Thrombosis Risk in Double Heterozygous Carriers of Factor V Leiden and Prothrombin G20210A in FinnGen and the UK Biobank

The Factor V Leiden (FVL, rs6025) and prothrombin G20210A (PTGM, rs1799963) polymorphisms are two of the most well-studied genetic risk factors for venous thromboembolism (VTE). However, double heterozygosity (DH) for FVL and PTGM remains poorly understood, with prior studies in marked disagreement about the thrombosis risk conferred by the DH genotype. Utilizing multi-dimensional data from the UK Biobank (UKB) and the FinnGen biorepositories, we evaluated the clinical impact of DH carrier status across 937,939 individuals. We found that 662 participants (0.07%) were DH carriers. After adjustment for age, sex, and ancestry, DH individuals experienced a markedly elevated risk of VTE compared to wild-type individuals (OR=5.24, 95% CI: 4.01 - 6.84; P=4.8 x 10-34), which approximated the risk conferred by FVL homozygosity. A secondary analysis restricted to UKB participants (N=445,144) found that effect size estimates for the DH genotype remained largely unchanged (OR=4.53, 95% CI: 3.42 - 5.90; P<1 x 10-16) after adjustment for commonly cited VTE risk factors such as body mass index, blood type, and markers of inflammation. By contrast, the DH genotype was not associated with a significantly higher risk of any arterial thrombosis phenotype, including stroke, myocardial infarction, and peripheral artery disease. In summary, we leveraged population-scale genomic datasets to conduct the largest study to date of the DH genotype and were able to establish far more precise effect size estimates than previously possible. Our findings indicate that the DH genotype may occur as frequently as FVL homozygosity and confers a similarly increased risk of VTE.

The dos, don'ts, and nuances of thrombophilia testing

Considerable progress has been made in elucidating genetic and biologic risk factors for venous thromboembolism (VTE). Despite being able to identify heritable defects in a substantial proportion of patients with VTE, testing has not, in general, proven useful in management. Despite efforts to reduce inappropriate testing, it often falls to the hematologist to consult on patients having undergone thrombophilia testing. Through a series of cases, we discuss how D-dimer testing can be helpful in VTE recurrence risk stratification in younger women as well as how to approach patients with persistently elevated D-dimer levels in the absence of thrombosis. While elevated factor VIII coagulant activity levels are a significant risk factor for a first episode of VTE, its biologic basis is not fully understood, and studies have not shown it to be a useful predictor of recurrence. Abnormal results of genetic tests for methylene tetrahydrofolate reductase or plasminogen activator 1 promoter polymorphisms may be encountered, which carry little if any thrombotic risk and should never be ordered. We also discuss protein S deficiency, the most difficult of the hereditary thrombophilias to diagnose due to a wider "normal" range in the general population as compared with protein C, the presence of both free and bound forms in plasma, and the characteristics of the various assays in use. We also present a rare type of protein C deficiency that can be missed by functional assays using an amidolytic rather than a clotting end point.

Periprocedural management of type 2N von Willebrand disease with efanesoctocog alfa

Type 2 Normandy von Willebrand disease (type 2N VWD) is a rare qualitative defect in von Willebrand factor (VWF) that results in impaired factor VIII (FVIII) binding and consequently reduced FVIII levels. Current perioperative strategies require VWF concentrates to attain durable hemostatic FVIII levels. This case highlights the successful perioperative management of a 78-year-old female with type 2N VWD and coronary artery disease utilizing efanesoctocog alfa, a novel long-acting recombinant FVIII product approved for hemophilia A. By decoupling the FVIII-VWF interaction, efanesoctocog alfa achieves prolonged FVIII circulation independent of VWF. A single administration targeting 90% FVIII levels yielded sustained FVIII elevation without achieving supraphysiologic VWF levels, thus mitigating potential cardiovascular risks. This is the first report of efanesoctocog alfa use in type 2N VWD. Further clinical studies are necessary to corroborate its efficacy and safety for this indication.

Four-factor prothrombin complex concentrate plus andexanet alfa for reversal of factor Xa inhibitor-associated bleeding: Case series

DISCLAIMER

In an effort to expedite the publication of articles related to the COVID-19 pandemic, AJHP is posting these manuscripts online as soon as possible after acceptance. Accepted manuscripts have been peer-reviewed and copyedited, but are posted online before technical formatting and author proofing. These manuscripts are not the final version of record and will be replaced with the final article (formatted per AJHP style and proofed by the authors) at a later time.

PURPOSE

To manage factor Xa (FXa) inhibitor-associated bleeding, andexanet alfa or 4-factor prothrombin concentrate (4F-PCC) has been used to restore hemostasis. However, literature on the outcomes for patients who received both andexanet alfa and 4F-PCC is limited.

SUMMARY

We report a case series of 5 patients who received andexanet alfa plus 4F-PCC for reversal of FXa inhibitor-associated bleeding. Patients were included in this case series if they received both andexanet alfa and 4F-PCC for reversal of FXa inhibitor-associated bleeding. They were followed to either discharge or death, and in-hospital complications related to concurrent use of andexanet alfa and 4F-PCC were documented. We report an incidence of thromboembolism of 40% (2 of 5 cases) and an in-hospital mortality rate of 60% (3 of 5 cases). Taking these cases together with those in the existing literature, we found a total of 23 reported cases of safety outcomes with andexanet alfa plus 4F-PCC. The overall incidence of thromboembolism was 35% (8 of 23 cases).

CONCLUSION

This case series adds to the limited literature describing the outcomes for patients receiving andexanet alfa plus 4F-PCC. We encourage other institutions to report safety data on administering both agents.

Aspirin thromboprophylaxis in joint replacement surgery

BACKGROUND

Aspirin is commonly used as the only pharmacologic agent for prevention of venous thromboembolism (VTE) after joint replacement surgery in the United States. Despite this, prospective studies investigating VTE events after aspirin-only thromboprophylaxis in joint replacement surgery are lacking in the real-world setting.

OBJECTIVES

The aim of this study was to estimate the risk of VTE with aspirin-only pharmacologic prophylaxis following joint replacement surgery.

METHODS

We carried out a prospective observational study of 350 low-risk patients (no prior history of VTE and low cardiovascular risk factors) who underwent total knee and total hip arthroplasty and received only aspirin for thromboprophylaxis postoperatively.

RESULTS

The observed risk of symptomatic VTE was 1.7% (95% confidence interval, 0.9%-3.3%) over 3 months of follow up, with only one major bleeding event and no surgical hematomas.

CONCLUSION

The risk of VTE with aspirin monotherapy for thromboprophylaxis in joint replacement surgery in this real-world cohort was higher than previously reported.

Thromboembolism in ALK+ and ROS1+ NSCLC patients: A systematic review and meta-analysis

INTRODUCTION

Increased thromboembolism (TE) has been reported in ALK+ and ROS1+ non-small cell lung cancer (NSCLC).

MATERIALS AND METHODS

Odds ratios (OR) and hazard ratios (HR) of TE were calculated from meta-analysis and time-to-event analysis respectively for either ALK+ or ROS1+ NSCLC patients.

RESULTS

We identified eight studies (766 ALK+, 143 ROS1+, 2314 non-ALK+ and non-ROS1+ NSCLC patients) for the meta-analysis. For ALK+ NSCLC, the pooled OR was 2.00 (95% CI: 1.60-2.50) for total TE (TTE) by random-effects model, 2.10 (95% CI: 1.70-2.60) for venous thromboembolism (VTE), and 1.24 (95% CI: 0.80-1.91) for arterial thromboembolism (ATE). For ROS1+ NSCLC, the pooled OR was 3.08 (95% CI: 1.95-4.86) for TTE, and 3.15 (95% CI: 1.83-5.43) for VTE. Six studies (739 ALK+, 137 ROS1+, 561 EGFR+, 714 "wildtype" NSCLC patients) were included in the time-to-event analysis. The TTE incidence rate was 17.4 (95% CI: 15.3-19.5) per 100 pateint-years for ALK+ NSCLC, and 32.1 (95% CI: 24.6-39.6) per 100 patient-years for ROS1+ NSCLC with a 50 % cumulative incidence rate at year 3 of diagnosis. HR for TTE was 2.35 (95% CI: 1.90-2.92, p < 0.001) and 3.23 (95% CI: 2.40-4.34, p < 0.001) for ALK+ and ROS1+ NSCLC, respectively. Comparing ROS1+ NSCLC to ALK+ NSCLC, HR for TTE was 1.37 (95% CI: 1.05-1.79, p = 0.020).

CONCLUSIONS

ALK+ and ROS1+ NSCLC patients had an increased risk of TE. ROS1+ NSCLC had further increased risk of TE over ALK+ NSCLC.

Thrombosis, Bleeding, and the Observational Effect of Early Therapeutic Anticoagulation on Survival in Critically Ill Patients With COVID-19

BACKGROUND

Hypercoagulability may be a key mechanism of death in patients with coronavirus disease 2019 (COVID-19).

OBJECTIVE

To evaluate the incidence of venous thromboembolism (VTE) and major bleeding in critically ill patients with COVID-19 and examine the observational effect of early therapeutic anticoagulation on survival.

DESIGN

In a multicenter cohort study of 3239 critically ill adults with COVID-19, the incidence of VTE and major bleeding within 14 days after intensive care unit (ICU) admission was evaluated. A target trial emulation in which patients were categorized according to receipt or no receipt of therapeutic anticoagulation in the first 2 days of ICU admission was done to examine the observational effect of early therapeutic anticoagulation on survival. A Cox model with inverse probability weighting to adjust for confounding was used.

SETTING

67 hospitals in the United States.

PARTICIPANTS

Adults with COVID-19 admitted to a participating ICU.

MEASUREMENTS

Time to death, censored at hospital discharge, or date of last follow-up.

RESULTS

Among the 3239 patients included, the median age was 61 years (interquartile range, 53 to 71 years), and 2088 (64.5%) were men. A total of 204 patients (6.3%) developed VTE, and 90 patients (2.8%) developed a major bleeding event. Independent predictors of VTE were male sex and higher D-dimer level on ICU admission. Among the 2809 patients included in the target trial emulation, 384 (11.9%) received early therapeutic anticoagulation. In the primary analysis, during a median follow-up of 27 days, patients who received early therapeutic anticoagulation had a similar risk for death as those who did not (hazard ratio, 1.12 [95% CI, 0.92 to 1.35]).

LIMITATION

Observational design.

CONCLUSION

Among critically ill adults with COVID-19, early therapeutic anticoagulation did not affect survival in the target trial emulation.

PRIMARY FUNDING SOURCE

None.

Thrombolytic therapy in acute venous thromboembolism

Although anticoagulation remains the mainstay of treatment of acute venous thromboembolism (VTE), the use of thrombolytic agents or thrombectomy is required to immediately restore blood flow to thrombosed vessels. Nevertheless, systemic thrombolysis has not clearly been shown to improve outcomes in patients with large clot burdens in the lung or legs as compared with anticoagulation alone; this is in part due to the occurrence of intracranial hemorrhage in a small percentage of patients to whom therapeutic doses of a thrombolytic drug are administered. Algorithms have been developed to identify patients at high risk for poor outcomes resulting from large clot burdens and at low risk for major bleeding in an effort to improve outcomes in those receiving thrombolytic therapy. In acute pulmonary embolism (PE), hemodynamic instability is the key determinant of short-term survival and should prompt consideration of immediate thrombolysis. In hemodynamically stable PE, systemic thrombolysis is not recommended and should be used as rescue therapy if clinical deterioration occurs. Evidence is accumulating regarding the efficacy of administering reduced doses of thrombolytic agents systemically or via catheters directly into thrombi in an effort to lower bleed rates. In acute deep venous thrombosis, catheter-directed thrombolysis with thrombectomy can be used in severe or limb-threatening thrombosis but has not been shown to prevent postthrombotic syndrome. Because the management of acute VTE can be complex, having a rapid-response team (ie, PE response team) composed of physicians from different specialties may aid in the management of severely affected patients.

Changes in Care for Acute Pulmonary Embolism Through A Multidisciplinary Pulmonary Embolism Response Team

BACKGROUND

Optimal management of acute pulmonary embolism requires expertise offered by multiple subspecialties. As such, pulmonary embolism response teams (PERTs) have increased in prevalence, but the institutional consequences of a PERT are unclear.

METHODS

We compared all patients that presented to our institution with an acute pulmonary embolism in the 3 years prior to and 3 years after the formation of our PERT. The primary outcome was in-hospital pulmonary embolism-related mortality before and after the formation of the PERT. Sub-analyses were performed among patients with elevated-risk pulmonary embolism.

RESULTS

Between August 2012 and August 2018, 2042 patients were hospitalized at our institution with acute pulmonary embolism, 884 (41.3%) pre-PERT implementation and 1158 (56.7%) post-PERT implementation, of which 165 (14.2%) were evaluated by the PERT. There was no difference in pulmonary embolism-related mortality between the two time periods (2.6% pre-PERT implementation vs 2.9% post-PERT implementation, P = .89). There was increased risk stratification assessment by measurement of cardiac biomarkers and echocardiograms post-PERT implementation. Overall utilization of advanced therapy was similar between groups (5.4% pre-PERT implementation vs 5.4% post-PERT implementation, P = 1.0), with decreased use of systemic thrombolysis (3.8% pre-PERT implementation vs 2.1% post-PERT implementation, P = 0.02) and increased catheter-directed therapy (1.3% pre-PERT implementation vs 3.3% post-PERT implementation, P = 0.05) post-PERT implementation. Inferior vena cava filter use decreased after PERT implementation (10.7% pre-PERT implementation vs 6.9% post-PERT implementation, P = 0.002). Findings were similar when analyzing elevated-risk patients.

CONCLUSION

Pulmonary embolism response teams may increase risk stratification assessment and alter application of advanced therapies, but a mortality benefit was not identified.

Optical characterization of the on-target OMEGA focal spot at high energy using the full-beam in-tank diagnostic

The full-beam in-tank (FBIT) diagnostic has been deployed to directly measure the target-plane beam fluence profile, when operated at high energy, of the OMEGA Laser System at the University of Rochester's Laboratory for Laser Energetics. This paper presents the results of early measurements taken with this diagnostic and discusses an improvement that has overcome performance limitations discovered during the initial testing. The diagnostic gives new insight into the ability of the OMEGA Laser System to provide uniform fluence profiles that are consistent across all 60 beams in the laser. The ultimate goal of the FBIT diagnostic is to allow accurate assessment of the fluence uniformity on a spherical target in 60-beam implosion experiments.

Incidence of thrombosis and hemorrhage in hospitalized cancer patients with COVID-19

BACKGROUND

Coronavirus disease-2019 (COVID-19) is a recognized prothrombotic state. Patients hospitalized with active cancer are predisposed to thrombosis but whether active cancer further amplifies thrombotic risk with COVID-19 is not known.

OBJECTIVES

To evaluate cumulative incidences of thrombotic and hemorrhagic events in hospitalized COVID-19 patients with and without active cancer at 28 days.

METHODS

A retrospective cohort analysis of consecutive adults hospitalized with COVID-19 was performed. Active cancer required cancer-directed therapy within previous 6 months. The cumulative incidences of thrombosis or hemorrhage were estimated considering death as a competing risk.

RESULTS

Patients without cancer (n = 353) and active cancer (n = 45) were comparable in terms of age, sex, antibiotics administered, length of hospitalization, and critical care. The most common malignancies were lymphoid (17.8%), gastrointestinal (15.6%), lung (13.3%), and genitourinary (13.3%). At day 28, the cumulative incidence of thrombotic events was 18.2% (95% confidence interval [CI], 10.2%-27.9%) in the non-cancer cohort and 14.2% (95% CI, 4.7%-28.7%) in the cancer cohort. The cumulative incidence of major and fatal bleeding at day 28 was 20.8% (95% CI, 12.1%-31.0%) in the non-cancer group and 19.5% (95% CI, 5.5%-39.8%) in the cancer cohort. Three patients experienced fatal bleeds, all of whom were in the non-cancer cohort. Survival was significantly shorter in the group with active cancer (P = .038).

CONCLUSIONS

We observed a similarly high incidence of thrombosis and bleeding among patients admitted with COVID-19 with or without active cancer.

Extrapulmonary manifestations of COVID-19

Although COVID-19 is most well known for causing substantial respiratory pathology, it can also result in several extrapulmonary manifestations. These conditions include thrombotic complications, myocardial dysfunction and arrhythmia, acute coronary syndromes, acute kidney injury, gastrointestinal symptoms, hepatocellular injury, hyperglycemia and ketosis, neurologic illnesses, ocular symptoms, and dermatologic complications. Given that ACE2, the entry receptor for the causative coronavirus SARS-CoV-2, is expressed in multiple extrapulmonary tissues, direct viral tissue damage is a plausible mechanism of injury. In addition, endothelial damage and thromboinflammation, dysregulation of immune responses, and maladaptation of ACE2-related pathways might all contribute to these extrapulmonary manifestations of COVID-19. Here we review the extrapulmonary organ-specific pathophysiology, presentations and management considerations for patients with COVID-19 to aid clinicians and scientists in recognizing and monitoring the spectrum of manifestations, and in developing research priorities and therapeutic strategies for all organ systems involved.

Dose-adjusted enoxaparin thromboprophylaxis in hospitalized cancer patients: a randomized, double-blinded multicenter phase 2 trial

Hospitalized patients with cancer are at an increased risk of developing venous thromboembolism (VTE). The recommendation for routine pharmacologic thromboprophylaxis in hospitalized patients with cancer to prevent VTE is based on extrapolation of results from noncancer cohorts. There are limited data to support the efficacy and safety of fixed-dose low-molecular-weight heparin (LMWH) regimens in high-risk hospitalized patients with cancer. We conducted a randomized, double-blinded, phase 2 trial in hospitalized patients with active cancer at high risk of developing VTE based on Padua risk score. Patients were randomly assigned to fixed-dose enoxaparin (40 mg daily) vs weight-adjusted enoxaparin (1 mg/kg daily) during hospitalization. The primary objectives were to evaluate the safety of dose-adjusted enoxaparin and evaluate the incidence of VTE with fixed-dose enoxaparin. Blinded clinical assessments were performed at day 14, and patients randomly assigned to fixed-dose enoxaparin subsequently underwent a bilateral lower extremity ultrasound. A total of 50 patients were enrolled and randomized. The median weight of patients enrolled in weight-adjusted enoxaparin arm was 76 kg (range, 60.9-124.5 kg). There were no major hemorrhages or symptomatic VTE in either arm. At time of completion of the blinded clinical assessment, there was only 1 incidentally identified pulmonary embolus that occurred in the weight-adjusted arm. In the group randomly assigned to fixed-dose enoxaparin who subsequently underwent surveillance ultrasound, the cumulative incidence of DVT was 22% (90% binomial confidence interval, 0%-51.3%). This phase 2 trial confirms a high incidence of asymptomatic VTE among high-risk hospitalized patients with cancer and that weight-adjusted LMWH thromboprophylaxis is feasible and well-tolerated. This trial was registered at www.clinicaltrials.gov as #NCT02706249.

Should You Treat This Acutely Ill Medical Inpatient With Venous Thromboembolism Chemoprophylaxis?: Grand Rounds Discussion From Beth Israel Deaconess Medical Center

Venous thromboembolism (VTE), which includes both deep venous thrombosis and pulmonary embolism, is a common and potentially fatal condition. Medical inpatients are at high risk for VTE because of immobility as well as acute and chronic illness. Several randomized trials demonstrated that chemoprophylaxis, or low-dose anticoagulation, prevents VTE in selected medical inpatients. The 2018 American Society of Hematology clinical practice guideline on prophylaxis for hospitalized and nonhospitalized medical patients conditionally recommends chemoprophylaxis for non-critically ill medical inpatients, leaving much to the discretion of the treating physician. Here, 2 experts, a hematologist and a hospitalist, reflect on the care of a woman hospitalized with a rheumatologic disorder. They consider the risks and benefits of chemoprophylaxis, discuss VTE risk stratification, and recommend which patients should receive chemoprophylaxis and with which agents.

Long-term risk of recurrence in patients with a first unprovoked venous thromboembolism managed according to d-dimer results; A cohort study

Essentials Long-term recurrence risk after a first unprovoked VTE with negative d-dimer levels is uncertain. Anticoagulation was stopped if d-dimer was negative, and was continued if d-dimer was positive. Five years after stopping anticoagulants, recurrent VTE was 30% in men and 17% in women. Negative d-dimers do not justify stopping anticoagulants in most men but appear to in most women.

BACKGROUND

The long-term risk of recurrence in patients with a first unprovoked venous thromboembolism (VTE) who have negative d-dimer results is uncertain.

OBJECTIVES

To determine this risk, including in subgroups based on sex.

PATIENTS AND METHODS

ln a prospective interventional cohort study of 410 patients with a first unprovoked VTE, anticoagulants were stopped if d-dimer was negative on therapy and 1 month after stopping therapy. Other patients remained on anticoagulant therapy. We previously reported findings after a mean of 2.2 years. The current report includes 3 years of additional follow-up in 293 of these patients.

RESULTS

During a median follow-up of 5.0 years, recurrent VTE after stopping therapy in response to negative d-dimer testing was 5.1% (95% confidence interval [CI], 3.6-6.5) per patient-year overall, 7.5% (95% CI, 5.5-10.0) in men, 3.8% (95% CI, 2.0-6.6) in women with VTE not associated with estrogens, and 0.4% (95% CI, 0.0-2.3) in women with VTE associated with estrogens (P < 0.001 for three-group comparison). Risk of recurrence at 5 years was 21.5% (95% CI, 16.4-26.5) overall, 29.7% (95% CI, 22.1-37.3) in men, 17.0% (95% CI, 8.1-25.9) in non-estrogen women, and 2.3% (95% CI, 0.0-6.8) in estrogen women.

CONCLUSION

The long-term risk of recurrence in patients with a first unprovoked VTE who have negative d-dimer results is not low enough to justify stopping anticoagulant therapy in men, but appears to be low enough in women for many to choose stopping therapy (ClinicalTrials.gov; NCT00720915).

Rivaroxaban for Thromboprophylaxis in High-Risk Ambulatory Patients with Cancer

BACKGROUND

Ambulatory patients receiving systemic cancer therapy are at varying risk for venous thromboembolism. However, the benefit of thromboprophylaxis in these patients is uncertain.

METHODS

In this double-blind, randomized trial involving high-risk ambulatory patients with cancer (Khorana score of ≥2, on a scale from 0 to 6, with higher scores indicating a higher risk of venous thromboembolism), we randomly assigned patients without deep-vein thrombosis at screening to receive rivaroxaban (at a dose of 10 mg) or placebo daily for up to 180 days, with screening every 8 weeks. The primary efficacy end point was a composite of objectively confirmed proximal deep-vein thrombosis in a lower limb, pulmonary embolism, symptomatic deep-vein thrombosis in an upper limb or distal deep-vein thrombosis in a lower limb, and death from venous thromboembolism and was assessed up to day 180. In a prespecified supportive analysis involving the same population, the same end point was assessed during the intervention period (first receipt of trial agent to last dose plus 2 days). The primary safety end point was major bleeding.

RESULTS

Of 1080 enrolled patients, 49 (4.5%) had thrombosis at screening and did not undergo randomization. Of the 841 patients who underwent randomization, the primary end point occurred in 25 of 420 patients (6.0%) in the rivaroxaban group and in 37 of 421 (8.8%) in the placebo group (hazard ratio, 0.66; 95% confidence interval [CI], 0.40 to 1.09; P = 0.10) in the period up to day 180. In the prespecified intervention-period analysis, the primary end point occurred in 11 patients (2.6%) in the rivaroxaban group and in 27 (6.4%) in the placebo group (hazard ratio, 0.40; 95% CI, 0.20 to 0.80). Major bleeding occurred in 8 of 405 patients (2.0%) in the rivaroxaban group and in 4 of 404 (1.0%) in the placebo group (hazard ratio, 1.96; 95% CI, 0.59 to 6.49).

CONCLUSIONS

In high-risk ambulatory patients with cancer, treatment with rivaroxaban did not result in a significantly lower incidence of venous thromboembolism or death due to venous thromboembolism in the 180-day trial period. During the intervention period, rivaroxaban led to a substantially lower incidence of such events, with a low incidence of major bleeding. (Funded by Janssen and others; CASSINI ClinicalTrials.gov number, NCT02555878.).

Targeting protein disulfide isomerase with the flavonoid isoquercetin to improve hypercoagulability in advanced cancer

BACKGROUND

Protein disulfide isomerase (PDI) is a thiol isomerase secreted by vascular cells that is required for thrombus formation. Quercetin flavonoids inhibit PDI activity and block platelet accumulation and fibrin generation at the site of a vascular injury in mouse models, but the clinical effect of targeting extracellular PDI in humans has not been studied.

METHODS

We conducted a multicenter phase II trial of sequential dosing cohorts to evaluate the efficacy of targeting PDI with isoquercetin to reduce hypercoagulability in cancer patients at high risk for thrombosis. Patients received isoquercetin at 500 mg (cohort A, n = 28) or 1000 mg (cohort B, n = 29) daily for 56 days, with laboratory assays performed at baseline and the end of the study, along with bilateral lower extremity compression ultrasound. The primary efficacy endpoint was a reduction in D-dimer, and the primary clinical endpoint included pulmonary embolism or proximal deep vein thrombosis.

RESULTS

The administration of 1000 mg isoquercetin decreased D-dimer plasma concentrations by a median of -21.9% (P = 0.0002). There were no primary VTE events or major hemorrhages observed in either cohort. Isoquercetin increased PDI inhibitory activity in plasma (37.0% in cohort A, n = 25, P < 0.001; 73.3% in cohort B, n = 22, P < 0.001, respectively). Corroborating the antithrombotic efficacy, we also observed a significant decrease in platelet-dependent thrombin generation (cohort A median decrease -31.1%, P = 0.007; cohort B median decrease -57.2%, P = 0.004) and circulating soluble P selectin at the 1000 mg isoquercetin dose (median decrease -57.9%, P < 0.0001).

CONCLUSIONS

Isoquercetin targets extracellular PDI and improves markers of coagulation in advanced cancer patients.

TRIAL REGISTRATION

Clinicaltrials.gov NCT02195232.

FUNDING

Quercegen Pharmaceuticals; National Heart, Lung, and Blood Institute (NHLBI; U54HL112302, R35HL135775, and T32HL007917); and NHLBI Consortium Linking Oncology and Thrombosis (U01HL143365).

Tripled yield in direct-drive laser fusion through statistical modelling

Focusing laser light onto a very small target can produce the conditions for laboratory-scale nuclear fusion of hydrogen isotopes. The lack of accurate predictive models, which are essential for the design of high-performance laser-fusion experiments, is a major obstacle to achieving thermonuclear ignition. Here we report a statistical approach that was used to design and quantitatively predict the results of implosions of solid deuterium-tritium targets carried out with the 30-kilojoule OMEGA laser system, leading to tripling of the fusion yield to its highest value so far for direct-drive laser fusion. When scaled to the laser energies of the National Ignition Facility (1.9 megajoules), these targets are predicted to produce a fusion energy output of about 500 kilojoules-several times larger than the fusion yields currently achieved at that facility. This approach could guide the exploration of the vast parameter space of thermonuclear ignition conditions and enhance our understanding of laser-fusion physics.