Drug repurposing strategies for COVID-19

Repurposing Anthelmintic Drugs for COVID-19 Treatment: A Comprehensive Meta-Analysis of Randomized Clinical Trials on Ivermectin and Mebendazole

Background: The COVID-19 pandemic necessitated the urgent exploration of therapeutic options, including drug repurposing. Anthelmintic drugs such as ivermectin and mebendazole have garnered interest due to their potential antiviral and immunomodulatory properties. However, conflicting evidence from randomized clinical trials (RCTs) necessitates a comprehensive meta-analysis to determine their efficacy and safety in COVID-19 management. Objective: This meta-analysis evaluates the clinical efficacy of ivermectin and mebendazole in treating COVID-19 by analyzing their impact on viral clearance, symptom resolution, hospitalization duration, and safety profiles. Methods: A systematic search of Scopus, PubMed, Embase, and the Cochrane Library was conducted following PRISMA guidelines to identify RCTs published up to February 2025. Eligible studies included adult patients with confirmed COVID-19 who received ivermectin or mebendazole compared with a placebo or standard of care. Data extraction and risk of bias assessment were performed using the Cochrane Risk of Bias Tool. Statistical heterogeneity was evaluated using the I2 statistic, and pooled effect sizes were calculated for primary clinical outcomes. Results: Twenty-three RCTs (n = 12,345) were included, with twenty-one studies on ivermectin and two on mebendazole. The pooled analysis suggested no statistically significant improvement in viral clearance (p = 0.39), hospitalization duration (p = 0.15), or symptom resolution (p = 0.08) with ivermectin or mebendazole. However, individual studies indicated potential benefits, particularly for mebendazole, in reducing viral load and inflammation. Both drugs exhibited favorable safety profiles, with no significant increase in adverse events. Conclusions: The promising propensities observed in selected studies underscore the potential of ivermectin and mebendazole as adjunct therapies for COVID-19. With well-established safety profiles, immunomodulatory effects, and affordability, these drugs present strong candidates for further exploration. Advancing research through well-designed, large-scale RCTs will help unlock their full therapeutic potential and expand treatment options in the fight against COVID-19.

Drug Repositioning: A Monetary Stratagem to Discover a New Application of Drugs

Drug repurposing, also referred to as drug repositioning or drug reprofiling, is a scientific approach to the detection of any new application for an already approved or investigational drug. It is a useful policy for the invention and development of new pharmacological or therapeutic applications of different drugs. The strategy has been known to offer numerous advantages over developing a completely novel drug for certain problems. Drug repurposing has numerous methodologies that can be categorized as target-oriented, drug-oriented, and problem-oriented. The choice of the methodology of drug repurposing relies on the accessible information about the drug molecule and like pharmacokinetic, pharmacological, physicochemical, and toxicological profile of the drug. In addition, molecular docking studies and other computer-aided methods have been known to show application in drug repurposing. The variation in dosage for original target diseases and novel diseases presents a challenge for researchers of drug repurposing in present times. The present review critically discusses the drugs repurposed for cancer, covid-19, Alzheimer's, and other diseases, strategies, and challenges of drug repurposing. Moreover, regulatory perspectives related to different countries like the United States (US), Europe, and India have been delineated in the present review.

Synthesis, Docking Study of Some Novel Chromeno[4',3'-b]Pyrano [6,5-d]Pyrimidine Derivatives Against COVID-19 Main Protease (Mpro) (6LU7, 6M03)

AIMS

In this work, some new chromeno[4',3'-b]pyrano[6,5-d]pyrimidines,3-amino and 3-methyl-5-aryl-4-imino-5(H)-chromeno[4',3'-b]pyrano[6,5-d]pyrimidine-6-ones derivatives were synthesized.

BACKGROUND

Chromenopyrimidines have attracted significant attention recently because of their activities, such as antiviral and cytotoxic activity.

OBJECTIVE

All synthesized compounds were characterized using IR, 1H-NMR, Mass Spectroscopy, and elemental analysis data.

METHODS

Molecular docking studies were carried out to determine the inhibitory action of studied ligands against the Main Protease (6LU7, 6m03) of coronavirus (COVID-19). Moreover, the Lipinski Rule parameters were calculated for the synthesized compounds.

RESULTS

The result of the docking studies showed a significant inhibitory action against the Main protease (Mpro) of SARS-CoV-2, and the binding energy (ΔG) values of the ligands against the protein (6LU7, 6M03) are -7.8 to -9.9 Kcal/mole.

CONCLUSION

It may conclude that some ligands were likely to be considered lead-like against the main protease of SARS-CoV-2.

Therapeutic Potential of Bioactive Compounds from Edible Mushrooms to Attenuate SARS-CoV-2 Infection and Some Complications of Coronavirus Disease (COVID-19)

The novel severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a highly infectious positive RNA virus, has spread from its epicenter to other countries with increased mortality and morbidity. Its expansion has hampered humankind's social, economic, and health realms to a large extent. Globally, investigations are underway to understand the complex pathophysiology of coronavirus disease (COVID-19) induced by SARS-CoV-2. Though numerous therapeutic strategies have been introduced to combat COVID-19, none are fully proven or comprehensive, as several key issues and challenges remain unresolved. At present, natural products have gained significant momentum in treating metabolic disorders. Mushrooms have often proved to be the precursor of various therapeutic molecules or drug prototypes. The plentiful bioactive macromolecules in edible mushrooms, like polysaccharides, proteins, and other secondary metabolites (such as flavonoids, polyphenols, etc.), have been used to treat multiple diseases, including viral infections, by traditional healers and the medical fraternity. Some edible mushrooms with a high proportion of therapeutic molecules are known as medicinal mushrooms. In this review, an attempt has been made to highlight the exploration of bioactive molecules in mushrooms to combat the various pathophysiological complications of COVID-19. This review presents an in-depth and critical analysis of the current therapies against COVID-19 versus the potential of natural anti-infective, antiviral, anti-inflammatory, and antithrombotic products derived from a wide range of easily sourced mushrooms and their bioactive molecules.

COVID-19 therapeutics: Clinical application of repurposed drugs and futuristic strategies for target-based drug discovery

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) causes the complicated disease COVID-19. Clinicians are continuously facing huge problems in the treatment of patients, as COVID-19-specific drugs are not available, hence the principle of drug repurposing serves as a one-and-only hope. Globally, the repurposing of many drugs is underway; few of them are already approved by the regulatory bodies for their clinical use and most of them are in different phases of clinical trials. Here in this review, our main aim is to discuss in detail the up-to-date information on the target-based pharmacological classification of repurposed drugs, the potential mechanism of actions, and the current clinical trial status of various drugs which are under repurposing since early 2020. At last, we briefly proposed the probable pharmacological and therapeutic drug targets that may be preferred as a futuristic drug discovery approach in the development of effective medicines.

Evaluating Risk: Benefit Ratio of Fat-Soluble Vitamin Supplementation to SARS-CoV-2-Infected Autoimmune and Cancer Patients: Do Vitamin-Drug Interactions Exist?

COVID-19 is a recent pandemic that mandated the scientific society to provide effective evidence-based therapeutic approaches for the prevention and treatment for such a global threat, especially to those patients who hold a higher risk of infection and complications, such as patients with autoimmune diseases and cancer. Recent research has examined the role of various fat-soluble vitamins (vitamins A, D, E, and K) in reducing the severity of COVID-19 infection. Studies showed that deficiency in fat-soluble vitamins abrogates the immune system, thus rendering individuals more susceptible to COVID-19 infection. Moreover, another line of evidence showed that supplementation of fat-soluble vitamins during the course of infection enhances the viral clearance episode by promoting an adequate immune response. However, more thorough research is needed to define the adequate use of vitamin supplements in cancer and autoimmune patients infected with COVID-19. Moreover, it is crucial to highlight the vitamin-drug interactions of the COVID-19 therapeutic modalities and fat-soluble vitamins. With an emphasis on cancer and autoimmune patients, the current review aims to clarify the role of fat-soluble vitamins in SARS-CoV-2 infection and to estimate the risk-to-benefit ratio of a fat-soluble supplement administered to patients taking FDA-approved COVID-19 medications such as antivirals, anti-inflammatory, receptor blockers, and monoclonal antibodies.

The failure of drug repurposing for COVID-19 as an effect of excessive hypothesis testing and weak mechanistic evidence

The current strategy of searching for an effective treatment for COVID-19 relies mainly on repurposing existing therapies developed to target other diseases. Conflicting results have emerged in regard to the efficacy of several tested compounds but later results were negative. The number of conducted and ongoing trials and the urgent need for a treatment pose the risk that false-positive results will be incorrectly interpreted as evidence for treatments' efficacy and a ground for drug approval. Our purpose is twofold. First, we show that the number of drug-repurposing trials can explain the false-positive results. Second, we assess the evidence for treatments' efficacy from the perspective of evidential pluralism and argue that considering mechanistic evidence is particularly needed in cases when the evidence from clinical trials is conflicting or of low quality. Our analysis is an application of the program of Evidence Based Medicine Plus (EBM+) to the drug repurposing trials for COVID. Our study shows that if decision-makers applied EBM+, authorizing the use of ineffective treatments would be less likely. We analyze the example of trials assessing the efficacy of hydroxychloroquine as a treatment for COVID-19 and mechanistic evidence in favor of and against its therapeutic power to draw a lesson for decision-makers and drug agencies on how excessive hypothesis testing can lead to spurious findings and how studying negative mechanistic evidence can be helpful in discriminating genuine from spurious results.

Electrochemical Sensing of Favipiravir with an Innovative Water-Dispersible Molecularly Imprinted Polymer Based on the Bimetallic Metal-Organic Framework: Comparison of Morphological Effects

Molecularly imprinted polymers (MIPs) are widely used as modifiers in electrochemical sensors due to their high sensitivity and promise of inexpensive mass manufacturing. Here, we propose and demonstrate a novel MIP-sensor that can measure the electrochemical activity of favipiravir (FAV) as an antiviral drug, thereby enabling quantification of the concentration of FAV in biological and river water samples and in real-time. MOF nanoparticles’ application with various shapes to determine FAV at nanomolar concentrations was described. Two different MOF nanoparticle shapes (dodecahedron and sheets) were systematically compared to evaluate the electrochemical performance of FAV. After carefully examining two different morphologies of MIP-Co-Ni@MOF, the nanosheet form showed a higher performance and efficiency than the nanododecahedron. When MIP-Co/Ni@MOF-based and NIP-Co/Ni@MOF electrodes (nanosheets) were used instead, the minimum target concentrations detected were 7.5 × 10−11 (MIP-Co-Ni@MOF) and 8.17 × 10−9 M (NIP-Co-Ni@MOF), respectively. This is a significant improvement (>102), which is assigned to the large active surface area and high fraction of surface atoms, increasing the amount of greater analyte adsorption during binding. Therefore, water-dispersible MIP-Co-Ni@MOF nanosheets were successfully applied for trace-level determination of FAV in biological and water samples. Our findings seem to provide useful guidance in the molecularly imprinted polymer design of MOF-based materials to help establish quantitative rules in designing MOF-based sensors for point of care (POC) systems.

A comprehensive review of adverse events to drugs used in COVID-19 patients: Recent clinical evidence

BACKGROUND

Since the breakthrough of the pandemic, several drugs have been used to treat COVID-19 patients. This review aims to gather information on adverse events (AE) related to most drugs used in this context.

METHODS

We performed a literature search to find articles that contained information about AE in COVID-19 patients. We analysed and reviewed the most relevant studies in the Medline (via PubMed), Scopus and Web of Science. The most frequent AE identified were grouped in our qualitative analysis by System Organ Class (SOC), the highest level of the MedDRA medical terminology for each of the drugs studied.

RESULTS

The most frequent SOCs among the included drugs are investigations (n = 7 drugs); skin and subcutaneous tissue disorders (n = 5 drugs); and nervous system disorders, infections and infestations, gastrointestinal disorders, hepatobiliary disorders, and metabolism and nutrition disorders (n = 4 drugs). Other SOCs also emerged, such as general disorders and administration site conditions, renal and urinary disorders, vascular disorders and cardiac disorders (n = 3 drugs). Less frequent SOC were eye disorders, respiratory, thoracic and mediastinal disorders, musculoskeletal and connective tissue disorders, and immune system disorders (n = 2 drugs). Psychiatric disorders, and injury, poisoning and procedural complications were also reported (n = 1 drug).

CONCLUSIONS

Some SOCs seem to be more frequent than others among the COVID-19 drugs included, although neither of the studies included reported causality analysis. For that purpose, further clinical studies with robust methodologies, as randomised controlled trials, should be designed and performed.

In Silico Study of Alkaloids: Neferine and Berbamine Potentially Inhibit the SARS-CoV-2 RNA-Dependent RNA Polymerase

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19, has been a global concern. While there have been some vaccines and drugs, the rapid emergence of variants due to mutations has threatened public health. As the de novo drug development process is expensive and time-consuming, repurposing existing antiviral drugs against SARS-CoV-2 is an alternative and promising approach to mitigate the current situation. Several studies have indicated that some natural products exhibit inhibitory activities against SARS-CoV-2. This study is aimed at analyzing the potential of natural alkaloids, using various computational tools, as drug candidates against SARS-CoV-2. The molecular docking analysis predicted that naturally occurring alkaloids can bind with RNA-dependent RNA-polymerase (RdRP). The QSAR analysis was conducted by using the way2drug/PASS online web resource, and the pharmacokinetics and toxicity properties of these alkaloids were predicted using pkCSM, SwissADME, and ProTox-II webserver. Among the different alkaloids studied, neferine and berbamine were repurposed as potential drug candidates based on their binding affinity and interactions with RdRP. Further, molecular dynamics simulation of 90 ns revealed the conformational stability of the neferine-RdRP complex.

Non-effectiveness of Ivermectin on Inpatients and Outpatients With COVID-19; Results of Two Randomized, Double-Blinded, Placebo-Controlled Clinical Trials

Background

Ivermectin which was widely considered as a potential treatment for COVID-19, showed uncertain clinical benefit in many clinical trials. Performing large-scale clinical trials to evaluate the effectiveness of this drug in the midst of the pandemic, while difficult, has been urgently needed.

Methods

We performed two large multicenter randomized, double-blind, placebo-controlled clinical trials evaluating the effectiveness of ivermectin in treating inpatients and outpatients with COVID-19 infection. The intervention group received ivermectin, 0.4mg/kg of body weight per day for 3 days. In the control group, placebo tablets were used for 3 days.

Results

Data for 609 inpatients and 549 outpatients were analyzed. In hospitalized patients, complete recovery was significantly higher in the ivermectin group (37%) compared to placebo group (28%; RR, 1.32 [95% CI, 1.04–1.66]; p-value = 0.02). On the other hand, the length of hospital stay was significantly longer in the ivermectin group with a mean of 7.98 ± 4.4 days compared to the placebo receiving group with a mean of 7.16 ± 3.2 days (RR, 0.80 [95% CI, 0.15–1.45]; p-value = 0.02). In outpatients, the mean duration of fever was significantly shorter (2.02 ± 0.11 days) in the ivermectin group versus (2.41 ± 0.13 days) placebo group with p value = 0.020. On the day seventh of treatment, fever (p-value = 0.040), cough (p-value = 0.019), and weakness (p-value = 0.002) were significantly higher in the placebo group compared to the ivermectin group. Among all outpatients, 7% in ivermectin group and 5% in placebo group needed to be hospitalized (RR, 1.36 [95% CI, 0.65–2.84]; p-value = 0.41). Also, the result of RT-PCR on day five after treatment was negative for 26% of patients in the ivermectin group versus 32% in the placebo group (RR, 0.81 [95% CI, 0.60–1.09]; p-value = 0.16).

Conclusion

Our data showed, ivermectin, compared with placebo, did not have a significant potential effect on clinical improvement, reduced admission in ICU, need for invasive ventilation, and death in hospitalized patients; likewise, no evidence was found to support the prescription of ivermectin on recovery, reduced hospitalization and increased negative RT-PCR assay for SARS-CoV-2 5 days after treatment in outpatients. Our findings do not support the use of ivermectin to treat mild to severe forms of COVID-19.

Clinical Trial Registration

www.irct.ir IRCT20111224008507N5 and IRCT20111224008507N4.

Repurposing of antiviral drugs for COVID-19 and impact of repurposed drugs on the nervous system

The recent pandemic, Coronavirus Disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has devastated humanity and is continuing to threaten us. Due to the high transmissibility of this pathogen, researchers are still trying to cope with the treatment and prevention of this disease. Few of them were successful in finding cure for COVID-19 by including repurposed drugs in the treatment. In such pandemic situations, when it is nearly impossible to design and implement a new drug target, previously designed antiviral drugs could help against novel viruses, referred to as drug repurposing/redirecting/repositioning or re-profiling. This review describes the current landscape of the repurposing of antiviral drugs for COVID-19 and the impact of these drugs on our nervous system. In some cases, specific antiviral therapy has been notably associated with neurological toxicity, characterized by peripheral neuropathy, neurocognitive and neuropsychiatric effects within the central nervous system (CNS).

A review on drug repurposing in COVID-19: from antiviral drugs to herbal alternatives

BACKGROUND

COVID-19 is an illness caused by severe acute respiratory syndrome coronavirus 2. Due to its rapid spread, in March 2020 the World Health Organization (WHO) declared pandemic. Since the outbreak of pandemic many governments, scientists, and institutions started to work on new vaccines and finding of new and repurposing drugs. Drug repurposing is an excellent option for discovery of already used drugs, effective against COVID-19, lowering the cost of production, and shortening the period of delivery, especially when preclinical safety studies have already been performed. There are many approved drugs that showed significant results against COVID-19, like ivermectin and hydrochloroquine, including alternative treatment options against COVID-19, utilizing herbal medicine.

SHORT CONCLUSION

This article summarized 11 repurposing drugs, their positive and negative health implications, along with traditional herbal alternatives, that harvest strong potential in efficient treatments options against COVID-19, with small or no significant side effects. Out of 11 repurposing drugs, four drugs are in status of emergency approval, most of them being in phase IV clinical trials. The first repurposing drug approved for clinical usage is remdesivir, whereas chloroquine and hydrochloroquine approval for emergency use was revoked by FDA for COVID-19 treatment in June 2020.

How can natural language processing help model informed drug development?: a review

Objective

To summarize applications of natural language processing (NLP) in model informed drug development (MIDD) and identify potential areas of improvement.

Materials and Methods

Publications found on PubMed and Google Scholar, websites and GitHub repositories for NLP libraries and models. Publications describing applications of NLP in MIDD were reviewed. The applications were stratified into 3 stages: drug discovery, clinical trials, and pharmacovigilance. Key NLP functionalities used for these applications were assessed. Programming libraries and open-source resources for the implementation of NLP functionalities in MIDD were identified.

Results

NLP has been utilized to aid various processes in drug development lifecycle such as gene-disease mapping, biomarker discovery, patient-trial matching, adverse drug events detection, etc. These applications commonly use NLP functionalities of named entity recognition, word embeddings, entity resolution, assertion status detection, relation extraction, and topic modeling. The current state-of-the-art for implementing these functionalities in MIDD applications are transformer models that utilize transfer learning for enhanced performance. Various libraries in python, R, and Java like huggingface, sparkNLP, and KoRpus as well as open-source platforms such as DisGeNet, DeepEnroll, and Transmol have enabled convenient implementation of NLP models to MIDD applications.

Discussion

Challenges such as reproducibility, explainability, fairness, limited data, limited language-support, and security need to be overcome to ensure wider adoption of NLP in MIDD landscape. There are opportunities to improve the performance of existing models and expand the use of NLP in newer areas of MIDD.

Conclusions

This review provides an overview of the potential and pitfalls of current NLP approaches in MIDD.

Potential therapeutic options for COVID-19: an update on current evidence

SARS-CoV-2, a novel coronavirus, is the agent responsible for the COVID-19 pandemic and is a major public health concern nowadays. The rapid and global spread of this coronavirus leads to an increase in hospitalizations and thousands of deaths in many countries. To date, great efforts have been made worldwide for the efficient management of this crisis, but there is still no effective and specific treatment for COVID-19. The primary therapies to treat the disease are antivirals, anti-inflammatories and respiratory therapy. In addition, antibody therapies currently have been a many active and essential part of SARS-CoV-2 infection treatment. Ongoing trials are proposed different therapeutic options including various drugs, convalescent plasma therapy, monoclonal antibodies, immunoglobulin therapy, and cell therapy. The present study summarized current evidence of these therapeutic approaches to assess their efficacy and safety for COVID-19 treatment. We tried to provide comprehensive information about the available potential therapeutic approaches against COVID-19 to support researchers and physicians in any current and future progress in treating COVID-19 patients.

Pharmacophore screening to identify natural origin compounds to target RNA-dependent RNA polymerase (RdRp) of SARS-CoV2

Several existing drugs have gained initial consideration due to their therapeutic characteristics against COVID-19 (Corona Virus Disease 2019). Hydroxychloroquine (HCQ) was proposed as possible therapy for shortening the duration of COVID-19, but soon after this, it was discarded. Similarly, known antiviral compounds were also proposed and investigated to treat COVID-19. We report a pharmacophore screening using essential chemical groups derived from HCQ and known antivirals to search a natural compound chemical space. Molecular docking of HCQ under physiological condition with spike protein, 3C-like protease (3CLpro), and RNA-dependent RNA polymerase (RdRp) of SARS-CoV2 showed - 8.52 kcal/mole binding score with RdRp, while the other two proteins showed relatively weaker binding affinity. Docked complex of RdRp-HCQ is further examined using 100 ns molecular dynamic simulation. Docking and simulation study confirmed active chemical moieties of HCQ, treated as 6-point pharmacophore to screen ZINC natural compound database. Pharmacophore screening resulted in the identification of potent hit molecule [(3S,3aR,6R,6aS)-3-(5-phenylsulfanyltetrazol-1-yl)-2,3,3a,5,6,6a-hexahydrofuro[3,2-b]furan-6-yl]N-naphthalen-ylcarbamate from natural compound library. Additionally, a set of antiviral compounds with similar chemical scaffolds are also used to design a separate ligand-based pharmacophore screening. Antiviral pharmacophore screening produced a potent hit 4-[(1,5-dimethyl-3-oxo-2-phenylpyrazol-4-yl)-(2-hydroxyphenyl)methyl]-1,5-dimethyl-2-phenylpyrazol-3-one containing essential moieties that showed affinity towards RdRp. Further, both these screened compounds are docked (- 8.69 and - 8.86 kcal/mol) and simulated with RdRp protein for 100 ns in explicit solvent medium. They bind at the active site of RdRp and form direct/indirect interaction with ASP618, ASP760, and ASP761 catalytic residues of the protein. Successively, their molecular mechanics Poisson Boltzmann surface area (MMPBSA) binding energies are calculated over the simulation trajectory to determine the dynamic atomistic interaction details. Overall, this study proposes two key natural chemical moieties: (a) tetrazol and (b) phenylpyrazol that can be investigated as a potential chemical group to design inhibitors against SARS-CoV2 RdRp.

Repurposing – second life for drugs

Drug repurposing refers to finding new indications for existing drugs. The paradigm shift from traditional drug discovery to drug repurposing is driven by the fact that new drug pipelines are getting dried up because of mounting Research & Development (R&D) costs, long timeline for new drug development, low success rate for new molecular entities, regulatory hurdles coupled with revenue loss from patent expiry and competition from generics. Anaemic drug pipelines along with increasing demand for newer effective, cheaper, safer drugs and unmet medical needs call for new strategies of drug discovery and, drug repurposing seems to be a promising avenue for such endeavours. Drug repurposing strategies have progressed over years from simple serendipitous observations to more complex computational methods in parallel with our ever-growing knowledge on drugs, diseases, protein targets and signalling pathways but still the knowledge is far from complete. Repurposed drugs too have to face many obstacles, although lesser than new drugs, before being successful.

A Comprehensive Review about the Molecular Structure of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2): Insights into Natural Products against COVID-19

In 2019, the world suffered from the emergence of COVID-19 infection, one of the most difficult pandemics in recent history. Millions of confirmed deaths from this pandemic have been reported worldwide. This disaster was caused by SARS-CoV-2, which is the last discovered member of the family of Coronaviridae. Various studies have shown that natural compounds have effective antiviral properties against coronaviruses by inhibiting multiple viral targets, including spike proteins and viral enzymes. This review presents the classification and a detailed explanation of the SARS-CoV-2 molecular characteristics and structure-function relationships. We present all currently available crystal structures of different SARS-CoV-2 proteins and emphasized on the crystal structure of different virus proteins and the binding modes of their ligands. This review also discusses the various therapeutic approaches for COVID-19 treatment and available vaccinations. In addition, we highlight and compare the existing data about natural compounds extracted from algae, fungi, plants, and scorpion venom that were used as antiviral agents against SARS-CoV-2 infection. Moreover, we discuss the repurposing of select approved therapeutic agents that have been used in the treatment of other viruses.

SARS-CoV-2 spike protein and RNA dependent RNA polymerase as targets for drug and vaccine development: A review

The present pandemic has posed a crisis to the economy of the world and the health sector. Therefore, the race to expand research to understand some good molecular targets for vaccine and therapeutic development for SARS-CoV-2 is inevitable. The newly discovered coronavirus 2019 (COVID-19) is a positive sense, single-stranded RNA, and enveloped virus, assigned to the beta CoV genus. The virus (SARS-CoV-2) is more infectious than the previously detected coronaviruses (MERS and SARS). Findings from many studies have revealed that S protein and RdRp are good targets for drug repositioning, novel therapeutic development (antibodies and small molecule drugs), and vaccine discovery. Therapeutics such as chloroquine, convalescent plasma, monoclonal antibodies, spike binding peptides, and small molecules could alter the ability of S protein to bind to the ACE-2 receptor, and drugs such as remdesivir (targeting SARS-CoV-2 RdRp), favipir, and emetine could prevent SASR-CoV-2 RNA synthesis. The novel vaccines such as mRNA1273 (Moderna), 3LNP-mRNAs (Pfizer/BioNTech), and ChAdOx1-S (University of Oxford/Astra Zeneca) targeting S protein have proven to be effective in combating the present pandemic. Further exploration of the potential of S protein and RdRp is crucial in fighting the present pandemic.

Clinical Efficacy and Safety of Antiviral Drugs in the Extended Use against COVID-19: What We Know So Far

Human beings around the globe have been suffering from a devastating novel pandemic and public health emergency, coronavirus disease 2019 (COVID-19), for more than one and a half years due to the deadly and highly pathogenic severe acute respiratory coronavirus 2 (SARS-CoV-2) infection worldwide. Notably, no effective treatment strategy has been approved for the complete recovery of COVID-19 patients, though several vaccines have been rolled out around the world upon emergency use authorization. After the emergence of the COVID-19 outbreak globally, plenty of clinical investigations commenced to screen the safety and efficacy of several previously approved drugs to be repurposed against the SARS-CoV-2 pathogen. This concise review aims at exploring the current status of the clinical efficacy and safety profile of several antiviral medications for the treatment of patients with COVID-19 and other respiratory complications caused by SARS-CoV-2 infection. The paper covers all kinds of human studies (January 2020 to June 2021) except case reports/series to highlight the clear conclusion based on the current clinical evidence. Among the promising repositioned antivirals, remdesivir has been recommended in critical conditions to mitigate the fatality rate and improve clinical conditions. In addition, boosting the immune system is believed to be beneficial in treating COVID-19 patients, so interferon type I might exert immunomodulation through its antiviral effects by stimulating interferon-stimulated gene (ISG). However, more extensive clinical studies covering all ethnic groups globally are warranted based on current data to better understand the clinical efficacy of the currently proposed repurposed drugs against COVID-19.

Could Nanotechnology Help to End the Fight Against COVID-19? Review of Current Findings, Challenges and Future Perspectives

A serious viral infectious disease was introduced to the globe by the end of 2019 that was seen primarily from China, but spread worldwide in a few months to be a pandemic. Since then, accurate prevention, early detection, and effective treatment strategies are not yet outlined. There is no approved drug to counter its worldwide transmission. However, integration of nanostructured delivery systems with the current management strategies has promised a pronounced opportunity to tackle the pandemic. This review addressed the various promising nanotechnology-based approaches for the diagnosis, prevention, and treatment of the pandemic. The pharmaceutical, pharmacoeconomic, and regulatory aspects of these systems with currently achieved or predicted beneficial outcomes, challenges, and future perspectives are also highlighted.

Current understanding on molecular drug targets and emerging treatment strategy for novel coronavirus-19

SARS-CoV-2 is an enveloped positive-sense RNA virus, contain crown-like spikes on its surface, exceptional of large RNA genome, and a special replication machinery. Common symptoms of SARS-CoV-2 include cough, common cold, fever, sore throat, and a variety of severe acute respiratory disease (SARD) such as pneumonia. SARS-CoV-2 infects epithelial cells, T-cells, macrophages, and dendritic cells and also influences the production and implantation of pro-inflammatory cytokines and chemokines. Repurposing of various drugs during this emergency condition can reduce the rate of mortality as well as time and cost. Two druggable protein and enzyme targets have been selected in this review article due to their crucial role in the viral life cycle. The eukaryotic translation initiation factor (eIF4A), cyclophilin, nucleocapsid protein, spike protein, Angiotensin-converting enzyme 2 (ACE2), 3-chymotrypsin-like cysteine protease (3CLpro), and RNA-dependent RNA polymerase (RdRp) play significant role in early and late phase of SARS-CoV-2 replication and translation. This review paper is based on the rationale of inhibiting of various SARS-CoV-2 proteins and enzymes as novel therapeutic approaches for the management and treatment of patients with SARS-CoV-2 infection. We also discussed the structural and functional relationship of different proteins and enzymes to develop therapeutic approaches for novel coronavirus SARS-CoV-2.

Detection of significant antiviral drug effects on COVID-19 with reasonable sample sizes in randomized controlled trials: A modeling study

BACKGROUND

Development of an effective antiviral drug for Coronavirus Disease 2019 (COVID-19) is a global health priority. Although several candidate drugs have been identified through in vitro and in vivo models, consistent and compelling evidence from clinical studies is limited. The lack of evidence from clinical trials may stem in part from the imperfect design of the trials. We investigated how clinical trials for antivirals need to be designed, especially focusing on the sample size in randomized controlled trials.

METHODS AND FINDINGS

A modeling study was conducted to help understand the reasons behind inconsistent clinical trial findings and to design better clinical trials. We first analyzed longitudinal viral load data for Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) without antiviral treatment by use of a within-host virus dynamics model. The fitted viral load was categorized into 3 different groups by a clustering approach. Comparison of the estimated parameters showed that the 3 distinct groups were characterized by different virus decay rates (p-value < 0.001). The mean decay rates were 1.17 d-1 (95% CI: 1.06 to 1.27 d-1), 0.777 d-1 (0.716 to 0.838 d-1), and 0.450 d-1 (0.378 to 0.522 d-1) for the 3 groups, respectively. Such heterogeneity in virus dynamics could be a confounding variable if it is associated with treatment allocation in compassionate use programs (i.e., observational studies). Subsequently, we mimicked randomized controlled trials of antivirals by simulation. An antiviral effect causing a 95% to 99% reduction in viral replication was added to the model. To be realistic, we assumed that randomization and treatment are initiated with some time lag after symptom onset. Using the duration of virus shedding as an outcome, the sample size to detect a statistically significant mean difference between the treatment and placebo groups (1:1 allocation) was 13,603 and 11,670 (when the antiviral effect was 95% and 99%, respectively) per group if all patients are enrolled regardless of timing of randomization. The sample size was reduced to 584 and 458 (when the antiviral effect was 95% and 99%, respectively) if only patients who are treated within 1 day of symptom onset are enrolled. We confirmed the sample size was similarly reduced when using cumulative viral load in log scale as an outcome. We used a conventional virus dynamics model, which may not fully reflect the detailed mechanisms of viral dynamics of SARS-CoV-2. The model needs to be calibrated in terms of both parameter settings and model structure, which would yield more reliable sample size calculation.

CONCLUSIONS

In this study, we found that estimated association in observational studies can be biased due to large heterogeneity in viral dynamics among infected individuals, and statistically significant effect in randomized controlled trials may be difficult to be detected due to small sample size. The sample size can be dramatically reduced by recruiting patients immediately after developing symptoms. We believe this is the first study investigated the study design of clinical trials for antiviral treatment using the viral dynamics model.

Coronavirus genomic nsp14-ExoN, structure, role, mechanism, and potential application as a drug target

The recent coronavirus disease 2019 (COVID-19), causing a global pandemic with devastating effects on healthcare and social-economic systems, has no special antiviral therapies available for human coronaviruses (CoVs). The severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) possesses a nonstructural protein (nsp14), with amino-terminal domain coding for proofreading exoribonuclease (ExoN) that is required for high-fidelity replication. The ability of CoVs during genome replication and transcription to proofread and exclude mismatched nucleotides has long hindered the development of anti-CoV drugs. The resistance of SARS-CoV-2 to antivirals, especially nucleoside analogs (NAs), shows the need to identify new CoV inhibition targets. Therefore, this review highlights the importance of nsp14-ExoN as a target for inhibition. Also, nucleoside analogs could be used in combination with existing anti-CoV therapeutics to target the proofreading mechanism.

Guiding axes for drug safety management of pharmacovigilance centres during the COVID-19 era

The COVID-19 pandemic presents several challenges to the organisation and workflow of pharmacovigilance centres as a result of the massive increase in reports, the need for quick detection, processing and reporting of safety issues and the management of these within the context of lack of complete information on the disease. Pharmacovigilance centres permanently monitor the safety profile of medicines, ensuring risk management to evaluate the benefit-risk relationship. However, traditional pharmacovigilance approaches of spontaneous reporting, are not suitable in the context of a pandemic; the scientific community and regulators need information on a near real-time point. The aim of this commentary is to suggest six interrelated multidimensional guiding axes for drug safety management by pharmacovigilance centres during the COVID-19 pandemic. This working plan can increase knowledge on COVID-19 and associated therapeutic approaches, support decisions by the regulatory authorities, oppose fake news and promote more efficient public health protection.

Identification of potential COVID-19 main protease inhibitors using structure-based pharmacophore approach, molecular docking and repurposing studies

The current outbreak of novel coronavirus (COVID-19) infections urges the need to identify potential therapeutic agents. Therefore, the repurposing of FDA-approved drugs against today's diseases involves the use of de-risked compounds with potentially lower costs and shorter development timelines. In this study, the recently resolved X-ray crystallographic structure of COVID-19 main protease (Mpro) was used to generate a pharmacophore model and to conduct a docking study to capture antiviral drugs as new promising COVID-19 main protease inhibitors. The developed pharmacophore successfully captured five FDA-approved antiviral drugs (lopinavir, remdesivir, ritonavir, saquinavir and raltegravir). The five drugs were successfully docked into the binding site of COVID-19 Mpro and showed several specific binding interactions that were comparable to those tying the co-crystallized inhibitor X77 inside the binding site of COVID-19 Mpro. Three of the captured drugs namely, remdesivir, lopinavir and ritonavir, were reported to have promising results in COVID-19 treatment and therefore increases the confidence in our results. Our findings suggest an additional possible mechanism of action for remdesivir as an antiviral drug inhibiting COVID-19 Mpro. Additionally, a combination of structure-based pharmacophore modeling with a docking study is expected to facilitate the discovery of novel COVID-19 Mpro inhibitors.

A large-scale computational screen identifies strong potential inhibitors for disrupting SARS-CoV-2 S-protein and human ACE2 interaction

SARS-CoV-2 has infected millions of individuals across the globe and has killed over 2.7 million people. Even though vaccines against this virus have recently been introduced, the antibody generated in the process has been reported to decline quickly. This can reduce the efficacy of vaccines over time and can result in re-infections. Thus, drugs that are effective against COVID-19 can provide a second line of defence and can prevent occurrence of the severe form of the disease. The interaction between SARS-CoV2 S-protein and human ACE2 (hACE2) is essential for the infection of the virus. Thus, drugs that block this interaction could potentially inhibit SARS-CoV-2 infection into the host cells. To identify such drugs, we first analyzed the recently published crystal structure of S-protein-hACE2 complex and identified essential residues of both S-protein and hACE2 for this interaction. We used this knowledge to virtually dock a drug library containing 4115 drug molecules against S-protein for repurposing drugs that could inhibit binding of S-protein to hACE2. We identified several potential inhibitors based on their docking scores, pharmacological effects and ability to block residues of S protein required for interaction with hACE2. The top inhibitors included drugs used for the treatment of hepatitis C (velpatasvir, pibrentasvir) as well as several vitamin D derivatives. Several molecules obtained from our screen already have good experimental support in published literature. Thus, we believe that our results will facilitate the discovery of an effective drug against COVID-19. Communicated by Ramaswamy H. Sarma.

Hepatobiliary involvement in COVID-19 patients

As the new data emerges from the studies regarding COVID-19 infection, various complications are detected among the infected patients. Unlike its name, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is not limited to the respiratory system1. Some studies have suggested the impact of COVID-19 on liver function2,3. Since the liver plays essential intoxication, enzyme activation, storage, and synthesis of necessary proteins, lipids, and carbohydrates, the potential liver complications may affect the body beyond ordinary expectations.

Multi-conformation representation of Mpro identifies promising candidates for drug repurposing against COVID-19

The COVID-19 main protease (Mpro), one of the conserved proteins of the novel coronavirus is crucial for its replication and so is a very lucrative drug target. Till now, there is no drug molecule that has been convincingly identified as the inhibitor of the function of this protein. The current pandemic situation demands a shortcut to quickly reach to a lead compound or a drug, which may not be the best but might serve as an interim solution at least. Following this notion, the present investigation uses virtual screening to find a molecule which is alraedy approved as a drug for some other disease but could be repurposed to inhibit Mpro. The potential of the present method of work to identify such a molecule, which otherwise would have been missed out, lies in the fact that instead of just using the crystallographically identified conformation of the receptor’s ligand binding pocket, molecular dynamics generated ensemble of conformations has been used. It implicitly included the possibilities of “induced-fit” and/or “population shift” mechanisms of ligand fitting. As a result, the investigation has not only identified antiviral drugs like ribavirin, ritonavir, etc., but it has also captured a wide variety of drugs for various other diseases like amrubicin, cangrelor, desmopressin, diosmin, etc. as the potent possibilities. Some of these ligands are versatile to form stable interactions with various different conformations of the receptor and therefore have been statistically surfaced in the investigation. Overall the investigation offers a wide range of compounds for further testing to confirm their scopes of applications to combat the COVID-19 pandemic.

Rutin: A Potential Antiviral for Repurposing as a SARS-CoV-2 Main Protease (Mpro) Inhibitor

Various computational studies, including in silico ones, have identified several existing compounds that could serve as effective inhibitors of the SARS-CoV-2 main protease (Mpro), and thus preventing replication of the virus. Among these, rutin has been identified as a potential hit, having prominent binding affinity to the virus. Moreover, its presence in several traditional antiviral medicines prescribed in China to infected patients with mild to moderate symptoms of COVID-19 justify its promise as a repurposed bioactive secondary metabolite against SARS-CoV-2.

COVID-19 Treatment Guidelines: Do They Really Reflect Best Medical Practices to Manage the Pandemic?

SARS-CoV-2 (COVID-19) has been changing the world since December 2019. A comprehensive search into many COVID-19 treatment guidelines was conducted and reported in this article. This is a review paper to probe differences in COVID-19 managing strategies and explore the most common treatment plans among countries. Published guidelines from 23 countries and three references guidelines-until the end of 2020-were included in this article. The majority of COVID-19 treatment options were reported in this review and it includes antiviral drugs, antimalarial drugs, antibiotics, corticosteroids, immunotherapy, anticoagulants, and other pharmacological treatment. The presence of such information from different countries in a single comprehensive review article could help in understanding and speculation of variation in the recommended treatment in each country. This might be related to the cost of medications, the access to the medications, availability of medication that could potentially be useful in managing COVID-19 cases, and the availability/capacity of healthcare facilities. Finally, although there are various treatment groups listed in the published therapeutic guidelines worldwide, unfortunately, there is no evidence for effectiveness of most of these medications in reducing the COVID-19 mortality curve over more than one year of this global pandemic.

Dose prediction for repurposing nitazoxanide in SARS-CoV-2 treatment or chemoprophylaxis

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been declared a global pandemic and urgent treatment and prevention strategies are needed. Nitazoxanide, an anthelmintic drug, has been shown to exhibit in vitro activity against SARS-CoV-2. The present study used physiologically based pharmacokinetic (PBPK) modelling to inform optimal doses of nitazoxanide capable of maintaining plasma and lung tizoxanide exposures above the reported SARS-CoV-2 EC90 .

METHODS

A whole-body PBPK model was validated against available pharmacokinetic data for healthy individuals receiving single and multiple doses between 500 and 4000 mg with and without food. The validated model was used to predict doses expected to maintain tizoxanide plasma and lung concentrations above the EC90 in >90% of the simulated population. PopDes was used to estimate an optimal sparse sampling strategy for future clinical trials.

RESULTS

The PBPK model was successfully validated against the reported human pharmacokinetics. The model predicted optimal doses of 1200 mg QID, 1600 mg TID and 2900 mg BID in the fasted state and 700 mg QID, 900 mg TID and 1400 mg BID when given with food. For BID regimens an optimal sparse sampling strategy of 0.25, 1, 3 and 12 hours post dose was estimated.

CONCLUSION

The PBPK model predicted tizoxanide concentrations within doses of nitazoxanide already given to humans previously. The reported dosing strategies provide a rational basis for design of clinical trials with nitazoxanide for the treatment or prevention of SARS-CoV-2 infection. A concordant higher dose of nitazoxanide is now planned for investigation in the seamless phase I/IIa AGILE trial.

Structure- and Ligand-Based in silico Studies towards the Repurposing of Marine Bioactive Compounds to Target SARS-CoV-2

This work was a structured virtual screening for marine bioactive compounds with reported antiviral activities which were subjected to structure-based studies against SARS-CoV-2 co-crystallized proteins. The molecular docking of marine bioactive compounds against the main protease (Mpro, PDB ID: 6lu7 and 6y2f), the spike glycoprotein (PDB ID: 6vsb), and the RNA polymerase (PDB ID: 6m71) of SARS-CoV-2 was performed. Ligand-based approach with the inclusion of rapid overlay chemical structures (ROCS) was also addressed in order to examine the probability of these marine compounds sharing relevance and druggability with the reported drugs. Among the examined marine library, the highest scores in different virtual screening aspects were displayed by compounds with flavonoids core, acyl indole, and pyrrole carboxamide alkaloids. Moreover, a complete overlay with the co-crystallized ligands of Mpro was revealed by sceptrin and debromo-sceptrin. Thalassoilin (A-B) which was found in the Red Sea exhibited the highest binding and similarity outcomes among all target proteins. These data highlight the importance of marine natural metabolites in regard to further studies for discovering new drugs to combat the COVID-19 pandemic.

P, Biatris PS, J. SJUC. Therapeutic role of corticosteroids in COVID-19: a systematic review of registered clinical trials

BACKGROUND

In March 2020, the World Health Organization declared the coronavirus disease 2019 as a global pandemic. Though antiviral drugs and antimalarial drugs are considered treatment options for treating coronavirus disease 2019 (COVID-19), no specific antivirals are currently available for its treatment. Efficient use of drug discovery approaches including repurposing or repositioning of drugs used in the treatment of severe acute respiratory syndrome coronavirus (SARS-CoV) and the Middle East respiratory syndrome coronavirus (MERS-CoV) is considered recently. The widespread application of corticosteroid therapy in COVID-19 should be backed with careful documented pragmatic research of its use in this context.

MAIN BODY

This article aims to analyze various trials registered across the globe providing an overall picture of the use of corticosteroids in the treatment of COVID-19. An extensive search was conducted on the clinical trial registries around the world to identify all the trials reporting information regarding the use of corticosteroids in COVID-19. Our initial search returned 231 trials, out of which 60 trials were finally included in the analysis. Fifty-six studies were interventional trials, and all the trials had clearly defined primary and secondary outcomes of interest, of which only 11 trials had evaluation of respiratory rate as one of their outcomes.

CONCLUSION

Few preliminary trial findings show promising results and recommend the use of methylprednisolone and dexamethasone in the severe form of the disease; however, there is insufficient data to prove its benefits over its risks. Routine use of corticosteroids should be favored only after a better insight is obtained, with the completion of these trials.

Artificial Intelligence-Aided Precision Medicine for COVID-19: Strategic Areas of Research and Development

Artificial intelligence (AI) technologies can play a key role in preventing, detecting, and monitoring epidemics. In this paper, we provide an overview of the recently published literature on the COVID-19 pandemic in four strategic areas: (1) triage, diagnosis, and risk prediction; (2) drug repurposing and development; (3) pharmacogenomics and vaccines; and (4) mining of the medical literature. We highlight how AI-powered health care can enable public health systems to efficiently handle future outbreaks and improve patient outcomes.

Concomitant use of dexamethasone and tetracyclines: a potential therapeutic option for the management of severe COVID-19 infection?

Introduction: The global coronavirus disease-2019 (COVID-19) pandemic has posed a critical challenge to the research community as well as to the healthcare systems. Severe COVID-19 patients are at a higher risk of developing serious complications and mortality. There is a dire need for safe and effective pharmacotherapy for addressing unmet needs of these patients. Concomitant use of dexamethasone and tetracyclines, by virtue of their immunomodulatory and other relevant pharmacological properties, offers a potential strategy for synergy aimed at improving clinical outcomes.Areas covered: Here we review the potential benefits of combining dexamethasone and tetracyclines (minocycline or doxycycline) for the management of severe COVID-19 patients. We have critically examined the evidence obtained from in silico, experimental, and clinical research. We have also discussed the plausible mechanisms, advantages, and drawbacks of this proposed combination therapy for managing severe COVID-19.Expert opinion: The concomitant use of dexamethasone and one of the tetracyclines among severe COVID-19 patients offers several advantages in terms of additive immunomodulatory effects, cost-effectiveness, wide-availability, and well-known pharmacological properties including adverse-effect profile and contraindications. There is an urgent need to facilitate pilot studies followed by well-designed and adequately-powered multicentric clinical trials to generate conclusive evidence related to utility of this approach.

Drug Repurposing and Polypharmacology to Fight SARS-CoV-2 Through Inhibition of the Main Protease

The outbreak of a new coronavirus (SARS-CoV-2), which is responsible for the COVID-19 disease and is spreading rapidly around the world, urgently requires effective therapeutic treatments. In this context, drug repurposing represents a valuable strategy, as it enables accelerating the identification of drug candidates with already known safety profiles, possibly aiding in the late stages of clinical evaluation. Moreover, therapeutic treatments based on drugs with beneficial multi-target activities (polypharmacology) may show an increased antiviral activity or help to counteract severe complications concurrently affecting COVID-19 patients. In this study, we present the results of a computational drug repurposing campaign that aimed at identifying potential inhibitors of the main protease (Mpro) of the SARS-CoV-2. The performed in silico screening allowed the identification of 22 candidates with putative SARS-CoV-2 Mpro inhibitory activity. Interestingly, some of the identified compounds have recently entered clinical trials for COVID-19 treatment, albeit not being assayed for their SARS-CoV-2 antiviral activity. Some candidates present a polypharmacology profile that may be beneficial for COVID-19 treatment and, to the best of our knowledge, have never been considered in clinical trials. For each repurposed compound, its therapeutic relevance and potential beneficial polypharmacological effects that may arise due to its original therapeutic indication are thoroughly discussed.

Molecular docking, binding mode analysis, molecular dynamics, and prediction of ADMET/toxicity properties of selective potential antiviral agents against SARS-CoV-2 main protease: an effort toward drug repurposing to combat COVID-19

The importance of the main protease (M^pro) enzyme of SARS-CoV-2 in the digestion of viral polyproteins introduces M^pro as an attractive drug target for antiviral drug design. This study aims to carry out the molecular docking, molecular dynamics studies, and prediction of ADMET properties of selected potential antiviral molecules. The study provides an insight into biomolecular interactions to understand the inhibitory mechanism and the spatial orientation of the tested ligands and further, identification of key amino acid residues within the substrate-binding pocket that can be applied for structure-based drug design. In this regard, we carried out molecular docking studies of chloroquine (CQ), hydroxychloroquine (HCQ), remdesivir (RDV), GS441524, arbidol (ARB), and natural product glycyrrhizin (GA) using AutoDock 4.2 tool. To study the drug-receptor complex's stability, selected docking possesses were further subjected to molecular dynamics studies with Schrodinger software. The prediction of ADMET/toxicity properties was carried out on ADMET Prediction™. The docking studies suggested a potential role played by CYS145, HIS163, and GLU166 in the interaction of molecules within the active site of COVID-19 M^pro. In the docking studies, RDV and GA exhibited superiority in binding with the crystal structure of M^pro over the other selected molecules in this study. Spatial orientations of the molecules at the active site of M^pro exposed the significance of S1–S4 subsites and surrounding amino acid residues. Among GA and RDV, RDV showed better and stable interactions with the protein, which is the reason for the lesser RMSD values for RDV. Overall, the present in silico study indicated the direction to combat COVID-19 using FDA-approved drugs as promising agents, which do not need much toxicity studies and could also serve as starting points for lead optimization in drug discovery.

Neopterin: A Promising Candidate Biomarker for Severe COVID-19

Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection has rapidly spread across the world since its first emergence in China in late 2019. It is a major public health concern with no effective treatct 3ments. The immunopathology of SARS-CoV-2 is associated with an excessive inflammatory response. Macrophage activation syndrome (MAS) is also associated with the severity of the disease in SARS-CoV-2-infected patients. Neopterin is a macrophage activation marker produced by monocytes and macrophages upon activation by interferon-gamma (IFN-γ). Neopterin is a well-established marker in a variety of diseases, and recent evidence indicates that it could be helpful in early prediction of the severity of COVID-19 disease and serve as a prognostic marker. Here, we outline the role of macrophage activation syndrome in the pathogenesis of SARS-CoV-2 and suggest that neopterin could be used as a biomarker for progression of COVID-19.

Screened antipsychotic drugs inhibit SARS-CoV-2 binding with ACE2 in vitro

AIM

The coronavirus disease 2019 (COVID-19) pandemic has swept the globe and no specific effective drug has been identified. Drug repurposing is a well-known method to address the crisis in a time-critical fashion. Antipsychotic drugs (APDs) have been reported to inhibit DNA replication of hepatitis B virus, measles virus germination, and HIV infection, along with replication of SARS-CoV and MERS-CoV, both of which interact with host cells as SARS-CoV-2.

METHODS

Nineteen APDs were screened using ACE2-HEK293T cell membrane chromatography (ACE2-HEK293T/CMC). Cytotoxicity assay, coronavirus spike pseudotype virus entry assay, surface plasmon resonance, and virtual molecular docking were applied to detect affinity between ACE2 protein and drugs and a potential antiviral property of the screened compounds.

KEY FINDINGS

After the CMC screening, 8 of the 19 APDs were well-retained on ACE2-HEK293T/CMC column and showed significant antiviral activities in vitro. Three quarters of them belong to phenothiazine and could significantly inhibit the entrance of coronavirus into ACE2-HEK293T cells. Aother two drugs, aripiprazole and tiapride, exhibited weaker inhibition. We selected five of the drugs for subsequent evaluation. All five showed similar affinity to ACE2 and virtual molecular docking demonstrated they bound with different amino acids respectively on ACE2 which SARS-CoV-2 binds to.

SIGNIFICANCE

Eight APDs were screened for binding with ACE2, five of which demonstrated potential protective effects against SARS-CoV-2 through acting on ACE2. Although the five drugs have a weak ability to block SARS-CoV-2 with a single binding site, they may provide a synergistic effect in adjuvant therapy of COVID-19 infection.

Control and prevention of infectious diseases from a One Health perspective

The ongoing COVID-19 pandemic has caught the attention of the global community and rekindled the debate about our ability to prevent and manage outbreaks, epidemics, and pandemics. Many alternatives are suggested to address these urgent issues. Some of them are quite interesting, but with little practical application in the short or medium term. To realistically control infectious diseases, human, animal, and environmental factors need to be considered together, based on the One Health perspective. In this article, we highlight the most effective initiatives for the control and prevention of infectious diseases: vaccination; environmental sanitation; vector control; social programs that encourage a reduction in the population growth; control of urbanization; safe sex stimulation; testing; treatment of sexually and vertically transmitted infections; promotion of personal hygiene practices; food safety and proper nutrition; reduction of the human contact with wildlife and livestock; reduction of social inequalities; infectious disease surveillance; and biodiversity preservation. Subsequently, this article highlights the impacts of human genetics on susceptibility to infections and disease progression, using the SARS-CoV-2 infection as a study model. Finally, actions focused on mitigation of outbreaks and epidemics and the importance of conservation of ecosystems and translational ecology as public health strategies are also discussed.

SARS-CoV-2 protein drug targets landscape: a potential pharmacological insight view for the new drug development

Introduction: Protein drug targets play a significant choice in different stages of the drug discovery process. There is an urgent need to understand the drug discovery approaches and protein drug targets (PDT) of SARS-CoV-2, with structural insights for the development of SARS-CoV-2 drugs through targeted therapeutic approach.Areas covered: We have described the protein as a drug target class and also discussed various drug discovery approaches for SARS-CoV-2 involving the protein drug targets such as drug repurposing study, designing of viral entry inhibitors, viral replication inhibitors, and different enzymes of the virus. We have performed comprehensive literature search from the popular databases such as PubMed Google scholar, Web of Science, and Scopus. Finally, we have illustrated the structural landscape of different significant viral proteins (3 CLpro or Mpro, PLpro, RdRp, helicase, S protein) and host proteins as drug targets (cathepsin L, furin, TMPRSS2, ACE2).Expert opinion: The structural landscape of PDT with their binding pockets, and significant residues involved in binding has been discussed further to better understand the PDT and the structure-based drug discovery for SARS-CoV-2. This attempt will increase more therapeutic options, and combination therapies with a multi-target strategy.

Computational drug repurposing strategy predicted peptide-based drugs that can potentially inhibit the interaction of SARS-CoV-2 spike protein with its target (humanACE2)

Drug repurposing for COVID-19 has several potential benefits including shorter development time, reduced costs and regulatory support for faster time to market for treatment that can alleviate the current pandemic. The current study used molecular docking, molecular dynamics and protein-protein interaction simulations to predict drugs from the Drug Bank that can bind to the SARS-CoV-2 spike protein interacting surface on the human angiotensin-converting enzyme 2 (hACE2) receptor. The study predicted a number of peptide-based drugs, including Sar9 Met (O2)11-Substance P and BV2, that might bind sufficiently to the hACE2 receptor to modulate the protein-protein interaction required for infection by the SARS-CoV-2 virus. Such drugs could be validated in vitro or in vivo as potential inhibitors of the interaction of SARS-CoV-2 spike protein with the human angiotensin-converting enzyme 2 (hACE2) in the airway. Exploration of the proposed and current pharmacological indications of the peptide drugs predicted as potential inhibitors of the interaction between the spike protein and hACE2 receptor revealed that some of the predicted peptide drugs have been investigated for the treatment of acute respiratory distress syndrome (ARDS), viral infection, inflammation and angioedema, and to stimulate the immune system, and potentiate antiviral agents against influenza virus. Furthermore, these predicted drug hits may be used as a basis to design new peptide or peptidomimetic drugs with better affinity and specificity for the hACE2 receptor that may prevent interaction between SARS-CoV-2 spike protein and hACE2 that is prerequisite to the infection by the SARS-CoV-2 virus.

Primed for global coronavirus pandemic: Emerging research and clinical outcome

The global effort to combat and contain the coronavirus disease 2019 (COVID-19) caused by the recently discovered severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is now proceeding on a war footing. The world was slow to react to the developing crisis, but once the contours of the impending calamity became evident, the different state and non-state actors have raced to put their act together. The COVID-19 pandemic has blatantly exposed the shortcomings of our healthcare system and the limitations of medical science, despite considerable advances in recent years. To effectively tackle the current pandemic, almost unprecedented in the modern age, there is an urgent need for a concerted, sustained, and coordinated effort towards the development of new diagnostics, therapeutic and vaccines, and the ramping up of the healthcare infrastructure, especially in the poorer underprivileged nations. Towards this end, researchers around the world are working tirelessly to develop new diagnostics, vaccines, and therapeutics. Efforts to develop a vaccine against COVID-19 are presently underway in several countries around the world, but a new vaccine is expected only by the end of the year-at the earliest. New drug development against COVID-19 and its approval may take even longer. Under such circumstances, drug repurposing has emerged as a realistic and effective strategy to counter the current menace, and several antiviral and antimalarial medicines are currently in different stages of clinical trials. Researchers are also experimenting with nutrients, vitamins, monoclonal antibodies, and convalescent plasma as immunity boosters against the SARS-CoV-2. This report presents a critical analysis of the global clinical trial landscape for COVID-19 with an emphasis on the therapeutic agents and vaccines currently being tested at pandemic speed.

Emerging from the other end: Key measures for a successful COVID-19 lockdown exit strategy and the potential contribution of pharmacists

As the world edges towards relaxing the lockdown measures taken to control the spread of the novel coronavirus SARS-CoV-2 (COVID-19), governments have started putting in place a variety of measures to avoid a second peak in the number of infections. The implementation of and adherence to such measures will be key components of any successful lockdown exit strategy. Ranging from expanded testing and widespread use of technology to building the public's trust in the post COVID-19 world, there is a role for pharmacists to play. In this commentary, these measures and the potential contribution of pharmacists to their successful implementation are outlined and discussed.

Inovação, propriedade intelectual e acesso a medicamentos e vacinas: o debate internacional na pandemia da Covid-19

Este estudo analisa o debate internacional sobre vários aspectos do acesso a produtos de saúde, notadamente medicamentos e vacinas, no âmbito da Covid-19: estratégias de inovação (por exemplo, reposicionamento de fármacos), a discussão pública de alto nível sobre vacinas como bens públicos globais, os direitos de propriedade intelectual e as flexibilidades do Acordo TRIPS, os acordos para transferência de tecnologia e as questões de comércio. A pandemia concentrou imensos esforços tecnológicos, que, no futuro, podem estimular a revitalização das políticas públicas de ciência, a inovação e produção, as competências estatais, as parcerias público-privadas, e a alocação estratégica de investimentos contribuindo para os processos de catching-up tecnológico

Nanotheranostics against COVID-19: From multivalent to immune-targeted materials

Destructive impacts of COVID-19 pandemic worldwide necessitates taking more appropriate measures for mitigating virus spread and development of the effective theranostic agents. In general, high heterogeneity of viruses is a major challenging issue towards the development of effective antiviral agents. Regarding the coronavirus, its high mutation rates can negatively affect virus detection process or the efficiency of drugs and vaccines in development or induce drug resistance. Bioengineered nanomaterials with suitable physicochemical characteristics for site-specific therapeutic delivery, highly-sensitive nanobiosensors for detection of very low virus concentration, and real-time protections using the nanorobots can provide roadmaps towards the imminent breakthroughs in theranostics of a variety of diseases including the COVID-19. Besides revolutionizing the classical disinfection procedures, state-of-the-art nanotechnology-based approaches enable providing the analytical tools for accelerated monitoring of coronavirus and associated biomarkers or drug delivery towards the pulmonary system or other affected organs. Multivalent nanomaterials capable of interaction with multivalent pathogens including the viruses could be suitable candidates for viral detection and prevention of further infections. Besides the inactivation or destruction of the virus, functionalized nanoparticles capable of modulating patient's immune response might be of great significance for attenuating the exaggerated inflammatory reactions or development of the effective nanovaccines and medications against the virus pandemics including the COVID-19.