scholarly journals Repurposing Therapeutics for Potential Treatment of SARS-CoV-2: A Review

Viruses ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 705 ◽  
Author(s):  
Jennifer Santos ◽  
Stephanie Brierley ◽  
Mohit J. Gandhi ◽  
Michael A. Cohen ◽  
Phillip C. Moschella ◽  
...  

The need for proven disease-specific treatments for the novel pandemic coronavirus SARS-CoV-2 necessitates a worldwide search for therapeutic options. Since the SARS-CoV-2 virus shares extensive homology with SARS-CoV and MERS-CoV, effective therapies for SARS-CoV and MERS-CoV may also have therapeutic potential for the current COVID-19 outbreak. To identify therapeutics that might be repositioned for treatment of the SARS-CoV-2 disease COVID-19, we strategically reviewed the literature to identify existing therapeutics with evidence of efficacy for the treatment of the three coronaviruses that cause severe respiratory illness (SARS-CoV, MERS-CoV, and SARS-CoV-2). Mechanistic and in vitro analyses suggest multiple promising therapeutic options with potential for repurposing to treat patients with COVID-19. Therapeutics with particularly high potential efficacy for repurposing include camostat mesylate, remdesivir, favipiravir, tocilizumab, baricitinib, convalescent plasma, and humanized monoclonal antibodies. Camostat mesylate has shown therapeutic potential, likely by preventing viral entry into epithelial cells. In early research, the targeted antivirals remdesivir and favipiravir appear to benefit patients by decreasing viral replication; clinical trials suggest that remdesivir speeds recovery from COVID-19. Tocilizumab and baricitinib appear to improve mortality by preventing a severe cytokine storm. Convalescent plasma and humanized monoclonal antibodies offer passive immunity and decreased recovery time. This review highlights potential therapeutic options that may be repurposed to treat COVID-19 and suggests opportunities for further research.

2008 ◽  
Vol 82 (14) ◽  
pp. 7009-7021 ◽  
Author(s):  
Ana P. Goncalvez ◽  
Cheng-Hsin Chien ◽  
Kamolchanok Tubthong ◽  
Inna Gorshkova ◽  
Carrie Roll ◽  
...  

ABSTRACT Japanese encephalitis virus (JEV)-specific Fab antibodies were recovered by repertoire cloning from chimpanzees initially immunized with inactivated JE-VAX and then boosted with attenuated JEV SA14-14-2. From a panel of 11 Fabs recovered by different panning strategies, three highly potent neutralizing antibodies, termed Fabs A3, B2, and E3, which recognized spatially separated regions on the virion, were identified. These antibodies reacted with epitopes in different domains: the major determinant for Fab A3 was Lys179 (domain I), that for Fab B2 was Ile126 (domain II), and that for Fab E3 was Gly302 (domain III) in the envelope protein, suggesting that these antibodies neutralize the virus by different mechanisms. Potent neutralizing antibodies reacted with a low number of binding sites available on the virion. These three Fabs and derived humanized monoclonal antibodies (MAbs) exhibited high neutralizing activities against a broad spectrum of JEV genotype strains. Demonstration of antibody-mediated protection of JEV infection in vivo is provided using the mouse encephalitis model. MAb B2 was most potent, with a 50% protective dose (ED50) of 0.84 μg, followed by MAb A3 (ED50 of 5.8 μg) and then MAb E3 (ED50 of 24.7 μg) for a 4-week-old mouse. Administration of 200 μg/mouse of MAb B2 1 day after otherwise lethal JEV infection protected 50% of mice and significantly prolonged the average survival time compared to that of mice in the unprotected group, suggesting a therapeutic potential for use of MAb B2 in humans.


Author(s):  
Beverly Murray ◽  
Cindy Wolfe ◽  
Andrea Marra ◽  
Chris Pillar ◽  
Dean Shinabarger

Abstract Background Ibezapolstat (ACX-362E) is the first DNA polymerase IIIC inhibitor undergoing clinical development for the oral treatment of Clostridioides difficile infection (CDI). Methods In this study, the in vitro activity of ibezapolstat was evaluated against a panel of 104 isolates of C. difficile, including those with characterized ribotypes (e.g. 027 and 078) and those producing toxin A or B and was shown to have similar activity to those of comparators against these strains. Results The overall MIC50/90 (mg/L) for ibezapolstat against evaluated C. difficile was 2/4, compared with 0.5/4 for metronidazole, 1/4 for vancomycin and 0.5/2 for fidaxomicin. In addition, the bactericidal activity of ibezapolstat was evaluated against actively growing C. difficile by determining the MBC against three C. difficile isolates. Time–kill kinetic assays were additionally performed against the three C. difficile isolates, with metronidazole and vancomycin as comparators. Conclusions The killing of C. difficile by ibezapolstat was observed to occur at concentrations similar to its MIC, as demonstrated by MBC:MIC ratios and reflected in time–kill kinetic assays. This activity highlights the therapeutic potential of ibezapolstat for the treatment of CDI.


2009 ◽  
Vol 2009 ◽  
pp. 1-10 ◽  
Author(s):  
Helenia Ansuini ◽  
Annalisa Meola ◽  
Zeynep Gunes ◽  
Valentina Paradisi ◽  
Monica Pezzanera ◽  
...  

The EphA2 receptor tyrosine kinase is overexpressed in a variety of human epithelial cancers and is a determinant of malignant cellular behavior in pancreatic adenocarcinoma cells. Moreover, it is expressed in tumor endothelium and its activation promotes angiogenesis. To better clarify the therapeutic potential of monoclonal antibodies (mAbs) directed to the EphA2 receptor, we generated a large number of mAbs by differential screening of phage-Ab libraries by oligonucleotide microarray technology and implemented a strategy for the rapid identification of antibodies with the desired properties. We selected two high-affinity and highly specific EphA2 monoclonal antibodies with different in vitro properties on the human pancreatic tumor cell line MiaPaCa2. One is a potent EphA2-agonistic antibody, IgG25, that promotes receptor endocytosis and subsequent degradation, and the second is a ligand antagonist, IgG28, that blocks the binding to ephrin A1 and is cross-reactive with the mouse EphA2 receptor. We measured the effect of antibody treatment on the growth of MiaPaCa2 cells orthotopically transplanted in nude mice. Both IgG25 and IgG28 had strong antitumor and antimetastatic efficacy. In vivo treatment with IgG25 determined the reduction of the EphA2 protein levels in the tumor and the phosphorylation of FAK on Tyr576 while administration of IgG28 caused a decrease in tumor vascularization as measured by immunohistochemical analysis of CD31 in tumor sections. These data show that in a pancreatic cancer model comparable therapeutic efficacy is obtained either by promoting receptor degradation or by blocking receptor activation.


2021 ◽  
Vol 8 ◽  
Author(s):  
M. Ramesh ◽  
Krishnan Anand ◽  
Mohd Shahbaaz ◽  
Magda H. Abdellattif

A rapid and increasing spread of COVID-19 pandemic disease has been perceived worldwide in 2020. The current COVID-19 disease outbreak is due to the spread of SARS-CoV-2. SARS-CoV-2 is a new strain of coronavirus that has spike protein on the envelope. The spike protein of the virus binds with the ACE-2 receptor of the human lungs surface for entering into the host. Therefore, the blocking of viral entry into the host by targeting the spike protein has been suggested to be a valid strategy to treat COVID-19. The patients of COVID-19 were found to be asymptomatic, cold, mild to severe respiratory illness, and leading to death. The severe illness has been noted mainly in old age people, cardiovascular disease patients, and respiratory disease patients. However, the long-term health effects due to COVID-19 are not yet known. Recently, the vaccines were authorized to protect from COVID-19. However, the researchers have put an effort to discover suitable targets and newer medications in the form of small molecules or peptides, based on in-silico methods and synthetic approaches. This manuscript describes the current perspectives of the causative agent, diagnostic procedure, therapeutic targets, treatment, clinical trials, and development of potential clinical candidates of COVID-19. The study will be useful to identify the potential newer medications for the treatment of COVID-19.


2021 ◽  
Author(s):  
Amruta Narayanappa ◽  
Elizabeth B Engler-Chiurazzi ◽  
Isabel C Murray-Brown ◽  
Timothy E Gressett ◽  
Ifechukwude J Biose ◽  
...  

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is an infectious disease that has spread worldwide. Current treatments are limited in both availability and efficacy, such that improving our understanding of the factors that facilitate infection is urgently needed to more effectively treat infected individuals and to curb the pandemic. We and others have previously demonstrated the significance of interactions between the SARS-CoV-2 spike protein, integrin alpha5beta1 and human ACE2 to facilitate viral entry into host cells in vitro. We previously found that inhibition of integrin alpha5beta1 by the clinically validated small peptide ATN-161 inhibits these spike protein interactions and cell infection in vitro. In continuation with our previous findings, here we have further evaluated the therapeutic potential of ATN-161 on SARS-CoV-2 infection in k18-hACE2 transgenic (SARS-CoV-2 susceptible) mice in vivo. We discovered that treatment with single- or repeated intravenous doses of ATN-161 (1 mg/kg) within 48 hours after intranasal inoculation with SARS-CoV-2 lead to a reduction of lung viral load, viral immunofluorescence and improved lung histology in a majority of mice 72 hours post-infection. Furthermore, ATN-161 reduced SARS-CoV-2-induced increased expression of lung integrin alpha 5 and alpha v (an alpha 5-related integrin that has also been implicated in SARS-CoV-2 interactions) as well as the C-X-C motif chemokine ligand 10 (Cxcl10), further supporting the potential involvement of these integrins, and the anti-inflammatory potential of ATN-161, respectively, in SARS-CoV-2 infection. To the best of our knowledge, this is the first study demonstrating the potential therapeutic efficacy of targeting integrin alpha5beta1 in SARS-CoV-2 infection in vivo and supports the development of ATN-161 as a novel SARS-CoV-2 therapy.


Author(s):  
Neil Scolding

The extraordinary expansion in the field of neuroimmunology witnessed in the last decade is not just in the number of neurological disorders now considered to have an immune basis, nor the depth of understanding of disorders long known to be ‘neuroimmune’. Nor is it in the number of antibodies discovered and now testable, nor in the range of new immune suppressant or modifying treatments now emerging or already available. It is of course all of these things, but it is also more than the sum of these parts. What we are currently privileged to witness is the coming together of immunological understanding, the neurobiology of disease, and rational immune therapy, or at least the beginning of this process. To take one isolated example, neurogenetics and neurophysiology taught us about the clinical consequences of channel disruption; laboratory-based neuroimmunology showed antibodies to be capable of producing comparable acquired disease; and it seems likely that specific anti-B-cell humanized monoclonal antibodies offer the therapeutic potential to remove these channel-disrupting antibodies. Neither of these steps could be described in the last edition, and one can imagine similar dramatic changes will emerge before the next.


2020 ◽  
Vol 2 (2) ◽  
pp. 110-123
Author(s):  
Kulvinder Kochar Kaur ◽  
◽  
Gautam Allahbadia ◽  
Mandeep Singh ◽  
◽  
...  

Since the outbreak of the novel Coronavirus in December 2019 in Wuhan China, this novel Coronavirus disease(COVID-19) has spread worldwide taking not only epidemic proportions but with its rapid spread world health organization(WHO) was forced to declare it as a pandemic. The Severe Acute respiratory syndrome (SARS)-Coronavirus (CoV2) virus is responsible for clusters of severe respiratory illness that simulates acute respiratory syndrome that was what was initially. It is thought although that it is equivalent to the high altitude pulmonary oedema (HAPE), showing glass ground opacities in lungs. More experience is getting acquired with changes in treatment approaches from PEEP to avoid intubation and just ensure oxygen levels maintained. Human to human transmission through droplets, contaminated hands as well as surfaces, has been revealed with an incubation period varying from 2-14 days. Early diagnosis using reverse transcription polymerase chain reaction (RT-PCR) or computed tomography (CT) scan chest, quarantine, as well as supportive treatment are necessary for getting a cure. In this review we have tried to analyze the epidemiology, diagnosis, isolation, and treatment, including antiviral drugs like remdesivir, favipiravir, chloroquine and hydroxychloroquine, corticosteroids, antibiotics, and ivermectin. With 3 successful cases of convalescent plasma achieved in USA, trials going on in India along with vaccines are also detailed in this article.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Mihkel Örd ◽  
Ilona Faustova ◽  
Mart Loog

Abstract The Spike protein of the novel coronavirus SARS-CoV2 contains an insertion 680SPRRAR↓SV687 forming a cleavage motif RxxR for furin-like enzymes at the boundary of S1/S2 subunits. Cleavage at S1/S2 is important for efficient viral entry into target cells. The insertion is absent in other CoV-s of the same clade, including SARS-CoV1 that caused the 2003 outbreak. However, an analogous cleavage motif was present at S1/S2 of the Spike protein of the more distant Middle East Respiratory Syndrome coronavirus MERS-CoV. We show that a crucial third arginine at the left middle position, comprising a motif RRxR is required for furin recognition in vitro, while the general motif RxxR in common with MERS-CoV is not sufficient for cleavage. Further, we describe a surprising finding that the two serines at the edges of the insert SPRRAR↓SV can be efficiently phosphorylated by proline-directed and basophilic protein kinases. Both phosphorylations switch off furin’s ability to cleave the site. Although phospho-regulation of secreted proteins is still poorly understood, further studies, supported by a recent report of ten in vivo phosphorylated sites in the Spike protein of SARS-CoV2, could potentially uncover important novel regulatory mechanisms for SARS-CoV2.


Author(s):  
Alexandra Schäfer ◽  
Frauke Muecksch ◽  
Julio C. C. Lorenzi ◽  
Sarah R. Leist ◽  
Melissa Cipolla ◽  
...  

AbstractSARS-CoV-2, the causative agent of COVID-19, is responsible for over 24 million infections and 800,000 deaths since its emergence in December 2019. There are few therapeutic options and no approved vaccines. Here we examine the properties of highly potent human monoclonal antibodies (hu-mAbs) in a mouse adapted model of SARS-CoV-2 infection (SARS-CoV-2 MA). In vitro antibody neutralization potency did not uniformly correlate with in vivo activity, and some hu-mAbs were more potent in combination in vivo. Analysis of antibody Fc regions revealed that binding to activating Fc receptors is essential for optimal protection against SARS-CoV-2 MA. The data indicate that hu-mAb protective activity is dependent on intact effector function and that in vivo testing is required to establish optimal hu-mAb combinations for COVID-19 prevention.


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