Review of the Emerging Evidence Demonstrating the Efficacy of Ivermectin in the Prophylaxis and Treatment of COVID-19

Using a Systems Approach to Explore the Mechanisms of Interaction Between Severe Covid-19 and Its Coronary Heart Disease Complications

Frontiers requested research on how a systems approach can explore the mechanisms of cardiovascular complications in Covid-19. The focus of this paper will thus be on these detailed mechanisms. It will elucidate the integrated pathogenic pathways based on an extensive review of literature. Many severe Covid-19 cases and deaths occur in patients with chronic cardiovascular comorbidities. To help understand all the mechanisms of this interaction, Covid-19 complications were integrated into a pre-existing systems-based coronary heart disease (CHD) model. Such a complete model could not be found in literature. A fully integrative view could be valuable in identifying new pharmaceutical interventions, help understand how health factors influence Covid-19 severity and give a fully integrated explanation for the Covid-19 death spiral phenomenon seen in some patients. Covid-19 data showed that CHD hallmarks namely, Hypercoagulability, Hypercholesterolemia, Hyperglycemia/Hyperinsulinemia, Inflammation and Hypertension have an important effect on disease severity. The pathogenic pathways that Covid-19 activate in CHD were integrated into the CHD model. This fully integrated model presents a visual explanation of the mechanism of interaction between CHD and Covid-19 complications. This includes a detailed integrated explanation of the death spiral as a result of interactions between Inflammation, endothelial cell injury, Hypercoagulability and hypoxia. Additionally, the model presents the aggravation of this death spiral through the other CHD hallmarks namely, Hyperglycemia/Hyperinsulinemia, Hypercholesterolemia, and/or Hypertension. The resulting model further suggests systematically how the pathogenesis of nine health factors (stress, exercise, smoking, etc.) and seven pharmaceutical interventions (statins, salicylates, thrombin inhibitors, etc.) may either aggravate or suppress Covid-19 severity. A strong association between CHD and Covid-19 for all the investigated health factors and pharmaceutical interventions, except for β-blockers, was found. It is further discussed how the proposed model can be extended in future to do computational analysis to help assess the risk of Covid-19 in cardiovascular disease. With insight gained from this study, recommendations are made for future research in potential new pharmacotherapeutics. These recommendations could also be beneficial for cardiovascular disease, which killed five times more people in the past year than Covid-19.

Unresolved COVID Controversies: 'Normal science' and potential non-scientific influences

ABSTRACTThe COVID-19 health crisis has so far involved enormous consequences in human pain, suffering and death. While biomedical science responded early, its response has been marked by several controversies between what appeared to be mainstream perspectives, and diverse alternative views; far from leading to productive debate, controversies often preceded polarisation and, allegedly, exclusion and even censorship of alternative views, followed by the pretense of scientific consensus. This paper describes and discusses the main controversies in the production of COVID biomedical knowledge and derived control measures, to establish if alternative positions are also legitimate from a 'normal science' perspective (rather than comparing them for superiority); explores potential non-scientific explanations of the alleged exclusion of certain views; and analyzes ethical issues implied. The operation of non-scientific factors in scientific and regulatory processes (e.g. various forms of subtle corruption) has been documented in the past; the intervention of such influences in the mishandling of controversies (i.e. on early management, non-pharmacological prevention and vaccination) cannot be ruled out and deserves further investigation. Some of these controversies, increasingly visible in the public domain, also involve ethical challenges that need urgent attention. Polarisation, censorship and dogma are foreign to true science and must be left behind.

Repurposing the drug, ivermectin, in COVID-19: toxicological points of view

The global COVID-19 pandemic has affected the world's population by causing changes in behavior, such as social distancing, masking, restricting people's movement, and evaluating existing medication as potential therapies. Many pre-existing medications such as tocilizumab, ivermectin, colchicine, interferon, and steroids have been evaluated for being repurposed to use for the treatment of COVID-19. None of these agents have been effective except for steroids and, to a lesser degree, tocilizumab. Ivermectin has been one of the suggested repurposed medications which exhibit an in vitro inhibitory activity on SARS-CoV-2 replication. The most recommended dose of ivermectin for the treatment of COVID-19 is 150-200 µg/kg twice daily. As ivermectin adoption for COVID-19 increased, the Food and Drug Administration (FDA) issued a warning on its use during the pandemic. However, the drug remains of interest to clinicians and has shown some promise in observational studies. This narrative reviews the toxicological profile and some potential therapeutic effects of ivermectin. Based on the current dose recommendation, ivermectin appears to be safe with minimum side effects. However, serious questions remain about the effectiveness of this drug in the treatment of patients with COVID-19.

Ivermectin for COVID-19: Addressing Potential Bias and Medical Fraud

Ivermectin has become a controversial potential medicine for coronavirus disease 2019. Some early studies suggested clinical benefits in treatment of infection. However, the body of evidence includes studies of varying quality. Furthermore, some trials have now been identified as potentially fraudulent. We present a subgroup meta-analysis to assess the effects of stratifying by trial quality on the overall results. The stratification is based on the Cochrane Risk of Bias measures and raw data analysis where possible. The results suggest that the significant effect of ivermectin on survival was dependent on largely poor-quality studies. According to the potentially fraudulent study (risk ratio [RR], 0.08; 95% CI, 0.02-0.35), ivermectin improved survival ~12 times more in comparison with low-risk studies (RR, 0.96; 95% CI, 0.56-1.66). This highlights the need for rigorous quality assessments, for authors to share patient-level data, and for efforts to avoid publication bias for registered studies. These steps are vital to facilitate accurate conclusions on clinical treatments.

Ivermectin in COVID-19 Management: What is the current evidence?

Ivermectin (IVM), an approved anthelminthic drug, has been reported to have antiviral, antibacterial, and anticancer activities. Antiviral activity is due to the inhibition of nuclear cargo importin (IMP) protein. The anti-SARS CoV-2 activity through in vitro study was first reported by an Australian team. Later, many studies were conducted, and most of the study results were available as non-peer reviewed preprints. In this narrative review, literature on the clinical studies conducted with ivermectin from published articles, preprints, and unpublished evidence are collected till 13th June 2021 and they are discussed based on the severity of COVID-19 disease. Out of the 23 peer-reviewed published articles, 13 studies were randomized controlled trials and the remaining were either prospective interventional, prospective observational, retrospective cohort, cross-sectional, or case series type of studies; additionally, there were 10 randomized controlled trials available as preprints. In most of the studies, ivermectin was used in combination with doxycycline, azithromycin or other drugs. Some of the studies suggested either higher dose and/ or increased duration of ivermectin use to achieve favorable effects. In this review, articles on the prophylactic role of ivermectin in COVID-19 are also discussed - wherein the results are more promising. Despite accumulating evidence suggest the possible use of ivermectin, the final call to incorporate ivermectin in the management of COVID-19 is still inconclusive.

SIT1 transporter as a potential novel target in treatment of COVID-19

Studies published earlier this year demonstrated the association of the solute carrier SLC6A20 gene with the risk and severity of COVID-19. The SLC6A20 protein product (Sodium-dependent Imino Transporter 1 (SIT1)) is involved in the transport of amino acids, including glycine. Here we summarized the results of recent studies demonstrating the interaction of SIT1 with the ACE2 receptor for SARS-CoV-2 as well as an observed association of SLC6A20 with the risk and traits of Type 2 diabetes (T2D). Recently, it was also proposed that SLC6A20 represents the novel regulator of glycine levels and that glycine has beneficial effects against the proinflammatory cytokine secretion induced by SARS-CoV-2 infection. Ivermectin, as a partial agonist of glycine-gated chloride channels, was also recently suggested to interfere with the COVID-19 cytokine storm by inducing the activation of glycine receptors. Furthermore, plasma glycine levels are found to be decreased in diabetic patients. Thus, further clinical trials are warranted to confirm the potential favorable effects of targeting the SIT1 transporter and glycine levels in the treatment of COVID-19, particularly for the severe case of disease associated with hyperglycemia, inflammation, and T2D. These findings suggest that SIT1 may potentially represent one of the missing pieces in the complex puzzle observed between these two pandemic diseases and the potential novel target for their efficient treatment.

Identification and Development of Therapeutics for COVID-19

After emerging in China in late 2019, the novel coronavirus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) spread worldwide, and as of mid-2021, it remains a significant threat globally. Only a few coronaviruses are known to infect humans, and only two cause infections similar in severity to SARS-CoV-2: Severe acute respiratory syndrome-related coronavirus, a species closely related to SARS-CoV-2 that emerged in 2002, and Middle East respiratory syndrome-related coronavirus, which emerged in 2012. Unlike the current pandemic, previous epidemics were controlled rapidly through public health measures, but the body of research investigating severe acute respiratory syndrome and Middle East respiratory syndrome has proven valuable for identifying approaches to treating and preventing novel coronavirus disease 2019 (COVID-19). Building on this research, the medical and scientific communities have responded rapidly to the COVID-19 crisis and identified many candidate therapeutics. The approaches used to identify candidates fall into four main categories: adaptation of clinical approaches to diseases with related pathologies, adaptation based on virological properties, adaptation based on host response, and data-driven identification (ID) of candidates based on physical properties or on pharmacological compendia. To date, a small number of therapeutics have already been authorized by regulatory agencies such as the Food and Drug Administration (FDA), while most remain under investigation. The scale of the COVID-19 crisis offers a rare opportunity to collect data on the effects of candidate therapeutics. This information provides insight not only into the management of coronavirus diseases but also into the relative success of different approaches to identifying candidate therapeutics against an emerging disease. IMPORTANCE The COVID-19 pandemic is a rapidly evolving crisis. With the worldwide scientific community shifting focus onto the SARS-CoV-2 virus and COVID-19, a large number of possible pharmaceutical approaches for treatment and prevention have been proposed. What was known about each of these potential interventions evolved rapidly throughout 2020 and 2021. This fast-paced area of research provides important insight into how the ongoing pandemic can be managed and also demonstrates the power of interdisciplinary collaboration to rapidly understand a virus and match its characteristics with existing or novel pharmaceuticals. As illustrated by the continued threat of viral epidemics during the current millennium, a rapid and strategic response to emerging viral threats can save lives. In this review, we explore how different modes of identifying candidate therapeutics have borne out during COVID-19.

Efficacy and safety of ivermectin for the treatment of COVID-19: a systematic review and meta-analysis

BACKGROUND

Ivermectin became a popular choice for COVID-19 treatment among clinicians and the public following encouraging results from pre-print trials and in vitro studies. Early reviews recommended the use of ivermectin based largely on non-peer-reviewed evidence, which may not be robust. This systematic review and meta-analysis assessed the efficacy and safety of ivermectin for treating COVID-19 based on peer-reviewed randomized controlled trials (RCTs) and observational studies (OSs).

METHODS

MEDLINE, EMBASE and PubMed were searched from 1 January 2020 to 1 September 2021 for relevant studies. Outcomes included time to viral clearance, duration of hospitalization, mortality, incidence of mechanical ventilation and incidence of adverse events. RoB2 and ROBINS-I were used to assess risk of bias. Random-effects meta-analyses were conducted. GRADE was used to evaluate quality of evidence.

RESULTS

Three OSs and 14 RCTs were included in the review. Most RCTs were rated as having some concerns in regards to risk of bias, while OSs were mainly rated as having a moderate risk of bias. Based on meta-analysis of RCTs, the use of ivermectin was not associated with reduction in time to viral clearance, duration of hospitalization, incidence of mortality and incidence of mechanical ventilation. Ivermectin did not significantly increase incidence of adverse events. Meta-analysis of OSs agrees with findings from RCT studies.

CONCLUSIONS

Based on very low to moderate quality of evidence, ivermectin was not efficacious at managing COVID-19. Its safety profile permits its use in trial settings to further clarify its role in COVID-19 treatment.

PROTOCOL REGISTRATION

The review was prospectively registered in PROSPERO (CRD42021275302).

The military as a neglected pathogen transmitter, from the nineteenth century to COVID-19: a systematic review

Background

The risk of outbreaks escalating into pandemics has soared with globalization. Therefore, understanding transmission mechanisms of infectious diseases has become critical to formulating global public health policy. This systematic review assessed evidence in the medical and public health literature for the military as a disease vector.

Methods

We searched 3 electronic databases without temporal restrictions. Two researchers independently extracted study data using a standardized form. Through team discussions, studies were grouped according to their type of transmission mechanism and direct quotes were extracted to generate themes and sub-themes. A content analysis was later performed and frequency distributions for each theme were generated.

Results

Of 6477 studies, 210 met our inclusion criteria and provided evidence, spanning over two centuries (1810–2020), for the military as a pathogen transmitter, within itself or between it and civilians. Biological mechanisms driving transmission included person-to-person transmission, contaminated food and water, vector-borne, and airborne routes. Contaminated food and/or water were the most common biological transmission route. Social mechanisms facilitating transmission included crowded living spaces, unhygienic conditions, strenuous working, training conditions, absent or inadequate vaccination programs, pressure from military leadership, poor compliance with public health advice, contractor mismanagement, high-risk behaviours, and occupation-specific freedom of movement. Living conditions were the most common social transmission mechanism, with young, low ranking military personnel repeatedly reported as the most affected group. Selected social mechanisms, such as employment-related freedom of movement, were unique to the military as a social institution. While few studies explicitly studied civilian populations, considerably more contained information that implied that civilians were likely impacted by outbreaks described in the military.

Conclusions

This study identified features of the military that pose a significant threat to global health, especially to civilian health in countries with substantial military presence or underdeveloped health systems. While biological transmission mechanisms are shared by other social groups, selected social transmission mechanisms are unique to the military. As an increasingly interconnected world faces the challenges of COVID-19 and future infectious diseases, the identified features of the military may exacerbate current and similar challenges and impair attempts to implement successful and equitable global public health policies.

Supplementary Information

The online version contains supplementary material available at 10.1186/s41256-021-00232-0.

Covid-19 pandemic: What is the truth?

The ongoing “pandemic” involving the severe acute respiratory syndrome coronavirus 2 virus (SARS-CoV-2) has several characteristics that make it unique in the history of pandemics. This entails not only the draconian measures that some countries and individual states within the United States and initiated and made policy, most of which are without precedent or scientific support, but also the completely unscientific way the infection has been handled. For the 1^st time in medical history, major experts in virology, epidemiology, infectious diseases, and vaccinology have not only been ignored, but are also demonized, marginalized and in some instances, become the victim of legal measures that can only be characterized as totalitarian. Discussions involving various scientific opinions have been eliminated, top scientists have been frightened into silence by threats to their careers, physicians have lost their licenses, and the concept of early treatment has been virtually eliminated. Hundreds of thousands of people have died needlessly as a result of, in my opinion and the opinion of others, poorly designed treatment protocols, mostly stemming from the Center for Disease Control and Prevention, which have been rigidly enforced among all hospitals. The economic, psychological, and institutional damage caused by these unscientific policies is virtually unmeasurable. Whole generations of young people will suffer irreparable damage, both physical and psychological, possibly forever. The truth must be told.

Cell fusion as a link between the SARS-CoV-2 spike protein, COVID-19 complications, and vaccine side effects

A distinctive feature of the SARS-CoV-2 spike protein is its ability to efficiently fuse cells, thus producing syncytia found in COVID-19 patients. This commentary proposes how this ability enables spike to cause COVID-19 complications as well as side effects of COVID-19 vaccines, and suggests how these effects can be prevented.

The economic impact of lockdowns: A theoretical assessment

The sudden appearance of the SARS-CoV-2 virus and the onset of the COVID-19 pandemic triggered extreme and open-ended "lockdowns" to manage the disease. Should these drastic interventions be the blueprint for future epidemics? We construct an analytical framework, based on the theory of random matching, which makes explicit how epidemics spread through economic activity. Imposing lockdowns by assumption not only prevents contagion and reduces healthcare costs, but also disrupts income-generation processes. We characterize how lockdowns impact the contagion process and social welfare. Numerical analysis suggests that protracted, open-ended lockdowns are generally suboptimal, bringing into question the policy responses seen in many countries.

Effectiveness and safety of Ivermectin in COVID-19 patients: A prospective study at a safety-net hospital

Ivermectin has been found to inhibit severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) replication in vitro. It is unknown whether this inhibition of SARS‐CoV‐2 replication correlates with improved clinical outcomes. To assess the effectiveness and safety of ivermectin in hospitalized patients with COVID‐19. A total of 286 patients with COVID‐19 were included in the study. Univariate analysis of the primary mortality outcome and comparisons between treatment groups were determined. Logistic regression and propensity score matching (PSM) was used to adjust for confounders. Patients in the ivermectin group received 2 doses of Ivermectin at 200 μg/kg in addition to usual clinical care on hospital Days 1 and 3. The ivermectin group had a significantly higher length of hospital stay than the control group; however, this significance did not maintain on multivariable logistic regression analysis. The length of intensive care unit (ICU) stay and duration of mechanical ventilation were longer in the control group. However, a mortality benefit was not seen with ivermectin treatment before and after PSM (p values = 0.07 and 0.11, respectively). ICU admission, and intubation rate were not significantly different between the groups (p = 0.49, and p = 1.0, respectively). No differences were found between groups regarding the length of hospital stay, ICU admission, intubation rate, and in‐hospital mortality.

The Drug Repurposing for COVID-19 Clinical Trials Provide Very Effective Therapeutic Combinations: Lessons Learned From Major Clinical Studies

SARS-CoV-2 has spread across the globe in no time. In the beginning, people suffered due to the absence of efficacious drugs required to treat severely ill patients. Nevertheless, still, there are no established therapeutic molecules against the SARS-CoV-2. Therefore, repurposing of the drugs started against SARS-CoV-2, due to which several drugs were approved for the treatment of COVID-19 patients. This paper reviewed the treatment regime for COVID-19 through drug repurposing from December 8, 2019 (the day when WHO recognized COVID-19 as a pandemic) until today. We have reviewed all the clinical trials from RECOVERY trials, ACTT-1 and ACTT-2 study group, and other major clinical trial platforms published in highly reputed journals such as NEJM, Lancet, etc. In addition to single-molecule therapy, several combination therapies were also evaluated to understand the treatment of COVID-19 from these significant clinical trials. To date, several lessons have been learned on the therapeutic outcomes for COVID-19. The paper also outlines the experiences gained during the repurposing of therapeutic molecules (hydroxychloroquine, ritonavir/ lopinavir, favipiravir, remdesivir, ivermectin, dexamethasone, camostatmesylate, and heparin), immunotherapeutic molecules (tocilizumab, mavrilimumab, baricitinib, and interferons), combination therapy, and convalescent plasma therapy to treat COVID-19 patients. We summarized that anti-viral therapeutic (remdesivir) and immunotherapeutic (tocilizumab, dexamethasone, and baricitinib) therapy showed some beneficial outcomes. Until March 2021, 4952 clinical trials have been registered in ClinicalTrials.gov toward the drug and vaccine development for COVID-19. More than 100 countries have participated in contributing to these clinical trials. Other than the registered clinical trials (medium to large-size), several small-size clinical trials have also been conducted from time to time to evaluate the treatment of COVID-19. Four molecules showed beneficial therapeutic to treat COVID-19 patients. The short-term repurposing of the existing drug may provide a successful outcome for COVID-19 patients. Therefore, more clinical trials can be initiated using potential anti-viral molecules by evaluating in different phases of clinical trials.

Cross-testing of direct-action antivirals, universal vaccines, or search for host-level antivirals: what will sooner lead to a generic capability to combat the emerging viral pandemics?

INTRODUCTION

Mitigation of future viral pandemics is an enormous technical problem, but its solution is essential for preservation of life, economic well-being, and social stability. The author examined host-level, direct action antiviral, and universal vaccine approaches while presenting a specific screening proposal.

AREAS COVERED

The author examined the most recent biomedical literature publicly available in the databases and identified the publications supporting the principle of cross-applicability of direct-action antivirals (DAA) within similar viral families and at greater phylogenetic distances.

EXPERT OPINION

Comparing different approaches, the author showed that the cocktails of DAAs, including parent compounds that passed Phase I trials need to be preemptively tested for all major viral families, approved, and stockpiled (or dual-use production facilities designated). The quick distribution of the pre-approved and pre-positioned antiviral cocktails (even of moderate efficiency) reduces mortality and economic damage many-fold, resulting in the trillion-scale savings in a pandemic context. This pre-positioning approach is only one in the combinatorial toolkit that needs to be included in the plan for all viral families of importance. A dedicated international public-private initiative can achieve savings in these proactive preparedness efforts, as well as to keep the focus of politicians and public on the problem.

Repositioning Ivermectin for Covid-19 treatment: Molecular mechanisms of action against SARS-CoV-2 replication

Ivermectin (IVM) is an FDA approved macrocyclic lactone compound traditionally used to treat parasitic infestations and has shown to have antiviral potential from previous in-vitro studies. Currently, IVM is commercially available as a veterinary drug but have also been applied in humans to treat onchocerciasis (river blindness - a parasitic worm infection) and strongyloidiasis (a roundworm/nematode infection). In light of the recent pandemic, the repurposing of IVM to combat SARS-CoV-2 has acquired significant attention. Recently, IVM has been proven effective in numerous in-silico and molecular biology experiments against the infection in mammalian cells and human cohort studies. One promising study had reported a marked reduction of 93% of released virion and 99.98% unreleased virion levels upon administration of IVM to Vero-hSLAM cells. IVM's mode of action centres around the inhibition of the cytoplasmic-nuclear shuttling of viral proteins by disrupting the Importin heterodimer complex (IMPα/β1) and downregulating STAT3, thereby effectively reducing the cytokine storm. Furthermore, the ability of IVM to block the active sites of viral 3CLpro and S protein, disrupts important machinery such as viral replication and attachment. This review compiles all the molecular evidence to date, in review of the antiviral characteristics exhibited by IVM. Thereafter, we discuss IVM's mechanism and highlight the clinical advantages that could potentially contribute towards disabling the viral replication of SARS-CoV-2. In summary, the collective review of recent efforts suggests that IVM has a prophylactic effect and would be a strong candidate for clinical trials to treat SARS-CoV-2.

Emerging and Established Histological Techniques for the Analysis of Thrombosis in COVID-19 Lungs

Coronavirus disease 2019 (COVID-19) is the potentially lethal disease that is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Patients with COVID-19 have an increased risk of thrombosis, but the role of thrombosis in the pathogenesis and progression of severe COVID-19 remains unclear. A better understanding of the contribution of thrombosis to the development and progression of COVID-19 could lead to the development of novel COVID-19 treatments. For this reason, established and emerging histological techniques have recently been used to analyze COVID-19 lungs quantitatively and visually and in two and three dimensions. The gold standard and novel state-of the-art histological techniques that have been used to assess thrombosis in COVID-19 lungs are described in this Mini Review.

Potential use of ivermectin for the treatment and prophylaxis of SARS-CoV-2 infection

PURPOSE OF THE STUDY

Currently no treatment has been proven to be efficacious for patients with early symptoms of COVID-19. Although most patients present mild or moderate symptoms, up to 5-10% may have a poor disease progression, so there is an urgent need for effective drugs, which can be administered even before the onset of severe symptoms, i.e. when the course of the disease is modifiable. Recently, promising results of several studies on oral ivermectin have been published, which has prompted us to conduct the present review of the scientific literature.

METHODS

A narrative review has been carried out, focusing on the following four main topics: a) short-term efficacy in the treatment of the disease, b) long-term efficacy in the treatment of patients with post-acute symptoms of COVID-19, c) efficacy in the prophylaxis of the disease, and c) safety of ivermectin.

RESULTS

The reviewed literature suggests that there seems to be sufficient evidence about the safety of oral ivermectin, as well as the efficacy of the drug in the early-treatment and the prophylaxis of COVID-19.

CONCLUSIONS

In the view of the available evidence, the Frontline COVID-19 Critical Care Alliance (FLCCC) recommends the use of oral ivermectin for both prophylaxis and early-treatment of COVID-19. Further well-designed studies should be conducted in order to explore the efficacy and safety of invermectin at low and high doses, following different dosing schedules, in both, the short and long-term treatment.

Beyond Vaccines: Clinical Status of Prospective COVID-19 Therapeutics

Since November 2019 the SARS-CoV-2 pandemic has caused nearly 200 million infection and more than 4 million deaths globally (Updated information from the World Health Organization, as on 2nd Aug 2021). Within only one year into the pandemic, several vaccines were designed and reached approval for the immunization of the world population. The remarkable protective effects of the manufactured vaccines are demonstrated in countries with high vaccination rates, such as Israel and UK. However, limited production capacities, poor distribution infrastructures and political hesitations still hamper the availability of vaccines in many countries. In addition, due to the emergency of SARS-CoV-2 variants with immune escape properties towards the vaccines the global numbers of new infections as well as patients developing severe COVID-19, remains high. New studies reported that about 8% of infected individuals develop long term symptoms with strong personal restrictions on private as well as professional level, which contributes to the long socioeconomic problems caused by this pandemic. Until today, emergency use-approved treatment options for COVID-19 are limited to the antiviral Remdesivir, a nucleoside analogue targeting the viral polymerase, the glucocorticosteroide Dexamethasone as well as neutralizing antibodies. The therapeutic benefits of these treatments are under ongoing debate and clinical studies assessing the efficiency of these treatments are still underway. To identify new therapeutic treatments for COVID-19, now and by the post-pandemic era, diverse experimental approaches are under scientific evaluation in companies and scientific research teams all over the world. To accelerate clinical translation of promising candidates, repurposing approaches of known approved drugs are specifically fostered but also novel technologies are being developed and are under investigation. This review summarizes the recent developments from the lab bench as well as the clinical status of emerging therapeutic candidates and discusses possible therapeutic entry points for the treatment strategies with regard to the biology of SARS-CoV-2 and the clinical course of COVID-19.

Ivermectin: a multifaceted drug of Nobel prize-honoured distinction with indicated efficacy against a new global scourge, COVID-19

In 2015, the Nobel Committee for Physiology or Medicine, in its only award for treatments of infectious diseases since six decades prior, honoured the discovery of ivermectin (IVM), a multifaceted drug deployed against some of the world's most devastating tropical diseases. Since March 2020, when IVM was first used against a new global scourge, COVID-19, more than 20 randomized clinical trials (RCTs) have tracked such inpatient and outpatient treatments. Six of seven meta-analyses of IVM treatment RCTs reporting in 2021 found notable reductions in COVID-19 fatalities, with a mean 31% relative risk of mortality vs. controls. During mass IVM treatments in Peru, excess deaths fell by a mean of 74% over 30 days in its ten states with the most extensive treatments. Reductions in deaths correlated with the extent of IVM distributions in all 25 states with p < 0.002. Sharp reductions in morbidity using IVM were also observed in two animal models, of SARS-CoV-2 and a related betacoronavirus. The indicated biological mechanism of IVM, competitive binding with SARS-CoV-2 spike protein, is likely non-epitope specific, possibly yielding full efficacy against emerging viral mutant strains.

Attenuation of clinical and immunological outcomes during SARS-CoV-2 infection by ivermectin

The devastating pandemic due to SARS-CoV-2 and the emergence of antigenic variants that jeopardize the efficacy of current vaccines create an urgent need for a comprehensive understanding of the pathophysiology of COVID-19, including the contribution of inflammation to disease. It also warrants for the search of immunomodulatory drugs that could improve disease outcome. Here, we show that standard doses of ivermectin (IVM), an anti-parasitic drug with potential immunomodulatory activities through the cholinergic anti-inflammatory pathway, prevent clinical deterioration, reduce olfactory deficit, and limit the inflammation of the upper and lower respiratory tracts in SARS-CoV-2-infected hamsters. Whereas it has no effect on viral load in the airways of infected animals, transcriptomic analyses of infected lungs reveal that IVM dampens type I interferon responses and modulates several other inflammatory pathways. In particular, IVM dramatically reduces the Il-6/Il-10 ratio in lung tissue and promotes macrophage M2 polarization, which might account for the more favorable clinical presentation of IVM-treated animals. Altogether, this study supports the use of immunomodulatory drugs such as IVM, to improve the clinical condition of SARS-CoV-2-infected patients.

Ivermectin as a SARS-CoV-2 Pre-Exposure Prophylaxis Method in Healthcare Workers: A Propensity Score-Matched Retrospective Cohort Study

BACKGROUND

Ivermectin is a drug that has been shown to be active against coronavirus disease 19 (COVID-19) in previous studies. Healthcare personnel are highly exposed to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Therefore, we decided to offer them ivermectin as a pre-exposure prophylaxis (PrEP) method.

PURPOSE

Primary outcome was to measure the number of healthcare workers with symptomatic SARS-CoV-2 infection and a positive reverse transcription polymerase chain reaction (RT-PCR) COVID-19 test in the ivermectin group and in the control group. Secondary outcome was to measure the number of sick healthcare workers with a positive RT-PCR COVID-19 test whose condition deteriorated and required hospitalization and/or an Intensive Care Unit (ICU), or who died, in the ivermectin group and in the control group.

MATERIAL AND METHODS

This observational and retrospective cohort study was carried out in two medical centers, Centro Medico Bournigal (CMBO) in Puerto Plata and Centro Medico Punta Cana (CMPC) in Punta Cana, Dominican Republic. The study began on June 29, 2020, and ended on July 26, 2020. A Statistical Package for Social Sciences (SPSS) Propensity Score Matching procedure was applied in a 1:1 ratio to homogeneously evaluate 271 healthcare personnel that adhered to a PrEP program with ivermectin at a weekly oral (PO) dose of 0.2 mg/kg, and 271 healthcare personnel who did not adhere to the program were assigned as a control group.

RESULTS

In 28 days of follow-up, significant protection of ivermectin preventing the infection from SARS-CoV-2 was observed: 1.8% compared to those who did not take it (6.6%; p-value = 0.006), with a risk reduction of 74% (HR 0.26, 95% CI [0.10,0.71]).  Conclusions: These results suggest that compassionate use of weekly ivermectin could be an option as a preventive method in healthcare workers and as an adjunct to immunizations, while further well-designed randomized controlled trials are developed to facilitate scientific consensus.

Ivermectin for preventing and treating COVID-19

BACKGROUND

Ivermectin, an antiparasitic agent used to treat parasitic infestations, inhibits the replication of viruses in vitro. The molecular hypothesis of ivermectin's antiviral mode of action suggests an inhibitory effect on severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) replication in the early stages of infection. Currently, evidence on efficacy and safety of ivermectin for prevention of SARS-CoV-2 infection and COVID-19 treatment is conflicting.

OBJECTIVES

To assess the efficacy and safety of ivermectin compared to no treatment, standard of care, placebo, or any other proven intervention for people with COVID-19 receiving treatment as inpatients or outpatients, and for prevention of an infection with SARS-CoV-2 (postexposure prophylaxis).

SEARCH METHODS

We searched the Cochrane COVID-19 Study Register, Web of Science (Emerging Citation Index and Science Citation Index), medRxiv, and Research Square, identifying completed and ongoing studies without language restrictions to 26 May 2021.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing ivermectin to no treatment, standard of care, placebo, or another proven intervention for treatment of people with confirmed COVID-19 diagnosis, irrespective of disease severity, treated in inpatient or outpatient settings, and for prevention of SARS-CoV-2 infection. Co-interventions had to be the same in both study arms.  We excluded studies comparing ivermectin to other pharmacological interventions with unproven efficacy.

DATA COLLECTION AND ANALYSIS

We assessed RCTs for bias, using the Cochrane risk of bias 2 tool. The primary analysis excluded studies with high risk of bias. We used GRADE to rate the certainty of evidence for the following outcomes 1. to treat inpatients with moderate-to-severe COVID-19: mortality, clinical worsening or improvement, adverse events, quality of life, duration of hospitalization, and viral clearance; 2. to treat outpatients with mild COVID-19: mortality, clinical worsening or improvement, admission to hospital, adverse events, quality of life, and viral clearance; (3) to prevent SARS-CoV-2 infection: SARS-CoV-2 infection, development of COVID-19 symptoms, adverse events, mortality, admission to hospital, and quality of life.

MAIN RESULTS

We found 14 studies with 1678 participants investigating ivermectin compared to no treatment, placebo, or standard of care. No study compared ivermectin to an intervention with proven efficacy. There were nine studies treating participants with moderate COVID-19 in inpatient settings and four treating mild COVID-19 cases in outpatient settings. One study investigated ivermectin for prevention of SARS-CoV-2 infection. Eight studies had an open-label design, six were double-blind and placebo-controlled. Of the 41 study results contributed by included studies, about one third were at overall high risk of bias.  Ivermectin doses and treatment duration varied among included studies.  We identified 31 ongoing and 18 studies awaiting classification until publication of results or clarification of inconsistencies. Ivermectin compared to placebo or standard of care for inpatient COVID-19 treatment We are uncertain whether ivermectin compared to placebo or standard of care reduces or increases mortality (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.14 to 2.51; 2 studies, 185 participants; very low-certainty evidence) and clinical worsening up to day 28 assessed as need for invasive mechanical ventilation (IMV) (RR 0.55, 95% CI 0.11 to 2.59; 2 studies, 185 participants; very low-certainty evidence) or need for supplemental oxygen (0 participants required supplemental oxygen; 1 study, 45 participants; very low-certainty evidence), adverse events within 28 days (RR 1.21, 95% CI 0.50 to 2.97; 1 study, 152 participants; very low-certainty evidence), and viral clearance at day seven (RR 1.82, 95% CI 0.51 to 6.48; 2 studies, 159 participants; very low-certainty evidence). Ivermectin may have little or no effect compared to placebo or standard of care on clinical improvement up to 28 days (RR 1.03, 95% CI 0.78 to 1.35; 1 study; 73 participants; low-certainty evidence) and duration of hospitalization (mean difference (MD) -0.10 days, 95% CI -2.43 to 2.23; 1 study; 45 participants; low-certainty evidence). No study reported quality of life up to 28 days. Ivermectin compared to placebo or standard of care for outpatient COVID-19 treatment We are uncertain whether ivermectin compared to placebo or standard of care reduces or increases mortality up to 28 days (RR 0.33, 95% CI 0.01 to 8.05; 2 studies, 422 participants; very low-certainty evidence) and clinical worsening up to 14 days assessed as need for IMV (RR 2.97, 95% CI 0.12 to 72.47; 1 study, 398 participants; very low-certainty evidence) or non-IMV or high flow oxygen requirement (0 participants required non-IMV or high flow; 1 study, 398 participants; very low-certainty evidence). We are uncertain whether ivermectin compared to placebo reduces or increases viral clearance at seven days (RR 3.00, 95% CI 0.13 to 67.06; 1 study, 24 participants; low-certainty evidence). Ivermectin may have little or no effect compared to placebo or standard of care on the number of participants with symptoms resolved up to 14 days (RR 1.04, 95% CI 0.89 to 1.21; 1 study, 398 participants; low-certainty evidence) and adverse events within 28 days (RR 0.95, 95% CI 0.86 to 1.05; 2 studies, 422 participants; low-certainty evidence). None of the studies reporting duration of symptoms were eligible for primary analysis. No study reported hospital admission or quality of life up to 14 days. Ivermectin compared to no treatment for prevention of SARS-CoV-2 infection We found one study. Mortality up to 28 days was the only outcome eligible for primary analysis. We are uncertain whether ivermectin reduces or increases mortality compared to no treatment (0 participants died; 1 study, 304 participants; very low-certainty evidence). The study reported results for development of COVID-19 symptoms and adverse events up to 14 days that were included in a secondary analysis due to high risk of bias. No study reported SARS-CoV-2 infection, hospital admission, and quality of life up to 14 days.

AUTHORS' CONCLUSIONS

Based on the current very low- to low-certainty evidence, we are uncertain about the efficacy and safety of ivermectin used to treat or prevent COVID-19. The completed studies are small and few are considered high quality. Several studies are underway that may produce clearer answers in review updates. Overall, the reliable evidence available does not support the use ivermectin for treatment or prevention of COVID-19 outside of well-designed randomized trials.

Comprehensive Cardiotoxicity Assessment of COVID-19 Treatments Using Human Induced Pluripotent Stem Cell-derived Cardiomyocytes

Coronavirus disease 2019 (COVID-19) continues to spread across the globe, with numerous clinical trials underway seeking to develop and test effective COVID-19 therapies, including remdesivir. Several ongoing studies have reported hydroxychloroquine-induced cardiotoxicity, including development of torsade de pointes (TdP). Meanwhile, human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) are expected to serve as a tool for assessing drug-induced cardiotoxicity, such as TdP and contraction impairment. However, the cardiotoxicity of COVID-19 treatments has not been fully assessed using hiPSC-CMs. In the present study, we focused on drug repurposing with various modes of actions and examined the TdP risk associated with COVID-19 treatments using field potential using multi-electrode array (MEA) system and motion analysis with hiPSC-CMs. Hydroxychloroquine induced early after depolarization, while remdesivir, favipiravir, camostat and ivermectin had little effect on field potentials. We then analyzed electromechanical window (EMw), which is defined as the difference between field potential and contraction-relaxation durations. Hydroxychloroquine decreased EMw of hiPSC-CMs in a concentration-dependent manner. In contrast, other drugs have little effect. Our data suggest that hydroxychloroquine has proarrhythmic risk and other drugs have low proarrhythmic risk. Thus, hiPSC-CMs represent a useful tool for assessing the comprehensive cardiotoxicity caused by COVID-19 treatments in non-clinical settings.

The time to offer treatments for COVID-19

Background: COVID-19 has several overlapping phases. Treatments to date have focused on the late stage of disease in hospital. Yet, the pandemic is by propagated by the viral phase in out-patients. The current public health strategy relies solely on vaccines to prevent disease.Methods: We searched the major national registries, pubmed.org, and the preprint servers for all ongoing, completed and published trial results.Results: As of 2/15/2021, we found 111 publications reporting findings on 14 classes of agents, and 9 vaccines. There were 62 randomized controlled studies, the rest retrospective observational analyses. Only 21 publications dealt with outpatient care. Remdesivir and high titer convalescent plasma have emergency use authorization for hospitalized patients in the U.S.A. There is also support for glucocorticoid treatment of the COVID-19 respiratory distress syndrome. Monoclonal antibodies are authorized for outpatients, but supply is inadequate to treat all at time of diagnosis. Favipiravir, ivermectin, and interferons are approved in certain countries.Expert Opinion: Vaccines and antibodies are highly antigen specific, and new SARS-Cov-2 variants are appearing. We call on public health authorities to authorize treatments with known low-risk and possible benefit for outpatients in parallel with universal vaccination.

Efficacy of Generalized Face Masking Mandates

This commentary discusses if targeted uses of face masks may provide better results than generalized face masks mandates to limit the spread of Covid-19. The study is based on a literature review, as well as the analysis of cases and fatalities of different countries adopting different mask mandates. Before the Covid-19 emergency, the literature was consistently against generalized masking for cold and flu viruses. The latest literature for Covid-19 infection is opposite mostly supportive for generalized masking, even if contrarian works exist. The Covid-19 recommendations are not based on randomized controlled trials of healthy individuals wearing or not masks, differentiating in between closed or open spaces. Countries that did not mandate face masks have not performed worse for the number of cases and fatalities than countries that adopted generalized face masking policies during the Covid-19 emergency. Face masks help against Covid-19 infection but also have downfalls. Their benefits are overestimated, while their risks are underestimated. Masks can block the larger droplets exhaled by an infected wearer, protecting the healthy from viral exposure, but their ability to filter out viruses is variable and generally poor especially in reused cloth masks worn by the public. New surgical masks should be used in crowded spaces especially indoors, preferring distancing without masks outdoor. There are serious unintended consequences from wearing face masks improperly and for too long that must be accounted for. There could be more advantages from targeted rather than generalized uses of only surgical face masks.

A scoping review of the pathophysiology of COVID-19

COVID-19 is a highly heterogeneous and complex medical disorder; indeed, severe COVID-19 is probably amongst the most complex of medical conditions known to medical science. While enormous strides have been made in understanding the molecular pathways involved in patients infected with coronaviruses an overarching and comprehensive understanding of the pathogenesis of COVID-19 is lacking. Such an understanding is essential in the formulation of effective prophylactic and treatment strategies. Based on clinical, proteomic, and genomic studies as well as autopsy data severe COVID-19 disease can be considered to be the connection of three basic pathologic processes, namely a pulmonary macrophage activation syndrome with uncontrolled inflammation, a complement-mediated endothelialitis together with a procoagulant state with a thrombotic microangiopathy. In addition, platelet activation with the release of serotonin and the activation and degranulation of mast cells contributes to the hyper-inflammatory state. Auto-antibodies have been demonstrated in a large number of hospitalized patients which adds to the end-organ damage and pro-thrombotic state. This paper provides a clinical overview of the major pathogenetic mechanism leading to severe COVID-19 disease.