Ivermectin and mortality in patients with COVID-19: A systematic review, meta-analysis, and meta-regression of randomized controlled trials

Effectiveness of Drug Repurposing and Natural Products Against SARS-CoV-2: A Comprehensive Review

The Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) is a betacoronavirus responsible for the COVID-19 pandemic, causing respiratory disorders, and even death in some individuals, if not appropriately treated in time. To face the pandemic, preventive measures have been taken against contagions and the application of vaccines to prevent severe disease and death cases. For the COVID-19 treatment, antiviral, antiparasitic, anticoagulant and other drugs have been reused due to limited specific medicaments for the disease. Drug repurposing is an emerging strategy with therapies that have already tested safe in humans. One promising alternative for systematic experimental screening of a vast pool of compounds is computational drug repurposing (in silico assay). Using these tools, new uses for approved drugs such as chloroquine, hydroxychloroquine, ivermectin, zidovudine, ribavirin, lamivudine, remdesivir, lopinavir and tenofovir/emtricitabine have been conducted, showing effectiveness in vitro and in silico against SARS-CoV-2 and some of these, also in clinical trials. Additionally, therapeutic options have been sought in natural products (terpenoids, alkaloids, saponins and phenolics) with promising in vitro and in silico results for use in COVID-19 disease. Among these, the most studied are resveratrol, quercetin, hesperidin, curcumin, myricetin and betulinic acid, which were proposed as SARS-CoV-2 inhibitors. Among the drugs reused to control the SARS-CoV2, better results have been observed for remdesivir in hospitalized patients and outpatients. Regarding natural products, resveratrol, curcumin, and quercetin have demonstrated in vitro antiviral activity against SARS-CoV-2 and in vivo, a nebulized formulation has demonstrated to alleviate the respiratory symptoms of COVID-19. This review shows the evidence of drug repurposing efficacy and the potential use of natural products as a treatment for COVID-19. For this, a search was carried out in PubMed, SciELO and ScienceDirect databases for articles about drugs approved or under study and natural compounds recognized for their antiviral activity against SARS-CoV-2.

Comparative Efficacy of Endogenous Stem Cells Recruiting Hydrogels and Stem Cell-loaded Hydrogels in Knee Cartilage Regeneration: A Meta- analysis

BACKGROUND

Cartilage defects remain a challenge in diseases such as osteoarthritis (OA) and fractures. Scientists have explored the use of hydrogels in conjunction with stem cell technology as a tissue engineering method to treat cartilage defects in joints. In recent years, research into hydrogels containing stem cell technology for cartilage repair has mainly focused on two categories: stem cell-loaded hydrogels and endogenous stem cell recruiting hydrogels. The latter, utilizing cell-free products, represents a novel concept with several advantages, including easier dose standardization, wider sources, and simpler storage. This meta-analysis aims to assess and compare the therapeutic effects of endogenous stem cell recruiting hydrogels and stem cell-loaded hydrogels in promoting articular cartilage regeneration in animal models, with the goal of exploring endogenous stem cell recruiting hydrogels as a promising replacement therapy for knee cartilage regeneration in preclinical animal studies.

METHODS

We systematically searched PubMed, Web of Science, Cochrane Library, and Embase until January 2023 using key words related to stem cells, cartilage regeneration and hydrogel. A random-effects meta-analysis was performed to evaluate the therapeutic effect on newborn cartilage formation. Stratified analyses were also carried out by independently classifying trials according to similar characteristics. The level of evidence was determined using the GRADE method.

RESULTS

Twenty-eight studies satisfied the inclusion criteria. Comprehensive analyses revealed that the use of endogenous stem cell recruiting hydrogels significantly promoted the formation of new cartilage in the knee joint, as evidenced by the histological score (3.77, 95% CI 2.40, 5.15; p < 0.0001) and the International Cartilage Repair Society (ICRS) macroscopic score (3.00, 95% CI 1.83, 4.18; p = 0.04), compared with the control group. The stem cell-loaded hydrogels also increased cartilage regeneration in the knee with the histological score (3.13, 95% CI 2.22, 4.04; p = 0.02) and the ICRS macroscopic score (2.49, 95% CI 1.16, 3.82; p = 0.03) in comparison to the control. Significant heterogeneity between studies was observed, and further stratified and sensitivity analyses identified the transplant site and modelling method as the sources of heterogeneity.

CONCLUSION

The current study indicates that both endogenous stem cell recruiting hydrogels and stem cell loaded hydrogels can effectively promote knee joint cartilage regeneration in animal trials.

Results of a systematic review and meta-analysis of early studies on ivermectin in SARS-CoV-2 infection

Ivermectin, an antiparasitic drug, has been repurposed for COVID-19 treatment during the SARS-CoV-2 pandemic. Although its antiviral efficacy was confirmed early in vitro and in preclinical studies, its clinical efficacy remained ambiguous. Our purpose was to assess the efficacy of ivermectin in terms of time to viral clearance based on the meta-analysis of available clinical trials at the closing date of the data search period, one year after the start of the pandemic. This meta-analysis was reported by following the PRISMA guidelines and by using the PICO format for formulating the question. The study protocol was registered on PROSPERO. Embase, MEDLINE (via PubMed), Cochrane Central Register of Controlled Trials (CENTRAL), bioRvix, and medRvix were searched for human studies of patients receiving ivermectin therapy with control groups. No language or publication status restrictions were applied. The search ended on 1/31/2021 exactly one year after WHO declared the public health emergency on novel coronavirus. The meta-analysis of three trials involving 382 patients revealed that the mean time to viral clearance was 5.74 days shorter in case of ivermectin treatment compared to the control groups [WMD = -5.74, 95% CI (-11.1, -0.39), p = 0.036]. Ivermectin has significantly reduced the time to viral clearance in mild to moderate COVID-19 diseases compared to control groups. However, more eligible studies are needed for analysis to increase the quality of evidence of ivermectin use in COVID-19.

Patch-clamp studies and cell viability assays suggest a distinct site for viroporin inhibitors on the E protein of SARS-CoV-2

BACKGROUND

SARS-CoV-2 has caused a worldwide pandemic since December 2019 and the search for pharmaceutical targets against COVID-19 remains an important challenge. Here, we studied the envelope protein E of SARS-CoV and SARS-CoV-2, a highly conserved 75-76 amino acid viroporin that is crucial for virus assembly and release. E protein channels were recombinantly expressed in HEK293 cells, a membrane-directing signal peptide ensured transfer to the plasma membrane.

METHODS

Viroporin channel activity of both E proteins was investigated using patch-clamp electrophysiology in combination with a cell viability assay. We verified inhibition by classical viroporin inhibitors amantadine, rimantadine and 5-(N,N-hexamethylene)-amiloride, and tested four ivermectin derivatives.

RESULTS

Classical inhibitors showed potent activity in patch-clamp recordings and viability assays. In contrast, ivermectin and milbemycin inhibited the E channel in patch-clamp recordings but displayed only moderate activity on the E protein in the cell viability assay, which is also sensitive to general cytotoxic activity of the tested compounds. Nemadectin and ivermectin aglycon were inactive. All ivermectin derivatives were cytotoxic at concentrations > 5 µM, i.e. below the level required for E protein inhibition.

CONCLUSIONS

This study demonstrates direct inhibition of the SARS-CoV-2 E protein by classical viroporin inhibitors. Ivermectin and milbemycin inhibit the E protein channel but their cytotoxicity argues against clinical application.

An Historical Causal-Chain Theory of Conceptions of Intelligence

Lurking behind every conception of intelligence—whether an implicit (folk) or explicit (expert-generated) conception—is an underlying theory of meaning that specifies the form the theory of intelligence does and, indeed, can take. These underlying theories of meaning become presuppositions for the conception’s form. The theories of meaning have different origins—for example, psycholinguistic, philosophical, and anthropological. This essay reviews the different underlying theories of meaning and proposes a new historical causal-chain theory of conceptions of intelligence. The underlying theories of meaning affect the flexibility and modifiability of laypersons’ (implicit) and experts’ (explicit) conceptions of intelligence. As a result, these historical causal chains have profound but largely invisible effects on societies.

A twisting tale of misinformation: should ivermectin be approved as a treatment for COVID-19 disease?

This editorial examines what has caused the evidence around ivermectin to be so controversial, provides a brief analysis of recently published evidence, and highlights why it is important to learn lessons from ivermectin for future re-purposed drugs.

Model exploration for discovering COVID-19 targeted traditional Chinese medicine

In terms of treatment, a particularly targeted drug is needed to combat the COVID-19 pandemic. Although there are currently no specific drugs for COVID-19, traditional Chinese medicine(TCM) is clearly effective. It is recommended that through data analysis and mining of TCM cases (expert experience) and population evidence (RCT and cohort studies), core prescriptions for various efficacy can be obtained. Starting from a multidimensional model of regulating immunity, improving inflammation, and protecting multiple organs, this paper constructs a multidimensional model of targeted drug discovery, integrating molecular, cellular, and animal efficacy evaluation. Through functional activity testing, biophysical detection of compound binding to target proteins, multidimensional pharmacodynamic evaluation systems of cells (Vero E6, Vero, Vero81, Huh7, and caca2) and animals (mice infected with the new coronavirus, rhesus macaques, and hamsters), the effectiveness of effective preparations was evaluated, and various efficacy effects including lung moisturizing, dehumidification and detoxification were obtained. Using modern technology, it is now possible to understand how the immune system is controlled, how inflammation is reduced, and how various organs are protected. Complete early drug characterization and finally obtain effective targeted TCM. This article provides a demonstration resource for the development of new drugs specifically for TCM.

COVID-19 Case Management Outcomes Amongst Diabetes and Hypertensive Patients in the United Arab Emirates: A Prospective Study

The global pandemic of the novel Coronavirus infection 2019 (COVID-19) challenged the care of comorbid patients. The risk imposed by COVID-19 on diabetes patients is multisystemic, exponential, and involves glucose dysregulation. The increased burden for diabetes patients infected with COVID-19 is substantial in countries with a high prevalence of diabetics, such as the United Arab Emirates (UAE). This study aims to explore the prevalence of diabetes, clinical characteristic, and outcomes of patients admitted for COVID-19 treatment with or without a concurrent preadmission diagnosis of diabetes. A prospective study was performed on 1199 adults admitted with confirmed COVID-19 from December 2020 to April 2021 to a single hospital in the UAE. The study compared the demographics, clinical characteristics, and outcomes in COVID-19-infected patients with diabetes to patients without diabetes. The study endpoints include the development of new-onset diabetes, admission to ICU, trends in the blood glucose levels, and death. A total of 1199 patients (390 with diabetes) were included in the study. A diabetes prevalence was detected among 9.8% of the study population. Among the diabetes group, 10.8% were morbidly obese, 65.4% had associated hypertension, and 18.9% had coronary artery disease. Diabetes patients showed higher rates of ICU admission (11.1% vs. 7.1%), NIV requirement (9.6% vs. 6.4%), and intubation (5.45% vs. 2%) compared to the non-diabetes group. Advanced age was a predictor of a worsening COVID-19 course, while diabetes (p < 0.050) and hypertension (p < 0.025) were significant predictors of death from COVID-19. Nearly three-fourths (284 (73.4%)) of the diabetic patients developed worsened hyperglycemia as compared to one-fifth (171 (20.9%)) of the nondiabetic patients. New-onset diabetes was detected in 9.8% of COVID-19 patients. COVID-19 severity is higher in the presence of diabetes and is associated with worsening hyperglycemia and poor clinical outcomes. Preexisting hypertension is a predictor of COVID-19 severity and death.

Central Effects of Ivermectin in Alleviation of Covid-19-induced Dysauto-nomia

Covid-19 may be associated with various neurological disorders, including dysautonomia, a dysfunction of the autonomic nervous system (ANS). In Covid-19, hypoxia, immunoinflammatory abnormality, and deregulation of the renin-angiotensin system (RAS) may increase sympathetic discharge with dysautonomia development. Direct SARS-CoV-2 cytopathic effects and associated inflammatory reaction may lead to neuroinflammation, affecting different parts of the central nervous system (CNS), including the autonomic center in the hypothalamus, causing dysautonomia. High circulating AngII, hypoxia, oxidative stress, high pro-inflammatory cytokines, and emotional stress can also provoke autonomic deregulation and high sympathetic outflow with the development of the sympathetic storm. During SARS-CoV-2 infection with neuro-invasion, GABA-ergic neurons and nicotinic acetylcholine receptor (nAChR) are inhibited in the hypothalamic pre-sympathetic neurons leading to sympathetic storm and dysautonomia. Different therapeutic modalities are applied to treat SARS-CoV-2 infection, like antiviral and anti-inflammatory drugs. Ivermectin (IVM) is a robust repurposed drug widely used to prevent and manage mild-moderate Covid-19. IVM activates both GABA-ergic neurons and nAChRs to mitigate SARS-CoV-2 infection- induced dysautonomia. Therefore, in this brief report, we try to identify the potential role of IVM in managing Covid-19-induced dysautonomia.

Ivermectin: A Controversial Focal Point during the COVID-19 Pandemic

The SARS-CoV-2 pandemic has confirmed the apocalyptic predictions that virologists have been making for several decades. The challenge the world is facing is that of trying to find a possible treatment, and a viable and expedient option for addressing this challenge is the repurposing of drugs. However, in some cases, although these drugs are approved for use in humans, the mechanisms of action involved are unknown. In this sense, to justify its therapeutic application to a new disease, it is ideal, but not necessary, to know the basic mechanisms of action involved in a drug's biological effects. This review compiled the available information regarding the various effects attributed to Ivermectin. The controversy over its use for the treatment of COVID-19 is demonstrated by this report that considers the proposal unfeasible because the therapeutic doses proposed to achieve this effect cannot be achieved. However, due to the urgent need to find a treatment, an exhaustive and impartial review is necessary in order to integrate the knowledge that exists, to date, of the possible mechanisms through which the treatment may be helpful in defining safe doses and schedules of Ivermectin.

The effect of ivermectin on the viral load and culture viability in early treatment of nonhospitalized patients with mild COVID-19 - a double-blind, randomized placebo-controlled trial

OBJECTIVES

Ivermectin, an antiparasitic agent, also has antiviral properties. In this study, we aimed to assess whether ivermectin has anti-SARS-CoV-2 activity.

METHODS

In this double-blinded trial, we compared patients receiving ivermectin for 3 days versus placebo in nonhospitalized adult patients with COVID-19. A reverse transcriptase-polymerase chain reaction from a nasopharyngeal swab was obtained at recruitment and every 2 days for at least 6 days. The primary endpoint was a reduction of viral load on the sixth day as reflected by cycle threshold level >30 (noninfectious level). The primary outcome was supported by the determination of viral-culture viability.

RESULTS

Of 867 patients screened, 89 were ultimately evaluated per-protocol (47 ivermectin and 42 placeboes). On day 6, the odds ratio (OR) was 2.62 (95% confidence interval [CI]: 1.09-6.31) in the ivermectin arm, reaching the endpoint. In a multivariable logistic regression model, the odds of a negative test on day 6 were 2.28 times higher in the ivermectin group but reached significance only on day 8 (OR 3.70; 95% CI: 1.19-11.49, P = 0.02). Culture viability on days 2 to 6 was positive in 13.0% (3/23) of ivermectin samples versus 48.2% (14/29) in the placebo group (P = 0.008).

CONCLUSION

There were lower viral loads and less viable cultures in the ivermectin group, which shows its anti-SARS-CoV-2 activity. It could reduce transmission in these patients and encourage further studies with this drug.

Ivermectin under scrutiny: a systematic review and meta-analysis of efficacy and possible sources of controversies in COVID-19 patients

BACKGROUND

We conducted a systematic review and meta-analysis to evaluate the efficacy of ivermectin for COVID-19 patients based on current peer-reviewed RCTs and to address disputes over the existing evidence.

METHODS

MEDLINE (Pubmed), Scopus, Web of Science, Cochrane library, Google scholar and Clinicaltrials.gov were searched for RCTs assessing the efficacy of Ivermectin up to 20 February 2022. A systematic review and meta-analysis of studies was performed based on the PRISMA 2020 statement criteria.

RESULTS

19 and 17 studies were included in this systematic review and meta-analysis, respectively. There was no significant difference in progression to severe disease (log OR - 0.27 [95% CI - 0.61 to 0.08], I2 = 42.29%), negative RT-PCR (log OR 0.25 [95% CI - 0.18-0.68], I2 = 58.73%), recovery (log OR 0.11 [95% CI - 0.22-0.45], I2 = 13.84%), duration of hospitalization (SMD - 0.40 [95% CI - 0.85-0.06], I2 = 88.90%), time to negative RT-PCR (SMD - 0.36 [95% CI - 0.89-0.17], I2 = 46.2%), and viral load (SMD -0.17 [95% CI -0.45 to 0.12], I^2 = 0%). It is worth noting that, based on low-certainty evidence, ivermectin may possibly reduce mortality (log OR - 0.67 [95% CI - 1.20 to - 0.13], I2 = 28.96%). However, studies with a higher risk of bias were more likely to indicate positive effects on the efficacy of this drug, according to our subgroup analyses based on study quality.

CONCLUSION

Ivermectin did not have any significant effect on outcomes of COVID-19 patients and as WHO recommends, use of ivermectin should be limited to clinical trials.

Effect of Early Treatment with Ivermectin among Patients with Covid-19

BACKGROUND

The efficacy of ivermectin in preventing hospitalization or extended observation in an emergency setting among outpatients with acutely symptomatic coronavirus disease 2019 (Covid-19), the disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is unclear.

METHODS

We conducted a double-blind, randomized, placebo-controlled, adaptive platform trial involving symptomatic SARS-CoV-2-positive adults recruited from 12 public health clinics in Brazil. Patients who had had symptoms of Covid-19 for up to 7 days and had at least one risk factor for disease progression were randomly assigned to receive ivermectin (400 μg per kilogram of body weight) once daily for 3 days or placebo. (The trial also involved other interventions that are not reported here.) The primary composite outcome was hospitalization due to Covid-19 within 28 days after randomization or an emergency department visit due to clinical worsening of Covid-19 (defined as the participant remaining under observation for >6 hours) within 28 days after randomization.

RESULTS

A total of 3515 patients were randomly assigned to receive ivermectin (679 patients), placebo (679), or another intervention (2157). Overall, 100 patients (14.7%) in the ivermectin group had a primary-outcome event, as compared with 111 (16.3%) in the placebo group (relative risk, 0.90; 95% Bayesian credible interval, 0.70 to 1.16). Of the 211 primary-outcome events, 171 (81.0%) were hospital admissions. Findings were similar to the primary analysis in a modified intention-to-treat analysis that included only patients who received at least one dose of ivermectin or placebo (relative risk, 0.89; 95% Bayesian credible interval, 0.69 to 1.15) and in a per-protocol analysis that included only patients who reported 100% adherence to the assigned regimen (relative risk, 0.94; 95% Bayesian credible interval, 0.67 to 1.35). There were no significant effects of ivermectin use on secondary outcomes or adverse events.

CONCLUSIONS

Treatment with ivermectin did not result in a lower incidence of medical admission to a hospital due to progression of Covid-19 or of prolonged emergency department observation among outpatients with an early diagnosis of Covid-19. (Funded by FastGrants and the Rainwater Charitable Foundation; TOGETHER ClinicalTrials.gov number, NCT04727424.).

Ivermectin and the Integrity of Healthcare Evidence During COVID-19

The COVID-19 pandemic has been characterized by a lack of clear evidence to guide healthcare professionals, the public and policymakers. The resulting uncertainty, coupled with changing guidelines as additional evidence became available, added to the stress and anxiety reported by decision-makers. Research results are key to providing evidence to guide healthcare decisions. Important questions have arisen about whether various interventions are safe and effective. The evidence found guides those making treatment decisions, and influences those selecting interventions for further evaluation in research studies. As the COVID-19 pandemic intensified, the effectiveness and safety of many pharmaceuticals was queried. Ivermectin will be used to explore the ethics of how healthcare evidence must be critically appraised, even, or especially, during a pandemic. This drug is alleged to be effective in treating COVID-19, with various studies and systematic reviews finding supportive evidence. Some of these have now been linked to concerns about fraud or poor research reporting. This article will focus on the scientific literature and how apparently fraudulent studies were published and influenced treatment decisions, on-going research and public health guidelines. Research evidence is critical during emergencies like pandemics, but urgency should not overtake ethical responsibilities to critically appraise (or evaluate) studies as they become available. These responsibilities apply in various ways to editors, peer-reviewers, news media reporters, and those making treatment decisions, including clinicians, policymakers and the general public. While research article authors have the primary ethical responsibility to reject fraudulent or inaccurate claims, the readers of health research must carefully evaluate all publications. To detect and reject fraudulent healthcare claims, readers need critical appraisal skills that match their level of engagement with those articles. The core principles of critical appraisal will be described in the article, and how they can be adapted for different types of readers. Exemplar tools that develop critical appraisal skills will be noted, with reviews of ivermectin's efficacy explored as examples. As stakeholders in healthcare evidence are increasingly able to identify well-conducted and ethical research they will simultaneously be able to spot and reject fraudulent reports and prevent them from influencing healthcare decisions.

Ofeleein i mi Vlaptin-Volume II: Immunity Following Infection or mRNA Vaccination, Drug Therapies and Non-Pharmacological Management at Post-Two Years SARS-CoV-2 Pandemic

The persistence of the coronavirus disease 2019 (COVID-19) pandemic has triggered research into limiting transmission, morbidity and mortality, thus warranting a comprehensive approach to guide balanced healthcare policies with respect to people's physical and mental health. The mainstay priority during COVID-19 is to achieve widespread immunity, which could be established through natural contact or vaccination. Deep knowledge of the immune response combined with recent specific data indicates the potential inferiority of induced immunity against infection. Moreover, the prevention of transmission has been founded on general non-pharmacological measures of protection, albeit debate exists considering their efficacy and, among other issues, their socio-psychological burden. The second line of defense is engaged after infection and is supported by a plethora of studied agents, such as antibiotics, steroids and non-steroid anti-inflammatory drugs, antiviral medications and other biological agents that have been proposed, though variability in terms of benefits and adverse events has not allowed distinct solutions, albeit certain treatments might have a role in prevention and/or treatment of the disease. This narrative review summarizes the existing literature on the advantages and weaknesses of current COVID-19 management measures, thus underlining the necessity of acting based on the classical principle of "ofeleein i mi vlaptin", that is, to help or not to harm.

High dose ivermectin for the early treatment of COVID-19 (COVER study): a randomised, double-blind, multicentre, phase II, dose-finding, proof of concept clinical trial

High concentrations of ivermectin demonstrated antiviral activity against SARS-CoV-2 in vitro. The aim of this study was to assess the safety and efficacy of high-dose ivermectin in reducing viral load in individuals with early SARS-CoV-2 infection. This was a randomised, double-blind, multicentre, phase II, dose-finding, proof-of-concept clinical trial. Participants were adults recently diagnosed with asymptomatic/oligosymptomatic SARS-CoV-2 infection. Exclusion criteria were: pregnant or lactating women; CNS disease; dialysis; severe medical condition with prognosis <6 months; warfarin treatment; and antiviral/chloroquine phosphate/hydroxychloroquine treatment. Participants were assigned (ratio 1:1:1) according to a randomised permuted block procedure to one of the following arms: placebo (arm A); single-dose ivermectin 600 μg/kg plus placebo for 5 days (arm B); and single-dose ivermectin 1200 μg/kg for 5 days (arm C). Primary outcomes were serious adverse drug reactions (SADRs) and change in viral load at Day 7. From 31 July 2020 to 26 May 2021, 32 participants were randomised to arm A, 29 to arm B and 32 to arm C. Recruitment was stopped on 10 June because of a dramatic drop in cases. The safety analysis included 89 participants and the change in viral load was calculated in 87 participants. No SADRs were registered. Mean (S.D.) log₁₀ viral load reduction was 2.9 (1.6) in arm C, 2.5 (2.2) in arm B and 2.0 (2.1) in arm A, with no significant differences (P = 0.099 and 0.122 for C vs. A and B vs. A, respectively). High-dose ivermectin was safe but did not show efficacy to reduce viral load.

Ivermectin administration is associated with lower gastrointestinal complications and greater ventilator-free days in ventilated patients with COVID-19: A propensity score analysis

Introduction

COVID-19 patients have been reported to have digestive symptoms with poor outcome. Ivermectin, an antiparasitic drug, has been used in COVID-19 patients. The objective of this study was to evaluate whether ivermectin has effects on gastrointestinal complications and ventilator-free days in ventilated patients with COVID-19.

Methods

COVID-19 patients who were mechanically ventilated in the ICU were included in this study. The ventilated patients who received ivermectin within 3 days after admission were assigned to the Ivermectin group, and the others were assigned to the Control group. Patients in the Ivermectin group received ivermectin 200 μg/kg via nasal tube. The incidence of gastrointestinal complications and ventilator-free days within 4 weeks from admission were evaluated as clinical outcomes using a propensity score with the inverse probability weighting method.

Results

We included 88 patients in this study, of whom 39 patients were classified into the Ivermectin group, and 49 patients were classified into the Control group. The hazard ratio for gastrointestinal complications in the Ivermectin group as compared with the Control group was 0.221 (95% confidence interval [CI], 0.057 to 0.855; p = 0.029) in a Cox proportional-hazard regression model. The odds ratio for ventilator-free days as compared with the Control group was 1.920 (95% CI, 1.076 to 3.425; p = 0.027) in a proportional odds logistic regression model.

Conclusions

Ivermectin improved gastrointestinal complications and the number of ventilator-free days in severe COVID-19 patients undergoing mechanical ventilation. Prevention of gastrointestinal symptoms by SARS-Cov-2 might be associated with COVID-19 outcome.

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.

An update on drugs with therapeutic potential for SARS-CoV-2 (COVID-19) treatment

The COVID-19 pandemic is one of the greatest threats to human health in the 21st century with more than 257 million cases and over 5.17 million deaths reported worldwide (as of November 23, 2021. Various agents were initially proclaimed to be effective against SARS-CoV-2, the etiological agent of COVID-19. Hydroxychloroquine, lopinavir/ritonavir, and ribavirin are all examples of therapeutic agents, whose efficacy against COVID-19 was later disproved. Meanwhile, concentrated efforts of researchers and clinicians worldwide have led to the identification of novel therapeutic options to control the disease including PAXLOVID™ (PF-07321332). Although COVID-19 cases are currently treated using a comprehensive approach of anticoagulants, oxygen, and antibiotics, the novel Pfizer agent PAXLOVID™ (PF-07321332), an investigational COVID-19 oral antiviral candidate, significantly reduced hospitalization time and death rates, based on an interim analysis of the phase 2/3 EPIC-HR (Evaluation of Protease Inhibition for COVID-19 in High-Risk Patients) randomized, double-blind study of non-hospitalized adult patients with COVID-19, who are at high risk of progressing to severe illness. The scheduled interim analysis demonstrated an 89 % reduction in risk of COVID-19-related hospitalization or death from any cause compared to placebo in patients treated within three days of symptom onset (primary endpoint). However, there still exists a great need for the development of additional treatments, as the recommended therapeutic options are insufficient in many cases. Thus far, mRNA and vector vaccines appear to be the most effective modalities to control the pandemic. In the current review, we provide an update on the progress that has been made since April 2020 in clinical trials concerning the effectiveness of therapies available to combat COVID-19. We focus on currently recommended therapeutic agents, including steroids, various monoclonal antibodies, remdesivir, baricitinib, anticoagulants and PAXLOVID™ summarizing the latest original studies and meta-analyses. Moreover, we aim to discuss other currently and previously studied agents targeting COVID-19 that either show no or only limited therapeutic activity. The results of recent studies report that hydroxychloroquine and convalescent plasma demonstrate no efficacy against SARS-CoV-2 infection. Lastly, we summarize the studies on various drugs with incoherent or insufficient data concerning their effectiveness, such as amantadine, ivermectin, or niclosamide.

Harnessing autophagy to fight SARS-CoV-2: An update in view of recent drug development efforts

Drug repurposing is an attractive option for identifying new treatment strategies, in particular in extraordinary situations of urgent need such as the current coronavirus disease 2019 (Covid-19) pandemic. Recently, the World Health Organization announced testing of three drugs as potential Covid-19 therapeutics that are known for their dampening effect on the immune system. Thus, the underlying concept of selecting these drugs is to temper the potentially life-threatening overshooting of the immune system reacting to severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection. This viewpoint discusses the possibility that the impact of these and other drugs on autophagy contributes to their therapeutic effect by hampering the SARS-CoV-2 life cycle.