Remdesivir-associated bradycardia in COVID-19: a rapid review protocol

INTRODUCTION

Remdesivir is an antiviral medication that is used in the treatment of severe COVID-19. Research has highlighted the potential cardiac side effects of remdesivir, including the occurrence of remdesivir-associated bradycardia (RAB), but these findings have not been consistent. In addition, very little is known about the clinical implications and outcomes of RAB. The aim of this rapid systematic review is to determine the event rate of developing bradycardia while receiving remdesivir treatment compared with not receiving remdesivir in patients diagnosed with COVID-19.

METHODS AND ANALYSIS

This study follows the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocol guidelines and will include original papers related to COVID-19, remdesivir and bradycardia. Only English language papers published from 1 December 2019 to 31 December 2022 will be included. The following databases will be searched using keywords and controlled vocabulary: Ovid MEDLINE, Ovid EMBASE, Scopus, Cochrane, PubMed and Web of Science. Two reviewers will independently perform screening and data abstraction. Data will be synthesised qualitatively as well as quantitatively. A random-effects model will be used to calculate the pooled estimates.

ETHICS AND DISSEMINATION

This review will systematically analyse the clinical studies available to help better characterise RAB. The results will support a retrospective study investigating RAB that is currently being conducted at the University Medical Center of Southern Nevada in Las Vegas, Nevada.

PROSPERO REGISTRATION NUMBER

This protocol has been submitted to and approved by PROSPERO (Protocol ID: CRD42022331614).

Clinical Characteristics and Implications of Bradycardia in COVID-19 Patients Treated with Remdesivir: A Single-Center Retrospective Cohort Study

Background and Objectives

Remdesivir is an antiviral drug used to treat coronavirus disease 2019 (COVID-19) with a relatively obscure cardiac effect profile. Previous studies have reported bradycardia associated with remdesivir, but few have examined its clinical characteristics. The objective of this study was to investigate remdesivir associated bradycardia and its associated clinical characteristics and outcomes.

Methods

This is a single-institution retrospective study that investigated bradycardia in 600 patients who received remdesivir for treatment of COVID-19. A total of 375 patients were included in the study after screening for other known causes of bradycardia (atrioventricular [AV] nodal blockers). All patients were analyzed for episodes of bradycardia from when remdesivir was initiated up to 5 days after completion, a time frame based on the drug’s putative elimination half-life. Univariate and multivariate statistical tests were conducted to analyze the data.

Results

The mean age of the sample was 56.63 ± 13.23 years. Of patients who met inclusion criteria, 49% were found to have bradycardia within 5 days of remdesivir administration. Compared to the cohort without a documented bradycardic episode, patients with bradycardia were significantly more likely to experience inpatient mortality (22% vs 12%, p = 0.01). The patients with bradycardia were found to have marginally higher serum D-dimer levels (5.2 vs 3.4 µg/mL, p = 0.05) and were more likely to undergo endotracheal intubation (28% vs 14%, p = 0.008). Male sex, hyperlipidemia, and bradycardia within 5 days of completing remdesivir were significant predictors of inpatient mortality. No significant differences in length of stay were found.

Conclusions

Bradycardia that occurs during or shortly after remdesivir treatment in COVID-19 patients may be associated with an increased rate of in-hospital mortality. However, COVID-19 and its cardiac complications cannot be excluded as potential contributors of bradycardia in the present study. Future studies are needed to further delineate the cardiac characteristics of COVID-19 and remdesivir.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40261-022-01187-x.

Comorbid neuropathological diagnoses in early versus late-onset Alzheimer's disease

Copathologies play an important role in the expression of the AD clinical phenotype and may influence treatment efficacy. Early-onset AD (EOAD), defined as manifesting before age 65, is viewed as a relatively pure form of AD with a more homogeneous neuropathological substrate. We sought to compare the frequency of common neuropathological diagnoses in a consecutive autopsy series of 96 patients with EOAD (median age of onset = 55 years, 44 females) and 48 with late-onset AD (LOAD) (median age of onset = 73 years, 14 females). The UCSF Neurodegenerative Disease Brain Bank database was reviewed to identify patients with a primary pathological diagnosis of AD. Prevalence and stage of Lewy body disease (LBD), limbic age-related TDP-43 encephalopathy (LATE), argyrophilic grain disease (AGD), hippocampal sclerosis (HS), cerebral amyloid angiopathy (CAA), and vascular brain injury (VBI) were compared between the two cohorts. We found at least one non-AD pathological diagnosis in 98% of patients with EOAD (versus 100% of LOAD), and the number of comorbid diagnoses per patient was lower in EOAD than in LOAD (median=2 versus 3, Mann-Whitney Z = 3.00, p = 0.002). LBD and CAA were common in both EOAD and LOAD (CAA: 86% versus 79%, Fisher exact p = 0.33; LBD: 49% versus 42%, p = 0.48, respectively), although amygdala-predominant LBD was more commonly found in EOAD than LOAD (22% versus 6%, p = 0.02). In contrast, LATE (35% versus 8%, p < 0.001), HS (15% versus 3%, p = 0.02), AGD (58% versus 41%, p = 0.052), and VBI (65% versus 39%, p = 0.004) were more common in LOAD than EOAD, respectively. The number of copathologies predicted worse cognitive performance at the time of death on MMSE (1.4 points/pathology (95%CI [-2.5, -0.2]) and Clinical Dementia Rating - Sum of Boxes (1.15 point/pathology, 95%CI [0.45, 1.84]), across the EOAD and the LOAD cohorts. The effect of sex on the number of copathologies was not significant (p = 0.17). Prevalence of at least one APOE ε4 allele was similar across the two cohorts (52% and 54%) and was associated with a greater number of copathologies (+0.40, 95%CI [0.01, 0.79], p = 0.047), independent of age of symptom onset, sex, and disease duration. Females showed higher density of neurofibrillary tangles compared to men, controlling for age of onset, APOE ε4, and disease duration. Our findings suggest that non-AD pathological diagnoses play an important role in the clinical phenotype of EOAD with potentially significant implications for clinical practice and clinical trials design.

Profound degeneration of wake-promoting neurons in Alzheimer's disease

INTRODUCTION

Sleep-wake disturbances are a common and early feature in Alzheimer's disease (AD). The impact of early tau pathology in wake-promoting neurons (WPNs) remains unclear.

METHODS

We performed stereology in postmortem brains from AD individuals and healthy controls to identify quantitative differences in morphological metrics in WPNs. Progressive supranuclear palsy (PSP) and corticobasal degeneration were included as disease-specific controls.

RESULTS

The three nuclei studied accumulate considerable amounts of tau inclusions and showed a decrease in neurotransmitter-synthetizing neurons in AD, PSP, and corticobasal degeneration. However, substantial neuronal loss was exclusively found in AD.

DISCUSSION

WPNs are extremely vulnerable to AD but not to 4 repeat tauopathies. Considering that WPNs are involved early in AD, such degeneration should be included in the models explaining sleep-wake disturbances in AD and considered when designing a clinical intervention. Sparing of WPNs in PSP, a condition featuring hyperinsomnia, suggest that interventions to suppress the arousal system may benefit patients with PSP.

Mitochondrial targeting of XJB-5-131 attenuates or improves pathophysiology in HdhQ150 animals with well-developed disease phenotypes

Oxidative damage to mitochondria (MT) is a major mechanism for aging and neurodegeneration. We have developed a novel synthetic antioxidant, XJB-5-131, which directly targets MT, the primary site and primary target of oxidative damage. XJB-5-131 prevents the onset of motor decline in an HdhQ(150/150) mouse model for Huntington's disease (HD) if treatment starts early. Here, we report that XJB-5-131 attenuates or reverses disease progression if treatment occurs after disease onset. In animals with well-developed pathology, XJB-5-131 promotes weight gain, prevents neuronal death, reduces oxidative damage in neurons, suppresses the decline of motor performance or improves it, and reduces a graying phenotype in treated HdhQ(150/150) animals relative to matched littermate controls. XJB-5-131 holds promise as a clinical candidate for the treatment of HD.