dose of Hydroxychloroquine 400 mg on the first day. Our utilized primary outcome measure was Time To Clinical Improvement (TTCI) defined as the time from enrollment to discharge or a decline of two steps on the clinical seven-step ordinal scale, whichsoever came first. A total of 60 severely ill patients with positive RT-PCR and Chest CT scans underwent randomization (20 patients to each arm). In the Intention-To-Treat population, IFNβ1a was associated with a significant difference against the control group, in the TTCI; (HR; 2.36, 95% CI 1.10–5.17, P-value = 0.031) while the IFNβ1b indicated no significant difference compared with the control; HR; 1.42, (95% CI 0.63–3.16, P-value = 0.395). The median TTCI for both of the intervention groups was five days vs. seven days for the control group. The mortality was numerically lower in both of the intervention groups (20% in the IFNβ1a group and 30% in the IFNβ1b group vs. 45% in the control group). There were no significant differences between the three arms regarding the adverse events. In patients with laboratory-confirmed SARS-CoV-2 infection, as compared with the base therapeutic regiment, the benefit of a significant reduction in TTCI was observed in the IFNβ1a arm. This finding needs further confirmation in larger studies.

Trial Registration Number: ClinicalTrials.gov, NCT04343768. (Submitted: 08/04/2020; First Online: 13/04/2020) (Registration Number: NCT04343768).

SAveRUNNER: an R-based tool for drug repurposing

BACKGROUND

Currently, no proven effective drugs for the novel coronavirus disease COVID-19 exist and despite widespread vaccination campaigns, we are far short from herd immunity. The number of people who are still vulnerable to the virus is too high to hamper new outbreaks, leading a compelling need to find new therapeutic options devoted to combat SARS-CoV-2 infection. Drug repurposing represents an effective drug discovery strategy from existing drugs that could shorten the time and reduce the cost compared to de novo drug discovery.

RESULTS

We developed a network-based tool for drug repurposing provided as a freely available R-code, called SAveRUNNER (Searching off-lAbel dRUg aNd NEtwoRk), with the aim to offer a promising framework to efficiently detect putative novel indications for currently marketed drugs against diseases of interest. SAveRUNNER predicts drug-disease associations by quantifying the interplay between the drug targets and the disease-associated proteins in the human interactome through the computation of a novel network-based similarity measure, which prioritizes associations between drugs and diseases located in the same network neighborhoods.

CONCLUSIONS

The algorithm was successfully applied to predict off-label drugs to be repositioned against the new human coronavirus (2019-nCoV/SARS-CoV-2), and it achieved a high accuracy in the identification of well-known drug indications, thus revealing itself as a powerful tool to rapidly detect potential novel medical indications for various drugs that are worth of further investigation. SAveRUNNER source code is freely available at https://github.com/giuliafiscon/SAveRUNNER.git , along with a comprehensive user guide.

Experimental therapies under investigation for COVID-19

Coronavirus Disease 2019, caused by the virus, Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2), is a pandemic first discovered in Wuhan, China which has claimed over 1.7 million lives to date across the globe as of 24 December 2020. As the virus spreads across the world affecting millions of patients, there has been a massive movement to discover readily available and effective treatment options including vaccines. One of the limiting factors in treating the disease is its varied presentation and effect in patients, ranging from asymptomatic patients to those left in intensive care units, intubated and fighting for their lives. There are numerous clinical trials and small-scale studies underway to investigate potential treatment options. However, very few studies and drugs demonstrated efficacy while many more are under investigation, leaving care teams dependent on supportive care coupled with experimental treatment options. In this review, we summarize the various treatment options explored to treat COVID-19, discussing possible the mechanisms of fighting the virus.

Serum Protein Profiling Reveals a Specific Upregulation of the Immunomodulatory Protein Progranulin in Coronavirus Disease 2019

Background

Severe courses of COVID-19 are associated with elevated levels of interleukin 6. However, there is a growing body of evidence pointing to a broad and more complex disorder of pro-inflammatory and anti-viral responses with disturbed interferon signaling in COVID-19.

Methods

In this prospective single-center registry, we included SARS-CoV-2 positive patients and patients with similar symptoms and severity of disease but negative for SARS-CoV-2 admitted to the emergency department and compared their serum protein expression profiles.

Results

Interleukin-6 abundance was similar in SARS-CoV-2 positive patients (n = 24) compared to SARS-CoV-2 negative control (n = 61). In contrast, we observed a specific upregulation of the immunomodulatory protein progranulin (GRN). High GRN abundance was associated with adverse outcomes and increased expression of interleukin-6 in COVID-19.

Conclusion

The data from this registry reveals that GRN is specifically upregulated in SARS-CoV-2 positive patients while interleukin-6 may serve as marker for disease severity. The potential of GRN as a biomarker and a possible impact of increased GRN expression on interferon signaling, virus elimination, and virus-induced lung tissue damage in COVID-19 should be further explored.

Efficacy of ribavirin and interferon-α therapy for hospitalized patients with COVID-19: A multicenter, retrospective cohort study

OBJECTIVE

To assess the efficacy and safety of ribavirin and interferon-α (RBV/IFN-α) therapy in COVID-19 patients.

METHODS

A multicenter, retrospective cohort study of COVID-19 patients admitted to 4 hospitals in Hubei Province, China, from 31 December 2019 to 31 March 2020. Patients were divided into 2 groups according to their exposure to RBV/IFN-α therapy within 48 h of admission. Mixed-effect Cox model and Logistic regression were used to explore the association between early treatments of RBV/IFN-α and primary outcomes.

RESULTS

Of 2037 patients included, 1281 received RBV/IFN-α (RBV, IFN-α or RBV combined with IFN-α) treatments and 756 received none of these treatments. In a mixed effect model, RBV/IFN-α therapy was not associated with progression from non-severe into severe type (adjusted hazard ratio (aHR) = 1.09, 95% CI: 0.88-1.36) or with reduction in 30-day mortality (aHR = 0.89, 95% CI: 0.61-1.30). However, it was associated with a higher probability of hospital stay >15 days (adjusted odds ratio (aOR) = 2.11, 95% CI: 1.68-2.64) compared with no RBV/IFN-α therapy. The propensity score-matched cohort and subgroup analysis displayed similar results.

CONCLUSION

RBV/IFN-α therapy was not observed to improve clinical outcomes in COVID-19 patients suggesting that RBV/IFN-α therapy should be avoided in COVID-19 treatment.

The COVID-19 Treatment Landscape: A South African Perspective on a Race Against Time

The pandemic caused by SARS-CoV-2 has infected more than 94 million people worldwide (as of 17 January 2020). Severe disease is believed to be secondary to the cytokine release syndrome (CRS or "cytokine storm") which causes local tissue damage as well as multi-organ dysfunction and thrombotic complications. Due to the high mortality rates in patients receiving invasive ventilation, practice has changed from "early-intubation" for acute respiratory distress syndrome (ARDS) to a trial of non-invasive ventilation (NIV) or high flow nasal cannula (HFNC) oxygen. Reports indicating the benefit of NIV and HFNC have been encouraging and have led to more than 20,000 such devices being manufactured and ready for roll-out in South Africa (SA) as of July 2020. The need to identify drugs with clear clinical benefits has led to an array of clinical trials, most of which are repurposing drugs for COVID-19. The treatment landscape reflects the need to target both the virus and its effects such as the CRS and thrombotic complications. Conflicting results have the potential to confuse the implementation of coordinated treatment strategies and guidelines. The purpose of this review is to address pertinent areas in the current literature on the available medical treatment options for COVID-19. Remdesivir, tocilizumab, and dexamethasone are some of the treatment options that have shown the most promise, but further randomized trials are required to particularly address timing and dosages to confidently create standardized protocols. For the SA population, two healthcare sectors exist. In the private sector, patients with medical insurance may have greater access to a wider range of treatment options than those in the public sector. The latter serves >80% of the population, and resource constraints require the identification of drugs with the most cost-effective use for the greatest number of affected patients.

SAveRUNNER: A network-based algorithm for drug repurposing and its application to COVID-19

The novelty of new human coronavirus COVID-19/SARS-CoV-2 and the lack of effective drugs and vaccines gave rise to a wide variety of strategies employed to fight this worldwide pandemic. Many of these strategies rely on the repositioning of existing drugs that could shorten the time and reduce the cost compared to de novo drug discovery. In this study, we presented a new network-based algorithm for drug repositioning, called SAveRUNNER (Searching off-lAbel dRUg aNd NEtwoRk), which predicts drug-disease associations by quantifying the interplay between the drug targets and the disease-specific proteins in the human interactome via a novel network-based similarity measure that prioritizes associations between drugs and diseases locating in the same network neighborhoods. Specifically, we applied SAveRUNNER on a panel of 14 selected diseases with a consolidated knowledge about their disease-causing genes and that have been found to be related to COVID-19 for genetic similarity (i.e., SARS), comorbidity (e.g., cardiovascular diseases), or for their association to drugs tentatively repurposed to treat COVID-19 (e.g., malaria, HIV, rheumatoid arthritis). Focusing specifically on SARS subnetwork, we identified 282 repurposable drugs, including some the most rumored off-label drugs for COVID-19 treatments (e.g., chloroquine, hydroxychloroquine, tocilizumab, heparin), as well as a new combination therapy of 5 drugs (hydroxychloroquine, chloroquine, lopinavir, ritonavir, remdesivir), actually used in clinical practice. Furthermore, to maximize the efficiency of putative downstream validation experiments, we prioritized 24 potential anti-SARS-CoV repurposable drugs based on their network-based similarity values. These top-ranked drugs include ACE-inhibitors, monoclonal antibodies (e.g., anti-IFNγ, anti-TNFα, anti-IL12, anti-IL1β, anti-IL6), and thrombin inhibitors. Finally, our findings were in-silico validated by performing a gene set enrichment analysis, which confirmed that most of the network-predicted repurposable drugs may have a potential treatment effect against human coronavirus infections.

Vitamin D, zinc and glutamine: Synergistic action with OncoTherad immunomodulator in interferon signaling and COVID‑19 (Review)

Coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was identified in December, 2019 in Wuhan, China. Since then, it has continued to spread rapidly in numerous countries, while the search for effective therapeutic options persists. Coronaviruses, including SARS-CoV-2, are known to suppress and evade the antiviral responses of the host organism mediated by interferon (IFN), a family of cytokines that plays an important role in antiviral defenses associated with innate immunity, and has been used therapeutically for chronic viral diseases and cancer. On the other hand, OncoTherad, a safe and effective immunotherapeutic agent in the treatment of non-muscle invasive bladder cancer (NMIBC), increases IFN signaling and has been shown to be a promising therapeutic approach for COVID-19 in a case report that described the rapid recovery of a 78-year-old patient with NMIBC with comorbidities. The present review discusses the possible synergistic action of OncoTherad with vitamin D, zinc and glutamine, nutrients that have been shown to facilitate immune responses mediated by IFN signaling, as well as the potential of this combination as a therapeutic option for COVID-19.

Pharmacokinetics under the COVID-19 storm

AIMS

The storm-like nature of the health crises caused by COVID-19 has led to unconventional clinical trial practices such as the relaxation of exclusion criteria. The question remains: how can we conduct diverse trials without exposing subgroups of populations to potentially harmful drug exposure levels? The aim of this study was to build a knowledge base of the effect of intrinsic/extrinsic factors on the disposition of several repurposed COVID-19 drugs.

METHODS

Physiologically based pharmacokinetic (PBPK) models were used to study the change in the pharmacokinetics (PK) of drugs repurposed for COVID-19 in geriatric patients, different race groups, organ impairment and drug-drug interactions (DDIs) risks. These models were also used to predict epithelial lining fluid (ELF) exposure, which is relevant for COVID-19 patients under elevated cytokine levels.

RESULTS

The simulated PK profiles suggest no dose adjustments are required based on age and race for COVID-19 drugs, but dose adjustments may be warranted for COVID-19 patients also exhibiting hepatic/renal impairment. PBPK model simulations suggest ELF exposure to attain a target concentration was adequate for most drugs, except for hydroxychloroquine, azithromycin, atazanavir and lopinavir/ritonavir.

CONCLUSION

We demonstrate that systematically collated data on absorption, distribution, metabolism and excretion, human PK parameters, DDIs and organ impairment can be used to verify simulated plasma and lung tissue exposure for drugs repurposed for COVID-19, justifying broader patient recruitment criteria. In addition, the PBPK model developed was used to study the effect of age and ethnicity on the PK of repurposed drugs, and to assess the correlation between lung exposure and relevant potency values from in vitro studies for SARS-CoV-2.

Treatment of severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and coronavirus disease 2019 (COVID-19): a systematic review of in vitro, in vivo, and clinical trials

Rationale: Coronavirus disease 2019 (COVID-19) has spread worldwide and poses a threat to humanity. However, no specific therapy has been established for this disease yet. We conducted a systematic review to highlight therapeutic agents that might be effective in treating COVID-19. Methods: We searched Medline, Medrxiv.org, and reference lists of relevant publications to identify articles of in vitro, in vivo, and clinical studies on treatments for severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and COVID-19 published in English until the last update on October 11, 2020. Results: We included 36 studies on SARS, 30 studies on MERS, and 10 meta-analyses on SARS and MERS in this study. Through 12,200 title and 830 full-text screenings for COVID-19, eight in vitro studies, 46 randomized controlled trials (RCTs) on 6,886 patients, and 29 meta-analyses were obtained and investigated. There was no therapeutic agent that consistently resulted in positive outcomes across SARS, MERS, and COVID-19. Remdesivir showed a therapeutic effect for COVID-19 in two RCTs involving the largest number of total participants (n = 1,461). Other therapies that showed an effect in at least two RCTs for COVID-19 were sofosbuvir/daclatasvir (n = 114), colchicine (n = 140), IFN-β1b (n = 193), and convalescent plasma therapy (n = 126). Conclusions: This review provides information to help establish treatment and research directions for COVID-19 based on currently available evidence. Further RCTs are required.

Potential role of interferons in treating COVID-19 patients

The recently public health crises in the world is emerged by spreading the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) also named COVID-19. The virus is originated in bats and transported to humans via undefined intermediate animals. This virus can produce from weak to severe respiratory diseases including acute respiratory distress syndrome (ARDS), multiple organ dysfunction syndrome (MODS), pneumonia and even death in patients. The COVID-19 disease is distributed by inhalation via contaminated droplets or contact with infected environment. The incubation time is from 2 to 14 day and the symptoms are typically fever, sore throat, cough, malaise, fatigue, breathlessness among others. It needs to be considered that many infected people are asymptomatic. Developing various immunological and virological methods to diagnose this disease is supported by several laboratories. Treatment is principally supportive; however, there are several agents that are using in treating of COVID-19 patients. Interferons (IFNs) have shown to be crucial in fighting with COVID-19 disease and can be a suitable candidate in treatment of these patients. Combination therapy can be more effective than monotherapy to cure this disease. Prevention necessitates to be performed by isolation of suspected people and home quarantine as well as taking care to infected people with mild or strict disease at hospitals. As the outbreak of SARS-CoV-2 has accelerated, developing effective therapy is an urgent requirement to battle the virus and prevent further pandemic. In this manuscript we reviewed available information about SARS-CoV-2 and probable therapies for COVID-19 patients.

Structural Characterization of SARS-CoV-2: Where We Are, and Where We Need to Be

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread in humans in almost every country, causing the disease COVID-19. Since the start of the COVID-19 pandemic, research efforts have been strongly directed towards obtaining a full understanding of the biology of the viral infection, in order to develop a vaccine and therapeutic approaches. In particular, structural studies have allowed to comprehend the molecular basis underlying the role of many of the SARS-CoV-2 proteins, and to make rapid progress towards treatment and preventive therapeutics. Despite the great advances that have been provided by these studies, many knowledge gaps on the biology and molecular basis of SARS-CoV-2 infection still remain. Filling these gaps will be the key to tackle this pandemic, through development of effective treatments and specific vaccination strategies.

Cell-mediated immunity to SARS-CoV-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) viruses spread unscrupulously virtually every corner on the planet in a very quick speed leading to an unprecedented world pandemic of COVID-19 claiming a great many of people's life. Paramount importance has been given to the studies on the virus itself including genomic variation and viron structure, as well as cell entry pathway and tissue residence. Other than that, to learn the main characteristic of host immunity responding to SARS-CoV-2 infection is an eminent task for restraining virus and controlling disease progress. Beside antibody production in response to SARS-CoV-2 infection, host cellular immunity plays an indispensable role in impeding virus replication and expansion at various stages of COVID-19 disease. In this review, we summarized the recent knowledge regarding the aberrant regulation and dysfunction of multiple immune cells during SARS-CoV-2 infection. This includes the dysregulation of immune cell number, Th polarity, cytokine storm they implicated with, as well as cell function exhaustion after chronic virus stimulation. Notwithstanding that many obstacles remain to be overcome, studies on immunotherapy for COVID-19 treatment based on the known features of host immunity in response to SARS-CoV-2 infection offer us tangible benefits and hope for making this SARS-CoV-2 pandemic under control.

Type I IFNs: A Blessing in Disguise or Partner in Crime in MERS-CoV-, SARS-CoV-, and SARS-CoV-2-Induced Pathology and Potential Use of Type I IFNs in Synergism with IFN-γ as a Novel Antiviral Approach Against COVID-19

Since the end of 2019, the emergence of novel coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has accelerated the research on host immune responses toward the coronaviruses. When there is no approved drug or vaccine to use against these culprits, host immunity is the major strategy to fight such infections. Type I interferons are an integral part of the host innate immune system and define one of the first lines of innate immune defense against viral infections. The in vitro antiviral role of type I IFNs against Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV (severe acute respiratory syndrome coronavirus) is well established. Moreover, the involvement of type I IFNs in disease pathology has also been reported. In this study, we have reviewed the protective and the immunopathogenic role of type I IFNs in the pathogenesis of MERS-CoV, SARS-CoV, and SARS-CoV-2. This review will also enlighten the potential implications of type I IFNs for the treatment of COVID-19 when used in combination with IFN-γ.

Could imiquimod (Aldara 5% cream) or other TLR7 agonists be used in the treatment of COVID-19?

Toll-like receptor 7 is critical in recognition of single strand RNA viruses, including SARS CoV-2, and generation of anti-viral immunity. Coronaviruses evolved strategies to dampen the host immunity. Herein, we discuss the potential use of TLR7 agonists in the early stages of COVID-19 treatment.

Interferon β-1b in treatment of severe COVID-19: A randomized clinical trial

In this study, efficacy and safety of interferon (IFN) β-1b in the treatment of patients with severe COVID-19 were evaluated. Among an open-label, randomized clinical trial, adult patients (≥18 years old) with severe COVID-19 were randomly assigned (1:1) to the IFN group or the control group. Patients in the IFN group received IFN β-1b (250 mcg subcutaneously every other day for two consecutive weeks) along with the national protocol medications while in the control group, patients received only the national protocol medications (lopinavir/ritonavir or atazanavir/ritonavir plus hydroxychloroquine for 7-10 days). The primary outcome of the study was time to clinical improvement. Secondary outcomes were in-hospital complications and 28-daymortality. Between April 20 and May 20, 2020, 80 patients were enrolled and finally 33 patients in each group completed the study. Time to clinical improvment in the IFN group was significantly shorter than the control group ([9(6-10) vs. 11(9-15) days respectively, p = 0.002, HR = 2.30; 95% CI: 1.33-3.39]). At day 14, the percentage of discharged patients was 78.79% and 54.55% in the IFN and control groups respectively (OR = 3.09; 95% CI: 1.05-9.11, p = 0.03). ICU admission rate in the control group was significantly higher than the IFN group (66.66% vs. 42.42%, p = 0.04). The duration of hospitalization and ICU stay were not significantly different between the groups All-cause 28-day mortality was 6.06% and 18.18% in the IFN and control groups respectively (p = 0.12). IFN β-1b was effective in shortening the time to clinical improvement without serious adverse events in patients with severe COVID-19. Furthermore, admission in ICU and need for invasive mechanical ventilation decreased following administration of IFN β-1b. Although 28-day mortality was lower in the IFN group, further randomized clinical trials with large sample size are needed for exact estimation of survival benefit of IFN β-1b.

Stopping the COVID-19 Pandemic: A Review on the Advances of Diagnosis, Treatment, and Control Measures

With the continued spread of COVID-19 across the world, rapid diagnostic tools, readily available respurposable drugs, and prompt containment measures to control the SARS-CoV-2 infection are of paramount importance. Examples of recent advances in diagnostic tests are CRISPR technology, IgG assay, spike protein detection, and use of artificial intelligence. The gold standard reverse transcription polymerase chain (RT-PCR) has also been upgraded with point-of-care rapid tests. Supportive treatment, mechanical ventilation, and extracorporeal membrane oxygenation (ECMO) remain the primary choice, while therapeutic options include antivirals, antiparasitics, anti-inflammatories, interferon, convalescent plasma, monoclonal antibody, hyperimmunoglobulin, RNAi, and mesenchymal stem cell therapy. Different types of vaccines such as RNA, DNA, and lentiviral, inactivated, and viral vector are in clinical trials. Moreover, rapidly deployable and easy-to-transport innovative vaccine delivery systems are also in development. As countries have started easing down on the lockdown measures, the chance for a second wave of infection demands strict and rational control policies to keep fatalities minimized. An improved understanding of the advances in diagnostic tools, treatments, vaccines, and control measures for COVID-19 can provide references for further research and aid better containment strategies.

Safety perspectives on presently considered drugs for the treatment of COVID-19

Intense efforts are underway to evaluate potential therapeutic agents for the treatment of COVID-19. In order to respond quickly to the crisis, the repurposing of existing drugs is the primary pharmacological strategy. Despite the urgent clinical need for these therapies, it is imperative to consider potential safety issues. This is important due to the harm-benefit ratios that may be encountered when treating COVID-19, which can depend on the stage of the disease, when therapy is administered and underlying clinical factors in individual patients. Treatments are currently being trialled for a range of scenarios from prophylaxis (where benefit must greatly exceed risk) to severe life-threatening disease (where a degree of potential risk may be tolerated if it is exceeded by the potential benefit). In this perspective, we have reviewed some of the most widely researched repurposed agents in order to identify potential safety considerations using existing information in the context of COVID-19.

COVID-19 Susceptibility in chronic obstructive pulmonary disease

In barely nine months, the pandemic known as COVID-19 has spread over 200 countries, affecting more than 22 million people and causing over than 786 000 deaths. Elderly people and patients with previous comorbidities such as hypertension and diabetes are at an increased risk to suffer a poor prognosis after severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Although the same could be expected from patients with chronic obstructive pulmonary disease (COPD), current epidemiological data are conflicting. This could lead to a reduction of precautionary measures in these patients, in the context of a particularly complex global health crisis. Most COPD patients have a long history of smoking or exposure to other harmful particles or gases, capable of impairing pulmonary defences even years after the absence of exposure. Moreover, COPD is characterized by an ongoing immune dysfunction, which affects both pulmonary and systemic cellular and molecular inflammatory mediators. Consequently, increased susceptibility to viral respiratory infections have been reported in COPD, often worsened by bacterial co-infections and leading to serious clinical outcomes. The present paper is an up-to-date review that discusses the available research regarding the implications of coronavirus infection in COPD. Although validation in large studies is still needed, COPD likely increases SARS-CoV-2 susceptibility and increases COVID-19 severity. Hence, specific mechanisms to monitor and assess COPD patients should be addressed in the current pandemic.

Gut Microbiota Dysbiosis-Immune Hyperresponse-Inflammation Triad in Coronavirus Disease 2019 (COVID-19): Impact of Pharmacological and Nutraceutical Approaches

Coronavirus Disease 2019 (COVID-19) is a pandemic infection caused by a novel coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Patients present a complex clinical picture that, in severe cases, evolves to respiratory, hepatic, gastrointestinal, and neurological complications, and eventually death. The underlying pathophysiological mechanisms are complex and multifactorial and have been summarized as a hyperresponse of the immune system that originates an inflammatory/cytokine storm. In elderly patients, particularly in those with pre-existing cardiovascular, metabolic, renal, and pulmonary disorders, the disease is particularly severe, causing prolonged hospitalization at intensive care units (ICU) and an increased mortality rate. Curiously, the same populations have been described as more prone to a gut microbiota (GM) dysbiosis profile. Intestinal microflora plays a major role in many metabolic and immune functions of the host, including to educate and strengthen the immune system to fight infections, namely of viral origin. Notably, recent studies suggest the existence of GM dysbiosis in COVID-19 patients. This review article highlights the interplay between the triad GM dysbiosis-immune hyperresponse-inflammation in the individual resilience/fragility to SARS-CoV-2 infection and presents the putative impact of pharmacological and nutraceutical approaches on the triumvirate, with focus on GM.