Abelacimab for Prevention of Venous Thromboembolism

This phase 2 trial evaluated the efficacy and safety of abelacimab—a monoclonal antibody that locks factor XI in its inactive form for thromboprophylaxis after total knee arthroplasty. A total of 412 patients were randomized to one of three single-dose intravenous regimens of abelacimab (30 mg, 75 mg, 150 mg) or to daily subcutaneous enoxaparin. The primary efficacy outcome venous thromboembolism detected by mandatory venography or confirmed symptomatic events occurred in 13% (30 mg), 5% (75 mg), and 4% (150 mg) of abelacimab groups versus 22% in the enoxaparin group. The 30 mg dose was noninferior; the 75 mg and 150 mg doses were superior (P<0.001). Bleeding rates were low across all groups, with no major bleeding in any arm. The trial demonstrates that postoperative factor XI inhibition is effective and well tolerated, supporting abelacimab as a promising anticoagulant.

This phase 2 trial evaluated the efficacy and safety of abelacimab—a monoclonal antibody that locks factor XI in its inactive form for thromboprophylaxis after total knee arthroplasty. A total of 412 patients were randomized to one of three single-dose intravenous regimens of abelacimab (30 mg, 75 mg, 150 mg) or to daily subcutaneous enoxaparin. The primary efficacy outcome venous thromboembolism detected by mandatory venography or confirmed symptomatic events occurred in 13% (30 mg), 5% (75 mg), and 4% (150 mg) of abelacimab groups versus 22% in the enoxaparin group. The 30 mg dose was noninferior; the 75 mg and 150 mg doses were superior (P<0.001). Bleeding rates were low across all groups, with no major bleeding in any arm. The trial demonstrates that postoperative factor XI inhibition is effective and well tolerated, supporting abelacimab as a promising anticoagulant.