Effect of Antithrombotic Therapy on Clinical Outcomes in Outpatients With Clinically Stable Symptomatic COVID-19: The ACTIV-4B Randomized Clinical Trial
- terminated early
- Terminated early by DSMB for lower than anticipated event rates, after enrollment of 9% of planned participants
Authors' conclusion
Among symptomatic clinically stable outpatients with COVID-19, treatment with aspirin or apixaban compared with placebo did not reduce the rate of a composite clinical outcome.
Study context
- Population
- Symptomatic but clinically stable outpatients with COVID-19 (platelets >100,000/mm³, eGFR >30 mL/min/1.73 m²)558 initiated treatment
- Participants
- 657 outpatients
- Comparison
- Aspirin or apixaban vs placebo
- Aspirinn = 164
- 2.5-mg apixabann = 165
- 5-mg apixabann = 164
- Placebon = 164reference
- Primary endpoint
- Composite of:
- All-cause mortality
- Symptomatic venous or arterial thromboembolism
- MI
- Stroke
- Hospitalization for CV or pulmonary cause
Methodological detailsadaptive, double-blind, placebo-controlled, minimal-contact, 52 US sites, 22 (3.3%) hospitalized for COVID-19 before initiating treatment
- Adaptive
- Double-blind
- Placebo-controlled
- Minimal-contact
- 52 US sites
- 22 (3.3%) hospitalized for COVID-19 before initiating treatment
Primary result
As reported in the abstract
Each group vs placeboRisk difference (95% CI)
2.5-mg apixaban
0.7%(−2.1% to 4.1%)
5-mg apixaban
1.4%(−1.5% to 5.0%)
- Aspirin · CI not calculable
- risk difference 0.0%
Safety
| Outcome | Risk difference (95% CI) | |
|---|---|---|
| Bleeding events (none major)Aspirinvs PlaceboParticipants who initiated therapy | 2.0% (−2.7% to 6.8%) | |
| Bleeding events (none major)2.5-mg apixabanvs PlaceboParticipants who initiated therapy | 4.5% (−0.7% to 10.2%) | |
| Bleeding events (none major)5-mg apixabanvs PlaceboParticipants who initiated therapy | 6.9% (1.4%–12.9%) | |
| −1001020Difference (linear scale) |
Original publication
Effect of Antithrombotic Therapy on Clinical Outcomes in Outpatients With Clinically Stable Symptomatic COVID-19: The ACTIV-4B Randomized Clinical Trial. JAMA. Published 2 November 2021. doi:10.
Composed by AI from the published abstract and checked against it. How Briefs are made →