Intermediate-Dose Versus Standard-Dose Prophylactic Anticoagulation in Patients with COVID-19 Admitted to the Intensive Care Unit: 90-Day Results from the INSPIRATION Randomized Trial

Background: Thrombotic complications are considered among the main extrapulmonary manifestations of coronavirus disease 2019 (COVID-19). The optimal type and duration of prophylactic antithrombotic therapy in these patients remain unknown.

Methods: This article reports the final (90-day) results of the Intermediate versus Standard-dose Prophylactic anticoagulation In cRitically-ill pATIents with COVID-19: An opeN label randomized controlled trial (INSPIRATION) study. Patients with COVID-19 admitted to intensive care were randomized to intermediate-dose versus standard-dose prophylactic anticoagulation for 30 days, irrespective of hospital discharge status. The primary efficacy outcome was a composite of adjudicated venous or arterial thrombosis, treatment with extracorporeal membrane oxygenation (ECMO), or all-cause death. The main safety outcome was major bleeding.

Results: Of 600 randomized patients, 562 entered the modified intention-to-treat analysis (median age [Q1, Q3]: 62 [50, 71] years; 237 [42.2%] women), of whom 336 (59.8%) survived to hospital discharge. The primary outcome occurred in 132 (47.8%) of patients assigned to intermediate dose and 130 (45.4%) patients assigned to standard-dose prophylactic anticoagulation (hazard ratio [HR]: 1.21, 95% confidence interval [CI]: 0.95-1.55,  = 0.11). Findings were similar for other efficacy outcomes, and in the landmark analysis from days 31 to 90 (HR: 1.59, 95% CI: 0.45-5.06). There were 7 (2.5%) major bleeding events in the intermediate-dose group (including 3 fatal events) and 4 (1.4%) major bleeding events in the standard-dose group (none fatal) (HR: 1.82, 95% CI: 0.53-6.24).

Conclusion: Intermediate-dose compared with standard-dose prophylactic anticoagulation did not reduce a composite of death, treatment with ECMO, or venous or arterial thrombosis at 90-day follow-up.