Lack of efficacy of standard doses of ivermectin in severe COVID-19 patients

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.

A comprehensive review on pharmacologic agents, immunotherapies and supportive therapeutics for COVID-19

The emergence of coronavirus disease 2019 (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has affected many countries throughout the world. As urgency is a necessity, most efforts have focused on identifying small molecule drugs that can be repurposed for use as anti-SARS-CoV-2 agents. Although several drug candidates have been identified using in silico method and in vitro studies, most of these drugs require the support of in vivo data before they can be considered for clinical trials. Several drugs are considered promising therapeutic agents for COVID-19. In addition to the direct-acting antiviral drugs, supportive therapies including traditional Chinese medicine, immunotherapies, immunomodulators, and nutritional therapy could contribute a major role in treating COVID-19 patients. Some of these drugs have already been included in the treatment guidelines, recommendations, and standard operating procedures. In this article, we comprehensively review the approved and potential therapeutic drugs, immune cells-based therapies, immunomodulatory agents/drugs, herbs and plant metabolites, nutritional and dietary for COVID-19.

Ivermectin-induced bacterial gut dysbiosis does not increase susceptibility to Pseudomonas aeruginosa lung infection but exacerbates liver damage

Excessive use of medications, including the antiparasitic drug ivermectin, can lead to bacterial gut dysbiosis, an imbalance in the intestinal microbiome, which in turn may increase or decrease susceptibility to infectious processes. To better understand the effects of continuous ivermectin usage on the gut bacterial community, C57BL/6 isogenic mice were treated by gavage with ivermectin or saline. Ivermectin-induced bacterial gut dysbiosis is characterized by a decrease in Bacteroidetes, Firmicutes, Proteobacteria and Tenericutes and an increase in species of the phylum Verrucomicrobia. A pro-inflammatory immunostimulatory caecal content, as well as disruption of caecal tissue organization and liver tissue damage, was observed in mice with gut dysbiosis. However, ivermectin-induced gut dysbiosis did not lead to acute susceptibility to Pseudomonas aeruginosa lung infection: infected mice with and without gut dysbiosis showed similar rates of recovery of viable bacteria in organs, histopathology and differential cytokine expression in the lung. Therefore, an extension of liver damage was observed in ivermectin-treated and P. aeruginosa-infected mice, which was exacerbated by infection.

Understanding the widespread use of veterinary ivermectin for Chagas disease, underlying factors and implications for the COVID-19 pandemic: a convergent mixed-methods study

OBJECTIVES

Veterinary ivermectin (vet-IVM) has been used widely in Latin America against COVID-19, despite the lack of scientific evidence and potential risks. Widespread vet-IVM intake was also discovered against Chagas disease during a study in Bolivia prior to the pandemic. All vet-IVM-related data were extracted to understand this phenomenon, its extent and underlying factors and to discuss potential implications for the current pandemic.

DESIGN

A convergent mixed-methods study design including a survey, qualitative in-depth interviews (IDI) and focus group discussions (FGD).

SETTING

A cross-sectional study conducted in 2018 covering the geographic area of Monteagudo, an endemic municipality for Chagas disease.

PARTICIPANTS

A total of 669 adult household representatives from 26 communities participated in the survey, supplemented by 14 IDI and 2 FGD among patients, relatives and key informants.

RESULTS

9 IDI and 2 FGD contained narratives on vet-IVM use against Chagas disease. Five main themes emerged: (1) the extent of the vet-IVM phenomenon, (2) the perception of vet-IVM as a treatment for Chagas disease, (3) the vet-IVM market and the controversial role of stakeholders, (4) concerns about potential adverse events and (5) underlying factors of vet-IVM use against Chagas disease.In quantitative analysis, 28% of participants seropositive for Chagas disease had taken vet-IVM. Factors associated with multivariate analysis were advanced age (OR 17.01, 95 CI 1.24 to 36.55, p=0.027 for age above 60 years), the experience of someone close as information source (OR 3.13, 95 CI 1.62 to 5.02, p<0.001), seropositivity for Chagas disease (OR 3.89, 95 CI 1.39 to 6.20, p=0.005) and citing the unavailability of benznidazole as perceived healthcare barrier (OR 2.3, 95 CI 1.45 to 5.18, p=0.002). Participants with an academic education were less likely to report vet-IVM intake (OR 0.12, 95 CI 0.01 to 0.78, p=0.029).

CONCLUSIONS

Social determinants of health, the unavailability of treatment and a wonder drug image might contribute to the phenomenon of vet-IVM.

Efficacy and safety of ivermectin in the treatment of mild to moderate COVID-19 infection: a randomized, double-blind, placebo-controlled trial

Background

The emergent outbreak of coronavirus disease (COVID-19), caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), has emphasized the requirement for therapeutic opportunities to overcome this pandemic. Ivermectin is an antiparasitic drug that has shown effectiveness against various agents, including SARS-CoV-2. This study aimed to assess the efficacy of ivermectin treatment compared with the standard of care (SOC) among people with mild to moderate COVID-19 symptoms.

Methods

In this randomized, double-blind, placebo-controlled, single-center, parallel-arm, superiority trial among adult hospitalized patients with mild to moderate COVID-19, 72 patients (mean age 48.57 ± 14.80 years) were randomly assigned to either the ivermectin (n=36) or placebo (n=36) group, along with receiving standard care. We aimed to compare the negativity of reverse transcription polymerase chain reaction (RT-PCR) result at days 7 and 14 of enrolment as the primary outcome. The secondary outcomes were duration of hospitalization, frequency of clinical worsening, survival on day 28, and adverse events.

Results

At days 7 and 14, no differences were observed in the proportion of PCR-positive patients (RR 0.97 at day 7 (p=0.759) and 0.95 at day 14 (p=0.813). No significant differences were found between the groups for any of the secondary endpoints, and no adverse events were reported.

Conclusion

No difference was found in the proportion of PCR-positive cases after treatment with ivermectin compared with standard care among patients with mild to moderate COVID-19 symptoms. However, early symptomatic recovery was observed without side effects.

Trial registration

ClinicalTrials.gov NCT05076253. Registered on 8 October 2021, prospectively.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-022-06649-3.

Antiparasitic Drugs against SARS-CoV-2: A Comprehensive Literature Survey

More than two years have passed since the viral outbreak that led to the novel infectious respiratory disease COVID-19, caused by the SARS-CoV-2 coronavirus. Since then, the urgency for effective treatments resulted in unprecedented efforts to develop new vaccines and to accelerate the drug discovery pipeline, mainly through the repurposing of well-known compounds with broad antiviral effects. In particular, antiparasitic drugs historically used against human infections due to protozoa or helminth parasites have entered the main stage as a miracle cure in the fight against SARS-CoV-2. Despite having demonstrated promising anti-SARS-CoV-2 activities in vitro, conflicting results have made their translation into clinical practice more difficult than expected. Since many studies involving antiparasitic drugs are currently under investigation, the window of opportunity might be not closed yet. Here, we will review the (controversial) journey of these old antiparasitic drugs to combat the human infection caused by the novel coronavirus SARS-CoV-2.

Ivermectin for preventing and treating COVID-19

BACKGROUND

Ivermectin, an antiparasitic agent, 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 early stages of infection. Currently, evidence on ivermectin for prevention of SARS-CoV-2 infection and COVID-19 treatment is conflicting.

OBJECTIVES

To assess the efficacy and safety of ivermectin plus standard of care compared to standard of care plus/minus 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), WHO COVID-19 Global literature on coronavirus disease, and HTA database weekly to identify completed and ongoing trials without language restrictions to 16 December 2021. Additionally, we included trials with > 1000 participants up to April 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) comparing ivermectin to standard of care, placebo, or another proven intervention for treatment of people with confirmed COVID-19 diagnosis, irrespective of disease severity or treatment setting, and for prevention of SARS-CoV-2 infection. Co-interventions had to be the same in both study arms.  For this review update, we reappraised eligible trials for research integrity: only RCTs prospectively registered in a trial registry according to WHO guidelines for clinical trial registration were eligible for inclusion.

DATA COLLECTION AND ANALYSIS

We assessed RCTs for bias, using the Cochrane RoB 2 tool. We used GRADE to rate the certainty of evidence for outcomes in the following settings and populations: 1) to treat inpatients with moderate-to-severe COVID-19, 2) to treat outpatients with mild COVID-19 (outcomes: mortality, clinical worsening or improvement, (serious) adverse events, quality of life, and viral clearance), and 3) to prevent SARS-CoV-2 infection (outcomes: SARS-CoV-2 infection, development of COVID-19 symptoms, admission to hospital, mortality, adverse events and quality of life).

MAIN RESULTS

We excluded seven of the 14 trials included in the previous review version; six were not prospectively registered and one was non-randomized. This updated review includes 11 trials with 3409 participants investigating ivermectin plus standard of care compared to standard of care plus/minus placebo. No trial investigated ivermectin for prevention of infection or compared ivermectin to an intervention with proven efficacy. Five trials treated participants with moderate COVID-19 (inpatient settings); six treated mild COVID-19 (outpatient settings). Eight trials were double-blind and placebo-controlled, and three were open-label. We assessed around 50% of the trial results as low risk of bias. We identified 31 ongoing trials. In addition, there are 28 potentially eligible trials without publication of results, or with disparities in the reporting of the methods and results, held in 'awaiting classification' until the trial authors clarify questions upon request. Ivermectin for treating COVID-19 in inpatient settings with moderate-to-severe disease We are uncertain whether ivermectin plus standard of care compared to standard of care plus/minus placebo reduces or increases all-cause mortality at 28 days (risk ratio (RR) 0.60, 95% confidence interval (CI) 0.14 to 2.51; 3 trials, 230 participants; very low-certainty evidence); or clinical worsening, assessed by participants with new need for invasive mechanical ventilation or death at day 28 (RR 0.82, 95% CI 0.33 to 2.04; 2 trials, 118 participants; very low-certainty evidence); or serious adverse events during the trial period (RR 1.55, 95% CI 0.07 to 35.89; 2 trials, 197 participants; very low-certainty evidence). Ivermectin plus standard of care compared to standard of care plus placebo may have little or no effect on clinical improvement, assessed by the number of participants discharged alive at day 28 (RR 1.03, 95% CI 0.78 to 1.35; 1 trial, 73 participants; low-certainty evidence); on any adverse events during the trial period (RR 1.04, 95% CI 0.61 to 1.79; 3 trials, 228 participants; low-certainty evidence); and on viral clearance at 7 days (RR 1.12, 95% CI 0.80 to 1.58; 3 trials, 231 participants; low-certainty evidence). No trial investigated quality of life at any time point. Ivermectin for treating COVID-19 in outpatient settings with asymptomatic or mild disease Ivermectin plus standard of care compared to standard of care plus/minus placebo probably has little or no effect on all-cause mortality at day 28 (RR 0.77, 95% CI 0.47 to 1.25; 6 trials, 2860 participants; moderate-certainty evidence) and little or no effect on quality of life, measured with the PROMIS Global-10 scale (physical component mean difference (MD) 0.00, 95% CI -0.98 to 0.98; and mental component MD 0.00, 95% CI -1.08 to 1.08; 1358 participants; high-certainty evidence). Ivermectin may have little or no effect on clinical worsening, assessed by admission to hospital or death within 28 days (RR 1.09, 95% CI 0.20 to 6.02; 2 trials, 590 participants; low-certainty evidence); on clinical improvement, assessed by the number of participants with all initial symptoms resolved up to 14 days (RR 0.90, 95% CI 0.60 to 1.36; 2 trials, 478 participants; low-certainty evidence); on serious adverse events (RR 2.27, 95% CI 0.62 to 8.31; 5 trials, 1502 participants; low-certainty evidence); on any adverse events during the trial period (RR 1.24, 95% CI 0.87 to 1.76; 5 trials, 1502 participants; low-certainty evidence); and on viral clearance at day 7 compared to placebo (RR 1.01, 95% CI 0.69 to 1.48; 2 trials, 331 participants; low-certainty evidence). None of the trials reporting duration of symptoms were eligible for meta-analysis.

AUTHORS' CONCLUSIONS

For outpatients, there is currently low- to high-certainty evidence that ivermectin has no beneficial effect for people with COVID-19. Based on the very low-certainty evidence for inpatients, we are still uncertain whether ivermectin prevents death or clinical worsening or increases serious adverse events, while there is low-certainty evidence that it has no beneficial effect regarding clinical improvement, viral clearance and adverse events. No evidence is available on ivermectin to prevent SARS-CoV-2 infection. In this update, certainty of evidence increased through higher quality trials including more participants. According to this review's living approach, we will continually update our search.

Repurposing Molnupiravir for COVID-19: The Mechanisms of Antiviral Activity

Molnupiravir is a β-d-N4-hydroxycytidine-5'-isopropyl ester (NHC) compound that exerts antiviral activity against various RNA viruses such as influenza, SARS, and Ebola viruses. Thus, the repurposing of Molnupiravir has gained significant attention for combatting infection with SARS-CoV-2, the etiological agent of COVID-19. Recently, Molnupiravir was granted authorization for the treatment of mild-to-moderate COVID-19 in adults. Findings from in vitro experiments, in vivo studies and clinical trials reveal that Molnupiravir is effective against SARS-CoV-2 by inducing viral RNA mutagenesis, thereby giving rise to mutated complementary RNA strands that generate non-functional viruses. To date, the data collectively suggest that Molnupiravir possesses promising antiviral activity as well as favorable prophylactic efficacy, attributed to its effective mutagenic property of disrupting viral replication. This review discusses the mechanisms of action of Molnupiravir and highlights its clinical utility by disabling SARS-CoV-2 replication, thereby ameliorating COVID-19 severity. Despite relatively few short-term adverse effects thus far, further detailed clinical studies and long-term pharmacovigilance are needed in view of its mutagenic effects.

Therapeutic strategies to fight COVID-19: Which is the status artis?

COVID-19 is a complex disease, and many difficulties are faced today especially in the proper choice of pharmacological treatments. The role of antiviral agents for COVID-19 is still being investigated and evidence for immunomodulatory and anti-inflammatory drugs is quite conflicting, whereas the use of corticosteroids is supported by robust evidence. The use of heparins in hospitalized critically ill patients is preferred over other anticoagulants. There are conflicting data on the use of convalescent plasma and vitamin D. According to the World Health Organization (WHO), many vaccines are in Phase III clinical trials, and some of them have already received marketing approval in European countries and in the United States. In conclusion, drug repurposing has represented the main approach recently used in the treatment of patients with COVID-19. At this moment, analysis of efficacy and safety data of drugs and vaccines used in real-life context is strongly needed. LINKED ARTICLES: This article is part of a themed issue on The second wave: are we any closer to efficacious pharmacotherapy for COVID 19? (BJP 75th Anniversary). To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v179.10/issuetoc.

Antiviral Activity of Repurposing Ivermectin against a Panel of 30 Clinical SARS-CoV-2 Strains Belonging to 14 Variants

Over the past two years, several variants of SARS-CoV-2 have emerged and spread all over the world. However, infectivity, clinical severity, re-infection, virulence, transmissibility, vaccine responses and escape, and epidemiological aspects have differed between SARS-CoV-2 variants. Currently, very few treatments are recommended against SARS-CoV-2. Identification of effective drugs among repurposing FDA-approved drugs is a rapid, efficient and low-cost strategy against SARS-CoV-2. One of those drugs is ivermectin. Ivermectin is an antihelminthic agent that previously showed in vitro effects against a SARS-CoV-2 isolate (Australia/VI01/2020 isolate) with an IC50 of around 2 µM. We evaluated the in vitro activity of ivermectin on Vero E6 cells infected with 30 clinically isolated SARS-CoV-2 strains belonging to 14 different variants, and particularly 17 strains belonging to six variants of concern (VOC) (variants related to Wuhan, alpha, beta, gamma, delta and omicron). The in vitro activity of ivermectin was compared to those of chloroquine and remdesivir. Unlike chloroquine (EC50 from 4.3 ± 2.5 to 29.3 ± 5.2 µM) or remdesivir (EC50 from 0.4 ± 0.3 to 25.2 ± 9.4 µM), ivermectin showed a relatively homogeneous in vitro activity against SARS-CoV-2 regardless of the strains or variants (EC50 from 5.1 ± 0.5 to 6.7 ± 0.4 µM), except for one omicron strain (EC50 = 1.3 ± 0.5 µM). Ivermectin (No. EC50 = 219, mean EC50 = 5.7 ± 1.0 µM) was, overall, more potent in vitro than chloroquine (No. EC50 = 214, mean EC50 = 16.1 ± 9.0 µM) (p = 1.3 × 10-34) and remdesivir (No. EC50 = 201, mean EC50 = 11.9 ± 10.0 µM) (p = 1.6 × 10-13). These results should be interpreted with caution regarding the potential use of ivermectin in SARS-CoV-2-infected patients: it is difficult to translate in vitro study results into actual clinical treatment in patients.

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.

Chemoprophylaxis against COVID-19 among health-care workers using Ivermectin in low- and middle-income countries: A systematic review and meta-analysis

Coronavirus disease-2019 (COVID-19) is a novel viral infectious disease that the World Health Organization (WHO) has announced to be a pandemic. This meta-analysis was aimed at providing evidence for the use of ivermectin to prevent COVID-19 among hospital workers in low-resource countries. Medical databases including African Journals online, Google Scholar, PubMed, Cochrane library, EMBASE, COVID-19 research database (WHO), Clinicaltrials.gov, and SCOPUS were searched for studies on Ivermectin as a chemoprophylactic drug against COVID-19 among hospital personnel in settings with limited resources. Preprint servers such as bioRxiv and medRxiv as well as the gray literature were also searched. Studies adjudged to be eligible were identified using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses algorithm. Statistical analyses were done using Stata version 14.3. Seven studies were selected for the meta-analysis. The total sample size was 2652. There were two randomized controlled trials and five nonrandomized studies. Some studies dosed Ivermectin daily while some dosed it weekly. However, one of the studies dosed it monthly. The studies reported variable clinical benefits. I² statistic was 92%, and random effect model was used. The pooled odd ratio was 0.11 (95% confidence interval 0.09–0.13). This implies that 89% of the participants benefited from taking Ivermectin as a form of preexposure chemoprophylaxis. Ivermectin has a significant clinical benefit as a preventive drug against COVID-19 for hospital personnel in settings with limited resources.

Drug Combinations as a First Line of Defense against Coronaviruses and Other Emerging Viruses

The world was unprepared for coronavirus disease 2019 (COVID-19) and remains ill-equipped for future pandemics. While unprecedented strides have been made developing vaccines and treatments for COVID-19, there remains a need for highly effective and widely available regimens for ambulatory use for novel coronaviruses and other viral pathogens. We posit that a priority is to develop pan-family drug cocktails to enhance potency, limit toxicity, and avoid drug resistance. We urge cocktail development for all viruses with pandemic potential both in the short term (<1 to 2 years) and longer term with pairs of drugs in advanced clinical testing or repurposed agents approved for other indications. While significant efforts were launched against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), in vitro and in the clinic, many studies employed solo drugs and had disappointing results. Here, we review drug combination studies against SARS-CoV-2 and other viruses and introduce a model-driven approach to assess drug pairs with the highest likelihood of clinical efficacy. Where component agents lack sufficient potency, we advocate for synergistic combinations to achieve therapeutic levels. We also discuss issues that stymied therapeutic progress against COVID-19, including testing of agents with low likelihood of efficacy late in clinical disease and lack of focus on developing virologic surrogate endpoints. There is a need to expedite efficient clinical trials testing drug combinations that could be taken at home by recently infected individuals and exposed contacts as early as possible during the next pandemic, whether caused by a coronavirus or another viral pathogen. The approach herein represents a proactive plan for global viral pandemic preparedness.

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).

SARS-CoV-2, Zika viruses and mycoplasma: Structure, pathogenesis and some treatment options in these emerging viral and bacterial infectious diseases

The molecular evolution of life on earth along with changing environmental, conditions has rendered mankind susceptible to endemic and pandemic emerging infectious diseases. The effects of certain systemic viral and bacterial infections on morbidity and mortality are considered as examples of recent emerging infections. Here we will focus on three examples of infections that are important in pregnancy and early childhood: SARS-CoV-2 virus, Zika virus, and Mycoplasma species. The basic structural characteristics of these infectious agents will be examined, along with their general pathogenic mechanisms. Coronavirus infections, such as caused by the SARS-CoV-2 virus, likely evolved from zoonotic bat viruses to infect humans and cause a pandemic that has been the biggest challenge for humanity since the Spanish Flu pandemic of the early 20th century. In contrast, Zika Virus infections represent an expanding infectious threat in the context of global climate change. The relationship of these infections to pregnancy, the vertical transmission and neurological sequels make these viruses highly relevant to the topics of this special issue. Finally, mycoplasmal infections have been present before mankind evolved, but they were rarely identified as human pathogens until recently, and they are now recognized as important coinfections that are able to modify the course and prognosis of various infectious diseases and other chronic illnesses. The infectious processes caused by these intracellular microorganisms are examined as well as some general aspects of their pathogeneses, clinical presentations, and diagnoses. We will finally consider examples of treatments that have been used to reduce morbidity and mortality of these infections and discuss briefly the current status of vaccines, in particular, against the SARS-CoV-2 virus. It is important to understand some of the basic features of these emerging infectious diseases and the pathogens involved in order to better appreciate the contributions of this special issue on how infectious diseases can affect human pregnancy, fetuses and neonates.

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.

COVID-19 and Ivermectin: Potential threats associated with human use

Drugs re-purposing due to COVID-19 virus has declared a number of useful candidates for treatment and prevention of the virus. Ivermectin (IVM) has gained much popularity due to a strong background of magical applications against a broad spectrum of pathogens. The in- vitro studies of ivermectin have shown promise, the thorough clinical trials of its efficacy in the treatment and prevention of SARS-CoV-2 are still warranted. Useful strategies for analyzing projected use of IVM in human coronaviruses might be developed. It may be done by concluding ongoing clinical trials and culturing lessons from IVM usage in veterinary practice. The potential toxicity and careful dosage analyses are urgently required before declaring it as an anti-SARS-CoV-2 drug candidate. This manuscript overviews the background and potential threats associated with the off-label use of IVM as prophylactic drug or treatment option against COVID-19 virus.

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.

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.

Interactions of anti-COVID-19 drug candidates with hepatic transporters may cause liver toxicity and affect pharmacokinetics

Transporters in the human liver play a major role in the clearance of endo- and xenobiotics. Apical (canalicular) transporters extrude compounds to the bile, while basolateral hepatocyte transporters promote the uptake of, or expel, various compounds from/into the venous blood stream. In the present work we have examined the in vitro interactions of some key repurposed drugs advocated to treat COVID-19 (lopinavir, ritonavir, ivermectin, remdesivir and favipiravir), with the key drug transporters of hepatocytes. These transporters included ABCB11/BSEP, ABCC2/MRP2, and SLC47A1/MATE1 in the canalicular membrane, as well as ABCC3/MRP3, ABCC4/MRP4, SLC22A1/OCT1, SLCO1B1/OATP1B1, SLCO1B3/OATP1B3, and SLC10A1/NTCP, residing in the basolateral membrane. Lopinavir and ritonavir in low micromolar concentrations inhibited BSEP and MATE1 exporters, as well as OATP1B1/1B3 uptake transporters. Ritonavir had a similar inhibitory pattern, also inhibiting OCT1. Remdesivir strongly inhibited MRP4, OATP1B1/1B3, MATE1 and OCT1. Favipiravir had no significant effect on any of these transporters. Since both general drug metabolism and drug-induced liver toxicity are strongly dependent on the functioning of these transporters, the various interactions reported here may have important clinical relevance in the drug treatment of this viral disease and the existing co-morbidities.

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 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.

Ivermectin to prevent hospitalizations in patients with COVID-19 (IVERCOR-COVID19) a randomized, double-blind, placebo-controlled trial

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) has changed our lives. The scientific community has been investigating re-purposed treatments to prevent disease progression in coronavirus disease (COVID-19) patients.

OBJECTIVE

To determine whether ivermectin treatment can prevent hospitalization in individuals with early COVID-19.

DESIGN, SETTING AND PARTICIPANTS

A randomized, double-blind, placebo-controlled study was conducted in non-hospitalized individuals with COVID-19 in Corrientes, Argentina. Patients with SARS-CoV-2 positive nasal swabs were contacted within 48 h by telephone to invite them to participate. The trial randomized 501 patients between August 19th 2020 and February 22nd 2021.

INTERVENTION

Patients were randomized to ivermectin (N = 250) or placebo (N = 251) arms in a staggered dose, according to the patient's weight, for 2 days.

MAIN OUTCOMES AND MEASURES

The efficacy of ivermectin to prevent hospitalizations was evaluated as primary outcome. We evaluated secondary outcomes in relationship to safety and other efficacy end points.

RESULTS

The mean age was 42 years (SD ± 15.5) and the median time since symptom onset to the inclusion was 4 days [interquartile range 3-6]. The primary outcome of hospitalization was met in 14/250 (5.6%) individuals in ivermectin group and 21/251 (8.4%) in placebo group (odds ratio 0.65; 95% confidence interval, 0.32-1.31; p = 0.227). Time to hospitalization was not statistically different between groups. The mean time from study enrollment to invasive mechanical ventilatory support (MVS) was 5.25 days (SD ± 1.71) in ivermectin group and 10 days (SD ± 2) in placebo group, (p = 0.019). There were no statistically significant differences in the other secondary outcomes including polymerase chain reaction test negativity and safety outcomes.

LIMITATIONS

Low percentage of hospitalization events, dose of ivermectin and not including only high-risk population.

CONCLUSION

Ivermectin had no significant effect on preventing hospitalization of patients with COVID-19. Patients who received ivermectin required invasive MVS earlier in their treatment. No significant differences were observed in any of the other secondary outcomes.

TRIAL REGISTRATION

ClinicalTrials.gov NCT04529525 .

Current Use of Ivermectin in Dermatology, Tropical Medicine, and COVID-19: An Update on Pharmacology, Uses, Proven and Varied Proposed Mechanistic Action

Ivermectin is a broad-spectrum antiparasitic drug with anti-inflammatory, anti-viral, anti-bacterial, and anti-tumor effects. In this review, we discuss the history, pharmacology, multimodal actions, indications in dermatology and tropical medicine, therapeutic and prophylactic use of ivermectin in COVID-19, safety, adverse effects, special considerations, and drug interactions of ivermectin.

Neurological Effects of Sars-Cov-2 And Neurotoxicity of Antiviral Drugs Against Covid-19

Severe Acute Respiratory Syndrome (SARS) is caused by different SARS viruses. In 2020, novel coronavirus (SARS-CoV-2) led to an ongoing pandemic, known as "Coronavirus Disease 2019 (COVID-19)". The disease can spread among individuals through direct (via saliva, respiratory secretions or secretion droplets) or indirect (through contaminated objects or surfaces) contact. The pandemic has spread rapidly from Asia to Europe and later to America. It continues to affect all parts of the world at an increasing rate. There have been over 92 million confirmed cases of COVID-19 by mid-January 2021. The similarity of homological sequences between SARS-CoV-2 and other SARS-CoVs is high. In addition, clinical symptoms of SARS-CoV-2 and other SARS viruses show similarities. However, some COVID-19 cases show neurologic signs like headache, loss of smell, hiccups and encephalopathy. The drugs used in the palliative treatment of the disease also have some neurotoxic effects. Currently, there are approved vaccines for COVID-19. However, there is a need for specific therapeutics against COVID-19. This review will describe the neurological effects of SARS-CoV-2 and the neurotoxicity of COVID-19 drugs used in clinics. Drugs used in the treatment of COVID-19 will be evaluated by their mechanism of action and their toxicological effects.

Ivermectin for Prevention and Treatment of COVID-19 Infection: A Systematic Review, Meta-analysis, and Trial Sequential Analysis to Inform Clinical Guidelines

BACKGROUND

Repurposed medicines may have a role against the SARS-CoV-2 virus. The antiparasitic ivermectin, with antiviral and anti-inflammatory properties, has now been tested in numerous clinical trials.

AREAS OF UNCERTAINTY

We assessed the efficacy of ivermectin treatment in reducing mortality, in secondary outcomes, and in chemoprophylaxis, among people with, or at high risk of, COVID-19 infection.

DATA SOURCES

We searched bibliographic databases up to April 25, 2021. Two review authors sifted for studies, extracted data, and assessed risk of bias. Meta-analyses were conducted and certainty of the evidence was assessed using the GRADE approach and additionally in trial sequential analyses for mortality. Twenty-four randomized controlled trials involving 3406 participants met review inclusion.

THERAPEUTIC ADVANCES

Meta-analysis of 15 trials found that ivermectin reduced risk of death compared with no ivermectin (average risk ratio 0.38, 95% confidence interval 0.19-0.73; n = 2438; I2 = 49%; moderate-certainty evidence). This result was confirmed in a trial sequential analysis using the same DerSimonian-Laird method that underpinned the unadjusted analysis. This was also robust against a trial sequential analysis using the Biggerstaff-Tweedie method. Low-certainty evidence found that ivermectin prophylaxis reduced COVID-19 infection by an average 86% (95% confidence interval 79%-91%). Secondary outcomes provided less certain evidence. Low-certainty evidence suggested that there may be no benefit with ivermectin for "need for mechanical ventilation," whereas effect estimates for "improvement" and "deterioration" clearly favored ivermectin use. Severe adverse events were rare among treatment trials and evidence of no difference was assessed as low certainty. Evidence on other secondary outcomes was very low certainty.

CONCLUSIONS

Moderate-certainty evidence finds that large reductions in COVID-19 deaths are possible using ivermectin. Using ivermectin early in the clinical course may reduce numbers progressing to severe disease. The apparent safety and low cost suggest that ivermectin is likely to have a significant impact on the SARS-CoV-2 pandemic globally.

Ivermectin for Prevention and Treatment of COVID-19 Infection: A Systematic Review, Meta-analysis, and Trial Sequential Analysis to Inform Clinical Guidelines

BACKGROUND

Repurposed medicines may have a role against the SARS-CoV-2 virus. The antiparasitic ivermectin, with antiviral and anti-inflammatory properties, has now been tested in numerous clinical trials.

AREAS OF UNCERTAINTY

We assessed the efficacy of ivermectin treatment in reducing mortality, in secondary outcomes, and in chemoprophylaxis, among people with, or at high risk of, COVID-19 infection.

DATA SOURCES

We searched bibliographic databases up to April 25, 2021. Two review authors sifted for studies, extracted data, and assessed risk of bias. Meta-analyses were conducted and certainty of the evidence was assessed using the GRADE approach and additionally in trial sequential analyses for mortality. Twenty-four randomized controlled trials involving 3406 participants met review inclusion.

THERAPEUTIC ADVANCES

Meta-analysis of 15 trials found that ivermectin reduced risk of death compared with no ivermectin (average risk ratio 0.38, 95% confidence interval 0.19-0.73; n = 2438; I2 = 49%; moderate-certainty evidence). This result was confirmed in a trial sequential analysis using the same DerSimonian-Laird method that underpinned the unadjusted analysis. This was also robust against a trial sequential analysis using the Biggerstaff-Tweedie method. Low-certainty evidence found that ivermectin prophylaxis reduced COVID-19 infection by an average 86% (95% confidence interval 79%-91%). Secondary outcomes provided less certain evidence. Low-certainty evidence suggested that there may be no benefit with ivermectin for "need for mechanical ventilation," whereas effect estimates for "improvement" and "deterioration" clearly favored ivermectin use. Severe adverse events were rare among treatment trials and evidence of no difference was assessed as low certainty. Evidence on other secondary outcomes was very low certainty.

CONCLUSIONS

Moderate-certainty evidence finds that large reductions in COVID-19 deaths are possible using ivermectin. Using ivermectin early in the clinical course may reduce numbers progressing to severe disease. The apparent safety and low cost suggest that ivermectin is likely to have a significant impact on the SARS-CoV-2 pandemic globally.

Safety and Efficacy of Ivermectin and Doxycycline Monotherapy and in Combination in the Treatment of COVID-19: A Scoping Review

INTRODUCTION AND OBJECTIVE

Ivermectin (IVM) and doxycycline (DOXY) have demonstrated in-vitro activity against SARS-CoV-2, and have a reasonable safety profile. The objective of this systematic review was to explore the evidence in the literature on the safety and efficacy of their use as monotherapy and combination therapy in COVID-19 management.

METHODS

After prospectively registering the study protocol with the Open Science Framework, we searched PubMed, Google Scholar, clinicaltrials.gov, various pre-print servers and reference lists for relevant records published until 16 February, 2021 using appropriate search strategies. Baseline features and data pertaining to efficacy and safety outcomes were extracted separately for IVM monotherapy, DOXY monotherapy, and IVM + DOXY combination therapy. Methodological quality was assessed based on the study design.

RESULTS

Out of 200 articles screened, 19 studies (six retrospective cohort studies, seven randomised controlled trials, five non-randomised trials, one case series) with 8754 unique patients with multiple stages of COVID-19 were included; four were pre-prints and one was an unpublished clinicaltrials.gov document. The comparator was standard care and 'hydroxychloroquine + azithromycin' in seven and three studies respectively, and two studies were placebo controlled; six studies did not have a comparator. IVM monotherapy, DOXY monotherapy and IVM + DOXY were explored in eight, five and five studies, respectively; one study compared IVM monotherapy and IVM + DOXY with placebo. While all studies described efficacy, the safety profile was described in only six studies. Efficacy outcomes were mixed with some studies concluding in favour of the intervention and some studies displaying no significant benefit; barring one study that described 9/183 patients with erosive esophagitis and non-ulcer dyspepsia with IVM + DOXY (without causality assessment details), there were no new safety signals of concern with any of the three interventions considered. The quality of studies varied widely, with five studies having a 'good' methodological quality.

CONCLUSIONS

Evidence is not sufficiently strong to either promote or refute the efficacy of IVM, DOXY, or their combination in COVID-19 management.

SYSTEMATIC REVIEW PROTOCOL REGISTRATION DETAILS

Open Science Framework: https://osf.io/n7r2j .

A Large Impact of Obesity on the Disposition of Ivermectin, Moxidectin and Eprinomectin in a Canine Model: Relevance for COVID-19 Patients

Ivermectin (IVM) and moxidectin (MOX) are used extensively as parasiticides in veterinary medicine. Based on in vitro data, IVM has recently been proposed for the prevention and treatment of COVID-19 infection, a condition for which obesity is a major risk factor. In patients, IVM dosage is based on total body weight and there are no recommendations to adjust dosage in obese patients. The objective of this study was to establish, in a canine model, the influence of obesity on the clearance and steady-state volume of distribution of IVM, MOX, and a third analog, eprinomectin (EPR). An experimental model of obesity in dogs was based on a high calorie diet. IVM, MOX, and EPR were administered intravenously, in combination, to a single group of dogs in two circumstances, during a control period and when body weight had been increased by 50%. In obese dogs, clearance, expressed in absolute values (L/day), was not modified for MOX but was reduced for IVM and EPR, compared to the initial control state. However, when scaled by body weight (L/day/kg), plasma clearance was reduced by 55, 42, and 63%, for IVM, MOX and EPR, respectively. In contrast, the steady-state volume of distribution was markedly increased, in absolute values (L), by obesity. For IVM and MOX, this obese dog model suggests that the maintenance doses in the obese subject should be based on lean body weight rather than total weight. On the other hand, the loading dose, when required, should be based on the total body weight of the obese subject.

Repurposing Ivermectin for COVID-19: Molecular Aspects and Therapeutic Possibilities

As of January 2021, SARS-CoV-2 has killed over 2 million individuals across the world. As such, there is an urgent need for vaccines and therapeutics to reduce the burden of COVID-19. Several vaccines, including mRNA, vector-based vaccines, and inactivated vaccines, have been approved for emergency use in various countries. However, the slow roll-out of vaccines and insufficient global supply remains a challenge to turn the tide of the pandemic. Moreover, vaccines are important tools for preventing the disease but therapeutic tools to treat patients are also needed. As such, since the beginning of the pandemic, repurposed FDA-approved drugs have been sought as potential therapeutic options for COVID-19 due to their known safety profiles and potential anti-viral effects. One of these drugs is ivermectin (IVM), an antiparasitic drug created in the 1970s. IVM later exerted antiviral activity against various viruses including SARS-CoV-2. In this review, we delineate the story of how this antiparasitic drug was eventually identified as a potential treatment option for COVID-19. We review SARS-CoV-2 lifecycle, the role of the nucleocapsid protein, the turning points in past research that provided initial 'hints' for IVM's antiviral activity and its molecular mechanism of action- and finally, we culminate with the current clinical findings.

Use of ivermectin in the treatment of Covid-19: A pilot trial

•

Ivermectin has an antiviral effect on DNA and RNA viral families.

•

This pilot clinical trial demonstrated the antiviral effects and safety of ivermectin in patients with mild COVID-19.

•

The antiviral effect of ivermectin appears to be dose-dependent.

•

Larger clinical trials should be carried out to confirm its clinical efficacy for COVID-19.

Objectives

In this randomized open-label trial pilot study we assessed the antiviral effects and safety of various doses of ivermectin in patients with mild clinical symptoms of COVID-19.

Methods

Patients were randomly assigned to receive standard of care (SOC) treatment at hospital admission; SOC plus ivermectin 100 mcg/kg; SOC plus ivermectin 200 mcg/kg; or SOC plus ivermectin 400 mcg/kg. The primary assessed endpoint was the proportion of patients who achieved two consecutive negative SARS-CoV-2 RT PCR tests within 7 days of the start of the dosing period. This study was registered at ClinicalTrials.gov (NCT04431466).

Results

A total of 32 patients were enrolled and randomized to treatment. SOC treatment together with ivermectin did not result in any serious adverse events. All patients exhibited a reduction in SARS-CoV-2 viral load within 7 days; however, those who received ivermectin had a more consistent decrease as compared to the SOC alone group, characterized by a shorter time for obtaining two consecutive negative SARS-CoV-2 RT PCR tests.

Conclusions

Ivermectin is safe in patients with SARS-CoV-2, reducing symptomatology and the SARS-CoV-2 viral load. This antiviral effect appears to depend on the dose used, and if confirmed in future studies, it suggests that ivermectin may be a useful adjuvant to the SOC treatment in patients with mild COVID-19 symptoms.

From hydroxychloroquine to ivermectin: what are the anti-viral properties of anti-parasitic drugs to combat SARS-CoV-2?

BACKGROUND

Nearly a year into the COVID-19 pandemic, we still lack effective anti-SARS-CoV-2 drugs with substantial impact on mortality rates except for dexamethasone. As the search for effective antiviral agents continues, we aimed to review data on the potential of repurposing antiparasitic drugs against viruses in general, with an emphasis on coronaviruses.

METHODS

We performed a review by screening in vitro and in vivo studies that assessed the antiviral activity of several antiparasitic agents: chloroquine, hydroxychloroquine (HCQ), mefloquine, artemisinins, ivermectin, nitazoxanide (NTZ), niclosamide, atovaquone and albendazole.

RESULTS

For HCQ and chloroquine we found ample in vitro evidence of antiviral activity. Cohort studies that assessed the use of HCQ for COVID-19 reported conflicting results, but randomized controlled trials (RCTs) demonstrated no effect on mortality rates and no substantial clinical benefits of HCQ used either for prevention or treatment of COVID-19. We found two clinical studies of artemisinins and two studies of NTZ for treatment of viruses other than COVID-19, all of which showed mixed results. Ivermectin was evaluated in one RCT and few observational studies, demonstrating conflicting results. As the level of evidence of these data is low, the efficacy of ivermectin against COVID-19 remains to be proven. For chloroquine, HCQ, mefloquine, artemisinins, ivermectin, NTZ and niclosamide, we found in vitro studies showing some effects against a wide array of viruses. We found no relevant studies for atovaquone and albendazole.

CONCLUSIONS

As the search for an effective drug active against SARS-CoV-2 continues, we argue that pre-clinical research of possible antiviral effects of compounds that could have antiviral activity should be conducted. Clinical studies should be conducted when sufficient in vitro evidence exists, and drugs should be introduced into widespread clinical use only after being rigorously tested in RCTs. Such a search may prove beneficial in this pandemic or in outbreaks yet to come.

Therapeutic Strategies in the Management of COVID-19

Since December 2019, SARS-CoV-2 (COVID-19), novel corona virus has caused pandemic globally, with rise in the number of cases and death of the patients. Vast majority of the countries that are dealing with rise in the active cases and death of patients suffering from novel corona viruses COVID-19 are trying to content the virus by isolating the patients and treating them with the approved antiviral that have been previously used in treating SARS, MERS, and drugs that are used to treat other viral infections. Some of these are under clinical trials. At present there are no therapeutically effective antiviral present and there are no vaccines or drugs available that are clinically approved for treating the corona virus. The current strategy is to re-purpose the available drugs or antiviral that can minimise or reduce the burden of the health care emergencies. In this article the reuse of antiviral, US-FDA approved drugs, plant based therapeutic, anti-malarial, anti-parasitic, anti-HIV drugs and the traditional medicines that are being currently used in treating the symptoms of COVID-19 patients is discussed emphasis is also given on the treatment using monoclonal antibodies. The present article provides the therapeutic strategies that will qualify as one of the best available treatment for the better management of the COVID-19 patients in order to achieve medical benefits.