Efficacy of Remdesivir in COVID-19

Nonpeptidic Irreversible Inhibitors of SARS-CoV-2 Main Protease with Potent Antiviral Activity

SARS-CoV-2 infections pose a high risk for vulnerable patients. In this study, we designed benzoic acid halopyridyl esters bearing a variety of substituents as irreversible inhibitors of the main viral protease (Mpro). Altogether, 55 benzoyl chloro/bromo-pyridyl esters were synthesized, with broad variation of the substitution pattern on the benzoyl moiety. A workflow was employed for multiparametric optimization, including Mpro inhibition assays of SARS-CoV-2 and related pathogenic coronaviruses, the duration of enzyme inhibition, the compounds' stability versus glutathione, cytotoxicity, and antiviral activity. Several compounds showed IC50 values in the low nanomolar range, kinact/Ki values of >100,000 M-1 s-1 and high antiviral activity. High-resolution X-ray cocrystal structures indicated an important role of ortho-fluorobenzoyl substitution, forming a water network that stabilizes the inhibitor-bound enzyme. The most potent antiviral compound was the p-ethoxy-o-fluorobenzoyl chloropyridyl ester (PSB-21110, 29b, MW 296 g/mol; EC50 2.68 nM), which may serve as a lead structure for broad-spectrum anticoronaviral therapeutics.

Unveiling the Antiviral Capabilities of Targeting Human Dihydroorotate Dehydrogenase against SARS-CoV-2

The urgent need for effective treatments against emerging viral diseases, driven by drug-resistant strains and new viral variants, remains critical. We focus on inhibiting the human dihydroorotate dehydrogenase (HsDHODH), one of the main enzymes responsible for pyrimidine nucleotide synthesis. This strategy could impede viral replication without provoking resistance. We evaluated naphthoquinone fragments, discovering potent HsDHODH inhibition with IC50 ranging from 48 to 684 nM, and promising in vitro anti-SARS-CoV-2 activity with EC50 ranging from 1.2 to 2.3 μM. These compounds exhibited low toxicity, indicating potential for further development. Additionally, we employed computational tools such as molecular docking and quantitative structure-activity relationship (QSAR) models to analyze protein-ligand interactions, revealing that these naphthoquinones exhibit a protein binding pattern similar to brequinar, a potent HsDHODH inhibitor. These findings represent a significant step forward in the search for effective antiviral treatments and have great potential to impact the development of new broad-spectrum antiviral drugs.

Cathepsin-Targeting SARS-CoV-2 Inhibitors: Design, Synthesis, and Biological Activity

Cathepsins (Cats) are proteases that mediate the successful entry of SARS-CoV-2 into host cells. We designed and synthesized a tailored series of 21 peptidomimetics and evaluated their inhibitory activity against human cathepsins L, B, and S. Structural diversity was realized by combinations of different C-terminal warhead functions and N-terminal capping groups, while a central Leu-Phe fragment was maintained. Several compounds were identified as promising cathepsin L and S inhibitors with Ki values in the low nanomolar to subnanomolar range, for example, the peptide aldehydes 9a and 9b (9a, 2.67 nM, CatL; 0.455 nM, CatS; 9b, 1.76 nM, CatL; 0.512 nM, CatS). The compounds' inhibitory activity against the main protease of SARS-CoV-2 (Mpro) was additionally investigated. Based on the results at CatL, CatS, and Mpro, selected inhibitors were subjected to investigations of their antiviral activity in cell-based assays. In particular, the peptide nitrile 11e exhibited promising antiviral activity with an EC50 value of 38.4 nM in Calu-3 cells without showing cytotoxicity. High metabolic stability and favorable pharmacokinetic properties make 11e suitable for further preclinical development.

Novel ProTide prodrugs of 5-fluoro-2'-deoxyuridine for the treatment of liver cancer

ProTide prodrug technology has emerged as a promising way for the development of anti-viral and anti-tumor drugs, whereas, there are fewer applications for the treatment of liver cancer. Herein, a series of distinct 3'-ester ProTide prodrugs of 5-fluoro-2'-deoxyuridine (FdUR) were synthesized and evaluated for their anti-liver cancer activity. The most efficient prodrug 11b reached a sub-micromolar activity (IC50 = 0.42 ± 0.13 μM) against HepG2 and over 100-fold and 200-fold improvements compared to 5-FU, respectively. 11b also demonstrated favorable selectivity towards normal liver cells L-02 (IC50 > 100 μM). In vitro metabolic stability studies revealed that 11b is stable in the plasma and could be activated rapidly in the liver, which supported that 11b is liver-targeted. Importantly, to more accurately evaluate the anti-HCC activity of 11b, the liver orthotopic model was built and 11b significantly suppressed tumor growth (TGI = 75.5%) at a dose of 60 mg/kg/2d in vivo without obvious toxicity. Overall, these promising results indicated that 11b could serve as a safe and effective prodrug of 5-FU nucleoside for liver cancer therapy.

Multi-omics for COVID-19: driving development of therapeutics and vaccines

The ongoing COVID-19 pandemic caused by SARS-CoV-2 has raised global concern for public health and economy. The development of therapeutics and vaccines to combat this virus is continuously progressing. Multi-omics approaches, including genomics, transcriptomics, proteomics, metabolomics, epigenomics and metallomics, have helped understand the structural and molecular features of the virus, thereby assisting in the design of potential therapeutics and accelerating vaccine development for COVID-19. Here, we provide an up-to-date overview of the latest applications of multi-omics technologies in strategies addressing COVID-19, in order to provide suggestions towards the development of highly effective knowledge-based therapeutics and vaccines.

Adjusted green spectrophotometric determination of favipiravir and remdesivir in pharmaceutical form and spiked human plasma sample using different chemometric supported models

The environmentally friendly design of analytical methods is gaining interest in pharmaceutical analysis to reduce hazardous environmental impacts and improve safety and health conditions for analysts. The adaptation and integration of chemometrics in the development of environmentally friendly analytical methods is strongly recommended in the hope of promising benefits. Favipiravir and remdesivir have been included in the COVID-19 treatment guidelines panel of several countries. The main objective of this work is to develop green, tuned spectrophotometric methods based on chemometric based models for the determination of favipiravir and remdesivir in spiked human plasma. The UV absorption spectra of favipiravir and remdesivir has shown overlap to some extent, making simultaneous determination difficult. Three advanced chemometric models, classical least squares, principal component regression, and partial least squares, have been developed to provide resolution and spectrophotometric determination of the drugs under study. A five-level, two-factor experimental design has been used to create the described models. The spectrally recorded data of favipiravir and remdesivir has been reviewed. The noise region has been neglected as it has a negative impact on the significant data. On the other hand, the other spectral data provided relevant information about the investigated drugs. A comprehensive evaluation and interpretation of the results of the described models and a statistical comparison with accepted values have been considered. The proposed models have been successfully applied to the spectrophotometric determination of favipiravir and remdesivir in pharmaceutical form spiked human plasma. In addition, the environmental friendliness of the described models was evaluated using the analytical eco-scale, the green analytical procedure index and the AGREE evaluation method. The results showed the compliance of the described models with the environmental characteristics.

Inspiratory Muscle Training While Hospitalized With Acute COVID-19 Respiratory Failure: A Randomized Controlled Trial

Although inspiratory muscle training (IMT) has been used in outpatient settings for patients who recovered from COVID-19 respiratory failure, little data exist to support earlier implementation in acute care hospitals. This study aimed to assess the safety and feasibility of IMT during the acute disease phase of COVID-19.

Design Setting and Patients

Sixty patients presenting with COVID-19 to a single academic medical center were randomized to control or intervention groups using systematic randomization.

Measurements

Participants in the control group had their maximal inspiratory pressure (MIP) measured at enrollment and hospital discharge. They were also asked for their rating of perceived exertion on the Revised Borg Scale for Grading Severity of Dyspnea and were scored by researchers on the Activity Measure for Post-Acute Care (AM-PAC) 6-Clicks Mobility Scale and the Intensive Care Unit Mobility Scale (IMS). Control group patients otherwise received standard care. Participants in the intervention group, in addition to the measures described previously, received inspiratory threshold trainers with the goal of doing 2 sessions daily with a physical therapist for the duration of their inpatient hospitalization. In these sessions, the patient completed 3 sets of 10 breaths with the trainer. Initial resistance was set at 30% of their MIP, with resistance increasing 1 level for the subsequent session if the patients rated their during-activity rating of perceived exertion as less than 2. Changes in functional outcome measures, amount of supplemental oxygen, hospital length of stay (LOS), discharge location, adverse events, and mortality were assessed in group comparisons.

Results

Of 60 enrolled patients, 41 (n = 19 in intervention and n = 22 in control) were included in the final data set, which required completion of the study, initial and discharge data points collected, and survival of hospitalization. Final groups were statistically similar. A total of 161 sessions of IMT were completed among the 19 patients in the intervention group. Mortality totaled 2 in the control group and 3 in the intervention group and adverse events during intervention occurred in only 3 (1.8%) sessions, all of which were minor oxygen desaturations. Sessions were unable to be completed for all potential reasons 11% of possible times. Dropout rate in the intervention group was 3 (10%). Both intervention and control groups demonstrated improved MIP, decreased supplemental oxygen requirements, improved function on the AM-PAC, and slightly decreased function on the IMS. Length of stay was shorter in the intervention group, and discharge disposition was similar between groups.

Conclusions

With a low number of recorded adverse events, similar mortality between groups, and successful completion of 161 exercise sessions, IMT may be a feasible and safe intervention for some hospitalized patients with COVID-19.

Combined effect of early diagnosis and treatment on the case fatality risk of COVID-19 in Japan, 2020

Japanese government initially enforced restrictions on outpatient attendances among febrile individuals suspected of having COVID-19, asking everyone to remain at home for at least 4 days from the onset of fever. This restriction was cancelled on 8 May 2020, and a new antiviral, remdesivir, was approved from 7 May 2020. To investigate how this policy change influenced the prognosis of people with COVID-19, we estimated the case fatality risk as a function of the date of illness onset from April to June 2020. We used an interrupted time-series analysis model with an intervention date of 8 May 2020, and estimated time-dependent case fatality risk by age group. The case fatality risk showed a decreasing trend in all groups, and models were favored accounting for an abrupt causal effect, i.e., immediate decline in fatality risk. The trend was estimated at - 1.1% (95% CI [confidence interval]: - 3.9, 3.0) among people aged 60-69 years, - 7.2% (95% CI - 11.2, - 2.4) among those aged 70-79 years, - 7.4% (95% CI - 14.2, 0.2) among those aged 80-89 years, and - 10.3% (95% CI - 21.1, 2.7) among those aged 90 and over. Early diagnosis and treatment greatly contributed to reducing the case fatality risk.

Treating SARS-CoV-2 Omicron variant infection by molnupiravir for pandemic mitigation and living with the virus: a mathematical modeling study

Treating severe COVID-19 patients and controlling the spread of SARS-CoV-2 are concurrently important in mitigating the pandemic. Classically, antiviral drugs are primarily developed for treating hospitalized COVID-19 patients with severe diseases to reduce morbidity and/or mortality, which have limited effects on limiting pandemic spread. In this study, we simulated the expanded applications of oral antiviral drugs such as molnupiravir to mitigate the pandemic by treating nonhospitalized COVID-19 cases. We developed a compartmental mathematical model to simulate the effects of molnupiravir treatment assuming various scenarios in the Omicron variant dominated settings in Denmark, the United Kingdom and Germany. We found that treating nonhospitalized cases can limit Omicron spread. This indirectly reduces the burden of hospitalization and patient death. The effectiveness of this approach depends on the intrinsic nature of the antiviral drug and the strategies of implementation. Hypothetically, if resuming pre-pandemic social contact pattern, extensive application of molnupiravir treatment would dramatically (but not completely) mitigate the COVID-19 burden, and thus there remains lifetime cost of living with the virus.

Design and synthesis of naturally-inspired SARS-CoV-2 inhibitors

A naturally inspired chemical library of 25 molecules was synthesised guided by 3-D dimensionality and natural product likeness factors to explore a new chemical space. The synthesised chemical library, consisting of fused-bridged dodecahydro-2a,6-epoxyazepino[3,4,5-c,d]indole skeletons, followed lead likeness factors in terms of molecular weight, C-sp3 fraction and Clog P. Screening of the 25 compounds against lung cells infected with SARS-CoV-2 led to the identification of 2 hits. Although the chemical library showed cytotoxicity, the two hits (3b, 9e) showed the highest antiviral activity (EC50 values of 3.7 and 1.4 μM, respectively) with an acceptable cytotoxicity difference. Computational analysis based on docking and molecular dynamics simulations against main protein targets in SARS-CoV-2 (main protease Mpro, nucleocapsid phosphoprotein, non-structural protein nsp10-nsp16 complex and RBD/ACE2 complex) were performed. The computational analysis proposed the possible binding targets to be either Mpro or the nsp10-nsp16 complex. Biological assays were performed to confirm this proposition. A cell-based assay for Mpro protease activity using a reverse-nanoluciferase (Rev-Nluc) reporter confirmed that 3b targets Mpro. These results open the way towards further hit-to-lead optimisations.

Therapeutic Strategies in the Fight against COVID-19: From Bench to Bedside

In December 2019, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in China. This virus rapidly spread worldwide and was declared a global pandemic by the World Health Organization (WHO) in March 2020. High incidence, long incubation period, and diverse clinical signs of the disease posed a huge challenge globally. The efforts of health systems have been focused on repurposing existing drugs or developing innovative therapies to reduce the morbidity and mortality associated with SARS-CoV-2. In addition, most of the large pharmaceutical companies are intensely working on vaccine development to swiftly deliver safe and effective vaccines to prevent further spread of the virus. In this review, we will discuss the latest data on therapeutic strategies undergoing clinical trials. Additionally, we will provide a summary of vaccines currently under development.

Advanced Molecular Tweezers with Lipid Anchors against SARS-CoV-2 and Other Respiratory Viruses

The COVID-19 pandemic caused by SARS-CoV-2 presents a global health emergency. Therapeutic options against SARS-CoV-2 are still very limited but urgently required. Molecular tweezers are supramolecular agents that destabilize the envelope of viruses resulting in a loss of viral infectivity. Here, we show that first-generation tweezers, CLR01 and CLR05, disrupt the SARS-CoV-2 envelope and abrogate viral infectivity. To increase the antiviral activity, a series of 34 advanced molecular tweezers were synthesized by insertion of aliphatic or aromatic ester groups on the phosphate moieties of the parent molecule CLR01. A structure-activity relationship study enabled the identification of tweezers with a markedly enhanced ability to destroy lipid bilayers and to suppress SARS-CoV-2 infection. Selected tweezer derivatives retain activity in airway mucus and inactivate the SARS-CoV-2 wildtype and variants of concern as well as respiratory syncytial, influenza, and measles viruses. Moreover, inhibitory activity of advanced tweezers against respiratory syncytial virus and SARS-CoV-2 was confirmed in mice. Thus, potentiated tweezers are broad-spectrum antiviral agents with great prospects for clinical development to combat highly pathogenic viruses.

Successful immunomodulation in kidney transplant recipients with cytokine release syndrome after coronavirus disease

Introduction

Patients with coronavirus disease, especially solid organ transplant recipients, are more susceptible to developing cytokine release syndrome than those with other viral infections. However, currently, treatment methods for such patients have not been established. Here, we describe two cases of successful immunomodulation in Japanese kidney transplant recipients with cytokine release syndrome following coronavirus disease.

Case presentation

Two patients who had been receiving long‐term immunosuppressant therapy developed coronavirus disease‐associated pneumonia caused by cytokine release syndrome, following immunosuppressant dosage reduction. However, they recovered immediately after administration of tocilizumab with or without dexamethasone.

Conclusion

The immunosuppressant dosage should be reduced to restore host immunity; however, immunomodulation should be considered in cases of suspected cytokine release syndrome.

Spectrophotometric quantitative analysis of remdesivir using acid dye reagent selected by computational calculations

Remdesivir was approved by the Food and Drug Administration for the treatment of COVID -19 in hospitalized adult and pediatric patients. Application of computational calculations for choosing the sensitive reagent in spectrophotometric quantitative analysis is very limited. Computational and theoretical studies were used for choosing the best acid dye for selective visible spectrophotometric quantitative analysis of remdesivir. The calculations were performed using Gaussian 03 software with the density functional theory method using B3LYP/6-31G(d) basis set. The theoretical studies revealed that bromophenol blue is a better match for remdesivir than other acid dyes due to the higher calculated interaction energy. The proposed method was based on the reaction of remdesivir with the computationally selected acid dye bromophenol blue to form a yellow ion-pair complex. The spectra showed absorption peaks at 418 nm. Various factors affecting the reaction were optimized. The method was successfully applied for the determination of remdesivir in the pharmaceutical preparation with good accuracy and precision. Beer's law was observed in the concentration range of 2-12 μg/mL of remdesivir. The proposed reaction was used as a basis for the spectrophotometric determination of remdesivir in pure form and in the pharmaceutical preparation.

Additional Evidence for Commonalities between COVID-19 and Radiation Injury: Novel Insight into COVID-19 Candidate Drugs

COVID-19 is a challenge to biosecurity and public health. The speed of vaccine development lags behind that of virus evolution and mutation. To date, no agent has been demonstrated to be fully effective against COVID-19. Therefore, it remains of great urgency to rapidly develop promising therapeutic and diagnostic candidates. Intriguingly, mounting evidence hints at parallel etiologies between SARS-CoV-2 infection and radiation injury. Herein, from the perspectives of immunogenic pathway activation and metabolic alterations, we provide novel evidence of commonalities between these two pathological conditions based on the most recent findings. Since numerous agents have been developed to prevent or reverse radiation injury in the past 70 years to ensure nuclear safety, we also advocate investigating the promising function of radioprotectors and radiomitigators against COVID-19 in clinical settings.

Small-Molecule Thioesters as SARS-CoV-2 Main Protease Inhibitors: Enzyme Inhibition, Structure-Activity Relationships, Antiviral Activity, and X-ray Structure Determination

The main protease (Mpro, 3CLpro) of SARS-CoV-2 is an attractive target in coronaviruses because of its crucial involvement in viral replication and transcription. Here, we report on the design, synthesis, and structure-activity relationships of novel small-molecule thioesters as SARS-CoV-2 Mpro inhibitors. Compounds 3w and 3x exhibited excellent SARS-CoV-2 Mpro inhibition with kinac/Ki of 58,700 M-1 s-1 (Ki = 0.0141 μM) and 27,200 M-1 s-1 (Ki = 0.0332 μM), respectively. In Calu-3 and Vero76 cells, compounds 3h, 3i, 3l, 3r, 3v, 3w, and 3x displayed antiviral activity in the nanomolar range without host cell toxicity. Co-crystallization of 3w and 3af with SARS-CoV-2 Mpro was accomplished, and the X-ray structures showed covalent binding with the catalytic Cys145 residue of the protease. The potent SARS-CoV-2 Mpro inhibitors also inhibited the Mpro of other beta-coronaviruses, including SARS-CoV-1 and MERS-CoV, indicating that they might be useful to treat a broader range of coronaviral infections.

COVID-19 and Kidney Transplantation: Epidemiology, Histopathological Presentation, Clinical Presentation and Outcomes, and Therapeutic Strategies

Multiple case series of kidney transplant recipients with COVID-19 have shown increased mortality compared to nontransplant patients. To date, we do not have high-level evidence to inform immunosuppression minimization strategies in infected transplant recipients. Most centers, however, have adopted an early antimetabolite withdrawal in addition to other interventions. The epidemiological problem concerns also dialysis patients and waitlisted patients who have a higher COVID-19 infection diffusion with respect to kidney transplant recipients. Several factors influence mortality among kidney transplant recipients. Among these factors are the age, race, and comorbidity factors, such as hypertension, diabetes mellitus, obesity, and previous respiratory problems. Treatment is still limited. The only effective antiviral drug is remdesivir that should be administered before the development of the cytokine storm. Vaccination seems to be useful, but due to the concomitant immunosuppression limiting its efficacy, at least three or four doses should be administered.

Discovery of new drug indications for COVID-19: A drug repurposing approach

Motivation

The outbreak of coronavirus health issues caused by COVID-19(SARS-CoV-2) creates a global threat to public health. Therefore, there is a need for effective remedial measures using existing and approved therapies with proven safety measures has several advantages. Dexamethasone (Pubchem ID: CID0000005743), baricitinib(Pubchem ID: CID44205240), remdesivir (PubchemID: CID121304016) are three generic drugs that have demonstrated in-vitro high antiviral activity against SARS-CoV-2. The present study aims to widen the search and explore the anti-SARS-CoV-2 properties of these potential drugs while looking for new drug indications with optimised benefits via in-silico research.

Method

Here, we designed a unique drug-similarity model to repurpose existing drugs against SARS-CoV-2, using the anti-Covid properties of dexamethasone, baricitinib, and remdesivir as references. Known chemical-chemical interactions of reference drugs help extract interactive compounds withimprovedanti-SARS-CoV-2 properties. Here, we calculated the likelihood of these drug compounds treating SARS-CoV-2 related symptoms using chemical-protein interactions between the interactive compounds of the reference drugs and SARS-CoV-2 target genes. In particular, we adopted a two-tier clustering approach to generate a drug similarity model for the final selection of potential anti-SARS-CoV-2 drug molecules. Tier-1 clustering was based on t-Distributed Stochastic Neighbor Embedding (t-SNE) and aimed to filter and discard outlier drugs. The tier-2 analysis incorporated two cluster analyses performed in parallel using Ordering Points To Identify the Clustering Structure (OPTICS) and Hierarchical Agglomerative Clustering (HAC). As a result, itidentified clusters of drugs with similar actions. In addition, we carried out a docking study for in-silico validation of top candidate drugs.

Result

Our drug similarity model highlighted ten drugs, including reference drugs that can act as potential therapeutics against SARS-CoV-2. The docking results suggested that doxorubicin showed the least binding energy compared to reference drugs. Their practical utility as anti-SARS-CoV-2 drugs, either individually or in combination, warrants further investigation.

Subcutaneous IL-6 Inhibitor Sarilumab vs. Standard Care in Hospitalized Patients With Moderate-To-Severe COVID-19: An Open Label Randomized Clinical Trial

Background

The use of IL-6 blockers in COVID-19 hospitalized patients has been associated with a reduction in mortality compared to standard care. However, many uncertainties remain pertaining to optimal intervention time, administration schedule, and predictors of response. To date, data on the use of subcutaneous sarilumab is limited and no randomized trial results are available.

Methods

Open label randomized controlled trial at a single center in Spain. We included adult patients admitted with microbiology documented COVID-19 infection, imaging confirmed pneumonia, fever and/or laboratory evidence of inflammatory phenotype, and no need for invasive ventilation. Participants were randomly assigned to receive sarilumab, a single 400 mg dose in two 200 mg subcutaneous injections, added to standard care or standard care, in a 2:1 proportion. Primary endpoints included 30-day mortality, mean change in clinical status at day 7 scored in a 7-category ordinal scale ranging from death (category 1) to discharge (category 7), and duration of hospitalization. The primary efficacy analysis was conducted on the intention-to-treat population.

Results

A total of 30 patients underwent randomization: 20 to sarilumab and 10 to standard care. Most patients were male (20/30, 67%) with a median (interquartile range) age of 61.5 years (56-72). At day 30, 2/20 (10%) patients died in the sarilumab arm vs. none (0/10) in standard care (Log HR 15.11, SE 22.64; p = 0.54). At day 7, no significant differences were observed in the median change in clinical status (2 [0-3]) vs. 3 [0-3], p = 0.32). Median time to discharge (days) was similar (7 [6-11] vs. 6 [4-12]; HR 0.65, SE 0.26; p = 0.27). No significant differences were detected in the rate of progression to invasive and noninvasive mechanical ventilation.

Conclusions and Relevance

Our pragmatic pilot study has failed to demonstrate the benefit of adding subcutaneous sarilumab to standard care for mortality by 30 days, functional status at day 7, or hospital stay. Findings herein do not exclude a potential effect of sarilumab in severe COVID-19 but adequately powered blinded randomized phase III trials are warranted to assess the impact of the subcutaneous route and a more selected target population.

Trial Registration

www.ClinicalTrials.gov, Identifier: NCT04357808.

Use of Remdesivir in the treatment of Coronavirus Disease 2019 (COVID-19) infection among Sudanese patients: a case series

Introduction: The coronavirus disease 2019 (COVID-19) pandemic is affecting populations worldwide. Remdesivir is an anti-retroviral agent, with a broad spectrum of usage. Remdesivir usage against COVID-19 had been studied both in vitro and in vivo but is still considered a new treatment for COVID-19 and is not available in all countries. The aim of our study was to report several cases of the use of Remdesivir in Sudanese patients and report the adverse events related to the course of treatment.

Methods: A case series study was conducted in Imperial Hospital, Khartoum, Sudan reporting two cases who received Remdesivir for treating COVID-19 besides other treatments such as steroids and supportive therapy in December 2020. Cases were males aged over 65 years.

Cases presentation: Both patients were severe cases of COVID-19 admitted to the intensive care unit (ICU), who received Remdesivir for treating COVID-19 infection. Several side effects were reported: the first case had increased liver enzymes and then unexpectedly died from severe resistant hypotension; and hypoalbuminemia was noticed in the second case.

Conclusions: Remdesivir use among patients in Sudan must be studied extensively in order to determine the unexpected fatal event and assess the association of this event to Remdesivir use, as well as to report the frequency of the side effects.

Healthy Immunity on Preventive Medicine for Combating COVID-19

Immunomodulation is influenced by the consumption of nutrients, and healthy immunity is pivotal to defending an individual from a variety of pathogens. The immune system is a network of intricately regulated biological processes that is comprised of many organs, cellular structures, and signaling molecules. A balanced diet, rich in vitamins, minerals, and antioxidants, is key to a strengthened immune system and, thus, crucial to proper functioning of various physiological activities. Conversely, deficiencies of these micronutrients, involving impaired immunity, are linked to numerous health complications, along with a host of pathologies. Coronavirus disease 2019 (COVID-19) is a dangerous infectious disease caused by a β-form of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and its genomic variants, which enter host cells upon binding to the angiotensin converting enzyme 2 receptors, and is associated with substantial morbidities and mortalities globally. Patients afflicted with COVID-19 display asymptomatic to severe symptoms, occurrences of which are multifactorial and include diverse immune responses, sex and gender differences, aging, and underlying medical conditions. Geriatric populations, especially men in comparison to women, regardless of their states, are most vulnerable to severe COVID-19-associated infections and complications, with fatal outcomes. Advances in genomic and proteomic technologies help one understand molecular events, including host–pathogen interactions and pathogenesis of COVID-19 and, subsequently, have developed a variety of preventive measures urgently, ranging from mask wearing to vaccination to medication. Despite these approaches, no unique strategy is available today that can effectively prevent and/or treat this hostile disease. As a consequence, the maintenance of a boosted immune system could be considered a high priority of preventive medicine for combating COVID-19. Herein, we discuss the current level of understanding underlining the contribution of healthy immunity and its relevance to COVID-19 molecular pathogenesis, and potential therapeutic strategies, in the management of this devastating disease.

Targeting SARS-CoV-2 Proteases and Polymerase for COVID-19 Treatment: State of the Art and Future Opportunities

The newly emerged coronavirus, called SARS-CoV-2, is the causing pathogen of pandemic COVID-19. The identification of drugs to treat COVID-19 and other coronavirus diseases is an urgent global need, thus different strategies targeting either virus or host cell are still under investigation. Direct-acting agents, targeting protease and polymerase functionalities, represent a milestone in antiviral therapy. The 3C-like (or Main) protease (3CLpro) and the nsp12 RNA-dependent RNA-polymerase (RdRp) are the best characterized SARS-CoV-2 targets and show the highest degree of conservation across coronaviruses fostering the identification of broad-spectrum inhibitors. Coronaviruses also possess a papain-like protease, another essential enzyme, still poorly characterized and not equally conserved, limiting the identification of broad-spectrum agents. Herein, we provide an exhaustive comparative analysis of SARS-CoV-2 proteases and RdRp with respect to other coronavirus homologues. Moreover, we highlight the most promising inhibitors of these proteins reported so far, including the possible strategies for their further development.

Targeting SARS-CoV-2 Proteases and Polymerase for COVID-19 Treatment: State of the Art and Future Opportunities

The newly emerged coronavirus, called SARS-CoV-2, is the causing pathogen of pandemic COVID-19. The identification of drugs to treat COVID-19 and other coronavirus diseases is an urgent global need, thus different strategies targeting either virus or host cell are still under investigation. Direct-acting agents, targeting protease and polymerase functionalities, represent a milestone in antiviral therapy. The 3C-like (or Main) protease (3CL^pro) and the nsp12 RNA-dependent RNA-polymerase (RdRp) are the best characterized SARS-CoV-2 targets and show the highest degree of conservation across coronaviruses fostering the identification of broad-spectrum inhibitors. Coronaviruses also possess a papain-like protease, another essential enzyme, still poorly characterized and not equally conserved, limiting the identification of broad-spectrum agents. Herein, we provide an exhaustive comparative analysis of SARS-CoV-2 proteases and RdRp with respect to other coronavirus homologues. Moreover, we highlight the most promising inhibitors of these proteins reported so far, including the possible strategies for their further development.

Efficacy and Safety of a Phytopharmaceutical Drug Derived from Cocculus hirsutus in Adults with Moderate COVID-19: a Phase 2, Open-label, Multicenter, Randomized Controlled Trial

Introduction

There is an urgent need for an effective, oral therapy for COVID-19. Purified aqueous extract of Cocculus hirsutus (AQCH) has shown robust antiviral activity in in vitro studies. We aimed to evaluate the efficacy and safety of AQCH plus standard of care in hospitalized patients with moderate COVID-19.

Methods

In an open-label, multicenter, randomized controlled trial conducted in India, eligible patients (aged 18–75 years) were randomized (1:1) to receive AQCH 400 mg orally three times a day plus standard of care (AQCH group) or standard of care alone (control group) for 10 days. Primary endpoint was the proportion of patients showing clinical improvement by day 14. Time to clinical improvement, time to viral clearance, and duration of hospitalization were secondary endpoints.

Results

A total of 210 patients were randomized. By day 14 most patients in both groups showed clinical improvement [difference − 0.01 (95% CI − 0.07 to 0.05); p = 1.0]. Median time to clinical improvement was 8 days (IQR 8–11) in the AQCH group versus 11 days (IQR 8–11) in the control group [HR 1.27 (95% CI 0.95–1.71); p = 0.032]. Time to viral clearance and duration of hospitalization were also significantly shorter in the AQCH group (p = 0.0002 and p = 0.016, respectively). AQCH was well tolerated, with no safety concerns identified.

Conclusions

AQCH significantly reduced time to clinical improvement, time to viral clearance, and duration of hospitalization. In a pandemic, this has significant potential to decrease healthcare resource utilization and increase hospital bed availability. Further investigation of the therapeutic potential of AQCH in patients with COVID-19 is warranted.

Trial Registration

Clinical Trials Registry – India (CTRI/2020/05/025397).

Supplementary Information

The online version contains supplementary material available at 10.1007/s40121-022-00604-0.

COVID-19 in a mosaic trisomy 13 patient with polycystic kidney disease

Presentation, management, and outcomes of COVID-19 infections among younger patients is an area of medicine with deficits in research, likely due to the lower incidence of severe COVID-19 disease among the younger population. Management can be challenging, and clinicians often guide their decision-making based on the ever-changing protocols that are tailored mostly to the elderly population. Even more underrepresented in COVID-19 research are patients with chromosomal abnormalities and trisomy syndromes, as they appear less frequently, but have risk of increased morbidity and mortality due to underlying medical conditions. We describe a case of severe COVID-19 infection in a young patient with mosaic trisomy 13 and pre-existing polycystic kidney disease, who developed severe acute hypoxic respiratory failure and acute chronic kidney injury. The patient was provided maximal pharmacological support and her clinical course helps to shape the understanding of COVID-19 infections in the setting of chromosomal abnormalities and complex medical history.

Perspectives of association Baricitinib/Remdesivir for adults with Covid-19 infection

BACKGROUND

The global COVID-19 pandemic is currently underway. A massive worldwide vaccination campaign is still underway, representing the most promising weapon available to stop the pandemic.

METHODS AND RESULTS

However, research continues to investigate the most effective drug treatments to reduce and avoid the most serious complications caused by COVID-19 infection. Recently, new evidence of good therapeutic efficacy against COVID-19 has emerged for the antiviral Remdesivir and the immunomodulatory Baricitinib, also in combination. The first one showed SARS-CoV-2 antireplicative activity, the second one useful to reduce the hyperinflammatory state caused by cytokine storm in the most severe phases of the infection.

CONCLUSIONS

In this short communication we describe the molecular pharmacological mechanisms and the latest evidence for the use of these therapeutic agents in the treatment of COVID-19 infection.

Efficacy of the early treatment with tocilizumab-hydroxychloroquine and tocilizumab-remdesivir in severe COVID-19 Patients

BACKGROUND

The effectiveness of the best combination between different antiviral and anti-inflammatory drugs stills an interest in the treatment of COVID19 infection.

PATIENTS AND METHODS

A prospective randomized cohort study comprised 108 adult patients with confirmed PCR COVID 19 infection with systemic hyper inflammation state, divided into two groups according to the treatment regimen, 56 in the tocilizumab- hydroxychloroquine (TCZ-HCQ) treatment, and 52 in the tocilizumab-remdesivir (TCZ-RMV) treatment. The first group received a combination of I.V. TCZ (400-800 mg every 24 h for only two doses) and HCQ (400 mg twice in the first day then 200 mg twice for 5 days) while the second group of patients received I.V. RMV of 200 mg on day 1 followed by 100 mg once daily infused over 60 min for 5 days with the same TCZ regimen used in the first group. All clinical parameters and laboratory investigations were assessed before and after treatment.

RESULTS

The CRP was significantly decreased while PaO2/FiO2 (P/F) ratio post-treatment was significantly improved in both treatment groups. TCZ-HCQ group showed a significant decrease in the ferritin, LDH, and D. Dimer levels. The median days of hospitalization with interquartile range (IQR) were 10 (6-16) and 8 (5-12) for TCZ-HCQ and TCZ-RMV groups, respectively. The numbers of mechanically ventilated patients were 25 and 43 for TCZ-HCQ and TCZ-RMV groups, respectively. Therapeutic failure was about 26.8% in the TCZ-HCQ group and 30.8% in the TCZ-RMV group but there was no significant difference between both groups. Some complications were recognized only in TCZ-RMV following treatment including secondary bacterial infections (42.3%), myocarditis (15.4%), and finally pulmonary embolism (7.7%).

CONCLUSION

Efficacy of both TCZ-RMV and TCZ-HCQ combinations are observed in the treatment of severe COVID-19 patients; however the increased need for ICU or mechanical ventilation in the TCZ-RMV arm contributed to the appearance of cardiac and thrombotic events. The study was registered at the Clinical Trials registry (ClinicalTrials.gov; NCT04779047).

In vivo pharmacokinetic study of remdesivir dry powder for inhalation in hamsters

Remdesivir dry powder for inhalation was previously developed using thin film freezing (TFF). A single-dose 24-h pharmacokinetic study in hamsters demonstrated that pulmonary delivery of TFF remdesivir can achieve plasma remdesivir and GS-441524 levels higher than the reported EC₅₀s of both remdesivir and GS-441524 (in human epithelial cells) over 20 h. The half-life of GS-4412524 following dry powder insufflation was about 7 h, suggesting the dosing regimen would be twice-daily administration. Although the remdesivir-Captisol® (80/20 w/w) formulation showed faster and greater absorption of remdesivir and GS-4412524 in the lung, remdesivir-leucine (80/20 w/w) exhibited a greater C_max with shorter T_max and lower AUC of GS-441524, indicating lower total drug exposure is required to achieve a high effective concentration against SAR-CoV-2. In conclusion, remdesivir dry powder for inhalation would be a promising alternative dosage form for the treatment of COVID-19 disease.

In silico identification of SARS-CoV-2 cell entry inhibitors from selected natural antivirals

The aim of this study is to identify potential drug-like molecules against SARS-CoV-2 virus among the natural antiviral compounds published in the Encyclopedia of Traditional Chinese Medicine. To test inhibition capability of these compounds first, we docked them with Spike protein, angiotensin-converting enzyme 2 (ACE2) (PDB ID: 6M0J) and neuropilin 1 (NRP1) (PDB ID: 7JJC) receptors, and found significant docking scores with extra precision up to -11 kcal/mol. Then, their stability in the binding pockets were further evaluated with molecular dynamics simulation. Eight natural antiviral compounds were identified as potential inhibitors against SARS-CoV-2 cell entry after 200 ns molecular dynamics simulations. We found CMP-3, CMP-4, CMP-5, CMP-6 and CMP-8 are strong binders for the spike protein, CMP-1, CMP-2, CMP-4, CMP-5 and CMP-7 are strong binders for the neuropilin receptor, and CMP-5 is a strong binder for the ACE2. Quercetin derivatives (CMP-4, CMP-5, CMP-6 and CMP-7) were found highly stable in the active domain of NRP1, ACE2 and Spike protein. Especially, CMP-5 showed an inhibitory activity for all targets. These natural antivirals may be potential drug candidates for the prevention of SARS-CoV-2 infection.

Drug Repurposing to Identify Nilotinib as a Potential SARS-CoV-2 Main Protease Inhibitor: Insights from a Computational and In Vitro Study

COVID-19, an acute viral pneumonia, has emerged as a devastating pandemic. Drug repurposing allows researchers to find different indications of FDA-approved or investigational drugs. In this current study, a sequence of pharmacophore and molecular modeling-based screening against COVID-19 Mpro (PDB: 6LU7) suggested a subset of drugs, from the Drug Bank database, which may have antiviral activity. A total of 44 out of 8823 of the most promising virtual hits from the Drug Bank were subjected to molecular dynamics simulation experiments to explore the strength of their interactions with the SARS-CoV-2 Mpro active site. MD findings point toward three drugs (DB04020, DB12411, and DB11779) with very low relative free energies for SARS-CoV-2 Mpro with interactions at His41 and Met49. MD simulations identified an additional interaction with Glu166, which enhanced the binding affinity significantly. Therefore, Glu166 could be an interesting target for structure-based drug design. Quantitative structural-activity relationship analysis was performed on the 44 most promising hits from molecular docking-based virtual screening. Partial least square regression accurately predicted the values of independent drug candidates' binding energy with impressively high accuracy. Finally, the EC50 and CC50 of 10 drug candidates were measured against SARS-CoV-2 in cell culture. Nilotinib and bemcentinib had EC50 values of 2.6 and 1.1 μM, respectively. In summary, the results of our computer-aided drug design provide a roadmap for rational drug design of Mpro inhibitors and the discovery of certified medications as COVID-19 antiviral therapeutics.

Molecular Mechanisms of SARS-CoV-2/COVID-19 Pathogenicity on the Central Nervous System: Bridging Experimental Probes to Clinical Evidence and Therapeutic Interventions

The coronavirus disease 2019 (COVID-19) pandemic, induced by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has dramatically impacted the global healthcare systems, constantly challenging both research and clinical practice. Although it was initially believed that the SARS-CoV-2 infection is limited merely to the respiratory system, emerging evidence indicates that COVID-19 affects multiple other systems including the central nervous system (CNS). Furthermore, most of the published clinical studies indicate that the confirmed CNS inflammatory manifestations in COVID-19 patients are meningitis, encephalitis, acute necrotizing encephalopathy, acute transverse myelitis, and acute disseminated encephalomyelitis. In addition, the neuroinflammation along with accelerated neurosenescence and susceptible genetic signatures in COVID-19 patients might prime the CNS to neurodegeneration and precipitate the occurrence of neurodegenerative diseases, including Alzheimer's and Parkinson's diseases. Thus, this review provides a critical evaluation and interpretive analysis of existing published preclinical as well as clinical studies on the key molecular mechanisms modulating neuroinflammation and neurodegeneration induced by the SARS-CoV-2. In addition, the essential age- and gender-dependent impacts of SARS-CoV-2 on the CNS of COVID-19 patients are also discussed.

Myasthenic Crisis After Recurrent COVID-19 Infection

A patient with myasthenia gravis who survived 2 COVID-19 infections required plasmapheresis to recover from an acute crisis.

Clinical trials with antiviral drugs against COVID-19: some progress and many shattered hopes

Vaccines and drugs are the cornerstones in the fight against the SARS-CoV-2 pandemic. While vaccines were a success story, the development of antiviral drugs against SARS-CoV-2 turned out to be difficult. For an accelerated use of antivirals in the clinic, most SARS-CoV-2 antivirals represented repurposed drugs. The present article summarizes the outcomes of clinical trials with antiviral drugs in COVID-19 patients. Many antiviral drugs failed to demonstrate beneficial effects or showed mixed results. One reason for the low success rate of clinical trials was shortcomings of antiviral tests in cell culture systems and another reason was the abundance of ill-coordinated and underpowered clinical trials. However, large pragmatic clinical trials particularly of the British RECOVERY trial series demonstrated that even under emergency situation drug trials can be conducted in a timely way such that the therapy of COVID-19 patients can be based on evidence basis instead on expert opinion or even worse on political pressure.

Association and pharmacological synergism of the triple drug therapy baricitinib/remdesivir/rhACE2 for the management of COVID-19 infection

A massive vaccination campaign against the global COVID-19 pandemic caused by SARS-CoV-2 virus began worldwide in January 2021. However, studies continue to investigate the most effective and safe drug therapies to manage the various stages of viral infection. It is critical in the therapeutic management of the patient, with ongoing COVID-19 infection, to reduce viral load and replication, and to regulate the generalized hyperinflammatory state caused by the cytokine storm that occurs in the most severe phases. Probably the right drug therapy is represented by the use of different drugs acting in different modalities and on different targets, to avoid also viral drug resistance. In this article, we describe an interesting scientific pharmacological hypothesis arising from the evidence in the literature; we believe that the association of baricitinib/remdesivir/rhACE2, administered at the right time and dose, represents an important pharmacological synergism that can be therapeutically more effective for the treatment of COVID-19 infection than the single administration of drugs and avoid the phenomenon of drug resistance caused by the virus.

A new perspective on SARS-CoV-2 management

Baricitinib/remdesivir/rhACE2 may have an effective synergism of action

Avoiding viral drug resistance is of paramount importance

Indole Chloropyridinyl Ester-Derived SARS-CoV-2 3CLpro Inhibitors: Enzyme Inhibition, Antiviral Efficacy, Structure-Activity Relationship, and X-ray Structural Studies

Here, we report the synthesis, structure-activity relationship studies, enzyme inhibition, antiviral activity, and X-ray crystallographic studies of 5-chloropyridinyl indole carboxylate derivatives as a potent class of SARS-CoV-2 chymotrypsin-like protease inhibitors. Compound 1 exhibited a SARS-CoV-2 3CLpro inhibitory IC50 value of 250 nM and an antiviral EC50 value of 2.8 μM in VeroE6 cells. Remdesivir, an RNA-dependent RNA polymerase inhibitor, showed an antiviral EC50 value of 1.2 μM in the same assay. Compound 1 showed comparable antiviral activity with remdesivir in immunocytochemistry assays. Compound 7d with an N-allyl derivative showed the most potent enzyme inhibitory IC50 value of 73 nM. To obtain molecular insight into the binding properties of these molecules, X-ray crystal structures of compounds 2, 7b, and 9d-bound to SARS-CoV 3CLpro were determined, and their binding properties were compared.

SARS-CoV-2 monoclonal antibodies with therapeutic potential: Broad neutralizing activity and No evidence of antibody-dependent enhancement

Monoclonal antibodies (mAbs) are emerging as safe and effective therapeutics against SARS-CoV-2. However, variant strains of SARS-CoV-2 have evolved, with early studies showing that some mAbs may not sustain their efficacy in the face of escape mutants. Also, from the onset of the COVID-19 pandemic, concern has been raised about the potential for Fcγ receptor-mediated antibody-dependent enhancement (ADE) of infection. In this study, plaque reduction neutralization assays demonstrated that mAb 1741-LALA neutralizes SARS-CoV-2 strains B.1.351, D614 and D614G. MAbs S1D2-hIgG1 and S1D2-LALA mutant (STI-1499-LALA) did not neutralize B.1.351, but did neutralize SARS-CoV-2 strains D614 and D614G. LALA mutations did not result in substantial differences in neutralizing abilities between clones S1D2-hIgG1 vs STI-1499-LALA. S1D2-hIgG1, STI-1499-LALA, and convalescent plasma showed minimal ability to induce ADE in human blood monocyte-derived macrophages. Further, no differences in pharmacokinetic clearance of S1D2-hIgG1 vs STI-1499-LALA were observed in mice expressing human FcRn. These findings confirm that SARS-CoV-2 has already escaped some mAbs, and identify a mAb candidate that may neutralize multiple SARS-CoV-2 variants. They also suggest that risk of ADE in macrophages may be low with SARS-CoV-2 D614, and LALA Fc change impacts neither viral neutralization nor Ab clearance.

COVID-19 Infection Clinical Profile, Management, Outcome, and Antibody Response in Kidney Transplant Recipients: A Single Centre Experience

INTRODUCTION

Experience of COVID-19 in kidney transplant recipients (KTRs) with clinical presentation, management, factors influencing mortality, and antibody response is limited. Material and Methods. A retrospective data of COVID-19 in KTRs was collected and analyzed. The mortality rate, risk factors, and antibody response were primary objectives, while the clinical presentation, laboratory indicators, and pharmacological management were secondary objectives.

RESULTS

The 67 KTRs with polymerase chain reaction (PCR) confirmed COVID-19 infection reported between 1 May 2020 and 31 December 2020; 61.2% of patients were hospitalized; and 20.9% needed ventilation. The overall mortality was 26.9%, while blood group A had 50% mortality. The treatment options and used were steroids (100%), convalescent plasma (32.8%), ivermectin (58.2%), doxycycline (55.2%), remdesivir (34.3%), tocilizumab (10.4%), antibiotics (61.2%), anti-fungals (26.9%), low molecular weight heparin (45.3%), and oral anti-coagulants (26.9%). Anti-nucleosides (mycophenolate or azathioprine) were discontinued in 76.1% and calcineurin inhibitors (CNI) in 26.9%. Significant mortality (p < 0.001) was observed in patients presenting with SpO2 <94 needing ICU care, ventilation, dialysis/acute kidney injury (AKI), and empirical therapies like convalescent plasma and remdesivir. The age of survivors versus nonsurvivors was not significantly different (p=0.02). The positive blood culture, low serum albumin, high TLC, high blood urea, interleukin-6, and CT severity score ≥15 were statistically significant in nonsurvivors. Overall mortality, mortality of hospitalized patients, and mortality of ventilated patients was 27%, 44%, and 100%, respectively. The median value of SARS-CoV-2 (COVID-19) IgG antibody was 68.60 (IQR, 28.5-94.25) AU/ml in more than 90% of survivors.

CONCLUSION

KTRs with COVID-19, needing ICU care, dialysis and ventilation support had poor outcomes. Recovered patients mounted adequate antibody response.

Chloropyridinyl Esters of Nonsteroidal Anti-Inflammatory Agents and Related Derivatives as Potent SARS-CoV-2 3CL Protease Inhibitors

We report the design and synthesis of a series of new 5-chloropyridinyl esters of salicylic acid, ibuprofen, indomethacin, and related aromatic carboxylic acids for evaluation against SARS-CoV-2 3CL protease enzyme. These ester derivatives were synthesized using EDC in the presence of DMAP to provide various esters in good to excellent yields. Compounds are stable and purified by silica gel chromatography and characterized using 1H-NMR, 13C-NMR, and mass spectral analysis. These synthetic derivatives were evaluated in our in vitro SARS-CoV-2 3CLpro inhibition assay using authentic SARS-CoV-2 3CLpro enzyme. Compounds were also evaluated in our in vitro antiviral assay using quantitative VeroE6 cell-based assay with RNAqPCR. A number of compounds exhibited potent SARS-CoV-2 3CLpro inhibitory activity and antiviral activity. Compound 9a was the most potent inhibitor, with an enzyme IC50 value of 160 nM. Compound 13b exhibited an enzyme IC50 value of 4.9 µM. However, it exhibited a potent antiviral EC50 value of 24 µM in VeroE6 cells. Remdesivir, an RdRp inhibitor, exhibited an antiviral EC50 value of 2.4 µM in the same assay. We assessed the mode of inhibition using mass spectral analysis which suggested the formation of a covalent bond with the enzyme. To obtain molecular insight, we have created a model of compound 9a bound to SARS-CoV-2 3CLpro in the active site.

Understanding the SARS-CoV-2 virus to mitigate current and future pandemic(s)

Micro-organisms form the first pioneer community in the history of biological life, thought to be present in the primordial soup and evolving later with more complex life-forms. Among micro-organisms, viruses form a separate taxon of organisms. Viruses are obligate parasites, being inactive without a host and becoming active once in contact with specific hosts. Viruses, with an inherent ability to infect and hijack cellular structures, have been utilised as vectors to introduce foreign genetic material in a variety of biological species, e.g. adenoviral vectors. However, viruses have also been the root cause of many infectious diseases, most notable being HIV-AIDS, for its resistance to treatment and omnipresent occurrence. There are many families of viruses like retroviridae, picornaviridae and poxviridae. This review focuses on a specific member of the coronaviridae, the SARS-CoV-2. This virus is responsible for the current COVID-19 pandemic. This review summarises its transmission, molecular mechanism by which it causes disease, associated clinical symptoms and the strategies available to control it from sources like PubMed, Google Scholar, webservers of National Institute of Health (NIH), European Molecular Biology Laboratory (EMBL), World Health Organisation (WHO), United States Food and Drug Administration (USFDA) and Centers for Disease Control and Prevention (CDC) available as on 1st May 2021.

Hypertension as a manifestation of COVID-19 pneumonia

Several factors such as hypertension, bile duct disease, and age can affect the duration of COVID, which can lead to long COVID. Any course of coronavirus infection could have a diverse nature of clinical forms and should have a personalized approach.

Sex-tailored pharmacology and COVID-19: Next steps towards appropriateness and health equity

Making gender bias visible allows to fill the gaps in knowledge and understand health records and risks of women and men. The coronavirus disease 2019 (COVID-19) pandemic has shown a clear gender difference in health outcomes. The more severe symptoms and higher mortality in men as compared to women are likely due to sex and age differences in immune responses. Age-associated decline in sex steroid hormone levels may mediate proinflammatory reactions in older adults, thereby increasing their risk of adverse outcomes, whereas sex hormones and/or sex hormone receptor modulators may attenuate the inflammatory response and provide benefit to COVID-19 patients. While multiple pharmacological options including anticoagulants, glucocorticoids, antivirals, anti-inflammatory agents and traditional Chinese medicine preparations have been tested to treat COVID-19 patients with varied levels of evidence in terms of efficacy and safety, information on sex-targeted treatment strategies is currently limited. Women may have more benefit from COVID-19 vaccines than men, despite the occurrence of more frequent adverse effects, and long-term safety data with newly developed vectors are eagerly awaited. The prevalent inclusion of men in randomized clinical trials (RCTs) with subsequent extrapolation of results to women needs to be addressed, as reinforcing sex-neutral claims into COVID-19 research may insidiously lead to increased inequities in health care. The huge worldwide effort with over 3000 ongoing RCTs of pharmacological agents should focus on improving knowledge on sex, gender and age as pillars of individual variation in drug responses and enforce appropriateness.

Targeting Some Enzymes with Repurposing Approved Pharmaceutical Drugs for Expeditious Antiviral Approaches Against Newer Strains of COVID-19

At present, global vaccination for the SARS-CoV2 virus 2019 (COVID-19) is 95% effective. Generally, viral infections are arduous to cure due to the mutating nature of viral genomes, with the consequent quick development of resistance, posing significant fatalities or hazards. The novel corona viral strains are increasingly lethal than earlier variants, as those evolve faster than imagined. Despite the emergence of several present innovative treatment options, the vaccines, and available drugs, the latter still are the needs of the time. Therefore, repurposing the approved pharmaceutical drugs of a well-known safety profile would be ascertained to provide faster antiviral approaches for the newer strains of COVID-19. Recently, a combination of remdesivir, which has a competitively inhibitory effect on the nucleotide uptake in the virus, and the merimepodibs, an inhibitor of the enzyme inosine monophosphate dehydrogenase, which has a role in the synthesis of nucleotides of guanine bases, is in use in phase 2 clinical trials. However, new investigations suggest that using remdesivir, there is no statistically significant difference with uncertain clinical importance for moderate COVID-19 patients. Herein, an intellectual selection of approved drugs based on the safety profile is described, to target any essential enzymes that are required for the virus-receptor contact, fusion, and/or different stages of the life cycle of this virus, should help to screen drugs against newer strains of COVID-19.

Graphical abstract

Deep learning identifies antigenic determinants of severe SARS-CoV-2 infection within T-cell repertoires

SARS-CoV-2 infection is characterized by a highly variable clinical course with patients experiencing asymptomatic infection all the way to requiring critical care support. This variation in clinical course has led physicians and scientists to study factors that may predispose certain individuals to more severe clinical presentations in hopes of either identifying these individuals early in their illness or improving their medical management. We sought to understand immunogenomic differences that may result in varied clinical outcomes through analysis of T-cell receptor sequencing (TCR-Seq) data in the open access ImmuneCODE database. We identified two cohorts within the database that had clinical outcomes data reflecting severity of illness and utilized DeepTCR, a multiple-instance deep learning repertoire classifier, to predict patients with severe SARS-CoV-2 infection from their repertoire sequencing. We demonstrate that patients with severe infection have repertoires with higher T-cell responses associated with SARS-CoV-2 epitopes and identify the epitopes that result in these responses. Our results provide evidence that the highly variable clinical course seen in SARS-CoV-2 infection is associated to certain antigen-specific responses.

Influenza virus and SARS-CoV-2: pathogenesis and host responses in the respiratory tract

Influenza viruses cause annual epidemics and occasional pandemics of respiratory tract infections that produce a wide spectrum of clinical disease severity in humans. The novel betacoronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged in December 2019 and has since caused a pandemic. Both viral and host factors determine the extent and severity of virus-induced lung damage. The host's response to viral infection is necessary for viral clearance but may be deleterious and contribute to severe disease phenotypes. Similarly, tissue repair mechanisms are required for recovery from infection across the spectrum of disease severity; however, dysregulated repair responses may lead to chronic lung dysfunction. Understanding of the mechanisms of immunopathology and tissue repair following viral lower respiratory tract infection may broaden treatment options. In this Review, we discuss the pathogenesis, the contribution of the host response to severe clinical phenotypes and highlight early and late epithelial repair mechanisms following influenza virus infection, each of which has been well characterized. Although we are still learning about SARS-CoV-2 and its disease manifestations in humans, throughout the Review we discuss what is known about SARS-CoV-2 in the context of this broad knowledge of influenza virus, highlighting the similarities and differences between the respiratory viruses.

Does Covera-19 know 'when to hold 'em or 'when to fold 'em? A translational thought experiment

The function of proteins depends on their structure. The structural integrity of proteins is dynamic and depends on interacting nearby neighboring moieties that influence their properties and induce folding and structural changes. The conformational changes induced by these nearby neighbors in the micro-environmental milieu at that moment are guided by chemical or electrical bonding attractions. There are few literature references that describe the potential for environmental milieu changes to disfavor SARS-CoV-2 attachment to a receptor for survival outside of a host. There are many studies on the effects of pH (acid and base balance) supporting its importance for protein structure and function, but few focus on pH role in extracellular or intracellular protein or actionable requirements of Covera-19. 'Fold 'em or Hold 'em' is seen by the various functions and effects of furin as it seeks an acidic milieu for action or compatible amino acid sequences which is currently aided by its histidine component and the structural changes of proteins as they enter or exit the host. Questions throughout the text are posed to focus on current thoughts as reviewing applicable COVID-19 translational research science in order to understand the complexities of Covid-19. The pH needs of COVID-19 players and its journey through the human host and environment as well as some efficacious readily available repurposed drugs and out-of-the box and easily available treatments are reviewed.

Use of Remdesivir in the treatment of Coronavirus Disease 2019 (COVID-19) infection among Sudanese patients: a case series

Introduction: The coronavirus disease 2019 (COVID-19) pandemic is affecting populations worldwide. Remdesivir is an anti-retroviral agent, with a broad spectrum of usage. Remdesivir usage against COVID-19 had been studied both in vitro and in vivo but is still considered a new treatment for COVID-19 and is not available in all countries. The aim of our study was to report several cases of the use of Remdesivir in Sudanese patients and report the adverse events related to the course of treatment. Methods: A case series study was conducted in Imperial Hospital, Khartoum, Sudan reporting two cases who received Remdesivir for treating COVID-19 besides other treatments such as steroids and supportive therapy in December 2020. Cases were males aged over 65 years. Cases presentation: Both patients were severe cases of COVID-19 admitted to the intensive care unit (ICU), who received Remdesivir for treating COVID-19 infection. Several side effects were reported: the first case had increased liver enzymes and then unexpectedly died from severe resistant hypotension; and hypoalbuminemia was noticed in the second case. Conclusions: Remdesivir use among patients in Sudan must be studied extensively in order to determine the unexpected fatal event and assess the association of this event to Remdesivir use, as well as to report the frequency of the side effects.

Natural Products, Alone or in Combination with FDA-Approved Drugs, to Treat COVID-19 and Lung Cancer

As a public health emergency of international concern, the highly contagious coronavirus disease 2019 (COVID-19) pandemic has been identified as a severe threat to the lives of billions of individuals. Lung cancer, a malignant tumor with the highest mortality rate, has brought significant challenges to both human health and economic development. Natural products may play a pivotal role in treating lung diseases. We reviewed published studies relating to natural products, used alone or in combination with US Food and Drug Administration-approved drugs, active against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and lung cancer from 1 January 2020 to 31 May 2021. A wide range of natural products can be considered promising anti-COVID-19 or anti-lung cancer agents have gained widespread attention, including natural products as monotherapy for the treatment of SARS-CoV-2 (ginkgolic acid, shiraiachrome A, resveratrol, and baicalein) or lung cancer (daurisoline, graveospene A, deguelin, and erianin) or in combination with FDA-approved anti-SARS-CoV-2 agents (cepharanthine plus nelfinavir, linoleic acid plus remdesivir) and anti-lung cancer agents (curcumin and cisplatin, celastrol and gefitinib). Natural products have demonstrated potential value and with the assistance of nanotechnology, combination drug therapies, and the codrug strategy, this "natural remedy" could serve as a starting point for further drug development in treating these lung diseases.

Evaluating Clinical Efficacy of Antiviral Therapy for COVID-19: A Surrogate Endpoint Approach

INTRODUCTION

Efficient evaluation with an early surrogate endpoint, taking into account the process of disease evolution, may not only clarify inconsistent or underpowered results but also provide a new insight into the exploration of a new antiviral therapy for treating COVID-19 patients.

METHODS

We assessed the dynamics of COVID-19 disease spectrum, commencing from low-risk (no or low oxygen supplement), medium-risk (non-invasive ventilator or high oxygen supplement), and high-risk (extracorporeal membrane oxygenation or invasive ventilator) risk state on enrollment, and then the subsequent progression and regression of risk states until discharge or death. The efficacy of antiviral therapy in altering the dynamics was assessed by using the high-risk state as a surrogate endpoint based on the data retrieved from the two-arm Adaptive Covid-19 Treatment Trial.

RESULTS

Using the high-risk state as a surrogate endpoint, remdesivir treatment led to a decrease in the high-risk COVID-19 state by 34.8% (95% CI 26.7-42.0%) for a 14-day period and 29.3% (95% CI 28.8-29.8%) up to 28 days, which were consistent with a statistically significant reduction of death by 30.5% (95% CI 6.6, 50.9%) up to a 28-day period. The estimates of numbers needed to be treated were 100.9 (95% CI 88.1, 115.7) for using the high-risk COVID-19 state as a surrogate endpoint for a 14-day period and 133.3 (95% CI 112.5, 158.0) were required for averting one death from COVID-19 up to 28 days.

CONCLUSIONS

We demonstrate the expedient use of the high-risk COVID-19 disease status as a surrogate endpoint for evaluating the primary outcome of the earliest death.

Assessing efficacy of antiviral therapy for COVID-19 patients: A case study on remdesivir with bayesian synthesis design and multistate analysis

BACKGROUND/PURPOSE

A synthesis design and multistate analysis is required for assessing the clinical efficacy of antiviral therapy on dynamics of multistate disease progression and in reducing the mortality and enhancing the recovery of patients with COVID-19. A case study on remdesivir was illustrated for the clinical application of such a novel design and analysis.

METHODS

A Bayesian synthesis design was applied to integrating the empirical evidence on the one-arm compassion study and the two-arm ACTT-1 trial for COVID-19 patients treated with remdesivir. A multistate model was developed to model the dynamics of hospitalized COVID-19 patients from three transient states of low, medium-, and high-risk until the two outcomes of recovery and death. The outcome measures for clinical efficacy comprised high-risk state, death, and discharge.

RESULTS

The efficacy of remdesivir in reducing the risk of death and enhancing the odds of recovery were estimated as 31% (95% CI, 18-44%) and 10% (95% CI, 1-18%), respectively. Remdesivir therapy for patients with low-risk state showed the efficacy in reducing subsequent progression to high-risk state and death by 26% (relative rate (RR), 0.74; 95% CI, 0.55-0.93) and 62% (RR, 0.38; 95% CI, 0.29-0.48), respectively. Less but still statistically significant efficacy in mortality reduction was noted for the medium- and high-risk patients. Remdesivir treated patients had a significantly shorter period of hospitalization (9.9 days) compared with standard care group (12.9 days).

CONCLUSION

The clinical efficacy of remdesvir therapy in reducing mortality and accelerating discharge has been proved by the Bayesian synthesis design and multistate analysis.