Trial · NCT04650087

COVID-19 Thrombosis Prevention Trials: Post-hospital Thromboprophylaxis

NCT04650087, Phase 3, Completed, Thomas L. Ortel; results first posted 2025-02-25

3 sourcestrials-2026-11-12-0.5.0

Cite this record

ConductScience Library. COVID-19 Thrombosis Prevention Trials: Post-hospital Thromboprophylaxis. Trials, record NCT04650087. Release trials-2026-11-12-0.5.0, 12 Nov 2026. https://conductscience.org/library/trials/NCT04650087

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Trial

As registered on ClinicalTrials.gov, in the graph's capture of the registry.

Title: COVID-19 Thrombosis Prevention Trials: Post-hospital Thromboprophylaxis
NCT number: NCT04650087
Status: Completed
Phases: Phase 3
Enrollment: 1,291 participants, actual
Lead sponsor: Thomas L. Ortel
Conditions: Covid19
Interventions: Apixaban 2.5 MG, Placebo
First posted: 2020-12-02
Last updated: 2025-02-25
Results first posted: 2025-02-25

Source ClinicalTrials.gov

Registered outcomes10

Each outcome the trial registered, primary first, in ClinicalTrials.gov's words.

List	Outcome	Time frame	Description
Primary	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.	30 days after hospital discharge	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.
Secondary	The Composite Outcome of All-cause Mortality and the EuroQoL Group 5-Dimension (EQ5D) Index Score.	30 days after hospital discharge	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.
Secondary	The Composite Outcome of All-cause Mortality and the EQ5D Index Score.	90 days after hospital discharge	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.
Secondary	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.	45 days after hospital discharge
Secondary	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.	90 days after hospital discharge
Secondary	New, Symptomatic VTE (Inclusive of DVT, PE, or Other Venous Thrombosis) for up to 30 Days After Randomization as Measured by Hospital Records.	30 days after randomization (which occurred at time of hospital discharge)
Secondary	New, Symptomatic ATE (Inclusive of Ischemic Stroke, MI, or Peripheral Arterial Thromboembolism) for up to 30 Days After Randomization as Measured by Hospital Records.	30 days after randomization (which occurred at time of hospital discharge)
Other	Percentage of Participants With All-cause Mortality	30 days following discharge from hospital
Other	The Incidence of All-cause Rehospitalization for up to 90 Days After Randomization	90 days following discharge from hospital
Other	The Individual Domains of EQ5D and the EQ5D Visual Analog Scale for 30 and 90 Days After Randomization	30 and 90 days following discharge from hospital

Source ClinicalTrials.gov

Outcomes10

Each outcome the trial posted results for, in ClinicalTrials.gov's words.

Type	Outcome	Time frame	Population	Units	Measured as
PRIMARY	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.	30 days after hospital discharge	intention-to-treat (ITT) population, including all participants randomized	percentage of participants	NUMBER
SECONDARY	The Composite Outcome of All-cause Mortality and the EuroQoL Group 5-Dimension (EQ5D) Index Score.	30 days after hospital discharge	intention-to-treat (ITT) population, including all participants randomized	score on a scale	MEDIAN
SECONDARY	The Composite Outcome of All-cause Mortality and the EQ5D Index Score.	90 days after hospital discharge	intention-to-treat (ITT) population, including all participants randomized	score on a scale	MEDIAN
SECONDARY	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.	45 days after hospital discharge	intention-to-treat (ITT) population, including all participants randomized	percentage of participants	NUMBER
SECONDARY	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.	90 days after hospital discharge	intention-to-treat (ITT) population, including all participants randomized	percentage of participants	NUMBER
SECONDARY	New, Symptomatic VTE (Inclusive of DVT, PE, or Other Venous Thrombosis) for up to 30 Days After Randomization as Measured by Hospital Records.	30 days after randomization (which occurred at time of hospital discharge)	intention-to-treat (ITT) population, including all participants randomized	percentage of participants	NUMBER
SECONDARY	New, Symptomatic ATE (Inclusive of Ischemic Stroke, MI, or Peripheral Arterial Thromboembolism) for up to 30 Days After Randomization as Measured by Hospital Records.	30 days after randomization (which occurred at time of hospital discharge)	intention-to-treat (ITT) population, including all participants randomized	percentage of participants	NUMBER
OTHER_PRE_SPECIFIED	Percentage of Participants With All-cause Mortality	30 days following discharge from hospital	intention-to-treat (ITT) population, including all participants randomized	percentage of participants	NUMBER
OTHER_PRE_SPECIFIED	The Incidence of All-cause Rehospitalization for up to 90 Days After Randomization	90 days following discharge from hospital
OTHER_PRE_SPECIFIED	The Individual Domains of EQ5D and the EQ5D Visual Analog Scale for 30 and 90 Days After Randomization	30 and 90 days following discharge from hospital

Source ClinicalTrials.gov

Results by group16

Each measurement the trial posted, group by group, in the words and numbers it posted.

Outcome	Group	Value	Spread	Units
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.	Placebo	2.31	95% Confidence Interval 1.27 to 3.84	percentage of participants
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.	Apixaban	2.13	95% Confidence Interval 1.14 to 3.62	percentage of participants
The Composite Outcome of All-cause Mortality and the EuroQoL Group 5-Dimension (EQ5D) Index Score.	Placebo	0.93	Inter-Quartile Range 0.78 to 1.00	score on a scale
The Composite Outcome of All-cause Mortality and the EuroQoL Group 5-Dimension (EQ5D) Index Score.	Apixaban	0.93	Inter-Quartile Range 0.75 to 1.00	score on a scale
The Composite Outcome of All-cause Mortality and the EQ5D Index Score.	Placebo	0.94	Inter-Quartile Range 0.76 to 1.00	score on a scale
The Composite Outcome of All-cause Mortality and the EQ5D Index Score.	Apixaban	0.94	Inter-Quartile Range 0.74 to 1.00	score on a scale
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.	Placebo	2.80	95% Confidence Interval 1.64 to 4.44	percentage of participants
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.	Apixaban	2.46	95% Confidence Interval 1.38 to 4.02	percentage of participants
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.	Placebo	2.80	95% Confidence Interval 1.64 to 4.44	percentage of participants
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.	Apixaban	3.11	95% Confidence Interval 1.89 to 4.82	percentage of participants

1 to 10 of 16Source ClinicalTrials.gov

See all 16 results by group

Participant flow6

How many started, completed or left each group, period by period.

Period	Milestone	Group	Participants
Overall Study	STARTED	Placebo	607
Overall Study	STARTED	Apixaban	610
Overall Study	COMPLETED	Placebo	581
Overall Study	COMPLETED	Apixaban	578
Overall Study	NOT COMPLETED	Placebo	26
Overall Study	NOT COMPLETED	Apixaban	32

Source ClinicalTrials.gov

Adverse events396

Each adverse event the trial posted, group by group: the participants affected out of those at risk.

Type	Event	Organ system	Group	Affected	At risk
other	ABDOMINAL PAIN	Gastrointestinal disorders	Apixaban	1	610
other	ABDOMINAL PAIN	Gastrointestinal disorders	Placebo	0	607
other	ABNORMAL BLEEDING	Vascular disorders	Apixaban	1	610
other	ABNORMAL BLEEDING	Vascular disorders	Placebo	0	607
other	ACUTE BACTERIAL SINUSITIS	Infections and infestations	Apixaban	0	610
other	ACUTE BACTERIAL SINUSITIS	Infections and infestations	Placebo	1	607
other	ACUTE PROSTATITIS	Reproductive system and breast disorders	Apixaban	0	610
other	ACUTE PROSTATITIS	Reproductive system and breast disorders	Placebo	1	607
other	ANEMIA	Blood and lymphatic system disorders	Apixaban	1	610
other	ANEMIA	Blood and lymphatic system disorders	Placebo	0	607

1 to 10 of 396Source ClinicalTrials.gov

See all 396 adverse events

Adverse event totals6

The totals the trial posted for each group.

Total	Group	Affected	At risk
Total, all-cause mortality	Apixaban	12	610
Total, all-cause mortality	Placebo	9	607
Total, other adverse events	Apixaban	80	610
Total, other adverse events	Placebo	90	607
Total, serious adverse events	Apixaban	71	610
Total, serious adverse events	Placebo	66	607

Source ClinicalTrials.gov

Papers2

The papers the trial lists on ClinicalTrials.gov.

PMID	Listed as	Source
36940444	DERIVED	PubMed
37591523	DERIVED	PubMed

Grants0

The grants NIH RePORTER links to the trial, newest funded first: NIH's, and some of AHRQ's, CDC's, FDA's and VA's. Each shows its title, principal investigators, organization and funder in its newest year.

None in this release.

Trial comparisons2

Comparisons of the trial's two groups, calculated by ConductScience from the counts it posted.

Comparison	Source
Apixaban vs Placebo: deaths from any cause	Trial comparisons
Apixaban vs Placebo: serious adverse events	Trial comparisons

Tests0

The ConductCognition tests this trial's registered outcomes name, as ScienceGraph matched them in trial-tests-2026-11-12-0.2.1.

None in this release.

Data dates

The day each source was copied for this release.

ClinicalTrials.gov: 2026-11-12; ClinicalTrials.gov
Results, from AACT: 2026-03-23; AACT
NIH grant links: 2026-11-13; NIH RePORTER

Sources 3

ClinicalTrials.gov's posted results, through CTTI's AACTFreely available. Acknowledgement requested
ClinicalTrials.govNo license stated
NIH RePORTER's clinical studies and project filesPublic domain

Each source's terms

ClinicalTrials.gov's posted results, through CTTI's AACTClinicalTrials.gov data via Aggregate Analysis of ClinicalTrials.gov (AACT), CTTI. CTTI makes its materials freely available and requests acknowledgement. https://aact.ctti-clinicaltrials.org/documentation/299
ClinicalTrials.govnone stated
NIH RePORTER's clinical studies and project filesPublic domain (NIH RePORTER)

ClinicalTrials.gov's data carry an international copyright outside the United States: https://clinicaltrials.gov/about-site/terms-conditions.

For software

Read this trial from software.

The record and each of its lists are JSON, twenty rows a page. No key.

GET https://conductscience.org/api/trials/v1/NCT04650087

GET https://conductscience.org/api/trials/v1/NCT04650087/events?page=2

API reference For AI assistants