Efficacy and safety of metabolic interventions for the treatment of severe COVID-19: in vitro, observational, and non-randomized open-label interventional study.

Background: Viral infection is associated with a significant rewire of the host metabolic pathways, presenting attractive metabolic targets for intervention. Methods: We chart the metabolic response of lung epithelial cells to SARS-CoV-2 infection in primary cultures and COVID-19 patient samples and perform in vitro metabolism-focused drug screen on primary lung epithelial cells infected with different strains of the virus. We perform observational analysis of Israeli patients hospitalized due to COVID-19 and comparative epidemiological analysis from cohorts in Italy and the Veteran's Health Administration in the United States. In addition, we perform a prospective non-randomized interventional open-label study in which 15 patients hospitalized with severe COVID-19 were given 145 mg/day of nanocrystallized fenofibrate added to the standard of care. Results: SARS-CoV-2 infection produced transcriptional changes associated with increased glycolysis and lipid accumulation. Metabolism-focused drug screen showed that fenofibrate reversed lipid accumulation and blocked SARS-CoV-2 replication through a PPARα-dependent mechanism in both alpha and delta variants. Analysis of 3233 Israeli patients hospitalized due to COVID-19 supported in vitro findings. Patients taking fibrates showed significantly lower markers of immunoinflammation and faster recovery. Additional corroboration was received by comparative epidemiological analysis from cohorts in Europe and the United States. A subsequent prospective non-randomized interventional open-label study was carried out on 15 patients hospitalized with severe COVID-19. The patients were treated with 145 mg/day of nanocrystallized fenofibrate in addition to standard-of-care. Patients receiving fenofibrate demonstrated a rapid reduction in inflammation and a significantly faster recovery compared to patients admitted during the same period. Conclusions: Taken together, our data suggest that pharmacological modulation of PPARα should be strongly considered as a potential therapeutic approach for SARS-CoV-2 infection and emphasizes the need to complete the study of fenofibrate in large randomized controlled clinical trials. Funding: Funding was provided by European Research Council Consolidator Grants OCLD (project no. 681870) and generous gifts from the Nikoh Foundation and the Sam and Rina Frankel Foundation (YN). The interventional study was supported by Abbott (project FENOC0003). Clinical trial number: NCT04661930.

Clinical and Proteomic Correlates of Plasma ACE2 (Angiotensin-Converting Enzyme 2) in Human Heart Failure.

ACE2 (angiotensin-converting enzyme 2) is a key component of the renin-angiotensin-aldosterone system. Yet, little is known about the clinical and biologic correlates of circulating ACE2 levels in humans. We assessed the clinical and proteomic correlates of plasma (soluble) ACE2 protein levels in human heart failure. We measured plasma ACE2 using a modified aptamer assay among PHFS (Penn Heart Failure Study) participants (n=2248). We performed an association study of ACE2 against ≈5000 other plasma proteins measured with the SomaScan platform. Plasma ACE2 was not associated with ACE inhibitor and angiotensin-receptor blocker use. Plasma ACE2 was associated with older age, male sex, diabetes mellitus, a lower estimated glomerular filtration rate, worse New York Heart Association class, a history of coronary artery bypass surgery, and higher pro-BNP (pro-B-type natriuretic peptide) levels. Plasma ACE2 exhibited associations with 1011 other plasma proteins. In pathway overrepresentation analyses, top canonical pathways associated with plasma ACE2 included clathrin-mediated endocytosis signaling, actin cytoskeleton signaling, mechanisms of viral exit from host cells, EIF2 (eukaryotic initiation factor 2) signaling, and the protein ubiquitination pathway. In conclusion, in humans with heart failure, plasma ACE2 is associated with various clinical factors known to be associated with severe coronavirus disease 2019 (COVID-19), including older age, male sex, and diabetes mellitus, but is not associated with ACE inhibitor and angiotensin-receptor blocker use. Plasma ACE2 protein levels are prominently associated with multiple cellular pathways involved in cellular endocytosis, exocytosis, and intracellular protein trafficking. Whether these have a causal relationship with ACE2 or are relevant to novel coronavirus-2 infection remains to be assessed in future studies.

A randomized clinical trial of lipid metabolism modulation with fenofibrate for acute coronavirus disease 2019.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) cytotoxicity may involve inhibition of peroxisome proliferator-activated receptor alpha. Fenofibrate activates peroxisome proliferator-activated receptor alpha and inhibits SARS-CoV-2 replication in vitro. Whether fenofibrate can be used to treat coronavirus disease 2019 (COVID-19) infection in humans remains unknown. Here, we randomly assigned inpatients and outpatients with COVID-19 within 14 d of symptom onset to 145 mg of oral fenofibrate nanocrystal formulation versus placebo for 10 d, in a double-blinded fashion. The primary endpoint was a severity score whereby participants were ranked across hierarchical tiers incorporating time to death, mechanical ventilation duration, oxygenation, hospitalization and symptom severity and duration. In total, 701 participants were randomized to fenofibrate (n = 351) or placebo (n = 350). The mean age of participants was 49 ± 16 years, 330 (47%) were female, mean body mass index was 28 ± 6 kg/m2 and 102 (15%) had diabetes. Death occurred in 41 participants. Compared with placebo, fenofibrate had no effect on the primary endpoint. The median (interquartile range) rank in the placebo arm was 347 (172, 453) versus 345 (175, 453) in the fenofibrate arm (P = 0.819). There was no difference in secondary and exploratory endpoints, including all-cause death, across arms. There were 61 (17%) adverse events in the placebo arm compared with 46 (13%) in the fenofibrate arm, with slightly higher incidence of gastrointestinal side effects in the fenofibrate group. Overall, among patients with COVID-19, fenofibrate has no significant effect on various clinically relevant outcomes ( NCT04517396 ).

Renin-Angiotensin System Inhibitors in Patients With COVID-19: A Meta-Analysis of Randomized Controlled Trials Led by the International Society of Hypertension.

Background Published randomized controlled trials are underpowered for binary clinical end points to assess the safety and efficacy of renin-angiotensin system inhibitors (RASi) in adults with COVID-19. We therefore performed a meta-analysis to assess the safety and efficacy of RASi in adults with COVID-19. Methods and Results MEDLINE, EMBASE, ClinicalTrials.gov, and the Cochrane Controlled Trial Register were searched for randomized controlled trials that randomly assigned patients with COVID-19 to RASi continuation/commencement versus no RASi therapy. The primary outcome was all-cause mortality at ≤30 days. A total of 14 randomized controlled trials met the inclusion criteria and enrolled 1838 participants (aged 59 years, 58% men, mean follow-up 26 days). Of the trials, 11 contributed data. We found no effect of RASi versus control on all-cause mortality (7.2% versus 7.5%; relative risk [RR], 0.95; [95% CI, 0.69-1.30]) either overall or in subgroups defined by COVID-19 severity or trial type. Network meta-analysis identified no difference between angiotensin-converting enzyme inhibitors versus angiotensin II receptor blockers. RASi users had a nonsignificant reduction in acute myocardial infarction (2.1% versus 3.6%; RR, 0.59; [95% CI, 0.33-1.06]), but increased risk of acute kidney injury (7.0% versus 3.6%; RR, 1.82; [95% CI, 1.05-3.16]), in trials that initiated and continued RASi. There was no increase in need for dialysis or differences in congestive cardiac failure, cerebrovascular events, venous thromboembolism, hospitalization, intensive care admission, inotropes, or mechanical ventilation. Conclusions This meta-analysis of randomized controlled trials evaluating angiotensin-converting enzyme inhibitors/angiotensin II receptor blockers versus control in patients with COVID-19 found no difference in all-cause mortality, a borderline decrease in myocardial infarction, and an increased risk of acute kidney injury with RASi. Our findings provide strong evidence that RASi can be used safely in patients with COVID-19.

Evaluating sources of bias in observational studies of angiotensin-converting enzyme inhibitor/angiotensin II receptor blocker use during COVID-19: beyond confounding.

Concerns over ACE inhibitor or ARB use to treat hypertension during COVID-19 remain unresolved. Although studies using more robust methodologies provided some clarity, sources of bias persist and it remains critical to quickly address this question. In this review, we discuss pernicious sources of bias using a causal model framework, including time-varying confounder, collider, information, and time-dependent bias, in the context of recently published studies. We discuss causal inference methodologies that can address these issues, including causal diagrams, time-to-event analyses, sensitivity analyses, and marginal structural modeling. We discuss effect modification and we propose a role for causal mediation analysis to estimate indirect effects via mediating factors, especially components of the renin--angiotensin system. Thorough knowledge of these sources of bias and the appropriate methodologies to address them is crucial when evaluating observational studies to inform patient management decisions regarding whether ACE inhibitors or ARBs are associated with greater risk from COVID-19.

Inequities in Hypertension Control in the United States Exposed and Exacerbated by COVID-19 and the Role of Home Blood Pressure and Virtual Health Care During and After the COVID-19 Pandemic.

The COVID-19 pandemic is a public health crisis, having killed more than 514 000 US adults as of March 2, 2021. COVID-19 mitigation strategies have unintended consequences on managing chronic conditions such as hypertension, a leading cause of cardiovascular disease and health disparities in the United States. During the first wave of the pandemic in the United States, the combination of observed racial/ethnic inequities in COVID-19 deaths and social unrest reinvigorated a national conversation about systemic racism in health care and society. The 4th Annual University of Utah Translational Hypertension Symposium gathered frontline clinicians, researchers, and leaders from diverse backgrounds to discuss the intersection of these 2 critical social and public health phenomena and to highlight preexisting disparities in hypertension treatment and control exacerbated by COVID-19. The discussion underscored environmental and socioeconomic factors that are deeply embedded in US health care and research that impact inequities in hypertension. Structural racism plays a central role at both the health system and individual levels. At the same time, virtual healthcare platforms are being accelerated into widespread use by COVID-19, which may widen the divide in healthcare access across levels of wealth, geography, and education. Blood pressure control rates are declining, especially among communities of color and those without health insurance or access to health care. Hypertension awareness, therapeutic lifestyle changes, and evidence-based pharmacotherapy are essential. There is a need to improve the implementation of community-based interventions and blood pressure self-monitoring, which can help build patient trust and increase healthcare engagement.

Angiotensin II receptor blocker or angiotensin-converting enzyme inhibitor use and COVID-19-related outcomes among US Veterans.

BACKGROUND: Angiotensin II receptor blockers (ARBs) and angiotensin-converting enzyme inhibitors (ACEIs) may positively or negatively impact outcomes in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We investigated the association of ARB or ACEI use with coronavirus disease 2019 (COVID-19)-related outcomes in US Veterans with treated hypertension using an active comparator design, appropriate covariate adjustment, and negative control analyses. METHODS AND FINDINGS: In this retrospective cohort study of Veterans with treated hypertension in the Veterans Health Administration (01/19/2020-08/28/2020), we compared users of (A) ARB/ACEI vs. non-ARB/ACEI (excluding Veterans with compelling indications to reduce confounding by indication) and (B) ARB vs. ACEI among (1) SARS-CoV-2+ outpatients and (2) COVID-19 hospitalized inpatients. The primary outcome was all-cause hospitalization or mortality (outpatients) and all-cause mortality (inpatients). We estimated hazard ratios (HR) using propensity score-weighted Cox regression. Baseline characteristics were well-balanced between exposure groups after weighting. Among outpatients, there were 5.0 and 6.0 primary outcomes per 100 person-months for ARB/ACEI (n = 2,482) vs. non-ARB/ACEI (n = 2,487) users (HR 0.85, 95% confidence interval [CI] 0.73-0.99, median follow-up 87 days). Among outpatients who were ARB (n = 4,877) vs. ACEI (n = 8,704) users, there were 13.2 and 14.8 primary outcomes per 100 person-months (HR 0.91, 95%CI 0.86-0.97, median follow-up 85 days). Among inpatients who were ARB/ACEI (n = 210) vs. non-ARB/ACEI (n = 275) users, there were 3.4 and 2.0 all-cause deaths per 100 person months (HR 1.25, 95%CI 0.30-5.13, median follow-up 30 days). Among inpatients, ARB (n = 1,164) and ACEI (n = 2,014) users had 21.0 vs. 17.7 all-cause deaths, per 100 person-months (HR 1.13, 95%CI 0.93-1.38, median follow-up 30 days). CONCLUSIONS: This observational analysis supports continued ARB or ACEI use for patients already using these medications before SARS-CoV-2 infection. The novel beneficial association observed among outpatients between users of ARBs vs. ACEIs on hospitalization or mortality should be confirmed with randomized trials.

Renin-angiotensin system blockade in the COVID-19 pandemic.

In the early months of the coronavirus disease 2019 (COVID-19) pandemic, a hypothesis emerged suggesting that pharmacologic inhibitors of the renin-angiotensin system (RAS) may increase COVID-19 severity. This hypothesis was based on the role of angiotensin-converting enzyme 2 (ACE2), a counterregulatory component of the RAS, as the binding site for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), allowing viral entry into host cells. Extrapolations from prior evidence led to speculation that upregulation of ACE2 by RAS blockade may increase the risk of adverse outcomes from COVID-19. However, counterarguments pointed to evidence of potential protective effects of ACE2 and RAS blockade with regard to acute lung injury, as well as substantial risks from discontinuing these commonly used and important medications. Here we provide an overview of classic RAS physiology and the crucial role of ACE2 in systemic pathways affected by COVID-19. Additionally, we critically review the physiologic and epidemiologic evidence surrounding the interactions between RAS blockade and COVID-19. We review recently published trial evidence and propose important future directions to improve upon our understanding of these relationships.

Continuation versus discontinuation of renin-angiotensin system inhibitors in patients admitted to hospital with COVID-19: a prospective, randomised, open-label trial.

BACKGROUND: Biological considerations suggest that renin-angiotensin system inhibitors might influence the severity of COVID-19. We aimed to evaluate whether continuing versus discontinuing renin-angiotensin system inhibitors (angiotensin-converting enzyme inhibitors or angiotensin receptor blockers) affects outcomes in patients admitted to hospital with COVID-19. METHODS: The REPLACE COVID trial was a prospective, randomised, open-label trial done at 20 large referral hospitals in seven countries worldwide. Eligible participants were aged 18 years and older who were admitted to hospital with COVID-19 and were receiving a renin-angiotensin system inhibitor before admission. Individuals with contraindications to continuation or discontinuation of renin-angiotensin system inhibitor therapy were excluded. Participants were randomly assigned (1:1) to continuation or discontinuation of their renin-angiotensin system inhibitor using permuted block randomisation, with allocation concealed using a secure web-based randomisation system. The primary outcome was a global rank score in which participants were ranked across four hierarchical tiers incorporating time to death, duration of mechanical ventilation, time on renal replacement or vasopressor therapy, and multiorgan dysfunction during the hospitalisation. Primary analyses were done in the intention-to-treat population. The REPLACE COVID trial is registered with ClinicalTrials.gov, NCT04338009. FINDINGS: Between March 31 and Aug 20, 2020, 152 participants were enrolled and randomly assigned to either continue or discontinue renin-angiotensin system inhibitor therapy (continuation group n=75; discontinuation group n=77). Mean age of participants was 62 years (SD 12), 68 (45%) were female, mean body-mass index was 33 kg/m2 (SD 8), and 79 (52%) had diabetes. Compared with discontinuation of renin-angiotensin system inhibitors, continuation had no effect on the global rank score (median rank 73 [IQR 40-110] for continuation vs 81 [38-117] for discontinuation; ß-coefficient 8 [95% CI -13 to 29]). There were 16 (21%) of 75 participants in the continuation arm versus 14 (18%) of 77 in the discontinuation arm who required intensive care unit admission or invasive mechanical ventilation, and 11 (15%) of 75 participants in the continuation group versus ten (13%) of 77 in the discontinuation group died. 29 (39%) participants in the continuation group and 28 (36%) participants in the discontinuation group had at least one adverse event (χ2 test of adverse events between treatment groups p=0·77). There was no difference in blood pressure, serum potassium, or creatinine during follow-up across the two groups. INTERPRETATION: Consistent with international society recommendations, renin-angiotensin system inhibitors can be safely continued in patients admitted to hospital with COVID-19. FUNDING: REPLACE COVID Investigators, REPLACE COVID Trial Social Fundraising Campaign, and FastGrants.

Randomized elimination and prolongation of ACE inhibitors and ARBs in coronavirus 2019 (REPLACE COVID) Trial Protocol.

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus responsible for coronavirus disease 2019 (COVID-19), is associated with high incidence of multiorgan dysfunction and death. Angiotensin-converting enzyme 2 (ACE2), which facilitates SARS-CoV-2 host cell entry, may be impacted by angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), two commonly used antihypertensive classes. In a multicenter, international randomized controlled trial that began enrollment on March 31, 2020, participants are randomized to continuation vs withdrawal of their long-term outpatient ACEI or ARB upon hospitalization with COVID-19. The primary outcome is a hierarchical global rank score incorporating time to death, duration of mechanical ventilation, duration of renal replacement or vasopressor therapy, and multiorgan dysfunction severity. Approval for the study has been obtained from the Institutional Review Board of each participating institution, and all participants will provide informed consent. A data safety monitoring board has been assembled to provide independent oversight of the project.

Thrombosis in COVID-19.

Thrombotic complications are frequent in COVID-19 and contribute significantly to mortality and morbidity. We review several mechanisms of hypercoagulability in sepsis that may be upregulated in COVID-19. These include immune-mediated thrombotic mechanisms, complement activation, macrophage activation syndrome, antiphospholipid antibody syndrome, hyperferritinemia, and renin-angiotensin system dysregulation. We highlight biomarkers within each pathway with potential prognostic value in COVID-19. Lastly, recent observational studies have evaluated a role for the expanded use of therapeutic anticoagulation in COVID-19. We review strengths and weaknesses of these studies, and we also discuss the hypothetical benefit and anticipated challenges of fibrinolytic therapy in COVID-19.

Coronavirus Disease 2019 and Hypertension: The Role of Angiotensin-Converting Enzyme 2 and the Renin-Angiotensin System.

Hypertension emerged from early reports as a potential risk factor for worse outcomes for persons with coronavirus disease 2019 (COVID-19). Among the putative links between hypertension and COVID-19 is a key counter-regulatory component of the renin-angiotensin system (RAS): angiotensin-converting enzyme 2 (ACE2). ACE2 facilitates entry of severe acute respiratory syndrome coronavirus 2, the virus responsible for COVID-19, into host cells. Because RAS inhibitors have been suggested to increase ACE2 expression, health-care providers and patients have grappled with the decision of whether to discontinue these medications during the COVID-19 pandemic. However, experimental models of analogous viral pneumonias suggest RAS inhibitors may exert protective effects against acute lung injury. We review how RAS and ACE2 biology may affect outcomes in COVID-19 through pulmonary and other systemic effects. In addition, we briefly detail the data for and against continuation of RAS inhibitors in persons with COVID-19 and summarize the current consensus recommendations from select specialty organizations.

Relationship Between ACE2 and Other Components of the Renin-Angiotensin System.

PURPOSE OF THE REVIEW: Angiotensin-converting enzyme 2 (ACE2) is a key counter-regulatory component of the renin-angiotensin system. Here, we briefly review the mechanistic and target organ effects related to ACE2 activity, and the importance of ACE2 in SARS-CoV-2 infection. RECENT FINDINGS: ACE2 converts angiotensin (Ang) II to Ang-(1-7), which directly opposes the vasoconstrictive, proinflammatory, and prothrombotic effects of Ang II. ACE2 also facilitates SARS-CoV-2 viral entry into host cells. Drugs that interact with the renin-angiotensin system may impact ACE2 expression and COVID-19 pathogenesis; however, the magnitude and direction of these effects are unknown at this time. High quality research is needed to improve our understanding of how agents that act on the renin-angiotensin system impact ACE2 and COVID-19-related disease outcomes.

Is There an Association Between COVID-19 Mortality and the Renin-Angiotensin System? A Call for Epidemiologic Investigations.

Mortality from coronavirus disease 2019 (COVID-19) is strongly associated with cardiovascular disease, diabetes, and hypertension. These disorders share underlying pathophysiology related to the renin-angiotensin system (RAS) that may be clinically insightful. In particular, activity of the angiotensin-converting enzyme 2 (ACE2) is dysregulated in cardiovascular disease, and this enzyme is used by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) to initiate the infection. Cardiovascular disease and pharmacologic RAS inhibition both increase ACE2 levels, which may increase the virulence of SARS-CoV-2 within the lung and heart. Conversely, mechanistic evidence from related coronaviruses suggests that SARS-CoV-2 infection may downregulate ACE2, leading to toxic overaccumulation of angiotensin II that induces acute respiratory distress syndrome and fulminant myocarditis. RAS inhibition could mitigate this effect. With conflicting mechanistic evidence, we propose key clinical research priorities necessary to clarify the role of RAS inhibition in COVID-19 mortality that could be rapidly addressed by the international research community.