A Phase 3 interventional study of Apixaban 2.5 MG and Placebo in Covid19, sponsored by Thomas L. Ortel. Completed at 121 sites in United States. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2025-02-25.
Sponsored by Thomas L. Ortel · Phase 3, Interventional, and Prevention
A multicenter, adaptive, randomized platform trial evaluating the efficacy and safety of antithrombotic strategies in patients with COVID-19 following hospital discharge
This study is an adaptive, prospective, randomized platform trial designed to compare the effectiveness and safety of antithrombotic therapy with no antithrombotic therapy after hospitalization for 48 hours or longer for COVID-19. For Stage 1 of this study, participants will be randomized to either prophylactic anticoagulation or matching placebo for 30 days, and then followed for an additional 60 days after the completion of treatment (total duration of follow-up, 90 days).
The primary objective is to determine the most effective and safe antithrombotic strategy to prevent the composite outcome of symptomatic deep vein thrombosis, pulmonary embolism, other venous thromboembolism, ischemic stroke, myocardial infarction, other arterial thromboembolism, and all-cause mortality by 30 days following discharge from the hospital.
Biobanking of samples for future biomarker and mechanistic studies will be available for centers able to participate and collect samples from eligible participants. Samples will be collected at the time of enrollment and after the completion of 30 days of therapy
7,640 studies on the registry are indexed under COVID-19; 488 are open to participants now.
This study's enrollment of 1,291 is above the median of 100 across 4,099 interventional studies indexed under COVID-19.
Browse COVID-19 studies →This is the only study on the registry with Thomas L. Ortel as lead sponsor.
Counted across the registry records on this site, refreshed daily.
Age ≥ 18 years
Exclusion Criteria:
Drug: Apixaban 2.5 MG Participants will be given study medication at the time of discharge from the hospital. Participants will take Apixaban 2.5 MG twice a day, once in the morning and once in the evening, for 30 days. Participants will be contacted (electronic or telephone) 2 days after starting the study medication and contact will continue up to day 90 after starting study treatment. Follow up will be through electronic and/or telephone contact depending on the participant's preference, compliance, and medication adherence. Participants will be queried for any clinically relevant endpoints, especially major bleeding or a need to seek healthcare attention for any reason. Follow-up will occur from the time of discharge and through the 30 day study period, with contacts 2 days, 10 days, 20 days, and 30 days after discharge. Two additional study contacts will take place 45 days and 90 days after discharge.
Drug: Apixaban 2.5 MG
Drug: Placebo Participants will be given study medication at the time of discharge from the hospital. Participants will take the Placebo twice a day, once in the morning and once in the evening, for 30 days. Participants will be contacted (electronic or telephone) 2 days after starting the study medication and contact will continue up to day 90 after starting study treatment. Follow up will be through electronic and/or telephone contact depending on the participant's preference, compliance, and medication adherence. Participants will be queried for any clinically relevant endpoints, especially major bleeding or a need to seek healthcare attention for any reason. Follow-up will occur from the time of discharge and through the 30 day study period, with contacts 2 days, 10 days, 20 days, and 30 days after discharge. Two additional study contacts will take place 45 days and 90 days after discharge.
Drug: Placebo
Participants will take Apixaban 2.5 MG twice a day, once in the morning and once in the evening for 30 days. Participants will be contacted (electronic or telephone) 2 days after starting the study medication and will continue up to day 90 after starting study treatment. Followup will occur from the time of discharge through the 30 day study period with contacts at 2 days, 10 days, 20 days and 30 days after discharge. Two additional study contacts will take place 45 days and 90 days after discharge.
Also known as: Eliquis
Participants will take placebo twice a day, once in the morning and once in the evening for 30 days. Participants will be contacted (electronic or telephone) 2 days after starting the study medication and will continue up to day 90 after starting study treatment. Followup will occur from the time of discharge through the 30 day study period with contacts at 2 days, 10 days, 20 days and 30 days after discharge. Two additional study contacts will take place 45 days and 90 days after discharge.
Composite Outcome of Symptomatic Deep Vein Thrombosis, Pulmonary Embolism, Other Venous Thromboembolism, Ischemic Stroke, Myocardial Infarction, Other Arterial Thromboembolism, and All-cause Mortality as Measured by Hospital Records.
Composite endpoint (CE) of venous and arterial thrombotic complications-including new, symptomatic proximal, or distal DVT of the upper or lower extremities, PE, and new thrombosis of other veins (including cerebral sinus and splanchnic veins), ischemic stroke, myocardial infarction, other arterial thromboembolism (e.g., mesenteric or acute limb ischemia), and all-cause mortality by day 30.
Time frame: 30 days after hospital discharge
The Composite Outcome of All-cause Mortality and the EuroQoL Group 5-Dimension (EQ5D) Index Score.
Composite endpoint of mortality and EQ5D index at Day 30. All mortality events will be considered worse than any possible EQ5D response \[QOL\&M30\]. Death was designated as a score of 0. Scores range from 0 (where 0 is the value of a health state equivalent to dead) to 1 (the value of full health), with higher scores indicating higher health utility.
Time frame: 30 days after hospital discharge
The Composite Outcome of All-cause Mortality and the EQ5D Index Score.
Composite endpoint of mortality and EQ5D index at Day 90. All mortality events will be considered worse than any possible EQ5D response. Death was designated as a score of 0. Scores range from 0 (where 0 is the value of a health state equivalent to dead) to 1 (the value of full health), with higher scores indicating higher health utility.
Time frame: 90 days after hospital discharge
The Composite Outcome of Symptomatic Deep Vein Thrombosis, Pulmonary Embolism, Other Venous Thromboembolism, Ischemic Stroke, Myocardial Infarction, Other Arterial Thromboembolism, and All-cause Mortality as Measured by Hospital Records.
Time frame: 45 days after hospital discharge
The Composite Outcome of Symptomatic Deep Vein Thrombosis, Pulmonary Embolism, Other Venous Thromboembolism, Ischemic Stroke, Myocardial Infarction, Other Arterial Thromboembolism, and All-cause Mortality as Measured by Hospital Records.
Time frame: 90 days after hospital discharge
New, Symptomatic VTE (Inclusive of DVT, PE, or Other Venous Thrombosis) for up to 30 Days After Randomization as Measured by Hospital Records.
Time frame: 30 days after randomization (which occurred at time of hospital discharge)
New, Symptomatic ATE (Inclusive of Ischemic Stroke, MI, or Peripheral Arterial Thromboembolism) for up to 30 Days After Randomization as Measured by Hospital Records.
Time frame: 30 days after randomization (which occurred at time of hospital discharge)
Percentage of Participants With All-cause Mortality
Time frame: 30 days following discharge from hospital
The Incidence of All-cause Rehospitalization for up to 90 Days After Randomization
Time frame: 90 days following discharge from hospital
The Individual Domains of EQ5D and the EQ5D Visual Analog Scale for 30 and 90 Days After Randomization
Time frame: 30 and 90 days following discharge from hospital
| Milestone | Placebo | Apixaban |
|---|---|---|
| Started | 607 | 610 |
| Completed | 581 | 578 |
| Not completed | 26 | 32 |
Composite endpoint (CE) of venous and arterial thrombotic complications-including new, symptomatic proximal, or distal DVT of the upper or lower extremities, PE, and new thrombosis of other veins (including cerebral sinus and splanchnic veins), ischemic stroke, myocardial infarction, other arterial thromboembolism (e.g., mesenteric or acute limb ischemia), and all-cause mortality by day 30.
| percentage of participants | Placebo | Apixaban |
|---|---|---|
| Composite Outcome of Symptomatic Deep Vein Thrombosis, Pulmonary Embolism, Other Venous Thromboembolism, Ischemic Stroke, Myocardial Infarction, Other Arterial Thromboembolism, and All-cause Mortality as Measured by Hospital Records. | 2.31 (1.27 to 3.84) | 2.13 (1.14 to 3.62) |
Composite endpoint of mortality and EQ5D index at Day 30. All mortality events will be considered worse than any possible EQ5D response \[QOL\&M30\]. Death was designated as a score of 0. Scores range from 0 (where 0 is the value of a health state equivalent to dead) to 1 (the value of full health), with higher scores indicating higher health utility.
| score on a scale | Placebo | Apixaban |
|---|---|---|
| The Composite Outcome of All-cause Mortality and the EuroQoL Group 5-Dimension (EQ5D) Index Score. | 0.93 (0.78 to 1.00) | 0.93 (0.75 to 1.00) |
Composite endpoint of mortality and EQ5D index at Day 90. All mortality events will be considered worse than any possible EQ5D response. Death was designated as a score of 0. Scores range from 0 (where 0 is the value of a health state equivalent to dead) to 1 (the value of full health), with higher scores indicating higher health utility.
| score on a scale | Placebo | Apixaban |
|---|---|---|
| The Composite Outcome of All-cause Mortality and the EQ5D Index Score. | 0.94 (0.76 to 1.00) | 0.94 (0.74 to 1.00) |
| percentage of participants | Placebo | Apixaban |
|---|---|---|
| The Composite Outcome of Symptomatic Deep Vein Thrombosis, Pulmonary Embolism, Other Venous Thromboembolism, Ischemic Stroke, Myocardial Infarction, Other Arterial Thromboembolism, and All-cause Mortality as Measured by Hospital Records. | 2.80 (1.64 to 4.44) | 2.46 (1.38 to 4.02) |
| percentage of participants | Placebo | Apixaban |
|---|---|---|
| The Composite Outcome of Symptomatic Deep Vein Thrombosis, Pulmonary Embolism, Other Venous Thromboembolism, Ischemic Stroke, Myocardial Infarction, Other Arterial Thromboembolism, and All-cause Mortality as Measured by Hospital Records. | 2.80 (1.64 to 4.44) | 3.11 (1.89 to 4.82) |
| percentage of participants | Placebo | Apixaban |
|---|---|---|
| New, Symptomatic VTE (Inclusive of DVT, PE, or Other Venous Thrombosis) for up to 30 Days After Randomization as Measured by Hospital Records. | 0.82 (0.27 to 1.91) | 0.82 (0.27 to 1.90) |
| percentage of participants | Placebo | Apixaban |
|---|---|---|
| New, Symptomatic ATE (Inclusive of Ischemic Stroke, MI, or Peripheral Arterial Thromboembolism) for up to 30 Days After Randomization as Measured by Hospital Records. | 0.49 (0.10 to 1.44) | 0.16 (0.00 to 0.91) |
| percentage of participants | Placebo | Apixaban |
|---|---|---|
| Percentage of Participants With All-cause Mortality | 1.48 (0.68 to 2.80) | 1.31 (0.57 to 2.57) |
Results for this outcome have not been posted.
Results for this outcome have not been posted.
Collected over Up to the 90 day visit. Non-serious events are listed at a 0% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| Apixaban | 12/610 (2%) | 71/610 (11.6%) | 80/610 (13.1%) |
| Placebo | 9/607 (1.5%) | 66/607 (10.9%) | 90/607 (14.8%) |
| Event | Apixaban | Placebo |
|---|---|---|
| WORSENING COVID-19 PNEUMONIAInfections and infestations | 10/610 | 14/607 |
| PNEUMONIAInfections and infestations | 5/610 | 5/607 |
| CHEST PAINGeneral disorders | 4/610 | 1/607 |
| WORSENING PNEUMONIAInfections and infestations | 4/610 | 3/607 |
| DIABETIC KETO ACIDOSISMetabolism and nutrition disorders | 3/610 | 1/607 |
| PULMONARY EMBOLIRespiratory, thoracic and mediastinal disorders | 3/610 | 1/607 |
| C. DIFFICILE COLITISInfections and infestations | 0/610 | 2/607 |
| CELLULITISInfections and infestations | 0/610 | 2/607 |
| COPD EXACERBATIONRespiratory, thoracic and mediastinal disorders | 2/610 | 2/607 |
| DEEP VEIN THROMBOSISVascular disorders | 2/610 | 2/607 |
| Event | Apixaban | Placebo |
|---|---|---|
| WORSENING COVID-19 PNEUMONIAInfections and infestations | 3/610 | 5/607 |
| WORSENING PNEUMONIAInfections and infestations | 1/610 | 5/607 |
| ELEVATED D-DIMERInvestigations | 0/610 | 4/607 |
| FALLInjury, poisoning and procedural complications | 4/610 | 2/607 |
| HEMOPTYSISRespiratory, thoracic and mediastinal disorders | 0/610 | 3/607 |
| URINARY TRACT INFECTIONInfections and infestations | 0/610 | 3/607 |
| CHEST PAINGeneral disorders | 3/610 | 2/607 |
| COPD EXACERBATIONRespiratory, thoracic and mediastinal disorders | 3/610 | 0/607 |
| MOTOR VEHICLE ACCIDENTInjury, poisoning and procedural complications | 0/610 | 2/607 |
| PLEURITIC CHEST PAINRespiratory, thoracic and mediastinal disorders | 0/610 | 2/607 |
| Age, Continuous(years) | Placebo | Apixaban | Total |
|---|---|---|---|
| Median | 54.1 (44 to 64) | 54.1 (44 to 64) | 54.1 (44 to 64) |
| Sex: Female, Male(Participants) | Placebo | Apixaban | Total |
|---|---|---|---|
| Female | 303 | 311 | 614 |
| Male | 304 | 299 | 603 |
| Ethnicity (NIH/OMB)(Participants) | Placebo | Apixaban | Total |
|---|---|---|---|
| Hispanic or Latino | 103 | 100 | 203 |
| Not Hispanic or Latino | 484 | 487 | 971 |
| Unknown or Not Reported | 20 | 23 | 43 |
| Race/Ethnicity, Customized(Participants) | Placebo | Apixaban | Total |
|---|---|---|---|
| White | 363 | 350 | 713 |
| Asian | 12 | 10 | 22 |
| Black or African American | 154 | 168 | 322 |
| American Indian or Alaska Native | 4 | 6 | 10 |
| Native Hawaiian or other Pacific Islander | 5 | 2 | 7 |
| Aboriginal or First Nations | 0 | 0 | 0 |
| Middle Eastern or North African | 0 | 1 | 1 |
| More than one race | 3 | 5 | 8 |
| Other Race | 20 | 23 | 43 |
| Unknown | 46 | 45 | 91 |
| Region of Enrollment(participants) | Placebo | Apixaban | Total |
|---|---|---|---|
| United States | 607 | 610 | 1217 |
| Medical history of Deep Vein Thrombosis (DVT)(Participants) | Placebo | Apixaban | Total |
|---|---|---|---|
| Count of participants | 7 | 6 | 13 |
| Medical History of Pulmonary Embolism (PE)(Participants) | Placebo | Apixaban | Total |
|---|---|---|---|
| Count of participants | 3 | 3 | 6 |
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