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Circulation ; 147(25): 1891-1901, 2023 06 20.
Article in English | MEDLINE | ID: covidwho-2318184


BACKGROUND: COVID-19 (coronavirus disease 2019) is associated with heightened risks of venous and arterial thrombosis and hospitalization due to respiratory failure. To assess whether prophylactic anticoagulation can safely reduce the frequency of venous and arterial thrombosis, hospitalization, and death in nonhospitalized patients with symptomatic COVID-19 and at least one thrombosis risk factor, we conducted the PREVENT-HD double-blind, placebo-controlled randomized trial (A Study of Rivaroxaban to Reduce the Risk of Major Venous and Arterial Thrombotic Events, Hospitalization and Death in Medically Ill Outpatients With Acute, Symptomatic COVID-19] Infection). METHODS: PREVENT-HD was conducted between August 2020 and April 2022 at 14 US integrated health care delivery networks. A virtual trial design used remote informed consent and clinical monitoring and facilitated data collection through electronic health record integration with a cloud-based research platform. Nonhospitalized patients with symptomatic COVID-19 and at least one thrombosis risk factor were enrolled and randomly assigned to either 10 mg of oral rivaroxaban or placebo daily for 35 days. The primary efficacy outcome was time to first occurrence of a composite of symptomatic venous thromboembolism, myocardial infarction, ischemic stroke, acute limb ischemia, non-central nervous system systemic arterial embolism, hospitalization, or death through day 35. The principal safety end point was International Society on Thrombosis and Hemostasis critical-site or fatal bleeding. The last study visit was on day 49. RESULTS: The study was terminated prematurely because of enrollment challenges and a lower-than-expected blinded pooled event rate. A total of 1284 patients underwent randomization with complete accrual of primary events through May 2022. No patients were lost to follow-up. The primary efficacy outcome occurred in 22 of 641 in the rivaroxaban group and 19 of 643 in the placebo group (3.4% versus 3.0%; hazard ratio, 1.16 [95% CI, 0.63-2.15]; P=0.63). No patient in either group experienced critical-site or fatal bleeding. One patient receiving rivaroxaban had a major bleed. CONCLUSIONS: The study was terminated prematurely after enrollment of 32% of planned accrual because of recruitment challenges and lower-than-expected event rate. Rivaroxaban prescribed for 35 days in nonhospitalized patients with symptomatic COVID-19 at risk for thrombosis did not appear to reduce a composite end point of venous and arterial thrombotic events, hospitalization, and death. REGISTRATION: URL: https://www. CLINICALTRIALS: gov; Unique identifier: NCT04508023.

COVID-19 , Thrombosis , Humans , Rivaroxaban/adverse effects , Outpatients , Thrombosis/epidemiology , Thrombosis/prevention & control , Hemorrhage/chemically induced , Hemorrhage/drug therapy , Hospitalization , Anticoagulants/adverse effects
Elife ; 92020 08 17.
Article in English | MEDLINE | ID: covidwho-2155739


Temporal inference from laboratory testing results and triangulation with clinical outcomes extracted from unstructured electronic health record (EHR) provider notes is integral to advancing precision medicine. Here, we studied 246 SARS-CoV-2 PCR-positive (COVIDpos) patients and propensity-matched 2460 SARS-CoV-2 PCR-negative (COVIDneg) patients subjected to around 700,000 lab tests cumulatively across 194 assays. Compared to COVIDneg patients at the time of diagnostic testing, COVIDpos patients tended to have higher plasma fibrinogen levels and lower platelet counts. However, as the infection evolves, COVIDpos patients distinctively show declining fibrinogen, increasing platelet counts, and lower white blood cell counts. Augmented curation of EHRs suggests that only a minority of COVIDpos patients develop thromboembolism, and rarely, disseminated intravascular coagulopathy (DIC), with patients generally not displaying platelet reductions typical of consumptive coagulopathies. These temporal trends provide fine-grained resolution into COVID-19 associated coagulopathy (CAC) and set the stage for personalizing thromboprophylaxis.

Betacoronavirus/isolation & purification , Blood Coagulation Disorders/diagnosis , Blood Coagulation Tests , Blood Coagulation , Clinical Laboratory Techniques , Coronavirus Infections/diagnosis , Pneumonia, Viral/diagnosis , Aged , Betacoronavirus/pathogenicity , Biomarkers/blood , Blood Coagulation Disorders/blood , Blood Coagulation Disorders/virology , COVID-19 , COVID-19 Testing , Coronavirus Infections/blood , Coronavirus Infections/virology , Disease Progression , Female , Fibrinogen/metabolism , Host Microbial Interactions , Humans , Leukocyte Count , Longitudinal Studies , Male , Middle Aged , Pandemics , Platelet Count , Pneumonia, Viral/blood , Pneumonia, Viral/virology , Predictive Value of Tests , Reproducibility of Results , Retrospective Studies , SARS-CoV-2 , Time Factors
Am Heart J ; 235: 12-23, 2021 05.
Article in English | MEDLINE | ID: covidwho-1070993


BACKGROUND: COVID-19 is associated with both venous and arterial thrombotic complications. While prophylactic anticoagulation is now widely recommended for hospitalized patients with COVID-19, the effectiveness and safety of thromboprophylaxis in outpatients with COVID-19 has not been established. STUDY DESIGN: PREVENT-HD is a double-blind, placebo-controlled, pragmatic, event-driven phase 3 trial to evaluate the efficacy and safety of rivaroxaban in symptomatic outpatients with laboratory-confirmed COVID-19 at risk for thrombotic events, hospitalization, and death. Several challenges posed by the pandemic have necessitated innovative approaches to clinical trial design, start-up, and conduct. Participants are randomized in a 1:1 ratio, stratified by time from COVID-19 confirmation, to either rivaroxaban 10 mg once daily or placebo for 35 days. The primary efficacy end point is a composite of symptomatic venous thromboembolism, myocardial infarction, ischemic stroke, acute limb ischemia, non-central nervous system systemic embolization, all-cause hospitalization, and all-cause mortality. The primary safety end point is fatal and critical site bleeding according to the International Society on Thrombosis and Haemostasis definition. Enrollment began in August 2020 and is expected to enroll approximately 4,000 participants to yield the required number of end point events. CONCLUSIONS: PREVENT-HD is a pragmatic trial evaluating the efficacy and safety of the direct oral anticoagulant rivaroxaban in the outpatient setting to reduce major venous and arterial thrombotic events, hospitalization, and mortality associated with COVID-19.

COVID-19/complications , Factor Xa Inhibitors/therapeutic use , Hospitalization , Outpatients , Rivaroxaban/therapeutic use , Thrombosis/prevention & control , Adult , COVID-19/mortality , Cause of Death , Double-Blind Method , Extremities/blood supply , Factor Xa Inhibitors/adverse effects , Female , Hemorrhage/chemically induced , Hemorrhage/mortality , Hospital Mortality , Humans , Ischemia/etiology , Ischemic Stroke/etiology , Male , Middle Aged , Myocardial Infarction/etiology , Placebos/therapeutic use , Rivaroxaban/adverse effects , Thrombosis/mortality , Venous Thromboembolism/mortality , Venous Thromboembolism/prevention & control