Vaccines and Drug Therapeutics to Lock Down Novel Coronavirus Disease 2019 (COVID-19): A Systematic Review of Clinical Trials

Clinical Trials of Mesenchymal Stem Cells for the Treatment of COVID 19

Mesenchymal Stem Cells (MSCs) are being investigated as a treatment for a novel viral disease owing to their immunomodulatory, anti-inflammatory, tissue repair and regeneration characteristics, however, the exact processes are unknown. MSC therapy was found to be effective in lowering immune system overactivation and increasing endogenous healing after SARS-CoV-2 infection by improving the pulmonary microenvironment. Many studies on mesenchymal stem cells have been undertaken concurrently, and we may help speed up the effectiveness of these studies by collecting and statistically analyzing data from them. Based on clinical trial information found on clinicaltrials. gov and on 16 November 2020, which includes 63 clinical trials in the field of patient treatment with COVID-19 using MSCs, according to the trend of increasing studies in this field, and with the help of meta-analysis studies, it is possible to hope that the promise of MSCs will one day be realized. The potential therapeutic applications of MSCs for COVID-19 are investigated in this study.

Potential treatments of COVID-19: Drug repurposing and therapeutic interventions

The coronavirus disease 2019 (COVID-19) is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The infection is caused when Spike-protein (S-protein) present on the surface of SARS-CoV-2 interacts with human cell surface receptor, Angiotensin-converting enzyme 2 (ACE2). This binding facilitates SARS-CoV-2 genome entry into the human cells, which in turn causes infection. Since the beginning of the pandemic, many different therapies have been developed to combat COVID-19, including treatment and prevention. This review is focused on the currently adapted and certain other potential therapies for COVID-19 treatment, which include drug repurposing, vaccines and drug-free therapies. The efficacy of various treatment options is constantly being tested through clinical trials and in vivo studies before they are made medically available to the public.

COVID-19 in the Asia Pacific: Impact on climate change, allergic diseases and One Health

Climate change and environmental factors such as air pollution and loss of biodiversity are known to have a major impact not only on allergic diseases but also on many noncommunicable diseases. Coronavirus disease 2019 (COVID-19) resulted in many environmental changes during the different phases of the pandemic. The use of face masks, enhanced hand hygiene with hand rubs and sanitizers, use of personal protective equipment (gowns and gloves), and safe-distancing measures, reduced the overall incidence of respiratory infections and other communicable diseases. Lockdowns and border closures resulted in a significant reduction in vehicular traffic and hence environmental air pollution. Paradoxically, the use of personal protective equipment and disposables contributed to an increase in environmental waste disposal and new problems such as occupational dermatoses, especially among healthcare workers. Environmental changes and climate change over time may impact the exposome, genome, and microbiome, with the potential for short- and long-term effects on the incidence and prevalence of the allergic disease. The constant use and access to mobile digital devices and technology disrupt work-life harmony and mental well-being. The complex interactions between the environment, genetics, immune, and neuroendocrine systems may have short- and long-term impact on the risk and development of allergic and immunologic diseases in the future.

An overview of current drugs and prophylactic vaccines for coronavirus disease 2019 (COVID-19)

Designing and producing an effective vaccine is the best possible way to reduce the burden and spread of a disease. During the coronavirus disease 2019 (COVID-19) pandemic, many large pharmaceutical and biotechnology companies invested a great deal of time and money in trying to control and combat the disease. In this regard, due to the urgent need, many vaccines are now available earlier than scheduled. Based on their manufacturing technology, the vaccines available for COVID-19 (severe acute respiratory syndrome coronavirus 2 (SAR-CoV2)) infection can be classified into four platforms: RNA vaccines, adenovirus vector vaccines, subunit (protein-based) vaccines, and inactivated virus vaccines. Moreover, various drugs have been deemed to negatively affect the progression of the infection via various actions. However, adaptive variants of the SARS-CoV-2 genome can alter the pathogenic potential of the virus and increase the difficulty of both drug and vaccine development. In this review, along with drugs used in COVID-19 treatment, currently authorized COVID-19 vaccines as well as variants of the virus are described and evaluated, considering all platforms.

A Comprehensive Investigation Regarding the Differentiation of the Procurable COVID-19 Vaccines

COVID-19 caused by coronavirus SARS-CoV-2 became a serious threat to humankind for the past couple of years. The development of vaccine and its immediate application might be the only to escape from the grasp of this demoniac pandemic. Approximately 343 clinical trials on COVID-19 vaccines are ongoing currently, and almost all countries are motivating ongoing researches at warp speed for the development of vaccines against COVID-19. This review explores the progress in the development of the vaccines, their current status of ongoing clinical research, mechanisms, and regulatory approvals. Many pharmaceutical companies are already in the endgame for manufacturing various vaccines of which some are already being marketed across the globe, while others are yet to get approval for marketing. The primary aim of this review is to compare regulatory accepted vaccines in terms of their composition, doses, regulatory status, and efficacy. The study is conducted by grouping into approved and unapproved vaccines for marketing. Different routes of administration of vaccines along with the efficacy of the routes are also presented in the review. A wide range of database and clinical trial data is reviewed for sorting out the information on different vaccines. Unfortunately, many mutations (alpha, beta, gamma, delta, kappa, omicron etc.) of SARS-CoV-2 have attacked people in very short time, which is the great challenge for investigational vaccines. Moreover, some vaccines like Pfizer's BNT162, Oxford's ChAdOx1, Moderna's mRNA-1273, and Bharat Biotech's Covaxin have got regulatory approval in some countries for its distribution which may prove to stand tall against the pandemic.

COVID-19 phase 4 vaccine candidates, effectiveness on SARS-CoV-2 variants, neutralizing antibody, rare side effects, traditional and nano-based vaccine platforms: a review

The COVID-19 pandemic has endangered world health and the economy. As the number of cases is increasing, different companies have started developing potential vaccines using both traditional and nano-based platforms to overcome the pandemic. Several countries have approved a few vaccine candidates for emergency use authorization (EUA), showing significant effectiveness and inducing a robust immune response. Oxford-AstraZeneca, Pfizer-BioNTech's BNT162, Moderna's mRNA-1273, Sinovac's CoronaVac, Johnson & Johnson, Sputnik-V, and Sinopharm's vaccine candidates are leading the race. However, the SARS-CoV-2 is constantly mutating, making the vaccines less effective, possibly by escaping immune response for some variants. Besides, some EUA vaccines have been reported to induce rare side effects such as blood clots, cardiac injury, anaphylaxis, and some neurological effects. Although the COVID-19 vaccine candidates promise to overcome the pandemic, a more significant and clear understanding is needed. In this review, we brief about the clinical trial of some leading candidates, their effectiveness, and their neutralizing effect on SARS-CoV-2 variants. Further, we have discussed the rare side effects, different traditional and nano-based platforms to understand the scope of future development.

Is there impact of the SARS-CoV-2 pandemic on steroidogenesis and fertility?

In December of 2019, several cases of unknown atypical respiratory diseases emerged in Wuhan, Hubei Province in China. After preliminary research, it was stated that the disease is transmittable between humans and was named COVID-19. Over the course of next months, it spread all over the world by air and sea transport and caused a global pandemic which affects life of everyone now-a-days. A large number of countries, have since been forced to take precautions such as curfews, lockdowns, wearing facemasks etc. Even with vaccines being produced in mass numbers, lack of targeted therapy continues to be a major problem. According to studies so far it seems that elderly people are more vulnerable to severe symptoms while children tend to by asymptomatic or have milder form the disease. In our review, we focused on gathering data about the virus itself, its characteristics, paths of transmission, and its effect on hormone production and secretion. In such, there is insufficient information in the literature worldwide, especially the ones that focus on the effect of COVID-19 on individual organs systems within the human body. Hence, the present evidence-based study focused on the possible effects of COVID-19 on adrenal gland and gonads i.e. on the process of steroidogenesis and fertility.

Delivery of Nitric Oxide in the Cardiovascular System: Implications for Clinical Diagnosis and Therapy

Nitric oxide (NO) is a key molecule in cardiovascular homeostasis and its abnormal delivery is highly associated with the occurrence and development of cardiovascular disease (CVD). The assessment and manipulation of NO delivery is crucial to the diagnosis and therapy of CVD, such as endothelial dysfunction, atherosclerotic progression, pulmonary hypertension, and cardiovascular manifestations of coronavirus (COVID-19). However, due to the low concentration and fast reaction characteristics of NO in the cardiovascular system, clinical applications centered on NO delivery are challenging. In this tutorial review, we first summarized the methods to estimate the in vivo NO delivery process, based on computational modeling and flow-mediated dilation, to assess endothelial function and vulnerability of atherosclerotic plaque. Then, emerging bioimaging technologies that have the potential to experimentally measure arterial NO concentration were discussed, including Raman spectroscopy and electrochemical sensors. In addition to diagnostic methods, therapies aimed at controlling NO delivery to regulate CVD were reviewed, including the NO release platform to treat endothelial dysfunction and atherosclerosis and inhaled NO therapy to treat pulmonary hypertension and COVID-19. Two potential methods to improve the effectiveness of existing NO therapy were also discussed, including the combination of NO release platform and computational modeling, and stem cell therapy, which currently remains at the laboratory stage but has clinical potential for the treatment of CVD.

The effect of influenza vaccine on severity of COVID-19 infection: An original study from Iran

Background: The COVID-19 infection is a novel virus that mainly targets the respiratory system via specific receptors without any coronavirus-targeted therapies. Many efforts have been made to prepare specific vaccines for COVID-19 or use of prefabricated vaccines of other similar viruses, especially severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and influenza (flu). We aimed to evaluate the effects of previous flu vaccine injection on severity of incoming COVID-19 infection. Methods: We conducted a large cross-sectional study of 529 hospitalized Iranian COVID patients to evaluate the severity of disease courses in patients with or without previous flu vaccination history using some main factors like length of hospitalization, need for the intensive care unit (ICU) admission and length of stay in the ICU for comparison between COVID-19 infected patients with or without flu vaccination history. For the quantitative data, we used independent-samples t and Mann-Whitney tests. The qualitative data were calculated using the Fisher exact and chi-square tests in IBM SPSS Statistics version 22 (SPSS Inc) and P value <0.05 was considered statistically significant. Results: There were no significant differences in the demographic data of patients, disease, and severity-related parameters between the 2 groups. It means that there were not any significant differences between patients with and without history of flu vaccination regarding mean days of hospitalization, percentage of needing to be admitted to the ICU, days being admitted to the ICU (8.44±6.36 vs 7.94±8.57; 17% vs 11.5%; and 1.17±3.09 vs 0.92±3.04, retrospectively) (p=0.883, 0.235, and 0.809, respectively). In the laboratory tests, in comparison between patients with and without history of previous flu vaccination, only lymphocytes count in the vaccine positive group was higher than the vaccine negative group (20.82±11.23 vs 18.04±9.71) (p=0.067) and creatine phosphokinase (CPK) levels were higher in the vaccine negative group (146.57±109.72 vs 214.15±332.06) (p=0.006). Conclusion: We did not find any association between flu vaccination and decrease in disease severity in our patients. It seems that patients with previous history of flu vaccination may experience less laboratory abnormalities in some parameters that could be interpreted in favor of lower overall inflammation; however, this study cannot answer this definitely because of its design. As we collected retrospective data from only alive discharged patients and had no healthy control group, we could not discuss the probable effect of the vaccine on the mortality rate or its probable protective role against the infection. We need more well-designed controlled studies with different populations in different geographic areas to address the controversies.

Reporting and methodological quality of COVID-19 systematic reviews needs to be improved: an evidence mapping

OBJECTIVES

To assess the reporting and methodological quality of COVID-19 systematic reviews, and to analyze trends and gaps in the quality, clinical topics, author countries, and populations of the reviews using an evidence mapping approach.

STUDY DESIGN AND SETTING

A structured search for systematic reviews concerning COVID-19 was performed using PubMed, Embase, Cochrane Library, Campbell Library, Web of Science, CBM, WanFang Data, CNKI, and CQVIP from inception until June 2020. The quality of each review was assessed using the Assessment of Multiple Systematic Reviews 2 (AMSTAR 2) checklist and the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) checklist.

RESULTS

In total, 243 systematic reviews met the inclusion criteria, over 50% of which (128, 52.7%) were from 14 developing countries, with China contributing the most reviews (76, 31.3%). In terms of methodological quality of the studies, 30 (12.3%) were of moderate quality, 63 (25.9%) were of low quality, and 150 (61.7%) were of critically low quality. In terms of reporting quality, the median (interquartile range) PRISMA score was 14 (10-18). Regarding the topics of the reviews, 24 (9.9%) focused on the prevalence of COVID-19, 69 (28.4%) focused on the clinical manifestations, 30 (12.3%) focused on etiology, 43 (17.7%) focused on diagnosis, 65 (26.7%) focused on treatment, 104 (42.8%) focused on prognosis, and 25 (10.3%) focused on prevention. These studies mainly focused on general patients with COVID-19 (161, 66.3%), followed by children (22, 9.1%) and pregnant patients (18, 7.4%).

CONCLUSION

This study systematically evaluated the methodological and reporting quality of systematic reviews of COVID-19, summarizing and analyzing trends in their clinical topics, author countries, and study populations.

A comprehensive overview of vaccines developed for pandemic viral pathogens over the past two decades including those in clinical trials for the current novel SARS-CoV-2

The unprecedented coronavirus disease 2019 (COVID-19) is triggered by a novel strain of coronavirus namely, Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2). Researchers are working around the clock to control this pandemic and consequent waves of viral reproduction, through repurposing existing drugs as well as designing new vaccines. Several countries have hastened vaccine design and clinical trials to quickly address this outbreak. Currently, more than 250 aspirants against SARS-CoV-2 are in progress, including mRNA-replicating or non-replicating viral vectored-, DNA-, autologous dendritic cell-based-, and inactivated virus-vaccines. Vaccines work by prompting effector mechanisms such as cells/molecules, which target quickly replicating pathogens and neutralize their toxic constituents. Vaccine-stimulated immune effectors include adjuvant, affinity, avidity, affinity maturation, antibodies, antigen-presenting cells, B lymphocytes, carrier protein, CD4+ T-helper cells. In this review, we describe updated information on the various vaccines available over the last two decades, along with recent progress in the ongoing battle developing 63 diverse vaccines against SARS-CoV-2. The inspiration of our effort is to convey the current investigation focus on registered clinical trials (as of January 08, 2021) that satisfy the safety and efficacy criteria of international wide vaccine development.

The effect of acupoint herbal patching on the quality of life of patients recovering from COVID-19: A protocol for systematic review and meta analysis

BACKGROUND

There is a worldwide outbreak of COVID-19, and as the number of patients increases, an increasing number of patients are recovering. However, no relevant systematic review or meta-analysis has been designed to evaluate the effects of acupoint herbal patching on the life of patients recovering from COVID-19.

METHODS

The following electronic databases will be searched from the respective dates of database inception to April 20, 2021: The Cochrane Library, Web of Science, EMBASE, MEDLINE, China National Knowledge Infrastructure (CNKI), Chinese Biomedical Literature Database (CBM), Wanfang database, the Chinese Scientific Journal Database (VIP), and other sources. All published randomized controlled trials in English or Chinese related to acupoint herbal patching for COVID-19 will be included. The primary outcome was the timing of the influence of acupoint herbal patching on the quality of life of convalescent patients. Secondary outcomes were accompanying symptoms (such as myalgia, expectoration, stuffiness, runny nose, pharyngalgia, anhelation, chest distress, dyspnea, crackles, headache, nausea, vomiting, anorexia, diarrhea) disappearance rate, negative COVID-19 results rate on two consecutive occasions (not on the same day), average hospitalization time, clinical curative effect, and improved quality of life.

RESULTS

The main purpose of this systematic review protocol was to assess the effectiveness and safety of acupoint herbal patching therapy for treating patients recovering from COVID-19.

CONCLUSION

The conclusion of our study will provide evidence to judge whether acupoint herbal patching is an effective intervention for the quality of life in patients recovering.

PROSPERO REGISTRATION NUMBER

CRD42021246550.

Dietary Supplements for COVID-19

Coronavirus disease 2019 (COVID-19) is a highly contagious infectious disease that can rapidly escalate to respiratory failure and death. It has infected millions of people worldwide. The trajectory of this disease continues to progress in some areas of the United States and worldwide. The Institute for Health Metrics now predicts a resurgence of infections in the fall of 2020. The pathogenesis of COVID-19 includes an inflammatory phase with either resolution or the potential to accelerate to a cytokine storm, characterized by high interleukin (IL)-6 and other inflammatory markers. COVID-19 is a condition without a gold-standard treatment. The US Federal Drug Administration (FDA) issued an emergency use authorization for remdesivir in severe cases of COVID-19, which shortened the recovery time in hospitalized patients with lower respiratory tract infection in one study. Although several vaccine trials are underway, no vaccines are available for primary prevention of COVID-19 at this time. Dietary supplement sales have dramatically risen during the COVID-19 pandemic despite depressed economic conditions. Commonly used immune-modulating dietary supplements, including vitamin D, ascorbic acid, zinc, and melatonin, are reviewed in this manuscript highlighting biological plausibility for salutary benefit against COVID-19. Ongoing clinical trials recruiting subjects at the time of this writing are provided for each dietary supplement.

Super-rapid race for saving lives by developing COVID-19 vaccines

The pandemic of coronavirus disease 2019 (COVID-19) caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has affected millions of people and claimed thousands of lives. Starting in China, it is arguably the most precipitous global health calamity of modern times. The entire world has rocked back to fight against the disease and the COVID-19 vaccine is the prime weapon. Even though the conventional vaccine development pipeline usually takes more than a decade, the escalating daily death rates due to COVID-19 infections have resulted in the development of fast-track strategies to bring in the vaccine under a year’s time. Governments, companies, and universities have networked to pool resources and have come up with a number of vaccine candidates. Also, international consortia have emerged to address the distribution of successful candidates. Herein, we summarize these unprecedented developments in vaccine science and discuss the types of COVID-19 vaccines, their developmental strategies, and their roles as well as their limitations.

Perception of COVID-19 Vaccination Amongst Physicians in Colombia

Introduction: The SARS-CoV-2/COVID-19 pandemic has triggered the need to develop rapidly effective and safe vaccines to prevent infection, particularly in those at-risk populations such as medical personnel. This study's objective was to assess the perception of COVID-19 vaccination amongst Colombian physicians featuring two different scenarios of COVID-19 vaccination. Methods: A cross-sectional analytical study was carried out through an online survey directed at medical staff in several cities in Colombia. The percentage of physicians who have a positive perception to be vaccinated and the associated factors that determine that decision were determined. A binomial regression analysis adjusted for age and sex was carried out, taking as a dependent variable the acceptance of free vaccination with an effectiveness of 60 and 80%. The most significant factors were determined in the non-acceptance of vaccination. Results: Between 77.0% and 90.7% of physicians in Colombia accept COVID-19 vaccination, according to the scenario evaluated where the vaccine's effectiveness was 60 or 80%, respectively. Medical specialty, having never paid for a vaccine, recommending the administration of the vaccine to their parents or people over 70 years, and dispensing the vaccine to their children, were the factors to consider to be vaccinated for free with an effectiveness of 60% and 80%. Conclusions: There is a high perception of the intention to vaccinate physicians in Colombia against COVID-19, and this is very similar to that of the general population.

Computational studies by molecular docking of some antiviral drugs with COVID-19 receptors are an approach to medication for COVID-19

The COVID-19 outbreak is a matter of concern worldwide due to unavailability of promising treatment comprising medication or vaccination till date. The discovery of antiviral drug is of immense importance in the existing spread of novel coronavirus. The goal of the present study was to evolve an opposite antiviral drug against the novel COVID-19 virus. A directly succeeding perspective would be to use the prevailing influential drugs from several antimicrobial and chemotherapeutic agents. The encouraging approach is to identify promising drug molecules and compounds through virtual screening via molecular docking of FDA-approved drugs and some previously synthesized pyridone and coumarin derivatives for probable therapeutic outcome. In this conceptual milieu, an effort has been made to propose a computational in silico relationship among FDA-approved drugs and coronavirus-associated receptors and proteins. The study results were evaluated on the basis of a dock score by using molecular operating environment. Out of 15 compounds screened, the compounds with the best docking scores toward their targets was 3d. Therefore, compound 3d deserves further investigations and clinical trials as a possible therapeutic inhibitor of the COVID-19 caused by the novel SARS-CoV-2.

An overview of vaccine development for COVID-19

The COVID-19 pandemic continues to endanger world health and the economy. The causative SARS-CoV-2 coronavirus has a unique replication system. The end point of the COVID-19 pandemic is either herd immunity or widespread availability of an effective vaccine. Multiple candidate vaccines - peptide, virus-like particle, viral vectors (replicating and nonreplicating), nucleic acids (DNA or RNA), live attenuated virus, recombinant designed proteins and inactivated virus - are presently under various stages of expansion, and a small number of vaccine candidates have progressed into clinical phases. At the time of writing, three major pharmaceutical companies, namely Pfizer and Moderna, have their vaccines under mass production and administered to the public. This review aims to investigate the most critical vaccines developed for COVID-19 to date.

DNA vaccines against COVID-19: Perspectives and challenges

The coronavirus disease 2019 (COVID-19) is caused by a novel coronavirus known as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is associated with several fatal cases worldwide. The rapid spread of this pathogen and the increasing number of cases highlight the urgent development of vaccines. Among the technologies available for vaccine development, DNA vaccination is a promising alternative to conventional vaccines. Since its discovery in the 1990s, it has been of great interest because of its ability to elicit both humoral and cellular immune responses while showing relevant advantages regarding producibility, stability, and storage. This review aimed to summarize the current knowledge and advancements on DNA vaccines against COVID-19, particularly those in clinical trials.

COVID-19: Characteristics and Therapeutics

Novel coronavirus (COVID-19 or 2019-nCoV or SARS-CoV-2), which suddenly emerged in December 2019 is still haunting the entire human race and has affected not only the healthcare system but also the global socioeconomic balances. COVID-19 was quickly designated as a global pandemic by the World Health Organization as there have been about 98.0 million confirmed cases and about 2.0 million confirmed deaths, as of January 2021. Although, our understanding of COVID-19 has significantly increased since its outbreak, and multiple treatment approaches and pharmacological interventions have been tested or are currently under development to mitigate its risk-factors. Recently, some vaccine candidates showed around 95% clinical efficacy, and now receiving emergency use approvals in different countries. US FDA recently approved BNT162 and mRNA-1273 vaccines developed by Pfizer/BioNTech and Moderna Inc. for emergency use and vaccination in the USA. In this review, we present a succinct overview of the SARS-CoV-2 virus structure, molecular mechanisms of infection, COVID-19 epidemiology, diagnosis, and clinical manifestations. We also systematize different treatment strategies and clinical trials initiated after the pandemic outbreak, based on viral infection and replication mechanisms. Additionally, we reviewed the novel pharmacological intervention approaches and vaccine development strategies against COVID-19. We speculate that the current pandemic emergency will trigger detailed studies of coronaviruses, their mechanism of infection, development of systematic drug repurposing approaches, and novel drug discoveries for current and future pandemic outbreaks.

Review on Up-to-Date Status of Candidate Vaccines for COVID-19 Disease

The global pandemic of COVID-19 caused by SARS-CoV-2 continues to spread and poses serious threats to public health and economic stability throughout the world. Thus, to protect the global population, developing safe and effective vaccines is mandatory to control the spread of SARS-CoV-2 pandemic. Since genomic sequences of SARS-CoV-2 and SARS-CoV-1 have similarity and use the same receptor (ACE2), it is important to learn from the development of SARS-CoV-1 vaccines for the development of SARS-CoV-2 vaccines. Normally vaccine development takes 10-15 years but vaccine development against SARS-CoV2 is going on at a very fast pace resulting in almost breakthrough methods of vaccine development by several research institutions. The whole process of vaccine development including clinical trials gets shortened and may be fast tracked to 15-18 months. Global collaborations and increased research efforts among the scientific community have led to more than 214 candidate vaccines globally. The current review highlights the different approaches and technologies used around the world for the design and development of the vaccines and also focuses on the recent status of the SARS-CoV-2 vaccine candidates under development by various institutions to combat the world threat of COVID-19 pandemic.

Race to arsenal COVID-19 therapeutics: Current alarming status and future directions

The on-going pandemic of COVID-19 wreaked by a viral infection of SARS-CoV-2, has generated a catastrophic plight across the globe. Interestingly, one of the hallmarks of COVID-19 is the so-called 'cytokine storm' due to attack of SARS-Cov-2 in the lungs. Considering, mesenchymal stem cells (MSCs) therapy could contribute against SARS-CoV-2 viruses attack because of their immune modulatory and anti-inflammatory ability linked to their stemness, to the arsenal of treatments for COVID-19. Another novel therapeutic strategies include the blockade of rampant generation of pro-inflammatory mediators like acute respiratory distress syndrome (ARDS), degradation of viral protein capsids by PROTACs, composed of Ubiquitin-proteasome framework, and ubiquitination-independent pathway directing the SARS-CoV-2 nucleocapsid protein (nCoV N) and proteasome activator (PA28γ), etc. This review is consequently an endeavour to highlight the several aspects of COVID-19 with incorporation of important treatment strategies discovered to date and putting the real effort on the future directions to put them into the perspective.

Clinical HDAC Inhibitors Are Effective Drugs to Prevent the Entry of SARS-CoV2

The outbreak of COVID-19 by the end of 2019 has posed serious health threats to humanity and jeopardized the global economy. However, no effective drugs are available to treat COVID-19 currently and there is a great demand to fight against it. Here, we combined computational screening and an efficient cellular pseudotyped virus system, confirming that clinical HDAC inhibitors can efficiently prevent SARS-CoV-2 and potentially be used to fight against COVID-19.

The under-reported role of toxic substance exposures in the COVID-19 pandemic

Coronavirus disease 2019 (COVID-19) and previous pandemics have been viewed almost exclusively as virology problems, with toxicology problems mostly being ignored. This perspective is not supported by the evolution of COVID-19, where the impact of real-life exposures to multiple toxic stressors degrading the immune system is followed by the SARS-CoV-2 virus exploiting the degraded immune system to trigger a chain of events ultimately leading to COVID-19. This immune system degradation from multiple toxic stressors (chemical, physical, biological, psychosocial stressors) means that attribution of serious consequences from COVID-19 should be made to the virus-toxic stressors nexus, not to any of the nexus constituents in isolation. The leading toxic stressors (identified in this study as contributing to COVID-19) are pervasive, contributing to myriad chronic diseases as well as immune system degradation. They increase the likelihood for comorbidities and mortality associated with COVID-19.

For the short-term, tactical/reactive virology-focused treatments are of higher priority than strategic/proactive toxicology-focused treatments, although both could be implemented in parallel to reinforce each other. However, for long-term pandemic prevention, toxicology-based approaches should be given higher priority than virology-based approaches. Since current COVID-19 treatments globally ignore the toxicology component almost completely, only limited benefits can be expected from these treatments.

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Toxicology contributions to COVID-19 are mostly ignored relative to virology contributions.

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Exposure to myriad toxic substances degrades the immune system, whose resulting dysfunction is then exploited by SARS-CoV-2 to result in COVID-19.

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Attribution of serious consequences from COVID-19 should be made to the virus-toxic stressors combination nexus, not to any of the nexus constituents in isolation.

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Effective treatments need to address toxicology and virology interactions.

Research Progress of Chloroquine and Hydroxychloroquine on the COVID-19 and Their Potential Risks in Clinic Use

In December 2019, a severe outbreak of a novel coronavirus (COVID-19) occurred in the whole world, posing a great threat to people's health. With the outbreak and development of the epidemic, how to improve the cure rate, find effective drugs against this virus, has been the most urgent problem. Chloroquine (CQ) was verified effective against COVID-19 in vitro. As CQ's analogue, hydroxychloroquine (HCQ) was also reminded as a potential candidate for treating COVID-19. This review summarizes the latest clinical trials of CQ and HCQ against COVID-19 and its therapeutic regimen in China aiming to share their current usage to the whole world and provide insight into its appropriate future use in the treatment of COVID-19. Through searching the CNKI and Wangfang databases in Chinese language and PubMed, EMBASE, and Ovid databases in English language to identify published reports with the keywords including "coronavirus/COVID, chloroquine, hyroxychloroquine" in alone or combined, we found out the potential preclinical or clinical evidence for using CQ and HCQ against COVID-19. Consequently, we also searched the website of Chinese Clinical Trial Registry (http://www.chictr.org.cn/) till the day on 27th, June, 2020. This review found that there are 23 programs aimed to treat the different phases under COVID-19 pipeline in clinic with CQ and HCQ, totally. The inclusion criteria, exclusion criteria and therapeutic regimen were all shared to consult. Among them, seven have been canceled due to lack of patients or other objective factors. There are two trials have completed, which the potential relationship between usage and adverse reactions was discussed emphatically. Through literature research, we suggested that paid close attention to retinal toxicity and ophthalmologic adverse symptom of CQ and HCQ. And the outcome of HCQ in clinic shows better than CQ especially in protective effect with low dosage.