Current utilization of interferon alpha for the treatment of coronavirus disease 2019: A comprehensive review

Pharmacodynamic of Recombinant Human Interferon Alpha-2b Nasal Drops and Effective Prophylaxis Against SARS-COV-2 Infection

The recombinant human interferon alpha-2b (IFN-α2b) nasal drop formulation (Nasalferon) was studied as prophylaxis for SARS-CoV-2. Healthy volunteers between 19 and 80 years of age received 0.5 million international units of IFN in one drop (0.05 mL ) in each nostril, twice a day, for 10 consecutive days. The nondetection of SARS-CoV-2 by real-time polymerase chain reaction was the primary outcome variable. Several IFN-α biomarkers, including intranasal gene expression and innate immune effector activity, were increased in participants who received intranasal IFN-α2b. The study included 2,930 international travelers and 5,728 persons who were their close contacts. The subjects were treated with Nasalferon in January 2021, and 9,162 untreated travelers were included as controls. COVID-19 rate in treated subjects was significantly lower than in untreated subjects (0.05% vs. 4.84%). The proportion of travelers with COVID-19 decreased from 60.9% to 2.2% between December 2020 and February 2021. Furthermore, 1,719 tourism workers also received Nasalferon, and no cases of SARS-CoV-2 infection were detected, whereas 39 COVID-19 cases (10.6%) were reported in 367 untreated subjects. The main adverse events associated with the use of intranasal IFN-α2b were nasal congestion, headache, and rhinorrhea. Our prophylactic health interventions study demonstrates that the daily administration of Nasalferon for 10 days decreases the risk of developing COVID-19 in healthy volunteers. [Figure: see text].

Expression and purification of human interferon alpha 2a (IFNα2a) in the methylotrophic yeast Pichia pastoris

Human interferon alpha 2a (IFNα2a) is a secreted glycoprotein that exerts a wide spectrum of biological effects, such as triggering of antiviral, antitumor and immunosuppressive responses. IFNα2a is used as pharmaceutical polypeptide in chronic hepatitis C virus (HCV) infection, chronic myelogenous leukemia, advanced renal cell carcinoma, and metastatic malignant melanoma. So far, the pharmaceutical polypeptide of this cytokine is produced in prokaryotic expression systems (E. coli). Here we report the expression and purification of recombinant human IFNα2a in the methylotrophic yeast Pichia pastoris. The cDNA encoding for human IFNα2a, modified to bear the P. pastoris codon bias, was cloned into the pPinkα-HC vector in order to be expressed as a secreted protein upon induction. Proper expression and secretion of recombinant human IFNα2a (approximately 19 kDa) was confirmed by PCR-sequencing, SDS-PAGE and Western blot analysis following methanol-induced expression in a number of individual transformed strains. Purification of the recombinant protein was performed by affinity chromatography, achieving a robust yield of purified active form. The purified recombinant protein showed an impressive stability to thermal denaturation as observed by Differential Scanning Fluorimetry. The biological activity of the P. pastoris-produced IFNα2a was confirmed in A549 and HT29 cells by monitoring transcriptional up-regulation of a panel of known interferon-stimulated genes (ISGs). Our results document that the P. pastoris expression system is a suitable system for producing biologically functional IFNα2a in a secreted form.

COVID-19 mRNA vaccine, but not a viral vector-based vaccine, promotes neutralizing anti-type I interferon autoantibody production in a small group of healthy individuals

Coronavirus disease 2019 (COVID-19) vaccines are highly effective but also induce adverse events, in particular, autoimmunity. Findings from several studies revealed that patients with life-threatening SARS-CoV-2 infection had increased, pre-existing, neutralizing antibodies against type I interferons (IFNs). However, whether COVID-19 vaccination induces the anti-type I IFN antibody remains unclear. In the current study, we evaluated plasma levels of 103 autoantibodies against various human self-antigens and 16 antibodies against viral antigens in healthy individuals pre- and post-COVID-19 vaccination. Twelve participants received a COVID-19 mRNA vaccine (Pfizer-BioNTech or Moderna), and 8 participants received a viral vector-based vaccine (Janssen). All participants produced increased antibody levels against SARS-CoV-2 antigens following vaccination. Among the 103 autoantibodies, only plasma levels of IgG autoantibodies against type I IFNs increased in participants who received a mRNA vaccine (3/12), but not in those who received the viral vector-based vaccine (0/8) at postvaccination compared to pre-vaccination. Among the three individuals showing increased anti-IFN IgG following vaccination, both plasma samples and plasma-purified total IgGs showed a dose-dependent binding ability to IFN-α; two of the three showed neutralizing activity to IFN-α-2a-induced phosphorated STAT1 responses in human peripheral blood mononuclear cells postvaccination compared to baseline in vitro. Among the 103 autoantibodies tested, the COVID-19 mRNA vaccine, but not the viral vector-based vaccine, specifically induced neutralizing anti-type I IFN autoantibodies in a small group of healthy individuals (~10%). Findings from this study imply that COVID-19 mRNA vaccines may suppress IFN-mediated innate immunity and impair immune defense through induced autoimmunity in some healthy individuals, who may need to switch to another type of COVID-19 vaccine (e.g., a viral vector-based vaccine).

Immunohematologic Biomarkers in COVID-19: Insights into Pathogenesis, Prognosis, and Prevention

Coronavirus disease 2019 (COVID-19) has had profound effects on the health of individuals and on healthcare systems worldwide. While healthcare workers on the frontlines have fought to quell multiple waves of infection, the efforts of the larger research community have changed the arch of this pandemic as well. This review will focus on biomarker discovery and other efforts to identify features that predict outcomes, and in so doing, identify possible effector and passenger mechanisms of adverse outcomes. Identifying measurable soluble factors, cell-types, and clinical parameters that predict a patient's disease course will have a legacy for the study of immunologic responses, especially stimuli, which induce an overactive, yet ineffectual immune system. As prognostic biomarkers were identified, some have served to represent pathways of therapeutic interest in clinical trials. The pandemic conditions have created urgency for accelerated target identification and validation. Collectively, these COVID-19 studies of biomarkers, disease outcomes, and therapeutic efficacy have revealed that immunologic systems and responses to stimuli are more heterogeneous than previously assumed. Understanding the genetic and acquired features that mediate divergent immunologic outcomes in response to this global exposure is ongoing and will ultimately improve our preparedness for future pandemics, as well as impact preventive approaches to other immunologic diseases.

Safety, Tolerability, Bioavailability, and Biological Activity of Inhaled Interferon-α2b in Healthy Adults: The IN2COVID Phase I Randomized Trial

BACKGROUND AND OBJECTIVES

Interferons have been identified as a potential treatment alternative for coronavirus disease 2019. This study assessed the safety, tolerability, bioavailability, and biological activity of inhaled interferon-α2b (IFN)-α2b in healthy adults.

METHODS

A double-blind, randomized, phase I clinical trial was conducted with two cohorts of healthy subjects aged 18-50 years. The first cohort received 2.5 MIU of inhaled IFN-α2b twice daily for 10 days (n = 6) or placebo (n = 3); the second cohort received 5.0 MIU of inhaled IFN-α2b in a similar scheme (n = 6) or placebo (n = 3). The first two doses were administered in an emergency department, then participants completed their treatment at home. Safety was measured through vital signs, new symptoms, and laboratory tests. Tolerability was measured as participants' treatment acceptability. Bioavailability and biological activity were measured from serum IFNα concentrations and real-time quantitative polymerase chain reaction of interferon-induced genes in blood before and after treatments.

RESULTS

Exposure to inhaled IFN-α2b at 2.5-MIU or 5-MIU doses did not produce statistically significant changes in participant vital signs, or elicit new symptoms, and standard hematological and biochemical blood measurements were comparable to those recorded in individuals who received placebo. A total of 58 adverse events were observed. All were mild or moderate and did not require medical care. All participants reported very high tolerability towards a twice-daily nebulized treatment for 10 days (98.0, 97.0, and 97.0 in the placebo, 2.5-MIU, and 5-MIU groups, respectively, on a 0- to 100-mm visual analog scale). A dose-dependent mild increase in serum IFN-α concentrations and an increase in serum RNA expression of IFN-induced genes were observed 11 days after treatment (p < 0.05 for all between-group comparisons).

CONCLUSIONS

Inhaled IFN-α2b was preliminarily safe and well tolerated, and induced systemic biological activity in healthy subjects.

CLINICAL TRIAL REGISTRATION

The trial was registered in ClinicalTrials.gov (NCT04988217), 3 August, 2021.

SARS-CoV-2 Evasion of the Interferon System: Can We Restore Its Effectiveness?

Type I and III Interferons (IFNs) are the first lines of defense in microbial infections. They critically block early animal virus infection, replication, spread, and tropism to promote the adaptive immune response. Type I IFNs induce a systemic response that impacts nearly every cell in the host, while type III IFNs' susceptibility is restricted to anatomic barriers and selected immune cells. Both IFN types are critical cytokines for the antiviral response against epithelium-tropic viruses being effectors of innate immunity and regulators of the development of the adaptive immune response. Indeed, the innate antiviral immune response is essential to limit virus replication at the early stages of infection, thus reducing viral spread and pathogenesis. However, many animal viruses have evolved strategies to evade the antiviral immune response. The Coronaviridae are viruses with the largest genome among the RNA viruses. Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2) caused the coronavirus disease 2019 (COVID-19) pandemic. The virus has evolved numerous strategies to contrast the IFN system immunity. We intend to describe the virus-mediated evasion of the IFN responses by going through the main phases: First, the molecular mechanisms involved; second, the role of the genetic background of IFN production during SARS-CoV-2 infection; and third, the potential novel approaches to contrast viral pathogenesis by restoring endogenous type I and III IFNs production and sensitivity at the sites of infection.

Therapeutic Effectiveness of Interferon-α2b against COVID-19 with Community-Acquired Pneumonia: The Ukrainian Experience

Despite several targeted antiviral drugs against SARS-CoV-2 currently being available, the application of type I interferons (IFNs) still deserves attention as an alternative antiviral strategy. This study aimed to assess the therapeutic effectiveness of IFN-α in hospitalized patients with COVID-19-associated pneumonia. The prospective cohort study included 130 adult patients with coronavirus disease (COVID-19). A dose of 80,000 IU of IFN-α2b was administered daily intranasally for 10 days. Adding IFN-α2b to standard therapy reduces the length of the hospital stay by 3 days (p < 0.001). The level of CT-diagnosed lung injuries was reduced from 35% to 15% (p = 0.011) and CT injuries decreased from 50% to 15% (p = 0.017) by discharge. In the group of patients receiving IFN-α2b, the SpO2 index before and after treatment increased from 94 (92-96, Q₁-Q₃) to 96 (96-98, Q₁-Q₃) (p < 0.001), while the percentage of patients with normal saturation increased (from 33.9% to 74.6%, p < 0.05), but the level of SpO2 decreased in the low (from 52.5% to 16.9%) and very low (from 13.6% to 8.5%) categories. The addition of IFN-α2b to standard therapy has a positive effect on the course of severe COVID-19.

Warmer ambient air temperatures reduce nasal turbinate and brain infection, but increase lung inflammation in the K18-hACE2 mouse model of COVID-19

Warmer climatic conditions have been associated with fewer COVID-19 cases. Herein we infected K18-hACE2 mice housed at the standard animal house temperature of ∼22 °C, or at ∼31 °C, which is considered to be thermoneutral for mice. On day 2 post infection, RNA-Seq analyses showed no significant differential gene expression lung in lungs of mice housed at the two temperatures, with almost identical viral loads and type I interferon responses. There was also no significant difference in viral loads in lungs on day 5, but RNA-Seq and histology analyses showed clearly elevated inflammatory signatures and infiltrates. Thermoneutrality thus promoted lung inflammation. On day 2 post infection mice housed at 31 °C showed reduced viral loads in nasal turbinates, consistent with increased mucociliary clearance at the warmer ambient temperature. These mice also had reduced virus levels in the brain, and an ensuing amelioration of weight loss and a delay in mortality. Warmer air temperatures may thus reduce infection of the upper respiratory track and the olfactory epithelium, resulting in reduced brain infection. Potential relevance for anosmia and neurological sequelae in COVID-19 patients is discussed.

Efficacy of interferon alpha for the treatment of hospitalized patients with COVID-19: A meta-analysis

INTRODUCTION

IFN-α intervention may block SARS-CoV-2 replication and normalize the deregulated innate immunity of COVID-19.

AIM

This meta-analysis aimed to investigate the efficacy of interferon IFN-α-containing regimens when treating patients with moderate-to-severe COVID-19.

MATERIAL AND METHODS

PubMed, SCOPUS, and ClinicalTrials.gov were searched from inception to 15 January 2022. A systematic literature search was conducted by applying relevant terms for 'COVID-19' and 'interferon-α'. The primary outcome enclosed the all-cause hospital mortality. The secondary outcomes constituted the length of hospital stay; hospital discharge; nucleic acid negative conversion.

RESULTS

Eleven studies are enclosed in the meta-analysis. No significant difference in the all-cause mortality rate was found between the study and control groups (OR 0.2; 95% CI 0.05-1.2; I2 = 96%). The implementation of interferon did not influence such outcomes as the length of hospital stay (OR 0.9; 95% CІ, 0.3-2.6; I2 = 91%), nucleic acid negative conversion (OR 0.8; 95% CI, 0.04-17.2; I2 = 94%). Nevertheless, IFN-α treatment resulted in a higher number of patients discharged from the hospital (OR 26.6; 95% CІ, 2.7-254.3; I2 = 95%).

CONCLUSIONS

Thus, IFN-α does not benefit the survival of hospitalized COVID-19 patients but may increase the number of patients discharged from the hospital.

SYSTEMATIC REVIEW REGISTRATION

www.crd.york.ac.uk/prospero, identifier (CRD42022374589).

Pharmacological therapies and drug development targeting SARS-CoV-2 infection

The development of therapies for SARS-CoV-2 infection, based on virus biology and pathology, and of large- and small-scale randomized controlled trials, have brought forward several antiviral and immunomodulatory drugs targeting the disease severity. Casirivimab/Imdevimab monoclonal antibodies and convalescent plasma to prevent virus entry, Remdesivir, Molnupiravir, and Paxlovid nucleotide analogs to prevent viral replication, a variety of repurposed JAK-STAT signaling pathway inhibitors, corticosteroids, and recombinant agonists/antagonists of cytokine and interferons have been found to provide clinical benefits in terms of mortality and hospitalization. However, current treatment options face multiple clinical needs, and therefore, in this review, we provide an update on the challenges of the existing therapeutics and highlight drug development strategies for COVID-19 therapy, based on ongoing clinical trials, meta-analyses, and clinical case reports.

Impact of COVID-19 on the liver and on the care of patients with chronic liver disease, hepatobiliary cancer, and liver transplantation: An updated EASL position paper

The COVID-19 pandemic has presented a serious challenge to the hepatology community, particularly healthcare professionals and patients. While the rapid development of safe and effective vaccines and treatments has improved the clinical landscape, the emergence of the omicron variant has presented new challenges. Thus, it is timely that the European Association for the Study of the Liver provides a summary of the latest data on the impact of COVID-19 on the liver and issues guidance on the care of patients with chronic liver disease, hepatobiliary cancer, and previous liver transplantation, as the world continues to deal with the consequences of the COVID-19 pandemic.

SARS-CoV-2 modulation of RIG-I-MAVS signaling: Potential mechanisms of impairment on host antiviral immunity and therapeutic approaches

The coronavirus disease 2019 (COVID-19) is a global infectious disease aroused by RNA virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Patients may suffer from severe respiratory failure or even die, posing a huge challenge to global public health. Retinoic acid-inducible gene I (RIG-I) is one of the major pattern recognition receptors, function to recognize RNA viruses and mediate the innate immune response. RIG-1 and melanoma differentiation-associated gene 5 contain an N-terminal caspase recruitment domain that is activated upon detection of viral RNA in the cytoplasm of virus-infected cells. Activated RIG-I and mitochondrial antiviral signaling (MAVS) protein trigger a series of corresponding immune responses such as the production of type I interferon against viral infection. In this review, we are summarizing the role of the structural, nonstructural, and accessory proteins from SARS-CoV-2 on the RIG-I-MAVS pathway, and exploring the potential mechanism how SARS-CoV-2 could evade the host antiviral response. We then proposed that modulation of the RIG-I-MAVS signaling pathway might be a novel and effective therapeutic strategy to against COVID-19 as well as the constantly mutating coronavirus.

SARS-CoV-2 and the Nucleus

The ongoing COVID-19 pandemic is caused by an RNA virus, SARS-CoV-2. The genome of SARS-CoV-2 lacks a nuclear phase in its life cycle and is replicated in the cytoplasm. However, interfering with nuclear trafficking using pharmacological inhibitors greatly reduces virus infection and virus replication of other coronaviruses is blocked in enucleated cells, suggesting a critical role of the nucleus in virus infection. Here, we summarize the alternations of nuclear pathways caused by SARS-CoV-2, including nuclear translocation pathways, innate immune responses, mRNA metabolism, epigenetic mechanisms, DNA damage response, cytoskeleton regulation, and nuclear rupture. We consider how these alternations contribute to virus replication and discuss therapeutic treatments that target these pathways, focusing on small molecule drugs that are being used in clinical studies.

Anti-IFN-α/-ω neutralizing antibodies from COVID-19 patients correlate with downregulation of IFN response and laboratory biomarkers of disease severity

A significant number of COVID‐19 patients were shown to have neutralizing antibodies (NAB) against IFN; however, NAB specificity, fluctuation over time, associations with biochemical and hematological parameters, and IFN gene expression are not well characterized.

Binding antibodies (BAB) to IFN‐α/‐β were screened in COVID‐19 patients’ serum. All BAB positive sera, and a subset of respiratory samples, were tested for NAB against IFN‐α/‐β/‐ω, using an antiviral bioassay. Transcript levels of IFN‐α/‐β/‐ω and IFN‐stimulated genes (ISGs) were quantified.

Anti‐IFN‐I BAB were found in 61 out of 360 (17%) of patients. Among BAB positive sera, 21.3% had a high NAB titer against IFN‐α. A total of 69.2% of anti‐IFN‐α NAB sera displayed cross‐reactivity to IFN‐ω. Anti‐IFN‐I NAB persisted in all patients. NAB to IFN‐α were also detected in 3 out of 17 (17.6%) of respiratory samples. Anti‐IFN‐I NAB were higher in males (p = 0.0017), patients admitted to the ICU (p < 0.0001), and patients with a fatal outcome (p < 0.0001). NAB were associated with higher levels of CRP, LDH, d‐Dimer, and higher counts of hematological parameters. ISG‐mRNAs were reduced in patients with persistently NAB titer.

NAB are detected in a significant proportion of severe COVID‐19. NAB positive patients presented a defective IFN response and increased levels of laboratory biomarkers of disease severity.