The acute respiratory illnesses caused by severe acquired respiratory syndrome corona Virus-2 (SARS-CoV-2) is a global health emergency, involving more than 8.6 million people worldwide with more ...than 450,000 deaths. Among the clinical manifestations of COVID-19, the disease that results from SARS-CoV-2 infection in humans, a prominent feature is a pro-thrombotic derangement of the hemostatic system, possibly representing a peculiar clinicopathologic manifestation of viral sepsis. The severity of the derangement of coagulation parameters in COVID-19 patients has been associated with a poor prognosis, and the use of low molecular weight heparin (LMWH) at doses registered for prevention of venous thromboembolism (VTE) has been endorsed by the World Health Organization and by Several Scientific societies. However, some relevant issues on the relationships between COVID-19, coagulopathy and VTE have yet to be fully elucidated. This review is particularly focused on four clinical questions: What is the incidence of VTE in COVID-19 patients? How do we frame the COVID-19 associated coagulopathy? Which role, if any, do antiphospolipid antibodies have? How do we tackle COVID-19 coagulopathy? In the complex scenario of an overwhelming pandemic, most everyday clinical decisions have to be taken without delay, although not yet supported by a sound scientific evidence. This review discusses the most recent findings of basic and clinical research about the COVID-associated coagulopathy, to foster a more thorough knowledge of the mechanisms underlying this compelling disease.
To assess whether high doses of Low Molecular Weight Heparin (LMWH) (i.e. Enoxaparin 70 IU/kg twice daily) compared to standard prophylactic dose (i.e., Enoxaparin 4000 IU once day), in hospitalized ...patients with COVID19 not requiring Invasive Mechanical Ventilation IMV, are: a)more effective in preventing clinical worsening, defined as the occurrence of at least one of the following events, whichever comes first: 1.Death2.Acute Myocardial Infarction AMI3.Objectively confirmed, symptomatic arterial or venous thromboembolism TE4.Need of either: a.Continuous Positive Airway Pressure (Cpap) or Non-Invasive Ventilation (NIV) orb.IMV in patients who at randomisation were receiving standard oxygen therapy5.IMV in patients who at randomisation were receiving non-invasive mechanical ventilationb)Similar in terms of major bleeding risk TRIAL DESIGN: Multicentre, randomised controlled, superiority, open label, parallel group, two arms (1:1 ratio), in-hospital study.
Inpatients will be recruited from 7 Italian Academic and non-Academic Internal Medicine Units, 2 Infectious Disease Units and 1 Respiratory Disease Unit.
1. Age > 18 and < 80 years 2. Positive SARS-CoV-2 diagnostic (on pharyngeal swab of deep airways material) 3. Severe pneumonia defined by the presence of at least one of the following criteria: a.Respiratory Rate ≥25 breaths /minb.Arterial oxygen saturation≤93% at rest on ambient airc.PaO2/FiO2 ≤300 mmHg 4. Coagulopathy, defined by the presence of at least one of the following criteria: a.D-dimer >4 times the upper level of normal reference rangeb.Sepsis-Induced Coagulopathy (SIC) score >4 5. No need of IMV EXCLUSION CRITERIA: 1. Age <18 and >80 years 2. IMV 3. Thrombocytopenia (platelet count < 80.000 mm3) 4. Coagulopathy: INR >1.5, aPTT ratio > 1.4 5. Impaired renal function (eGFR calculated by CKD-EPI Creatinine equation < 30 ml/min) 6. Known hypersensitivity to enoxaparin 7. History of heparin induced thrombocytopenia 8. Presence of an active bleeding or a pathology susceptible of bleeding in presence of anticoagulation (e.g. recent haemorrhagic stroke, peptic ulcer, malignant cancer at high risk of haemorrhage, recent neurosurgery or ophthalmic surgery, vascular aneurysms, arteriovenous malformations) 9. Concomitant anticoagulant treatment for other indications (e.g. atrial fibrillation, venous thromboembolism, prosthetic heart valves) 10. Concomitant double antiplatelet therapy 11. Administration of therapeutic doses of LMWH, fondaparinux, or unfractionated heparin (UFH) for more than 72 hours before randomization; prophylactic doses are allowed 12. Pregnancy or breastfeeding or positive pregnancy test 13. Presence of other severe diseases impairing life expectancy (e.g. patients are not expected to survive 28 days given their pre-existing medical condition) 14. Lack or withdrawal of informed consent INTERVENTION AND COMPARATOR: Control Group (Low-Dose LMWH): patients in this group will be administered Enoxaparin (Inhixa®) at standard prophylactic dose (i.e., 4000 UI subcutaneously once day). Intervention Group (High-Dose LMWH): patients in this group will be administered Enoxaparin (Inhixa®) at dose of 70 IU/kg every 12 hours, as reported in the following table. This dose is commonly used in Italy when a bridging strategy is required for the management of surgery or invasive procedures in patients taking anti-vitamin K oral anticoagulants Body Weight (kg)Enoxaparin dose every 12 hours (IU)<50200050-69400070-89600090-1108000>11010000 The treatment with Enoxaparin will be initiated soon after randomization (maximum allowed starting time 12h after randomization). The treatment will be administered every 12 hours in the intervention group and every 24 hours in the control group. Treatments will be administered in the two arms until hospital discharge or the primary outcomes detailed below occur.
Primary Efficacy Endpoint: Clinical worsening, defined as the occurrence of at least one of the following events, whichever comes first: 1.Death2.Acute Myocardial Infarction AMI3.Objectively confirmed, symptomatic arterial or venous thromboembolism TE4.Need of either: a.Continuous Positive Airway Pressure (Cpap) or Non-Invasive Ventilation (NIV) orb.IMV in patients who at randomisation were in standard oxygen therapy by delivery interfaces5.Need for IMV, in patients who at randomisation were in Cpap or NIV Time to the occurrence of each of these events will be recorded. Clinical worsening will be analysed as a binary outcome as well as a time-to-event one. Secondary Efficacy Endpoints: Any of the following events occurring within the hospital stay 1.Death2.Acute Myocardial Infarction AMI3.Objectively confirmed, symptomatic arterial or venous thromboembolism TE4.Need of either: a.Continuous Positive Airway Pressure (Cpap) or Non-Invasive Ventilation (NIV) orb.IMV in patients who at randomisation were in standard oxygen therapy by delivery interfaces5.Need for IMV in patients who at randomisation were in Cpap or NIV6.Improvement of laboratory parameters of disease severity, including: o D-dimer levelo Plasma fibrinogen levelso Mean Platelet Volumeo Lymphocyte/Neutrophil ratioo IL-6 plasma levels MORTALITY AT 30 DAYS: Information about patients' status will be sought in those who are discharged before 30 days on Day 30 from randomisation. Time to the occurrence of each of these events will be recorded. Each of these events will be analysed as a binary outcome and as a time-to-event one. Primary safety endpoint: Major bleeding, defined as an acute clinically overt bleeding associated with one or more of the following: Decrease in haemoglobin of 2 g/dl or more;Transfusion of 2 or more units of packed red blood cells;Bleeding that occurs in at least one of the following critical sites intracranial, intraspinal, intraocular (within the corpus of the eye; thus, a conjunctival bleed is not an intraocular bleed), pericardial, intra-articular, intramuscular with compartment syndrome, or retroperitoneal;Bleeding that is fatal (defined as a bleeding event that was the primary cause of death or contributed directly to death);Bleeding that necessitates surgical intervention Time to the occurrence of each of these events will be recorded. Each of these events will be analysed as a binary outcome and as a time-to-event one. Secondary safety endpoint: Clinically Relevant non-major bleeding, defined as an acute clinically overt bleeding that does not meet the criteria for major and consists of: 1.Any bleeding compromising hemodynamic2.Spontaneous hematoma larger than 25 cm2, or 100 cm2 if there was a traumatic cause3.Intramuscular hematoma documented by ultrasonography4.Epistaxis or gingival bleeding requiring tamponade or other medical intervention5.Bleeding from venipuncture for >5 minutes6.Haematuria that was macroscopic and was spontaneous or lasted for more than 24 hours after invasive procedures7.Haemoptysis, hematemesis or spontaneous rectal bleeding requiring endoscopy or other medical intervention8.Any other bleeding requiring temporary cessation of a study drug. Time to the occurrence of each of these events will be recorded. Each of these events will be analysed as a binary outcome and as a time-to-event one.
Randomisation (with a 1:1 randomisation ratio) will be centrally performed by using a secure, web-based system, which will be developed by the Methodological and Statistical Unit at the Azienda Ospedaliero-Universitaria of Modena. Randomisation stratified by 4 factors: 1) Gender (M/F); 2) Age (<75/≥75 years); 3) BMI (<30/≥30); 4) Comorbidities (0-1/>2) with random variable block sizes will be generated by STATA software. The web-based system will guarantee the allocation concealment. Blinding (masking) The study is conceived as open-label: patients and all health-care personnel involved in the study will be aware of the assigned group.
The target sample size is based on the hypothesis that LMWH administered at high doses versus low doses will significantly reduce the risk of clinical worsening. The overall sample size in this study is expected to be 300 with 150 in the Low-Dose LMWH control group and 150 in the High-Dose LMWH intervention group, recruited over 10-11 months. Assuming an alpha of 5% (two tailed) and a percentage of patients who experience clinical worsening in the control group being between 25% and 30%, the study will have 80% power to detect at least 50% relative reduction in the risk of death between low and high doses of heparin.
Protocol version 1.2 of 11/05/2020. Recruitment start (expected): 08/06/2020 Recruitment finish (expected): 30/04/2021 Trial registration EudraCT 2020-001972-13, registered on April 17th, 2020 Full protocol The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.
: Extended half-life (EHL) factor IX (FIX) concentrates allow for prophylaxis with prolonged dosing intervals and high bleeding protection in persons with hemophilia B. Long-term real-world studies ...are lacking.
: In a retrospective-prospective study, the six-year use of prophylaxis with the EHL recombinant FIX-albumin fusion protein (rIX-FP) was analyzed, comparing outcomes with previous standard half-life (SHL) FIX in patients already on prophylaxis.
: Prophylaxis with rIX-FP was prescribed in 15 patients (10 severe, 5 moderate; follow-up: 57 ± 17 months). Based on a pharmacokinetic assessment and clinical needs, the first regimen was 47 ± 7 IU/Kg every 9 ± 2 days. All but one patient remained on rIX-FP prophylaxis, adjusting infusion frequency and/or dose; the last prescribed frequency was ≥10 days in 10/13 patients, being reduced in seven and increased in four vs. the first regimen. The weekly FIX dose was unchanged; FIX trough levels were >5% in all patients. The annual infusion number and FIX IU/Kg significantly decreased (~60%) in eight patients previously on SHL FIX prophylaxis, with similar concentrate costs. Very low bleeding rates (most traumatic bleeds and the last quartile of the infusion interval), improved orthopedic and pain scores, unchanged HEAD-US scores and problem joints, and high treatment adherence (>90%) and satisfaction were registered.
: Personalized, carefully adjusted rIX-FP regimens contribute to the diffusion and optimization of prophylaxis in persons with severe and moderate hemophilia B, with long-term favorable bleeding, joint, and patient-reported outcomes.
This is a retrospective, record-linkage study aimed at comparing the effectiveness and safety of two management models of vitamin K antagonists: a Network model (NAS), in which anticoagulation ...clinics and general practitioners (GP) share the same management software and database, and an individual General Practitioners model. Main outcomes were thromboembolic events (TE), major bleeding (MB) and all-cause mortality. Crude incidence rate and sub-distribution hazard ratio were calculated. Fine and Grey models were used to calculate SHR in multi-variable analysis. 9,418 patients in the NAS and 5,508 in the Routine General Care (RGC) cohort were included. Patients in the NAS cohort had a lower incidence of TE and mortality in respect to the RGC (sHR 0.76%, 95% CI 0.64-0.90 and 0.82%, 95% CI 0.75-0.89, respectively). More patients in the NAS than in the RGC cohort attained a Time in Therapeutic Range >60% (62.2% vs 35.7%, p<0.001). No statistically significant difference was found in MB incidence. This study shows that the NAS model for vitamin K antagonist oral anticoagulants management significantly improves the TTR and reduces the incidence of TE and mortality, without affecting the MB rate.
Chronic lymphocytic leukemia B cells display prolonged survival in vivo, but when cultured in vitro rapidly undergo spontaneous apoptosis. We hypothesize that interactions with endothelial cells in ...infiltrated tissues and during recirculation may have a pathogenic role in chronic lymphocytic leukemia.
We evaluated apoptosis of leukemic cells after co-culture on a monolayer of human umbilical vein endothelial cells with addition of fludarabine and antibodies that block adhesion. Then, we compared microarray-based gene expression profiles between leukemic cells at baseline and after co-culture.
We found that the endothelial layer protected leukemic cells from apoptosis inducing a 2-fold mean decrement in apoptotic cells after 2 days of co-culture. Moreover, the endothelial layer decreased the sensitivity of chronic lymphocytic leukemia B cells to fludarabine-induced apoptosis. Physical contact with endothelium mediated by both β(1)- and β(2)- integrins is essential for the survival advantage of leukemic cells. In particular, blocking CD106 on endothelial cells or CD18 on leukemic B cells led to the almost complete abrogation of the survival advantage (>70% inhibition of viability). However, a reduction of apoptosis was also measured in leukemic cells cultured in conditioned medium collected after 2 days of co-culture, implying that survival is partially mediated by soluble factors. Overall, the contact with endothelial cells modulated 1,944 genes in chronic lymphocytic leukemia B cells, establishing a peculiar gene expression profile: up-regulation of angiogenesis-related genes, an increase of genes involved in TGFβ and Wnt signaling pathways, secretion of cytokines recruiting stromal cells and macrophages and up-regulation of anti-apoptotic molecules such as Bcl2 and Survivin.
Our study supports the notion that endothelial cells are major players in the chronic lymphocytic leukemia microenvironment. Adhesion to endothelium strongly supports survival, protects from drug-induced apoptosis and extensively modifies the gene expression profile of leukemic cells.
The clinical relevance of angiopoietin-2 (Ang2) in chronic lymphocytic leukemia (CLL) was previously suggested by the association between high Ang2, and shorter progression-free survival reported in ...small series of patients. Here, we evaluated Ang2 glycoprotein levels in plasma samples collected from a multicentric cohort of CLL patients (n = 316) using an enzyme-linked immunosorbent assay method, and we investigated its prognostic role in relation to time to first treatment (TTFT) and overall survival. Based on a cutoff equal to 2459 pg/mL, we divided our cohort in 2 subsets (high and low Ang2) composing 100 (31.6%) and 216 (68.4%) patients, respectively. High Ang2 was predictive of reduced TTFT (P < .001) and overall survival (P = .002). Multivariate analysis confirmed that high Ang2 was an independent prognosticator for TTFT (hazard ratio = 1.739; 95% confidence interval, 1.059-2.857; P = .029). Significant associations were found between high Ang2 and advanced Binet stages (P < .001), high β2-microglobulin (P < .001), unmutated variable region of immunoglobulin heavy chain gene status (P < .001), high CD38 and ζ-chain-associated protein kinase 70 expression (P < .001 and P = .003), and intermediate/high cytogenetic risk (P = .005). Moreover, Ang2 added prognostic power to other conventional prognosticators and helped to refine prognosis among CLL subsets with both high and low vascular endothelial growth factor plasma levels. Ang2 plasma level may be a useful independent prognosticator for CLL.
•VITT is a rare complication observed in recipients of AdV-based COVID-19 vaccines.•VITT is defined by anti-PF4 antibodies, thrombocytopenia and arterial and venous thrombosis.•Anti-PF4 antibodies ...seem to be elicited by negatively charged proteins from AdV vectors.•A proinflammatory milieu induced by vaccine components can foster the anti-PF4 immune response.•Acquired or inherited factors, not jet fully defined, can predispose individuals to develop VITT.
Vaccine-induced immune thrombocytopenia and thrombosis (VITT) is a rare syndrome characterized by high-titer anti-platelet factor 4 (PF4) antibodies, thrombocytopenia and arterial and venous thrombosis in unusual sites, as cerebral venous sinuses and splanchnic veins.
VITT has been described to occur almost exclusively after administration of ChAdOx1 nCoV-19 and Ad26.COV2.S adenovirus vector- based COVID-19 vaccines.
Clinical and laboratory features of VITT resemble those of heparin-induced thrombocytopenia (HIT). It has been hypothesized that negatively charged polyadenylated hexone proteins of the AdV vectors could act as heparin to induce the conformational changes of PF4 molecule that lead to the formation of anti-PF4/polyanion antibodies. The anti-PF4 immune response in VITT is fostered by the presence of a proinflammatory milieu, elicited by some impurities found in ChAdOx1 nCoV-19 vaccine, as well as by soluble spike protein resulting from alternative splice events.
Anti-PF4 antibodies bind PF4, forming immune complexes which activate platelets, monocytes and granulocytes, resulting in the VITT's immunothrombosis.
The reason why only a tiny minority of patents receiving AdV-based COVID-19 vaccines develop VITT is still unknown. It has been hypothesized that individual intrinsic factors, either acquired (i.e., pre-priming of B cells to produce anti-PF4 antibodies by previous contacts with bacteria or viruses) or inherited (i.e., differences in platelet T-cell ubiquitin ligand-2 TULA-2 expression) can predispose a few subjects to develop VITT.
A better knowledge of the mechanistic basis of VITT is essential to improve the safety and the effectiveness of future vaccines and gene therapies using adenovirus vectors.
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