Phospholipid-dependent Clotting Time Research Articles

Cold vs. Room Temperature: A Comparative Analysis of Platelet Functionality in Cold Storage

Background: The platelet functionality of cold-stored platelets remains a subject of debate. Our aim was to investigate the effect of temperature on the hemostatic properties of stored platelets. Methods: Ten split pooled platelets stored at cold and at room temperature were evaluated in vitro on storage days 1, 5, 10, and 15 for metabolic, physiological, and vesiculation parameters, as well as their hemostatic profile using rotational thromboelastometry (ROTEM®). Results: The integrity profile was better preserved in the cold-stored platelets, as lower lactate dehydrogenase levels were documented (e.g., day 10: 261 ± 46 vs. 572 ± 220 U/L, 4 vs. 22 °C, p = 0.004). A time-dependent decrease in hemostatic capacity was evident regardless of the temperature, but the cold-stored units were linked to shorter clot initiation times and increased elasticity, strength, and firmness parameters, especially during extended storage (e.g., maximum clot firmness, INTEM day 15: 81 ± 2 vs. 19 ± 4 mm, 4 vs. 22 °C, p = 0.0008). Additionally, the aggregation of cold-stored platelets was superior after the addition of any agonist tested. Regarding vesiculation parameters, the extracellular vesicles of the units at 4 °C were characterized by a larger size from day 10 onwards, when they also presented higher procoagulant activity (e.g., phospholipid-dependent clotting time of day 15: 21.4 ± 2.3 vs. 25.0 ± 3.0 s, 4 vs. 22 °C, p = 0.016). Conclusion: Our results indicate that cold-stored platelets perform better than those stored at room temperature, demonstrating superior clot formation and stability. This suggests that cold storage may more effectively preserve platelet function, potentially offering advantages for transfusion therapy and the extension of shelf-life. However, the clinical relevance of these findings requires further investigation.

Profiling plasma alterations of extracellular vesicles in patients with acutely decompensated cirrhosis and bacterial infection.

Extracellular vesicles (EVs) modulate inflammation, coagulation and vascular homeostasis in decompensated cirrhosis. To characterize the profile of plasmatic EVs in patients with decompensated cirrhosis and bacterial infections and evaluate the association between EVs and the development of hemostatic complications. We measured the levels of EVs using high-sensitivity flow cytometry and phospholipid-dependent clotting time (PPL) in a prospective cohort of hospitalized patients with acutely decompensated cirrhosis with versus without bacterial infections. A separate cohort of patients with bacterial infections without cirrhosis was also enrolled. We measured endothelium-, tissue factor (TF)-bearing, platelet- and leukocyte-derived EVs. In patients with infections, EVs were reassessed upon resolution of infection. Bleeding and thrombotic complications were recorded during 1-year follow-up. Eighty patients with decompensated cirrhosis were recruited (40 each with and without bacterial infections). Electron microscopy confirmed the presence of plasma EVs. Despite no difference in total EVs and PPL, patients with cirrhosis and infection had significantly higher TF+ EVs, P-Selectin+ EVs (activated platelet-derived), CD14+ EVs (monocyte/macrophages derived) and CD14+ TF+ EVs versus those with cirrhosis without infection. Upon infection resolution, levels of these EVs returned to those without infection. Patients with infections showed a significant association between reduced P-Selectin+ EVs and bleeding complications (HR 8.0 [95%CI 1.3-48.1]), whereas high levels of leukocyte-derived EVs (CD45+) and CD14+ EVs were significantly associated with thrombotic complications (HR 16.4 [95%CI 1.7-160] and 10.9 [95%CI 1.13-106], respectively). Results were confirmed in a validation cohort. Bacterial infections are associated with particular alterations of plasma EVs profile in decompensated cirrhosis. Bacterial infections trigger the release of EVs originating from various cell types, which may tip the precarious hemostatic balance of patients with acutely decompensated cirrhosis towards hyper- or hypocoagulability.

Leukemia Inhibitory Factor, Tissue Factor, Thrombomodulin, P-Selectine, D-Dimer, Thrombin Generation and Procoagulant Phospholipid Dependent Clotting Time Are Predictive for in Vitro Fertilization Outcome. the Prospective Roadmap-IVF Study

Background The link between blood hypercoagulability, endothelial cell activation and infertility or in vitro fertilization (IVF) failure is a puzzling issue. Activation of platelets, endothelial cells and blood coagulation, proinflammatory and angiogenetic potential play important role in implantation and early embryonic development. Biomarkers of cellular hypercoagulability are associated with high risk of IVF failure. Soluble Leukemia Inhibitory Factor (LIF), an interleukin 6 class cytokine expressed in the trophectoderm of the developing embryo is an important regulator in the establishment of pregnancy. Endoglin (Eng), a co-receptor for TGF-β1 and TGF-β3 is implicated in vascular complications of pregnancy and particularly in preeclampsia. Aim: The prospective longitudinal monocentric observational cohort study ROADMAP-IVF, evaluated the synergistic prognostic value of LIF and Eng with the biomarkers of cellular hypercoagulability in predicting the endometrial receptivity of fresh IVF cycles. Materials and Methods. The ROADMAP-IVF enrolled 40 women eligible for IVF with normal blood count, PT, aPTT, Fg, renal and liver function. The control group (CG) consisted of 30 healthy women with history of uncomplicated pregnancies. Exclusion criteria: Use of anticoagulant or antiplatelet agents during the last 30 days before inclusion. Known cardiovascular disease, active cancer. Active corticosteroid treatment. Primary end-point: Echographically documented pregnancy at 7 weeks from implantation. Blood was collected on day 2 (D2) from the natural cycle and 6 days after hormone treatment initiation corresponding to D8 of the cycle. Procoagulant phospholipid-dependent clotting time (PPL-ct), tissue factor (TF), thrombomodulin (TM), von Willebrand factor (vWF) and D-Dimers (DDi) were measured with assays from Diagnostica Stago (Asnieres, France). P- and E-Selectin, LIF and Eng were measured with ELISA. Thrombin generation (TG) with the TF 5 pM PPP-Reagent ® was assessed on Calibrated Automated Thrombogram (Stago, France). The cut-off values for studied biomarkers have been selected on the basis of ROC analysis. Univariate and multivariate logistic regression analysis examined the associations between the biomarkers and the study outcome. Results: 40 women were enrolled in the study. In 11 women pregnancy was confirmed with ultrasound and in 23 women no pregnancy was echographically documented. Age was not significantly different between the IVF (41 ys; range 22 - 48 ys) and the control group (40 ys; range 20 - 46 ys). At D2 and D8 the DDi and LIF were significantly higher in IVFG as compared to the CG. At D2 most of the patients had PPL-ct, DDi and MRI of TG higher than the upper normal limit (UNL). At D8 only TF was significantly increased as compared to the CG. Analytical data are presented in Table 1. Age did not correlate with the levels of the studied biomarkers. Significant correlations (p<0.05) were found between DDi and ETP (r=0.35); TM, TF and P-Selectin (r=0.4) at D2; TF, LIF and Eng (r=0.5) at D2 and D8; P-Selectin and PPL-ct (r=-0.4) at D2; P-Selectin and TM (r=0.4), E-Selectin (r=0.5), LIF (0.4) at D2; E-Selectin and P-Selectin (r=0.5), TF (r=0.3), and LIF (r=0.4) at D2. The ROC analysis showed that IVF failure was associate with DDi increase at D2 (AUC = 0.64); P-Selectin increase at D2(AUC = 0.57) and D8 (AUC = 0.61); TM increase at D8 (AUC = 0.61); TF increase at D8 (AUC = 0.57); LIF increase at D8 (AUC = 0.59); ETP increase at D2 (AUC = 0.67) and D8 (AUC = 0.67); Peak increase at D2 (AUC = 0.64) and D8 (AUC = 0.61). Prolongation of PPL-ct on D8 was predictive for positive pregnancy outcome(AUC 0.64). Conclusion The ROADMAP-IVF study showed that at least one out of four women eligible for IVF present biological evidence of activation of platelets, endothelial cells, blood coagulation or LIF upregulation. Hormone treatment administration does not significantly alter the proinflammatory or the hypercoagulable state. Among the studied biomarkers the levels of LIF, DDi, P-Selectine, TM and TF as well as the status of thrombin generation and PPL-ct showed a significant predictive value for the IVF outcome, particularly when measured at 6 days after hormone treatment administration. These findings will lead to the elaboration of an risk assessment model for IVF failure combining the selected biomarkers of hypercoagulability with LIF.

The Procoagulant Phospholipid Dependent Clotting Time and the Initiation Phase of Thrombin Generation Test Are Mandatory for the Evaluation of the Risk for Severe Early Onset Preeclampsia

Bakground: Preeclampsia occurs in up to 7% of pregnancies in Western Countries and is a leading cause of maternal and fetal morbidity and mortality. Classification of preeclampsia is based on the timing of symptoms' onset and the severity of the clinical status. Accordingly, early and late preeclampsia are characterized by symptom onset before or after 32-34 weeks of gestation respectively. Pathogenesis of preeclampsia is characterized by abnormal placental vascular development with impaired invasion of the uterine spiral arteries by trophoblasts, resulting in fetal complications and maternal endothelial dysfunction. Intact antithrombotic properties of the endothelial cells and efficient regulation of thrombin generation and platelet activation at the microenvironment of the uterus are necessary conditions for successful trophoblast invasion and development of feto-maternal circulation during normal pregnancy. , Prompt identification of pregnant women at risk of preeclampsia worsening could help to anticipated therapeutic intervention and improvement of the clinical outcome. Aim: The ROADMAP-Early Onset Preeclampsia study (ROADMAP-EOP) aiming to respond to this unmet need assessed the clinical relevance of biomarkers of hypercoagulability and endothelial activation for prompt identification of pregnant women at high risk of preeclampsia. Materials and Methods: An observational single center retrospective case-control study was conducted in pregnant women diagnosed with preeclampsia from July 2020 to July 2021. Pregnant women were retrospectively enrolled upon EOP diagnosis and stratified in mild EOP group (n=34) and severe EOP group (n=15 according to the criteria of the International Society for the Study of Hypertension in Pregnancy ). Eligible women were included in the study before initiation of any treatment for preeclampsia. The control group (n=35) consisted of women with uncomplicated pregnancy. All women were assessed with thromboelastometry, Calibrated Automated Thrombo-gram®, tissue factor activity (TFa), Procoagulant phospholipid dependent clotting time (Procoag-PPL), Proteins S, TFPI, D-dimer, antithrombin, thrombomodulin, fibrinogen prothrombin time and activated partial thromboplastin time. Primary and secondary end points were severe EOP and EOP respectively. Principal component analysis (PCA) was performed to check for associations among the biomarkers and the clinical out-come. Results: There were no significant differences regarding age, gravidity, gestational age and the body mass index (BMI) between EOP groups and normal pregnancy as well as within the EOP groups. Platelet counts were similar in healthy pregnant women, and mild EOP group, and significantly lower in severe EOP (p<0.05). No other statistically significant differences were found between-groups. The PCA showed that the repartition of data allowed to discriminate the patients with EOP from healthy pregnant women as well as patients with mild EPO from those with severe EOP. When biomarkers of hypercoagulability were considered according to the severity of EOP in PCA analysis the lag-time and PPL clotting time were independently associated with the risk of severe EOP (Table 1and Figure 1)). The increase of the lag-time by 1 min was associated with a 20.2-fold increase of the risk of severe EOP. The marginal effects curve shows that for a lag-time longer than 2.6 min, the probability of severe EOP was higher than 50% .Longer Procoag-PPL clotting time was associated with lower risk of severe EOP. The marginal effects curve, showed that for Procoag-PPL clotting time longer than 58.75 sec the probability of severe EOP decreased by 50%. These data suggest that a biological score composed of the Procoag-PPL® clotting time and thrombin generation (Throbmogram-Thrombinoscope® PPP-reagent 1 pM-TF as-say) could be a useful tool to identify pregnant women with high probability of EOP Conclusion: the Procoag-PPL® clotting time and thrombin generation assay reflect cellular derived hypercoagulability and allow accurate screening of pregnant women for the prompt identification of those at risk of EOP and the evaluation of its severity. This concept has to be validated in a large prospective cohort trial. . An external validation of the proposed methodology needs to be performed in a large prospective observational study.

Persisting Endothelial Cell Activation and Hypercoagulability after Recovering from COVID-19: The Roadmap-Post COVID-19 Study

Background: In patients with severe COVID-19, activation of blood coagulation and endothelial cells orchestrated with complement activation and cytokine storm leads to disease worsening and death. Hypercoagulable state and endothelial cell activation and fibrinolytic unbalance are common alterations in patients with COVID-19 hospitalized either at the conventional medical ward or at the intensive care unit (ICU). Two systematic reviews highlight that D-dimer values are higher in non survivors as well as in patients with severe COVID-19 than in those with mild disease, showing the association between D-dimer levels and disease severity or death. Nevertheless, there are limited data in small series of patient, on the persistence of hypercoagulability and endothelial cell activation following recovery from COVID-19. Aims: To investigate the persistence of endothelial cell activation and hypercoagulability after recovery from COVID-19. Patients/Methods. COVID-19 survivors (n = 208) and 30 healthy individuals were enrolled in this study. Methods: In ,total, 208 COVID-19 survivors were included in the study; 125 males (60%) and 83 females (40%) with a median age of 50 years (IQR = 20, range 18 to 78 years). Biomarkers of hypercoagulability and endothelial cell activation: The procoagulant phospholipid-dependent clotting time (PPL-ct) was measured using a factor Xa-based clotting assay STA®-Procoag-PPL. Free-TFPI levels were measured with the ELISA Free TFPI, Asserachrom®; D-dimer and fibrin monomers (FM) were measured by STA Liatest D-Di and STA Liatest FM; soluble thrombomodulin (sTM) was measured by Asserachrom® TM. All assays were from Diagnostica Stago, Asnières, France. Heparanase-levels were measured with ELISA kits R&D. Systems (Lille France). Detection of anti-SARS-CoV2 antibodies: IgG and IgA anti-SARS-CoV-2 antibodies were detected in the sera of the survivors using a semi-quantitative commercial ELISA methodology (Euroimmun Medizinische Labordiagnostika AG, Lubeck, Germany) Results: The median interval between symptom onset and screening for SARS-CoV-2 antibodies was 62 days (IQR = 22 days). Antibodies against SARS-CoV-2 were detected in all survivors enrolled in the study. The median level of IgG and IgA antibodies was 5.68 U (IQR = 6.19) and 3.62 U (IQR = 5.36), respectively. In 112 survivors with known blood group, 48 (43%) were group O, 44 (39%) were group A, 14 (13%) were group B, and 6 (5.4%) were group AB. Survivors showed significantly higher levels of D-Dimers, FM, TFPI, and heparanase as compared to that of the control group. Survivors had significantly shorter PPL-ct . One out of four of COVID-19 survivors showed increase at least one biomarker of endothelial cell activation or hypercoagulability (Table1). Elevated D-dimer was associated with older age. Elevated FM was associated with female gender. Elevated heparanase was independently associated with male gender. Decreased Procoag-PPL clotting time was associated with female gender. Univariate and multivariate logistic regression analysis examining predictors of hypercoagulability in study cohort of COVID-19 survivors are reported in table 2 . The interval between COVID-19 diagnosis and assessment was not associated with the changes of the studied biomarkers. Conclusion: The ROADMAP-postCOVID-19 study offers an analysis of a large panel of biomarkers of endothelial cell activation and hypercoagulability in survivors of COVID-19. The study documents that two months after symptoms' onset, activation of endothelial cells, in vivo thrombin generation, and fibrin lysis are frequent phenomena up to two months from COVID-19 symptom onset. The data presented herein allow to propose that evaluation of blood hypercoagulability (using D-dimer for instance) and endothelial cell activation could offer the possibility of prompt identification of COVID-19 survivors at risk of post-COVID-19 vascular complications. The findings of the present study underline the need for a thorough evaluation of a potential correlation between the sustained hypercoagulability and endothelial cell activation with the symptomatology of long-COVID-19 to apply anticipated diagnostic and therapeutic strategies. The clinical relevance of the identified biomarkers of endothelial activation and hypercoagulability in the assessment of the risk of long COVID-19 must be investigated in a prospective study. Figure 1View largeDownload PPTFigure 1View largeDownload PPT Close modal

The COMPASS-COVID-19-ICU Study: Identification of Factors to Predict the Risk of Intubation and Mortality in Patients with Severe COVID-19

In some patients, SARS-CoV-2 infection induces cytokine storm, hypercoagulability and endothelial cell activation leading to worsening of COVID-19, intubation and death. Prompt identification of patients at risk of intubation is an urgent need. Objectives. To derive a prognostic score for the risk of intubation or death in patients with COVID-19 admitted in intensive care unit (ICU), by assessing biomarkers of hypercoagulability, endothelial cell activation and inflammation and a large panel of clinical analytes. Design, Setting and Participants. A prospective, observational study enrolled 118 patients with COVID-19 admitted in the ICU. On the first day of ICU admission, all patients were assessed for biomarkers (protein C, protein S, antithrombin, D-Dimer, fibrin monomers, FVIIa, FV, FXII, FXII, FVIII, FvW antigen, fibrinogen, procoagulant phospholipid dependent clotting time, TFPI, thrombomodulin, P-selectin, heparinase, microparticles exposing TF, IL-6, complement C3a, C5a, thrombin generation, PT, aPTT, hemogram, platelet count) and clinical predictors. Main Outcomes and Measures. The clinical outcomes were intubation and mortality during hospitalization in ICU. Results: The intubation and mortality rates were 70% and 18%, respectively. The COMPASS-COVID-19-ICU score composed of P-Selectin, D-Dimer, free TFPI, TF activity, IL-6 and FXII, age and duration of hospitalization predicted the risk of intubation or death with high sensitivity and specificity (0.90 and 0.92, respectively). Conclusions and Relevance. COVID-19 is related to severe endothelial cell activation and hypercoagulability orchestrated in the context of inflammation. The COMPASS-COVID-19-ICU risk assessment model is accurate for the evaluation of the risk of mechanical ventilation and death in patients with critical COVID-19. The COMPASS-COVID-19-ICU score is feasible in tertiary hospitals and could be placed in the diagnostic procedure of personalized medical management and prompt therapeutic intervention.

Persisting Endothelial Cell Activation and Hypercoagulability after COVID-19 Recovery—The Prospective Observational ROADMAP-Post COVID-19 Study

Background. Hypercoagulable state and endothelial cell activation are common alterations in patients with COVID-19. Nevertheless, the hypothesis of persistent hypercoagulability and endothelial cell activation following recovery from COVID-19 remains an unresolved issue. Objectives. To investigate the persistence of endothelial cell activation and hypercoagulability after recovery from COVID-19. Patients/Methods. COVID-19 survivors (n = 208) and 30 healthy individuals were enrolled in this study. The following biomarkers were measured: procoagulant phospholipid-dependent clotting time (PPL-ct), D-Dimer, fibrin monomers (FM), free Tissue factor pathway inhibitor (free-TFP)I, heparinase, and soluble thrombomodulin (sTM). Antibodies against SARS-CoV-2 (IgG and IgA) were also measured. Results. The median interval between symptom onset and screening for SARS-CoV-2 antibodies was 62 days (IQR = 22 days). Survivors showed significantly higher levels of D-Dimers, FM, TFPI, and heparanase as compared to that of the control group. Survivors had significantly shorter PPL-ct. Elevated D-dimer was associated with older age. Elevated FM was associated with female gender. Elevated heparanase was independently associated with male gender. Decreased Procoag-PPL clotting time was associated with female gender. One out of four of COVID-19 survivors showed increase at least one biomarker of endothelial cell activation or hypercoagulability. Conclusions. Two months after onset of COVID-19, a significant activation of endothelial cells and in vivo thrombin generation persists in at least one out of four survivors of COVID-19. The clinical relevance of these biomarkers in the diagnosis and follow-up of patients with long COVID-19 merits to be evaluated in a prospective clinical study.

Longitudinal Trend of Plasma Concentrations of Extracellular Vesicles in Patients Hospitalized for COVID-19

Plasma concentrations of extracellular vesicles (EVs) originating from cells involved in COVID-19-associated coagulopathy (CAC), their longitudinal trend and association with clinical outcomes were evaluated. Blood samples of consecutive COVID-19 patients admitted to a medical Unit were longitudinally collected within 48 h of admission, at discharge and 30 days post-discharge. EVs were analyzed using high sensitivity flow cytometry and phospholipid-dependent clotting time (PPL). The following EVs were measured: endothelium-, platelet-, leukocyte-derived, bearing tissue factor (TF)+, angiotensin-converting enzyme (ACE2)+, platelet-derived growth factor receptor-β (PDGF-β)+ and SARS-CoV-2-nucleoprotein (NP)+. 91 patients were recruited for baseline EV analysis (mean age 67 ± 14 years, 50.5% male) and 48 underwent the longitudinal evaluation. From baseline to 30-days post-discharge, we observed significantly decreased plasma concentrations of endothelium-derived EVs (E-Selectin+), endothelium-derived bearing TF (E-Selectin+ TF+), endothelium-derived bearing ACE2 (E-Selectin+ACE2+) and leukocyte-EVs bearing TF (CD45+TF+), p < 0.001, p = 0.03, p = 0.001, p = 0.001, respectively. Conversely, platelet-derived (P-Selectin+) and leukocyte-derived EVs (CD45+) increased from baseline to 30-days post-discharge (p = 0.038 and 0.032, respectively). EVs TF+, ACE2+, PDGF-β+, and SARS-CoV-2-NP+ did not significantly change during the monitoring. PPL increased from baseline to 30-days post-discharge (+ 6.3 s, p = 0.006). P-Selectin + EVs >1,054/µL were associated with thrombosis (p = 0.024), E-Selectin + EVs ≤531/µL with worsening/death (p 0.026) and 30-days P-Selectin+ and CD45 + EVs with persistent symptoms (p < 0.0001). We confirmed increased EVs originating from cells involved in CAC at admission and discharge. EVs derived from activated pericytes and expressing SARS-CoV-2-NP were also detected. 30-days post-discharge, endothelium-EVs decreased, while platelet- and leukocyte-EVs further increased, indicating that cellular activation persists long after the acute phase.

Endothelial Cell Activation and Thrombin Generation Assessment for the Risk of Severe Early Onset Preeclampsia. the ROADMAP-EOP Study

Background The ROADMAP-EOP study aimed to identify clinically relevant biomarkers of hypercoagulability for the identification of pregnant women at risk of early onset preeclampsia worsening. Methods The ROADMAP-EOP observational single center retrospective case–control study was conducted in Greece (Centre for Human Reproduction, Genesis Athens Clinic, Athens, Greece) from July 2020 to July and enrolled pregnant women diagnosed with EOP stratified in mild EOP group (n = 34) and severe EOP group (n = 15) as well as women with uncomplicated pregnancy (control group; n = 35). All women were assessed with thromboelastometry (ROTEM®), Calibrated Automated Thrombogram®, tissue factor activity (TFa), procoagulant phospholipid dependentclotting time (Procoag-PPL®), Proteins S (PS), TFPI, D-dimer, antithrombin (AT), thrombomodulin (TM), fibrinogen, prothrombin time (PT) and activated partial thromboplastin time (aPTT). The primary study end-point was severe earlyonset preeclampsia. Principal component analysis (PCA) was performed. Results The PCA analysis showed that a score composed of the lag-time, ttPeak and Procoag-PPL accurately predicted severe EOP (sensitivity 71.4%, specificity 61.8%, and AUC of the ROC analysis 0.953). Conclusion The pilot ROADMAP-EOP shows that activation of endothelial cells and blood hypercoagulability are driven events in the worsening of EOP. Among a large panel of biomarkers and coagulation assays, thrombingeneration test and procoagulant phospholipid dependent clotting time emerged as clinically relevant for the evaluation of the risk of severe EOP. This methodology for the development of a new clinic-biological risk assessment model for prompt identification of pregnant women at risk of severe EOP must be validated in a large multi-centerprospective study.

The Compass-COVID19-ICU Study: Identification of Factors to Predict the Risk of Intubation and Mortality in Patients with Severe COVID-19

Background: In some patients, SARS-CoV-2 infection induces cytokine storm, hypercoagulability and endothelial cell activation leading to worsening of COVID-19, intubation and death. Prompt identification of patients at risk of intubation or death is un unmet need.Objective: To derive a prognostic score for the risk of intubation or death in patients with critical COVID-19 by assessing biomarkers of hypercoagulability, endothelial cell activation and inflammation and a large panel of clinical analytes.Methods: We conducted a prospective, observational monocentric study enrolling 118 patients with COVID-19 admitted in the intensive care unit. At the 1st day of ICU admission all patients were assessed for the following biomarkers : protein C, protein S, antithrombin, D-Dimer, fibrin monomers, factors VIIa, V, XII, XII, VIII, von Willebrand antigen, fibrinogen, procoagulant phospholipid dependent clotting time, TFPI, thrombomodulin, P-selectin, heparinase, microparticles exposing tissue factor, IL-6, complement C3a, C5a, thrombin generation, prothrombin time, activated partial thromboplastin time, hemogram, platelet count) and clinical predictors. The clinical outcomes were intubation and mortality during hospitalization in ICU.Results: The intubation and mortality rate were 70 % and 18% respectively. Multivariate analysis led to the derivation of the COMPASS- COVID19-ICU score composed of P-Selectin, D-Dimer, free TFPI, TF activity, IL-6 and FXII, age and duration of hospitalization. The score predicted the risk of intubation or death with high sensitivity and specificity (0.90 and 0.92, respectively).Conclusions and Relevance: Critical COVID-19 is related with severe endothelial cell activation and hypercoagulability orchestrated in the context of inflammation. The COMPASS-COVID19-ICU score is an accurate predictive model for the evaluation of the risk of mechanical ventilation and death in patients with critical COVID-19. The assessment with the COMPASS- COVID-19-ICU score is feasible in tertiary hospitals. In this context it could be placed in the diagnostic procedure of personalized medical management and prompt therapeutic intervention. DisclosuresTerpos: Novartis: Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Genesis: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; BMS: Honoraria; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; GSK: Honoraria, Research Funding. Dimopoulos: Amgen: Honoraria; BMS: Honoraria; Takeda: Honoraria; Beigene: Honoraria; Janssen: Honoraria.

Prospective Assessment of Biomarkers of Hypercoagulability in Oncological Patients and Healthcare Workers Following Vaccination Against Sars-Cov-2 with the mRNA Vaccine. the Roadmap-COVID-19-Vaccin Study

Background: COVID-19 has been associated with hypercoagulability, endothelial cell injury and frequent thrombotic complications resulting both from direct effects of the virus on the endothelium and from the ‘cytokine storm’ resulting from the host's immune response. Since the COVID-19 vaccines have been shown to effectively prevent symptomatic infection including hospital admissions and severe disease, the risk of COVID-19-related thrombosis should be expected to (almost) disappear in vaccinated individuals. However, some rare cases of venous thrombosis have been reported in individuals vaccinated with mRNA vaccines. Thus, there is a sharp contrast between the clinical or experimental data reported in the literature on COVID-19 and on the rare thrombotic events observed after the vaccination with these vaccines. This phenomenon raised some scepticism of even some fear about the safety of these vaccines which could compromise the adhesion of the citizens in the vaccination program.Aims: We conducted a prospective observational study, to explore the impact of vaccination with the BNT162b2 (Pfizer/BioNTech) on blood hypercoagulability and endothelial cell activation and to investigate if this is modified by the presence of active cancer.Methods: In total 229 subjects were prospectively included in the study from April to June 2021. Subjects were stratified in three predefined groups: 127 vaccinated patients with active cancer (VOnco group), 72 vaccinated health care workers (VHcw group) and 30 non vaccinated health individuals (Control group). Blood samples were obtained 2 days after the administration of the first dose of BNT162b2 vaccine and collected in Vacutainer® tubes (0.109 mol/L trisodium citrate). Platelet poor plasma (PPP) was prepared by double centrifugation at 2000 g for 20 minutes at room temperature and plasma aliquots were stored at -80°C until assayed. Samples of PPP were assessed for thrombin generation (TG) with PPP-Reagent® (Thrombogram-Thrombinoscope assay with PPP-Reagent®TF 5pM), E-selectin, D-dimers, (D-Di), Tissue Factor (TFa), procoagulant phospholipid-dependent clotting time (Procag-PPL) and von Willebrand factor (vWF), thrombomodulin (TM), tissue factor pathway inhibitor (TFPI), and platelet factor 4 (PF4). All assays were from Diagnostica Stago (France). The upper and lower normal limits (UNL and LNL) for each biomarker were calculated by the mean±2SD for the control group.Results: All vaccinated subjects showed significantly increased levels of PF4 (71% >UNL, p<0.001), D-Dimers (74% >UNL, p<0.01), vWF (60% >UNL, p<0.01), FVIII (62% >UNL, p<0.01) and shorter Procoag-PPL clotting time (96% <LNL, p<0.001), as compared to controls. Thrombin generation showed significantly higher Peak (60% >UNL, p<0.01), ETP (38% >UNL, p<0.01) and MRI (66% >UNL, p<0.01) but no differences in lag-time in vaccinated subjects as compared to the control group. Vaccinated subjects did not show any increase at the levels of TFa, TFPI, TM and E-selectin in comparison with the control group. The studied biomarkers were not significantly different between the VOnco and VHcw groups.Conclusion: The ROADMAP-COVID-19-Vaccine study shows that administration of the first dose of the BNT162b2 vaccine induced significant platelet activation documented by shorter Procoag-PPL associated with increased levels of PF4. Plasma hypercoagulability was less frequent in vaccinated individuals whereas there was no evidence of significant endothelial cells activation after vaccination. Interestingly, the presence of active cancer was not associated with an enhancement of platelet activation, hypercoagulability, or endothelial cell activation after the vaccination. Probably, the generated antibodies against the spike protein or lead to platelet activation in a FcyRIIa dependent manner that results in PF4 release. The implication of the mild inflammatory reaction triggered by the vaccination could be another possible pathway leading to platelet activation. Nevertheless, vaccination does not provoke endothelial activation even in patients with cancer. The findings of the ROADMAP-COVID-19-Vaccine study support the concept administration of mRNA based vaccines does not directly cause a systematic hypercoagulability. DisclosuresGligorov: Roche-Genentech: Research Funding; Novartis: Research Funding; Onxeo: Research Funding; Daichi: Research Funding; MSD: Research Funding; Eisai: Research Funding; Genomic Heatlh: Research Funding; Ipsen: Research Funding; Macrogenics: Research Funding; Pfizer: Research Funding. Terpos: Novartis: Honoraria; Janssen: Consultancy, Honoraria, Research Funding; Genesis: Consultancy, Honoraria, Research Funding; Celgene: Consultancy, Honoraria, Research Funding; BMS: Honoraria; Amgen: Consultancy, Honoraria, Research Funding; Takeda: Consultancy, Honoraria, Research Funding; Sanofi: Consultancy, Honoraria, Research Funding; GSK: Honoraria, Research Funding. Dimopoulos: Amgen: Honoraria; BMS: Honoraria; Janssen: Honoraria; Beigene: Honoraria; Takeda: Honoraria.

Procoagulant Phospholipid Dependent Clotting Time: A New Tool for the Identification of Multiple Myeloma Patients at Risk Poor Treatment Response

Background: Research has long focused on the implications of platelet, endothelial cell and blood coagulation activation in the risk of venous thromboembolism in patients with multiple myeloma (MM). Given the pivotal role of the malignant cell in coagulation activation we studied the association between biomarkers of hypercoagulability and cancer cell activity.Aim: Using data from the prospective, longitudinal observational study ROADMAP-MM CAT (PROspective Risk Assessment anD bioMArkers of hyPercoagulability for the identification of patients with Multiple Myeloma at risk for Cancer Associated Thrombosis) we aimed to identify biomarkers of cellular and plasma hypercoagulability that play a role in determining response to the anti-myeloma treatment.Methods: Newly diagnosed patients with MM were enrolled. Patients on anticoagulant treatment were excluded. A standardized clinical research form (CRF) was completed at enrollment (T0) and at 3 months post treatment initiation (T1). Blood samples were collected at the same time points. Procoagulant phospholipid-dependent clotting time (Procoag-PPL®), tissue factor activity (TFa), thrombomodulin activity (TMa), factor VIIa, factor V (FV), antithrombin (AT), fibrin monomers (FM) and D-Dimers were measured with respective assays from Diagnostica Stago (Asnieres, France) on a STA-R® analyzer (Diagnostica Stago). Plasma levels of P-Selectin and heparanase were measured with ELISA Kits from Cusabio Biotech (from CliniSciencies, France) and R&D Systems (Lille France), respectively. Samples of platelet-poor plasma (PPP) were assessed for thrombin generation (TG) with the TF 5pMPPP-Reagent® on Calibrated Automated Thrombogram (Stago, France). The control group (CG) consisted of 30 healthy age and sex-matched individuals.Results. A total of 100 treatment naïve MM patients were enrolled. Median age was 66.5±12.0 (37-88) years and 54% of the population was male. Disease stage was distributed as follows: 24.3% ISS-I, 20.4% ISS II and 55.3% ISS-III. Bortezomib-based therapy was given to 64.1% of the patients, thalidomide based in 6.8% and lenalidomide-based in 24.3%. Median time to follow up was 11.5 months. There were 16 deaths overall and mortality rate was 162/1000 person-years (median time of death since diagnosis 4.5 months, range 1-9 months). At T1, patients with stable disease (n=8) and progressive disease (n=14) were classified as non-responders. A total of 78 patients achieved at least a partial response and were classified as responders. Compared to controls at T0, MM patients showed significantly increased levels of TFa, D-Dimers and FM and significantly shorter Procoag-PPL clotting time. P-selectin levels were significantly decreased and heparanase levels significantly increased. FVIIa, FV and AT were not significantly different between patients and controls. MM patients showed significantly increased lag-time and ttPeak and significantly lower Peak, ETP and MRI as compared to the control group. TFa and D-dimer levels decreased significantly 3 months post treatment initiation (T1) whereas TMa and AT significantly decreased. At T1 thrombin generation was further attenuated (lower ETP and Peak, prolongation of ttPeak and lower MRI). Univariate analysis demonstrated that among the studied biomarkers only short PPL-ct was associated with a significantly increased risk of no response to treatment. The area under the curve (AUC) in a plot of PPL-ct against no response to treatment (receiver operator curve analysis) was 0.7 (p=0.01).Conclusion. The prospective ROADMAP-CAT multiple myeloma study demonstrates for the first time that among a large number of hypercoagulability biomarkers assessed in newly diagnosed treatment-naïve MM patients, PPL-ct, that reflects the amount of procoagulant microparticles present in plasma, is a significant predictor of poor treatment response. A prospective trial is required to evaluate the potential role of this biomarker in anti-myeloma treatment optimization. [Display omitted] DisclosuresTerpos:Amgen: Honoraria, Other: SC member, Research Funding; Takeda: Honoraria, Other: SC member, Research Funding; Genesis/Celgene: Honoraria, Other: DMC member, Research Funding; Janssen: Honoraria, Research Funding; BMS: Honoraria; Abbvie: Honoraria; GSK: Honoraria. Garderet:Takeda: Honoraria; Amgen: Honoraria.

Prospective Assessment of Clinical Risk Factors and Biomarkers of Hypercoagulability for the Identification of Patients with Lung Adenocarcinoma at Risk for Cancer Associated Thrombosis. the Observational Roadmap-CAT Study

INTRODUCTION: The aim of this prospective longitudinal study was to identify the most clinically relevant hypercoagulability biomarkers in lung adenocarcinoma patients for elaboration of an improved risk assessment model (RAM) for venous thromboembolism (VTE).METHODS: 150 ambulatory patients with lung adenocarcinoma were prospectively enrolled as well as a control group comprised of 30 healthy age & sex-matched individuals. Thrombin generation parameters, procoagulant phospholipid-dependent clotting time (Procoag-PPL), tissue factor activity (TFa), factor VIIa (FVIIa), factor V (FV), antithrombin (AT), D-Dimers (DDi), P-selectin and heparanase levels were assessed in platelet-poor plasma (PPP) at inclusion (baseline) and at the end of the 3rd chemotherapy cycle (acute phase). Cox regression analysis was used to identify independent VTE predictors.RESULTS: At baseline, patients had significantly attenuated thrombin generation, shorter Procoag-PPL, higher levels of TFa, D-Dimers and heparanase, and lower levels of FVIIa and P-selectin, compared to controls. A significant increase in Procoag-PPL, FV and FVIIa and a decrease of P-selectin levels was observed between baseline and the acute phase. Hospitalization within the last 3 months prior to assessment, time since cancer diagnosis less than 6 months, mean rate index of thrombin generation (MRI) and Procoag-PPL were independently associated with symptomatic VTE. Accordingly, a prediction model including the above parameters had improved discriminating capacity (area under the curve/AUC: 0.84).CONCLUSIONS: Ambulatory patients with lung adenocarcinoma may display pronounced blood hypercoagulability due to decreased Procoag-PPL, increased endothelial cell activation and increased degradation of fibrin. Incorporation of Procoag-PPL and MRI of thrombin generation may improve the accuracy of a VTE RAM in the above setting. DisclosuresNo relevant conflicts of interest to declare.

Differential Effects of Clopidogrel With or Without Aspirin on Platelet Reactivity and Coagulation Activation: A Randomized Trial in Healthy Volunteers

Dual antiplatelet therapy (DAPT) is standard in acute coronary syndrome but confers a bleeding risk. To compare effects of clopidogrel single antiplatelet therapy (SAPT) with clopidogrel-based DAPT on hemostatic system activation we conducted a randomized clinical trial in 44 volunteers (clopidogrel (d1: 600mg, d2-6: 150mg) ± aspirin (100mg)). Multiple electrode aggregometry-adenosine diphosphate (MEA-ADP) and MEA-arachidonic acid (MEA-AA) triggered aggregometry, vasodilator-stimulated phosphoprotein (VASP), beta thromboglobulin, p-selectin, thromboxane B2 , d-Dimer, prothrombin fragment 1.2 (f1.2), and a phospholipid-dependent clotting time were measured in venous blood. Changes are described by mean differences (Δmean (95% confidence interval (CI)) or geometric mean ratios (95% CI)). DAPT and SAPT comparably and significantly decreased MEA-ADP at 2hours (-60% vs. -63%; P=0.35, Δmean -4.9, 95% CI -15.4 to 5.5). At 24hours (-59% vs. -47%, P=0.04, Δmean -11.1, 95% CI -21.7 to -0.4]) and 8days (-61% vs. -53%, P=0.04, Δmean -11.3, 95% CI -22.0 to -0.6). Both treatments significantly reduced VASP and MEA-AA after 2hours and 8days. DAPT inhibited MEA-AA significantly stronger at 2hours (-77% vs. -30%; P<0.0001, Δmean -39.6, 95% CI -54.2 to -25.0), at 24hours (-80% vs. -27%, P<0.0001, Δmean -47.8, 95% CI -62.3 to -33.3), and 8days (-79% vs. -27%, P<0.0001, Δmean -48.9, 95% CI -62.5 to -35.4). Neither treatment significantly influenced beta thromboglobulin or p-selectin. DAPT abolished and SAPT reduced thromboxane B2 after 24hours and 8days. The d-Dimer was reduced by DAPT (0.94, 95% CI 0.89-1.00, P=0.04) at 2hours but not after 24hours and 8days. SAPT did not decrease d-Dimer. Neither treatment affected f1.2. DAPT and SAPT comparably affect platelet and coagulation activation in venous blood.

In Newly Diagnosed Multiple Myeloma Patients, Longer Procoagulant Phospholipid-Dependent Clotting Time, Higher Levels of P-Selectin, D-Dimers and Thrombin Generation Peak Are Associated with Increased Risk of Resistance to Treatment: Results of the Prospective Roadmap-MM Study

Background:Despite an increasing number of approved therapies, multiple myeloma (MM) remains an incurable disease with frequent drug resistsance. Resistance-mediating alterations are preexisting in early disease, and it is the selective pressure of antitumor therapy that promotes their clonal expansion from baseline tumor heterogeneity. Cross-talk between monoclonal plasma cells, platelets and endothelial cells enhances hypercoagulability. The prospective, longitudinal observational study ROADMAP-MM CAT (PROspective Risk Assessment anD bioMArkers of hyPercoagulability for the identification of patients with Multiple Myeloma at risk for Cancer Associated Thrombosis) was designed to explore alternative strategies for the development of risk stratification tools in patients with MM. Aim: We explored cellular and plasma hypercoagulability in newly diagnosed chemotherapy naïve MM (NDMM) patients to identify relevant biomarkers that can be used to classify patients at high risk of resistance to anti-myeloma treatment. Methods: Symptomatic NDMM were enrolled. Patients on anticoagulant treatment were excluded from the study. Study end-point was response to treatment at 3 months (T1) according the the International Myeloma Working Group response criteria. “Resistance to antimyeloma treatment” was defined as progressive disease (PD), stable disease (SD) or minor response (MR) at 3 months post treatment initiation. Blood samples were collected at inclusion. Procoagulant phospholipid-dependent clotting time (Procoag-PPL®), tissue factor activity (TFa), thrombomodulin activity (TMa), factor VIIa, factor V (FV), antithrombin (AT), fibrin monomers (FM) and D-Dimers were measured with respective assays from Diagnostica Stago (Asnieres, France) on a STA-R® analyzer (Diagnostica Stago). Plasma levels of P-Selectin and heparanase were measured with ELISA Kits from Cusabio Biotech (from CliniSciencies, France) and R&D Systems (Lille France), respectively. Samples of platelet-poor plasma (PPP) were assessed for thrombin generation (TG) with the TF 5 pM PPP-Reagent® on Calibrated Automated Thrombogram (Stago, France). Univariate logistic regression analysis examined the associations between biomarkers and treatment resistance. The cut-off values for studied biomarkers were selected based on ROC analysis. Results A total of 144 patients were enrolled (age 66.0±12.0 yrs; 53% male). Distribution of disease stage was as follows: 32% ISS I, 23% ISS II, 45% ISS III. Bone disease was present in 71% of patients and 19% of patients had high risk cytogenetic lesions. Proteasome inhibitor (PI) based therapy was given to 64% of patients, immunomodulatory drug (IMiD) based therapy in 32% and 4% received other regimens. At 3 months, 64% of patients showed treatment “resistance”. At the univariate logistic regression “resistance to treatment” was associated with longer Procoag-PPL (32.4% in patients with Procoag-PPL ≥41.7 sec vs. 12.3% in patients with Procoag-PPL <41.7 sec; OR=3.41, 95%CI: 1.45-8.03, p=0.005), higher levels of D-dimers (36.0% in patients with D-dimers ≥1.44 μg/ml vs. 14.9% in patients with D-dimers <1.44 μg/ml; OR=3.21, 95%CI: 1.43-7.22, p=0.005) and higher Peak in the thrombogram (28.1% in patients with Peak ≥181.66 nM vs. 12.5% in patients with Peak <181.66 nM; OR=2.73, 95%CI: 1.03-7.23, p=0.043). On the other hand, PD/SD/MR rate was inversely associated with P-selectin levels (14.5% in patients with ≥23477 pg/ml vs. 42.3% in patients with P-selectin <23477 pg/ml; OR=0.23, 95%CI: 0.08-0.65, p=0.005). Conclusion. The prospective ROADMAP-CAT multiple myeloma study demonstrates for the first time that biomarkers of hypercoagulablity may also be useful to identify patients likely to display resistance to treatment. Among a large number of hypercoagulability biomarkers PPL-ct, that reflects the amount of procoagulant microparticles present in plasma, thrombin generation and the levels P-Selectine and D-Dimers were found to be significant predictors of poor treatment response. A prospective trial is required to evaluate the potential role of these biomarkers in anti-myeloma treatment optimization. DisclosuresTerpos:Novartis: Honoraria; Celgene: Honoraria, Membership on an entity's Board of Directors or advisory committees; Takeda: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel Grant, Patents & Royalties; Genesis: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel Grant, Research Funding; Janssen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel Grant, Patents & Royalties; Amgen: Honoraria, Membership on an entity's Board of Directors or advisory committees, Other: Travel Grant, Research Funding. Dimopoulos:Celgene: Honoraria; Takeda: Honoraria; Bristol-Myers Squibb: Honoraria; Janssen: Honoraria; Amgen: Honoraria.

Transmission of Procoagulant Properties to Daughter Generations of Endothelial Cells upon Exposure to Cancer Cell-Derived Microparticles. a New Implication of Cancer Derived Microparticles in the Pathogenesis of Cancer Associated Thrombosis

Introduction & Objectives: Endothelium activation by cancer cell derived MPs (CaCe-dMP) is essential in pathogenesis of cancer associated thrombosis (CAT). Recent studies demonstrated that exposed endothelial cells to CaCe-dMP acquire a new procoagulant phenotype characterized by endocytosis of tissue factor (TF) and enhancement of thrombin generation.The aim of the present study was to investigate whereas the procoagulant properties acquired upon exposure of endothelial cells to CaCe-dMP are transferred to daughter generations of the endothelial cells.Materials & Methods: Pancreas adenocarcinoma cells (BXPC3) and human breast cancer cells (MCF7) were cultured in 75 cm2 culture flasks at 37˚C in a 100% humidified atmosphere with 5% CO2 and were used for experiments at a confluence of 70%. Microparticles released in conditioned medium from BXPC3 and MCF7 cells were isolated by differential centrifugation. The pellets were washed twice and re-suspended in 1 ml endothelium cell basal medium (EBM-2). Human umbilical vein endothelial cells (HUVEC) were cultured for 72 h in the presence or absence of CaCe-dMP (mother generation : C0). Subsequently, they were washed and re-cultivated over three cycles to get daughter cell generations (Daughter Generations : C1, C2, C3). Tissue factor activity (TFa) was assessed with a chromogenic assay in the absence or presence of cells in normal PPP. Procoagulant phospholipid-dependent clotting time (Proag-PPL): was measured with STA®Procoag-PPL assay. Thrombin generation was studied as described elsewhere using Calibrated Automated Thrombogram®. All assays were from Diagnostica Stago (Asnières, France).Results: The HUVEC and their microparticles manifested faint amounts of TFa (0.18±0.03 pM and 1.2±1.0 pM respectively). At steady state, HUVEC did not induce any detectable thrombin generation. Abundant TFa was showed by BXPC3-dMP (92±50 pM). The levels of TFa were significantly lower at MCF7-dMP (12.1±2.2 pM; p<0.05). Following exposure to BXPC3-dMP, the HUVEC abundantly displayed TFa as compared to non-exposed cells (25±3 pM versus 0.18±0.03 respectively; p<0.001) and showed significantly shorter Procoag-PPL® as compared to non-exposed cells (56±2 sec versus 102±10 sec. respectively ; p<0.001). HUVEC exposed to MCF7-dMP showed significantly increased TFa as compared to non-exposed cells (0.75±0.2 pM versus 0.18±0.03 respectively; p<0.001) and reduced the Procoag-PPL® clotting time as compared to non-exposed cells (65±3 sec versus 102±10 sec respectively; p<0.001). HUVEC exposed to CaCe-dMP significantly increased thrombin generation as compared to non-exposed HUVEC. Data of thrombin generation experiments are summarized in Table 1.Daughter HUVEC from mother cells exposed to CaCe-dMP exhibited significantly higher TFa as compared to daughter generations from HUVEC non-exposed to CaCe-dMPs. The high TFa was conserved in three generations of cells derived from those exposed to CaCe-dMPs (Figure 1). Daughter generations of HUVEC exposed to CaCe-dMP induced significantly higher thrombin generation as compared to that induced by daughter generations of non exposed HUVEC (Table 1). The TFa of daughter cells stemming from HUVEC exposed to BXPC3 was significantly higher as compared to that of daughter cells stemming from HUVEC exposed to MCF7 (Figure 1). The Procoag-PPL® did not significantly change in daughter HUVEC exposed to microparticles derived either from BXPC3 or MCF7.Conclusion: Upon exposure to CaCe-dMP, endothelial cells acquire a procoagulant phenotype marked by abundant TFa and enhanced thrombin generation potential. The procoagulant properties are transferred to the daughter generations of cells. These results support the concept that CaCe-dMPs lead to a procoagulant shift of endothelial cells which, upon exposure, present high TF activity and enhance thrombin generation. The procoagulant shift of endothelial cells can be transferred to next generations of endothelial cells and could be an additional mechanism - together with cancer-induced blood hypercoagulability - in the pathogenesis of cancer associated thrombosis. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Longer procoagulant phospholipid-dependent clotting time, lower endogenous thrombin potential and higher tissue factor pathway inhibitor concentrations are associated with increased VTE occurrence in patients with newly diagnosed multiple myeloma: results of the prospective ROADMAP-MM-CAT study

Venous thromboembolism (VTE) is a common complication in newly diagnosed symptomatic multiple myeloma (NDMM) patients. We explored cellular and plasma hypercoagulability in NDMM patients to identify relevant biomarkers that can be used in combination with clinical factors in the development of a risk assessment model (RAM) for VTE. Untreated patients (n = 144) with NDMM were prospectively enrolled, baseline biomarkers prior to anti-myeloma treatment and thromboprophylaxis initiation were obtained. These were compared against values in a group of healthy individuals with similar age and sex distribution. The primary study end point was symptomatic VTE occurrence. At 12-month follow-up cumulative VTE rate was 10.4%. NDMM patients showed biological signs of cellular and plasma hypercoagulability and endothelial cell activation. Procoagulant phospholipid clotting time (Procoagulant-PPL) was shorter, P-selectin levels lower and thrombin generation attenuated overall compared to healthy subjects. Longer Procoag-PPL®, lower endogenous thrombin potential (ETP), and higher levels of tissue factor pathway inhibitor (TFPI) were associated with VTE occurrence. Multivariate analysis showed that Procoag-PPL® and ETP were independent risk factors for VTE. We conclude that Procoag-PPL® and ETP can be prospectively incorporated into a RAM for VTE in MM in combination with clinical and disease risk factors.

Prospective Assessment of Clinical Risk Factors and Biomarkers of Hypercoagulability for the Identification of Patients with Lung Adenocarcinoma at Risk for Cancer-Associated Thrombosis: The Observational ROADMAP-CAT Study.

The aim of this prospective study was to identify the most clinically relevant hypercoagulability biomarkers in lung adenocarcinoma patients for elaboration of an improved risk assessment model (RAM) for venous thromboembolism (VTE). One hundred fifty ambulatory patients with lung adenocarcinoma were prospectively enrolled. Thrombin generation, procoagulant phospholipid-dependent clotting time (Procoag-PPL), tissue factor activity (TFa), factor VIIa (FVIIa), factor V (FV), antithrombin, D-Dimers, P-selectin, and heparanase levels were assessed in platelet-poor plasma at inclusion (baseline) and at the end of the third chemotherapy cycle (third chemotherapy). Cox regression analysis was used to identify independent VTE predictors. At baseline, patients had significantly attenuated thrombin generation, shorter Procoag-PPL, higher levels of TFa, D-Dimers, and heparanase, and lower levels of FVIIa and P-selectin, compared with controls. A significant increase in Procoag-PPL, FV, and FVIIa and a decrease of P-selectin levels were observed between baseline and third chemotherapy. Hospitalization within the last 3 months prior to assessment, time since cancer diagnosis less than 6 months, mean rate index (MRI) of thrombin generation, and Procoag-PPL were independently associated with symptomatic VTE. Accordingly, a prediction model including Procoag-PPL and MRI showed significant discriminating capacity (area under the curve: 0.84). Ambulatory patients with lung adenocarcinoma may display pronounced blood hypercoagulability due to decreased Procoag-PPL, increased endothelial cell activation, and increased degradation of fibrin. Incorporation of Procoag-PPL and MRI of thrombin generation may improve the accuracy of a VTE-RAM in the above setting. The prospective ROADMAP-CAT study identified two biomarkers of hypercoagulability, the procoagulant phospholipid-dependent clotting time (Procoag-PPL) and the mean rate index (MRI) of the propagation phase of thrombin generation assessed with the Calibrated Automated Thrombinoscope, as being clinically relevant for the classification of ambulatory patients with lung adenocarcinoma receiving a maximum of one cycle of chemotherapy into high and intermediate/low risk for venous thromboembolism. Measurement of Procoag-PPL and MRI within 1 month after the administration of the first chemotherapy cycle provides significant accuracy of the assessment. Association of the Procoag-PPL and MRI with the clinical risk assessment model for cancer-associated thrombosis in ambulatory patients with solid tumors (COMPASS-CAT RAM) further improved its accuracy.

Newly Diagnosed Multiple Myeloma Is Associated with Enhanced TF Pathway Activation, Thrombin Generation and Increased Concentration of Procoagulant Microparticles

Background: Multiple myeloma (MM) and plasma cell dyscrasias (PCD) are associated with increased risk of venous thromboembolism (VTE) which is further enhanced by treatments with immunomodulatory agents, melphalan or steroids. The optimization of VTE prevention in patients with MM is an unmet need. According to Virchow's triad, blood hypercoagulabilty is one of the three conditions required for thrombosis. Elaboration of a risk assessment model, which includes biomarkers of hypercoagulability, could lead to better identification of MM patients eligible for pharmacological thromboprophylaxis.Aims: We conducted a longitudinal observational study, to explore the relationship of MM with cellular and plasma hypercoagulability aiming to identify the most relevant biomarkers which could be used in the RAM for VTE.Materials and Methods: Newly diagnosed patients (n=72) with PCD were recruited from July 2014 to May 2015. The control group (CG) was consisted of 30 healthy age and sex-matched individuals. A systematic compression ultrasound was performed at baseline and 6 months post-therapy. Blood samples were obtained at time of diagnosis and at 3-6 months post therapy. Samples of platelet poor plasma were assessed for thrombin generation (TG) with the PPP-Reagent® (5pMTF and 4μM phospholipids), P-selectin, D-dimers (D-Di), activated FVII (FVIIa), Tissue Factor (TFa), fibrin monomers (FM), and procoagulant phospholipid dependent clotting time (PPL-ct). The upper and lower normal limits (UNL and LNL) were calculated by the mean±2sd. We present herein the data obtained at the inclusion of the patients.Results: Forty-three patients had MM, 16 had asymptomatic MM (AMM), 13 had MGUS. The median age was 68 years (40-84 years); 44% of patients were males. The median time to follow up was 6 months (range: 2-12 months). Patients with PCD as compared to the CG had significantly shorter PPL-ct, which it has been shown that it is inversely correlated with the concentration of platelet derived procoagulant microparticles. PCD patients had also lower Endogenous thrombin potential (ETP), shorter time to thrombin Peak (ttPeak) and lower mean rate index (MRI) of the propagation phase of TG as compared to the controls. The levels of P-selectin were not significantly different between the two groups. Patients with MM as compared to MGUS and AMM patients had significantly higher levels of TFa, FVIIa, FM, D-Di, Peak and MRI (Table 1). Among MM patients 72% had PPL-ct below the LNL, 62% and 28% had TFa and FM above the UNL respectively, 4% had MRI above the UNL and 29% had MRI below the LNL. Among patients who received therapy, 46% also received thromboprophylaxis with either aspirin (76%, n=22) or LMWH (24%, n=5); all were MM patients who received IMiD-based therapies. During the follow-up period the rate of VTE events in MM patients was 7% (all MM patients under treatment).Conclusion: In patients with PCD increased procoagulant microparticles of cellular origin is a generalized phenomenon. In addition, patients with MM present significant TF pathway activation and increased in vivo TG. A significant part, but not all of the patients present strong signs of plasma hypercoagulability. The finding of high inter-individual variability of TG underlines the heterogeneity of blood coagulation alterations in MM patients. The data of the prospective part of this study will allow to validate the clinical significance of this finding.Table 1Biomarkers of plasma and cellular hypercoagulablity in newly diagnosed patients with PCD. ETP: endogenous thrombin potential; MRI: mean rate index of the propagation phase of thrombin generation. FM: fibrin monomersParametersControls (n=30)MGUS (n=13)AMM (n=16)MM (n=43)PPL (sec)62.8±8.638.1±8.2*41.3±6.8*39.9±13.7*P-Selectin (pg/ml)62660±1039035127±1246229697.7±9090.4536223±13638FTa (ng/ml)0.3±0.12.1±1.4*1.9±1.3*7.5±23.3*$FVIIa (U/ml)50.9±10.660.2±27.564.4±48.6102.1±203.5*$FM (μg/ml)3.5±0.88.1±8.4*5.7±1.7*17.7±38.3*$D-Di (μg/ml)0.3±0.11.1±1.10.6±0.51.8±2.8*$Thrombin generationLagtime (min)2.5±0.43.4±1.23.43±0.714.2±2.3*$ETP (nM/min)1496±1911029±2051045.87±288.91202±516$Peak (nM)289±36168±60174±64216±74$ttPeak (min)5.3±0.77.3±1.87.17±1.237.1±2.7MRI110±2448±2452±2882±44$*p<0.05 versus Controls$p<0.05 versus MGUS and SMM DisclosuresVan Dreden:Diagnostica Stago: Employment. Dimopoulos:Janssen-Cilag: Honoraria; Celgene: Honoraria; Janssen: Honoraria; Novartis: Honoraria; Amgen: Honoraria; Genesis: Honoraria; Onyx: Honoraria.

Nanofiltration to remove microparticles and decrease the thrombogenicity of plasma: in vitro feasibility assessment

As plasma contains procoagulant microparticles (MPs), removing MPs by 75-nm nanofiltration may decrease plasma in vitro thrombogenicity while maintaining the hemostatic activity from coagulation factors. We defined conditions to nanofilter leukoreduced plasma on a 75-nm hollow-fiber membrane filter. Plasma quality was assessed by coagulation, immunochemical, and electrophoretic assays. MP removal was evaluated by biophysical (flow cytometry, dynamic light scattering, nanoparticle tracking analysis, and tunable resistive pulse sensing) and functional (thrombin generation assay [TGA; Technothrombin], prothrombinase [Zymuphen MP-activity], tissue factor [Zymuphen MP-TF], and procoagulant phospholipid-dependent clotting time [STA-Procoag-PPL] assays) methods. Spiking experiments using platelet MPs were performed to determine extent of removal by nanofiltration. Freshly collected leukoreduced, but not previously frozen, plasma could be readily nanofiltered on a 0.01-m2 75-nm nanofilter under conditions preserving protein and lipoprotein profile, coagulation factor content, and global coagulation activity (prothrombin time, activated partial thromboplastin time). Biophysical methods confirmed an extensive removal of MPs during nanofiltration. All functional assays indicated a marked reduction of plasma in vitro thrombogenicity. There was no thrombin generation in nanofiltered plasma tested by TGA assay with "RC-low phospholipid concentration" reagent, while it was similar to that of starting and leukoreduced plasma samples when using "RC-high phospholipid concentration" reagent. More than 9 log of MPs were removed by nanofiltration. Nanofiltration of 75 nm efficiently removes MPs and decreases in vitro thrombogenicity of plasma without affecting the protein content or the hemostatic activity of coagulation factors. Studies are needed to evaluate the impact of MP removal on in vivo thrombogenic risks and hemostatic efficacy.