Bebtelovimab, alone or together with bamlanivimab and etesevimab, as a broadly neutralizing monoclonal antibody treatment for mild to moderate, ambulatory COVID-19

BACKGROUNDBebtelovimab is a potent, fully human IgG1 monoclonal antibody (mAb) targeting the S-protein of SARS-CoV-2, with broad neutralizing activity to all currently known SARS-CoV-2 variants of concern, including omicron variant lineages. Specialized developmental approaches accelerated the initiation of a clinical trial designed to evaluate the efficacy and safety of bebtelovimab alone (BEB) or together with bamlanivimab (BAM) and etesevimab (ETE) delivered via slow intravenous push for the treatment of mild-to-moderate COVID-19. METHODSThis portion of the phase 2, BLAZE-4 trial (J2X-MC-PYAH; NCT04634409) enrolled 714 patients (between May and July 2021) with mild-to-moderate COVID-19 within 3 days ([≤]3 days) of laboratory diagnosis of SARS-CoV-2 infection. Patients at low risk for severe COVID-19 were randomized 1:1:1 (double-blinded) to placebo, BEB 175 mg, or BEB 175 mg+BAM 700 mg+ETE 1400 mg (BEB+BAM+ETE). Patients at high risk for progression to severe COVID-19 were randomized 2:1 (open-label) to BEB or BEB+BAM+ETE, and a subsequent treatment arm enrolled patients to BEB+BAM+ETE using Centers for Disease Control and Prevention (CDC) updated criteria for High-risk. All treatments were administered intravenously over [≥]30 seconds (open-label BEB) or [≥]6.5 minutes (all other treatment arms). For the placebo-controlled patients (termed Low-risk), the primary endpoint was the proportion of patients with persistently high viral load (PHVL) (log viral load >5.27) on Day 7. For the open-label patients (termed High-risk), the primary endpoint was safety. In nonclinical studies, SARS-CoV-2 isolates were tested using an endpoint neutralization assay to measure BEBs inhibitory concentration greater than 99% (IC99). RESULTSBaseline viral sequencing data were available from 611 patients; 90.2% (n=551) aligned with a variant of interest or concern (WHO designation), with the majority infected with delta (49.8%) or alpha (28.6%) variants. Among the Low-risk patients, PHVL occurred in 19.8% of patients treated with placebo, as compared to 12.7% (p=0.132) of patients treated with BEB+BAM+ETE and 12.0% (p=0.097) of patients treated with BEB, a 36% and 40% relative risk reduction, respectively. Viral load-area under the curve analysis from baseline to Day 11 showed statistically signficant reductions for patients treated with BEB (p=0.006) and BEB+BAM+ETE (p=0.043) compared to patients who received placebo. Time to sustained symptom resolution was reduced by a median of 2 days for patients treated with BEB (6 days; p=0.003) and 1 day for patients treated with BEB+BAM+ETE (7 days; p=0.289) compared to placebo (8 days). The incidence of COVID-19-related hospitalization or all-cause deaths by day 29 were similar across treatment arms, as expected given the patients risk status (the Low risk cohorts had a Low risk of hospitalization, and High risk cohorts received only active therapy without placebo). Overall, safety results were consistent with previous studies investigating mAbs targeting SARS-CoV-2. The proportion of patients with treatment emergent adverse events (AEs) were 9.7% in Low-risk (n=37/380) and 14.7% in High-risk (n=48/326) patients treated with BEB or BEB+BAM+ETE; majority of AEs were considered mild or moderate in severity. Serious AEs were reported in 2.1% of High-risk patients (n=7/326), including one death (a cerebrovascular accident); 1 serious AE was reported among Low-risk patients. In an in vitro neutralization assay, BEB neutralized the omicron isolate (BA.1) with <2.44ng/ml estimated IC99. CONCLUSIONSIn patients with mild-to-moderate COVID-19, treatment with BEB or BEB+BAM+ETE was associated with greater viral clearance, a reduction in time to sustained symptom resolution, and safety results consistent with mAbs that target SARS-CoV-2. Integration of clinical findings with in vitro neutralization of emerging viral variants offered a pragmatic framework for investigating the efficacy of a new antiviral mAb agent, as demonstrated by bebtelovimab.

Short-term and Long-term Risk of Stroke in Patients With Perioperative Atrial Fibrillation After Cardiac Surgery: Systematic Review and Meta-analysis.

BACKGROUND: Perioperative atrial fibrillation (POAF) after cardiac surgery has been associated with an increased risk of stroke in some studies. However, the exact magnitude of this association during short-term and long-term follow-up remains unclear. METHODS: We searched PubMed, Embase, and Cochrane Central Register of Controlled Trials (CENTRAL) for the time period from database inception to October 2020. We included observational studies with ≥ 100 patients that reported data on short-term or long-term stroke risk in patients with and without POAF after cardiac surgery. Data were pooled using random-effects models. We reported summary risk ratios (RRs) for studies reporting multivariable adjusted results and calculated absolute risk differences (ARDs) with 95% confidence intervals (CIs). RESULTS: A total of 55 studies with 540,209 patients were included. POAF was associated with both an increased relative risk (RR 1.69; 95% CI, 1.41-2.03; I2 = 82%; 9 studies) and absolute risk of short-term stroke (4.5% vs 2.5%; ARD 2.0%; 95% CI, 1.28-2.89). POAF was associated with an increased relative risk (RR 1.20; 95% CI, 1.12-1.29; I2 = 16%; 10 studies) and absolute risk of long-term stroke (1.06 vs 0.88 per 100 patient-years; ARD 0.18 per 100 patient-years; 95% CI, 0.07-0.26). Sensitivity analyses of high-quality studies and studies reporting either ischemic or embolic strokes yielded similar findings. CONCLUSIONS: POAF after cardiac surgery was associated with an increased risk of both short-term and long-term stroke. However, the long-term stroke ARD was small, and whether these patients will benefit from long-term oral anticoagulation therapy is unclear.

CONTEXTE: La fibrillation auriculaire périopératoire (FAPO) après une chirurgie cardiaque a été associée à un risque accru d'accident vasculaire cérébral (AVC) dans certaines études. Cependant, l'ampleur exacte de cette association durant le suivi à court et à long terme reste incertaine. MÉTHODOLOGIE: Nous avons effectué des recherches dans les bases de données PubMed, Embase et CENTRAL (Cochrane Central Register of Controlled Trials) pour la période allant de la création de ces bases à octobre 2020. Nous avons inclus des études d'observation comptant ≥ 100 patients et rapportant des données sur le risque d'AVC à court ou à long terme chez les patients ayant présenté ou non une FAPO après une chirurgie cardiaque. Les données ont été regroupées à l'aide de modèles à effets aléatoires. Nous avons consigné les rapports de risque (RR) sommaires pour les études rapportant des résultats corrigés multivariables et calculé les différences de risque absolu (DRA) avec des intervalles de confiance (IC) à 95 %. RÉSULTATS: Au total, 55 études portant sur 540 209 patients ont été incluses. La FAPO était associée à une augmentation tant du risque relatif (RR : 1,69; IC à 95 % : 1,41 à 2,03; I2 = 82 %; 9 études) que du risque absolu d'AVC à court terme (4,5 % vs 2,5 %; DRA : 2,0 %; IC à 95 % : 1,28 à 2,89). La FAPO était également associée à une augmentation du risque relatif (RR : 1,20; IC à 95 % : 1,12 à 1,29; I2 = 16 %; 10 études) et du risque absolu d'AVC à long terme (1,06 vs 0,88 par 100 années-patients; DRA : 0,18 par 100 années-patients; IC à 95 % : 0,07 à 0,26). Les analyses de sensibilité des études de haute qualité et des études rapportant des AVC ischémiques ou emboliques ont donné des résultats similaires. CONCLUSIONS: La FAPO après une chirurgie cardiaque a été associée à un risque accru d'AVC à court et à long terme. Cependant, comme la différence de risque absolu d'AVC à long terme était faible, la possibilité qu'une anticoagulothérapie orale à long terme soit bénéfique pour ces patients est incertaine.

Cell type-specific immune dysregulation in severely ill COVID-19 patients

Coronavirus disease 2019 (COVID-19) has quickly become the most serious pandemic since the 1918 flu pandemic. In extreme situations, patients develop a dysregulated inflammatory lung injury called acute respiratory distress syndrome (ARDS) that causes progressive respiratory failure requiring mechanical ventilatory support. Recent studies have demonstrated immunologic dysfunction in severely ill COVID-19 patients. To further delineate the dysregulated immune response driving more severe clinical course from SARS-CoV-2 infection, we used single-cell RNA sequencing (scRNAseq) to analyze the transcriptome of peripheral blood mononuclear cells (PBMC) from hospitalized COVID-19 patients having mild disease (n = 5), developing ARDS (n = 6), and recovering from ARDS (n = 6). Our data demonstrated an overwhelming inflammatory response with select immunodeficiencies within various immune populations in ARDS patients. Specifically, their monocytes had defects in antigen presentation and deficiencies in interferon responsiveness that contrasted the higher interferon signals in lymphocytes. Furthermore, cytotoxic activity was suppressed in both NK and CD8 lymphocytes whereas B cell activation was deficient, which is consistent with the delayed viral clearance in severely ill COVID-19 patients. Finally, we identified altered signaling pathways in the severe group that suggests immunosenescence and immunometabolic changes could be contributing to the dysfunctional immune response. Our study demonstrates that COVID-19 patients with ARDS have an immunologically distinct response when compared to those with a more innocuous disease course and show a state of immune imbalance in which deficiencies in both the innate and adaptive immune response may be contributing to a more severe disease course in COVID-19.

Pre-Existing Characteristics Associated with Covid-19 Illness Severity

BackgroundCertain individuals, when infected by SARS-CoV-2, tend to develop the more severe forms of Covid-19 illness for reasons that remain unclear. MethodsWe studied N=442 patients who presented with laboratory confirmed Covid-19 illness to our U.S. metropolitan healthcare system. We curated data from the electronic health record, and used multivariable logistic regression to examine the association of pre-existing traits with a Covid-19 illness severity defined by level of required care: need for hospital admission, need for intensive care, and need for intubation. ResultsOf all patients studied, 48% required hospitalization, 17% required intensive care, and 12% required intubation. In multivariable-adjusted analyses, patients requiring a higher levels of care were more likely to be older (OR 1.5 per 10 years, P<0.001), male (OR 2.0, P=0.001), African American (OR 2.1, P=0.011), obese (OR 2.0, P=0.021), with diabetes mellitus (OR 1.8, P=0.037), and with a higher comorbidity index (OR 1.8 per SD, P<0.001). Several clinical associations were more pronounced in younger compared to older patients (Pinteraction<0.05). Of all hospitalized patients, males required higher levels of care (OR 2.5, P=0.003) irrespective of age, race, or morbidity profile. ConclusionsIn our healthcare system, greater Covid-19 illness severity is seen in patients who are older, male, African American, obese, with diabetes, and with greater overall comorbidity burden. Certain comorbidities paradoxically augment risk to a greater extent in younger patients. In hospitalized patients, male sex is the main determinant of needing more intensive care. Further investigation is needed to understand the mechanisms underlying these findings.

The use of dispatcher assistance in improving the quality of cardiopulmonary resuscitation: A randomised controlled trial.

AIMS: The introduction of dispatcher assistance (DA) services has led to increased bystander cardiopulmonary resuscitation (CPR) participation rates. However, the extent to which DA improves CPR quality remains unclear. This study aimed to evaluate the efficacy of DA in improving CPR quality among healthcare professionals and laypersons within a multi-ethnic Southeast Asian population. METHODS: A parallel, randomised controlled, open label trial was performed. Four hundred and twelve participants were recruited via convenience sampling in a public location. In a simulated cardiac-arrest scenario, the participants were randomised to perform CPR with DA over the phone (DA+) or CPR without DA (DA-). The ratio of participant assignment to DA+ and DA- was 1:1. The primary outcomes were CPR compression depth, compression rate, no-flow time, complete release of pressure between compressions, and hand location. The assessment involved CPR manikins and human assessors. RESULTS: A larger proportion of participants in DA + achieved the correct compression rate (34.3% vs 18.1%, p < 0.001). There was no difference in the other primary outcomes. A subgroup analysis revealed that healthcare professionals in DA+ had a higher proportion of correct hand location compared to those in DA- (82.1% vs. 53.5%, p < 0.05). There was no significant difference in CPR quality among laypersons with valid CPR certification regardless of whether they received DA. CONCLUSION: DA should be provided to laypersons without valid CPR certification, as well as healthcare professionals. The identification of gaps in the current DA protocol highlights areas where specific changes can be made to improve CPR quality.