Efficacy and Safety of Sarilumab in patients with COVID19 Pneumonia: A Randomized, Phase III Clinical Trial (SARTRE Study)

Placebo effects on all-cause mortality of patients with COVID-19 in randomized controlled trials of interleukin 6 antagonists: A systematic review and network meta-analysis

AIM

Many randomized controlled trials (RCTs) have investigated the use of interleukin 6 antagonists for the treatment of coronavirus disease 2019 (COVID-19), yielding inconsistent results. This network meta-analysis (NMA) aimed to identify the source of these inconsistent results by reassessing whether participants treated with standard of care (SoC) plus placebo have different all-cause mortality from those treated with SoC alone and to reevaluate the efficacy of interleukin 6 antagonists in the treatment of COVID-19.

METHODS

We conducted a systematic search for relevant RCTs from the inception of electronic databases through 1 September 2022. The primary outcome was all-cause mortality. The secondary outcomes were the incidences of major medical events, secondary infections, all-cause discontinuation, and serious adverse events.

RESULTS

The results of NMA of 33 RCTs showed that patients with COVID-19 treated with SoC plus placebo had lower odds of all-cause mortality than those who received SoC alone (OR, 0.75 [95% confidence interval, 0.58-0.97]). This finding remained consistent after excluding studies with no incident deaths. In addition, when we consider the impact of the widely promoted COVID-19 vaccination and newly developed antiviral treatment strategy, the results from the analysis of the RCT published in 2021 and 2022 remained similar.

CONCLUSION

These findings suggest the potential influence of placebo effects on the treatment outcomes of COVID-19 in RCTs. When evaluating the efficacy of treatment strategies for COVID-19, it is crucial to consider the use of placebo in the design of clinical trials.

Quality of reporting of adverse events in clinical trials of covid-19 drugs: systematic review

Objective

To assess the quality of reporting of adverse events in clinical trials of covid-19 drugs based on the CONSORT (Consolidated Standards of Reporting Trials) harms extension and according to clinical trial design, and to examine reporting of serious adverse events in drug trials published on PubMed versus clinical trial summaries on ClinicalTrials.gov.

Design

Systematic review.

Data sources

PubMed and ClinicalTrials.gov registries were searched from 1 December 2019 to 17 February 2022.

Eligibility criteria for selecting studies

Randomised clinical trials evaluating the efficacy and safety of drugs used to treat covid-19 disease in participants of all ages with suspected, probable, or confirmed SARS-CoV-2 infection were included. Clinical trials were screened on title, abstract, and text by two authors independently. Only articles published in French and English were selected. The Cochrane risk of bias tool for randomised trials (RoB 2) was used to assess risk of bias.

Results

The search strategy identified 1962 randomised clinical trials assessing the efficacy and safety of drugs used to treat covid-19, published in the PubMed database; 1906 articles were excluded after screening and 56 clinical trials were included in the review. Among the 56 clinical trials, no study had a high score for quality of reporting of adverse events, 60.7% had a moderate score, 33.9% had a low score, and 5.4% had a very low score. All clinical trials with a very low score for quality of reporting of adverse events were randomised open label trials. For reporting of serious adverse events, journal articles published on PubMed under-reported 51% of serious adverse events compared with clinical trial summaries published on ClinicalTrials.gov.

Conclusions

In one in three published clinical trials on covid-19 drugs, the quality of reporting of adverse events was low or very low. Differences were found in the number of serious adverse events reported in journal articles versus clinical trial summaries. During the covid-19 pandemic, risk assessment of drugs in clinical trials of covid-19 drugs did not comply with good practice recommendations for publication of results.

Systematic review registration

European Network of Centres for Pharmacoepidemiology and Pharmacovigilance (ENCePP) EUPAS45959.

Interleukin-6 blocking agents for treating COVID-19: a living systematic review

BACKGROUND

It has been reported that people with COVID-19 and pre-existing autoantibodies against type I interferons are likely to develop an inflammatory cytokine storm responsible for severe respiratory symptoms. Since interleukin 6 (IL-6) is one of the cytokines released during this inflammatory process, IL-6 blocking agents have been used for treating people with severe COVID-19.

OBJECTIVES

To update the evidence on the effectiveness and safety of IL-6 blocking agents compared to standard care alone or to a placebo for people with COVID-19.

SEARCH METHODS

We searched the World Health Organization (WHO) International Clinical Trials Registry Platform, the Living OVerview of Evidence (L·OVE) platform, and the Cochrane COVID-19 Study Register to identify studies on 7 June 2022.

SELECTION CRITERIA

We included randomized controlled trials (RCTs) evaluating IL-6 blocking agents compared to standard care alone or to placebo for people with COVID-19, regardless of disease severity.

DATA COLLECTION AND ANALYSIS

Pairs of researchers independently conducted study selection, extracted data and assessed risk of bias. We assessed the certainty of evidence using the GRADE approach for all critical and important outcomes. In this update we amended our protocol to update the methods used for grading evidence by establishing minimal important differences for the critical outcomes.

MAIN RESULTS

This update includes 22 additional trials, for a total of 32 trials including 12,160 randomized participants all hospitalized for COVID-19 disease. We identified a further 17 registered RCTs evaluating IL-6 blocking agents without results available as of 7 June 2022.  The mean age range varied from 56 to 75 years; 66.2% (8051/12,160) of enrolled participants were men. One-third (11/32) of included trials were placebo-controlled. Twenty-two were published in peer-reviewed journals, three were reported as preprints, two trials had results posted only on registries, and results from five trials were retrieved from another meta-analysis. Eight were funded by pharmaceutical companies.  Twenty-six included studies were multicenter trials; four were multinational and 22 took place in single countries. Recruitment of participants occurred between February 2020 and June 2021, with a mean enrollment duration of 21 weeks (range 1 to 54 weeks). Nineteen trials (60%) had a follow-up of 60 days or more. Disease severity ranged from mild to critical disease. The proportion of participants who were intubated at study inclusion also varied from 5% to 95%. Only six trials reported vaccination status; there were no vaccinated participants included in these trials, and 17 trials were conducted before vaccination was rolled out. We assessed a total of six treatments, each compared to placebo or standard care. Twenty trials assessed tocilizumab, nine assessed sarilumab, and two assessed clazakizumab. Only one trial was included for each of the other IL-6 blocking agents (siltuximab, olokizumab, and levilimab). Two trials assessed more than one treatment. Efficacy and safety of tocilizumab and sarilumab compared to standard care or placebo for treating COVID-19 At day (D) 28, tocilizumab and sarilumab probably result in little or no increase in clinical improvement (tocilizumab: risk ratio (RR) 1.05, 95% confidence interval (CI) 1.00 to 1.11; 15 RCTs, 6116 participants; moderate-certainty evidence; sarilumab: RR 0.99, 95% CI 0.94 to 1.05; 7 RCTs, 2425 participants; moderate-certainty evidence). For clinical improvement at ≥ D60, the certainty of evidence is very low for both tocilizumab (RR 1.10, 95% CI 0.81 to 1.48; 1 RCT, 97 participants; very low-certainty evidence) and sarilumab (RR 1.22, 95% CI 0.91 to 1.63; 2 RCTs, 239 participants; very low-certainty evidence). The effect of tocilizumab on the proportion of participants with a WHO Clinical Progression Score (WHO-CPS) of level 7 or above remains uncertain at D28 (RR 0.90, 95% CI 0.72 to 1.12; 13 RCTs, 2117 participants; low-certainty evidence) and that for sarilumab very uncertain (RR 1.10, 95% CI 0.90 to 1.33; 5 RCTs, 886 participants; very low-certainty evidence). Tocilizumab reduces all cause-mortality at D28 compared to standard care/placebo (RR 0.88, 95% CI 0.81 to 0.94; 18 RCTs, 7428 participants; high-certainty evidence). The evidence about the effect of sarilumab on this outcome is very uncertain (RR 1.06, 95% CI 0.86 to 1.30; 9 RCTs, 3305 participants; very low-certainty evidence). The evidence is uncertain for all cause-mortality at ≥ D60 for tocilizumab (RR 0.91, 95% CI 0.80 to 1.04; 9 RCTs, 2775 participants; low-certainty evidence) and very uncertain for sarilumab (RR 0.95, 95% CI 0.84 to 1.07; 6 RCTs, 3379 participants; very low-certainty evidence). Tocilizumab probably results in little to no difference in the risk of adverse events (RR 1.03, 95% CI 0.95 to 1.12; 9 RCTs, 1811 participants; moderate-certainty evidence). The evidence about adverse events for sarilumab is uncertain (RR 1.12, 95% CI 0.97 to 1.28; 4 RCT, 860 participants; low-certainty evidence).  The evidence about serious adverse events is very uncertain for tocilizumab (RR 0.93, 95% CI 0.81 to 1.07; 16 RCTs; 2974 participants; very low-certainty evidence) and uncertain for sarilumab (RR 1.09, 95% CI 0.97 to 1.21; 6 RCTs; 2936 participants; low-certainty evidence). Efficacy and safety of clazakizumab, olokizumab, siltuximab and levilimab compared to standard care or placebo for treating COVID-19 The evidence about the effects of clazakizumab, olokizumab, siltuximab, and levilimab comes from only one or two studies for each blocking agent, and is uncertain or very uncertain.

AUTHORS' CONCLUSIONS

In hospitalized people with COVID-19, results show a beneficial effect of tocilizumab on all-cause mortality in the short term and probably little or no difference in the risk of adverse events compared to standard care alone or placebo. Nevertheless, both tocilizumab and sarilumab probably result in little or no increase in clinical improvement at D28. Evidence for an effect of sarilumab and the other IL-6 blocking agents on critical outcomes is uncertain or very uncertain. Most of the trials included in our review were done before the waves of different variants of concern and before vaccination was rolled out on a large scale. An additional 17 RCTs of IL-6 blocking agents are currently registered with no results yet reported. The number of pending studies and the number of participants planned is low. Consequently, we will not publish further updates of this review.

Sarilumab plus standard of care vs standard of care for the treatment of severe COVID-19: a phase 3, randomized, open-labeled, multi-center study (ESCAPE study)

BACKGROUND

Among interleukin-6 inhibitors suggested for use in COVID-19, there are few robust evidences for the efficacy of sarilumab. Herein, we evaluated the efficacy and safety of sarilumab in severe COVID-19.

METHODS

In this phase 3, open-labeled, randomized clinical trial, conducted at 5 Italian hospitals, adults with severe COVID-19 pneumonia (excluding mechanically ventilated) were randomized 2:1 to receive intravenous sarilumab (400 mg, repeatable after 12 h) plus standard of care (SOC) (arm A) or to continue SOC (arm B). Randomization was web-based. As post-hoc analyses, the participants were stratified according to baseline inflammatory parameters. The primary endpoint was analysed on the modified Intention-To-Treat population, including all the randomized patients who received any study treatment (sarilumab or SOC). It was time to clinical improvement of 2 points on a 7-points ordinal scale, from baseline to day 30. We used Kaplan Meier method and log-rank test to compare the primary outcome between two arms, and Cox regression stratified by clinical center and adjusted for severity of illness, to estimate the hazard ratio (HR). The trial was registered with EudraCT (2020-001390-76).

FINDINGS

Between May 2020 and May 2021, 191 patients were assessed for eligibility, of whom, excluding nine dropouts, 176 were assigned to arm A (121) and B (55). At day 30, no significant differences in the primary endpoint were found (88% [95% CI 81-94] in arm A vs 85% [74-93], HR 1.07 [0.8-1.5] in arm B; log-rank p = 0.50). After stratifying for inflammatory parameters, arm A showed higher probability of improvement than B without statistical significance in the strata with C reactive protein (CRP) < 7 mg/dL (88% [77-96] vs 79% [63-91], HR 1.55 [0.9-2.6]; log-rank p = 0.049) and in the strata with lymphocytes <870/mmc (90% [79-96]) vs (73% [55-89], HR 1.53 [0.9-2.7]; log-rank p = 0.058). Overall, 39/121 (32%) AEs were reported in arm A and 14/55 (23%) in B (p = 0.195), while serious AEs were 22/121 (18%) and 7/55 (11%), respectively (p = 0.244). There were no treatment-related deaths.

INTERPRETATION

The efficacy of sarilumab in severe COVID-19 was not demonstrated both in the overall and in the stratified for severity analysis population. Exploratory analyses suggested that subsets of patients with lower CRP values or lower lymphocyte counts might have had benefit with sarilumab treatment, but this finding would require replication in other studies. The relatively low rate of concomitant corticosteroid use, could partially explain our results.

FUNDING

This study was supported by INMI "Lazzaro Spallanzani" Ricerca Corrente Linea 1 on emerging and reemerging infections, funded by Italian Ministry of Health.

[Should we interfere with the interleukin-6 receptor during COVID-19: What do we know?]

COVID-19 is a viral infection with predominant respiratory tropism. In its most severe forms, the initial viral aggression leads to acute respiratory failure due to damage secondary to an exacerbated inflammatory response provoked by the activation of innate, followed by adaptive immunity. The inflammatory response may entail respiratory distress syndrome, if not multivisceral failure and death. IL-6 receptor inhibitors (Tocilizumab and Sarilumab) have been proposed as treatments. Numerous studies have provided new information, which remains heterogeneous and difficult to interpret. This review is aimed at clarifying the potential role of IL-6 receptor inhibitors in severe forms of COVID-19.

Should We Interfere with the Interleukin-6 Receptor During COVID-19: What Do We Know So Far?

Severe manifestations of COVID-19 consist of acute respiratory distress syndrome due to an initially local reaction leading to a systemic inflammatory response that results in hypoxia. Many therapeutic approaches have been attempted to reduce the clinical consequences of an excessive immune response to viral infection. To date, systemic corticosteroid therapy is still the most effective intervention. More recently, new hope has emerged with the use of interleukin (IL)-6 receptor inhibitors (tocilizumab and sarilumab). However, the great heterogeneity of the methodology and results of published studies obfuscate the true value of this treatment, leading to a confusing synthesis in recent meta-analyses, and the persistence of doubts in terms of patient groups and the appropriate time to treat. Moreover, their effects on the anti-infectious or pro-healing response are still poorly studied. This review aims to clarify the potential role of IL-6 receptor inhibitors in the treatment of severe forms of COVID-19.

Effect of tocilizumab, sarilumab, and baricitinib on mortality among patients hospitalized for COVID-19 treated with corticosteroids: a systematic review and meta-analysis

BACKGROUND

Randomized controlled trials (RCT) established the mortality reduction by tocilizumab (Actemra), baricitinib (Olumiant), and sarilumab (Kevzara) in hospitalized COVID-19 patients. However, uncertainty remains about which treatment performs best in patients receiving corticosteroids.

OBJECTIVES

To estimate probabilities of noninferiority between baricitinib and sarilumab compared to tocilizumab in patients treated with corticosteroids.

DATA SOURCES

PubMed, Embase, Cochrane Library, and MedRxiv.

STUDY ELIGIBILITY CRITERIA

Eligible RCTs assigning hospitalized adults with COVID-19 treated with corticosteroids to tocilizumab or baricitinib or sarilumab versus standard of care or placebo (control).

METHODS

Reviewers independently abstracted published data and assessed study quality with the Risk of Bias 2 tool. Unpublished data, if required, were requested from authors of included studies. The outcome of interest was all-cause mortality at 28 days.

PARTICIPANTS

Twenty-seven RCTs with 13 549 patients were included. Overall, the risk of bias was low. Bayesian pairwise meta-analyses were used to aggregate results of each treatment versus control. The average odds ratio for mortality was 0.78 (95% credible interval [CrI]: 0.65, 0.94) for tocilizumab; 0.78 (95% CrI: 0.56, 1.03) for baricitinib; and 0.91 (95% CrI: 0.60, 1.40) for sarilumab. The certainty of evidence (GRADE) ranged from moderate to low. Bayesian meta-regressions with multiple priors were used to estimate probabilities of noninferiority (margin of 13% greater effect by tocilizumab). Compared to tocilizumab, there were ≤94% and 90% probabilities of noninferiority with baricitinib and sarilumab, respectively.

RESULTS

All but two studies included data with only indirect evidence for the comparison of interest.

CONCLUSIONS

Among hospitalized COVID-19 treated with corticosteroids, there are high probabilities that both baricitinib and sarilumab are associated with similar mortality reductions in comparison to tocilizumab.

Immune-Based Therapy for Hospitalized Patients With COVID-19 and Risk of Secondary Infections: A Systematic Review and Meta-analysis

Background

Immune-based therapies are standard-of-care treatment for coronavirus disease 2019 (COVID-19) patients requiring hospitalization. However, safety concerns related to the potential risk of secondary infections may limit their use.

Methods

We searched OVID Medline, Ovid EMBASE, SCOPUS, Cochrane Library, clinicaltrials.gov, and PROSPERO in October 2020 and updated the search in November 2021. We included randomized controlled trials (RCTs). Pairs of reviewers screened abstracts and full studies and extracted data in an independent manner. We used RevMan to conduct a meta-analysis using random-effects models to calculate the pooled risk ratio (RR) and 95% CI for the incidence of infection. Statistical heterogeneity was determined using the I ² statistic. We assessed risk of bias for all studies and rated the certainty of evidence using the Grading of Recommendations Assessment, Development, and Evaluation methodology. We conducted a meta-regression using the R package to meta-explore whether age, sex, and invasive mechanical ventilation modified risk of infection with immune-based therapies. The protocol is registered with PROSPERO (CRD42021229406).

Results

This was a meta-analysis of 37 RCTs including 32 621 participants (mean age, 60 years; 64% male). The use of immune-based therapy for COVID-19 conferred mild protection for the occurrence of secondary infections (711/15 721, 4.5%, vs 616/16 900, 3.6%; RR, 0.82; 95% CI, 0.71-0.95; P = .008; I ² = 28%). A subgroup analysis did not identify any subgroup effect by type of immune-based therapies (P = .85). A meta-regression revealed no impact of age, sex, or mechanical ventilation on the effect of immune-based therapies on risk of infection.

Conclusions

We identified moderate-certainty evidence that the use of immune-based therapies in COVID-19 requiring hospitalization does not increase the risk of secondary infections.

The evidence from clinical trials on colchicine and corticosteroids' effect on COVID-19: a systematic review and meta-analysis

OBJECTIVES

With no clear end for the outbreak, identifying the drugs that are effective in COVID-19's management is of utmost importance to reduce the impact on the general population and the healthcare systems.

METHODS

This is a systematic review and a meta-analysis evaluating the evidence from clinical trials on the effect of colchicine and corticosteroids against COVID-19. In this review, we have systematically searched five databases [(PubMed, Embase, clinicaltrials.gov, ICTRP, CINAHL (EBSCO)]. Cochrane's data extraction sheet was used to collect the required information, and RevMan-5.4.1 was used to conduct the meta-analysis and to assess the risk of bias. The review was registered in Prospero (CRD42022299718).

RESULTS

The total number of included studies was 17, with 18,956 participants; the majority were male 12,001. Out of which, 8772 participants were on colchicine, 569 took methylprednisolone, and 64 patients received prednisolone. The meta-analysis has shown that colchicine had no significant effect on reducing the mortality rate among COVID-19 patients [OR 0.98(95% CI 0.90-1.08), p = .70), I²:1%)], corticosteroids have significantly reduced the mortality rates [OR 0.55 (95% CI 0.33-0.91), p = .02, I²:40]. Colchicine did not reduce the incidence of ICU admissions [OR 0.74 (95% CI 0.39-1.40), p = .35, I²:0%], while steroidal drugs significantly reduced the ICU admissions [OR 0.42 (95% CI 0.23-0.78), p = .005, I²:0%]. Unlike steroidal drugs [OR 0.53 (95% CI 0.30-0.95), p = .03, I²:61%], colchicine failed to reduce the need for mechanical ventilation [OR 0.73 (95% CI 0.48-1.10), p = .13, I²:76%]. Steroidal drugs significantly reduced the duration of hospitalization among COVID-19 patients [OR -0.50 (95% CI -0.79-0.21), p = .0007, I²:36%].

CONCLUSIONS

The use of colchicine did not significantly reduce the mortality rate, ICU admissions, and mechanical ventilation among COVID-19 patients. Conversely, corticosteroids significantly reduced the mortality rate, ICU admissions, mechanical ventilation, and hospitalization duration among COVID-19 patients.

Clinical efficacy and safety of interleukin-6 receptor antagonists (tocilizumab and sarilumab) in patients with COVID-19: a systematic review and meta-analysis

This study investigated the efficacy and safety of interleukin-6 (IL-6) receptor antagonists with standard care treatment in patients with coronavirus disease 2019 (COVID-19). The randomized controlled trials were identified through systematic searches of electronic databases through February 10, 2022. In total, 17 trials comprising 8,614 patients were included. Compared with exclusive standard care or placebo, IL-6 receptor antagonists with standard of care treatment were associated with a significantly reduced all-cause mortality at 28 days (pooled risk ratios [RR], 0.88; 95% confidence interval (CI), 0.82-0.95; 17 studies) and progression to invasive mechanical ventilation (RR, 0.79; 95% CI, 0.71-0.88; nine studies). Particularly, the subgroup of patients with moderate-to-severe COVID-19 showed a significant mortality benefit (RR, 0.89; 95% CI, 0.81-0.96; four studies) and a reduced risk for mechanical ventilation (RR, 0.80; 95% CI, 0.70-0.91; three studies) with tocilizumab treatment. The frequency of serious adverse events was lower in the tocilizumab treatment group than in the standard of care treatment group (RR, 0.83; 95% CI, 0.71-0.97; 11 studies), with no significant difference in the sarilumab treatment group (RR, 1.12; 95% CI, 0.89-1.40; four studies). Our meta-analysis demonstrated that tocilizumab treatment showed promising results in reducing 28-day mortality and progression to mechanical ventilation in patients with moderate-to-severe COVID-19, without the burden of serious adverse events.Trial registration: Clinical Trials Registry India identifier: CTRI/2020/05/025369.The proper registration is PROSPERO: registration number CRD42021294120.

Innate immunity, cytokine storm, and inflammatory cell death in COVID-19

The innate immune system serves as the first line of defense against invading pathogens; however, dysregulated innate immune responses can induce aberrant inflammation that is detrimental to the host. Therefore, careful innate immune regulation is critical during infections. The coronavirus disease 2019 (COVID-19) pandemic is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and has resulted in global morbidity and mortality as well as socio-economic stresses. Innate immune sensing of SARS-CoV-2 by multiple host cell pattern recognition receptors leads to the production of various pro-inflammatory cytokines and the induction of inflammatory cell death. These processes can contribute to cytokine storm, tissue damage, and acute respiratory distress syndrome. Here, we discuss the sensing of SARS-CoV-2 to induce innate immune activation and the contribution of this innate immune signaling in the development and severity of COVID-19. In addition, we provide a conceptual framework for innate immunity driving cytokine storm and organ damage in patients with severe COVID-19. A better understanding of the molecular mechanisms regulated by innate immunity is needed for the development of targeted modalities that can improve patient outcomes by mitigating severe disease.

IL-6 signalling biomarkers in hospitalised patients with moderate to severe SARS-CoV-2 infection in a single centre study in Sweden

Background

Method

Results

Conclusion

Care for adults with COVID ‐19: living guidelines from the National COVID ‐19 Clinical Evidence Taskforce

Introduction

The Australian National COVID‐19 Clinical Evidence Taskforce was established in March 2020 to maintain up‐to‐date recommendations for the treatment of people with coronavirus disease 2019 (COVID‐19). The original guideline (April 2020) has been continuously updated and expanded from nine to 176 recommendations, facilitated by the rapid identification, appraisal, and analysis of clinical trial findings and subsequent review by expert panels.

Main recommendations

In this article, we describe the recommendations for treating non‐pregnant adults with COVID‐19, as current on 1 August 2022 (version 61.0). The Taskforce has made specific recommendations for adults with severe/critical or mild disease, including definitions of disease severity, recommendations for therapy, COVID‐19 prophylaxis, respiratory support, and supportive care.

Changes in management as a result of the guideline

The Taskforce currently recommends eight drug treatments for people with COVID‐19 who do not require supplemental oxygen (inhaled corticosteroids, casirivimab/imdevimab, molnupiravir, nirmatrelvir/ritonavir, regdanvimab, remdesivir, sotrovimab, tixagevimab/cilgavimab) and six for those who require supplemental oxygen (systemic corticosteroids, remdesivir, tocilizumab, sarilumab, baricitinib, casirivimab/imdevimab). Based on evidence of their achieving no or only limited benefit, ten drug treatments or treatment combinations are not recommended; an additional 42 drug treatments should only be used in the context of randomised trials. Additional recommendations include support for the use of continuous positive airway pressure, prone positioning, and endotracheal intubation in patients whose condition is deteriorating, and prophylactic anticoagulation for preventing venous thromboembolism. The latest updates and full recommendations are available at www.covid19evidence.net.au.

Pharmaco-immunomodulatory interventions for averting cytokine storm-linked disease severity in SARS-CoV-2 infection

The year 2020 is characterised by the COVID-19 pandemic that has quelled more than half a million lives in recent months. We are still coping with the negative repercussions of COVID-19 pandemic in 2021, in which the 2nd wave in India resulted in a high fatality rate. Regardless of emergency vaccine approvals and subsequent meteoric global vaccination drives in some countries, hospitalisations for COVID-19 will continue to occur due to the propensity of mutation in SARS-CoV-2 virus. The immune response plays a vital role in the control and resolution of infectious diseases. However, an impaired immune response is responsible for the severity of the respiratory distress in many diseases. The severe COVID-19 infection persuaded cytokine storm that has been linked with acute respiratory distress syndrome (ARDS), culminates into vital organ failures and eventual death. Thus, safe and effective therapeutics to treat hospitalised patients remains a significant unmet clinical need. In that state, any clue of possible treatments, which save patients life, can be treasured for this time point. Many cohorts and clinical trial studies demonstrated that timely administration of immunomodulatory drugs on severe COVID-19 patients may mitigate the disease severity, hospital stay and mortality. This article addresses the severity and risk factors of hypercytokinemia in COVID-19 patients, with special emphasis on prospective immunomodulatory therapies.

Innate immunity: the first line of defense against SARS-CoV-2

The coronavirus disease 2019 (COVID-19) pandemic, caused by severe acute respiratory syndrome coronavirus (SARS-CoV)-2, continues to cause substantial morbidity and mortality. While most infections are mild, some patients experience severe and potentially fatal systemic inflammation, tissue damage, cytokine storm and acute respiratory distress syndrome. The innate immune system acts as the first line of defense, sensing the virus through pattern recognition receptors and activating inflammatory pathways that promote viral clearance. Here, we discuss innate immune processes involved in SARS-CoV-2 recognition and the resultant inflammation. Improved understanding of how the innate immune system detects and responds to SARS-CoV-2 will help identify targeted therapeutic modalities that mitigate severe disease and improve patient outcomes.