Doxycycline or minocycline may be a viable treatment option against SARS-CoV-2

Minocycline as a prospective therapeutic agent for cancer and non-cancer diseases: a scoping review

Minocycline is an FDA-approved secondary-generation tetracycline antibiotic. It is a synthetic antibiotic having many biological effects, such as antioxidant, anti-inflammatory, anti-cancer, and neuroprotective functions. This study discusses the pharmacological mechanisms of preventive and therapeutic effects of minocycline. Specifically, it provides a comprehensive overview of the molecular pathways by which minocycline acts on the different cancers, including ovarian, breast, glioma, colorectal, liver, pancreatic, lung, prostate, melanoma, head and neck, leukemia, and non-cancer diseases such as Alzheimer's disease, Parkinson, schizophrenia, multiple sclerosis, Huntington, polycystic ovary syndrome, and coronavirus disease 19. Minocycline may be a potential medication for these disorders due to its strong blood-brain barrier penetrance. It is also widely accepted as a specific medication, has a well-known side-effect characteristic, is reasonably priced, making it appropriate for continuous use in managing diseases, and has been demonstrated as an oral approach because it is effectively absorbed and accomplished almost all of the body's parts.

Analysis of possible pathways on the mechanism of action of minocycline and doxycycline against strains of Candida spp. resistant to fluconazole

Species of the genus Candida, characterized as commensals of the human microbiota, are opportunistic pathogens capable of generating various types of infections with high associated costs. Considering the limited pharmacological arsenal and the emergence of antifungal-resistant strains, the repositioning of drugs is a strategy used to search for new therapeutic alternatives, in which minocycline and doxycycline have been evaluated as potential candidates. Thus, the objective was to evaluate the in vitro antifungal activity of two tetracyclines, minocycline and doxycycline, and their possible mechanism of action against fluconazole-resistant strains of Candida spp. The sensitivity test for antimicrobials was performed using the broth microdilution technique, and the pharmacological interaction with fluconazole was also analysed using the checkerboard method. To analyse the possible mechanisms of action, flow cytometry assays were performed. The minimum inhibitory concentration obtained was 4-427 µg ml-1 for minocycline and 128-512 µg ml-1 for doxycycline, and mostly indifferent and additive interactions with fluconazole were observed. These tetracyclines were found to promote cellular alterations that generated death by apoptosis, with concentration-dependent reactive oxygen species production and reduced cell viability. Therefore, minocycline and doxycycline present themselves as promising study molecules against Candida spp.

In Silico Molecular Characterization of Human TMPRSS2 Protease Polymorphic Variants and Associated SARS-CoV-2 Susceptibility

The 2019 coronavirus disease (COVID-19) pandemic continues to challenge health care systems worldwide. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has been responsible for the cause of global pandemic. Type 2 transmembrane serine protease (TMPRSS2) is important in the cell entry and spread of SARS-CoV-2 and plays a crucial role in the proteolytic cleavage of SARS-CoV-2 spike (S) glycoprotein. Here, using reported structural data, we analyzed the molecular complex of TMPRSS2 and the S glycoprotein and further examined intermolecular interactions of natural TMPRSS2 polymorphic variants. We identified several TMPRSS2 variants that could possibly alter host susceptibility to the SARS-CoV-2 infection. Molecular docking analysis revealed that G462D/G462S variants were predicted to be protective variants, whereas Q438E and S339F variants were predicted to increase susceptibility. In addition, we examined intermolecular interactions between TMPRSS2 and its two potential serine protease inhibitors, camostat mesylate and nafamostat. Further, we investigated the effect of TMPRSS2 variants on these interactions. Our structural analysis revealed that G462D, C297S and S460R variants had possibly altered the interactions with the protease inhibitors. Our results identified important TMPRSS2 variations that could be useful to develop high affinity and personalized drugs for treating COVID-19 patients.

Races of small molecule clinical trials for the treatment of COVID-19: An up-to-date comprehensive review

The coronavirus disease‐19 (COVID‐19) pandemic has become a global threat since its first outbreak at the end of 2019. Several review articles have been published recently, focusing on the aspects of target biology, drug repurposing, and mechanisms of action (MOAs) for potential treatment. This review gathers all small molecules currently in active clinical trials, categorizes them into six sub‐classes, and summarizes their clinical progress. The aim is to provide the researchers from both pharmaceutical industries and academic institutes with the handful information and dataset to accelerate their research programs in searching effective small molecule therapy for treatment of COVID‐19.

Integrating heterogeneous data to facilitate COVID-19 drug repurposing

In the COVID-19 pandemic, drug repositioning has presented itself as an alternative to the time-consuming process of generating new drugs. This review describes a drug repurposing process that is based on a new data-driven approach: we put forward five information paths that associate COVID-19-related genes and COVID-19 symptoms with drugs that directly target these gene products, that target the symptoms or that treat diseases that are symptomatically or genetically similar to COVID-19. The intersection of the five information paths results in a list of 13 drugs that we suggest as potential candidates against COVID-19. In addition, we have found information in published studies and in clinical trials that support the therapeutic potential of the drugs in our final list.

A network representation approach for COVID-19 drug recommendation

The coronavirus disease 2019 (COVID-19) has outbreak since early December 2019, and COVID-19 has caused over 100 million cases and 2 million deaths around the world. After one year of the COVID-19 outbreak, there is no certain and approve medicine against it. Drug repositioning has become one line of scientific research that is being pursued to develop an effective drug. However, due to the lack of COVID-19 data, there is still no specific drug repositioning targeting the COVID-19. In this paper, we propose a framework for COVID-19 drug repositioning. This framework has several advantages that can be exploited: one is that a local graph aggregating representation is used across a heterogeneous network to address the data sparsity problem; another is the multi-hop neighbors of the heterogeneous graph are aggregated to recall as many COVID-19 potential drugs as possible. Our experimental results show that our COVDR framework performs significantly better than baseline methods, and the docking simulation verifies that our three potential drugs have the ability to against COVID-19 disease.

Doxycycline Inhibition of a Pseudotyped Virus Transduction Does Not Translate to Inhibition of SARS-CoV-2 Infectivity

The rapid spread of the pandemic caused by the SARS-CoV-2 virus has created an unusual situation, with rapid searches for compounds to interfere with the biological processes exploited by the virus. Doxycycline, with its pleiotropic effects, including anti-viral activity, has been proposed as a therapeutic candidate for COVID-19 and about twenty clinical trials have started since the beginning of the pandemic. To gain information on the activity of doxycycline against SARS-CoV-2 infection and clarify some of the conflicting clinical data published, we designed in vitro binding tests and infection studies with a pseudotyped virus expressing the spike protein, as well as a clinically isolated SARS-CoV-2 strain. Doxycycline inhibited the transduction of the pseudotyped virus in Vero E6 and HEK-293 T cells stably expressing human receptor angiotensin-converting enzyme 2 but did not affect the entry and replication of SARS-CoV-2. Although this conclusion is apparently disappointing, it is paradigmatic of an experimental approach aimed at developing an integrated multidisciplinary platform which can shed light on the mechanisms of action of potential anti-COVID-19 compounds. To avoid wasting precious time and resources, we believe very stringent experimental criteria are needed in the preclinical phase, including infectivity studies with clinically isolated SARS-CoV-2, before moving on to (futile) clinical trials.

Sequential doxycycline and colchicine combination therapy in Covid-19: The salutary effects

Coronavirus virus disease 2019 (COVID-19) is a viral infectious disease caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), actually considered as a global pandemic. The entry-point for SARS-CoV-2 is angiotensin converting enzyme 2 (ACE2) and dipeptidyl peptidase 4 (DPP4), which are highly expressed in the lung. Among other complications, COVID-19leads to fatal pneumonia, acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) due to development of cytokine storm (CS). The pathogenesis of SARS-CoV-2 infection depends on the viral load and human innate/adaptive immune response that are required for viral elimination in the first phase of COVID-19. However, an exaggerated immune response in the second phase of COVID-19 results in immune overreaction and CS-induced ALI and ARDS. Thus, in view of these considerations, we report here a series of five patients with COVID-19 pneumonia who developed ALI. In addition to the supportive therapy, the patients received doxycycline in the first week and doxycycline plus colchicine in the second week. Following sequential therapy with doxycycline and/or colchicine in patients with COVID-19 pneumonia, the patients had reduction of disease severity and symptoms with better clinical and radiological outcomes. However, it is tough to confirm the link between this therapeutic combination and recovery from COVID-19 pneumonia, as it is a small case-series report. Nevertheless, this study gives a rational for large-scale prospective studies to evaluate the dual sequential effect of doxycycline and colchicine on the COVID-19 severity. This case-series illustrated that use of colchicine: doxycycline combination is linked with marked improvements in the clinical, laboratory and radiological outcomes in patients with COVID-19 pneumonia. However, we cannot sketch any definitive conclusion from our observation, despite we hypothesize that this combination therapeutic regimen may attenuate and treat COVID-19. Further, namely prospective, randomized, and controlled clinical studies are recommended in this regard.

The situation of small molecules targeting key proteins to combat SARS-CoV-2: Synthesis, metabolic pathway, mechanism of action, and potential therapeutic applications

Due to the global epidemic and high mortality of 2019 coronavirus disease (COVID-19), there is an immediate need to discover drugs that can help before a vaccine becomes available. Given that the process of producing new drugs is so long, the strategy of repurposing existing drugs is one of the promising options for the urgent treatment of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes COVID-19 disease. Although FDA has approved Remdesivir for the use in hospitalized adults and pediatric patients suffering from COVID-19, no fully effective and reliable drug has been yet identified worldwide to treat COVID-19 specifically. Thus, scientists are still trying to find antivirals specific to COVID-19. This work reviews the chemical structure, metabolic pathway, mechanism of action of existing drugs with potential therapeutic applications for COVID-19. Further, we summarized the molecular docking stimulation of the medications related to key protein targets. These already drugs could be developed for further clinical trials to supply suitable therapeutic options for patients suffering from COVID-19.

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

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

Repurposing therapeutic agents against SARS-CoV-2 infection: most promising and neoteric progress

INTRODUCTION

The pathogenic and highly transmissible etiological agent, SARS-CoV-2, has caused a serious threat COVID-19 pandemic. WHO has declared the epidemic a public health emergency of international concern owing to its high contagiosity, mortality rate, and morbidity. Till now, there is no approved vaccine or drug to combat the COVID-19 and avert this global crisis.

AREAS COVERED

In this narrative review, we summarized the updated results (January to August 2020) of the most promising repurposing therapeutic candidates to treat the SARS-CoV-2 viral infection. The repurposed drugs classified under four headlines like antivirals, anti-parasitic, immune-modulating, and miscellaneous drugs were discussed with their in vitro efficacy to recent clinical advancements against COVID-19.

EXPERT OPINION

Currently, palliative care, ranging from outpatient management to intensive care, including oxygen administration, ventilator support, intravenous fluids therapy, with some repurposed drugs, are the primary weapons to fight against COVID-19. Until a safe and effective vaccine is developed, an evidence-based drug repurposing strategy might be the wisest option to save people from this catastrophe. Several existing drugs are now under clinical trials, and some of them are approved in different places of the world for emergency use or as adjuvant therapy in COVID-19 with standard of care.