Applying lessons learned from COVID-19 therapeutic trials to improve future ALI/ARDS trials

Viral and Host Factors Are Associated With Mortality in Hospitalized Patients With COVID-19

BACKGROUND

Persistent mortality in adults hospitalized due to acute COVID-19 justifies pursuit of disease mechanisms and potential therapies. The aim was to evaluate which virus and host response factors were associated with mortality risk among participants in Therapeutics for Inpatients with COVID-19 (TICO/ACTIV-3) trials.

METHODS

A secondary analysis of 2625 adults hospitalized for acute SARS-CoV-2 infection randomized to 1 of 5 antiviral products or matched placebo in 114 centers on 4 continents. Uniform, site-level collection of participant baseline clinical variables was performed. Research laboratories assayed baseline upper respiratory swabs for SARS-CoV-2 viral RNA and plasma for anti-SARS-CoV-2 antibodies, SARS-CoV-2 nucleocapsid antigen (viral Ag), and interleukin-6 (IL-6). Associations between factors and time to mortality by 90 days were assessed using univariate and multivariable Cox proportional hazards models.

RESULTS

Viral Ag ≥4500 ng/L (vs <200 ng/L; adjusted hazard ratio [aHR], 2.07; 1.29-3.34), viral RNA (<35 000 copies/mL [aHR, 2.42; 1.09-5.34], ≥35 000 copies/mL [aHR, 2.84; 1.29-6.28], vs below detection), respiratory support (<4 L O2 [aHR, 1.84; 1.06-3.22]; ≥4 L O2 [aHR, 4.41; 2.63-7.39], or noninvasive ventilation/high-flow nasal cannula [aHR, 11.30; 6.46-19.75] vs no oxygen), renal impairment (aHR, 1.77; 1.29-2.42), and IL-6 >5.8 ng/L (aHR, 2.54 [1.74-3.70] vs ≤5.8 ng/L) were significantly associated with mortality risk in final adjusted analyses. Viral Ag, viral RNA, and IL-6 were not measured in real-time.

CONCLUSIONS

Baseline virus-specific, clinical, and biological variables are strongly associated with mortality risk within 90 days, revealing potential pathogen and host-response therapeutic targets for acute COVID-19 disease.

Profiling the dysregulated immune response in sepsis: overcoming challenges to achieve the goal of precision medicine

Sepsis is characterised by a dysregulated host immune response to infection. Despite recognition of its significance, immune status monitoring is not implemented in clinical practice due in part to the current absence of direct therapeutic implications. Technological advances in immunological profiling could enhance our understanding of immune dysregulation and facilitate integration into clinical practice. In this Review, we provide an overview of the current state of immune profiling in sepsis, including its use, current challenges, and opportunities for progress. We highlight the important role of immunological biomarkers in facilitating predictive enrichment in current and future treatment scenarios. We propose that multiple immune and non-immune-related parameters, including clinical and microbiological data, be integrated into diagnostic and predictive combitypes, with the aid of machine learning and artificial intelligence techniques. These combitypes could form the basis of workable algorithms to guide clinical decisions that make precision medicine in sepsis a reality and improve patient outcomes.

Echinacea Polyphenols Inhibit NLRP3-Dependent Pyroptosis, Apoptosis, and Necroptosis via Suppressing NO Production during Lipopolysaccharide-Induced Acute Lung Injury

PANoptosis is an intricate programmed death pathway that involves the interaction between pyroptosis, apoptosis, and necroptosis. We systematically explored the protective effect of Echinacea polyphenols (EPP) against the lipopolysaccharide (LPS)-induced acute lung injury (ALI) and the underlying mechanisms both in vitro and in vivo. We noted that EPP pretreatment could significantly alleviate LPS-induced lung tissue injury and pulmonary edema. EPP inhibited the PANoptosis by regulating the expression of nucleotide-binding oligomerization domain-like receptor protein 3 inflammasome, gasdermin D, caspase-8, caspase-3, and mixed lineage kinase domain-like protein. Meanwhile, a comparative study of EPP and inducible nitric oxide synthase inhibitor S-methylisothiourea sulfate indicated that EPP may play a preprotective role in inhibiting PANoptosis via reducing the activity of inducible nitric oxide synthase and the production of nitric oxide (NO) during ALI. Our results clearly indicated that PANoptosis existed in LPS-induced ALI, and EPP pretreatment could provide obvious protective effects to LPS-induced ALI by inhibiting PANoptosis, which may be related to NO production.

Treating COVID-19: Targeting the Host Response, Not the Virus

In low- and middle-income countries (LMICs), inexpensive generic drugs like statins, ACE inhibitors, and ARBs, especially if used in combination, might be the only practical way to save the lives of patients with severe COVID-19. These drugs will already be available in all countries on the first pandemic day. Because they target the host response to infection instead of the virus, they could be used to save lives during any pandemic. Observational studies show that inpatient statin treatment reduces 28–30-day mortality but randomized controlled trials have failed to show this benefit. Combination treatment has been tested for antivirals and dexamethasone but, with the exception of one observational study in Belgium, not for inexpensive generic drugs. Future pandemic research must include testing combination generic drug treatments that could be used in LMICs.

Infliximab as a potential treatment for COVID-19

INTRODUCTION

As the third year of the SARS-CoV-2 pandemic approaches, COVID-19 continues to cause substantial morbidity and mortality due to waning vaccine efficacy and the emergence of new, highly contagious subvariants and better therapies are urgently needed.

AREAS COVERED

Hospitalized patients who develop hypoxia due to SARS-CoV-2 infection are typically treated with an antiviral agent, remdesivir, as well as an immunomodulator, dexamethasone, but mortality rates for severe COVID-19 remain unacceptably high. Mounting evidence suggests a second immunomodulator added to the standard of care may benefit some hospitalized patients; however, the optimal treatment remains controversial.

EXPERT OPINION

On 2 June 2022, the United States National Institutes of Health reported results from a large, randomized placebo-controlled clinical trial known as ACTIV-1. The study found a mortality benefit and substantially improved clinical status for adults hospitalized with COVID-19 who were treated with infliximab, a chimeric monoclonal antibody that binds to and inhibits TNF-α, and is widely used to treat a variety of autoimmune conditions, including rheumatoid arthritis, Crohn's disease, and ulcerative colitis. This manuscript reviews what is known about infliximab as an immunomodulator for patients with COVID-19 and explores how this agent may be used in the future to address the SARS-CoV-2 pandemic.