Assessment of Safety and Prophylactic Efficacy of the EpiVacCorona Peptide Vaccine for COVID-19 Prevention (Phase III).

The State Research Center of Virology and Biotechnology "VECTOR" of the Federal Service for the Oversight of Consumer Protection and Welfare (Rospotrebnadzor) has developed the peptide-based EpiVacCorona vaccine, which is the first synthetic peptide-based antiviral vaccine for mass immunization in international vaccinology. An early clinical trial (Phase I-II) demonstrated that the EpiVacCorona vaccine is a safe product. The "Multicenter double-blind, placebo-controlled, comparative, randomized trial to assess the tolerability, safety, immunogenicity and prophylactic efficacy of the EpiVacCorona COVID-19 vaccine based on peptide antigens in 3000 volunteers aged 18 years and older" was performed regarding vaccine safety. The key objectives of the study were to evaluate the safety and prophylactic efficacy of the two-dose EpiVacCorona vaccine administered via the intramuscular route. The results of the clinical study (Phase III) demonstrated the safety of the EpiVacCorona vaccine. Vaccine administration was accompanied by mild local reactions in ≤27% of cases and mild systemic reactions in ≤14% of cases. The prophylactic efficacy of the EpiVacCorona COVID-19 vaccine after the completion of the vaccination series was 82.5% (CI95 = 75.3-87.6%). The high safety and efficacy of the vaccine give grounds for recommending this vaccine for regular seasonal prevention of COVID-19 as a safe and effective medicinal product.

Effect of Sulodexide on Circulating Blood Cells in Patients with Mild COVID-19.

BACKGROUND: Despite the fact that COVID-19 usually manifests with severe pneumonia, there is a growing body of evidence that life-threatening multiorgan damage is caused by vascular and hemostatic abnormalities. Since there is no established therapy, assessing antithrombotics is indeed important. Sulodexide, a compound derived from porcine intestinal mucosa is a mixture of fast-moving heparin fraction (80%) and dermatan sulfate (20%), is approved in Europe and currently in trials for COVID-19 indication. METHODS: This single-center, prospective, observational study included 28 patients with mild COVID-19 hospitalized in the Central Clinical Hospital of the Presidential Administration of the Russian Federation. Patients in the control group (n = 14) were treated using routine therapy according to current guidelines, while patients in the experimental group (n = 14) had the routine treatment supplemented with daily intravenous injections of sulodexide in 600-unit doses. Scanning electron microscopy was utilized to examine the blood specimens derived from the cubital vein at admission and at 10 days after hospitalization, which was approximately the average duration of patients' treatment in the hospital (11.6 ± 0.4 days). RESULTS: Sulodexide significantly (by 40%) diminished the score of circulating endothelial cells, potentially indicating its antiviral endothelium-protective properties. It also prevented the extra activation of the platelets and the formation of erythrocytic sludges. Among patients in the control group, the share of activated platelets rose from 37 ± 5% to 45 ± 6% (p = 0.04) over the course of the study period, whereas among patients in the experimental group, the share of activated platelets remained practically unchanged (43 ± 6% vs. 38 ± 4%, p = 0.22). The score of erythrocytic sludges in the control group remained practically the same (4.8 ± 1.1 at admission vs. 3.9 ± 0.9 after 10 days, p = 0.67), whereas in the experimental group, it significantly decreased (from 5.7 ± 1.7 to 2.4 ± 0.9, p = 0.03). CONCLUSIONS: Sulodexide is able to defend endothelium, normalize blood, and, seemingly, prevent thrombosis. Therefore, it may be considered as a promising and effective agent for the treatment of patients with mild COVID-19. Broader randomized trials are needed to assess whether the observed findings will transform into sustained long-term clinical benefit.

Enoxaparin dose impacts blood cell phenotypes during mild SARS-CoV-2 infection: the observational single-center study.

Coronavirus disease 2019 (COVID-19) is associated with various hemostatic abnormalities requiring constant search for better delicate antithrombotic management in these high-risk patients. The choice and the optimal dose of anticoagulant is important, but unclear, especially for mild COVID-19. Enoxaparin has been tested in several COVID trials with mixed results regarding hard clinical outcomes including mortality. We analyzed clinical, laboratory data and changes in platelets, erythrocytes and leukocytes by scanning electron microscopy on admission and at hospital discharge in patients with confirmed COVID-19 treated with enoxaparin (n = 31) and matched healthy controls (n = 32) in a retrospective observational study. The data were triaged by enoxaparin dose comparing 40 mg/daily prophylactic enoxaparin dose (PED) with 80 mg/daily therapeutic (TED) regimens. All patients experienced mild disease, none required pulmonary support, and all survived. The impact of enoxaparin dose was prominent for platelets and erythrocytes, but less evident for leukocytes. PED was associated with significant platelet activation, diminished numbers of silent nonactive discoid cells, and increased number and size of platelet microaggregates with leukocyte involvement. In contrast, TED did not cause extra platelet activation, while circulating platelet microaggregates were smaller and lacking leukocytes in their construction. PED caused significant increase of erythrocyte-platelet aggregates formation, and numerically higher proportion of circulating echinocytes. TED was associated with significant decrease of rouleaux sludge formation compared to only some trend after PED. Changes in leukocytes were less dependent on enoxaparin dose. However, PED has been associated with enhanced aggregate formation in 7 out of 10 patients, while trap net formation has been decreased in 17 out of 21 TED patients. We conclude that over hospital stay TED was superior to PED in patients with mild COVID-19. The inability of PED to adequately protect major circulating blood cells is probably due to enhanced clearance or/and diminished bioavailability of enoxaparin during COVID. These retrospective observational small sample size data may be relevant to better understanding of the mixed results in controlled outcome-driven trials exploring optimal COVID-19 anticoagulant strategies.

The efficacy and safety of levilimab in severely ill COVID-19 patients not requiring mechanical ventilation: results of a multicenter randomized double-blind placebo-controlled phase III CORONA clinical study.

OBJECTIVE AND DESIGN: The aim of this double-blind, placebo-controlled, phase III CORONA clinical trial was to evaluate the efficacy and safety of IL-6 receptor inhibitor levilimab (LVL) in subjects with severe COVID-19. SUBJECTS: The study included 217 patients. The eligible were men and non-pregnant women aged 18 years or older, hospitalized for severe COVID-19 pneumonia. TREATMENT: 206 subjects were randomized (1:1) to receive single subcutaneous administration of LVL 324 mg or placebo, both in combination with standard of care (SOC). 204 patients received allocated therapy. After the LVL/placebo administration in case of deterioration of symptoms, the investigator could perform a single open-label LVL 324 mg administration as the rescue therapy. METHODS: The primary efficacy endpoint was the proportion of patients with sustained clinical improvement on the 7-category ordinal scale on Day 14. All efficacy data obtained after rescue therapy administration were considered missing. For primary efficacy analysis, all subjects with missing data were considered non-responders. RESULTS: 63.1% and 42.7% of patients in the LVL and in the placebo groups, respectively, achieved sustained clinical improvement on Day 14 (P = .0017). The frequency of adverse drug reactions was comparable between the groups. CONCLUSION: In patients with radiologically confirmed SARS-CoV-2 pneumonia, requiring or not oxygen therapy (but not ventilation) with no signs of other active infection administration of LVL + SOC results in an increase of sustained clinical improvement rate. TRAIL REGISTRATION: The trial is registered at the US National Institutes of Health (ClinicalTrials.gov; NCT04397562).

Impact of olokizumab on platelets, leukocytes and erythrocytes during mild COVID-19.

No abstract present.

Mild COVID-19 and Impaired Blood Cell-Endothelial Crosstalk: Considering Long-Term Use of Antithrombotics?

BACKGROUND: Current coronavirus disease 2019 (COVID-19) pandemic reveals thrombotic, vascular, and endothelial dysfunctions at peak disease. However, the duration, degree of damage, and appropriate long-term use of antithrombotic strategies are unclear. Most COVID data are yielded from random clinical observations or autopsy of postmortem samples, while precise blood cellular data in survivors are insufficient. METHODS: We analyzed erythrocytes, circulating endothelial cells, and echinocytes by electron microscopy and flow cytometry in patients with confirmed COVID-19 (n = 31) and matched healthy controls (n = 32) on admission and at hospital discharge. RESULTS: All patients experienced mild disease, none required pulmonary support, and all survived. Admission number of circulating endothelial cells was significantly (40-100 times) higher in COVID-19 patients. Cells were massively damaged by multiple fenestrae in membranes with diameter comparable to the size of supercapsid in SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) virus. COVID-19 also provoked formation of stacked aggregated erythrocytes capable of clogging microvascular bed and of diminishing oxygen supply. In some patients, such abnormalities persisted at hospital discharge revealing remaining intracellular penetration of SARS-CoV-2 where it may be replicated and returned to circulation. CONCLUSION: These observational and descriptive data suggest that persistent viral cell injury may cause blood vessel damage; their increased permeability resulted in tissue edema, inflammation, platelet activation, and augmented thrombosis. There is a residual blood cell damage following the acute phase in some COVID-19 survivors. Controlled outcome-driven trials are urgently needed for exploring optimal use of long-term antithrombotics and vascular protection strategies even after mild COVID-19.

AVIFAVIR for Treatment of Patients With Moderate Coronavirus Disease 2019 (COVID-19): Interim Results of a Phase II/III Multicenter Randomized Clinical Trial.

In May 2020 the Russian Ministry of Health granted fast-track marketing authorization to RNA polymerase inhibitor AVIFAVIR (favipiravir) for the treatment of COVID-19 patients. In the pilot stage of Phase II/III clinical trial, AVIFAVIR enabled SARS-CoV-2 viral clearance in 62.5% of patients within 4 days, and was safe and well-tolerated. Clinical Trials Registration. NCT04434248.