Role of lopinavir/ritonavir in the treatment of SARS: initial virological and clinical findings

Epidemiological and clinical features of the 2019 novel coronavirus outbreak in China.. [PMID: 0 DOI: 10.1101/2020.02.10.20021675]

Our manuscript was based on surveillance cases of COVID-19 identified before January 26, 2020. As of February 20, 2020, the total number of confirmed cases in mainland China has reached 18 times of the number in our manuscript. While the methods and the main conclusions in our original analyses remain solid, we decided to withdraw this preprint for the time being, and will replace it with a more up-to-date version shortly. Should you have any comments or suggestions, please feel free to contact the corresponding author.

A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version)

In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province; and then named "2019 novel coronavirus (2019-nCoV)" by the World Health Organization (WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world's attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development; we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control (including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.

A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version)

In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province; and then named "2019 novel coronavirus (2019-nCoV)" by the World Health Organization (WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world's attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development; we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control (including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.

A rapid advice guideline for the diagnosis and treatment of 2019 novel coronavirus (2019-nCoV) infected pneumonia (standard version)

In December 2019, a new type viral pneumonia cases occurred in Wuhan, Hubei Province; and then named "2019 novel coronavirus (2019-nCoV)" by the World Health Organization (WHO) on 12 January 2020. For it is a never been experienced respiratory disease before and with infection ability widely and quickly, it attracted the world's attention but without treatment and control manual. For the request from frontline clinicians and public health professionals of 2019-nCoV infected pneumonia management, an evidence-based guideline urgently needs to be developed. Therefore, we drafted this guideline according to the rapid advice guidelines methodology and general rules of WHO guideline development; we also added the first-hand management data of Zhongnan Hospital of Wuhan University. This guideline includes the guideline methodology, epidemiological characteristics, disease screening and population prevention, diagnosis, treatment and control (including traditional Chinese Medicine), nosocomial infection prevention and control, and disease nursing of the 2019-nCoV. Moreover, we also provide a whole process of a successful treatment case of the severe 2019-nCoV infected pneumonia and experience and lessons of hospital rescue for 2019-nCoV infections. This rapid advice guideline is suitable for the first frontline doctors and nurses, managers of hospitals and healthcare sections, community residents, public health persons, relevant researchers, and all person who are interested in the 2019-nCoV.

Therapeutic strategies in an outbreak scenario to treat the novel coronavirus originating in Wuhan, China

A novel coronavirus (2019-nCoV) originating in Wuhan, China presents a potential respiratory viral pandemic to the world population. Current efforts are focused on containment and quarantine of infected individuals. Ultimately, the outbreak could be controlled with a protective vaccine to prevent 2019-nCoV infection. While vaccine research should be pursued intensely, there exists today no therapy to treat 2019-nCoV upon infection, despite an urgent need to find options to help these patients and preclude potential death. Herein, I review the potential options to treat 2019-nCoV in patients, with an emphasis on the necessity for speed and timeliness in developing new and effective therapies in this outbreak. I consider the options of drug repurposing, developing neutralizing monoclonal antibody therapy, and an oligonucleotide strategy targeting the viral RNA genome, emphasizing the promise and pitfalls of these approaches. Finally, I advocate for the fastest strategy to develop a treatment now, which could be resistant to any mutations the virus may have in the future. The proposal is a biologic that blocks 2019-nCoV entry using a soluble version of the viral receptor, angiotensin-converting enzyme 2 (ACE2), fused to an immunoglobulin Fc domain (ACE2-Fc), providing a neutralizing antibody with maximal breath to avoid any viral escape, while also helping to recruit the immune system to build lasting immunity. The ACE2-Fc therapy would also supplement decreased ACE2 levels in the lungs during infection, thereby directly treating acute respiratory distress pathophysiology as a third mechanism of action. The sequence of the ACE2-Fc protein is provided to investigators, allowing its possible use in recombinant protein expression systems to start producing drug today to treat patients under compassionate use, while formal clinical trials are later undertaken. Such a treatment could help infected patients before a protective vaccine is developed and widely available in the coming months to year(s).

Therapeutic strategies in an outbreak scenario to treat the novel coronavirus originating in Wuhan, China

A novel coronavirus (2019-nCoV) originating in Wuhan, China presents a potential respiratory viral pandemic to the world population. Current efforts are focused on containment and quarantine of infected individuals. Ultimately, the outbreak could be controlled with a protective vaccine to prevent 2019-nCoV infection. While vaccine research should be pursued intensely, there exists today no therapy to treat 2019-nCoV upon infection, despite an urgent need to find options to help these patients and preclude potential death. Herein, I review the potential options to treat 2019-nCoV in patients, with an emphasis on the necessity for speed and timeliness in developing new and effective therapies in this outbreak. I consider the options of drug repurposing, developing neutralizing monoclonal antibody therapy, and an oligonucleotide strategy targeting the viral RNA genome, emphasizing the promise and pitfalls of these approaches. Finally, I advocate for the fastest strategy to develop a treatment now, which could be resistant to any mutations the virus may have in the future. The proposal is a biologic that blocks 2019-nCoV entry using a soluble version of the viral receptor, angiotensin-converting enzyme 2 (ACE2), fused to an immunoglobulin Fc domain, providing a neutralizing antibody with maximal breath to avoid any viral escape, while also helping to recruit the immune system to build lasting immunity. The sequence of the ACE2-Fc protein is provided to investigators, allowing its possible use in recombinant protein expression systems to start producing drug today to treat patients under compassionate use, while formal clinical trials are later undertaken. Such a treatment could help infected patients before a protective vaccine is developed and widely available in the coming months to year(s).

Recent discovery and development of inhibitors targeting coronaviruses

Human coronaviruses (CoVs) are enveloped viruses with a positive-sense single-stranded RNA genome. Currently, six human CoVs have been reported including human coronavirus 229E (HCoV-229E), OC43 (HCoV-OC43), NL63 (HCoV-NL63), HKU1 (HCoV-HKU1), severe acute respiratory syndrome (SARS) coronavirus (SARS-CoV), and MiddleEast respiratory syndrome (MERS) coronavirus (MERS-CoV). They cause moderate to severe respiratory and intestinal infections in humans. In this review, we focus on recent advances in the research and development of small-molecule anti-human coronavirus therapies targeting different stages of the CoV life cycle.

COVID-19 Pandemic and Children: A Review

The severe respiratory disease COVID-19 (coronavirus disease 2019) was first reported in late December 2019 in Wuhan City, China. Soon thereafter, the World Health Organization (WHO) officially declared it a pandemic. The adult population is highly affected by severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2); however, infants and children are also not spared. Transmission in the pediatric population appears to be primarily from COVID-19-positive adults, largely from family contacts through droplets, direct contacts, and aerosols. There is also evidence of fecal-oral route of transmission. The incubation period of COVID-19 in children ranges from 2 to 10 days. Most children are asymptomatic. The most common symptoms amongst symptomatic children are fever and cough. Shortness of breath, sore throat, rhinorrhea, conjunctivitis, fatigue, and headache are other common symptoms. Diarrhea, vomiting, and abdominal pain are the common gastrointestinal symptoms that may be present with or without respiratory symptoms. Very few children are likely to develop severe disease.Supportive care is the mainstay of treatment. Though data are limited, antiviral therapies such as remdesivir, favipiravir, lopinavir/ritonavir, and other drugs like hydroxychloroquine/chloroquine have been used for severe COVID-19 cases, with remdesivir showing the greatest promise. A few children may develop an exaggerated immune response, characterized by exaggerated cytokine release and manifests with features similar to Kawasaki disease. The syndrome has been referred to by many names including pediatric inflammatory multisystem syndrome (PIMS) and more recently, as multisystem inflammatory syndrome in children (MIS-C); this life-threatening condition often requires a multidisciplinary team effort and use of immunomodulators.

Consensus virtual screening of dark chemical matter and food chemicals uncover potential inhibitors of SARS-CoV-2 main protease

The pandemic caused by SARS-CoV-2 (COVID-19 disease) has claimed more than 500 000 lives worldwide, and more than nine million people are infected. Unfortunately, an effective drug or vaccine for its treatment is yet to be found. The increasing information available on critical molecular targets of SARS-CoV-2 and active compounds against related coronaviruses facilitates the proposal (or repurposing) of drug candidates for the treatment of COVID-19, with the aid of in silico methods. As part of a global effort to fight the COVID-19 pandemic, herein we report a consensus virtual screening of extensive collections of food chemicals and compounds known as dark chemical matter. The rationale is to contribute to global efforts with a description of currently underexplored chemical space regions. The consensus approach included combining similarity searching with various queries and fingerprints, molecular docking with two docking protocols, and ADMETox profiling. We propose compounds commercially available for experimental testing. The full list of virtual screening hits is disclosed.

As part of a global effort to identify drug candidates for the treatment of COVID-19, herein, we report small molecules commercially available selected from a consensus virtual screening strategy.

Effects of Gene-Eden-VIR and Novirin on SARS-CoV: Implications for COVID-19

The coronavirus (SARS-CoV-2), which causes COVID-19, is a betacoronavirus closely related to the human severe acute respiratory syndrome (SARS)-coronavirus (SARS-CoV). The recent COVID-19 outbreak created an urgent need for treatment. To expedite the development of such treatment, pharmaceutical companies and government agencies are currently testing several existing drugs for their effect on the virus. Gene-Eden-VIR and Novirin are natural, broad-spectrum, antiviral treatments proven to be safe and effective in several clinical studies. In this article, we present evidence indicating that the 5 Gene-Eden-VIR/Novirin ingredients have anti-betacoronavirus, and specifically, anti-SARS-CoV effects. We consider this evidence as a first indication of the anti-coronavirus effects of Gene-Eden-VIR/Novirin. Next, we are planning to conduct a clinical study with users of the treatments to test the effects of Gene-Eden-VIR/Novirin on individuals at risk and those infected with the virus.

Therapeutics for COVID-19: established and in development

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) was first recognised in late 2019, with over 30000000 cases and over 1000000 deaths reported by the end of September 2020. SARS-CoV-2 infection is usually associated with fever, cough, coryza, dyspnoea, anosmia, headache and fatigue and may cause pneumonia and hypoxemia. An excessive/dysregulated inflammatory response may lead to lung damage including acute respiratory distress syndrome (ARDS), coagulopathy and other complications. Mortality amongst hospitalised patients is higher in those needing intensive care. In Australia over 27000 cases with 882 deaths had been reported by 30 September, most in Victoria. Two therapies have proven beneficial in treatment of hospitalised patients in expedited randomised placebo-controlled trials and are now in widespread use. Dexamethasone improved survival of those requiring respiratory support and the antiviral agent remdesivir decreased time to recovery in mild-moderate disease. Remdesivir was authorised by the Australian Therapeutic Goods Administration in July 2020. Over 200 other therapeutics are being tested for COVID-19 in more than 2000 clinical trials, and many more agents are in preclinical development. We review the evidence for some of the candidates for therapy in COVID-19.

Potential specific therapies in COVID-19

COVID-19 has grown into a global pandemic that has strained healthcare throughout the world. There is a sense of urgency in finding a cure for this deadly virus. In this study, we reviewed the empiric options used in common practice for COVID-19, based on the literature available online, with an emphasis on human experiences with these treatments on severe acute respiratory syndrome-associated coronavirus (SARS-COV-1) and other viruses. Convalescent blood products are the most promising potential treatment for use in COVID-19. The use of chloroquine or hydroxychloroquine (HCQ), remdesivir, and tocilizumab are some of the other promising potential therapies; however, they are yet to be tested in randomized clinical trials (RCTs). The use of lopinavir-ritonavir did not prove beneficial in a large RCT. The use of corticosteroids should be avoided in COVID-19 pneumonia unless used for other indications, based on the suggestion of harm in patients with SARS-COV-1 and Middle Eastern Respiratory Syndrome (MERS) infection. The reviews of this paper are available via the supplemental material section.

COVID-19 pandemic: Case studies and perspectives

As of September 9, 2020, Worldwide coronavirus disease 2019 (COVID-19) has caused 894 000 deaths with over 27.5 million confirmed cases. There is an urgent need for effective treatment. Considerable efforts have been placed on developing novel therapeutics, including antivirals and vaccines. Current management of COVID-19 is supportive, with several experimental drugs. Respiratory failure from acute respiratory distress syndrome overshadowed by severe cytokine storm appears to be the leading cause of mortality. This article has reviewed several unique case studies published from December 2019 through July 31, 2020 with the above perspectives.

Drug repurposing approach to fight COVID-19

Currently, there are no treatment options available for the deadly contagious disease, coronavirus disease 2019 (COVID-19). Drug repurposing is a process of identifying new uses for approved or investigational drugs and it is considered as a very effective strategy for drug discovery as it involves less time and cost to find a therapeutic agent in comparison to the de novo drug discovery process. The present review will focus on the repurposing efficacy of the currently used drugs against COVID-19 and their mechanisms of action, pharmacokinetics, dosing, safety, and their future perspective. Relevant articles with experimental studies conducted in-silico, in-vitro, in-vivo, clinical trials in humans, case reports, and news archives were selected for the review. Number of drugs such as remdesivir, favipiravir, ribavirin, lopinavir, ritonavir, darunavir, arbidol, chloroquine, hydroxychloroquine, tocilizumab and interferons have shown inhibitory effects against the SARS-CoV2 in-vitro as well as in clinical conditions. These drugs either act through virus-related targets such as RNA genome, polypeptide packing and uptake pathways or target host-related pathways involving angiotensin-converting enzyme-2 (ACE2) receptors and inflammatory pathways. Using the basic knowledge of viral pathogenesis and pharmacodynamics of drugs as well as using computational tools, many drugs are currently in pipeline to be repurposed. In the current scenario, repositioning of the drugs could be considered the new avenue for the treatment of COVID-19.

Predicting commercially available antiviral drugs that may act on the novel coronavirus (SARS-CoV-2) through a drug-target interaction deep learning model

The infection of a novel coronavirus found in Wuhan of China (SARS-CoV-2) is rapidly spreading, and the incidence rate is increasing worldwide. Due to the lack of effective treatment options for SARS-CoV-2, various strategies are being tested in China, including drug repurposing. In this study, we used our pre-trained deep learning-based drug-target interaction model called Molecule Transformer-Drug Target Interaction (MT-DTI) to identify commercially available drugs that could act on viral proteins of SARS-CoV-2. The result showed that atazanavir, an antiretroviral medication used to treat and prevent the human immunodeficiency virus (HIV), is the best chemical compound, showing an inhibitory potency with K_d of 94.94 nM against the SARS-CoV-2 3C-like proteinase, followed by remdesivir (113.13 nM), efavirenz (199.17 nM), ritonavir (204.05 nM), and dolutegravir (336.91 nM). Interestingly, lopinavir, ritonavir, and darunavir are all designed to target viral proteinases. However, in our prediction, they may also bind to the replication complex components of SARS-CoV-2 with an inhibitory potency with K_d  < 1000 nM. In addition, we also found that several antiviral agents, such as Kaletra (lopinavir/ritonavir), could be used for the treatment of SARS-CoV-2. Overall, we suggest that the list of antiviral drugs identified by the MT-DTI model should be considered, when establishing effective treatment strategies for SARS-CoV-2.

Diagnosis, treatment, and prevention of 2019 novel coronavirus infection in children: experts' consensus statement

Since the outbreak of 2019 novel coronavirus infection (2019-nCoV) in Wuhan City, China, by January 30, 2020, a total of 9692 confirmed cases and 15,238 suspected cases have been reported around 31 provinces or cities in China. Among the confirmed cases, 1527 were severe cases, 171 had recovered and been discharged at home, and 213 died. And among these cases, a total of 28 children aged from 1 month to 17 years have been reported in China. For standardizing prevention and management of 2019-nCoV infections in children, we called up an experts' committee to formulate this experts' consensus statement. This statement is based on the Novel Coronavirus Infection Pneumonia Diagnosis and Treatment Standards (the fourth edition) (National Health Committee) and other previous diagnosis and treatment strategies for pediatric virus infections. The present consensus statement summarizes current strategies on diagnosis, treatment, and prevention of 2019-nCoV infection in children.

Diagnosis and treatment recommendations for pediatric respiratory infection caused by the 2019 novel coronavirus

Since December 2019, an epidemic caused by novel coronavirus (2019-nCoV) infection has occurred unexpectedly in China. As of 8 pm, 31 January 2020, more than 20 pediatric cases have been reported in China. Of these cases, ten patients were identified in Zhejiang Province, with an age of onset ranging from 112 days to 17 years. Following the latest National recommendations for diagnosis and treatment of pneumonia caused by 2019-nCoV (the 4th edition) and current status of clinical practice in Zhejiang Province, recommendations for the diagnosis and treatment of respiratory infection caused by 2019-nCoV for children were drafted by the National Clinical Research Center for Child Health, the National Children's Regional Medical Center, Children's Hospital, Zhejiang University School of Medicine to further standardize the protocol for diagnosis and treatment of respiratory infection in children caused by 2019-nCoV.

Approaches for the Treatment of SARS-CoV-2 Infection: A Pharmacologic View and Literature Review

The emergence of a novel Coronavirus disease (COVID-19) inducing acute respiratory distress syndrome (ARDS) was identified in Hubei province of China in December 2019 and rapidly spread worldwide as pandemic and became a public health concern. COVID-19 disease is caused by a new virus known as SARS-CoV-2 (Severe Acute Respiratory Syndrome Coronavirus 2), which has recently offered many challenges and efforts to identify effective drugs for its prevention and treatment. Currently, there is no proven effective approach and medication against this virus. Quickly expanding clinical trials and studies on Coronavirus disease 2019 increase our knowledge regarding SARS-CoV-2 virus and introduce several potential drugs targeting virus moiety or host cell elements. Overall, 3 stages were suggested for SARS-CoV-2 infection according to the disease severity, clinical manifestations, and treatment outcomes, including mild, moderate, and severe. This review aimed to classify and summarize several medications and potential therapies according to the disease 3 stages; however, it is worth noting that no medication and therapy has been effective so far.

The protease inhibitor lopinavir, boosted with ritonavir, as treatment for COVID-19: a rapid review

BACKGROUND

The HIV protease inhibitor lopinavir, boosted with ritonavir, has been used off-label to treat COVID-19. We aimed to synthesize the clinical evidence for lopinavir/ritonavir as a treatment for COVID-19.

METHODS

We performed a rapid review by searching databases including PubMed, GoogleScholar, medRxiv, ClinicalTrials.gov and the Cochrane COVID-19 Study Register, for COVID-19 studies comparing outcomes between patients who did and did not receive lopinavir/ritonavir. The quality of evidence was assessed using the GRADE criteria.

RESULTS

We identified five completed randomized controlled trials (RCTs) and 14 retrospective cohort studies. Two large RCTs of 5,040 and 2,771 hospitalized adults with COVID-19 found no evidence that lopinavir/ritonavir influenced the primary outcome of mortality, or secondary outcomes including progression to mechanical ventilation or time to discharge. Results remained similar in all sub-group analyses including by age, gender, baseline ventilation and time since symptom onset. The three smaller RCTs (n=86-199) also found no evidence of a benefit in the primary outcomes of time to clinical improvement or time to viral clearance. The 14 observational studies included between 50 and 415 participants, and were limited by a lack of adjustment for potential confounding variables. The majority of these studies found no evidence that lopinavir/ritonavir was associated with improved mortality or other clinical outcomes, although results regarding viral clearance were mixed.

CONCLUSIONS

Good evidence from large clinical trials does not support using lopinavir/ritonavir to treat COVID-19 amongst hospitalized patients.

In silico and in vitro analysis of small molecules and natural compounds targeting the 3CL protease of feline infectious peritonitis virus

The computational search of chemical libraries has been used as a powerful tool for the rapid discovery of candidate compounds. To find small molecules with anti-feline infectious peritonitis virus (FIPV) properties, we utilized a virtual screening technique to identify the active site on the viral protease for the binding of the available natural compounds. The protease 3CL (3CL^pro) plays an important role in the replication cycle of FIPV and other viruses within the family Coronaviridae. The 15 best-ranked candidate consensus compounds, based on three docking tools, were evaluated for further assays. The protease inhibitor assay on recombinant FIPV 3CL^pro was performed to screen the inhibitory effect of the candidate compounds with IC₅₀ ranging from 6.36 ± 2.15 to 78.40 ± 2.60 μM. As determined by the cell-based assay, the compounds NSC345647, NSC87511, and NSC343256 showed better EC₅₀ values than the broad-spectrum antiviral drug ribavirin and the protease inhibitor lopinavir, under all the test conditions including pre-viral entry, post-viral entry, and prophylactic activity. The NSC87511 particularly yielded the best selective index (>4; range of SI = 13.80-22.90). These results indicated that the natural small-molecular compounds specifically targeted the 3CL^pro of FIPV and inhibited its replication. Structural modification of these compounds may generate a higher anti-viral potency for the further development of a novel therapy against FIP.

Severe Acute Respiratory Syndrome: Historical, Epidemiologic, and Clinical Features

Severe acute respiratory syndrome coronavirus (SARS-CoV), emerged from China and rapidly spread worldwide. Over 8098 people fell ill and 774 died before the epidemic ended in July 2003. Bats are likely an important reservoir for SARS-CoV. SARS-like CoVs have been detected in horseshoe bats and civet cats. The main mode of transmission of SARS-CoV is through inhalation of respiratory droplets. Faeco-oral transmission has been recorded. Strict infection control procedures with respiratory and contact precautions are essential. Fever and respiratory symptoms predominate, and diarrhea is common. Treatment involves supportive care. There are no specific antiviral treatments or vaccines available.

Computational evaluation of the reactivity and pharmaceutical potential of an organic amine: A DFT, molecular dynamics simulations and molecular docking approach

2-[N-(carboxymethyl)anilino] acetic acid (PIDAA) molecule has been spectroscopically characterized and computationally investigated for its fundamental reactive properties by a combination of density functional theory (DFT) calculations, molecular dynamics (MD) simulations and molecular docking procedure. A comparison drawn between the simulated and experimentally attained spectra by FT-Raman and FT-IR showed concurrence. The natural bond orbital (NBO) analysis enabled in comprehending the stability and charge delocalization in the title molecule. The first hyperpolarizability which is an important parameter for future studies of nonlinear optics (NLO) was calculated to check the potential of the molecule to be an NLO material. Besides, frontier molecular orbitals (FMO), electron localization function (ELF) and localized orbital locator (LOL) analysis were performed. Energy gap (ΔE), electronegativity (χ), chemical potential (μ), global hardness (η), softness (S), Mulliken population analysis on atomic charges and thermodynamic properties of the title compound at different temperatures have been calculated. The local reactive properties of PIDAA have been addressed by MEP and ALIE surfaces, together with bond dissociation energy for hydrogen abstraction (H-BDE). MD simulations have been used in order to identify atoms with pronounced interactions with water molecules. The pharmaceutical potential of PIDAA has been considered by the analysis of drug likeness parameters and molecular docking procedure. The biological activity of the molecule in terms of molecular docking has been analyzed theoretically for the treatment of SARS and minimum binding energy calculated. The Ramachandran plot was used to check the stereochemistry of the protein structure. In addition, a comparison of the physiochemical parameters of PIDAA and commercially available drugs (Yu et al., 2004; Tan et al., 2004; Elshabrawy et al., 2014; Chu et al., 2004; Gopal Samy and Xavier, 2015) were carried out.

Pharmacotherapy of Lower Respiratory Tract Infections in Elderly-Focused on Antibiotics

Lower respiratory tract infections (LRTIs) refer to the inflammation of the trachea, bronchi, bronchioles, and lung tissue. Old people have an increased risk of developing LRTIs compared to young adults. The prevalence of LRTIs in the elderly population is not only related to underlying diseases and aging itself, but also to a variety of clinical issues, such as history of hospitalization, previous antibacterial therapy, mechanical ventilation, antibiotic resistance. These factors mentioned above have led to an increase in the prevalence and mortality of LRTIs in the elderly, and new medical strategies targeting LRTIs in this population are urgently needed. After a systematic review of the current randomized controlled trials and related studies, we recommend novel pharmacotherapies that demonstrate advantages for the management of LRTIs in people over the age of 65. We also briefly reviewed current medications for respiratory communicable diseases in the elderly. Various sources of information were used to ensure all relevant studies were included. We searched Pubmed, MEDLINE (OvidSP), EMBASE (OvidSP), and ClinicalTrials.gov. Strengths and limitations of these drugs were evaluated based on whether they have novelty of mechanism, favorable pharmacokinetic/pharmacodynamic profiles, avoidance of interactions and intolerance, simplicity of dosing, and their ability to cope with challenges which was mainly evaluated by the primary and secondary endpoints. The purpose of this review is to recommend the most promising antibiotics for treatment of LRTIs in the elderly (both in hospital and in the outpatient setting) based on the existing results of clinical studies with the novel antibiotics, and to briefly review current medications for respiratory communicable diseases in the elderly, aiming to a better management of LRTIs in clinical practice.

Novel 2019-coronavirus on new year's Eve

An ongoing apocalyptic outbreak of a new virus causing pneumonia-like clusters in Wuhan city, China, has gleamed the world. The outbreak, confirmed on the New Year's Eve 2020, has known no boundaries since then. The number has surpassed that of Severe Acute Respiratory Syndrome (SARS) and Middle East respiratory syndrome (MERS), and is uninterruptedly escalating. Being an RNA virus, it has a propensity to mutate due to the low proofreading capacity of RNA-dependent RNA polymerase. Step-wise mutations have led to the gradual spillover of virus and after crossing the inter-species interface, the virus has adapted itself for a stable human-to-human transmission. The disease caused by severe acute respiratory syndrome coronavirus (CoV)-2 (SARS-CoV-2) can prove deadlier if the so-called 'super-spreading events' emerge with time. Recent research has shown the maximum homology of 99% of SARS-CoV-2 to pangolins associated coronavirus, owing to which these can serve as potential intermediate host. India is responding swiftly to the emergency situation, and the whole of the country is under lockdown since 25 March 2020, to ensure social distancing. All the international flights are padlocked and the travellers are being screened at airports and seaports via thermal sensors, and quarantine for a period of 14 days is recommended. Three hundred and forty-five patients across the country tested positive with six fatalities as of 22 March 2020. No specific anti-CoV drugs are currently available. Patients are being treated with protease drugs are inhibitors, remdesivir, chloroquine, angiotensin-converting enzyme 2 inhibitors, ivermectin, sarilumab and tocilizumab, though none of these is Food and Drug Administration approved and are undergoing trials. Preventive measures such as social distancing, quarantine, cough etiquettes, proper hand washing, cleaning and decontaminating the surfaces are the mainstay for curbing the transmission of this virus. The present review highlights the update of novel SARS-CoV-2 in context to the Indian scenario.

Advances in respiratory virus therapeutics - A meeting report from the 6th isirv Antiviral Group conference

The International Society for Influenza and other Respiratory Virus Diseases held its 6th Antiviral Group (isirv-AVG) conference in Rockville, Maryland, November 13-15, 2018. The three-day program was focused on therapeutics towards seasonal and pandemic influenza, respiratory syncytial virus, coronaviruses including MERS-CoV and SARS-CoV, human rhinovirus, and other respiratory viruses. Updates were presented on several influenza antivirals including baloxavir, CC-42344, VIS410, immunoglobulin, immune plasma, MHAA4549A, pimodivir (JNJ-63623872), umifenovir, and HA minibinders; RSV antivirals including presatovir (GS-5806), ziresovir (AK0529), lumicitabine (ALS-008176), JNJ-53718678, JNJ-64417184, and EDP-938; broad spectrum antivirals such as favipiravir, VH244, remdesivir, and EIDD-1931/EIDD-2801; and host directed strategies including nitazoxanide, eritoran, and diltiazem. Other topics included considerations of novel endpoints such as ordinal scales and patient reported outcomes (PRO), and study design issues, and other regulatory considerations for antiviral drug development. The aim of this report is to provide a summary of the presentations given at this meeting.

Broad-spectrum coronavirus antiviral drug discovery

Introduction: The highly pathogenic coronaviruses severe acute respiratory syndrome coronavirus (SARS-CoV) and Middle East respiratory syndrome coronavirus (MERS-CoV) are lethal zoonotic viruses that have emerged into human populations these past 15 years. These coronaviruses are associated with novel respiratory syndromes that spread from person-to-person via close contact, resulting in high morbidity and mortality caused by the progression to Acute Respiratory Distress Syndrome (ARDS).

Areas covered: The risks of re-emergence of SARS-CoV from bat reservoir hosts, the persistence of MERS-CoV circulation, and the potential for future emergence of novel coronaviruses indicate antiviral drug discovery will require activity against multiple coronaviruses. In this review, approaches that antagonize viral nonstructural proteins, neutralize structural proteins, or modulate essential host elements of viral infection with varying levels of efficacy in models of highly pathogenic coronavirus disease are discussed.

Expert opinion: Treatment of SARS and MERS in outbreak settings has focused on therapeutics with general antiviral activity and good safety profiles rather than efficacy data provided by cellular, rodent, or nonhuman primate models of highly pathogenic coronavirus infection. Based on lessons learned from SARS and MERS outbreaks, lack of drugs capable of pan-coronavirus antiviral activity increases the vulnerability of public health systems to a highly pathogenic coronavirus pandemic.

Decoding the enigma of antiviral crisis: Does one target molecule regulate all?

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IL-6 class switching provides regulation over pro- and anti-inflammatory responses.

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Unregulated IL-6 trans-signaling promotes uncontrolled pro-inflammatory responses.

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ADAM-17 regulates class switching between IL-6 trans- and classical-signaling.

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Selective ADAM-17 blocking restricts overexpression of pro-inflammatory cytokines.

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ADAM-17 may be an antiviral drug target to reduce immunopathology disease severity.

Disease fatality associated with Ebola, SARS-CoV and dengue infections in humans is attributed to a cytokine storm that is triggered by excessive pro-inflammatory responses. Interleukin (IL)-6 acts as a mediator between pro- and anti-inflammatory reactivity by initiating trans- and classical-signaling, respectively. Hence, IL-6 is assumed to provide a target for a broad range of antiviral agents. Available immunosuppressive antivirals are directed to control an often exaggerated pro-inflammatory response that gives rise to complex clinical conditions such as lymphocytopenia. It is known that IL-6, via its soluble receptor (sIL-6R), initiates a pro-inflammatory response while an anti-inflammatory response is triggered by the membrane-bound IL-6 receptor (IL-6R). Future antivirals should thus aim to target the mechanism that regulates switching between IL-6 trans- and classical-signaling. In this review, we propose that the tumour necrosis factor-α converting enzyme ADAM-17 could be the master molecule involved in regulating IL-6 class switching and through this in controlling pro- and anti-inflammatory responses to viral antigenic stimuli. Therefore, ADAM-17 should be considered as a potential target molecule for novel antiviral drug discovery that would regulate host reactivity to infection and thereby limit or prevent fatal outcomes.

Treatment of Middle East Respiratory Syndrome with a combination of lopinavir-ritonavir and interferon-β1b (MIRACLE trial): study protocol for a randomized controlled trial

Background

It had been more than 5 years since the first case of Middle East Respiratory Syndrome coronavirus infection (MERS-CoV) was recorded, but no specific treatment has been investigated in randomized clinical trials. Results from in vitro and animal studies suggest that a combination of lopinavir/ritonavir and interferon-β1b (IFN-β1b) may be effective against MERS-CoV. The aim of this study is to investigate the efficacy of treatment with a combination of lopinavir/ritonavir and recombinant IFN-β1b provided with standard supportive care, compared to treatment with placebo provided with standard supportive care in patients with laboratory-confirmed MERS requiring hospital admission.

Methods

The protocol is prepared in accordance with the SPIRIT (Standard Protocol Items: Recommendations for Interventional Trials) guidelines. Hospitalized adult patients with laboratory-confirmed MERS will be enrolled in this recursive, two-stage, group sequential, multicenter, placebo-controlled, double-blind randomized controlled trial. The trial is initially designed to include 2 two-stage components. The first two-stage component is designed to adjust sample size and determine futility stopping, but not efficacy stopping. The second two-stage component is designed to determine efficacy stopping and possibly readjustment of sample size. The primary outcome is 90-day mortality.

Discussion

This will be the first randomized controlled trial of a potential treatment for MERS. The study is sponsored by King Abdullah International Medical Research Center, Riyadh, Saudi Arabia. Enrollment for this study began in November 2016, and has enrolled thirteen patients as of Jan 24-2018.

Trial registration

ClinicalTrials.gov, ID: NCT02845843. Registered on 27 July 2016.

Electronic supplementary material

The online version of this article (doi:10.1186/s13063-017-2427-0) contains supplementary material, which is available to authorized users.

Middle East Respiratory Syndrome and Severe Acute Respiratory Syndrome: Current Therapeutic Options and Potential Targets for Novel Therapies

No specific antivirals are currently available for two emerging infectious diseases, Middle East respiratory syndrome (MERS) and severe acute respiratory syndrome (SARS). A literature search was performed covering pathogenesis, clinical features and therapeutics, clinically developed drugs for repurposing and novel drug targets. This review presents current knowledge on the epidemiology, pathogenesis and clinical features of the SARS and MERS coronaviruses. The rationale for and outcomes with treatments used for SARS and MERS is discussed. The main focus of the review is on drug development and the potential that drugs approved for other indications provide for repurposing. The drugs we discuss belong to a wide range of different drug classes, such as cancer therapeutics, antipsychotics, and antimalarials. In addition to their activity against MERS and SARS coronaviruses, many of these approved drugs have broad-spectrum potential and have already been in clinical use for treating other viral infections. A wealth of knowledge is available for these drugs. However, the information in this review is not meant to guide clinical decisions, and any therapeutic described here should only be used in context of a clinical trial. Potential targets for novel antivirals and antibodies are discussed as well as lessons learned from treatment development for other RNA viruses. The article concludes with a discussion of the gaps in our knowledge and areas for future research on emerging coronaviruses.

MERS, SARS and other coronaviruses as causes of pneumonia

Human coronaviruses (HCoVs) have been considered to be relatively harmless respiratory pathogens in the past. However, after the outbreak of the severe acute respiratory syndrome (SARS) and emergence of the Middle East respiratory syndrome (MERS), HCoVs have received worldwide attention as important pathogens in respiratory tract infection. This review focuses on the epidemiology, pathogenesis and clinical characteristics among SARS-coronaviruses (CoV), MERS-CoV and other HCoV infections.

Epidemic and Emerging Coronaviruses (Severe Acute Respiratory Syndrome and Middle East Respiratory Syndrome)

Bats are the natural reservoirs of severe acute respiratory syndrome (SARS)-like coronaviruses (CoVs) and likely the reservoir of Middle East respiratory syndrome (MERS)-CoV. The clinical features of SARS-CoV infection and MERS-CoV infection are similar but MERS-CoV infection progresses to respiratory failure more rapidly. Although the estimated pandemic potential of MERS-CoV is lower than that of SARS-CoV, the case fatality rate of MERS is higher. The transmission route and the possibility of other intermediary animal sources remain uncertain among many sporadic primary cases. Clinical trial options for MERS-CoV infection include monotherapy and combination therapy.

Nidovirus RNA polymerases: Complex enzymes handling exceptional RNA genomes

Coronaviruses and arteriviruses are distantly related human and animal pathogens that belong to the order Nidovirales. Nidoviruses are characterized by their polycistronic plus-stranded RNA genome, the production of subgenomic mRNAs and the conservation of a specific array of replicase domains, including key RNA-synthesizing enzymes. Coronaviruses (26-34 kilobases) have the largest known RNA genomes and their replication presumably requires a processive RNA-dependent RNA polymerase (RdRp) and enzymatic functions that suppress the consequences of the typically high error rate of viral RdRps. The arteriviruses have significantly smaller genomes and form an intriguing package with the coronaviruses to analyse viral RdRp evolution and function. The RdRp domain of nidoviruses resides in a cleavage product of the replicase polyprotein named non-structural protein (nsp) 12 in coronaviruses and nsp9 in arteriviruses. In all nidoviruses, the C-terminal RdRp domain is linked to a conserved N-terminal domain, which has been coined NiRAN (nidovirus RdRp-associated nucleotidyl transferase). Although no structural information is available, the functional characterization of the nidovirus RdRp and the larger enzyme complex of which it is part, has progressed significantly over the past decade. In coronaviruses several smaller, non-enzymatic nsps were characterized that direct RdRp function, while a 3'-to-5' exoribonuclease activity in nsp14 was implicated in fidelity. In arteriviruses, the nsp1 subunit was found to maintain the balance between genome replication and subgenomic mRNA production. Understanding RdRp behaviour and interactions during RNA synthesis and subsequent processing will be key to rationalising the evolutionary success of nidoviruses and the development of antiviral strategies.

Severe Acute Respiratory Syndrome (SARS)

Severe acute respiratory syndrome (SARS) is caused by a novel coronavirus (SARS-CoV), spread largely via droplets. Patients present with rapidly progressive pneumonia and respiratory failure. Diagnosis requires the demonstration of epidemiological linkage, clinical profiles, and virological evidence of SARS-CoV infection. Treatment of SARS is largely anecdotal. High-dose corticosteroid therapy might be useful for critically ill patients, but previous use of ribavirin (a broad-spectrum antiviral agent) was probably not efficacious. Some survivors of SARS suffer from avascular necrosis of hip and knee joints. Poor prognostic factors include advanced age, comorbidities, and high serum lactate dehydrogenase and neutrophil levels.

A review of treatment modalities for Middle East Respiratory Syndrome

The Middle East Respiratory Syndrome coronavirus (MERS-CoV) has been a focus of international attention since its identification in 2012. Epidemiologically it is characterized by sporadic community cases, which are amplified by hospital-based outbreaks. Healthcare facilities in 27 countries from most continents have experienced imported cases, with the most significant outbreak involving 186 cases in Korea. The mortality internationally is 36% and guidance for clinical management has yet to be developed. Most facilities and healthcare providers outside of the Middle East receiving patients have no or little experience in the clinical management of MERS. When a case does occur there is likely little time for a critical appraisal of the literature and putative pharmacological options. We identified published literature on the management of both MERS-CoV and the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV) through searches of PubMed and WHO and the US CDC websites up to 30 April 2016. A total of 101 publications were retrieved for critical appraisal. Most published literature on therapeutics for MERS are in vitro experiments, animal studies and case reports. Current treatment options for MERS can be categorized as: immunotherapy with virus-specific antibodies in convalescent plasma; polyclonal and monoclonal antibodies produced in vitro or in genetically modified animals; and antiviral agents. The use of any therapeutics in MERS-CoV remains investigational. The therapeutic agents with potential benefits and warranting further investigation include convalescent plasma, interferon-β/ribavirin combination therapy and lopinavir. Corticosteroids, ribavirin monotherapy and mycophenolic acid likely have toxicities that exceed potential benefits.

Update on Human Rhinovirus and Coronavirus Infections

Human rhinovirus (HRV) and coronavirus (HCoV) infections are associated with both upper respiratory tract illness (“the common cold”) and lower respiratory tract illness (pneumonia). New species of HRVs and HCoVs have been diagnosed in the past decade. More sensitive diagnostic tests such as reverse transcription-polymerase chain reaction have expanded our understanding of the role these viruses play in both immunocompetent and immunosuppressed hosts. Recent identification of severe acute respiratory syndrome and Middle East respiratory syndrome viruses causing serious respiratory illnesses has led to renewed efforts for vaccine development. The role these viruses play in patients with chronic lung disease such as asthma makes the search for antiviral agents of increased importance.

SARS and MERS: recent insights into emerging coronaviruses

The emergence of Middle East respiratory syndrome coronavirus (MERS-CoV) in 2012 marked the second introduction of a highly pathogenic coronavirus into the human population in the twenty-first century. The continuing introductions of MERS-CoV from dromedary camels, the subsequent travel-related viral spread, the unprecedented nosocomial outbreaks and the high case-fatality rates highlight the need for prophylactic and therapeutic measures. Scientific advancements since the 2002-2003 severe acute respiratory syndrome coronavirus (SARS-CoV) pandemic allowed for rapid progress in our understanding of the epidemiology and pathogenesis of MERS-CoV and the development of therapeutics. In this Review, we detail our present understanding of the transmission and pathogenesis of SARS-CoV and MERS-CoV, and discuss the current state of development of measures to combat emerging coronaviruses.

Coronaviruses - drug discovery and therapeutic options

In humans, infections with the human coronavirus (HCoV) strains HCoV-229E, HCoV-OC43, HCoV-NL63 and HCoV-HKU1 usually result in mild, self-limiting upper respiratory tract infections, such as the common cold. By contrast, the CoVs responsible for severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), which were discovered in Hong Kong, China, in 2003, and in Saudi Arabia in 2012, respectively, have received global attention over the past 12 years owing to their ability to cause community and health-care-associated outbreaks of severe infections in human populations. These two viruses pose major challenges to clinical management because there are no specific antiviral drugs available. In this Review, we summarize the epidemiology, virology, clinical features and current treatment strategies of SARS and MERS, and discuss the discovery and development of new virus-based and host-based therapeutic options for CoV infections.

Coronaviruses - drug discovery and therapeutic options

Severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS) are examples of emerging zoonotic coronavirus infections capable of person-to-person transmission that result in large-scale epidemics with substantial effects on patient health and socioeconomic factors. Unlike patients with mild illnesses that are caused by other human-pathogenic coronaviruses, patients with SARS or MERS coronavirus infections may develop severe acute respiratory disease with multi-organ failure. The case–fatality rates of SARS and MERS are approximately 10% and 35%, respectively.

Both SARS and MERS pose major clinical management challenges because there is no specific antiviral treatment that has been proven to be effective in randomized clinical trials for either infection. Substantial efforts are underway to discover new therapeutic agents for coronavirus infections.

Virus-based therapies include monoclonal antibodies and antiviral peptides that target the viral spike glycoprotein, viral enzyme inhibitors, viral nucleic acid synthesis inhibitors and inhibitors of other viral structural and accessory proteins.

Host-based therapies include agents that potentiate the interferon response or affect either host signalling pathways involved in viral replication or host factors utilized by coronaviruses for viral replication.

The major challenges in the clinical development of novel anti-coronavirus drugs include the limited number of suitable animal models for the evaluation of potential treatments for SARS and MERS, the current absence of new SARS cases, the limited number of MERS cases — which are also predominantly geographically confined to the Middle East — as well as the lack of industrial incentives to develop antivirals for mild infections caused by other, less pathogenic coronaviruses.

The continuing threat of MERS-CoV to global health 3 years after its discovery presents a golden opportunity to tackle current obstacles in the development of new anti-coronavirus drugs. A well-organized, multidisciplinary, international collaborative network consisting of clinicians, virologists and drug developers, coupled to political commitment, should be formed to carry out clinical trials using anti-coronavirus drugs that have already been shown to be safe and effective in vitro and/or in animal models, particularly lopinavir–ritonavir, interferon beta-1b and monoclonal antibodies and antiviral peptides targeting the viral spike glycoprotein.

Severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), which are caused by coronaviruses, have attracted substantial attention owing to their high mortality rates and potential to cause epidemics. Yuen and colleagues discuss progress with treatment options for these syndromes, including virus- and host-targeted drugs, and the challenges that need to be overcome in their further development.

In humans, infections with the human coronavirus (HCoV) strains HCoV-229E, HCoV-OC43, HCoV-NL63 and HCoV-HKU1 usually result in mild, self-limiting upper respiratory tract infections, such as the common cold. By contrast, the CoVs responsible for severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS), which were discovered in Hong Kong, China, in 2003, and in Saudi Arabia in 2012, respectively, have received global attention over the past 12 years owing to their ability to cause community and health-care-associated outbreaks of severe infections in human populations. These two viruses pose major challenges to clinical management because there are no specific antiviral drugs available. In this Review, we summarize the epidemiology, virology, clinical features and current treatment strategies of SARS and MERS, and discuss the discovery and development of new virus-based and host-based therapeutic options for CoV infections.

Combination therapy with lopinavir/ritonavir, ribavirin and interferon-α for Middle East respiratory syndrome

Since the first report of Middle East respiratory syndrome (MERS) in 2012 in Saudi Arabia, no standard treatment guideline has been set despite the virulence of MERS-coronavirus (CoV) and the high case-fatality rate. The outbreak in South Korea in 2015 demonstrates that MERS outbreaks can occur outside of the Middle East. The combination of ribavirin and interferon-α has been the most widely used therapy for this infection. However, due to the varying results of treatment with these drugs, a new antiviral combination regimen is urgently needed. This is a case report of use of lopinavir/ritonavir-based combination antiviral therapy for a patient with MERS-CoV infection.