The safety and potential efficacy of exosomes overexpressing CD24 (EXO-CD24) in mild-moderate COVID-19 related ARDS.

INTRODUCTION: EXO-CD24 are exosomes genetically manipulated to over-express Cluster of Differentiation (CD) 24. It consists of two breakthrough technologies: CD24, the drug, as a novel immunomodulator that is smarter than steroids without any side effects, and exosomes as the ideal natural drug carrier. METHODS: A randomized, single blind, dose-finding phase IIb trial in hospitalized patients with mild to moderate Coronavirus disease 2019 (COVID-19) related Acute Respiratory Distress Syndrome (ARDS) was carried out in two medical centers in Athens. Patients received either 109 or 1010 exosome particles of EXO-CD24, daily, for five consecutive days and monitored for 28 days. Efficacy was assessed at day 7 among 91 patients who underwent randomization. The outcome was also compared in a post-hoc analysis with an income control group (n = 202) that fit the inclusion and exclusion criteria. RESULTS: The mean age was 49.4 (± 13.2) years and 74.4% were male. By day 7, 83.7% showed improved respiratory signs and 64% had better oxygen saturation (SpO2) (p < 0.05). There were significant reductions in all inflammatory markers, most notably in C-reactive protein (CRP), lactate dehydrogenase (LDH), ferritin, fibrinogen and an array of cytokines. Conversely, levels of the anti-inflammatory cytokine Interleukin-10 (IL-10) were increased (p < 0.05). Of all the documented adverse events, none were considered treatment related. No drug-drug interactions were noted. Two patients succumbed to COVID-19. Post-hoc analysis revealed that EXO-CD24 patients exhibited greater improvements in clinical and laboratory outcomes compared to an observational income control group. CONCLUSIONS: EXO-CD24 presents a promising therapeutic approach for hyper-inflammatory state and in particular ARDS. Its unique combination of exosomes, as a drug carrier, and CD24, as an immunomodulator, coupled with inhalation administration, warrants further investigation in a larger, international, randomized, quadri-blind trial against a placebo.

Early Occurrence of Adverse Events in Hospitalized Patients With COVID-19 and Beneficial Effect of Anticoagulation.

BACKGROUND/AIM: This study analyzed the characteristics of patients with COVID-19 with major events during the first days of hospitalization. PATIENTS AND METHODS: This is a retrospective analysis of prospectively collected data from consecutive patients admitted to two hospitals in Athens, Greece. The characteristics of patients with COVID-19 who suffered the primary endpoint (venous thromboembolic events, intubation, and death) during the first days of hospitalization were analyzed. RESULTS: Among 95 patients included in the analysis, 21 presented with major adverse events during a median follow-up of 13 days. More than 50% of these patients presented with a major event during the first 3 days. Anticoagulation treatment was inversely associated with the cumulative incidence of the primary endpoint [hazard ratio=0.16 (95% confidence interval=0.06-0.47)]. Patients with major events were older, with lower baseline SatO2, and higher number of Wells' criteria and Charlson comorbidity index. Among these patients, those with hypertension were at higher risk for early occurrence of events (≤ first three days of hospitalization). CONCLUSION: Major adverse events may occur early in hospitalized patients with COVID-19 with a high-risk profile. Anticoagulation treatment appears to reduce this risk and thus prompt thromboprophylaxis should be employed in these patients.

Comparative Immunogenicity of BNT162b2 mRNA Vaccine with Natural SARS-CoV-2 Infection.

BNT162b2 has proven to be highly effective, but there is a paucity of data regarding immunogenicity factors and comparison between response to vaccination and natural infection. This study included 871 vaccinated healthcare workers (HCW) and 181 patients with natural infection. Immunogenicity was assessed by measuring anti-SARS-CoV-2 against the RBD domain of the spike protein (anti-RBD). Samples were collected 1-2 weeks after vaccination or 15-59 days post-onset of symptoms. Post-vaccine anti-RBD concentrations were associated with age, gender, vaccination side-effects (VSE) and prior infection (Pr-CoV). Anti-RBD median levels (95%CI) were lower by 2466 (651-5583), 6228 (3254-9203) and 7651 (4479-10,823) AU/mL in 35-44, 45-54, 55-70 yrs, respectively, compared with the 18-34 yrs group. In females, the median levels were higher by 2823 (859-4787), 5024 (3122-6926) in individuals with VSE, and 9971 (5158-14,783) AU/mL in HCWs with Pr-CoV. The ratio of anti-RBD in vaccinated individuals versus those with natural infection varied from 1.0 to 19.4. The high immunogenicity of BNT162b2 is verified, although its sustainability has yet to be elucidated. The use of comparative data from natural infection serological panels, expressing the clinical heterogeneity of natural infection, may facilitate early decisions for candidate vaccines to be evaluated in clinical trials.

Knowledge and Perceptions about COVID-19 among Health Care Workers: Evidence from COVID-19 Hospitals during the Second Pandemic Wave.

Health care workers (HCWs) face a higher risk of infection, since they work at the front line of COVID-19 patients' management. Misinterpretations of current scientific evidence among HCWs may impact the delivery of appropriate care to COVID-19 patients and increase the risk of SARS-CoV-2 transmission in the hospital setting. Moreover, knowledge may affect HCWs perceptions depending on their broad beliefs and past experiences. The aim of this study was to explore the knowledge and perceptions of HCWs regarding COVID-19 issues during the second wave of the pandemic. A cross-sectional survey, involving a printed questionnaire, was conducted from 21 October 2020 to 31 January 2021 in four tertiary care hospitals located at four distant geographical regions in Greece. In total, 294 HCWs participated in this study. The majority of HCWs provided precise responses regarding general knowledge, perceptions, and practices concerning the COVID-19 pandemic. However, responses on hand hygiene and antimicrobial use in HCWs with COVID-19 were mistaken. This study reveals a certain degree of misconceptions and knowledge gaps in HCWs everyday practice, especially regarding hand hygiene and antimicrobial use in COVID-19 patients.

Beneficial Effects of Intermediate Dosage of Anticoagulation Treatment on the Prognosis of Hospitalized COVID-19 Patients: The ETHRA Study.

BACKGROUND/AIM: To investigate the efficacy (prognosis, coagulation/inflammation biomarkers) and safety (bleeding events) of different anticoagulation dosages in COVID-19 inpatients. PATIENTS AND METHODS: COVID-19 inpatients (Athens, Greece) were included. The "Enhanced dose THRomboprophylaxis in Admissions (ETHRA)" protocol was applied in certain Departments, suggesting the use of intermediate anticoagulation dosage. The primary endpoint was a composite of intubation/venous thromboembolism/death. Inflammation/coagulation parameters were assessed. RESULTS: Among 127 admissions, 95 fulfilled the inclusion criteria. Twenty-one events (4 deaths, 17 intubations) were observed. Regression analysis demonstrated significant reduction of events with intermediate or therapeutic dosage [HR=0.16 (95%CI=0.05-0.52) p=0.002; HR=0.17 (0.04-0.71) p=0.015, respectively]. D-Dimer values were higher in those who met the composite endpoint. Intermediate dosage treatment was associated with decreased values of ferritin. Three patients (3%) had minor hemorrhagic complications. CONCLUSION: Anticoagulation treatment (particularly intermediate dosage) appears to have positive impact on COVID-19 inpatients' prognosis by inhibiting both coagulation and inflammatory cascades.

Antibodies against SARS-CoV-2 among health care workers in a country with low burden of COVID-19.

INTRODUCTION: Greece is a country with limited spread of SARS-CoV-2 and cumulative infection attack rate of 0.12% (95% CI 0.06-0.26). Health care workers (HCWs) are a well-recognized risk group for COVID-19. The study aimed to estimate the seroprevalence of antibodies to SARS-CoV-2 in a nosocomial setting and assess potential risk factors. METHODS: HCWs from two hospitals participated in the study. Hospital-1 was a tertiary university affiliated center, involved in the care of COVID-19 patients while hospital-2 was a tertiary specialized cardiac surgery center not involved in the care of these patients. A validated, CE, rapid, IgM/IgG antibody point-of-care test was used. Comparative performance with a reference globally available assay was assessed. RESULTS: 1,495 individuals consented to participate (response rate 77%). The anti-SARS-CoV-2 weighted prevalence was 1.26% (95% CI 0.43, 3.26) overall and 0.53% (95% CI 0.06, 2.78) and 2.70% (95% CI 0.57, 9.19) in hospital-1 and hospital-2, respectively although the study was underpowered to detect statistically significant differences. The overall, hospital-1, and hospital-2 seroprevalence was 10, 4 and 22 times higher than the estimated infection attack rate in general population, respectively. Suboptimal use of personal protective equipment was noted in both hospitals. CONCLUSIONS: These data have implications for the preparedness of a second wave of COVID-19 epidemic, given the low burden of SARS-CoV-2 infection rate, in concordance with national projections.