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Intermediate or Prophylactic-Dose Anticoagulation for Venous or Arterial Thromboembolism in Severe COVID-19

Intermediate or Prophylactic-Dose Anticoagulation for Venous or Arterial Thromboembolism in Severe COVID-19: A Cluster Based Randomized Selection Trial (IMPROVE-COVID)

Status
Completed
Phases
Phase 4
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT04367831
Acronym
IMPROVE
Enrollment
94
Registered
2020-04-29
Start date
2020-05-02
Completion date
2021-05-12
Last updated
2024-12-10

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Arterial Thrombosis, COVID-19, Venous Thromboses

Keywords

COVID-19, coronavirus, anticoagulation

Brief summary

This study is being conducted to assess the effectiveness of intermediate versus prophylactic doses of anticoagulation (blood thinners) in patients critically ill with COVID-19 in the intensive care units (ICUs) throughout the hospital. Anticoagulation is part of the patient's usual standard of care but determining the dose of anticoagulation is based on physician preference. The investigators are conducting this study (a randomized trial with adaptive design employing cluster randomization) with the support of all of the ICUs to collect data in order to determine what should be the standard of care in terms of anticoagulation in these critically ill patients. The patients care will not be altered other than the choice of anticoagulation (both approved and used throughout the hospital as standard of care) based on the ICU bed they are assigned. Patient data will be collected until discharge.

Detailed description

Hemostatic, biomarker, and inflammatory changes are common in severe manifestations of coronavirus disease 2019 (COVID-19).Such factors, as well as the bedridden status and critical illness may constitute a prothrombotic milieu, predisposing to venous and arterial thrombosis. However, the optimal antithrombotic regimen for patients with COVID-19, especially those with severe disease, remains uncertain and is currently an area of active clinical interest. Prophylactic-dose anticoagulation is generally recommended for acutely ill hospitalized patients. However, given the hemostatic abnormalities of severe COVID-19 illness, it is unknown whether more intensive anticoagulation is preferred to reduce the risk of thrombotic events, potentially mitigating microvascular and macrovascular thrombi and even disseminated intravascular coagulation (DIC). Further, the risks of therapeutic dose anticoagulation must be weighed against the bleeding risks inherent to this approach. To address this critical gap in knowledge in an area of clinical equipoise, the investigators plan to conduct a cluster-randomized trial in patients admitted to intensive care units (ICUs) in a large volume academic medical center to select the best anticoagulation intervention.

Interventions

DRUGEnoxaparin Prophylactic Dose

Prophylactic dose anticoagulation (per Columbia University Irving Medical Center (CUIMC) Guidelines): If eGFR ≥30 mL/min (stable kidney function): 1. BMI \< 40 kg/m2: Enoxaparin 40 mg SC daily 2. BMI 40 - 50 kg/m2: Enoxaparin 40 mg SC q12h 3. BMI \> 50 kg/m2: Enoxaparin 60 mg SC q12h

Unfractionated heparin infusion at 10 units/kg/hour with goal anti-Xa 0.1 -0.3U/mL.

DRUGHeparin SC

Unfractionated heparin at 5000-7500 units subcutaneous (SC) every 8 hours.

DRUGEnoxaparin/Lovenox Intermediate Dose

If estimated glomerular filtration rate (eGFR) ≥ 30 mL/min: enoxaparin 1mg/kg subcutaneous (SC) daily.

Sponsors

Columbia University
Lead SponsorOTHER

Study design

Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
SINGLE (Outcomes Assessor)

Eligibility

Sex/Gender
ALL
Age
18 Years to 80 Years
Healthy volunteers
No

Inclusion criteria

* Confirmed diagnosis of COVID-19 by reverse transcription polymerase chain reaction (RT-PCR) * New admission to eligible CUIMC ICUs within 5 days * Transfer from nonparticipating to participating ICU is eligible if otherwise meets eligibility criteria. * Patients transferred between participating ICUs will maintain initial treatment assignment. * Patients not on therapeutic anticoagulation and who were already admitted to participating ICU within 5 days of trial initiation are additionally eligible.

Exclusion criteria

* Weight under 50kg * Contraindication to anticoagulation in the opinion of the treating clinician including * overt bleeding * platelet count \<50,000 * Bleeding Academic Research Consortium (BARC) major bleeding in the past 30 days * Gastrointestinal (GI) bleeding within 3 months * history of intracranial hemorrhage * Ischemic stroke within the past 2 weeks * craniotomy/major neurosurgery within the past 30 days * cardiothoracic surgery within the past 30 days * intra-abdominal surgery within 30 days prior to enrollment * Head or spinal trauma in the last months * History of uncorrected cerebral aneurysm or arteriovenous malformation (AVM) * Intracranial malignancy * Presence of an epidural or spinal catheter * Recent major surgery within the last 14 days * Decrease in hemoglobin \>3 g/dL over the last 24 hours * Allergic reaction to anticoagulants (e.g. Heparin Induced Thrombocytopenia) as documented in the electronic health records. Extracorporeal membrane oxygenation (ECMO) support or other mechanical circulatory support. * Severe chronic liver dysfunction (history of portosystemic hypertension (HTN), esophageal varices, or Child-Pugh class C or above or similar Model For End-Stage Liver Disease (MELD) scores), abnormality in liver function tests (aspartate aminotransferase (AST), alanine aminotransferase (ALT), bilirubin) 5 times greater than upper normal limit. * A history of congenital bleeding diatheses or anatomical anomaly that predisposes to hemorrhage (e.g. hemophilia, hereditary hemorrhagic telangiectasia) * Treating physician preference for therapeutic anticoagulation * Enrollment in other concurrent trials related to anticoagulant or antiplatelet therapy * Existing treatment with therapeutic anticoagulation during the previous 7 days of hospitalization prior to ICU admission (e.g. for venous thromboembolism (VTE), atrial fibrillation, mechanical valve, etc). * Do-not-resuscitate (DNR) /do-not-intubate (DNI) or comfort measures only (CMO) orders prior to randomization.

Design outcomes

Primary

MeasureTime frameDescription
Total Number of Patients Who Were Alive and Without Venous/Thrombotic Events in ICUDischarge from ICU or 30 daysComposite of being alive and without clinically-relevant venous or arterial thrombotic events at discharge from ICU (without transfer to another ICU or palliative care unit/hospice) or at 30 days (if ICU duration lasted 30 days or longer).

Secondary

MeasureTime frameDescription
Total Number of Patients With Clinically Relevant Venous or Arterial Thrombotic Events in ICUDischarge from hospital or 30 daysComposite of being alive and with clinically relevant venous or arterial thrombotic events at discharge from ICU (without transfer to another ICU or palliative care unit/hospice) or at 30 days (if ICU duration lasted 30 days or longer).
ICU Length of StayDischarge from ICU, up to 36 daysLength of stay measured in days.
Total Number of Patients With the Need for Renal Replacement Therapy in the ICUDischarge from ICU or 30 daysThe impact of intermediate-dose anti-coagulation compared with prophylactic anti-coagulation on rates of acute kidney injury and renal recovery in the ICU will be measured with the total number of patients who need of renal replacement therapy in the ICU.
Total Number of Patients With Major Bleeding in the ICUDischarge from ICU or 30 daysMajor bleeding will be assessed by BARC criteria (\> BARC 3), also explored by International Society on Thrombosis and Haemostasis (ISTH) and Thrombolysis in Myocardial Infarction (TIMI) criteria.
Hospital Length of StayDischarge from ICU, up to 36 daysLength of stay measured in days.

Countries

United States

Participant flow

Participants by arm

ArmCount
Intervention Arm: Intermediate-dose Anticoagulation
If estimated glomerular filtration rate (eGFR) ≥ 30 mL/min: enoxaparin 1mg/kg subcutaneous (SC) daily or unfractionated heparin infusion at 10 units/kg/hour with goal anti-Xa 0.1-0.3 U/mL. If eGFR \<30 mL/min or acute kidney injury or CRRT: Unfractionated heparin infusion at 10 units/kg/hour (minimum 500 units/hour if CRRT) with goal anti-Xa 0.1-0.3 U/mL Heparin Infusion: Unfractionated heparin infusion at 10 units/kg/hour with goal anti-Xa 0.1 -0.3U/mL. Enoxaparin/Lovenox Intermediate Dose: If estimated glomerular filtration rate (eGFR) ≥ 30 mL/min: enoxaparin 1mg/kg subcutaneous (SC) daily.
46
Control Arm: Prophylaxis
Prophylactic dose anticoagulation (per Columbia University Irving Medical Center (CUIMC) Guidelines): If eGFR ≥30 mL/min (stable kidney function): 1. BMI \< 40 kg/m2: Enoxaparin 40 mg SC daily 2. BMI 40 - 50 kg/m2: Enoxaparin 40 mg SC q12h 3. BMI \> 50 kg/m2: Enoxaparin 60 mg SC q12h If eGFR \< 30 mL/min or acute kidney injury: 1. 50-120 kg: Unfractionated heparin 5000 units SC q8h 2. \>120 kg: Unfractionated heparin 7500 units SC q8h If CRRT: Unfractionated heparin infusion pre-filter at 500 units/hour Enoxaparin Prophylactic Dose: Prophylactic dose anticoagulation (per Columbia University Irving Medical Center (CUIMC) Guidelines): If eGFR ≥30 mL/min (stable kidney function): 1. BMI \< 40 kg/m2: Enoxaparin 40 mg SC daily 2. BMI 40 - 50 kg/m2: Enoxaparin 40 mg SC q12h 3. BMI \> 50 kg/m2: Enoxaparin 60 mg SC q12h Heparin SC: Unfractionated heparin at 5000-7500 units subcutaneous (SC) every 8 hours.
48
Total94

Baseline characteristics

CharacteristicIntervention Arm: Intermediate-dose AnticoagulationTotalControl Arm: Prophylaxis
Age, Continuous62.6 years
STANDARD_DEVIATION 12.2
62.9 years
STANDARD_DEVIATION 11.8
63.2 years
STANDARD_DEVIATION 11.5
Ethnicity (NIH/OMB)
Hispanic or Latino
31 Participants67 Participants36 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
15 Participants27 Participants12 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
2 Participants5 Participants3 Participants
Race (NIH/OMB)
Black or African American
3 Participants5 Participants2 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
33 Participants66 Participants33 Participants
Race (NIH/OMB)
White
8 Participants18 Participants10 Participants
Region of Enrollment
United States
46 participants94 participants48 participants
Sex: Female, Male
Female
21 Participants44 Participants23 Participants
Sex: Female, Male
Male
25 Participants50 Participants25 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
deaths
Total, all-cause mortality
10 / 4611 / 48
other
Total, other adverse events
15 / 4612 / 48
serious
Total, serious adverse events
0 / 460 / 48

Outcome results

Primary

Total Number of Patients Who Were Alive and Without Venous/Thrombotic Events in ICU

Composite of being alive and without clinically-relevant venous or arterial thrombotic events at discharge from ICU (without transfer to another ICU or palliative care unit/hospice) or at 30 days (if ICU duration lasted 30 days or longer).

Time frame: Discharge from ICU or 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Intervention Arm: Intermediate-dose AnticoagulationTotal Number of Patients Who Were Alive and Without Venous/Thrombotic Events in ICU28 Participants
Control Arm: ProphylaxisTotal Number of Patients Who Were Alive and Without Venous/Thrombotic Events in ICU31 Participants
Secondary

Hospital Length of Stay

Length of stay measured in days.

Time frame: Discharge from ICU, up to 36 days

ArmMeasureValue (MEAN)
Intervention Arm: Intermediate-dose AnticoagulationHospital Length of Stay17.78 days
Control Arm: ProphylaxisHospital Length of Stay17.73 days
Secondary

ICU Length of Stay

Length of stay measured in days.

Time frame: Discharge from ICU, up to 36 days

ArmMeasureValue (MEAN)
Intervention Arm: Intermediate-dose AnticoagulationICU Length of Stay23 days
Control Arm: ProphylaxisICU Length of Stay26 days
Secondary

Total Number of Patients With Clinically Relevant Venous or Arterial Thrombotic Events in ICU

Composite of being alive and with clinically relevant venous or arterial thrombotic events at discharge from ICU (without transfer to another ICU or palliative care unit/hospice) or at 30 days (if ICU duration lasted 30 days or longer).

Time frame: Discharge from hospital or 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Intervention Arm: Intermediate-dose AnticoagulationTotal Number of Patients With Clinically Relevant Venous or Arterial Thrombotic Events in ICU15 Participants
Control Arm: ProphylaxisTotal Number of Patients With Clinically Relevant Venous or Arterial Thrombotic Events in ICU18 Participants
Secondary

Total Number of Patients With Major Bleeding in the ICU

Major bleeding will be assessed by BARC criteria (\> BARC 3), also explored by International Society on Thrombosis and Haemostasis (ISTH) and Thrombolysis in Myocardial Infarction (TIMI) criteria.

Time frame: Discharge from ICU or 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Intervention Arm: Intermediate-dose AnticoagulationTotal Number of Patients With Major Bleeding in the ICU5 Participants
Control Arm: ProphylaxisTotal Number of Patients With Major Bleeding in the ICU5 Participants
Secondary

Total Number of Patients With the Need for Renal Replacement Therapy in the ICU

The impact of intermediate-dose anti-coagulation compared with prophylactic anti-coagulation on rates of acute kidney injury and renal recovery in the ICU will be measured with the total number of patients who need of renal replacement therapy in the ICU.

Time frame: Discharge from ICU or 30 days

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Intervention Arm: Intermediate-dose AnticoagulationTotal Number of Patients With the Need for Renal Replacement Therapy in the ICU11 Participants
Control Arm: ProphylaxisTotal Number of Patients With the Need for Renal Replacement Therapy in the ICU15 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026