Potential Antiviral Drugs for SARS-Cov-2 Treatment: Preclinical Findings and Ongoing Clinical Research

Study of different heterocycles showing significant anti-severe acute respiratory syndrome 2 activity in vitro and in vivo

Background and Aim

With the emergence of severe acute respiratory syndrome-related coronavirus (SARS-CoV-2), antiviral drug development has gained increased significance due to the high incidence and potentially severe complications of the resulting coronavirus infection. Heterocycle compounds, acting as antimetabolites of DNA and RNA monomers, rank among the most effective antiviral drugs. These compounds' antiviral effects on various SARS-CoV-2 isolates, as found in existing data collections, form the basis for further research. The aim of this study was to examine the possible antiviral effect of some originally synthesized heterocyclic compounds.

Materials and Methods

The main methods were cell culturing, cytotoxicity assay, qRT-PCR assay, tissue and blood cells analysis, and micro-computed tomography (micro-CT) imaging.

Results

In both in vitro and in vivo conditions, the elimination of SARS-Cov-2 occurred significantly earlier after administration of the compounds compared to the control group. In hamsters, the primary symptoms of coronavirus disease disappeared following administration of heterocycle compounds.

Conclusion

Using delta and omicron strains of the SARS-CoV-2 virus, newly created heterocycle compound analogs dramatically reduced SARS-CoV-2 multiplication, resulting in a drop in viral RNA load in the supernatant under in vitro conditions. Improvements in pathological manifestations in the blood, bone marrow, and internal organs of hamsters demonstrated that heterocycle compounds inhibited SARS-CoV-2 replication both in vitro and in vivo.

SARS-CoV-2 Neutralization by Cell Membrane-Coated Antifouling Nanoparticles

The global outbreak of the COVID-19 pandemic has indisputably wreaked havoc on societies worldwide, compelling the scientific community to seek urgently needed therapeutic agents with low-cost and low-side effect profiles. Numerous approaches have been investigated in the quest to prevent or treat COVID-19, but many of them exhibit unwelcome side effects, such as dysfunctional viral immune responses and inflammation. Herein, we present the preparation of solid natural human pulmonary alveolar epithelial cell (ATII) membrane-coated PLGA NPs (PLGA NPs@ATII-M), which demonstrate remarkable affinity and competitiveness to neutralize the SARS-CoV-2 S1 protein-coated NPs (SCMMA NPs-S1), which are employed as a surrogate for coronavirus particles. In addition, we first considered the antifouling properties of these types of NPs, and we found that this membrane-coated NP formulation boasts excellent antifouling capabilities, which serve to protect their neutralization properties out of shielding by protein coronas in blood circulation. Moreover, this formulation is easily prepared and stored with a low-cost profile and exhibits good specificity, high targeting efficiency, and potentially side effect avoiding, thus making it a highly promising candidate for COVID-19 treatment.

Preclinical and Clinical Investigations of Potential Drugs and Vaccines for COVID-19 Therapy: A Comprehensive Review With Recent Update

The COVID-19 pandemic-led worldwide healthcare crisis necessitates prompt societal, ecological, and medical efforts to stop or reduce the rising number of fatalities. Numerous mRNA based vaccines and vaccines for viral vectors have been licensed for use in emergencies which showed 90% to 95% efficacy in preventing SARS-CoV-2 infection. However, safety issues, vaccine reluctance, and skepticism remain major concerns for making mass vaccination a successful approach to treat COVID-19. Hence, alternative therapeutics is needed for eradicating the global burden of COVID-19 from developed and low-resource countries. Repurposing current medications and drug candidates could be a more viable option for treating SARS-CoV-2 as these therapies have previously passed a number of significant checkpoints for drug development and patient care. Besides vaccines, this review focused on the potential usage of alternative therapeutic agents including antiviral, antiparasitic, and antibacterial drugs, protease inhibitors, neuraminidase inhibitors, and monoclonal antibodies that are currently undergoing preclinical and clinical investigations to assess their effectiveness and safety in the treatment of COVID-19. Among the repurposed drugs, remdesivir is considered as the most promising agent, while favipiravir, molnupiravir, paxlovid, and lopinavir/ritonavir exhibited improved therapeutic effects in terms of elimination of viruses. However, the outcomes of treatment with oseltamivir, umifenovir, disulfiram, teicoplanin, and ivermectin were not significant. It is noteworthy that combining multiple drugs as therapy showcases impressive effectiveness in managing individuals with COVID-19. Tocilizumab is presently employed for the treatment of patients who exhibit COVID-19-related pneumonia. Numerous antiviral drugs such as galidesivir, griffithsin, and thapsigargin are under clinical trials which could be promising for treating COVID-19 individuals with severe symptoms. Supportive treatment for patients of COVID-19 may involve the use of corticosteroids, convalescent plasma, stem cells, pooled antibodies, vitamins, and natural substances. This study provides an updated progress in SARS-CoV-2 medications and a crucial guide for inventing novel interventions against COVID-19.

Identification of Cyanobacteria-Based Natural Inhibitors Against SARS-CoV-2 Druggable Target ACE2 Using Molecular Docking Study, ADME and Toxicity Analysis

In 2019-2020, the novel "severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)" had emerged as the biggest challenge for humanity, causing "coronavirus disease 19 (COVID-19)". Scientists around the world have been putting continuous efforts to unfold potential inhibitors of SARS-CoV-2. We have performed computational studies that help us to identify cyanobacterial photoprotective compounds as potential inhibitors against SARS-CoV-2 druggable target human angiotensin-converting enzyme (ACE2), which plays a vital role in the attachment and entry of the virus into the cell. Blocking the receptor-binding domain of ACE2 can prevent the access of the virus into the compartment. A molecular docking study was performed between photoprotective compounds mycosporine-like amino acids, scytonemins and ACE2 protein using AutoDock tools. Among sixteen molecularly docked metabolites, seven compounds were selected with binding energy < 6.8 kcal/mol. Afterwards, drug-likeness and toxicity of the top candidate were predicted using Swiss ADME and Pro Tox-II online servers. All top hits show desirable drug-likeness properties, but toxicity pattern analysis discloses the toxic effect of scytonemin and its derivatives, resulting in the elimination from the screening pipeline. Further molecular interaction study of the rest two ligands, mycosporine-glycine-valine and shinorine with ACE2 was performed using PyMol, Biovia Discovery studio and LigPlot+. Lastly biological activity of both the ligands was predicted by using the PASS online server. Combining the docking score and other studied properties, we believe that mycosporine-glycine-valine and shinorine have potential to be potent inhibitors of ACE2 and can be explored further to use against COVID-19.

[Antiviral activity of basidial fungus Inonotus obliquus aqueous extract against SARS-CоV-2 virus (Coronaviridae: Betacoronavirus: Sarbecovirus) in vivo in BALB/c mice model]

INTRODUCTION

The COVID-19 pandemic combined with seasonal epidemics of respiratory viral diseases requires targeted antiviral prophylaxis with restorative and immunostimulant drugs. The compounds of natural origin are low-toxic, but active against several viruses at the same time. One of the most famous compounds is Inonotus obliquus aqueous extract. The fruit body of basidial fungus I. obliquus is called Chaga mushroom. The aim of the work ‒ was to study the antiviral activity of I. obliquus aqueous extract against the SARS-CoV-2 virus in vivo.

MATERIALS AND METHODS

Antiviral activity of I. obliquus aqueous extract sample (#20-17) was analyzed against strain of SARS-CoV-2 Omicron ВА.5.2 virus. The experiments were carried out in BALB/c inbred mice. The SARS-CoV-2 viral load was measured using quantitative real-time PCR combined with reverse transcription. The severity of lung tissue damage was assessed by histological methods.

RESULTS

The peak values of the viral load in murine lung tissues were determined 72 hours after intranasal inoculation at dose of 2,85 lg TCID50. The quantitative real-time PCR testing has shown a significant decrease in the viral load compared to the control group by 4,65 lg copies/ml and 5,72 lg copies/ml in the lung tissue and nasal cavity samples, respectively. Histological methods revealed that the decrease in the number and frequency of observed pathomorphological changes in murine lung tissues depended on the introduction of the compound under study.

CONCLUSION

The results obtained indicate the possibility of using basidial fungus Inonotus obliquus aqueous extract as a preventive agent against circulating variants of SARS-CoV-2 virus.

Remdesivir analogs against SARS-CoV-2 RNA-dependent RNA polymerase

The COVID-19 pandemic has already taken many lives but is still continuing its spread and exerting jeopardizing effects. This study is aimed to find the most potent ligands from 703 analogs of remdesivir against RNA-dependent RNA polymerase (RdRp) protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) virus . RdRp is a major part of a multi-subunit transcription complex of the virus, which is essential for viral replication. In clinical trials, it has been found that remdesivir is effective to inhibit viral replication in Ebola and in primary human lung cell cultures; it effectively impedes replication of a broad-spectrum pre-pandemic bat coronaviruses and epidemic human coronaviruses. After virtual screening, 30 most potent ligands and remdesivir were modified with triphosphate. Quantum mechanics-based quantitative structure-activity relationship envisages the binding energy for ligands applying partial least square (PLS) regression. PLS regression remarkably predicts the binding energy of the effective ligands with an accuracy of 80% compared to the value attained from molecular docking. Two ligands (L4:58059550 and L28:126719083), which have more interactions with the target protein than the other ligands including standard remdesivir triphosphate, were selected for further analysis. Molecular dynamics simulation is done to assess the stability and dynamic nature of the drug-protein complex. Binding-free energy results via PRODIGY server and molecular mechanics/Poisson-Boltzmann surface area method depict that the potential and solvation energies play a crucial role. Considering all computational analysis, we recommend the best remdesivir analogs can be utilized for efficacy test through in vitro and in vivo trials against SARS-CoV-2.Communicated by Ramaswamy H. Sarma.

Screening and evaluation of cytotoxicity and antiviral effects of secondary metabolites from water extracts of Bersama abyssinica against SARS-CoV-2 Delta

Background

Bersama abyssinica is a common herb in Africa, with diverse medical uses in different areas. The plant is well-known in Tanzania for treating respiratory disorders such as TB, tonsillitis, bronchitis, and asthma, and it has lately been utilized to treat COVID-19 symptoms. Water extract of leaf and stem bark has been registered as an herbal medication known as 'Coviba Dawa' in Tanzania for the relief of bacterial respiratory infections. The extracts, however, have not been scientifically tested for their anti-viral activities. The aim of this work was to test for the cytotoxicity and antiviral effects of bioactive ingredients from B. abyssinica extracts against the Delta variant of the SARS-CoV-2 coronavirus.

Methods

B. abyssinica leaves and stem bark were dried under shade in room temperature and then pulverized to obtain small pieces before soaking into different solvents. One hundred grams of each, leaves and stem bark, were extracted in petroleum ether, dichloromethane, ethyl acetate and methanol. Water extract was obtained by decoction of stem bark and leaves into water. Phenols, flavonoids, tannins, and antioxidants were confirmed as components of the extracts. Analysis of polar extracts of bark stem bark and leaves was done. Antiviral screening and cytotoxicity experiments were conducted in a Biosafety Level 3 (BSL-3) Laboratory facility according to International Standard Operating Procedures (SOPs).

Results

By the use of LC–MS/MS analysis, this study confirmed the existence of four phenolic compounds in B. abyssinica water extract; 2,4-di-tert-butylphenol, 4-formyl-2-methoxyphenyl propionate, 7,8-Dihydroxy-4-methylcoumarin, and 2,3, 6-trimethoxyflavone with antioxidant activity. This study showed that, while the water extracts of B. abyssinica had significant antiviral activity against SARS Cov2 virus, it showed no cytotoxicity effect on Vero E6 cells. In particular, the water extract (Coviba dawa) showed 75% while ethylacetate fraction of B. abyssinica leaves showed a 50% in vitro viral inhibition, indicating that these substances may be useful for the development of future anti-viral agents.

Conclusion

We therefore recommend isolation of compounds for further profiling and development with a broader concentration range. We further recommend studies that determine the antiviral activity of extracts of B.abyssinica on other viral pathogens of clinical concern.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12906-022-03754-3.

Clinical Protocol for Early Treatment of COVID-19 in a real-world scenario: results of a series of patients

Introduction

Despite the advance in vaccination, the SARS-CoV-2 infection remains a challenge for the medical community. Outpatient and hospital therapy for COVID-19 are still improving. Our study aimed to report the results of a series of patients with COVID-19 who participated in an outpatient treatment protocol since the first clinical manifestation.

Methods

A case series report of individuals aged ≥ 18 years with clinical symptoms and a confirmed test for COVID-19 submitted to a treatment protocol. Patients were enrolled between May and September 2020 and followed for at least 15 days. The assessed clinical outcomes were the need for hospitalization, admission to the intensive care unit, orotracheal intubation, and death.

Results

We studied a 116 patients. The mean age was 48 ± 14 years. Females formed 53%. The main comorbidities wereobesity (15.5%), systemic arterial hypertension (10.3%) ,type II diabetes (6%), and lung diseases (6.0%). Temperature > 37.7 °C (51.7%), cough (55.2%), myalgia (37.1%), headache (37.9%), and fatigue (34.5%) were the most frequent signs and symptoms. According to different disease staging, the most administered drugs were: azithromycin, ivermectin, corticosteroid, antibiotics, and anticoagulants. There was no death, and hospitalization accounted for only 8.6% of the patients (1 in ICU); none required orotracheal intubation. The mean length of hospital stay was 5.8 days.

Adverse Effects of Anti-Covid-19 Drug Candidates and Alcohol on Cellular Stress Responses of Hepatocytes

During the pandemic, dexamethasone (DEX), remdesivir (RDV), hydroxychloroquine (HCQ), thapsigargin (TG), camostat mesylate (CaM), and pralatrexate were repurposed drugs for coronavirus disease 2019 (COVID-19). However, the side effects on the liver associated with the anti-COVID therapies are unknown. Cellular stresses by these drugs at 0-30 μM were studied using HepG2, Huh7, and/or primary human hepatocytes. DEX or RDV induced endoplasmic reticulum stress with increased X-box binding protein 1 and autophagic response with increased accumulation of microtubule-associated protein 1A/1B-light chain 3 (LC3-II). DEX and RDV had additive effects on the stress responses in the liver cells, which further increased expression of activating transcription factor 4 and C/EBP homology protein 1 (CHOP), and cell death. Alcohol pretreatment (50 mM) and DEX induced greater cellular stress responses than DEX and RDV. Pralatrexate induced Golgi fragmentation, cell cycle arrest at G0/G1 phase, activations of poly (ADP-ribose) polymerase-1 (PARP) and caspases, and cell death. Pralatrexate and alcohol had synergistic effects on the cell death mediators of Bim, caspase3, and PARP. The protease inhibitor CaM and TG induced autophagic response and mitochondrial stress with altered mitochondrial membrane potential, B-cell lymphoma 2, and cytochrome C. TG and HCQ induced autophagic response markers of Unc-51 like autophagy activating kinase, LC3-II, Beclin1, and Atg5, and severe ER stress marker CHOP. Conclusion: These results suggest that the anti-COVID-19 drugs, especially with drug-drug or alcohol-drug combinations, cause cellular stress responses and injuries in the liver cells.

Major Update 2: Remdesivir for Adults With COVID-19: A Living Systematic Review and Meta-analysis for the American College of Physicians Practice Points

BACKGROUND

Remdesivir is approved for the treatment of adults hospitalized with COVID-19.

PURPOSE

To update a living review of remdesivir for adults with COVID-19.

DATA SOURCES

Several electronic U.S. Food and Drug Administration, company, and journal websites from 1 January 2020 through 19 October 2021.

STUDY SELECTION

English-language, randomized controlled trials (RCTs) of remdesivir for COVID-19.

DATA EXTRACTION

One reviewer abstracted, and a second reviewer verified data. The Cochrane Risk of Bias Tool and GRADE (Grading of Recommendations Assessment, Development and Evaluation) method were used.

DATA SYNTHESIS

Since the last update (search date 9 August 2021), 1 new RCT and 1 new subtrial comparing a 10-day course of remdesivir with control (placebo or standard care) were identified. This review summarizes and updates the evidence on the cumulative 5 RCTs and 2 subtrials for this comparison. Our updated results confirm a 10-day course of remdesivir, compared with control, probably results in little to no mortality reduction (5 RCTs). Updated results also confirm that remdesivir probably results in a moderate increase in the proportion of patients recovered by day 29 (4 RCTs) and may reduce time to clinical improvement (2 RCTs) and hospital length of stay (4 RCTs). New RCTs, by increasing the strength of evidence, lead to an updated conclusion that remdesivir probably results in a small reduction in the proportion of patients receiving ventilation or extracorporeal membrane oxygenation at specific follow-up times (4 RCTs). New RCTs also alter the conclusions for harms-remdesivir, compared with control, may lead to a small reduction in serious adverse events but may lead to a small increase in any adverse event.

LIMITATION

The RCTs differed in definitions of COVID-19 severity and outcomes reported.

CONCLUSION

In hospitalized adults with COVID-19, the findings confirm that remdesivir probably results in little to no difference in mortality and increases the proportion of patients recovered. Remdesivir may reduce time to clinical improvement and may lead to small reductions in serious adverse events but may result in a small increase in any adverse event.

PRIMARY FUNDING SOURCE

U.S. Department of Veterans Affairs.

Development of superior antibodies against the S-protein of SARS-Cov-2 using macrocyclic epitopes

One of the proven methods to prevent and inhibit viral infections is to use antibodies to block the initial Receptor Binding Domain (RBD) of SARS-CoV-2 S protein and avoid its binding with the host cells. Thus, developing these RBD-targeting antibodies would be a promising approach for treating the SARS-CoV-2 infectious disease and stop virus replication. Macrocyclic epitopes constitute closer mimics of the receptor's actual topology and, as such, are expected to be superior epitopes for antibody generation. This work demonstrated the vital effect of the three-dimensional shape of epitopes on the developed antibodies' activity against RBD protein of SARS-CoV-2. The molecular dynamics studies showed the greater stability of the cyclic epitopes in comparison with the linear counterpart, which was reflected in the activity of their produced antibodies. Indeed, the antibodies we developed using macrocyclic epitopes showed superiority with respect to binding to RBD proteins compared to antibodies formed from a linear peptide. The results of the present work constitute a roadmap for developing superior antibodies that could be used to inhibit the activity of the SARS-CoV-2 and prevent its reproduction.

The quest for a better fight: How can nanomaterials address the current therapeutic and diagnostic obstacles in the fight against COVID-19?

The inexorable coronavirus disease 2019 (COVID-19) pandemic with around 226 million people diagnosed and approximately 4.6 million deaths, is still moving toward more frightening statistics, calling for the urgent need to explore solutions for the current challenges in therapeutic and diagnostic approaches. The challenges associated with existing therapeutics in COVID-19 include lack of in vivo stability, efficacy, and safety. Nanoparticles (NPs) can offer a handful of tools to tackle these problems by enabling efficacious and safe delivery of both virus- and host-directed therapeutics. Furthermore, they can enable maximized clinical outcome while eliminating the chance of resistance to therapy by tissue-targeting and concomitant delivery of multiple therapeutics. The promising application of NPs as vaccine platforms is reflected by the major advances in developing novel COVID-19 vaccines. Two of the most critical COVID-19 vaccines are mRNA-based vaccines delivered via NPs, making them the first FDA-approved mRNA vaccines. Besides, NPs have been deployed as simple, rapid, and precise tools for point of care disease diagnosis. Not enough said NPs can also be exploited in novel ways to expedite the drug discovery process. In light of the above, this review discusses how NPs can overcome the hurdles associated with therapeutic and diagnostic approaches against COVID-19.

Dysregulation of RNA interference components in COVID-19 patients

OBJECTIVE

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the novel coronavirus causing severe respiratory illness (COVID-19). This virus was initially identified in Wuhan city, a populated area of the Hubei province in China, and still remains one of the major global health challenges. RNA interference (RNAi) is a mechanism of post-transcriptional gene silencing that plays a crucial role in innate viral defense mechanisms by inhibiting the virus replication as well as expression of various viral proteins. Dicer, Drosha, Ago2, and DGCR8 are essential components of the RNAi system, which is supposed to be dysregulated in COVID-19 patients. This study aimed to assess the expression level of the mentioned mRNAs in COVID-19patients compared to healthy individuals.

RESULTS

Our findings demonstrated that the expression of Dicer, Drosha, and Ago2 was statistically altered in COVID-19 patients compared to healthy subjects. Ultimately, the RNA interference mechanism as a crucial antiviral defense system was suggested to be dysregulated in COVID-19 patients.

An Overview on the Potential Roles of EGCG in the Treatment of COVID-19 Infection

Coronavirus disease-19 (COVID-19) pandemic is currently ongoing worldwide and causes a lot of deaths in many countries. Although different vaccines for the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection have been developed and are now available, there are no effective antiviral drugs to treat the disease, except for Remdesivir authorized by the US FDA to counteract the emergency. Thus, it can be useful to find alternative therapies based on the employment of natural compounds, with antiviral features, to circumvent SARS-CoV-2 infection. Pre-clinical studies highlighted the antiviral activities of epigallocatechin-3-gallate (EGCG), a catechin primarily found in green tea, against various viruses, including SARS-CoV-2. In this review, we summarize this experimental evidence and highlight the potential use of EGCG as an alternative therapeutic choice for the treatment of SARS-CoV-2 infection.

Whey-Derived Peptides at the Heart of the COVID-19 Pandemic

The renin-angiotensin system (RAS) is a key regulator of blood pressure and hypertension. Angiotensin-converting enzyme 2 (ACE2) and angiotensin-converting enzyme I (ACE) are two main components of the RAS that play a major role in blood pressure homeostasis. The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) uses ACE2 as a receptor to enter cells. Despite some controversies, numerous studies have reported a significant association between the use of ACE inhibitors and reduced risk of COVID-19. In our previous studies, we produced and identified peptide sequences present in whey hydrolysates exhibiting high ACE inhibitory activity. Therefore, the aim of this work is to obtain an improved understanding of the function of these natural peptides as RAS inhibitors and investigate their potential therapeutic role in the COVID-19 pandemic. The molecular interactions between peptides IPP, LIVTQ, IIAE, LVYPFP, and human ACE2 were assessed by employing a molecular docking approach. The results show that natural whey-derived peptides have a dual inhibitory action against both ACE and ACE2. This dual activity distinguishes these ACE inhibitory peptides from synthetic drugs, such as Captopril and Lisinopril which were not shown to inhibit ACE2 activity, and may represent a potential strategy in the treatment of COVID-19.

Potential of Marine Terpenoids against SARS-CoV-2: An In Silico Drug Development Approach

In an emergency, drug repurposing is the best alternative option against newly emerged severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. However, several bioactive natural products have shown potential against SARS-CoV-2 in recent studies. The present study selected sixty-eight broad-spectrum antiviral marine terpenoids and performed molecular docking against two novel SARS-CoV-2 enzymes (main protease or Mpro or 3CLpro) and RNA-dependent RNA polymerase (RdRp). In addition, the present study analysed the physiochemical-toxicity-pharmacokinetic profile, structural activity relationship, and phylogenetic tree with various computational tools to select the 'lead' candidate. The genomic diversity study with multiple sequence analyses and phylogenetic tree confirmed that the newly emerged SARS-CoV-2 strain was up to 96% structurally similar to existing CoV-strains. Furthermore, the anti-SARS-CoV-2 potency based on a protein-ligand docking score (kcal/mol) exposed that the marine terpenoid brevione F (-8.4) and stachyflin (-8.4) exhibited similar activity with the reference antiviral drugs lopinavir (-8.4) and darunavir (-7.5) against the target SARS-CoV-Mpro. Similarly, marine terpenoids such as xiamycin (-9.3), thyrsiferol (-9.2), liouvilloside B (-8.9), liouvilloside A (-8.8), and stachyflin (-8.7) exhibited comparatively higher docking scores than the referral drug remdesivir (-7.4), and favipiravir (-5.7) against the target SARS-CoV-2-RdRp. The above in silico investigations concluded that stachyflin is the most 'lead' candidate with the most potential against SARS-CoV-2. Previously, stachyflin also exhibited potential activity against HSV-1 and CoV-A59 within IC50, 0.16-0.82 µM. Therefore, some additional pharmacological studies are needed to develop 'stachyflin' as a drug against SARS-CoV-2.

Evaluation of the Effects of Remdesivir and Hydroxychloroquine on Viral Clearance in COVID-19 : A Randomized Trial

BACKGROUND

New treatment modalities are urgently needed for patients with COVID-19. The World Health Organization (WHO) Solidarity trial showed no effect of remdesivir or hydroxychloroquine (HCQ) on mortality, but the antiviral effects of these drugs are not known.

OBJECTIVE

To evaluate the effects of remdesivir and HCQ on all-cause, in-hospital mortality; the degree of respiratory failure and inflammation; and viral clearance in the oropharynx.

DESIGN

NOR-Solidarity is an independent, add-on, randomized controlled trial to the WHO Solidarity trial that included biobanking and 3 months of clinical follow-up (ClinicalTrials.gov: NCT04321616).

SETTING

23 hospitals in Norway.

PATIENTS

Eligible patients were adults hospitalized with confirmed SARS-CoV-2 infection.

INTERVENTION

Between 28 March and 4 October 2020, a total of 185 patients were randomly assigned and 181 were included in the full analysis set. Patients received remdesivir (n = 42), HCQ (n = 52), or standard of care (SoC) (n = 87).

MEASUREMENTS

In addition to the primary end point of WHO Solidarity, study-specific outcomes were viral clearance in oropharyngeal specimens, the degree of respiratory failure, and inflammatory variables.

RESULTS

No significant differences were seen between treatment groups in mortality during hospitalization. There was a marked decrease in SARS-CoV-2 load in the oropharynx during the first week overall, with similar decreases and 10-day viral loads among the remdesivir, HCQ, and SoC groups. Remdesivir and HCQ did not affect the degree of respiratory failure or inflammatory variables in plasma or serum. The lack of antiviral effect was not associated with symptom duration, level of viral load, degree of inflammation, or presence of antibodies against SARS-CoV-2 at hospital admittance.

LIMITATION

The trial had no placebo group.

CONCLUSION

Neither remdesivir nor HCQ affected viral clearance in hospitalized patients with COVID-19.

PRIMARY FUNDING SOURCE

National Clinical Therapy Research in the Specialist Health Services, Norway.

Epidemiology, pathogenesis, clinical presentations, diagnosis and treatment of COVID-19: a review of current evidence

INTRODUCTION

The COVID-19 pandemic has created a public health crisis, infected millions of people, and caused a significant number of deaths. SARS-CoV-2 transmits from person to person through several routes, mainly via respiratory droplets, which makes it difficult to contain its spread into the community. Here, we provide an overview of the epidemiology, pathogenesis, clinical presentation, diagnosis, and treatment of COVID-19.

AREAS COVERED

Direct person-to-person respiratory transmission has rapidly amplified the spread of coronavirus. In the absence of any clinically proven treatment options, the current clinical management of COVID-19 includes symptom management, infection prevention and control measures, optimized supportive care, and intensive care support in severe or critical illness. Developing an effective vaccine is now a leading research priority. Some vaccines have already been approved by the regulatory authorities for the prevention of COVID-19.

EXPERT OPINION

General prevention and protection measures regarding the containment and management of the second or third waves are necessary to minimize the risk of infection. Until now, four vaccines reported variable efficacies of between 62-95%, and two of them (Pfizer/BioNTech and Moderna) received FDA emergency use authorization. Equitable access and effective distribution of these vaccines in all countries will save millions of lives.

GS-441524 inhibits African swine fever virus infection in vitro

African swine fever virus (ASFV) is a highly infectious and lethal swine pathogen that causes serious socio-economic consequences in endemic countries for which no safe and effective vaccine is currently available. GS-441524, a 1-cyano-substituted adenine C-nucleoside ribose analogue, inhibits viral RNA transcription by competing with natural nucleosides (ATP, TTP, CTP, and GTP) and effectively inhibits viral RNA-dependent RNA polymerase activity. However, whether GS-441524 can inhibit the replication of DNA viruses is unknown. In this study, we confirmed that GS-441524 inhibits ASFV infection in porcine alveolar macrophages (PAMs) in a dose-dependent manner; GS-441524 significantly inhibited ASFV replication at different time points after ASFV infection, particularly at the early stages of viral replication. Notably, GS-441524 did not increase the levels of antiviral cytokines or ATP in PAMs. However, an increase in the concentration of natural ATP in PAMs promoted the replication of ASFV and attenuated the inhibitory effect of GS-441524 in a dose-dependent manner. Our results suggest that GS-441524 is an effective antiviral against ASFV.

Resources and computational strategies to advance small molecule SARS-CoV-2 discovery: Lessons from the pandemic and preparing for future health crises

There is an urgent need to identify new therapies that prevent SARS-CoV-2 infection and improve the outcome of COVID-19 patients. This pandemic has thus spurred intensive research in most scientific areas and in a short period of time, several vaccines have been developed. But, while the race to find vaccines for COVID-19 has dominated the headlines, other types of therapeutic agents are being developed. In this mini-review, we report several databases and online tools that could assist the discovery of anti-SARS-CoV-2 small chemical compounds and peptides. We then give examples of studies that combined in silico and in vitro screening, either for drug repositioning purposes or to search for novel bioactive compounds. Finally, we question the overall lack of discussion and plan observed in academic research in many countries during this crisis and suggest that there is room for improvement.

Structure-based inhibitor screening of natural products against NSP15 of SARS-CoV-2 revealed thymopentin and oleuropein as potent inhibitors

Coronaviruses are enveloped, non-segmented positive-sense RNA viruses with the largest genome among RNA viruses. Their genome contains a large replicase ORF which encodes nonstructural proteins (NSPs), structural, and accessory genes. NSP15 is a nidoviral RNA uridylate-specific endoribonuclease (NendoU) with C-terminal catalytic domain. The endoribonuclease activity of NSP15 interferes with the innate immune response of the host. Here, we screened Selleckchem Natural product database of the compounds against NSP15, and we found that thymopentin and oleuropein displayed highest binding energies. The binding of these molecules was further validated by molecular dynamic simulations that revealed them as very stable complexes. These drugs might serve as effective counter molecules in the reduction of virulence of this virus; may be more effective if treated in combination with replicase inhibitors. Future validation of both these inhibitors is worth the consideration for patients being treated for COVID-19.

Emerging paradigms of viral diseases and paramount role of natural resources as antiviral agents

In the current scenario, the increasing prevalence of diverse microbial infections as well as emergence and re-emergence of viral epidemics with high morbidity and mortality rates are major public health threat. Despite the persistent production of antiviral drugs and vaccines in the global market, viruses still remain as one of the leading causes of deadly human diseases. Effective control of viral diseases, particularly Zika virus disease, Nipah virus disease, Severe acute respiratory syndrome, Coronavirus disease, Herpes simplex virus infection, Acquired immunodeficiency syndrome, and Ebola virus disease remain promising goal amidst the mutating viral strains. Current trends in the development of antiviral drugs focus solely on testing novel drugs or repurposing drugs against potential targets of the viruses. Compared to synthetic drugs, medicines from natural resources offer less side-effect to humans and are often cost-effective in the productivity approaches. This review intends not only to emphasize on the major viral disease outbreaks in the past few decades and but also explores the potentialities of natural substances as antiviral traits to combat viral pathogens. Here, we spotlighted a comprehensive overview of antiviral components present in varied natural sources, including plants, fungi, and microorganisms in order to identify potent antiviral agents for developing alternative therapy in future.

Clinical and Laboratory Profile of Hospitalized Symptomatic COVID-19 Patients: Case Series Study From the First COVID-19 Center in the UAE

INTRODUCTION

COVID-19 is raising with a second wave threatening many countries. Therefore, it is important to understand COVID-19 characteristics across different countries.

METHODS

This is a cross-sectional descriptive study of 525 hospitalized symptomatic COVID-19 patients, from the central federal hospital in Dubai-UAE during period of March to August 2020.

RESULTS

UAE's COVID-19 patients were relatively young; mean (SD) of the age 49(15) years, 130 (25%) were older than 60 and 4 (<1%) were younger than 18 years old. Majority were male(47; 78%). The mean (SD) BMI was 29 (6) kg/m2. While the source of contracting COVID-19 was not known in 369 (70%) of patients, 29 (6%) reported travel to overseas-country and 127 (24%) reported contact with another COVID-19 case/s. At least one comorbidity was present in 284 (54%) of patients and 241 (46%) had none. The most common comorbidities were diabetes (177; 34%) and hypertension (166; 32%). The mean (SD) of symptoms duration was 6 (3) days. The most common symptoms at hospitalization were fever (340; 65%), cough (296; 56%), and shortness of breath (SOB) (243; 46%). Most of the laboratory values were within normal range, but (184; 35%) of patients had lymphopenia, 43 (8%) had neutrophilia, and 116 (22%) had prolong international normalized ratio (INR), and 317 (60%) had high D-dimer. Chest x ray findings of consolidation was present in 334 (64%) of patients and CT scan ground glass appearance was present in 354 (68%). Acute cardiac injury occurred in 124 (24%), acute kidney injury in 111 (21%), liver injury in 101 (19%), ARDS in 155 (30%), acidosis in 118 (22%), and septic shock in 93 (18%). Consequently, 150 (29%) required ICU admission with 103 (20%) needed mechanical ventilation.

CONCLUSIONS

The study demonstrated the special profile of COVID-19 in UAE. Patients were young with diabetes and/or hypertension and associated with severe infection as shown by various clinical and laboratory data necessitating ICU admission.

Potential Efficacy of Nutrient Supplements for Treatment or Prevention of COVID-19

COVID-19 (COronaVIrus Disease of 2019), the disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), represents an ongoing global health challenge and the deadliest epidemic coronavirus outbreak to date. Early sequencing of the viral genome and knowledge from past coronavirus outbreaks (SARS-CoV-1 and Middle East Respiratory Syndrome, MERS) has led to rapid advances in knowledge of how the virus spreads and infects human hosts. Unfortunately, advancing knowledge has not yet produced a treatment that substantially lowers morbidity or mortality and only recently resulted in the development of a vaccine that prevents severe disease. Mounting evidence supports the notion that dietary supplementation of key essential nutrients may contribute to the body's defenses against infection as well as bolster the body's responses to infection. Evidence supporting the potential beneficial roles of vitamin C, vitamin D, zinc, and B3 vitamins is reviewed here, revealing a combination of basic research elucidating underlying mechanisms of action, preclinical studies and human intervention studies has led to the proliferation of registered clinical trials on COVID-19. Overall, the data suggest this collection of nutrients has a promising impact on reducing the risk and/or severity of COVID-19, although firm conclusions await the results of these trials.

Immune-checkpoint inhibitors from cancer to COVID‑19: A promising avenue for the treatment of patients with COVID‑19 (Review)

The severe acute respiratory syndrome associated coronavirus‑2 (SARS‑CoV‑2) poses a threat to human life worldwide. Since early March, 2020, coronavirus disease 2019 (COVID‑19), characterized by an acute and often severe form of pneumonia, has been declared a pandemic. This has led to a boom in biomedical research studies at all stages of the pipeline, from the in vitro to the clinical phase. In line with this global effort, known drugs, currently used for the treatment of other pathologies, including antivirals, immunomodulating compounds and antibodies, are currently used off‑label for the treatment of COVID‑19, in association with the supportive standard care. Yet, no effective treatments have been identified. A new hope stems from medical oncology and relies on the use of immune‑checkpoint inhibitors (ICIs). In particular, amongst the ICIs, antibodies able to block the programmed death‑1 (PD‑1)/PD ligand-1 (PD‑L1) pathway have revealed a hidden potential. In fact, patients with severe and critical COVID‑19, even prior to the appearance of acute respiratory distress syndrome, exhibit lymphocytopenia and suffer from T‑cell exhaustion, which may lead to viral sepsis and an increased mortality rate. It has been observed that cancer patients, who usually are immunocompromised, may restore their anti‑tumoral immune response when treated with ICIs. Moreover, viral-infected mice and humans, exhibit a T‑cell exhaustion, which is also observed following SARS‑CoV‑2 infection. Importantly, when treated with anti‑PD‑1 and anti‑PD‑L1 antibodies, they restore their T‑cell competence and efficiently counteract the viral infection. Based on these observations, four clinical trials are currently open, to examine the efficacy of anti‑PD‑1 antibody administration to both cancer and non‑cancer individuals affected by COVID‑19. The results may prove the hypothesis that restoring exhausted T‑cells may be a winning strategy to beat SARS‑CoV‑2 infection.

COVID-19: An overview and a clinical update

The outbreak of coronavirus disease-2019 (COVID-19, previously known as 2019 nCoV) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection in Wuhan City, China, has spread rapidly around the world. Most patients from the first cluster had an epidemiological connection to the Wuhan's Huanan Seafood Wholesale Market. Available evidence has shown that SARS-CoV-2 can be easily transmitted from person to person through close contact and respiratory droplets, posing a substantial challenge to public health. At present, the research on SARS-CoV-2 is still in the primary stages. However, dexa-methasone and remdesivir are appeared to be promising medical therapies. Still, there is no definite specific treatment, and the mainstay of treatment is still focused on supportive therapies. Currently, over 150 vaccines are under investigation. It is necessary to understand the nature of the virus and its clinical characteristics in order to find effectively manage the disease. The knowledge about this virus is rapidly evolving, and clinicians must update themselves regularly. The present review comprehensively summarizes the epidemiology, pathogenesis, clinical characteristics, and management of COVID-19 based on the current evidence.

Identification of novel inhibitors of angiotensin-converting enzyme 2 (ACE-2) receptor from Urtica dioica to combat coronavirus disease 2019 (COVID-19)

Abstract

The pandemic outbreak of coronavirus (SARS-CoV-2) is rapidly spreading across the globe, so the development of anti-SARS-CoV-2 agents is urgently needed. Angiotensin-converting enzyme 2 (ACE-2), a human receptor that facilitates entry of SARS-CoV-2, serves as a prominent target for drug discovery. In the present study, we have applied the bioinformatics approach for screening of a series of bioactive chemical compounds from Himalayan stinging nettle (Urtica dioica) as potent inhibitors of ACE-2 receptor (PDB ID: 1R4L). The molecular docking was applied to dock a set of representative compounds within the active site region of target receptor protein using 0.8 version of the PyRx virtual screen tool and analyzed by using discovery studio visualizer. Based on the highest binding affinity, 23 compounds were shortlisted as a lead molecule using molecular docking analysis. Among them, β-sitosterol was found with the highest binding affinity − 12.2 kcal/mol and stable interactions with the amino acid residues present on the active site of the ACE-2 receptor. Similarly, luteoxanthin and violaxanthin followed by rutin also displayed stronger binding efficiency. We propose these compounds as potential lead candidates for the development of target-specific therapeutic drugs against COVID-19.

Graphic abstract

Electronic supplementary material

The online version of this article (10.1007/s11030-020-10159-2) contains supplementary material, which is available to authorized users.

Repurposing Approved Drugs for Guiding COVID-19 Prophylaxis: A Systematic Review

The SARS-CoV-2 outbreak originally appeared in China in December 2019 and became a global pandemic in March 2020. This infectious disease has directly affected public health and the world economy. Several palliative therapeutic treatments and prophylaxis strategies have been used to control the progress of this viral infection, including pre-(PrEP) and post-exposure prophylaxis. On the other hand, research groups around the world are still studying novel drug prophylaxis and treatment using repurposing approaches, as well as vaccination options, which are in different pre-clinical and clinical testing phases. This systematic review evaluated 1,228 articles from the PubMed and Scopus indexing databases, following the Kitchenham bibliographic searching protocol, with the aim to list drug candidates, potentially approved to be used as new options for SARS-CoV-2 prophylaxis clinical trials and medical protocols. In searching protocol, we used the following keywords: "Covid-19 or SARS-CoV-2" or "Coronavirus or 2019 nCoV," "prophylaxis," "prophylactic," "pre-exposure," "COVID-19 or SARS-CoV-2 Chemoprophylaxis," "repurposed," "strategies," "clinical," "trials," "anti-SARS-CoV-2," "anti-covid-19," "Antiviral," "Therapy prevention in vitro," in cells "and" human testing. After all protocol steps, we selected 60 articles that included: 15 studies with clinical data, 22 studies that used in vitro experiments, seven studies using animal models, and 18 studies performed with in silico experiments. Additionally, we included more 22 compounds between FDA approved drugs and drug-like like molecules, which were tested in large-scale screenings, as well as those repurposed approved drugs with new mechanism of actions. The drugs selected in this review can assist clinical studies and medical guidelines on the rational repurposing of known antiviral drugs for COVID-19 prophylaxis.

Drug repurposing and cytokine management in response to COVID-19: A review

Coronavirus disease 2019 (COVID-19), the infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an aggressive disease that attacks the respiratory tract and has a higher fatality rate than seasonal influenza. The COVID-19 pandemic is a global health crisis, and no specific therapy or drug has been formally recommended for use against SARS-CoV-2 infection. In this context, it is a rational strategy to investigate the repurposing of existing drugs to use in the treatment of COVID-19 patients. In the meantime, the medical community is trialing several therapies that target various antiviral and immunomodulating mechanisms to use against the infection. There is no doubt that antiviral and supportive treatments are important in the treatment of COVID-19 patients, but anti-inflammatory therapy also plays a pivotal role in the management COVID-19 patients due to its ability to prevent further injury and organ damage or failure. In this review, we identified drugs that could modulate cytokines levels and play a part in the management of COVID-19. Several drugs that possess an anti-inflammatory profile in others illnesses have been studied in respect of their potential utility in the treatment of the hyperinflammation induced by SAR-COV-2 infection. We highlight a number of antivirals, anti-rheumatic, anti-inflammatory, antineoplastic and antiparasitic drugs that have been found to mitigate cytokine production and consequently attenuate the "cytokine storm" induced by SARS-CoV-2. Reduced hyperinflammation can attenuate multiple organ failure, and even reduce the mortality associated with severe COVID-19. In this context, despite their current unproven clinical efficacy in relation to the current pandemic, the repurposing of drugs with anti-inflammatory activity to use in the treatment of COVID-19 has become a topic of great interest.

Treatment of COVID-19 Patients with Prolonged Post-Symptomatic Viral Shedding with Leflunomide -- a Single-Center, Randomized, Controlled Clinical Trial

Objective

To evaluate the efficacy and safety of leflunomide, an approved dihydroorotate dehydrogenase inhibitor, to treat COVID-19 patients with prolonged post-symptomatic viral shedding.

Methods

We conducted a prospective, randomized, controlled, open-label trial involving hospitalized adult COVID-19 patients with prolonged PCR positivity. Patients were randomly assigned to receive either leflunomide (50 mg, q12h, three consecutive times, orally; then 20 mg, once daily for 8 days), in addition to nebulized interferon alpha 2a (IFN α-2a, 3 million IU each time, twice daily for 10 days), or nebulized IFN α-2a alone for 10 days. The primary end point was the duration of viral shedding.

Results

A total of 50 COVID-19 patients with prolonged PCR positivity were randomized into 2 groups; 26 were assigned to the leflunomide group, and 24 were assigned to the interferon alone group. Treatment with leflunomide was not associated with a difference from the interferon alone group in the duration of viral shedding (hazard ratio for negative RT-PCR, 0.70; 95% confidence interval, 0.391-1.256; P=0.186). In addition, the patients given leflunomide did not have a substantially shorter length of hospital stay than patients treated with interferon alone, with median (IQRs) durations of 29.0 (19.3-47.3) days and 33.0 (29.3-42.8) days, respectively, P=0.170. Two leflunomide recipients were unable to complete the full 10-day course of administration due to adverse events.

Conclusions

In COVID-19 patients with prolonged PCR positivity, no benefit in terms of the duration of viral shedding was observed with the combined treatment of leflunomide and IFN α-2a beyond IFN α-2a alone.

Cancer Management during COVID-19 Pandemic: Is Immune Checkpoint Inhibitors-Based Immunotherapy Harmful or Beneficial?

The coronavirus disease 2019 (COVID-19) is currently representing a global health threat especially for fragile individuals, such as cancer patients. It was demonstrated that cancer patients have an increased risk of developing a worse symptomatology upon severe acute respiratory syndrome associated coronavirus-2 (SARS-CoV-2) infection, often leading to hospitalization and intensive care. The consequences of this pandemic for oncology are really heavy, as the entire healthcare system got reorganized. Both oncologists and cancer patients are experiencing rescheduling of treatments and disruptions of appointments with a concurrent surge of fear and stress. In this review all the up-to-date findings, concerning the association between COVID-19 and cancer, are reported. A remaining very debated question regards the use of an innovative class of anti-cancer molecules, the immune checkpoint inhibitors (ICIs), given their modulating effects on the immune system. For that reason, administration of ICIs to cancer patients represents a question mark during this pandemic, as its correlation with COVID-19-associated risks is still under investigation. Based on the mechanisms of action of ICIs and the current evidence, we suggest that ICIs not only can be safely administered to cancer patients, but they might even be beneficial in COVID-19-positive cancer patients, by exerting an immune-stimulating action.

Racial Disparities-Associated COVID-19 Mortality among Minority Populations in the US

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a betacoronavirus that causes the novel coronavirus disease 2019 (COVID-19), is highly transmissible and pathogenic for humans and may cause life-threatening disease and mortality, especially in individuals with underlying comorbidities. First identified in an outbreak in Wuhan, China, COVID-19 is affecting more than 185 countries and territories around the world, with more than 15,754,651 confirmed cases and more than 640,029 deaths. Since December 2019, SARS-CoV-2 transmission has become a global threat, which includes confirmed cases in all 50 states within the United States (US). As of 25 July 2020, the Johns Hopkins Whiting School of Engineering Center for Systems Science and Engineering reports more than 4,112,651 cases and 145,546 deaths. To date, health disparities are associated with COVID-19 mortality among underserved populations. Here, the author explores potential underlying reasons for reported disproportionate, increased risks of mortality among African Americans and Hispanics/Latinos with COVID-19 compared with non-Hispanic Whites. The author examines the underlying clinical implications that may predispose minority populations and the adverse clinical outcomes that may contribute to increased risk of mortality. Government and community-based strategies to safeguard minority populations at risk for increased morbidity and mortality are essential. Underserved populations living in poverty with limited access to social services across the US are more likely to have underlying medical conditions and are among the most vulnerable. Societal and cultural barriers for ethnic minorities to achieve health equity are systemic issues that may be addressed only through shifts in governmental policies, producing long-overdue, substantive changes to end health care inequities.