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.

1153. Safety and Potential Efficacy of Exosomes Overexpressing CD24 (EXO-CD24) for the Prevention of Clinical Deterioration in Patients with Moderate or Severe COVID-19: A Phase II, Randomized, Single-blinded Study

Background

EXO-CD24 is a novel inhaled drug of exosomes displaying CD24, a protein with anti-inflammatory properties. We evaluated the safety and potential efficacy of EXO-CD24, in a phase II, randomized, single-blinded clinical trial of EXO-CD24 in hospitalized patients with moderate or severe COVID-19, following the preliminary safety and efficacy results of a phase 1 study (ClinicalTrials.gov: NCT04747574).

Methods

Two tertiary care hospitals in Athens, Greece participated. Patients received either 10⁹ or 10¹⁰ exosome particles per dose, once per day for 5 days and were followed for 28 days. Safety and efficacy measures (including respiratory rate < 23 b/min and pulse oximetry SpO₂≥ 94% on room air, oxygen need and levels of inflammatory biomarkers i.e. CRP, LDH, ferritin, fibrinogen and d-dimers) were compared between groups at days 3, 5 and 7. A separate analysis was conducted comparing the clinical course of treated patients with that of a control cohort (n=70 patients) matched by propensity scoring out of a similar period hospitalized cohort (n=202) that did not participate in the study.

Results

Between June 9th and August 3rd 2021, 91 patients underwent randomization: 45 in group A and 46 in group B (10⁹vs. 10¹⁰ exosome particles per dose). Mean age was 49.4 (± 13.2) years and 74.4% were male. Mean time from symptom onset to randomization was 8 days. Improvement in respiratory rate and pulse oximetry was noted in 72 out of 86 (83.7%) and 55 out of 86 (64%) analyzed patients. Day 7 inflammatory indices levels dropped at least 50% from baseline admission values in 72 out of 86 (82.8%) analyzed patients (p< 0.001). No treatment-related adverse events were reported. Comparison with the propensity score matched group showed statistically significant differences in the same parameters (p≤ 0.01 for all comparisons).

Conclusion

Our results suggest safety and potential efficacy of EXO-CD24 on clinical and laboratory parameters of moderate or severe COVID-19, that deserve further investigation in a phase 3 study. (Funded by Athens Medical Society. ClinicalTrials.gov: NCT04902183, EU Clinical Trials Register EudraCT Number 2021-002184-22).

Disclosures

All Authors: No reported disclosures.

Ribavirin aerosol in hospitalized adults with respiratory distress and COVID-19: An open-label trial

There is an unmet medical need for effective treatments for hospitalized patients with coronavirus disease 2019 (COVID-19). Ribavirin is a broad-spectrum antiviral with demonstrated in vitro activity against multiple viruses, including severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). This trial evaluated the potential of ribavirin inhalation solution (ribavirin aerosol) to reduce COVID-19 disease severity in adults with confirmed SARS-CoV-2 infection and a diagnosis of respiratory distress. This phase I, multicenter, open-label, nonrandomized trial was conducted from February 2021 through August 2021. Patients received ribavirin aerosol (100 mg/ml for 30 min or 50 mg/ml for 60 min) twice daily for up to 6 days. The primary end point was change from baseline in clinical status severity, rated on a 7-point scale (1 [death]; 7 [not hospitalized; no limitations on activities]), at day 7 (or end-of-treatment/early termination) and day 30 (follow-up). Fifty-one patients were treated with ribavirin aerosol (mean age, 51.5 years; 78.4% men); mean number of doses was 9.7 (range, 1-12). Improvement of ≥1 level in clinical status severity was observed in 31.4% (16/51) and 78.4% (40/51) of patients at end-of-treatment and day 30, respectively. Of 21 patients who required a ventilator, 16 (76.2%) were able to discontinue ventilator use. Five patients (9.8%) died between end-of-treatment and day 30. Three patients (5.9%) discontinued study treatment due to adverse events. No deaths were considered related to study treatment. These data provide preliminary evidence that ribavirin aerosol may be an efficacious treatment for respiratory distress in adults with COVID-19.

Efficacy and Safety of Ensovibep for Adults Hospitalized With COVID-19 : A Randomized Controlled Trial

BACKGROUND

Ensovibep (MP0420) is a designed ankyrin repeat protein, a novel class of engineered proteins, under investigation as a treatment of SARS-CoV-2 infection.

OBJECTIVE

To investigate if ensovibep, in addition to remdesivir and other standard care, improves clinical outcomes among patients hospitalized with COVID-19 compared with standard care alone.

DESIGN

Double-blind, randomized, placebo-controlled, clinical trial. (ClinicalTrials.gov: NCT04501978).

SETTING

Multinational, multicenter trial.

PARTICIPANTS

Adults hospitalized with COVID-19.

INTERVENTION

Intravenous ensovibep, 600 mg, or placebo.

MEASUREMENTS

Ensovibep was assessed for early futility on the basis of pulmonary ordinal scores at day 5. The primary outcome was time to sustained recovery through day 90, defined as 14 consecutive days at home or place of usual residence after hospital discharge. A composite safety outcome that included death, serious adverse events, end-organ disease, and serious infections was assessed through day 90.

RESULTS

An independent data and safety monitoring board recommended that enrollment be halted for early futility after 485 patients were randomly assigned and received an infusion of ensovibep (n = 247) or placebo (n = 238). The odds ratio (OR) for a more favorable pulmonary outcome in the ensovibep (vs. placebo) group at day 5 was 0.93 (95% CI, 0.67 to 1.30; P = 0.68; OR > 1 would favor ensovibep). The 90-day cumulative incidence of sustained recovery was 82% for ensovibep and 80% for placebo (subhazard ratio [sHR], 1.06 [CI, 0.88 to 1.28]; sHR > 1 would favor ensovibep). The primary composite safety outcome at day 90 occurred in 78 ensovibep participants (32%) and 70 placebo participants (29%) (HR, 1.07 [CI, 0.77 to 1.47]; HR < 1 would favor ensovibep).

LIMITATION

The trial was prematurely stopped because of futility, limiting power for the primary outcome.

CONCLUSION

Compared with placebo, ensovibep did not improve clinical outcomes for hospitalized participants with COVID-19 receiving standard care, including remdesivir; no safety concerns were identified.

PRIMARY FUNDING SOURCE

National Institutes of Health.

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.

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.